TWI716925B - Pickup system for semiconductor die - Google Patents

Abstract

The subject of the present invention is to properly balance the suppression of damage of the semiconductor die and the increase in the speed of pickup during the pickup of the semiconductor die. The present invention includes: a suction head 18, which adsorbs the semiconductor die 15; a suction mechanism 100, which is connected to the suction head and sucks air from the surface 18a of the suction head; and a flow sensor 106, which detects the suction air flow rate of the suction mechanism; The platform 20 includes an adsorption surface 22 for adsorbing the back surface 12b of the cut sheet 12; an opening pressure switching mechanism 80 switches between a first pressure close to vacuum and a second pressure close to atmospheric pressure when picking up. The opening pressure of the opening 23; and the control unit 150, which acquires the time change of the suction air flow rate detected by the flow sensor when picking up a specific semiconductor die, and obtains the semiconductor die self-cut sheet based on the time change The ease of peeling of the material is based on the ease of peeling, and the number of times of switching during subsequent semiconductor die pickup is changed.

Description

Pickup system for semiconductor die

The present invention relates to a pickup system for semiconductor die used in a bonding device (bonding system).

Semiconductor dies are manufactured by cutting a 6-inch or 8-inch wafer into a predetermined size. When cutting, a dicing sheet is attached to the back surface, and the wafer is cut from the surface side with a dicing saw or the like to prevent the semiconductor die from falling apart after cutting. At this time, the dicing sheet attached to the back surface is slightly cut but not cut, and each semiconductor die is maintained. Then, the cut semiconductor dies are picked up one by one from the dicing sheet and sent to the next step such as die bonding.

As a method of picking up semiconductor dies from a dicing sheet, the following method is proposed: in a state where the dicing sheet is adsorbed on the surface of a disc-shaped adsorption plate, and the semiconductor die is adsorbed on a collet, The semiconductor die is lifted by a block arranged at the center of the suction plate, and the suction head is raised to pick up the semiconductor die from the diced sheet (for example, refer to FIGS. 9 to 22 of Patent Document 1). When peeling the semiconductor die from the dicing sheet, it is effective to peel off the peripheral portion of the semiconductor die first, and then peel off the center portion of the semiconductor die. Therefore, in the prior art described in Patent Document 1, Use the following method, namely: divide the top block into top Three blocks, the block that lifts the surrounding part of the semiconductor crystal grain, the block that lifts the center of the semiconductor crystal grain, and the block that lifts the middle of the semiconductor crystal grain, are first raised to a predetermined height, and then the center and the center The blocks rise higher than the surrounding blocks, and finally the central block rises higher than the middle block.

In addition, the following method has also been proposed: in a state where the dicing sheet is adsorbed to the surface of a disc-shaped ejector cap, and the semiconductor die is adsorbed to the suction head, the suction head and the periphery, middle, After each top block in the center rises to a specified height higher than the surface of the top hat, the height of the suction head is still maintained at that height, and the top block is lowered below the top hat surface in the order of the surrounding top block and the middle top block The dicing sheet is peeled from the semiconductor die (for example, refer to Patent Document 2).

In the case of using the methods described in Patent Document 1 and Patent Document 2 to peel off the dicing sheet from the semiconductor crystal grains, such as FIGS. 40, 42, and 44 of Patent Document 1, and FIGS. 4A to 4D of Patent Document 2 5A to 5D, before the semiconductor die is peeled off, the semiconductor die may be bent and deformed together with the dicing sheet while still attached to the dicing sheet. If the peeling action of the dicing sheet is continued while the semiconductor die is bent and deformed, the semiconductor die may sometimes be damaged. Therefore, the following method is proposed: As described in Figure 31 of Patent Document 1, according to The change in the flow rate of the suction air of the suction head detects the bending of the semiconductor die, and as described in FIG. 43 of Patent Document 1, when the suction flow rate is detected, it is determined that the semiconductor die has been deformed and the top block temporarily After falling, the top block is raised again. Furthermore, Patent Document 3 also discloses detecting (discriminating) the bending (deflection) of the semiconductor die based on the change in the flow rate of the suction air from the suction head.

[Prior Art Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent No. 4945339

[Patent Document 2] Specification of US Patent No. 8092645

[Patent Document 3] Japanese Patent No. 5813432

In recent years, semiconductor crystal grains have become very thin, for example, there are also semiconductor crystal grains of about 20 μm. On the other hand, the thickness of the dicing sheet is about 100 μm, so the thickness of the dicing sheet also reaches 4 to 5 times the thickness of the semiconductor die. If such a thin semiconductor crystal grain is to be peeled off from the dicing sheet, the deformation of the semiconductor crystal grain following the deformation of the dicing sheet is likely to occur more clearly. In the prior art, there is a possibility of damaging the semiconductor die when picking up the semiconductor die from the dicing sheet, and there is room for improvement.

In addition, in the prior art, sufficient research has not been conducted on the speed-up of semiconductor die pickup. In order to suppress the damage of the semiconductor crystal grains, it is necessary to promote the peeling of the semiconductor crystal grains from the dicing sheet, and the time required for the peeling operation (pickup operation) becomes longer. On the other hand, in order to improve productivity, it is also desired to shorten the time required for the peeling operation and to increase the speed of picking.

For example, even if the same type of semiconductor die is picked up continuously, the peelability of the semiconductor die from the diced sheet may change. For example, the semiconductor die picked up at first has good peelability (easy peeling), but the semiconductor chip picked up later There is a possibility that the peelability of the crystal grains is worse than that (easy peeling becomes lower). Or, there is the opposite possibility. In the former case, if the peeling action to further promote the peeling is not changed, the semiconductor crystal grains will be damaged. In the latter case, although the peeling action will not be changed and the semiconductor die will not be damaged, although the semiconductor die can be picked up in a shorter time, it takes a long time to pick up the semiconductor die. When picking up a plurality of semiconductor dies in succession, it is desirable that the suppression of damage to the semiconductor dies and the increase in the speed of picking up the semiconductor dies be appropriately balanced.

The object of the present invention is to reliably suppress damage to semiconductor crystal grains when picking up semiconductor crystal grains, and to appropriately balance the suppression of semiconductor crystal grain damage and the speeding up of semiconductor crystal grain picking when multiple semiconductor crystal grains are continuously picked up .

The semiconductor die picking system of the present invention is a semiconductor die picking system that picks up the semiconductor die attached to the surface of the dicing sheet from the dicing sheet, and is characterized in that it includes: a suction head to absorb the semiconductor die; The suction mechanism is connected with the suction head and sucks air from the surface of the suction head; the flow sensor detects the flow of the suction air sucked by the suction mechanism; the platform includes the suction surface that adsorbs the back of the cut sheet; the opening pressure A switching mechanism that switches the opening pressure of the opening provided on the suction surface of the platform between a first pressure close to vacuum and a second pressure close to atmospheric pressure; and a setting unit that sets switching including the opening pressure when picking up semiconductor dies The number of picking parameters. When the setting unit picks up the semiconductor die, it acquires the time change of the suction air flow rate detected by the flow sensor, that is, the flow rate change, and calculates the peeling of the semiconductor die from the diced sheet based on the flow rate change Evaluation value based on The evaluation value changes the pick-up parameters when picking up other semiconductor dies after picking up the semiconductor die.

In the semiconductor die picking system of the present invention, it is also preferable that the setting unit changes the time for maintaining the opening pressure at the first pressure when picking up the other semiconductor die based on the evaluation value.

In the semiconductor die picking system of the present invention, it is also preferable to further include a plurality of moving elements, the plurality of moving elements are arranged in the opening, and the front end surface is at a first position higher than the suction surface When the semiconductor die is picked up, a plurality of moving elements are sequentially moved from the first position to the second position at predetermined time intervals, or at a predetermined time interval between the second position and the second position lower than the first position. The combination moves from the first position to the second position at the same time, and the setting unit changes the predetermined time when the other semiconductor die is picked up based on the evaluation value.

In the semiconductor die picking system of the present invention, it is also preferable that the setting unit changes the moving from the first position to the second position while picking up the other semiconductor die based on the evaluation value. The number of moving components.

In the semiconductor die picking system of the present invention, it is also preferable to set the opening pressure to be switched between the first pressure and the second pressure when picking up the semiconductor die, so as to perform cutting that is sucked by the opening. The initial peeling of the sheet from the semiconductor die, and the flow rate change is the time change of the suction air flow rate detected by the flow sensor during the initial peeling.

In the semiconductor die picking system of the present invention, it is also preferable that the number of switching is the switching between the first pressure and the second pressure during the initial peeling. The number of opening pressures.

In the semiconductor die picking system of the present invention, it is also preferable that the setting unit changes the semiconductor die from the tip landing on the semiconductor die when the other semiconductor die is peeled from the dicing sheet based on the evaluation value. The waiting time until the lifting of the semiconductor die is started.

In the semiconductor die picking system of the present invention, it is also preferable to include a storage portion that stores an expected flow rate change, and the expected flow rate change is a situation where the semiconductor die is well picked up from the diced sheet Next, the time change of the suction air flow rate when the semiconductor die is picked up, and the setting unit obtains an evaluation value based on the correlation value between the flow rate change when the semiconductor die is picked up and the expected flow rate change.

In the semiconductor die picking system of the present invention, it is also preferable to further include an inspection section that performs crack inspection of the semiconductor die, and performs the semiconductor die picking up a predetermined number of times or more. The switched semiconductor die is the object of crack inspection.

In the semiconductor die picking system of the present invention, it is also preferable that the setting unit acquires the flow rate change of the semiconductor die constituting one or more wafers, and obtains an evaluation value based on each flow rate change, based on A plurality of evaluation values change the picking parameters when picking up the other semiconductor die.

In the semiconductor die picking system of the present invention, it is also preferably configured to include a storage unit that stores a table of parameter values of picking parameters that have a corresponding relationship with a plurality of level values, and a table of the picking parameters currently applied. The level value of the parameter value The previous level value, using the current level value as the index (key), read the parameter value of the picking parameter from the table, and use the parameter value of the picking parameter to pick up the semiconductor die. The setting unit makes the current level value based on the evaluation value Migrating to another level value, thereby changing the parameter value of the picking parameter when picking up the other semiconductor die.

In the semiconductor die picking system of the present invention, it is also preferable that the semiconductor die for which the evaluation value is calculated is a specific semiconductor die, and the setting unit obtains the evaluation value based on one or more specific semiconductor die As the representative crystal grain evaluation value of these representative values, when the representative crystal grain evaluation value is higher than the first predetermined value, when the other semiconductor crystal grain is picked up, it is the same as when the specific semiconductor crystal grain is picked up. Compared with the number of switching times, the number of switching times is reduced. In the case where the evaluation value of the representative die is lower than the second predetermined value, when the other semiconductor die is picked up, the switching is performed when picking up a specific semiconductor die Compared with the number of times, the number of switching times is increased, and the second predetermined value is a value lower than the first predetermined value.

In the semiconductor die picking system of the present invention, it is also preferable that the semiconductor die for which the evaluation value is calculated is a specific semiconductor die, and the setting unit obtains the evaluation value based on one or more specific semiconductor die As the representative crystal grain evaluation value of these representative values, when the representative crystal grain evaluation value is higher than the third predetermined value, when the other semiconductor crystal grains are picked up, the difference between when picking up the specific semiconductor crystal grain is different When the opening pressure is maintained at the first pressure, the time is shortened. When the evaluation value of the representative die is lower than the fourth predetermined value, when picking up the other semiconductor die, it is different from picking up a specific semiconductor die. The time for maintaining the opening pressure at the first pressure during the crystal grain is extended, and the fourth predetermined value is lower than the first pressure. Three-rated value.

In the semiconductor die picking system of the present invention, it is also preferable that the semiconductor die for which the evaluation value is calculated is a specific semiconductor die, and the setting unit obtains the evaluation value based on one or more specific semiconductor die As the representative crystal grain evaluation value of these representative values, when the representative crystal grain evaluation value is higher than the fifth predetermined value, when the other semiconductor crystal grains are picked up, and when the specific semiconductor crystal grain is picked up, Compared with the predetermined time, the predetermined time is shortened. When the evaluation value of the representative die is lower than the sixth predetermined value, when the other semiconductor die is picked up, the predetermined time when picking up the specific semiconductor die Compared with the time, the predetermined time is extended, and the sixth predetermined value is a value lower than the fifth predetermined value.

In the semiconductor die picking system of the present invention, it is also preferable that the semiconductor die for which the evaluation value is calculated is a specific semiconductor die, and the setting unit obtains the evaluation value based on one or more specific semiconductor die As the representative crystal grain evaluation value of these representative values, when the representative crystal grain evaluation value is higher than the seventh prescribed value, when picking up the other semiconductor crystal grains, it is the same as when picking up specific semiconductor crystal grains. Compared with the number of moving elements moving from the first position to the second position, the number of moving elements is increased, In the case where the evaluation value of the representative die is lower than the eighth prescribed value, when picking up the other semiconductor die, it is the same as picking up a specific semiconductor die while moving from the first position to the second position Compared with the number of moving elements, the number of moving elements is reduced, and the eighth prescribed value is lower than the seventh prescribed value.

In the semiconductor die picking system of the present invention, it is also preferably set as: The semiconductor crystal grain for which the evaluation value is obtained is a specific semiconductor crystal grain, and the setting unit obtains the representative crystal grain evaluation value as the representative value based on the evaluation value of one or more specific semiconductor crystal grains. If the value is higher than the ninth predetermined value, when the other semiconductor die is picked up, the standby time is shortened compared to the standby time when the specific semiconductor die is picked up, and the representative die evaluation value When the value is lower than the tenth predetermined value, when the other semiconductor die is picked up, the standby time is extended compared to the standby time when the specific semiconductor die is picked up, and the tenth predetermined value A value lower than the ninth prescribed value.

In the semiconductor die picking system of the present invention, it is also preferable that the semiconductor die for which the evaluation value is calculated is a specific semiconductor die, and the setting unit compares the evaluation value of one or more specific semiconductor die with the first The eleventh specified value is compared, and the number of evaluation values higher than the eleventh specified value is the easy peeling detection number, and the evaluation value of one or more specific semiconductor die is compared with the twelfth specified value. , The number of evaluation values lower than the twelfth predetermined value, that is, the number of difficult-to-peel detections, which is lower than the eleventh predetermined value, is calculated based on the number of easy-to-peel detections and the number of difficult-to-peel detections, Changing the number of times of switching during the pickup of the other semiconductor die after picking up the specific semiconductor die.

In the semiconductor die picking system of the present invention, it is also preferable that the semiconductor die for which the evaluation value is calculated is a specific semiconductor die, and the setting unit compares the evaluation value of one or more specific semiconductor die with the first The eleventh specified value is compared, the number of evaluation values higher than the eleventh specified value, that is, the easy peeling detection number, is calculated, and the evaluation value of one or more specific semiconductor die is compared with the twelfth specified value. The number of evaluation values lower than the twelfth predetermined value, that is, the number of difficult-to-peel detections, is calculated. The twelfth predetermined value is a value lower than the eleventh predetermined value, based on the number of easy-to-peel detections and the number of difficult-to-peel detections , Changing the time during which the opening pressure is maintained at the first pressure when the other semiconductor die is picked up after the specific semiconductor die is picked up.

In the semiconductor die picking system of the present invention, it is also preferable that the semiconductor die for which the evaluation value is calculated is a specific semiconductor die, and the setting unit compares the evaluation value of one or more specific semiconductor die with the first The eleventh specified value is compared, and the number of evaluation values higher than the eleventh specified value is the easy peeling detection number, and the evaluation value of one or more specific semiconductor die is compared with the twelfth specified value. , The number of evaluation values lower than the twelfth predetermined value, that is, the number of difficult-to-peel detections, which is lower than the eleventh predetermined value, is calculated based on the number of easy-to-peel detections and the number of difficult-to-peel detections, The predetermined time during the pickup of the other semiconductor die after the pickup of the specific semiconductor die is changed.

In the semiconductor die picking system of the present invention, it is also preferable that the semiconductor die for which the evaluation value is calculated is a specific semiconductor die, and the setting unit compares the evaluation value of one or more specific semiconductor die with the first The eleventh specified value is compared, and the number of evaluation values higher than the eleventh specified value is the easy peeling detection number, and the evaluation value of one or more specific semiconductor die is compared with the twelfth specified value. , The number of evaluation values lower than the twelfth predetermined value, that is, the number of difficult-to-peel detections, which is lower than the eleventh predetermined value, is calculated based on the number of easy-peel detections and the number of difficult-to-peel detections, The number of the moving elements during the pick-up of the other semiconductor die after picking up the specific semiconductor die is changed.

In the semiconductor die picking system of the present invention, it is also preferable that the semiconductor die for which the evaluation value is calculated is a specific semiconductor die, and the setting unit compares the evaluation value of one or more specific semiconductor die with the first The eleventh specified value is compared, and the number of evaluation values higher than the eleventh specified value is the easy peeling detection number, and the evaluation value of one or more specific semiconductor die is compared with the twelfth specified value. , The number of evaluation values lower than the twelfth predetermined value, that is, the number of difficult-to-peel detections, which is lower than the eleventh predetermined value, is calculated based on the number of easy-to-peel detections and the number of difficult-to-peel detections, The standby time during the pickup of the other semiconductor die after picking up the specific semiconductor die is changed.

The present invention has the following effects: it is possible to reliably suppress the damage of the semiconductor die when picking up the semiconductor die, and when picking up a plurality of semiconductor die continuously, the damage of the semiconductor die can be suppressed and the pickup of the semiconductor die can be accelerated The balance is appropriate.

10: Wafer holder

11: Wafer

12: cut sheet

12a, 18a: surface

12b: back

13: Ring

14: gap/cut into gap

15: Semiconductor die

16: expansion ring

17: Ring pressing part

18: Suction head

19: Suction hole

20: platform

22: Adsorption surface

23: opening

23a: inner surface

24: base body

26: Slot

27: Adsorption hole

28: Inside the upper side

30: moving components

31: Moving element/circular moving element around

33: Outer peripheral surface

38a, 38b, 47: front face

40: Moving element/Middle ring moving element

41: Middle circular moving element

45: Moving element/Columnar moving element

80: Opening pressure switching mechanism

81, 91, 101: Three-way valve

82, 92, 102: drive unit

83~85, 93~95, 103~105: Piping

90: Adsorption pressure switching mechanism

100: suction mechanism

106: Flow sensor

110: Wafer holder horizontal drive part

120: Platform up and down direction drive unit

130: Suction head drive

140: vacuum device

150: Control Department

151: CPU

152: Storage Department

153: Device/Sensor Interface

154: Data Bus

155: Control Program

156: Control Data

157: Expect traffic changes

158, 158a, 158b: actual flow change

159: parameter table

160: Threshold Limit Table

161: current level value

300: Step difference surface forming mechanism

400: Driving part of step surface forming mechanism

500: Picking system for semiconductor die

600: Pickup control unit (control unit)

602: Setting Unit

a, 201~207, 210~218, 220, 221, 223~232, 241~246, 260, 301: arrow

d: gap

F ₁ ~F ₃ : tensile force

H ₀ ~H ₂ , H ₁ -H ₀ , Hc, Hc ₁ : height

HT1, HT4, HT8: Holding time of the first pressure

IT4, IT8: Fall time interval between moving components

P ₁ : first pressure

P ₂ : second pressure

P ₃ : third pressure

P ₄ : Fourth pressure

S100, S102, S104, S1041, S106, S108, S110, S112, S114, S116, S118, S120, S122, S200, S202, S204, S206, S2061, S208, S210, S212, S214, S216, S218, S220, S222, S224, S226, S228, S230, S232, S234, S236, S238, S240: steps

t, t1~t16, ts1, tr_exp, tr_rel, tc_end: time

WT1, WT4, WT8: Tip standby time

τ: Shear stress

(a): Tip height

(b): Position of columnar moving element

(c): The position of the middle circular moving element

(d): Peripheral circular moving element position

(e): Opening pressure

(f): Air leakage from the tip

FIG. 1 is an explanatory diagram showing the system configuration of a semiconductor die pickup system according to an embodiment of the present invention.

2 is a perspective view showing the platform of the semiconductor die picking system according to the embodiment of the present invention.

Fig. 3 is an explanatory diagram showing a wafer attached to a dicing sheet.

Fig. 4 is an explanatory diagram showing a semiconductor die attached to a dicing sheet.

5A and 5B are explanatory diagrams showing the structure of the wafer holder.

6 is an explanatory diagram showing the operation of the semiconductor die picking system according to the embodiment of the present invention at a predetermined level value.

FIG. 7 is an explanatory diagram showing the operation of the semiconductor die pickup system according to the embodiment of the present invention at a predetermined level value.

FIG. 8 is an explanatory diagram showing the operation of the semiconductor die picking system according to the embodiment of the present invention at a predetermined level value.

9 is an explanatory diagram showing the operation of the semiconductor die picking system according to the embodiment of the present invention at a predetermined level value.

10 is an explanatory diagram showing the operation of the semiconductor die picking system according to the embodiment of the present invention at a predetermined level value.

FIG. 11 is an explanatory diagram showing the operation of the semiconductor die pickup system according to the embodiment of the present invention at a predetermined level value.

FIG. 12 is an explanatory diagram showing the operation of the semiconductor die pickup system according to the embodiment of the present invention at a predetermined level value.

FIG. 13 is an explanatory diagram showing the operation of the semiconductor die pickup system according to the embodiment of the present invention at a predetermined level value.

FIG. 14 is an explanatory diagram showing the operation of the semiconductor die picking system according to the embodiment of the present invention at a predetermined level value.

15 is an explanatory diagram showing the operation of the semiconductor die picking system according to the embodiment of the present invention at a predetermined level value.

FIG. 16 is a schematic diagram of a semiconductor die picking system according to an embodiment of the present invention; An explanatory diagram of the operation at a given level.

FIG. 17 is an explanatory diagram showing the operation of the semiconductor die picking system according to the embodiment of the present invention at a predetermined level value.

18 is a diagram showing the height of the tip, the position of the columnar moving element, the position of the intermediate ring-shaped moving element, the position of the peripheral ring-shaped moving element, and the opening pressure when the semiconductor die picking system according to the embodiment of the present invention is operating at a predetermined level value. , And a graph of the time change of the air leakage of the tip.

19 is a diagram showing the height of the tip, the position of the columnar moving element, the position of the intermediate ring-shaped moving element, the position of the peripheral ring-shaped moving element, and the opening when the pickup system of the semiconductor die according to the embodiment of the present invention operates at another level value. Graph of pressure change over time.

FIG. 20 shows the height of the tip, the position of the columnar moving element, the position of the intermediate ring-shaped moving element, the position of the peripheral ring-shaped moving element, and the opening when the pickup system of the semiconductor die according to the embodiment of the present invention is operating at another level value. Graph of pressure change over time.

FIG. 21 is a diagram of an example of the time change of the opening pressure and the expected flow rate change and the actual flow rate change during the predetermined period of initial peeling in the embodiment of the present invention.

Fig. 22 is a flowchart showing the flow of rank transition control according to the embodiment of the present invention.

FIG. 23 is an explanatory diagram of level transition in the embodiment of the present invention.

Fig. 24 is an explanatory diagram of another level transition according to the embodiment of the present invention.

25 is a diagram showing the flow of level transition control according to another embodiment of the present invention flow chart.

Fig. 26 is a flowchart showing a flow of rank transition control according to another embodiment of the present invention.

Fig. 27 is a functional block diagram of a control unit according to an embodiment of the present invention.

<Composition>

Hereinafter, a semiconductor die pickup system according to an embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, the semiconductor die picking system 500 of this embodiment includes: a wafer holder 10, holding a dicing sheet 12, and moving in a horizontal direction, the dicing sheet 12 is attached with a semiconductor on the surface 12a Die 15; platform 20, arranged on the lower surface of the wafer holder 10, and includes a suction surface 22, the suction surface 22 sucking the back surface 12b of the cut sheet 12; a plurality of moving elements 30, arranged on the platform 20 In the opening 23 of the suction surface 22; the step surface forming mechanism 300 forms a step surface relative to the suction surface 22; the step surface forming mechanism driving part 400 drives the step surface forming mechanism 300; the suction head 18, picks up semiconductors Die 15; opening pressure switching mechanism 80, switching the pressure of the opening 23 of the platform 20; adsorption pressure switching mechanism 90, switching the adsorption pressure of the adsorption surface 22 of the platform 20; suction mechanism 100, sucking from the surface 18a of the suction head 18 Air; vacuum device (VAC) 140; wafer holder horizontal driving part 110, driving the wafer holder 10 in the horizontal direction; platform vertical driving part 120, driving the platform 20 in the vertical direction; suction head driving part 130, along The suction head 18 is driven up, down, left, and right; and the control unit 150 controls the semiconductor die picking system 500.

The stepped surface forming mechanism 300 and the stepped surface forming mechanism drive unit 400 are accommodated In the base portion 24 of the platform 20. The step surface forming mechanism 300 is located at the upper part 28 of the platform 20, and the step surface forming mechanism driving part 400 is located at the lower part of the platform 20. The step surface forming mechanism 300 includes a plurality of moving elements 30 that move in the vertical direction. By the stepped surface forming mechanism driving part 400, each front end surface of the plurality of moving elements 30 moves downward as shown by arrow a in FIG. 1. The details of the moving element 30 will be described later.

The opening pressure switching mechanism 80 that switches the pressure of the opening 23 of the platform 20 includes a three-way valve 81 and a drive unit 82 that drives the three-way valve 81 to open and close. The three-way valve 81 has 3 ports. The first port is connected to the base 24 communicating with the opening 23 of the platform 20 by a pipe 83, the second port is connected to the vacuum device 140 by a pipe 84, and the third port is connected于pipe 85 open to the atmosphere. The driving part 82 connects the first port with the second port and blocks the third port to set the pressure of the opening 23 to the first pressure P ₁ close to the vacuum, or connects the first port with the third port to block the first port The two ports set the pressure of the opening 23 to the second pressure P ₂ close to the atmospheric pressure, thereby switching the pressure of the opening 23 between the first pressure P ₁ and the second pressure P ₂ .

The suction pressure switching mechanism 90 that switches the suction pressure of the suction surface 22 of the platform 20 is the same as the opening pressure switching mechanism 80, and includes a three-way valve 91 with three ports and a drive unit for opening and closing the three-way valve 91 92. The first port is connected to the suction hole 27 communicating with the tank 26 of the platform 20 by the pipe 93, the second port is connected to the vacuum device 140 by the pipe 94, and the third port is connected to the pipe 95 open to the atmosphere. The driving part 92 connects the first port with the second port and blocks the third port to set the pressure of the tank 26 or the adsorption surface 22 to a third pressure P ₃ close to the vacuum, or to connect the first port with the third port The second port is blocked, so that the pressure of the tank 26 or the adsorption surface 22 is set to a fourth pressure P ₄ close to the atmospheric pressure, thereby switching the tank 26 or adsorption between the third pressure P ₃ and the fourth pressure P ₄ The pressure of face 22.

The suction mechanism 100 that sucks air from the surface 18a of the suction head 18 is the same as the opening pressure switching mechanism 80, and includes a three-way valve 101 with three ports and a drive unit 102 that drives the three-way valve 101 to open and close. One port is connected to the suction hole 19 communicating with the surface 18a of the suction head 18 by the pipe 103, the second port is connected to the vacuum device 140 by the pipe 104, and the third port is connected to the pipe 105 open to the atmosphere. The driving unit 102 connects the first port with the second port to block the third port, and sucks air from the surface 18a of the suction head 18 to set the pressure on the surface 18a of the suction head 18 to a pressure close to vacuum, or to make the One port communicates with the third port and blocks the second port, thereby setting the pressure of the surface 18a of the suction head 18 to a pressure close to the atmospheric pressure. In the piping 103 connecting the suction hole 19 of the suction head 18 and the three-way valve 101, a flow sensor 106 is installed. The flow sensor 106 sucks from the surface 18a of the suction head 18 to The air flow rate (suction air flow rate) of the vacuum device 140 is detected.

The wafer holder horizontal direction drive unit 110, the platform vertical direction drive unit 120, and the suction head drive unit 130, for example, drive the wafer holder 10 in the horizontal direction or the vertical direction by a motor and a gear (gear) provided inside. , Platform 20, Suction head 18.

The control unit 150 includes a central processing unit (CPU) 151, a storage unit 152, and a device/sensor interface 153 that performs various arithmetic processing or control processing, and the CPU 151, the storage unit 152, and the device/ A computer connected to the sensor interface 153 using a data bus 154. In the storage unit 152, a control program 155 and control data are stored 156. In addition, the details will be described later. The storage unit 152 stores a parameter table 159 (refer to Table 1), which establishes a corresponding relationship between the level value when the semiconductor die 15 is picked up by the suction head 18 and the parameter value of the peeling parameter; Threshold value table 160 (refer to Table 2); current level value 161, which is the level value applied when picking up; expected flow rate change 157, which is picking up when the semiconductor die 15 is peeled from the dicing sheet 12 well Time change of the suction air flow rate detected by the flow sensor 106; actual flow change 158, which is the time change of the suction air flow actually detected by the flow sensor 106 at the time of pickup. FIG. 27 is a functional block diagram of the control unit 150. The control unit 150 functions as a pickup control unit 600 (control unit) and a setting unit 602 by executing the control program 155.

As shown in Figure 1, the opening pressure switching mechanism 80, the suction pressure switching mechanism 90, the three-way valve 81, the three-way valve 91, and the three-way valve 101 of the three-way valve 81, the drive section 92, and the drive section 102 and the step surface forming mechanism driving part 400, the wafer holder horizontal direction driving part 110, the platform vertical direction driving part 120, the suction head driving part 130, and the vacuum device 140 are respectively connected to the equipment/sensor interface 153, according to the control The command of the unit 150 is driven. In addition, the flow sensor 106 is connected to the device/sensor interface 153, and the detection signal is imported to the control unit 150 for processing.

Next, the details of the suction surface 22 and the moving element 30 of the platform 20 will be described. As shown in FIG. 2, the platform 20 is cylindrical, and a flat suction surface 22 is formed on the upper surface. A square opening 23 is provided in the center of the suction surface 22, and a moving element 30 is installed in the opening 23. As shown in FIG. 6, a gap d is provided between the inner surface 23 a of the opening 23 and the outer peripheral surface 33 of the moving element 30. As shown in Figure 2 As shown, a groove 26 is provided around the opening 23 to surround the opening 23. Each tank 26 is provided with suction holes 27, and each suction hole 27 is connected to the suction pressure switching mechanism 90.

As shown in FIG. 2, the moving element 30 includes a columnar moving element 45 arranged in the center; two intermediate ring-shaped moving elements 40 and an intermediate ring-shaped moving element 41 arranged around the columnar moving element 45; and an intermediate ring The surrounding ring-shaped moving element 40 is thus arranged at the outermost periphery of the peripheral ring-shaped moving element 31. Furthermore, the number of intermediate ring-shaped moving elements here is two, but the number of intermediate ring-shaped moving elements can also be one or more than three. In FIG. 6 and the subsequent drawings, in order to simplify the description, the number of the intermediate ring-shaped moving element 40 is one. As shown in FIG. 6, the front end face 47, front end face 38b, and front end face 38a of the columnar moving element 45, the middle annular moving element 40, and the peripheral annular moving element 31 are located at a height H protruding from the suction surface 22 of the platform 20 _{It is} the first position of ₀ , and constitutes the same surface (the level difference surface with respect to the adsorption surface 22). When picking up the semiconductor die 15, the peripheral ring-shaped moving element 31, the middle ring-shaped moving element 40, and the columnar moving element 45 are moved in the order from the first position to the second position lower than the first position at predetermined time intervals. position. Or, it can move from the first position to the second position at the same time with a combination of predetermined moving elements.

<Set Steps for Cutting Sheets>

Here, the step of setting the dicing sheet 12 to which the semiconductor die 15 is attached to the wafer holder 10 will be described.

As shown in FIG. 3, an adhesive dicing sheet 12 is attached to the back surface of the wafer 11, and the dicing sheet 12 is attached to a metal ring 13. Wafer 11 is so Generally, it is handled in a state of being attached to a metal ring 13 via a cut sheet 12. In addition, as shown in FIG. 4, the wafer 11 is cut from the surface side by a dicing saw or the like in the cutting step to become each semiconductor die 15. Between each semiconductor die 15, a cut-in gap 14 formed during cutting is formed. The depth of the cutting gap 14 is from the semiconductor die 15 to a part of the dicing sheet 12, but the dicing sheet 12 is not cut, and each semiconductor die 15 is held by the dicing sheet 12.

In this way, the semiconductor die 15 on which the dicing sheet 12 and the ring 13 are mounted is mounted on the wafer holder 10 as shown in FIGS. 5A and 5B. The wafer holder 10 includes an annular expand ring (expand ring) 16 having a flange portion, and a ring pressing member 17 for fixing the ring 13 to the flange of the expansion ring 16. The ring presser 17 is driven in the direction of advancing and retreating toward the flange of the expansion ring 16 by a ring presser driving portion not shown. The inner diameter of the expansion ring 16 is larger than the diameter of the wafer on which the semiconductor die 15 is arranged. The expansion ring 16 has a predetermined thickness. The flange is located on the outside of the expansion ring 16 and is attached to the dicing sheet so as to protrude outward. The end face side in the direction of 12. In addition, the outer periphery of the expansion ring 16 on the side of the cut sheet 12 is configured to be curved so that when the cut sheet 12 is mounted on the expansion ring 16, the cut sheet 12 can be smoothly drawn. As shown in FIG. 5B, the dicing sheet 12 to which the semiconductor die 15 is attached is in a substantially planar state before being set on the expansion ring 16.

As shown in FIG. 1, when the cut sheet 12 is set on the expansion ring 16, it is drawn along the curved surface of the upper portion of the expansion ring by the amount of step difference between the upper surface of the expansion ring 16 and the flange surface, so it is fixed to The cut sheet 12 on the expansion ring 16 exerts a stretching force from the center of the cut sheet 12 toward the surroundings. In addition, the cut sheet 12 is Since it extends, the gap 14 between the semiconductor dies 15 attached to the dicing sheet 12 is enlarged.

<Pickup Action>

Next, the pickup operation of the semiconductor die 15 will be described. The easy peelability (peelability) of each semiconductor die 15 from the dicing sheet 12 depends on the thickness of the semiconductor die 15, the thickness of the dicing sheet 12, the adhesion of the dicing sheet 12 to each semiconductor die 15, and the semiconductor The environment (temperature, humidity, etc.) where the picking system 500 of the die is placed varies. In addition, when the semiconductor die 15 of the same type is continuously picked up, the peelability of each semiconductor die from the diced sheet may change. Therefore, the semiconductor die pickup system 500 of the present embodiment can change the peeling operation (pickup operation) during pickup for each semiconductor die 15. In the storage unit 152, a parameter table 159 shown in Table 1 is stored. The parameter table 159 specifies parameter values of peeling parameters (pickup parameters) corresponding to a plurality of level values. The parameter table 159 specifies level 1 with the shortest pick-up time to level 8 with the longest pick-up time. The higher the peelability (easy degree of peeling) of the semiconductor die 15 from the dicing sheet 12, the higher the peelability (easy peelability) of the semiconductor die 15 from the dicing sheet 12, the higher the level 1 or the closer to level 1 when picked up, and the use of the peeling parameters specified by the level value The parameter value performs a peeling action (pickup action). In addition, this setting is performed by the control unit 150 functioning as a setting unit. The details of each peeling parameter will be described later. Hereinafter, taking the case of setting (selecting) level 4 of the parameter table 159 as an example, the pickup operation of the semiconductor die will be described.

[Table 1]

The control unit 150 executes the control program 155 shown in FIG. 1 and functions as a pickup control unit to control the pickup operation of the semiconductor die 15. The control unit 150 controls the peeling operation for peeling the semiconductor die 15 from the dicing sheet 12 as a part of the pickup operation. The control unit 150 first moves the wafer holder 10 in the horizontal direction to above the standby position of the platform 20 by the wafer holder horizontal drive unit 110. Then, the control unit 150 temporarily stops the movement of the wafer holder 10 in the horizontal direction after moving the wafer holder 10 to a predetermined position above the standby position of the stage 20. As described above, in the initial state, each of the front end faces 47, front end faces 38b, and 38a of each moving element 45, moving element 40, and moving element 31 is in the first position protruding from the suction surface 22 of the platform 20 by the height H ₀ . Therefore, the control unit 150 raises the platform 20 by the platform vertical drive unit 120 until the front end faces 47, 38b, and 38a of each moving element 45, moving element 40, and moving element 31 are in close contact with the cutting The back surface 12b of the sheet 12 and the area slightly separated from the opening 23 of the suction surface 22 are in close contact with the back surface 12b of the cut sheet 12. In addition, the area slightly separated from the opening 23 of each of the moving element 45, the moving element 40, and the moving element 31 of the front end surface 47, the front end surface 38b, the front end surface 38a, and the suction surface 22 is in close contact with the back surface 12b of the dicing sheet 12 , The control unit 150 stops the ascent of the platform 20. Then, the control unit 150 adjusts the horizontal position again by the wafer holder horizontal drive unit 110 so that the semiconductor die 15 to be picked up comes to the front end surface of the moving element 30 slightly protruding from the suction surface 22 of the platform 20 ( Directly above the step surface).

As shown in FIG. 6, the size of the semiconductor die 15 is smaller than the opening 23 of the platform 20 and larger than the width or depth of the moving element 30. Therefore, when the position adjustment of the platform 20 is completed, the outer peripheral end of the semiconductor die 15 is on the platform. Between the inner surface 23a of the opening 23 of the 20 and the outer peripheral surface 33 of the moving element 30, that is, it is directly above the gap d between the inner surface 23a of the opening 23 and the outer peripheral surface 33 of the moving element 30. In the initial state, the pressure of the groove 26 or the adsorption surface 22 of the platform 20 is atmospheric pressure, and the pressure of the opening 23 also becomes atmospheric pressure. In the initial state, the front end faces 47, front end faces 38b, and 38a of each moving element 45, moving element 40, and moving element 31 are in the first position protruding from the suction surface 22 of the platform 20 by a height H ₀ . each distal end surface 47, the front end surface 38b, the cutting height of the back surface of the sheet front end 38a of the contact 12 at 12b also protrudes from the surface 22 of the suction height H ₀ of the first position. In addition, at the periphery of the opening 23, the back surface 12b of the dicing sheet 12 slightly floats from the suction surface 22, and in a region separated from the opening 23, it is in a state of being in close contact with the suction surface 22. After the adjustment of the position in the horizontal direction is completed, the control unit 150 lowers the suction head 18 onto the semiconductor die 15 by using the suction head driving unit 130 shown in FIG. 1 to make the surface 18a of the suction head 18 land on the semiconductor die 15 on.

(A) to (f) in FIG. 18 represent the height of the suction head 18, the position of the columnar moving element 45, the position of the intermediate ring-shaped moving element 40, and the peripheral ring shape during the peeling action (pickup action) of level 4 The position of the moving element 31, the opening pressure of the opening 23, and the time change of the air leakage amount of the suction head 18 are graphs. (A) in FIG. 18 shows the height of the surface 18a of the suction head 18, and shows the movement of the suction head 18 after a little time from time t=0 (height Hc ₁ ) to time t2 status. At time t1 during which the suction head 18 is moved by the control unit 150, the drive unit 102 of the suction mechanism 100 switches the three-way valve 101 to the direction in which the suction hole 19 of the suction head 18 and the vacuum device 140 communicate (such as (Shown by arrow 301 in FIG. 7). As a result, the suction hole 19 becomes negative pressure, and air flows into the suction hole 19 from the surface 18a of the suction head 18. Therefore, as shown in (f) of FIG. 18, the suction air detected by the flow sensor 106 The flow rate (air leakage amount) gradually increases from time t1 to time t2. At time t2, when the suction tip 18 hits the semiconductor die 15, the semiconductor die 15 is adsorbed and fixed to the surface 18a, and air cannot flow from the surface 18a. Thereby, at time t2, the amount of air leakage detected by the flow sensor 106 is reduced. The height of the surface 18a of the suction head 18 when the suction head 18 hits the semiconductor die 15, as shown in FIG. 6, becomes the front end surface 47, front end surface 38b, and front end of each moving element 45, moving element 40, and moving element 31 The height of the surface 38 a (the height H ₀ from the adsorption surface 22) is the height Hc obtained by adding the thickness of the dicing sheet 12 and the thickness of the semiconductor die 15.

Next, the control unit 150 outputs the switching of the suction pressure (not shown) of the suction surface 22 of the platform 20 from the fourth pressure P ₄ close to the atmospheric pressure at the time t2 shown in (a) to (f) in FIG. 18 It is the command of the third pressure P ₃ close to the vacuum. In accordance with this command, the drive unit 92 of the suction pressure switching mechanism 90 switches the three-way valve 91 to the direction in which the suction hole 27 and the vacuum device 140 communicate. Then, as shown by the arrow 201 in FIG. 7, the arrow 211 in FIG. 10, the arrow 213 in FIG. 11, the arrow 221 in FIG. 13, the arrow 225 in FIG. 14, the arrow 242 in FIG. 16, and the arrow 245 in FIG. The air is sucked out to the vacuum device 140 through the suction hole 27, and the suction pressure becomes the third pressure P ₃ close to the vacuum. Furthermore, the back surface 12b of the cut sheet 12 at the periphery of the opening 23 is vacuum sucked to the surface of the suction surface 22 as shown by the arrow 202 in FIG. 7. The front end faces 47, 38b, and 38a of each moving element 45, moving element 40, and moving element 31 are in the first position protruding from the suction surface 22 of the platform 20 by a height H ₀ , so the cutting sheet 12 is applied Tensile force F ₁ obliquely downward. The stretching force F ₁ can be decomposed into a stretching force F _{2 for} stretching the cut sheet 12 in the lateral direction and a stretching force F _{3 for} stretching the cut sheet 12 in the downward direction. The tensile force F _{2 in} the lateral direction generates a shear stress τ between the semiconductor crystal grain 15 and the surface 12 a of the dicing sheet 12. Due to the shear stress τ, deviation occurs between the outer peripheral portion or peripheral portion of the semiconductor crystal grain 15 and the surface 12 a of the dicing sheet 12. This deviation becomes an opportunity for separation of the dicing sheet 12 and the outer peripheral portion or peripheral portion of the semiconductor die 15.

FIG. 18 (e), the control unit 150 at time t3, the opening pressure close to the atmospheric output from the second pressure P ₂ switching instruction near vacuum pressure P ₁ is the first. In accordance with this instruction, the drive unit 82 of the opening pressure switching mechanism 80 switches the three-way valve 81 to the direction in which the opening 23 and the vacuum device 140 communicate. Then, as indicated by the arrow 206 in FIG. 8, the air in the opening 23 is sucked into the vacuum device 140. As shown in (e) in FIG. 18, at time t4, the opening pressure becomes the first pressure P ₁ close to the vacuum. Thereby, as shown by the arrow 203 in FIG. 8, the cut sheet 12 located directly above the gap d between the inner surface 23 a of the opening 23 and the outer peripheral surface 33 of the moving element 30 is stretched downward. In addition, the peripheral portion of the semiconductor die 15 located directly above the gap d is stretched by the dicing sheet 12 and thus bends and deforms downward as indicated by an arrow 204. Thereby, the peripheral portion of the semiconductor die 15 is separated from the surface 18a of the suction tip 18. When the suction pressure becomes the third pressure P ₃ close to the vacuum, due to the deviation between the outer peripheral portion of the semiconductor die 15 and the surface 12a of the dicing sheet 12, a self-cut sheet is formed on the periphery of the semiconductor die 15 Since the surface 12a of the material 12 is peeled off, the peripheral portion of the semiconductor die 15 starts to peel from the surface 12a of the dicing sheet 12 while bending and deforming as shown by the arrow 204 in FIG. 8.

As shown in FIG. 8, when the peripheral portion of the semiconductor die 15 leaves the surface 18 a of the suction head 18, as shown by the arrow 205 in FIG. 8, air flows into the suction hole 19 of the suction head 18. The inflowing air flow rate (air leakage amount) is detected by the flow rate sensor 106. As a result, as shown in (f) of FIG. 18, the air leakage amount that has turned to decrease at time t2 and continues to decrease starts to increase again at time t3. Specifically, from time t3 to time t4, as the opening pressure drops from the second pressure P ₂ close to atmospheric pressure to the first pressure P ₁ close to vacuum, the semiconductor die 15 and the dicing sheet 12 are pulled downward together. Since it stretches and bends and deforms, the amount of air leakage that flows into the suction hole 19 of the suction head 18 gradually increases from time t3 to time t4.

Then, as shown in (e) of FIG. 18, the control unit 150 maintains the opening 23 of the platform 20 at the first pressure P ₁ close to the vacuum during the period from time t4 to time t5 (time HT4). This time HT4 is the level 4 "maintaining time of the first pressure" specified in the parameter table 159 of Table 1. In the example in Table 1, HT4 is 130ms. During a first pressure P ₁ is held by the arrows 207 shown in FIG. 9, the peripheral portion of the semiconductor die 15 by the elasticity of the semiconductor die 15 vacuum suction holes 19 of the suction head 18 is gradually returned tip 18的面18a. As a result, at time t4 of (f) in FIG. 18, the air leakage volume decreases and continues to decrease. When the semiconductor die 15 is vacuum-adsorbed to the surface 18a of the suction head 18, the air leakage is slightly earlier than time t5. The amount of leakage becomes almost zero. At this time, the peripheral portion of the semiconductor die 15 is peeled off (initial peeling) from the surface 12a of the dicing sheet 12 located directly above the gap d. Then, as shown in 18 (e), the output control section 150 at time t5 to the second near atmospheric pressure P ₂ opening instruction from near vacuum pressure to the first pressure P ₁ is switching. In accordance with this command, the drive unit 82 of the opening pressure switching mechanism 80 switches the three-way valve 81 to connect the piping 85 open to the atmosphere with the opening 23. Accordingly, the arrow 210 as shown in Figure 10, the air inlet opening 23, therefore, the 18 (e) as shown, from the time t5 toward time t6, the pressure from the opening near the first vacuum pressure P ₁ rises To a second pressure P ₂ close to atmospheric pressure.

Time t1 to time t6 in (a) to (f) in FIG. 18 are initial peeling. In the case where the peelability between the semiconductor die 15 and the dicing sheet 12 is poor (the ease of peeling is low), the peripheral portion of the semiconductor die 15 is stretched by the dicing sheet 12 as shown in the arrow 204 in FIG. It takes a lot of time until the peripheral portion of the semiconductor die 15 like the arrow 207 of 9 returns to the surface 18 a of the suction tip 18. For such a semiconductor die 15, the opening of the pressure applied to the first holding time the pressure P ₁ (in FIG. 18 (e) time time time t5 t4 ~) long, or a first pressure P ₁ in the near vacuum The peeling operation (level value) with a large number of switching opening pressures between the second pressure P ₂ close to the atmospheric pressure promotes the peeling of the peripheral portion of the semiconductor die 15 and the dicing sheet 12.

On the other hand, when the peelability between the semiconductor die 15 and the dicing sheet 12 is good (easy to peel off), the peripheral portion of the semiconductor die 15 is stretched by the dicing sheet 12 as shown by the arrow 204 in FIG. Thereafter, the time until the peripheral portion of the semiconductor die 15 returns to the surface 18a of the suction tip 18 as shown by the arrow 207 in FIG. 9 is short. For this type of semiconductor die 15, the application of maintaining the opening pressure at the first pressure P _{1 for} a short time or switching the opening pressure between the first pressure P ₁ close to vacuum and the second pressure P ₂ close to atmospheric pressure is small The peeling action (level value) of the machine speeds up the pick-up. In addition, in the example of level 4 in (a) to (f) in FIG. 18, the number of times of switching the opening pressure during initial peeling is once (switching from the second pressure P ₂ to the first pressure P ₁ , which since the first pressure P ₁ is switched to the second pressure P ₂ are counted as one views the situation). This is the "number of switching times of opening pressure during initial peeling" (FSN4) of level 4 specified in the parameter table 159 of Table 1.

In addition, as described above, depending on the ease of peeling of the semiconductor die 15, the time from when the peripheral portion of the semiconductor die 15 is stretched by the dicing sheet 12 until the peripheral portion of the semiconductor die 15 returns to the surface 18a of the suction tip 18 Since the change occurs, the time change (actual flow rate change) of the air leakage amount detected by the flow sensor 106 also changes. Therefore, as described in detail later, it is possible to determine the peelability (easy degree of peeling) of the semiconductor die 15 from the dicing sheet 12 based on the actual flow rate change.

Continue with the description of the pickup action. In t6 of (a) to (f) in FIG. 18, when the opening pressure rises to the second pressure P ₂ close to the atmospheric pressure, the cut sheet directly above the gap d is stretched downward due to the vacuum As shown by the arrow 212 in FIG. 10, 12 is returned in the upward direction due to the tensile force applied when being fixed to the wafer holder 10. In addition, the cut sheet 12 on the periphery of the opening 23 is slightly floating from the suction surface 22 due to the tensile force.

When FIG. 18 (e), at time t6 becomes close to the atmospheric pressure opening the second pressure P _2, 150 output the following instructions (d), the control unit 18 in the figure, the instruction is the front end surface 31 of the peripheral annular element moves from the first height to a position 38a (22 counting from the suction surface of the height H ₀ of the initial position) lower height H ₁ of the second position. According to this command, the stepped surface forming mechanism driving unit 400 shown in FIG. 1 is driven, and the peripheral ring-shaped moving element 31 is lowered as shown by an arrow 214 in FIG. 11. The annular peripheral surface 31 of the front end of the movable member 38a to move from the first position (initial position) to the lower side of the height H ₁ and lower than the second position 22 of the suction surface (suction surface 22 from a low height (H ₁ - H ₀ ) position).

Next, as shown in (a) to (f) in FIG. 18, the control unit 150 maintains the state from time t6 to time t7. At this time, the pressure of the opening 23 becomes the second pressure P ₂ close to the atmospheric pressure. Therefore, as shown in FIG. 11, the rear surface 12b of the cut sheet 12 located directly above the gap d and the front end surface 38a of the peripheral annular moving element 31 Leave a gap between.

(E), the control unit 150 outputs at time T7 in FIG. 18 from the opening pressure close to the atmospheric pressure P ₂ is switched to a second pressure command P ₁ of a first near-vacuum. In accordance with this instruction, the drive unit 82 of the opening pressure switching mechanism 80 switches the three-way valve 81 so that the opening 23 communicates with the vacuum device 140. Thereby, as shown by the arrow 215 in FIG. 12, the air in the opening 23 is sucked into the vacuum device 140, and at time t8, the opening pressure becomes the first pressure P ₁ close to the vacuum. When the cut sheet 38a by arrow just above the first opening pressure close to the atmospheric pressure from the second pressure drop P ₂ P ₁ of a vacuum to close when the movable member is located outside the annular distal end surface 31 (opposed) in FIG. 12. 12 As shown at 216, it is stretched toward the lower side so that the back surface 12b is in contact with the front end surface 38a. Thereby, as shown by arrow 217 in FIG. 12, a part of semiconductor die 15 located directly above front end surface 38a in semiconductor die 15 is bent and deformed in the downward direction and leaves the surface 18a of suction tip 18, as shown by the arrow in FIG. As shown at 218, air flows into the suction hole 19 of the suction head 18. The air leakage amount flowing into the suction hole 19 is detected by the flow sensor 106. As shown in FIG. 18(f), the air leakage amount increases from time t7 to time t8 when the opening pressure drops. Then, in the vicinity of the opening pressure reaches a first time point t8 when _a pressure P, the surface facing the tip of arrow 224 as shown in FIG. 13 18a 18 returns the semiconductor die regions 38a and opposing the front end surface 15 of FIG. As a result, around the time t8 in (f) in FIG. 18, the air leakage amount is reduced. When the semiconductor die 15 is vacuum sucked to the surface 18a of the suction head 18 as shown in FIG. 13, the air leakage amount is approximately Becomes zero. At this time, the region facing the front end surface 38a of the semiconductor die 15 is peeled from the surface 12a of the dicing sheet 12. Furthermore, after the area of the semiconductor die 15 facing the front end surface 38a of the semiconductor die 15 is stretched by the dicing sheet 12 as indicated by the arrow 217 of FIG. 12, the time until it returns to the surface 18a of the suction head 18 as indicated by the arrow 224 of FIG. It changes according to the peelability of the semiconductor die 15 and the dicing sheet 12.

Next, as shown in 18 (e), the control unit 150 t9, the output of the opening pressure close to the arrival time from a first vacuum pressure P ₁ is raised to near atmospheric second pressure P ₂ of the instruction. In response to this command, the drive unit 82 of the opening pressure switching mechanism 80 switches the three-way valve 81 so that the opening 23 communicates with the pipe 85 open to the atmosphere. Thereby, as indicated by the arrow 220 in FIG. 13, air flows into the opening 23, and at time t10, the pressure of the opening 23 rises to the second pressure P ₂ close to the atmospheric pressure. Thereby, as shown by the arrow 223 in FIG. 13, the cut sheet 12 directly above the gap d is separated from the front end surface 38a of the peripheral ring-shaped moving element 31 and displaced upward.

At time t10 from (a) to (f) in FIG. 18, the control unit 150 outputs the following command to move the front end surface 38b of the intermediate ring-shaped moving element 40 to the first position (calculated from the suction surface 22) Height H ₀ ) is lower than the second position of height H ₁ , and the front end surface 38a of the peripheral ring-shaped moving element 31 at the second position is moved to a height H lower than the first position (initial position) The third position of ₂ (the position lowered by H ₂ -H ₀ from the adsorption surface 22). According to this command, the stepped surface forming mechanism driving unit 400 shown in FIG. 1 is driven, the middle ring-shaped moving element 40 is lowered as shown by the arrow 227 in FIG. 14, and the peripheral ring-shaped moving element 31 is moved as shown by the arrow 226 decline. The front end surface 38b of the intermediate ring-shaped moving element 40 moves to a second position lowered by a height H ₁ from the first position (a position higher than the suction surface by height H ₀ ) (a position lower by H ₁ -H ₀ from the suction surface 22 ₎ . Position), and the front end surface 38a of the peripheral ring-shaped moving element 31 moves to a third position (a position lowered by H ₂ -H ₀ from the suction surface 22) by the height H ₂ from the first position (initial position). Thereby, as shown in FIG. 14, the front end surface 38 a, the front end surface 38 b, and the front end surface 47 are level difference surfaces having a level difference with each other, and at the same time are level difference surfaces with respect to the suction surface 22.

Next, as shown in (a) to (f) in FIG. 18, the control unit 150 maintains the state from time t10 to time t11. Then, the control unit 150 in FIG. 18 (e) is output at time t11 since the opening pressure close to the atmospheric pressure P ₂ is switched to a second proximity to the first vacuum pressure P ₁ is designated. In accordance with this instruction, the drive unit 82 of the opening pressure switching mechanism 80 switches the three-way valve 81 so that the opening 23 communicates with the vacuum device 140. Thereby, as shown by the arrow 228 in FIG. 15, the air in the opening 23 is sucked into the vacuum device 140, and at time t12, the opening pressure becomes the first pressure P ₁ close to the vacuum. Then, as shown by arrows 229 and 230 shown in FIG. 15, the cut sheet 12 faces the front end surface 38a of the peripheral ring-shaped moving element 31 lowered to the third position, and the middle ring-shaped moving element 40 lowered to the second position The front end surface 38b is stretched and shifted downward. Along with this, the area facing the front end surface 38a and the front end surface 38b of the semiconductor die 15 is also separated from the surface 18a of the suction head 18 as shown by arrow 231 in FIG. Then, as indicated by the arrow 232 in FIG. 15, air flows into the suction hole 19 from between the surface 18 a of the suction head 18 and the semiconductor die 15. The air leakage amount flowing into the suction hole 19 is detected by the flow sensor 106. As shown in FIG. 18(f), the air leakage amount gradually increases from time t11 to time t12 when the opening pressure gradually decreases. Then, the pressure reaches the vicinity of the opening timing t12, _a first pressure P, the arrow 244 as shown in FIG 16 toward the tip surface 18 of the front end surface 18a returns 38a, semiconductor die regions 38b facing the front end face 15 as shown in FIG. As a result, around the time t12 in (f) of FIG. 18, the air leakage amount is reduced. When the semiconductor die 15 is vacuum sucked to the surface 18a of the suction head 18 as shown in FIG. 16, the air leakage amount is approximately zero. In addition, the time to return to the surface 18 a of the suction head 18 varies depending on the peelability of the semiconductor die 15 and the dicing sheet 12.

Next, in 18 (e) As shown, the control unit 150 at time t13 the output from the proximity of the opening pressure of the first vacuum pressure P ₁ is switching instruction to the second pressure P ₂ is close to atmospheric pressure. In response to this command, the drive unit 82 of the opening pressure switching mechanism 80 switches the three-way valve 81 so that the opening 23 communicates with the pipe 85 open to the atmosphere. Then, as indicated by the arrow 241 in FIG. 16, air flows into the opening 23 and the opening pressure rises, so the cut sheet 12 is displaced upward as indicated by the arrow 243 shown in FIG. 16. As shown in (e) in FIG. 18, at time t14, the opening pressure becomes the second pressure P ₂ close to the atmospheric pressure. In this state, as shown in FIG. 16, although the semiconductor die 15 in the region corresponding to the front end surface 47 of the columnar moving element 45 is attached to the dicing sheet 12, most of the semiconductor die 15 is self-cutting. The state where the sheet 12 is peeled off.

Next, at time t14 from (a) to (f) in FIG. 18, the control unit 150 outputs the following command to move the front end surface 47 of the columnar moving element 45 to the first position (from the suction surface The height calculated from 22 is the position of H ₀ ) is lower than the second position of height H ₁ , and the front end surface 38b of the intermediate ring-shaped moving element 40 at the second position is moved to be lower from the first position (initial position) The third position of the height H ₂ (the position lowered by H ₂ -H ₀ from the suction surface 22). According to this instruction, the stepped surface forming mechanism driving unit 400 shown in FIG. 1 is driven, the columnar moving element 45 is lowered as shown by arrow 260 in FIG. 17, and the intermediate annular moving element 40 is lowered as shown by arrow 246 . The front end surface 47 of the columnar moving element 45 moves to a second position lowered by the height H ₁ from the first position (a position higher than the suction surface by height H ₀ ), and the front end surface 38 b of the middle annular moving element 40 moves to The third position lowered by the height H ₂ from the first position (initial position). Thereby, as shown in FIG. 17, the semiconductor die 15 is in a state peeled from the dicing sheet 12.

The control unit 150 outputs a command to raise the suction head 18 at time t15 from (a) to (f) in FIG. 18. According to this instruction, the suction head driving unit 130 shown in FIG. 1 drives the motor to raise the suction head 18 as shown in FIG. 17. When the suction head 18 rises, the semiconductor die 15 is picked up in a state of being sucked by the suction head 18.

After picking up the semiconductor die 15, the control unit 150 returns the front end faces 38a, 38b, and 47 of the moving element 31, the moving element 40, and the moving element 45 to the first position at time t16. the third pressure switching mechanism 90 adsorption pressure surface 22 of the platform 20 from the near-vacuum P ₃ is switched to the fourth near atmospheric pressure P _4. At this point, the pickup is over.

The time t6 to time t16 in (a) to (f) in FIG. 18 described above is the actual separation. In the official release, the moving member 30 from the outside of the front end surface 30 sequentially from the first position to the second position to the inside of the movable element, the pressure P ₁ is the first and the second pressure P ₂ switches between opening pressure, whereby The region of the semiconductor die 15 inside the peripheral portion is peeled from the surface 12 a of the dicing sheet 12. Further, in the official release described above, under a first pressure P ₁ is between the opening of the pressure switch _2, but also in the opening pressure is maintained at a first pressure close to a vacuum state and a second pressure P, the so Each moving element 30 moves sequentially.

Here, the peeling parameters of the peeling operation in (a) to (f) in FIG. 18 described above are confirmed. The peeling operation of (a) to (f) in FIG. 18 described above is performed by applying the parameter value of each peeling parameter specified in the level 4 of the parameter table 159 of Table 1. Specifically, the parameter values of the following peeling parameters were applied. "The number of switching times of the opening pressure during the initial peeling (when switching from the second pressure P ₂ to the first pressure P ₁ and thereafter switching from the first pressure P ₁ to the second pressure P _{2 is} counted as 1 time, the following is the same) "Set FSN4=1 time. The "number of switching times of the opening pressure at the time of main peeling" is set to SSN4=2 times. The opening pressure is maintained at a first pressure P _1, that time, "the first pressure hold time" is set HT4 = 130ms. "The number of moving parts falling at the same time" is set to DN4=0. The "falling time interval between moving elements" when the front end surface of each moving element 30 is sequentially lowered from the first position to the second position is set to IT4=240ms. In addition, the time from when the tip 18 hits the semiconductor die 15 to when the semiconductor die 15 starts to be lifted, that is, the "tip standby time" is set to WT4=710 ms. Moreover, the "pickup time" is PT4=820ms.

<Parameter table>

Here, the parameter table 159 of Table 1 will be described in more detail. According to the peelability of the semiconductor die 15 from the dicing sheet 12, a grade value can be selected (set) from grade 1 to grade 8 in the parameter table 159, and the parameter value of each peeling parameter specified by the grade value can be used. Stripping action. The harder the peeling is, the higher the grade value (low speed grade) is selected.

The parameter value of each peeling parameter of the parameter table 159 has the following tendency corresponding to the change of the grade value. As shown in Table 1, from level 1 to level 8, the "number of switching times of opening pressure during initial peeling" has increased. However, this does not mean that the number of switching will increase whenever the level value changes. There are multiple adjacent level values that switch between The same number of times. The same is true for other stripping parameters. The above situation does not mean that the parameter value will change whenever the level value changes. There are cases where the parameter value is the same in multiple adjacent level values. From level 1 to level 8, the number of "switching times of opening pressure during formal peeling" has increased. In addition, from level 1 to level 8, the "maintaining time of the first pressure" has been extended. From level 1 to level 8, the "fall time interval between moving parts" has been extended. In addition, from level 1 to level 8, the "tip standby time" has been extended. Whenever the level value changes, the "pickup time" will change, and it will become longer from level 1 to level 8. Furthermore, the "pick-up time" is similar to the "tip standby time", but it is not only the suction head standby time, but also includes the time until the suction head 18 is lowered from a predetermined position and landed on the semiconductor die 15, and since the start of the semiconductor die The time from the lifting of the pellet 15 to the rising to a predetermined position. Furthermore, the peeling parameters can also be referred to as "pickup parameters". The so-called "set picking parameter" can be defined as the parameter value of setting the picking parameter (stripping parameter), and the so-called "change picking parameter" can be defined as the parameter value of changing the picking parameter (stripping parameter). In addition, the parameter table 159 of Table 1 may also be referred to as a "condition table", and the parameter value of the peeling parameter may also be referred to as a "pickup condition". Furthermore, the specific parameter values shown in Table 1 are only an example, and of course other values may be used.

Here, as an example of peeling operations other than the above-mentioned level 4 peeling operation, level 1 and level 8 peeling operations will be described. First, the level 8 peeling operation will be described. Level 8 is a level value that should be set in the semiconductor die 15 which is very difficult to peel off. (A) ~ (e) in FIG. 19 shows the height of the suction head 18, the position of the columnar moving element 45, the position of the intermediate circular moving element 40, and the peripheral circular moving element 31 during the peeling action of level 8. Position and opening of opening 23 Diagram of mouth pressure. Comparing the peeling operation of level 8 in (a) to (e) in FIG. 19 and the peeling operation of level 4 in (a) to (f) in FIG. 18, the following can be seen.

In the level 8 peeling operation of (a) to (e) in FIG. 19, the "number of switching times of the opening pressure during initial peeling" is increased to 4 (FSN8). Thereby, even when it is difficult to peel off the periphery of the semiconductor die 15 from the dicing sheet 12, the periphery of the semiconductor die 15 can be sufficiently peeled from the dicing sheet 12. By switching the opening pressure multiple times, it is an image that the dicing sheet 12 attached to the periphery of the semiconductor die 15 is shaken off. Although it takes time, it can be peeled off reliably. In addition, in (a) to (e) in Figure 19, the "retention time of the first pressure" (HT8) at the initial peeling time is set to 150ms (refer to Table 1, the same below, for detailed parameter values, refer to The figure) has been extended. Thereby, the surroundings of the semiconductor die 15 can be promoted to naturally peel off from the dicing sheet 12. Furthermore, in the example of Table 1, regarding the "maintenance time of the first pressure", there is no big difference between level 4 and level 8, but it may be considered to make the difference larger.

In addition, in the level 8 peeling operation of (a) to (e) in FIG. 19, the "number of times of switching the opening pressure at the time of actual peeling" was increased to 4 times (SSN8). Thereby, even in the case where it is difficult to peel off the dicing sheet 12 of the semiconductor die 15 in the inner region than the periphery, the dicing sheet 12 attached to the semiconductor die 15 can be reliably peeled off by shaking off. In addition, in (a) to (e) of FIG. 19, the "maintaining time of the first pressure" (HT8) at the time of actual peeling was extended by 150 ms. Thereby, it is possible to promote the area of the semiconductor die 15 on the inner side of the periphery to naturally peel off from the dicing sheet 12. Furthermore, in the parameter table 159 shown in Table 1, the "first pressure retention time" (HT8) is the same during the initial peeling and the actual peeling. However, the parameter table 159 may also specify that the initial peeling is Different "Maintenance Time of the First Pressure" during the formal peeling. Further, FIG. ~ (E), when peeling or official release times at an initial opening of the pressure switch in the (a) 19 held at the time and therefore there is a plurality of the first pressure P ₁ time, also in the parameter In Table 159, a plurality of "holding times of the first pressure" are respectively specified, and the parameter values of these are different from each other. For example, a plurality of "holding times of the first pressure" are arranged in the order of application in the peeling operation and specified in the parameter table 159.

In addition, in the level 8 peeling operation of (a) to (e) in FIG. 19, the "fall time interval between moving elements" (IT8) was extended to 450 ms. If the time from when the front end surface 38a of the peripheral ring-shaped moving element 31 is lowered from the first position to the second position and the front end surface 38b of the middle ring-shaped moving element 40 is lowered from the first position to the second position is extended, then The region of the semiconductor die 15 facing the front end surface 38a of the peripheral ring-shaped moving element 31 can be promoted to naturally peel off from the dicing sheet 12. Similarly, if the time from when the front end surface 38b of the intermediate ring-shaped moving element 40 is lowered from the first position to the second position to when the front end surface 47 of the columnar moving element 45 is lowered from the first position to the second position is extended , It can promote the region of the semiconductor die 15 facing the front end surface 38b of the intermediate annular moving element 40 to naturally peel off from the dicing sheet 12. Furthermore, the falling time interval between the peripheral ring-shaped moving element 31 and the middle ring-shaped moving element 40 may be different from the falling time interval between the middle ring-shaped moving element 40 and the columnar moving element 45, in this case Next, each fall time interval is specified in the parameter table 159. Furthermore, as shown in Figure 2, the intermediate circular moving element The number of the piece 40 and the intermediate annular moving element 41 may be two or more. In this case, in the peeling operation, set from the intermediate annular moving element 40 on the outer peripheral side to the intermediate annular moving element 40 on the inner peripheral side. 41 descended sequentially. In such a case where the number of the intermediate ring-shaped moving element 40 and the intermediate ring-shaped moving element 41 is two or more, the parameter table 159 can also specify the intermediate ring-shaped moving element 40 and the other intermediate ring-shaped moving element 41. The fall time interval between. Furthermore, for example, it is also possible to specify in the parameter table 159 from the time point of the start of the pick-up operation (time t1 from (a) to (e) in FIG. 19) until the peripheral ring-shaped moving element 31 (the movement that descends first) Element 30) The time from when the first position drops to the second position.

In addition, in the level 8 peeling operation of (a) to (e) in FIG. 19, the "tip standby time" (WT8) was set to 1590 ms and extended. Moreover, in (a) to (e) in FIG. 19, the "pickup time" (PT8) becomes 1700 ms and becomes longer.

Next, the level 1 peeling operation will be described. Level 1 is a level value that should be set in the semiconductor die 15 that is very easy to peel off. (A) to (e) in FIG. 20 show the height of the suction head 18, the position of the columnar moving element 45, the position of the intermediate circular moving element 40, and the peripheral circular moving element 31 during the peeling operation of level 1. The position and the opening pressure of the opening 23 are shown. Comparing the peeling operation of level 1 in (a) to (e) in FIG. 20 and the peeling operation of level 4 in (a) to (f) in FIG. 18, the following can be seen.

In the level 1 peeling operation of (a) to (e) in FIG. 20, the "maintaining time of the first pressure" (HT1) during the initial peeling is set to 100 ms. 了shortened. In the case where the semiconductor die 15 is easily peeled off from the dicing sheet 12, even if the “first pressure retention time” is shortened, the periphery of the semiconductor die 15 is sufficiently peeled off from the dicing sheet 12. By shortening the "maintaining time of the first pressure" in this way, the time required for the peeling action can be shortened.

In addition, in the level 1 peeling operation of (a) to (e) in FIG. 20, the "number of times of switching the opening pressure during the actual peeling" is reduced to one (SSN1). In the case where the semiconductor die 15 is easily peeled from the dicing sheet 12, even if the "number of times of switching the opening pressure at the time of actual peeling" is one, the area of the semiconductor die 15 on the inner side of the periphery is fully self-sufficient from the dicing sheet 12 Peel off. In addition, in (a) to (e) in FIG. 20, the front end faces 38a of the three moving elements 30 (peripheral annular moving element 31, middle annular moving element 40, and columnar moving element 45) are set at time ts1. , The front end surface 38b and the front end surface 47 are simultaneously lowered from the first position to below the second position, and the "number of moving elements lowered simultaneously" is increased to 3 (DN1). In the case where the semiconductor die 15 is easily peeled from the dicing sheet 12, even if the plurality of moving elements 30 are lowered at the same time, the area of the semiconductor die 15 on the inner side of the periphery is immediately peeled from the dicing sheet 12. Furthermore, when the peripheral ring-shaped moving element 31 and the middle ring-shaped moving element 40 are lowered at the same time, and the columnar moving element 45 is lowered after a predetermined time, the "number of moving elements lowered at the same time" becomes 2 One. In addition, in the parameter table 159 of Table 1, two peeling parameters of "the number of moving elements that descend simultaneously" and "the falling time interval between moving elements" are specified, but instead of these, the "peripheral" The falling time interval between the ring-shaped moving element 31 and the intermediate ring-shaped moving element 40", "the falling time interval between the intermediate ring-shaped moving element 40 and the columnar moving element 45" "Interval", "the falling time interval between the intermediate ring-shaped moving element 40 and the other intermediate ring-shaped moving element 41". In this case, in order to lower the plurality of moving elements 30 at the same time, one or two or more of the falling time intervals may be set to zero.

In addition, in the level 1 peeling operation of (a) to (e) in FIG. 20, the "tip standby time" (WT1) was shortened by 460 ms. In addition, in (a) to (e) in FIG. 20, the "pickup time" (PT1) is 570 ms, which is shorter.

As described above, the parameter value of each peeling parameter is changed according to the level value, that is, the peeling operation (pickup operation) is different. By setting a gradation value close to gradation 8 in the semiconductor die 15 that is difficult to peel, and performing the peeling operation, it is possible to suppress damage or picking errors of the semiconductor die 15 during pickup. On the other hand, by setting a gradation value close to gradation 1 in the semiconductor die 15 that is easy to peel, and performing the peeling operation, picking up can be performed in a short time. Furthermore, the multiple level values can be regarded as values indicating the length of time required for picking.

<How to detect peelability>

Next, a method of detecting the peelability of the semiconductor die 15 from the dicing sheet 12 will be described. The peelability of the semiconductor die 15 from the dicing sheet 12 can be detected based on the time change (the actual flow rate change) of the suction air flow rate of the suction head 18 detected by the flow sensor 106.

21 is a diagram showing the time change of the opening pressure during the initial peeling and the air leakage amount (suction air flow rate) of the suction head 18 detected by the flow sensor 106. The meaning of each time of t1, t2, t3, and t4 Compared with those shown in (a) ~ (f) in Figure 18 The meaning of each moment is the same. The solid line 157 in the graph of the air leakage amount in FIG. 21 is the time change of the air leakage amount in the case where the peeling of the semiconductor die 15 from the dicing sheet 12 is good (when the ease of peeling is very high), that is, the expected flow rate change. 157. The expected flow rate change 157 is stored in the storage unit 152 in advance. Specifically, the expected flow rate change 157 stored in the storage unit 152 may be a collection of a plurality of suction air flow rates acquired at a predetermined sampling period, and may be a suction air corresponding to a plurality of discrete time points t. flow. The single-dot chain line 158a and the double-dot chain line 158b in the graph of the air leakage amount of FIG. 21 are the time change of the air leakage amount detected when the semiconductor die 15 is actually picked up from the diced sheet 12, that is, the actual flow rate change 158 example. The actual flow rate change 158 is stored in the storage unit 152 every time a specific semiconductor die 15 is picked up. Specifically, the actual flow rate change 158 stored in the storage unit 152 may be in a form that can be compared with the expected flow rate change 157. For example, like the expected flow rate change 157, it may be a plurality of puffs acquired at a predetermined sampling period. A collection of air flow rates and a suction air flow rate that has a corresponding relationship with a plurality of discrete times t. Furthermore, the actual flow rate change can be referred to as "flow rate change" for short. In addition, the actual flow change may be referred to as "actual flow information", and the expected flow change may be referred to as "expected flow information".

In the semiconductor die 15 from the dicing sheet 12 is peeled off well, when close to a first vacuum pressure P ₁ is started at time t3 opening of the pressure change, the semiconductor die 15 around the surface of the suction head 18 from leaving 18a (Refer to FIG. 8), but the periphery of the semiconductor die 15 immediately returns to the surface 18a of the suction tip 18 (refer to FIG. 9). Therefore, like the expected flow rate change 157 in FIG. 21, the air leakage amount starts to increase from time t3, but immediately turns to decrease (turns to decrease at time tr_exp). In the expected flow rate change 157, the amount of increased air leakage is also small.

On the other hand, in the semiconductor die 15 from the lower case of cutting poor release sheet 12 (easiness of peeling is low), the close when the first vacuum pressure P ₁ is started at time t3 opening of the pressure change, the semiconductor The periphery of the die 15 separates from the surface 18a of the suction tip 18, and after a certain amount of time has passed, the periphery of the semiconductor die 15 returns to the surface 18a of the suction tip 18. Therefore, like the actual flow rate change 158a in FIG. 21, the air leakage amount starts to increase from time t3, and after continuing to increase, it turns to decrease at a time tr_rel later than the time tr_exp. In addition, in the actual flow rate change 158a, the increased air leakage amount is large.

In addition, in the case where the peelability of the semiconductor die 15 from the dicing sheet 12 is very poor (in the case where the ease of peeling is very low), even after the semiconductor die 15 is separated from the surface 18a of the suction head 18 after a certain distance For a certain amount of time, the surroundings of the semiconductor die 15 will not return to the surface 18a of the suction tip 18. Thus, the actual flow 158b changes as shown in FIG. 21, t4 a predetermined time has elapsed since the time tc_end, even if the amount of air leakage from the opening at the time the pressure reaches a first pressure P ₁ of near vacuum also maintaining a large state.

In this way, the worse the peelability of the semiconductor die 15 from the dicing sheet 12 is, the more the actual flow rate change 158 deviates from the expected flow rate change 157. Therefore, comparing the actual flow rate change 158 with the expected flow rate change 157, the more the actual flow rate change 158 is similar to the expected flow rate change 157, the better the peelability (the higher the ease of peeling). Or, the stronger the correlation between the actual flow rate change 158 and the expected flow rate change 157, it is judged as The better the peelability (the higher the ease of peeling). In the present embodiment, the actual flow rate change 158 is compared with the expected flow rate change 157, and these correlation values are obtained. The correlation value is a value of 0 to 1.0, and is set to 1.0 when the actual flow rate change 158 and the expected flow rate change 157 completely match, and the closer the value from 0 is to 1.0, it is determined that the ease of peeling is higher. Furthermore, in the present embodiment, the range of the correlation value is set to 0 to 1.0, but of course it may be other values.

Regarding the period during which the actual flow rate change 158 and the expected flow rate change 157 are compared, for example, the time t1 in FIG. 21 (the time when air is sucked from the surface 18a of the suction head 18) to time tc_end ( since first opening pressure reaches a predetermined time has elapsed time point t4 to time point a first pressure P _1). Alternatively, the comparison may also be performed during the time t3, as part of the initial release period (toward the first pressure opening of the pressure P starts _a time varying) period of ~ tc_end. In addition, the comparison period may be another period, but it is preferably a period that does not change even if the level value peeling operation is changed. In this way, only one pattern of the expected flow rate change 157 can be stored in the storage unit 152, and there is no need to store the pattern of the expected flow rate change 157 for each level value in the storage unit 152.

Furthermore, as the peelability of the semiconductor die 15 from the dicing sheet 12, a value other than the correlation value between the actual flow rate change 158 and the expected flow rate change 157 can also be obtained. For example, the smaller the difference between the value of the expected flow rate change 157 at the time tc_end in FIG. 21 and the value of the actual flow rate change 158 at that time, the better the peelability (the higher the ease of peeling). In addition, for example, the time tr_exp as the time point at which the air leakage flow rate in the expected flow rate change 157 turns from an increase to a decrease is compared with the actual The smaller the difference between the time tr_rel at the point in time when the air leakage flow rate turns from increase to decrease in the international flow rate change 158, it can also be determined that the ease of peeling is higher. In addition, for example, the difference between the maximum value of the air leakage flow rate of the expected flow rate change 157 detected after time t3 in FIG. 21 and the maximum value of the air leakage flow rate of the actual flow rate change 158 detected after that time is smaller, then It can also be judged that the easiness of peeling is higher.

In addition, it is also considered to detect the peelability of the semiconductor die 15 from the dicing sheet 12 without using the expected flow rate change 157. For example, the smaller the value of the actual flow rate change 158 at the time tc_end in FIG. 21, the better the peelability (the higher the ease of peeling). In addition, the correlation value obtained based on the actual flow rate change 158, or an index value indicating the peelability of the semiconductor die 15 from the dicing sheet 12 instead of the correlation value may also be referred to as an "evaluation value".

<Level migration based on peelability>

Next, the transition of the level value (level value of the parameter table 159) applied at the time of picking will be described. As explained later, the semiconductor die picking system 500 obtains the actual flow rate change 158 when picking up one or more specific semiconductor die 15 and calculates it based on each of the obtained one or more actual flow rate changes 158 The correlation value of each specific semiconductor die 15 is obtained, and based on one or more correlation values, the level value applied when the other semiconductor die 15 is picked up after the specific semiconductor die 15 is picked up is changed.

For example, even if the semiconductor die 15 of the same type is continuously picked up from the dicing sheet 12 of the same type, the peelability of the semiconductor die 15 from the dicing sheet 12 may change. The level applied during picking is adjusted by the change of peelability The value shifts, and even if the peelability deteriorates (the ease of peeling becomes lower), it can be picked up stably without damaging the semiconductor die 15; on the other hand, the peelability becomes good (the ease of peeling becomes higher) In the case of, it can be picked up in a shorter time.

In addition, for example, the type of the semiconductor die 15 or the type of the dicing sheet 12 is changed, and it is most suitable for a case where the level value of the pickup is unknown. In this case, first, use the level 8 (refer to Table 1) of the parameter table 159 that can be picked up most stably to pick up, and based on the correlation value of the specific semiconductor die 15, make the level value gradually go to level 1 (Highest speed) migration. In this way, the most suitable level value can be searched out, and the most suitable picking with a balance of stability and high speed can be realized.

Next, the specific level value transition control will be described. FIG. 22 is a flowchart showing the flow of level transition control in this embodiment. In this embodiment, all the semiconductor dies 15 are treated as specific semiconductor dies 15, and every time one or more wafers of semiconductor dies 15 are picked up, there is an opportunity to shift the level value. Regarding the migration of the level value, there are migration from the level value applied by the current picking (current level value) to the next level value (see FIG. 23), and migration without limiting the migration target level value (see FIG. 24). A specific description will be given below.

First, the control unit 150 sets the level value (current level value 161) applied when picking is first performed and stores it in the storage unit 152. Here, the current level value 161 is set to level 4 of the parameter table 159 of Table 1. In addition, this setting and each step of the flow of FIG. 22 are performed by the control unit 150 functioning as a setting unit. However, the control of the pickup action of the semiconductor die 15 is controlled by the control unit 150 as the pickup control unit. Meta comes into play. In step S100 of FIG. 22, the control unit 150 initializes the variable n to zero. The variable n is a variable that counts the number of wafers that have been picked. Then, in step S102, wafer replacement is performed, and preparations for picking up semiconductor die 15 of a new wafer are performed. In step S104, the control unit 150 picks up the semiconductor die 15. The picking is indexed by the current level value=4, the parameter value of each peeling parameter of level 4 is read from the parameter table 159, and the parameter value of each peeling parameter read is used to pick up the semiconductor die 15. At this time, the suction air flow rate of the suction head 18 is detected by the flow sensor 106, and the suction air flow rate is input to the control unit 150. The control unit 150 (setting unit) acquires the actual flow rate change 158 which is the temporal change of the suction air flow rate, and stores it in the storage unit 152 (step S1041).

Then, in step S106, the control unit 150 calculates the correlation value (evaluation value) between the actual flow rate change 158 and the expected flow rate change 157 stored in the storage unit 152 in advance, and stores the correlation value in the storage unit 152. Then, in step S108, the control unit 150 confirms whether the pickup of all the semiconductor dies 15 of a wafer has been completed. If the pickup of all the semiconductor dies 15 of a wafer is not completed (S108: No), the pickup of the semiconductor dies 15 of S104 and the acquisition of the actual flow change 158 of S1041 and the correlation value of S106 are repeated. Figure out. If the pickup of all the semiconductor dies 15 of one wafer is completed (S108: Yes), the process proceeds to step S110.

Next, in S110, the control unit 150 adds 1 to the variable n (incremental the variable n). Then, in step S112, the control unit 150 confirms whether the variable n is a constant Y or more. The constant Y is an integer greater than 1, which specifies the wafer The number of pieces. In S112, the control unit 150 confirms whether the number of wafers picked up (variable n) has reached the number of wafers represented by the constant Y. If S112 is No, return to S102 and repeat S102 to S110. When S112 is YES, it progresses to step S114.

In S114, the control unit 150 obtains a representative correlation as a representative value of the correlation values (evaluation values) of the plurality of semiconductor dies 15 (specific semiconductor dies 15) obtained by repeatedly executing S106. Value (representing the evaluation value of crystal grains). The representative correlation value is, for example, an average value or a center value of a plurality of correlation values, but it is not limited to these, as long as it is a representative value obtained by using a known statistical process.

Next, in step S116, the control unit 150 confirms whether the representative correlation value acquired in S114 is less than the threshold value TH1. Table 2 is an example of the threshold value table 160. The threshold value table 160 is stored in the storage unit 152 in advance. The threshold value table 160 is a table in which the threshold value TH1 and the threshold value TH2 are defined for each level value, and the range of the peel easiness (related value) of the semiconductor die 15 assumed for each level value is defined. For example, level 4 as the current level value indicates the level that should be used when the ease of peeling off the semiconductor die 15 from the dicing sheet 12 (correlation value) is 0.81 (threshold value TH1) to 0.85 (threshold value TH2) Value, and if it is not in this range, it means that other grade values should be used. The threshold value TH1 and the threshold value TH2 of other grade values are also the same. The grade 1 without the threshold value TH2 indicates the grade value that should be used when the ease of peeling (related value) is 0.96 (threshold value TH1) or higher , Level 8 that does not specify the threshold TH1 indicates the value that should be used when the ease of peeling (correlation value) is 0.65 (threshold TH2) or less.

In S116, the control unit 150 reads the threshold value TH1=0.81 of level 4 as the current level value 161 from the threshold value table 160 in the storage unit 152, and confirms whether the representative correlation value is less than 0.81 (threshold value TH1 ). Then, in the case of YES in S116, in step S120, the control unit 150 increases the current level value 161 by one (changes it to a low-speed level value) to become level 5, and saves the current level value 161=5 to storage部152. This is the transition from level 4 to level 5 in the level transition diagram shown in FIG. 23. And, after S120, return to S100 again to perform processing. In this way, when the representative correlation value is less than the threshold value TH1 of level 4 (current level value 161), the actual ease of peeling of the semiconductor die 15 is lower than the ease of peeling assumed in level 4, and therefore the migration to a lower speed A level value of, to perform picking that suppresses damage to the semiconductor die 15 or picking errors.

On the other hand, when S116 is No, it progresses to step S118. In S118, the control unit 150 reads the current level value 161 as the current level value 161 from the threshold value table 160 of the level 4 threshold TH2=0.85, and confirms whether the representative correlation value is greater than 0.85 (threshold value TH2 ). Then, in the case of YES in S118, in step S122, the control unit 150 decreases the current level value 161 by one (changes it to high The speed level value) becomes level 3, and the current level value 161=3 is stored in the storage unit 152. This is the transition from level 4 to level 3 in the level transition diagram shown in FIG. 23. And, after S122, return to S100 again to perform processing. In this way, when the representative correlation value is greater than the threshold value TH2 of level 4 (current level value 161), the actual ease of peeling of the semiconductor die 15 is higher than the ease of peeling assumed in level 4. High-speed grade value to shorten the pick-up time of semiconductor die 15.

When S118 in FIG. 22 is No, the level value is not changed, and the process returns to S100 again. In this case, the actual ease of peeling of the semiconductor die 15 is within the range of ease of peeling assumed in level 4 (current level value 161). Therefore, the parameter values of each peeling parameter of level 4 are used for picking up. . The control unit 150 repeatedly performs the control of the level transition described above.

Furthermore, in the above description, in each step of S116 and S118, the representative correlation value is respectively connected with the threshold value TH1 of a level value of the threshold value table 160 (level 4 as the current level value). The limit value TH2 is compared, and a level value is increased in S120 (change to a low speed level), or a level value is decreased in S122 (change to a high speed level), or the level value is maintained. However, in each step of S116 and S118, the representative correlation value can also be compared with the threshold value TH1 and the threshold value TH2 of the threshold value table 160, and the grade value can be used in S120. The sex is increased by two or more levels, or the level value is decreased by two or more levels at once in S122, or the level value is maintained. Specifically, for example, in a case where the current level value=4, in S116, the control unit 150 compares the representative correlation value with the threshold value table in Table 2. The threshold value TH1 of 160 level 4, level 5, level 6, and level 7 are compared, and the largest level value among the level values that meet the condition (representative value <TH1) is obtained. For example, if the representative correlation value is 0.70, the largest level value among the level values satisfying the condition (representative correlation value<TH1) is obtained, that is, level 6. Then, in S120, the control unit 150 transitions the current level value 161 to level 7, which is a level value that is one higher than the level value=6 acquired in S116. This is the transition from level 4 to level 7 in the level transition diagram shown in FIG. 24. Furthermore, in the level transition diagram of FIG. 24, only the line representing the transition from level 4 to another level value is drawn, and the line for transition from another level value to a level value other than the other level value is omitted. . In addition, in the same way, for example, in the case of the current level value 161=4, in S118, the control unit 150 compares the representative correlation value with the respective thresholds of the threshold value table 160 of Table 2 for Level 4, Level 3, and Level 2. The value TH2 is compared, and the smallest level value among the level values that meet the condition (representative value>TH2) is obtained. For example, if the representative correlation value is 0.92, level 3 is acquired as the minimum level value among the level values that satisfy the condition (representative correlation value>TH2). Then, in S122, the control unit 150 transitions the current level value 161 to level 2, which is a level value that is one lower than the level value=3 acquired in S118. This is the transition from level 4 to level 2 in the level transition diagram shown in FIG. 24. If the level value can be increased by two or more levels at once, or the level value can be decreased by two or more levels at once, the level value most suitable for picking can be reached more quickly.

<Effects>

Next, the function and effect of the semiconductor die pickup system 500 described above will be described. According to the semiconductor die picking system 500 described above, half The peeling action of the conductor die 15 includes switching the opening pressure of the opening 23 provided on the adsorption surface 22 of the platform 20 between a first pressure close to a vacuum and a second pressure close to the atmospheric pressure. The peeling operation can reliably suppress damage to the semiconductor die 15 during pickup or pickup errors.

In addition, when the semiconductor die picking system 500 described above picks up a specific semiconductor die 15 (in the flow of FIG. 22, each semiconductor die 15 of one or more wafers), the suction head 18 is drawn. Time change of suction air flow (actual flow change 158). Furthermore, based on the acquired actual flow rate change 158, the level value applied when picking up other semiconductor die 15 after picking up the specific semiconductor die 15 is changed. That is, the peeling operation (parameter value of each peeling parameter (pickup parameter)) applied when picking up other semiconductor die 15 is changed. Thereby, for example, when the semiconductor die 15 is continuously picked up, when the peelability of the semiconductor die 15 from the dicing sheet 12 changes, the peeling operation (pickup operation) is changed in accordance with the change in peelability. When the peelability is deteriorated (the ease of peeling becomes low), the peeling operation is changed to further promote peeling, and therefore it is possible to reliably suppress damage to the semiconductor die 15 and picking errors. On the other hand, when the peelability becomes good (easy peeling becomes higher), it is changed to a shorter peeling operation, so the pick-up time can be shortened. In this way, it is possible to appropriately balance the suppression of damage or picking errors of the semiconductor die 15 and the acceleration of the pickup of the semiconductor die 15.

Compared with the case where the peeling action of the semiconductor die 15 to be picked up is changed in real time while checking the suction air flow rate of the suction head 18, the semiconductor die picking system 500 described above has an overwhelming advantage.

First, when the peeling action is changed in real time, when a semiconductor die 15 is picked up, (1) the detection of the suction air flow is repeated multiple times; (2) the peeling action is determined according to the detection result; (3) ) A series of processing of changing the peeling action according to the judgment result or advancing the action without changing it. If the determination of (2) is not completed, it is impossible to enter (3) (the action cannot be advanced), so picking may be delayed. Since the pickup of the semiconductor die 15 can be performed, for example, millions of pieces, the pickup delay in each semiconductor die 15 will eventually become a huge delay. On the other hand, the semiconductor die picking system 500 of the above-described embodiment detects the suction air flow rate when picking up, but this is used to pick up the semiconductor die 15 in the future, and will not affect the current picking action. Bring any impact. In other words, there is no such thing as (2) and (3) in the pick-up operation, and there is no case in which the operation cannot proceed if the determination is not completed. In this way, the pickup action can become very high-speed. In addition, in the semiconductor die pickup system 500 described above, for example, a plurality of CPUs 151 can be provided in the control unit 150, and a certain CPU 151 controls the pickup operation, and another CPU 151 simultaneously ( In the background) the actual flow rate change 158 is acquired, the correlation value is calculated based on the actual flow rate change 158, and the subsequent semiconductor die grade value based on the correlation value is acquired, which can achieve further speedup.

In addition, when the peeling operation is changed in real time, the aforementioned (1) to (3) are performed during the pickup operation, so the control becomes very complicated. On the other hand, the semiconductor die picking system 500 described above can make the control very simple.

In addition, when the peeling operation is changed in real time, it is difficult for the operator to grasp which peeling operation is applied to each semiconductor die 15 to pick up. The other party In addition, since the semiconductor die picking system 500 described above does not change the peeling operation during the picking operation, it is very easy to grasp which peeling operation is applied to each semiconductor die 15 for picking. This grasp is very important. For example, if the number of switching of the opening pressure, which is one of the peeling parameters, is increased, the semiconductor die 15 will be sufficiently peeled from the dicing sheet 12 even if it is difficult to peel off, and the occurrence of damage or pickup of the semiconductor die 15 can be suppressed. error. On the other hand, the semiconductor die 15 may be bent and deformed multiple times due to the increase in the number of switching of the opening pressure, and damage to the semiconductor die 15 may increase. For such semiconductor die 15, for example, it is preferable to actively perform crack inspection. That is, it is preferable to grasp the peeling operation applied to each semiconductor die 15 to perform quality control of each semiconductor die 15. The semiconductor die picking system 500 described above can perform this quality control very easily.

Furthermore, the advantages of the semiconductor die picking system 500 of this embodiment over the case where the peeling operation is changed in real time are described above, but this does not exclude the embodiment of changing the peeling operation in real time from the present invention. That is, in the semiconductor die picking system 500 of the present invention, it is also possible to instantly change the peeling operation of the semiconductor die 15 to be picked up while checking the suction air flow rate of the suction head 18. For example, in the semiconductor die 15 currently to be picked up, it is also possible to change the peeling operation during the actual peeling based on the actual flow rate change 158 acquired during the initial peeling.

<Class value of stripping parameters for each category>

Next, the case where the level value is set according to the type of peeling parameter will be described. The parameter table 159 of Table 1 described above prepares level values common to a plurality of types of peeling parameters. However, as shown in Table 3-1 and Table 3-2, it can also be peeled off The parameter table is prepared for the type of parameter, and the level value is prepared according to the type of the stripping parameter. In the parameter table of Table 3-1, the "number of switching times of opening pressure during initial peeling" is specified for grade A-1 to grade A-8, and in the parameter table of Table 3-2, the parameter table for "formal peeling" The number of times of switching of the opening pressure is level B-1 to level B-8. In addition, although not shown in the figure, the same parameter table is prepared for the other peeling parameters. Furthermore, the threshold value table 160 shown in Table 2 is also prepared according to the type of peeling parameter, and the threshold value TH1 and the threshold value TH2 corresponding to the level value of each peeling parameter are defined in advance. For example, corresponding to each level A-1~level A-8 in Table 3-1, prepare a threshold value table that specifies the threshold value TH1 and the threshold value TH2 as in Table 2, and compare it to Table 3-2 Corresponding to each level B-1~level B-8, prepare another threshold value table that specifies the threshold value TH1 and the threshold value TH2 as in Table 2. For other peeling parameters, the respective threshold value tables are prepared similarly. In addition, the current level value is stored in the storage unit 152 according to the type of peeling parameter.

Furthermore, in the flow of FIG. 22, in S104, the current level value of each type of peeling parameter is used as an index, and the parameter value is read from each parameter table of each type of peeling parameter to perform semiconductor die 15 Of pickup. For example, using the current level value (any level value from A-1 to A-8) regarding the "number of switching times of opening pressure during initial peeling" as an index, from the "number of switching times of opening pressure during initial peeling" In the parameter table (Table 3-1), the "number of switching times of opening pressure during initial peeling" corresponding to the current level value is read to pick up the semiconductor die 15. Similarly, using the current level value (any level value from B-1 to B-8) regarding the "number of switching times of the opening pressure at the time of regular peeling" as an index, from In the parameter table (Table 3-2), read the "number of switching times of opening pressure during actual peeling" corresponding to the current level value to pick up the semiconductor die 15.

In addition, in the flow of FIG. 22, using the threshold value table prepared according to the type of peeling parameter and the current level value of each type of peeling parameter, S116, S118, S120, and S122 are executed according to the type of peeling parameter, so that The current level value of each type of stripping parameter is migrated separately. For example, in S116 and S118, the current level value (any level value from A-1 to A-8) for the "number of switching times of the opening pressure at the initial peeling" and the value for the "opening pressure at the initial peeling" are used. The threshold value table of switching times" is indexed by the current level value, the threshold value TH1 and the threshold value TH2 are read from the threshold value table, and the threshold value TH1 and the threshold value read are performed. The value TH2 is compared with the representative correlation value. According to the comparison result, in S120 and S122, turn off The current level value (any level value from A-1 to A-8) in the "number of switching times of opening pressure during initial peeling" is transferred to another level value (any level from A-1 to A-8) value). Similarly, in S116 and S118, the current level value (any level value from B-1 to B-8) regarding the "number of switching times of the opening pressure during the actual peeling" and the "opening pressure during the actual peeling" are used. The threshold value table of the switching times" is indexed by the current level value, and the threshold value TH1 and the threshold value TH2 are read from the threshold value table, and the threshold values TH1 and the threshold values read are performed. The limit value TH2 is compared with the representative correlation value, and based on the comparison result, in S120 and S122, the current level value (any of B-1~B-8 on the number of switching times of the opening pressure at the time of official peeling) Level value) migrate to another level value (any level value from B-1 to B-8). The same is true for other stripping parameters.

If this is the case, since the current level value is managed according to the type of peeling parameter, and the low-speed level or the high-speed level is migrated according to the type of peeling parameter, it is possible to adjust the peeling parameters with more variety of peeling parameters according to the peelability of the semiconductor die 15 The combination of parameter values to pick up the semiconductor die 15.

<Level Migration Control of Another Embodiment>

Next, the rank transition control of another embodiment will be described. 25 and FIG. 26 are flowcharts showing the flow of level transition control according to another embodiment. In this embodiment, all semiconductor dies 15 are regarded as specific semiconductor dies 15, and each time one or more semiconductor dies 15 of a wafer are picked up, there is an opportunity to shift the level value. A specific description will be given below.

First, the control unit 150 will first pick up the applied level value (when The previous level value 161) is stored in the storage unit 152. Here, the current level value 161 is set to level 4 of the parameter table 159 of Table 1. In addition, this setting and each step of the flow in FIGS. 25 and 26 are performed by the control unit 150 functioning as a setting unit. However, the control of the pickup operation of the semiconductor die 15 is performed by the control unit 150 functioning as a pickup control unit. In step S200 of FIG. 25, the control unit 150 initializes the variable n1 and the variable n2 to zero. Variable n1 and variable n2 are variables that count the number of wafers. Then, in step S202, the wafer is replaced, and the semiconductor die 15 of the new wafer is prepared for pickup. In step S204, the control unit 150 initializes the variable m1 and the variable m2 to zero. The variable m1 is a variable that counts the number of semiconductor dies 15 that are detected as difficult to peel (the number of difficult to peel detections) in a wafer, and the variable m2 is a variable that counts the semiconductor dies that are detected as easily peeled in a wafer The number of 15 (easy peel detection number) is a variable that counts.

Next, in step S206, the control unit 150 picks up the semiconductor die 15. The picking is indexed by the current level value=4, the parameter value of each peeling parameter is read from the parameter table 159, and the read parameter value is used to pick up the semiconductor die 15. At this time, the suction air flow rate of the suction head 18 is detected by the flow sensor 106, and the suction air flow rate is input to the control unit 150. The control unit 150 (setting unit) acquires the actual flow rate change 158 which is the temporal change of the suction air flow rate, and stores it in the storage unit 152 (step S2061). Then, in step S208, the control unit 150 calculates the correlation value (evaluation value) between the actual flow rate change 158 and the expected flow rate change 157 stored in the storage unit 152 in advance, and stores the correlation value in the storage unit 152.

Then, in step S210, the control unit 150 confirms that the Whether the relevant value of is lower than the threshold TH1 (the twelfth prescribed value). The threshold TH1 is the threshold TH1 specified in the threshold table 160 shown in Table 2, where the current level value 161, that is, the threshold value of level 4 TH1=0.81 is used here. If S210 is YES, in step S212, the control unit 150 adds 1 to the variable m1 (the number of detections for difficult peeling) (increments the variable m1). If S210 is no, the control unit 150 does not execute S212 and proceeds to step S214.

In S214, the control unit 150 confirms whether the correlation value calculated in S208 is higher than the threshold value TH2 (the eleventh predetermined value). The threshold TH2 is the threshold TH2 specified in the threshold table 160 shown in Table 2, where the current level value 161, that is, the threshold value of level 4 TH2=0.85 is used. If S214 is YES, in step S216, the control unit 150 adds 1 to the variable m2 (the number of easy peeling detections) (increments the variable m2). If S214 is no, the control unit 150 does not execute S216 and proceeds to step S218.

In S218, the control unit 150 confirms whether the pickup of all the semiconductor dies 15 of a wafer has been completed. If the pickup of all the semiconductor dies 15 of a wafer is not completed (S218: No), S206 to S216 are repeated, and if it is completed (S218: Yes), then go to step S220 in FIG. 26.

In S220 of FIG. 26, the control unit 150 confirms whether the variable m1 (the number of difficult peel detections) is greater than the constant Q. The constant Q is an integer greater than 0. In the case of YES in S220, the control unit 150 initializes the variable n2 to 0 in step S224. Then, in step S226, the control unit 150 adds 1 to the variable n1 (increments the variable n1). In this way, the variable n1 counts the number of wafers satisfying the condition of S220. Then, in step S228, the control unit 150 confirms whether the variable n1 is greater than the constant Y1. constant Y1 is an integer of 0 or more. In S228, it is confirmed whether the number of wafers (variable n1) satisfying the condition of S220 is greater than the predetermined number (constant Y1). If S228 is YES, in step S230, the control unit 150 increases the current level value 161 by one (changes to a low-speed level value) to become level 5, and stores the current level value=5 in the storage unit 152. Then, in step S240, the control unit 150 initializes the variable n1 and the variable n2 to zero. Furthermore, after S240, it returns to S202 of FIG. 25 again to repeat the process. In this way, if the number of wafers (variable n1) that meets the condition of S220 (the number of difficult-to-peel detections m1 per wafer is greater than the constant Q) is greater than the predetermined number (constant Y1), it is judged as actual The ease of peeling of the semiconductor die 15 is lower than that assumed in level 4, and it migrates to a lower speed level value to perform picking that suppresses damage to the semiconductor die 15 or picking errors. If S228 is No, the level value is not changed, and the process is repeated by returning to S202 of FIG. 25 again.

On the other hand, if S220 is No, it progresses to step S222. In S222, the control unit 150 confirms whether the variable m2 (the number of easy peeling detections) is more than the constant P. The constant P is an integer greater than 0. If S222 is YES, the control unit 150 initializes the variable n1 to 0 in step S232. Then, in step S234, the control unit 150 adds 1 to the variable n2 (increments the variable n2). In this way, the variable n2 counts the number of wafers satisfying the condition of S222. Then, in step S236, the control unit 150 confirms whether the variable n2 is greater than the constant Y2. The constant Y2 is an integer greater than 0. In S236, it is confirmed whether the number of wafers satisfying the condition of S222 (variable n2) is greater than the predetermined number (constant Y2). If S236 is yes, then in step S238, control The control unit 150 reduces the current level value 161 by one (changes to a high-speed level value) to become level 3, and stores the current level value=3 in the storage unit 152. Then, in S240, the control unit 150 initializes the variable n1 and the variable n2 to zero. Furthermore, after S240, it returns to S202 of FIG. 25 again to repeat the process. In this way, if the number of wafers (variable n2) satisfying the condition of S222 (the number of easy peeling detections per wafer m2 is greater than the constant P) is greater than the predetermined number (constant Y2), it is judged as actual The ease of peeling of the semiconductor die 15 is higher than that assumed in level 4 (the current level value), and it migrates to a higher speed level value to shorten the pick-up time of the semiconductor die 15. In the case of No in S222 and in the case of No in S236, the level value is not changed, and the processing is repeated by returning to S202 of FIG. 25 again.

In the above-described embodiment, it is also possible to reliably suppress the damage of the semiconductor die 15 when picking up the semiconductor die 15, and when picking up a plurality of semiconductor die 15 continuously, it is possible to suppress the damage of the semiconductor die 15 The balance with the acceleration of the pickup of the semiconductor die 15 is appropriate.

<other>

In the above-described embodiments, the actual flow rate change 158 is acquired for all the semiconductor die 15. That is, all the semiconductor crystal grains 15 are regarded as specific semiconductor crystal grains 15. However, the semiconductor die 15 (the specific semiconductor die 15) that obtains the actual flow rate change 158 may not be all semiconductor die 15. For example, one or more semiconductor dies 15 in a wafer can also be used as specific semiconductor dies 15.

In addition, in each of the embodiments described above, one piece of Or the semiconductor die 15 of multiple wafers gives the opportunity to shift the level value. However, it is also possible to give an opportunity to shift the level value every time one semiconductor die 15 is picked up or every time a plurality of semiconductor die 15 are picked up. For example, when a plurality of semiconductor dies 15 are picked up sequentially, the greater the variation (or assumed variation) of the peelability of the semiconductor dies 15 is, the more frequently the opportunity to shift the level value is given.

In addition, in each of the above-described embodiments, since the semiconductor die 15 just after picking up the specific semiconductor die 15 (the semiconductor die 15 with the actual flow rate change 158), the new level value is applied for picking . However, it is also possible to pick up a predetermined number of semiconductor dies 15 after picking up a specific semiconductor die 15 and then apply a new level value to pick up the semiconductor die 15. Furthermore, in this specification, the so-called "pick up of other semiconductor die 15 after picking up the specific semiconductor die 15" does not only mean "pick up of the semiconductor die 15 just after picking up the specific semiconductor die 15" "It also includes the pickup of the semiconductor die 15 after the pickup of the predetermined number of semiconductor die 15 as described above.

As described above, the semiconductor die 15 that is picked up by increasing the number of switching of the opening pressure may be more damaged than other semiconductor die 15. Therefore, the semiconductor die 15 that has undergone switching of the opening pressure more than a predetermined number of times when the semiconductor die 15 is picked up may be used as a target for crack inspection or the like. For example, the suction head 18 transports the semiconductor die 15 that has undergone switching of the opening pressure more than a predetermined number of times to a place different from other semiconductor die 15 (inspection module, inspection unit for crack inspection, etc.), using the inspection module Wait to check whether there are cracks and deflection in the semiconductor die 15.

In addition, in each of the embodiments described above, the period during which the expected flow rate change 157 and the actual flow rate change 158 are compared to obtain the correlation value (evaluation value) is the predetermined period in the initial peeling. However, the period during which the expected flow rate change 157 and the actual flow rate change 158 are compared may be the entire period of the initial peeling, or the entire period of the formal peeling, or the prescribed period in the formal peeling, or the period of combining the initial peeling and the formal peeling. Wait. The expected flow rate change 157 is stored in the storage unit 152 in advance only during the period when compared with the actual flow rate change 158.

In addition, in the embodiment described above, as an index for grasping the peelability of the semiconductor die 15, the correlation value between the actual flow rate change and the expected flow rate change is obtained. The correlation value takes a value from 0 to 1.0. The larger the value, the easier it is for the semiconductor die 15 to peel off from the dicing sheet 12, which can be called the ease of peeling. On the other hand, the value after subtracting the correlation value from 1.0 (1.0-correlation value) takes a value from 0 to 1.0. The larger the value, the more difficult it is for the semiconductor die 15 to peel from the dicing sheet 12, which can be called the peeling difficulty. . As an index (evaluation value) of the peelability of the semiconductor crystal grains 15, the peel difficulty may be used instead of the correlation value (easy to peel). In the embodiment described above, the threshold value table 160 of Table 2 on the premise of the correlation value (easiness of peeling) and the value range of the correlation value (0 to 1.0) is used (the lower the grade value, the The larger the threshold TH1 and the threshold TH2 are set). However, it is also possible to use the threshold value table 160 based on the peel difficulty (1.0-related value) and the value range of the peel difficulty (0 to 1.0) (the lower the grade value, the smaller the threshold value is set). Table of limit value TH1 and threshold value TH2). In addition, the ease of peeling or the difficulty of peeling may also be referred to as the peeling degree.

In addition, in the peeling operation described above, during the initial peeling and the actual peeling, the suction pressure of the suction surface 22 of the platform 20 is maintained at the third pressure P ₃ close to the vacuum. However, during the initial peeling, the final peeling, or the initial peeling and the final peeling, it can also be set to switch between the third pressure P ₃ close to vacuum and the fourth pressure P ₄ close to atmospheric pressure one or more times. pressure. As one of release parameters, also additional "switching times adsorption pressure" means pressure switching times and the fourth adsorption pressure surface 22 of the platform 20 between the third pressure P _{3 4} P i.e., to the semiconductor die and The worse the peelability of 15 is, the more "the number of times of switching the suction pressure" is increased to promote the peeling of the semiconductor die 15 from the dicing sheet 12.

The semiconductor die pickup system 500 can also be referred to as a semiconductor die pickup device. In addition, the semiconductor die picking system 500 may be a part of a bonding device (bonding machine, bonding system) or a die bonding device (die bonding machine, die bonding system), and may also be referred to by these names.

<Notes>

In addition, the first, third, fifth, seventh, and ninth prescribed values described in "Means for Solving Problems" correspond to those related to the representative in S118 of the flow of FIG. 22 Value (representing the evaluation value of the crystal grain) is the threshold TH2 for comparison. Similarly, the second, fourth, sixth, eighth, and tenth prescribed values described in "Means for Solving Problems" correspond to those related to the representative in S116 of the flow in FIG. 22 Value (representing the evaluation value of the crystal grain) is the threshold TH1 for comparison.

The various embodiments of the present invention have been described above, but the present invention is not limited to the various embodiments described above, and of course it can be possible without departing from the spirit of the present invention. Implemented in various ways within the scope.

10: Wafer holder

12: cut sheet

12a, 18a: surface

12b: back

13: Ring

14: gap/cut into gap

15: Semiconductor die

16: expansion ring

17: Ring pressing part

18: Suction head

19: Suction hole

20: platform

22: Adsorption surface

23: opening

24: base body

26: Slot

27: Adsorption hole

28: Inside the upper side

30: moving components

80: Opening pressure switching mechanism

81, 91, 101: Three-way valve

82, 92, 102: drive unit

83~85, 93~95, 103~105: Piping

90: Adsorption pressure switching mechanism

100: suction mechanism

106: Flow sensor

110: Wafer holder horizontal drive part

120: Platform up and down direction drive unit

130: Suction head drive

140: vacuum device

150: Control Department

151: CPU

152: Storage Department

153: Device/Sensor Interface

154: Data Bus

155: Control Program

156: Control Data

157: Expect traffic changes

158: Actual flow change

159: parameter table

160: Threshold Limit Table

161: current level value

300: Step difference surface forming mechanism

400: Driving part of step surface forming mechanism

500: Picking system for semiconductor die

a: arrow

Claims (21)

A pickup system for semiconductor crystal grains, which picks up semiconductor crystal grains attached to the surface of a dicing sheet from the dicing sheet. The semiconductor crystal grain pickup system is characterized in that it includes: a suction head for adsorbing the semiconductor crystal A suction mechanism, which is connected to the suction head, sucks air from the surface of the suction head; a flow sensor, which detects the flow of suction air sucked by the suction mechanism; a platform, which includes the suction Cutting the suction surface of the back surface of the sheet; an opening pressure switching mechanism that switches the opening pressure of the opening of the suction surface provided on the platform between a first pressure close to vacuum and a second pressure close to atmospheric pressure; and a setting unit When the semiconductor die is picked up, the pickup parameter including the number of switching times of the opening pressure is set, and the setting unit obtains the suction air detected by the flow sensor when the semiconductor die is picked up. The time change of the flow rate is the flow rate change, and based on the flow rate change, an evaluation value for evaluating the peelability of the semiconductor crystal grains from the dicing sheet is calculated, and based on the evaluation value, the pickup of the semiconductor crystal is changed The picking parameters when picking up other semiconductor die after the pellet. The semiconductor die picking system described in claim 1, wherein the setting unit changes the holding of the opening pressure at the first pressure when picking up the other semiconductor die based on the evaluation value time. The semiconductor die picking system described in the scope of the patent application further includes: a plurality of moving elements arranged in the opening, and the front end surfaces of the plurality of moving elements are higher than the suction surface Move between a first position and a second position lower than the first position. When picking up the semiconductor die, the plurality of moving elements are moved sequentially from the first position to the first position at predetermined time intervals. The second position, or the movement from the first position to the second position at the same time by a predetermined combination of the moving elements, and the setting unit changes the pickup of the other semiconductor die based on the evaluation value The specified time of the hour. The semiconductor die picking system described in claim 3, wherein the setting unit changes the movement from the first position to the first position while picking up the other semiconductor die based on the evaluation value. The number of said moving elements in the second position. The semiconductor die picking system described in claim 3 or 4, wherein when picking up the semiconductor die, the opening pressure is switched between the first pressure and the second pressure , To perform the initial peeling of the dicing sheet sucked through the opening from the semiconductor die, and the flow rate change is the suction detected by the flow sensor during the initial peeling Time change of air flow. The semiconductor die picking system described in item 5 of the scope of patent application System, wherein the number of switching is the number of switching the opening pressure between the first pressure and the second pressure during the initial peeling. The semiconductor die picking system described in claim 1 or 2, wherein the setting unit changes the self-determination when the other semiconductor die is peeled from the dicing sheet based on the evaluation value. The suction head landed on the semiconductor die and waited until the semiconductor die started to be lifted. The semiconductor die picking system described in the first or second patent application includes a storage unit for storing expected flow rate changes, and the expected flow rate change is that the semiconductor die is removed from the dicing sheet well. The time change of the suction air flow rate when the semiconductor die is picked up in the case of material pickup, and the setting unit is based on the difference between the flow rate change and the expected flow rate change when the semiconductor die is picked up To find the evaluation value. The semiconductor die picking system described in item 1 or item 2 of the scope of patent application further includes: an inspection unit that performs crack inspection of the semiconductor die, and will pick up the semiconductor die. The semiconductor crystal grains that have been switched over a predetermined number of times are subject to crack inspection. For the semiconductor die picking system described in item 1 or item 2, the setting unit obtains the flow rate change of the semiconductor die constituting one or more wafers, and based on each of the The flow rate changes to obtain the evaluation value, Based on a plurality of the evaluation values, the picking parameter when picking up the other semiconductor die is changed. The semiconductor die picking system described in item 1 or item 2 of the scope of the patent application includes: a storage section that stores a table of parameter values of the picking parameters that have a corresponding relationship with a plurality of level values, and current The applied level value of the parameter value of the picking parameter is the current level value, using the current level value as an index, reading the parameter value of the picking parameter from the table, and applying the parameter of the picking parameter Pick up the semiconductor die based on the value, and the setting unit shifts the current level value to another level value based on the evaluation value, thereby changing the parameter value of the picking parameter when picking up the other semiconductor die . The semiconductor die picking system described in claim 1 or 2, wherein the semiconductor die for which the evaluation value is calculated is a specific semiconductor die, and the setting unit is based on one or more For the evaluation value of the specific semiconductor crystal grain, a representative crystal grain evaluation value that is a representative value of the evaluation value is obtained, and when the representative crystal grain evaluation value is higher than the first predetermined value, when the In the case of the other semiconductor die, the number of switching times is reduced compared to the number of switching times when the specific semiconductor die is picked up, and when the evaluation value of the representative die is lower than the second predetermined value, When picking up the other semiconductor die, it is different from the cut when picking up the specific semiconductor die. Compared with the number of switching times, the number of switching times is increased, and the second predetermined value is a value lower than the first predetermined value. The semiconductor die picking system described in the scope of patent application 2, wherein the semiconductor die for which the evaluation value is calculated is a specific semiconductor die, and the setting unit is based on one or more of the specific semiconductor The evaluation value of the crystal grain, the representative crystal grain evaluation value as the representative value of the evaluation value is obtained, and when the representative crystal grain evaluation value is higher than the third predetermined value, when the other semiconductor crystal is picked up When picking up the specific semiconductor die, the time is shortened compared to the time for maintaining the opening pressure at the first pressure when picking up the specific semiconductor die, and the representative die evaluation value is lower than the fourth rule In the case of the value, when the other semiconductor die is picked up, the time is prolonged compared to the time for maintaining the opening pressure at the first pressure when the specific semiconductor die is picked up, so The fourth predetermined value is a value lower than the third predetermined value. The semiconductor die picking system described in claim 3, wherein the semiconductor die for which the evaluation value is calculated is a specific semiconductor die, and the setting unit is based on one or more of the specific semiconductor The evaluation value of the crystal grain, the representative crystal grain evaluation value as the representative value of the evaluation value is obtained, and when the representative crystal grain evaluation value is higher than the fifth predetermined value, when the other semiconductor crystal is picked up When picking up the specific semiconductor die, the predetermined time is shortened compared to the predetermined time when picking up the specific semiconductor die. When the evaluation value of the representative die is lower than the sixth predetermined value, when the For other semiconductor dies, the rules for picking up the specific semiconductor die The predetermined time is extended compared to the predetermined time, and the sixth predetermined value is a value lower than the fifth predetermined value. The semiconductor die picking system described in claim 4, wherein the semiconductor die for which the evaluation value is calculated is a specific semiconductor die, and the setting unit is based on one or more of the specific semiconductor The evaluation value of the crystal grain, the representative crystal grain evaluation value as the representative value of the evaluation value is obtained, and when the representative crystal grain evaluation value is higher than the seventh predetermined value, when the other semiconductor crystal is picked up When picking up the specific semiconductor die, the number of moving elements is increased compared to the number of moving elements that move from the first position to the second position while picking up the specific semiconductor die. When the representative die evaluation value is lower than the eighth prescribed value, when picking up the other semiconductor die, it moves from the first position to the second position while picking up the specific semiconductor die Compared with the number of the moving elements, the number of the moving elements is reduced, and the eighth prescribed value is lower than the seventh prescribed value. The semiconductor die picking system described in claim 7 wherein the semiconductor die for which the evaluation value is calculated is a specific semiconductor die, and the setting unit is based on one or more of the specific semiconductor The evaluation value of the crystal grain, the representative crystal grain evaluation value as the representative value of the evaluation value is obtained, and when the representative crystal grain evaluation value is higher than the ninth predetermined value, when the other semiconductor crystal is picked up When the specific semiconductor die is picked up, the standby time is shortened compared to the standby time when the specific semiconductor die is picked up, In the case where the evaluation value of the representative die is lower than the tenth predetermined value, when the other semiconductor die is picked up, the standby time is compared with the standby time when the specific semiconductor die is picked up. When the time is extended, the tenth prescribed value is lower than the ninth prescribed value. The semiconductor die picking system described in item 1 or item 2 of the scope of patent application, wherein the semiconductor die for which the evaluation value is calculated is a specific semiconductor die, and the setting unit sets one or more The evaluation values of the specific semiconductor die are respectively compared with the eleventh predetermined value, the number of the evaluation values higher than the eleventh predetermined value, that is, the easy peeling detection number, is calculated, and one or more The evaluation values of each of the specific semiconductor crystal grains are respectively compared with a twelfth predetermined value, and the number of the evaluation values lower than the twelfth predetermined value, that is, the number of detections for difficult peeling, is obtained. The twelve predetermined value is a value lower than the eleventh predetermined value, and based on the number of easy peeling detections and the difficult peeling detection number, the value of the other semiconductor die after picking up the specific semiconductor die is changed The number of times of switching when picking. The semiconductor die picking system described in the second item of the patent application, wherein the semiconductor die for which the evaluation value is calculated is a specific semiconductor die, and the setting unit sets one or more of the specific semiconductor The evaluation values of the crystal grains are respectively compared with the eleventh predetermined value, and the number of the evaluation values higher than the eleventh predetermined value, that is, the number of easy peeling detections, is obtained, The evaluation value of one or more of the specific semiconductor crystal grains is compared with a twelfth predetermined value, and the number of evaluation values lower than the twelfth predetermined value is determined, that is, the detection of difficult peeling The twelfth predetermined value is a value lower than the eleventh predetermined value, and based on the easy-peel detection number and the hard-peel detection number, the number after picking up the specific semiconductor die is changed The time during which the opening pressure is maintained at the first pressure when picking up other semiconductor dies. The semiconductor die picking system described in claim 3, wherein the semiconductor die for which the evaluation value is calculated is a specific semiconductor die, and the setting unit sets one or more of the specific semiconductor The evaluation values of the crystal grains are respectively compared with the eleventh predetermined value, the number of the evaluation values higher than the eleventh predetermined value, that is, the easy peeling detection number, is calculated, and one or more of the specific The evaluation values of the semiconductor crystal grains are respectively compared with the twelfth predetermined value, and the number of the evaluation values that are lower than the twelfth predetermined value, that is, the number of difficult peeling detections, is obtained, and the twelfth predetermined value For a value lower than the eleventh predetermined value, based on the number of easy peeling detections and the number of difficult peeling detections, the pickup of the other semiconductor die after the specific semiconductor die is picked up is changed The stated time. The semiconductor die picking system described in claim 4, wherein the semiconductor die for which the evaluation value is calculated is a specific semiconductor die, and the setting unit sets one or more of the specific semiconductor The evaluation of the die The values are respectively compared with the eleventh predetermined value, the number of the evaluation values higher than the eleventh predetermined value, that is, the easy peeling detection number, is calculated, and the total value of one or more of the specific semiconductor die The evaluation values are respectively compared with the twelfth predetermined value, and the number of the evaluation values lower than the twelfth predetermined value, that is, the number of difficult peeling detections, is obtained, and the twelfth predetermined value is lower than the first A value of eleven a predetermined value, based on the number of easy-to-peel detections and the number of difficult-to-peel detections, to change the number of the moving elements during pickup of the other semiconductor die after the specific semiconductor die is picked up. The semiconductor die picking system described in claim 7 wherein the semiconductor die for which the evaluation value is calculated is a specific semiconductor die, and the setting unit sets one or more of the specific semiconductor The evaluation values of the crystal grains are respectively compared with the eleventh predetermined value, the number of the evaluation values higher than the eleventh predetermined value, that is, the easy peeling detection number, is calculated, and one or more of the specific The evaluation values of the semiconductor crystal grains are respectively compared with the twelfth predetermined value, and the number of the evaluation values that are lower than the twelfth predetermined value, that is, the number of difficult peeling detections, is obtained, and the twelfth predetermined value For a value lower than the eleventh predetermined value, based on the number of easy peeling detections and the number of difficult peeling detections, the pickup of the other semiconductor die after the specific semiconductor die is picked up is changed The standby time.

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