JP2018186194A - Substrate removal method and substrate removal apparatus - Google Patents

Abstract

A method and an apparatus for detaching a substrate from a holding table that adsorbs and retains the substrate while more reliably avoiding breakage or damage of the substrate, such as a wafer, are provided. A restraining member having a flat surface is brought close to a wafer held by suction on a holding table. The gas A is supplied to the gap between the holding table 7 and the wafer W while the flat surface 70a is close to the wafer W. Since the depressurized state of the gap is eliminated by the supply of the gas A, the holding force of the holding table 7 on the wafer W is reliably reduced. Further, the upward movement of the wafer W due to the ejection of the gas A from the flow holes 73 of the flow path 74 is suppressed by the flattened surface 70a of the suppression member 70. Therefore, it is possible to prevent the wafer W from being delayed due to the remaining decompressed state, and to prevent a situation in which the wafer W is partially protruded due to the uneven pressing force of the gas A and the wafer W is deformed or damaged. [Selection diagram] FIG.

Description

  The present invention relates to a substrate detachment method and a substrate detachment apparatus for detaching a substrate on which a predetermined process has been performed from a holding table that holds the substrate by suction.

  When manufacturing chip parts from substrates equipped with electronic circuits, particularly semiconductor wafers (hereinafter referred to as “wafers” where appropriate), a circuit pattern is formed on the wafer surface, and then a protective adhesive tape is applied to the wafer surface. After being attached, the back surface is polished and thinned. Before peeling the protective tape from the wafer that has undergone the backside polishing process and transporting it to the dicing process, the wafer is bonded and held to the ring frame via a supporting adhesive tape (dicing tape) in order to reinforce the wafer.

  When performing various processes such as adhesive tape pasting and dicing on a thinned wafer, the wafer is placed on a holding table such as a chuck table and the lower surface of the wafer is removed by vacuum suction or the like. It is common to perform various treatments while adsorbing and holding in a wide range. After performing various processes, the wafer is detached from the holding table and transferred to a predetermined position.

  In a general configuration in which the vacuum suction by simply holding the holding table is stopped and then the wafer is released, a reduced pressure region may remain between a part of the lower surface portion of the wafer and the holding table. In this case, a separation delay occurs in a part of the wafer due to the remaining decompression region, and as a result, the wafer may be damaged.

  In view of this, a method has been proposed in which suction by the holding table is stopped after various processes are completed and gas is supplied between the holding table and the lower surface portion of the wafer to release the wafer while eliminating the reduced pressure region. . In the separation method, gas is supplied by ejecting gas from one or more injection holes provided in the holding table (see, for example, Patent Document 1).

JP 2005-109157 A

  However, the conventional apparatus has the following problems.

  In the conventional detachment method according to Japanese Patent Application Laid-Open No. 2004-228561, a pressing force acts on the wafer non-uniformly by ejecting gas from the ejection holes. That is, since the wafer is particularly strongly pushed up around the injection hole, there is a concern that the wafer is deformed and broken due to the non-uniform pressing force. In particular, when the strength of the wafer is reduced by dicing processing or stealth dicing processing, a shearing force is generated by gas injection, and the wafer is easily torn at a dicing portion or the like. As a result, problems such as breakage of the wafer and dissipation of a part of the wafer are remarkably generated.

  The present invention has been made in view of such circumstances, and the substrate can be detached from the holding table that holds the substrate of the wafer as an example while avoiding breakage or damage of the wafer more reliably. It is a main object of the present invention to provide a substrate removal method and a substrate removal apparatus that can be used.

In order to achieve such an object, the present invention has the following configuration.
That is, the present invention is a substrate detachment method for detaching the substrate from a holding table that holds the substrate by suction,
Proximity process that has a flat surface and suppresses the substrate close to or abuts the substrate, and maintains the distance between the substrate and the flat surface at a predetermined value,
A gas supply process for supplying a gas so as to reduce the holding force of the holding table between the substrate and the holding table in a state where the suppression member is close to or in contact with the substrate;
A detaching process for detaching the substrate from the holding table;
It is characterized by providing.

  (Operation / Effect) According to this configuration, gas is supplied between the substrate and the holding table so as to reduce the holding force of the holding table. In the region where the pressure is reduced between the holding table that is sucked and held, the reduced pressure state is surely eliminated by the supply of gas. Therefore, when the substrate is detached from the holding table, it is possible to avoid the separation delay due to the remaining decompressed region. That is, it is possible to prevent the substrate from being deformed and damaged due to the delay of separation.

  Further, the gas is supplied in such a manner that the holding force of the holding table is reduced between the substrate and the holding table in a state where the suppressing member having a flat surface is brought close to or in contact with the substrate. In this case, when the gas is supplied, the substrate is quickly suppressed by the flat surface of the suppression member, thereby preventing a part of the substrate from protruding upward due to the uneven pressing force of the supplied gas. it can. Therefore, it is possible to detach the substrate from the holding table having a reduced holding force while more reliably avoiding the occurrence of deformation and breakage of the substrate due to the protrusion.

In the above-described invention,
It is preferable that the detachment process is performed by the suppression member being detached from the holding table together with the substrate in a state where the suppression member is holding the substrate. In this case, since both the suppression of the substrate and the removal of the substrate can be continuously performed by the suppression member having the holding function, the processing time can be shortened and the apparatus configuration can be simplified.

  In the above-described invention, the predetermined value is preferably 0.5 mm or less. In this case, since the suppression member is sufficiently close to or in contact with the substrate, even when the substrate is pressed upward by the supplied gas, the substrate is quickly suppressed by the suppression member. Therefore, deformation and breakage of the substrate due to non-uniform gas pressure can be avoided more reliably.

In order to achieve such an object, the present invention may take the following configurations.
That is, the substrate detachment apparatus according to the present invention includes a holding table for mounting and holding a substrate, a suction mechanism provided on the holding table for sucking and holding the substrate by the holding table, and a flat surface. A restraining member for restraining, a proximity mechanism for performing control to bring the restraining member close to or in contact with the substrate and maintain a distance between the flat surface and the substrate at a predetermined value, and the restraining member Gas supply means for supplying gas so as to reduce the holding force of the holding table between the holding table and the substrate in the state of being in proximity to or in contact with the substrate. .

  (Operation / Effect) According to this configuration, the gas supply means for supplying the gas so as to reduce the holding force of the holding table is provided between the substrate and the holding table. In the region where the pressure is reduced between the holding table that is sucked and held, the reduced pressure state is surely eliminated by the supply of gas. Therefore, when the substrate is detached from the holding table, it is possible to avoid the separation delay due to the remaining decompressed region. That is, it is possible to prevent the substrate from being deformed and damaged due to the delay of separation.

  Further, the gas is supplied in such a manner that the holding force of the holding table is reduced between the substrate and the holding table in a state where the suppressing member having a flat surface is brought close to or in contact with the substrate. In this case, when the gas is supplied, the substrate is quickly suppressed by the flat surface of the suppression member, thereby preventing a part of the substrate from protruding upward due to the uneven pressing force of the supplied gas. it can. Therefore, it is possible to detach the substrate from the holding table having a reduced holding force while more reliably avoiding the occurrence of deformation and breakage of the substrate due to the protrusion.

  In the above-described invention, the restraining member is provided with a holding mechanism that holds the substrate on the restraining member, and the restraining member holds the substrate and detaches from the holding table whose holding force is reduced. It is preferable that the substrate is detached from the holding table. In this case, since both the suppression of the substrate and the removal of the substrate can be continuously performed by the suppression member having the holding mechanism, the processing time can be shortened and the apparatus configuration can be simplified.

  In the above-described invention, it is preferable that the flat surface is wider than the substrate, and the proximity mechanism causes the restraining member to approach or abut so that the flat surface faces the substrate. In this case, since the flat surface uniformly abuts against the entire surface of the substrate, it is possible to reliably avoid a situation in which the repulsive force acts on the substrate unevenly when the substrate is restrained by the restraining member. Therefore, it is possible to more reliably prevent the substrate from being deformed or damaged.

  In the above-described invention, the holding table has a frame holding portion for holding a ring frame, and affixing an adhesive tape across the ring frame and the substrate held on the holding table to create a mount frame It is preferable to provide a mechanism.

  (Operation / Effect) According to this configuration, after the mounting frame is created by applying the adhesive tape across the substrate and the ring frame, the gas is supplied in the state where the restraining member is brought close, and the holding table is held on the substrate. Reduce power. Since the reduced pressure state between the substrate and the holding table can be reliably eliminated while suppressing the substrate by the suppressing member, it is possible to more reliably avoid the deformation and breakage of the substrate in the produced mount frame. Therefore, a more preferable mounting frame creation process can be executed.

  In the above-described invention, the predetermined value is preferably 0.5 mm or less. In this case, since the suppression member is sufficiently close to the substrate, the substrate is quickly suppressed by the suppression member even when the substrate is pressed upward by the supplied gas. Therefore, deformation and breakage of the substrate due to non-uniform gas pressure can be avoided more reliably.

  According to the substrate detachment method and the substrate detachment apparatus of the present invention, the substrate can be detached from the holding table that holds the substrate by suction while more reliably avoiding the breakage or damage of the substrate.

It is a top view which shows the whole structure of the wafer mount apparatus which concerns on an Example. It is a front view which shows the whole structure of the wafer mount apparatus which concerns on an Example. It is a front view of the wafer conveyance mechanism which concerns on an Example. It is a top view which shows the principal part of the wafer conveyance mechanism which concerns on an Example. It is a front view of the frame conveyance mechanism which concerns on an Example. It is a figure which shows the structure of the holding table which concerns on an Example. (A) is a top view, (b) is a longitudinal cross-sectional view. It is a top view of the adhesive tape sticking part which concerns on an Example. It is a front view of the adhesive tape sticking part which concerns on an Example. It is a front view of the suppression mechanism which concerns on an Example. It is a flowchart of each process concerning an example. (A) is a flowchart explaining the outline | summary of operation | movement of a wafer mounting apparatus, (b) is a flowchart explaining the detail of the wafer removal process which concerns on step S6. It is a longitudinal cross-sectional view which shows operation | movement of step S1 and step S2 which concerns on an Example. It is a longitudinal cross-sectional view which shows operation | movement of step S3 which concerns on an Example. It is a longitudinal cross-sectional view which shows operation | movement of step S3 which concerns on an Example. It is a longitudinal cross-sectional view which shows operation | movement of step S4 which concerns on an Example. It is a longitudinal cross-sectional view which shows operation | movement of step S5 which concerns on an Example. It is a longitudinal cross-sectional view which shows operation | movement of step S6-2 based on an Example. It is a longitudinal cross-sectional view which shows operation | movement of step S6-3 based on an Example. It is a longitudinal cross-sectional view which shows operation | movement of step S6-4 based on an Example. It is a longitudinal cross-sectional view which shows operation | movement of step S6-5 which concerns on an Example. It is a figure explaining the problem of the prior art example which does not have a gas supply process. (A) is a figure which shows the state which discharge | emits gas and adsorb | sucks and holds a wafer, (b) is a figure which shows the state where the area | region of a pressure reduction state remains after gas discharge | emission stop, (c) is pressure reduction It is a figure which shows the problem by removing a wafer in the state where the state area | region remains. It is a figure explaining the problem of the prior art example which has a gas supply process. (A) is a figure which shows the state which supplies gas, (b) is a figure which shows the state by which the area | region of a pressure-reduced state is eliminated by gas supply, (c) is a nonuniform pressing by gas supply. It is a figure which shows the state which a wafer deform | transforms due to a pressure, (d) is a figure which shows the wafer in which the half dicing process is performed, (e) is a part of wafer protruding by supply of gas. It is a figure which shows the state which is damaged. It is a figure explaining the effect by the structure of an Example. (A) is a figure which shows the state which makes a suppression member adjoin to a wafer so that a suppression member may contact | abut with a wafer, (b) is a figure which shows the state in which the wafer is suppressed by the suppression member of a proximity | contact state. . It is a figure explaining the structure of a modification. (A) is a figure which shows the state which brings a suppression member close to a wafer so that a small distance may be left between a suppression member and a wafer, (b) It is a figure which shows the state which is supplying the gas suitably between holding | maintenance tables. It is a figure explaining operation | movement of the transfer process of the adhesive tape which concerns on a modification. (A) is a longitudinal cross-sectional view which shows the state which cut | disconnects the support tape previously affixed on the lower surface of a wafer along the external shape of a wafer, (b) is new support over a new ring frame and the upper surface of a wafer. It is a longitudinal cross-sectional view which shows the state which affixes a tape, (c) is a longitudinal cross-sectional view which shows the operation | movement which supplies gas in the state which made the suppression member adjoin to the wafer. It is a longitudinal cross-sectional view explaining the process of step S6-2 based on the modification using the wafer to which the adhesive tape is not affixed. FIG. 10 is a longitudinal sectional view showing an operation of detaching the wafer together with the restraining member in the modification including the restraining member having the suction holding function. It is a perspective view which shows the whole structure of a mount frame.

<Description of overall configuration>
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view showing an overall configuration of a wafer mount apparatus including a substrate removing apparatus according to an embodiment, and FIG. 2 is a front view of the wafer mount apparatus. In this embodiment, the “left-right direction”, “front-rear direction”, and “up-down direction” are determined based on the front view of the wafer mount apparatus, and correspond to the directions indicated by the symbols x, y, and z, respectively. And In this embodiment, a structure using a semiconductor wafer as an example of a substrate will be described.

  As shown in FIG. 27, this wafer mount apparatus has a pressure sensitive adhesive tape (hereinafter referred to as “hereinafter referred to as“ wafer ”) over the back surface of a semiconductor wafer (hereinafter simply referred to as“ wafer ”) W having a circuit pattern formed on the surface and the ring frame f. The mount frame MF is produced by affixing DT (abbreviated as “support tape”).

  As shown in FIG. 1 and FIG. 2, the wafer mount device is provided with a workpiece transfer device 1 that is long on the left and right sides in front of the device, and an adhesive tape DT that extends over the ring frame f and the wafer W on the back side in the center of the left and right. A pressure-sensitive adhesive tape pasting portion 2 for pasting and creating the mount frame MF is provided so as to protrude to the back side.

  A wafer supply unit 4 is provided on the front side of the apparatus, which is closer to the right side than the center of the left and right sides. A frame supply unit 6 is provided on the front side, which is closer to the left side than the center of the left and right sides. In addition, a holding table 7 for placing the wafer W and the ring frame f and feeding the wafer W and the ring frame f to the adhesive tape adhering unit 2 is arranged on the back side near the left and right center so as to be movable back and forth.

  The workpiece transfer device 1 includes a wafer transfer mechanism 9 that is supported on the right side of a guide rail 8 that is installed horizontally in the left and right direction so as to be reciprocally movable left and right, and a frame transfer mechanism 10 that is supported on the left side of the guide rail 8 so as to be movable left and right. And are provided. Further, an aligner 11 for positioning the wafer W using a notch or an orientation flat is installed on the right back side. Further, an aligner 12 for positioning the ring frame f is installed on the back side of the frame supply unit 6.

  The wafer transfer mechanism 9 is configured to transfer the wafer W taken out from the cassette 3 left and right and back and forth, and to reverse the posture of the wafer W. The detailed structure is shown in FIG. 3 and FIG.

  As shown in FIG. 3, a left / right movable movable base 14 that is movable back and forth along the guide rail 8 is provided. A longitudinally movable movable base 16 is provided so as to be movable back and forth along a guide rail 15 provided in the laterally movable movable base 14. Further, a wafer holding unit 17 is provided below the movable table 16 so as to be movable up and down.

  The wafer holding unit 17 includes an inverted L-shaped support frame 26 connected to the lower part of the longitudinally movable movable table 16, a lift 28 that is screwed up and down by a motor 27 along a vertical frame portion of the support frame 26, and a lift 28, a turntable 30 pivotally supported about a longitudinal support shaft p via a turning shaft 29, a turning motor 32 wound around the turning shaft 29 via a belt 31, and rotated. A wafer holding arm 34 is pivotally supported by a lower portion of the table 30 through a pivot shaft 33 so as to be pivotable about a horizontal support shaft q, and is coupled to the pivot shaft 33 via a belt 35 for reversal. The motor 36 is configured.

  As shown in FIG. 4, a U-shaped suction part 34 a having a vacuum suction hole 37 is provided on the front end side of the wafer holding arm 34. By using the above-described movable structure, the wafer W attracted and held by the wafer holding arm 34 is moved back and forth, moved left and right, and swiveled around the vertical fulcrum p and turned around the horizontal fulcrum q. Thus, the wafer W can be turned upside down.

  On the left side of the frame supply unit 6, as shown in FIG. 2, a storage unit 39 for loading and collecting the created mount frame MF is provided. The storage unit 39 includes a vertical rail 41 connected and fixed to the apparatus frame 40, and a lifting platform 43 that is screwed up and down by a motor 42 along the vertical rail 41. Accordingly, the mount frame MF is placed on the lifting / lowering platform 43 and is configured to move down the pitch.

  The frame transport mechanism 10 is configured to be able to take out the ring frames f stacked and mounted on the frame supply unit 6 in order from the uppermost stage and transport the ring frames f to the left and right and back and forth. The moving structure is the same as that of the wafer transfer mechanism 9.

  That is, as shown in FIG. 5, a left / right movable movable base 44 is provided that is movable back and forth along the guide rail 8 and is movable back and forth along a guide rail 45 provided on the left / right movable movable base 44. Is equipped with a movable table 46. Further, a frame holding unit 47 is mounted on the lower part of the longitudinally movable table 46 so as to be movable up and down.

  The frame holding unit 47 includes a vertical frame 56 coupled to a lower portion of the longitudinally movable movable table 46, a lifting frame 57 supported so as to be slidable along the vertical frame 56, and a bending / extending link mechanism 58 that moves the lifting frame 57 up and down. The motor 59 that drives forward and reverse bending and extension, and suction pads 60 that are provided at the front, rear, left, and right locations of the lower and lower frames 57, and the like. Therefore, the ring frame f loaded on the lifting / lowering platform 43 is lifted up by being sucked and held by the suction pad 60 in order from the uppermost one, and can be transported forward, backward, left and right. The suction pad 60 can be adjusted to slide in the horizontal direction corresponding to the size of the ring frame f.

  As shown in FIGS. 6A and 6B, the holding table 7 includes a circular wafer support 71 that holds the wafer W, and an annular frame support 72 that is disposed around the wafer support 71. And. The holding table 7 is configured to reciprocate along a guide rail (not shown) between a placement position indicated by a solid line in FIG. 1 and a tape application position indicated by a dotted line in FIG.

  A plurality of flow holes 73 are formed in a distributed manner on the upper surface of the wafer support base 71, and each flow hole 73 is connected to a flow path 74 formed inside the wafer support base 71. The flow path 74 has a function as a gas exhaust passage and a function as a gas supply passage, and communicates with the vacuum device 76 via an electromagnetic valve 75. The wafer W can be sucked and held on the upper surface of the wafer support 71 by the operation of the vacuum device 76. The vacuum device 76 corresponds to the suction mechanism in the present invention.

  The holding table 7 includes a gas supply device 77 and an electromagnetic valve 78, and the gas supply device 77 is communicated with the flow path 74 via the electromagnetic valve 78. The gas supplied by the gas supply device 77 is discharged from the flow hole 73 to the outside of the holding table 7 through the flow path 74. The electromagnetic valve 75 and the electromagnetic valve 78 adjust the pressure inside the flow path 74 by opening and closing. The operation of the vacuum device 76 and the gas supply device 77 and the opening and closing of the electromagnetic valve 75 and the electromagnetic valve 78 are controlled by the control unit 79, respectively. The gas supply device 77 corresponds to the gas supply means in the present invention.

  On the upper surface of the frame holding base 72, a shallow recessed step 80 that matches the outer shape of the ring frame f is formed. The ring frame f can be positioned and held concentrically with the central wafer W by fitting the ring frame f into the recessed step 80. Further, the upper surface of the ring frame f fitted in the recessed step 80 and the upper surface of the wafer W attracted and held by the wafer support 71 are configured to be flush with each other.

  As shown in FIGS. 7 and 8, the adhesive tape attaching unit 2 includes a tape supply unit 61, an attaching roller 62, a tape cutting mechanism 63, a peeling roller 64, a tape collecting unit 65, and the like.

  The tape supply unit 61 includes a supply bobbin 61 a for loading a wide support tape DT that has been rolled, and is configured to feed the support tape DT from the supply bobbin 61 a and guide it to the affixing roller 62. The supply bobbin 61a is provided with an appropriate rotational resistance so that excessive tape feeding is not performed.

  The affixing roller 62 presses the support tape DT fed out from the tape supply unit 61 to affix the support tape DT across the wafer W and the ring frame f. The tape cutting mechanism 63 cuts the support tape DT attached to the ring frame f and the wafer W into a circle larger than the inner diameter of the ring frame.

  As shown in FIGS. 7 and 14, the tape cutting mechanism 63 includes a boss portion 63 b that can move up and down and rotates around a support shaft 63 a. The boss portion 63b includes two support arms 63c. The support arm 63c extends in the radial direction around the boss portion 63b. A cutter bracket that horizontally supports a disc-shaped cutter 63d is attached to the tip of the support arm 63c.

  The peeling roller 64 peels unnecessary support tape Tn after being cut into a circle by the tape cutting mechanism 63 from the ring frame f. The tape collecting unit 65 winds and collects the unnecessary support tape Tn peeled off by the peeling roller 64.

  In the wafer mount apparatus according to the embodiment, the workpiece transfer apparatus 1 further includes a guide rail 66 and a restraining mechanism 67. As shown in FIG. 7, the guide rail 66 and the restraining mechanism 67 are disposed above the holding table 7 located at the placement position. The guide rail 66 is installed horizontally in the front-rear direction and guides the suppression mechanism 67 in the front-rear direction. The restraining mechanism 67 is not shown in FIG. 1 for the sake of clarity of the holding table 7.

  As shown in FIG. 9, the restraining mechanism 67 includes a movable table 68, a cylinder 69, and a restraining member 70, and restrains the wafer W when the wafer W is detached. The movable table 68 is configured to be movable back and forth along the guide rail 66. The cylinder 69 is disposed below the movable base 68 and is driven according to the control of the control unit 79.

  The restraining member 70 has a flat configuration having a flat surface 70 a wider than the wafer W, and is connected to the lower portion of the cylinder 69. The restraining member 70 is configured to be movable up and down in accordance with the driving of the cylinder 69. The position of the suppression member 70 in the z direction is controlled to an arbitrary position by the control unit 79. The inclination of the restraining member 70 is always controlled so that the flat surface 70a faces the surface of the wafer W. The control unit 79 corresponds to the proximity mechanism in the present invention.

  The restraining member 70 descends under the control of the control unit 79 and comes close to the upper surface of the wafer W held on the holding table 7. The material constituting the restraining member 70 preferably has a hardness that can restrain the wafer W that is about to be pushed up by the gas supplied by the gas supply device 77. Examples of the material include resin, rubber, sponge, A metal etc. are mentioned.

<Description of operation>
Next, an operation of creating the mount frame MF by attaching the support tape DT across the back surface of the wafer W and the ring frame f using the wafer mount apparatus according to the embodiment will be described. It is assumed that a protective adhesive tape PT (hereinafter abbreviated as “protective tape PT”) is attached to the circuit forming surface (front surface) of the wafer W. FIG. 10A is a flowchart showing the operation of the wafer mounting apparatus 1. In the initial state, the holding table 7 is at the mounting position indicated by the solid line in FIG.

Step S1 (wafer transfer)
When the mount frame MF creation command is issued, first, in the wafer transfer mechanism 9, the wafer W sucked and held by the wafer holding arm 34 is sent from the cassette 3 to the aligner 11 and aligned. The aligned wafer W is again sucked and held by the wafer holding arm 34, and then loaded into the holding table 7 with the surface to which the protective tape PT is attached facing downward, as shown in FIG. It is placed on the upper surface of the support base 71.

  The holding table 7 sucks and holds the mounted wafer W. The suction holding is performed by the vacuum device 76 exhausting the gas A in the flow path 74 formed inside the wafer support base 71. That is, when the control unit 79 opens the electromagnetic valve 75 and turns on the operation of the vacuum device 76, the gap between the lower surface of the wafer W and the holding table 7 is reduced by exhaust. Therefore, the wafer W is sucked and held on the holding table 7 via the protective tape PT.

Step S2 (ring frame transport)
On the other hand, in the frame transport mechanism 10, the ring frame f sucked and held by the suction pad 60 is sent from the frame supply unit 6 to the aligner 12 and aligned. The aligned ring frame f is again sucked and held by the suction pad 60, then carried into the holding table 7, and fitted into the recessed step 80 of the frame holding base 72 as shown in FIG. The ring frame f is placed concentrically with the wafer W by being fitted into the recessed step 80. Note that the order of step S1 and step S2 may be reversed or may be performed simultaneously.

Step S3 (Attaching the support tape)
After the transfer of the wafer W and the ring frame f is completed, the application of the support tape is started. As shown in FIG. 12, in the initial state, the affixing roller 62 and the peeling roller 64 are on the right side of the support table 7 that has moved to the tape affixing position, and the tape cutting mechanism 63 has moved to the tape affixing position. Above the support table 7.

  Here, the holding table 7 on which the wafer W and the ring frame f are placed is carried to the tape application position indicated by the dotted line in FIG. When the holding table 7 is carried into the tape application position, as shown in FIG. 13, the application roller 62 travels from the initial position indicated by the dotted line toward the end position indicated by the solid line, while moving the wafer W and the ring frame f. A support tape DT is applied over the upper surface of the substrate. The mount frame MF is created by attaching the support tape DT.

Step S4 (cutting of support tape)
After the attachment of the support tape DT is completed, the cutting of the support tape is started. That is, as shown in FIG. 14, the tape cutting mechanism 63 is lowered from the initial position indicated by the dotted line to the cutting position indicated by the solid line. The tape cutting mechanism 63 that has moved to the cutting position pivots around an axis P that is concentric with the center of the wafer, and the cutter 63d moves the support tape DT attached to the ring frame f and the wafer W in accordance with the pivoting. Cut on the ring frame f. By this cutting, the belt-like support tape DT is cut into a circle larger than the inner diameter of the ring frame.

Step S5 (Peeling of support tape)
When the cutting of the support tape DT is completed, peeling of the support tape is started. That is, as shown in FIG. 15, the peeling roller 63 peels unnecessary support tape Tn remaining outside the cutting line from the ring frame f while traveling from the initial position indicated by the dotted line toward the terminal position indicated by the solid line. . Due to the peeling of the support tape Tn, the reverse mounting frame MF is left on the holding table 7.

  With the mounting frame MF facing backward, the holding table 7 is moved from the tape application position inside the adhesive tape application unit 2 to the placement position inside the work transfer device 1 and on the front side of the wafer mount device. Carried out. Meanwhile, the sticking roller 62 and the peeling roller 63 move to their original initial positions. At the same time, the support tape DT fed out from the tape supply unit 61 is supplied above the attaching position, and unnecessary support tape Tn is wound up and collected by the tape collection unit 65.

Step S6 (wafer removal)
After peeling off the support tape, the wafer is detached from the holding table 7 that has moved to the mounting position. That is, the holding force of the holding table 7 with respect to the wafer W is reduced by supplying gas between the wafer support 71 and the wafer W in a state where the suppression mechanism 67 is brought close to the wafer W on the holding table 7. After that, the suction pad 60 of the frame holding unit 47 sucks the ring frame f to detach the mount frame MF from the holding table 7. Details regarding the wafer removal process will be described later.

Step S7 (collection of mount frame)
The suction pad 60 stores the mount frame MF detached from the holding table 7 in the original position of the frame supply unit 6. The wafer mount apparatus 1 may further include a mount frame storage unit (not shown), and the mount frame MF may be stored in the mount frame storage unit. Thus, a round of operations for creating the mount frame MF is completed, and thereafter the same processing is repeated.

<Details of wafer removal process>
Here, the wafer detachment process according to step S6, which is characteristic in the present invention, will be described in detail. The wafer detachment process according to step S6 is performed according to the processes from step S6-1 to step S6-5 shown in the flowchart of FIG. In the initial state, the suppression mechanism 67 is positioned above the holding table 7 that has moved to the mounting position.

Step 6-1 (Stop of gas discharge)
In the wafer detachment process, gas discharge is first stopped. That is, the control unit 79 closes the electromagnetic valve 75 and controls the vacuum device 76 to an off state. The control of the control unit 79 stops the discharge of the gas in the flow path 74 by vacuum suction.

Step 6-2 (proximity member movement)
After the stop of the gas discharge is completed, the restraining member is moved closer. That is, as shown in FIG. 16, the control unit 79 controls the cylinder 69 and the like to lower the restraining member 70 from the initial position indicated by the dotted line to the restraining position indicated by the solid line. Under the control of the control unit 79, the suppression member 70 is brought close to the wafer W placed on the holding table 7. In addition, you may perform the process of step S6-2 before step S6-1.

  In this embodiment, the restraining member 70 is moved to the restraining position, and the height of the restraining position is determined in advance so that the flat surface 70a contacts the support tape DT attached to the wafer W. That is, the flat surface 70a contacts the wafer W via the support tape DT at the restraining position. Further, the control unit 79 continues to control the position of the suppression member 70 so as to maintain the state in which the suppression member 70 is in contact with the support tape DT until a step S6-3 described later is completed. That is, the control member 79 fixes the suppression member 70 at the suppression position, and the distance between the suppression member 70 and the wafer W is maintained at zero. The process according to step S6-2 corresponds to the proximity process in the present invention.

Step 6-3 (Gas supply)
After the restraining member 70 is moved close to the wafer W, the supply of gas is started. That is, as shown in FIG. 17, the control unit 79 controls the gas supply device 77 to be on and opens the electromagnetic valve 78. The gas supply device 77 supplies the gas A into the flow path 74 under the control of the control unit 79. The gas A supplied to the flow path 74 is discharged from the flow hole 73.

  The gas discharged from the circulation hole 73 drives a part of the protective tape PT that has entered the hole of the circulation hole 73 to the surface of the wafer support 71 when the holding table 7 holds the wafer W by suction. In addition, since the gas ejected from the circulation hole 73 is supplied between the protective tape PT attached to the wafer W and the wafer support base 71, the decompressed state between the protective tape PT and the wafer support base 71 is reduced. It is released reliably. By releasing the reduced pressure state, the holding force of the holding table 7 on the entire wafer W is uniformly reduced.

  In step S <b> 6-3, an upward pressing force acts on the wafer W by the gas discharged from the circulation hole 73. However, the entire surface of the wafer W is in contact with the flat surface 70 a of the suppression member 70 via the support tape DT, and the position of the suppression member 70 is maintained at the suppression position by the control unit 79.

  Therefore, the upward movement of the wafer W due to the pressing force of the gas A is reliably restrained by the restraining member 70. Therefore, the deformation and breakage of the wafer W due to the pressing force acting non-uniformly on the wafer W can be reliably avoided. The gas is supplied from the gas supply device 77 to release the reduced pressure state between the wafer support 71 and the protective tape PT, whereby the process of step S6-3 is completed. The process according to step S6-3 corresponds to the gas supply process in the present invention.

Step 6-4 (Separation movement of restraining member)
After the gas supply and the release of the reduced pressure state are completed, the separation member starts to move away. In step S6-4, first, the supply of gas to the flow path 74 is stopped. That is, the control unit 79 closes the electromagnetic valve 78 and controls the gas supply device 77 to an off state.

  After stopping the gas supply, the restraining member is separated from the wafer W. That is, as shown in FIG. 18, the control unit 79 controls the cylinder 69 and the like to move the restraining member 70 upward from the restraining position to the initial position. Since the separation movement of the restraining member 70 is performed after the gas supply is stopped, it is possible to avoid a situation in which the wafer W is deformed or damaged in the process after the restraining member 70 is separated from the wafer W.

Step 6-5 (wafer separation movement)
After the restraining member 70 is separated from the wafer W, the wafer is moved away. That is, as shown in FIG. 19, the suction pad 60 provided in the frame transport mechanism 10 is close to the ring frame f and sucks and holds the upper surface of the ring frame f. The suction pad 60 moves upward in accordance with the control of the control unit 79 while maintaining the suction holding.

  As the suction pad 60 moves upward away from the holding table 7, the mount frame MF is detached from the holding table 7. That is, the wafer W is detached from the holding table 7 together with the ring frame f and the support tape DT.

  By completing the process of step S6-5, all the series of processes related to step S6 are completed. Thereafter, the process proceeds to step S7, and the suction pad 60 stores the mount frame MF in a predetermined position with the ring frame f being sucked and held.

<Effects of Configuration of Example>
When various processes such as a dicing process or an adhesive tape pasting process are performed on the wafer, the process is performed by placing the wafer on a flat holding table. At this time, in order to prevent displacement of the mounted wafer, a vacuum device is generally provided on the holding table to hold the wafer by suction.

  That is, as shown in FIG. 20A, the wafer is sucked and held on the holding table Tb by discharging the gas A from the flow path Tk inside the holding table Tb by the vacuum device. Then, after the processing is completed, the suction holding is released by stopping the discharge of the gas A, and the wafer W is detached from the holding table Tb upward.

  In such a conventional configuration, only the operation of stopping the discharge of the gas A is performed. Therefore, as shown in FIG. 20B, a situation occurs in which the reduced pressure state is not sufficiently released at a part G of the boundary between the lower surface of the wafer W and the holding surface of the holding table Tb. In this case, in the region G, the holding force of the holding table Tb on the wafer W is not sufficiently reduced.

  For this reason, as shown in FIG. 20C, when the wafer W is lifted and removed, a part of the wafer W in contact with the holding table Tb in the region G causes a separation delay. In this case, when the wafer W is detached, a particularly strong shearing force is generated around the region G, so there is a concern that the wafer W may be deformed or broken.

  In order to solve the problem of the separation delay due to the remaining decompressed state, the configuration according to Patent Document 1 not only stops the discharge of the gas A but also supplies the gas. That is, as shown in FIG. 21 (a), the gas flows between the lower surface of the wafer W (the lower surface of the adhesive tape T1 attached to the wafer W in the drawing) and the holding table Tb via the flow path Tk. Supply A. As shown in FIG. 21B, the depressurized state in the region G is released by the supplied gas A, so that the wafer W can be prevented from being delayed by releasing the wafer W after supplying the gas.

  However, as a result of examination by the inventors, the configuration of Patent Document 1 in which the wafer W is detached after supplying the gas A has led to the finding that it is difficult to reliably avoid the problems of wafer deformation and breakage. It was. That is, since the supplied gas A is jetted upward from the hole of the flow path Tk, the wafer W is pushed up particularly strongly in the region where the flow path Tk is provided. For this reason, as shown in FIG. 21C, an upward pressing force Pa acts on the wafer W non-uniformly, so that there is a concern that at least a part of the wafer W protrudes upward and the wafer W is deformed. .

  In particular, when dicing, half dicing, stealth dicing, or the like is performed on the wafer W to reduce the strength of the wafer W, a problem that a part of the wafer is broken or dissipated more significantly occurs. FIG. 21E shows a wafer W that has undergone a half dicing process as an example. That is, since the pressing force Pa acts non-uniformly on the wafer W, a relatively strong pressing force Pa acts upward on the wafer W around the area where the flow path Tk is disposed, while the flow path In a region far from the region where Tk is disposed, the pressing force Pa is relatively weak.

  Therefore, as shown in FIG. 21 (e), since a shearing force is generated due to the difference in the pressing force Pa, a part Wa of the wafer W partitioned by half dicing is torn and dissociated from the other part Wb. The wafer W is damaged. Further, when the adhesive tape T2 is not attached to the upper surface of the wafer W, a situation occurs in which a part Wa of the torn wafer W is pushed upward and scattered. Thus, in the conventional wafer detachment process in which gas is supplied, it has been found that a new problem occurs due to the shearing force of the supplied gas.

  Therefore, in the substrate detachment process according to the embodiment, as shown in FIG. 22A, the protective tape PT attached to the wafer W is held with the flat surface 70a of the restraining member 70 in contact with the wafer W. Gas is supplied between the table 7. That is, while the wafer W is restrained by the close restraining member 70, gas is supplied to reduce the holding force of the holding table 7, and then the wafer W is detached from the holding table 7.

  In the configuration of such an embodiment, since the wafer W is detached from the holding table 7 after the gas A is supplied and the decompression region G is eliminated, the deformation and breakage of the wafer due to the separation delay can be prevented. As shown in FIG. 22B, even if the wafer W is pushed up by the pressing force Pa of the supplied gas A, the wafer W is quickly restrained by the restraining member 70 in contact with the wafer W. That is, the restraining member 70 is controlled so as to maintain a position close to the wafer W (a restraining position).

  For this reason, the wafer W about to move upward by the pressing force Pa is quickly received by the flat surface 70a at the restraining position and does not move upward from the restraining position, so that at least a part of the wafer W protrudes upward. Can avoid the situation. Therefore, problems such as deformation, breakage, and dissipation of the wafer W, which are generated when a part of the wafer protrudes due to gas supply, can be reliably solved.

  In addition, the restraining member 70 that has moved from the initial position to the restraining position does not press the wafer W, but maintains a state of contacting the wafer W. For this reason, when the pressing force Pa is not applied to the wafer W, a situation in which the wafer W is unnecessarily pressed downward by the restraining member 70 does not occur, so that deformation and breakage of the wafer W can be reliably avoided.

  On the other hand, when the pressing force Pa is acting on the wafer W, the restraining member 70 is controlled to maintain the restraining position, so that the situation in which the restraining member 70 is pushed up from the restraining position by the pressing force Pa can be avoided. Accordingly, the restraining member 70 can reliably and promptly restrain at least a part of the wafer W from moving away from the holding table 7 by maintaining the restraining position.

  Further, the flat surface 70 a of the restraining member 70 is configured to be wider than the entire surface of the wafer W and to face the surface of the wafer W. For this reason, since the flat surface 70a uniformly abuts against the entire surface of the wafer W, when the wafer W is restrained by the restraining member 70, it is ensured that the repulsive force acts unevenly on the surface of the wafer W. Can be avoided. Therefore, it is possible to prevent the wafer W from being deformed or damaged when the wafer W is restrained.

  With such a configuration, the holding force of the holding table 7 with respect to the entire wafer can be suitably reduced while avoiding deformation and breakage of the wafer W due to gas supply in the wafer detachment process according to the embodiment. Accordingly, the problem that the wafer W is delayed and deformed / damaged due to the remaining decompressed region, and the supplied gas A is ejected from the flow hole 73 and shears the wafer W to deform / transform the wafer. Both the problem of breakage can be solved reliably.

  The present invention is not limited to the above embodiment, and can be modified as follows.

  (1) In the embodiment, the restraining position of the restraining member 70 is set so that the restraining member 70 comes into contact with the wafer W, but is not limited thereto. That is, as shown in FIG. 23A, in step S6-2, by moving the restraining member 70 to the restraining position (closer to the wafer W), the flat surface 70a and the wafer W are set to a predetermined minute distance D1. You may comprise so that it may adjoin and oppose.

  In other words, the proximity process in the present invention refers to “a configuration in which the restraining member 70 is brought close enough to abut against the wafer W” as in the embodiment, and “the restraining member 70 is located at a minute distance from the wafer, as in the present modification. And a configuration in which the distance between the two is close enough to face each other. Note that the length of the minute distance D1 varies depending on various conditions such as the thickness of the wafer W and the material of the protective tape PT. In the modification example (1), the minute distance D1 is preferably 1 mm or less as an example, and more preferably 0.5 mm or less.

  In the configuration of the modification (1) as described above, a position away from the wafer W by a minute distance D1 is set in advance as a suppression position. In step S6-2, the control unit 79 moves the restraining member 70 to the restraining position to bring it close to the wafer W, and maintains the restraining member 70 in the restraining position until the step S6-3 is completed.

  Therefore, when supplying the gas A to the flow path 74 in step S6-3, even if the pressing force Pa acts on the wafer W by the gas A, the wafer W is a flat surface at a position separated by a minute distance D1. It is suppressed by 70a. In other words, since the distance that the wafer W moves by the pressing force Pa can be suppressed to the minute distance D1 or less, the deformation or breakage of the wafer W that occurs when a part of the wafer W moves largely upward is more reliably performed. Can be prevented.

  Further, in the configuration of the modified example (1), in step S6-3, there is a spatial margin that allows the wafer W to move upward by a minute distance D1. By moving the wafer W by a small distance upward by the pressing force Pa, a gap of a maximum distance D1 is formed between the protective tape PT attached to the wafer W and the holding table 7. That is, since the gas A supplied to the flow path 74 can suitably enter the formed gap, the reduced pressure region G that can remain after the vacuum suction is stopped can be more reliably eliminated.

  (2) In the embodiment and each modified example, the case where the wafer W is detached from the holding table 7 in the wafer mounting process has been described as an example. The present invention can be appropriately applied to a configuration in which the wafer is detached from the holding table that is sucked and held.

  That is, the configuration of the substrate detaching apparatus using the restraining member according to the present invention can be applied regardless of the contents of the processing performed on the wafer held on the holding table. Examples of applicable processes include an adhesive tape sticking process, a back grinding process, a dicing process, and an adhesive tape transfer process on the wafer W.

  Here, as an example, an example applied to a mounting frame transfer process will be described. That is, as shown in FIG. 24A, a mount frame MF1 formed by attaching a support tape DT1 to one surface of the wafer W and the ring frame f1 is sucked and held on the holding table 7 and supported by the cutter blade C. The tape DT1 is cut along the outer shape of the wafer W. Then, after unloading the ring frame f1, a new ring frame f2 is loaded, and the support tape DT2 is attached across the other surface of the wafer W and the ring frame f2, thereby transferring to the new mount frame MF2 (FIG. 24 (b)).

  After the transfer process is completed, the mount frame MF2 is detached from the holding table 7 while preventing the wafer W from being damaged by executing a wafer removal process according to the present invention. That is, as shown in FIG. 24C, the gas A is supplied between the mount frame MF <b> 2 and the holding table 7 through the flow path 74 in a state where the suppressing member 70 is in contact with or close to the wafer W. After reducing the holding force of the holding table 7 by supplying the gas A and releasing the reduced pressure state, the mount frame MF2 is moved away from the holding table 7.

  (3) In the embodiment and each modified example, the configuration in which the wafer W in a state where the adhesive tape is stuck on both surfaces is detached from the holding table 7 has been described as an example, but the present invention is not limited thereto. That is, even if one or both of the front and back surfaces of the wafer W are exposed, the substrate removing apparatus and the substrate removing method according to the present invention can be applied. As shown in FIG. 25, when the restraining member 70 is brought into direct contact with the wafer W whose upper surface is exposed, the restraining member 70 is made of, for example, an elastic body or sponge. More preferably, the material can avoid damage to the wafer due to contact between the wafer and the upper surface of the wafer.

  (4) In the embodiment and each modification, the restraining member 70 may be configured to hold the wafer W. As an example, the restraining member 70 is connected to a second vacuum device (not shown), and the restraining member 70 can be sucked by vacuum suction by the operation of the second vacuum device. In the wafer detaching process according to the modified example (4), after the completion of step S6-3, as shown in FIG. Then, the wafer W is stored in a predetermined storage unit.

  That is, in Modification (4), the restraining member 70 has the functions of restraining the wafer W, detaching the wafer W (lifting the wafer), and transporting the wafer W. Therefore, in the modified example (4), the process of step S6-4, step S6-5, and step S7 can be continuously executed by the restraining member 70, so that the processing time can be shortened and the apparatus configuration can be simplified more suitably. it can. In addition, it is not restricted to the structure which newly provides a 2nd vacuum apparatus independently of the vacuum apparatus 76, the vacuum apparatus 76 and the suppression member 70 are connected, and the vacuum apparatus 76 is the adsorption holding and suppression member 70 by the holding table 7. It may be configured to execute each of the adsorption holding by the above.

  Further, if the configuration according to the modification (4) is a configuration in which the suppression member 70 is detached from the holding table 7 while holding the wafer W, the configuration in which the suppression member 70 holds the wafer W is limited to holding by suction. Absent. As another example of the configuration according to the modification (4), there is a configuration in which the suppression member 70 holds the wafer W by a mechanical clamping operation, such as a configuration in which a grip arm provided on the suppression member 70 grips the wafer W. Can be mentioned. In the modification (4), the second vacuum device or the gripping arm corresponds to the holding mechanism in the present invention.

  (5) In the embodiments and modifications, each of the wafer support 71 and the restraining member 70 may further include a heater. In this case, when performing the process of sticking the adhesive tape to the wafer W, the adhesive and the base material constituting the adhesive tape are heated and softened by the heater. As a result, it becomes easier to deform the adhesive tape. Note that either the wafer support base 71 or the restraining member 70 may include a heater.

  (6) In the example and each modification, the size of the flat surface 70a may be changed as appropriate. That is, the size is not limited to a size wider than the entire surface of the wafer W, and may be a size corresponding to the circuit formation region of the wafer or a size corresponding to a region where the flow holes 73 are formed in the wafer support 71.

  (7) In the embodiment and each modified example, if the gas A can be supplied between the holding table 7 and the wafer W, the gas A is supplied via the flow path 74 built in the holding table 7. Not limited. As an example, gas A is supplied between the holding table 7 and the wafer W through a pipeline that is provided outside the holding table 7 and has a supply port inserted between the holding table 7 and the lower surface of the wafer W. It may be configured to.

  (8) In the embodiments and the modifications, the wafer support 71 of the holding table 7 may be made of a porous material such as aluminum oxide.

  (9) Although the detaching apparatus according to the embodiment and each modification has been described as an example of a configuration for detaching the wafer W from the holding table 7, the target to be detached from the holding table 7 is not limited to the wafer. That is, the configuration of the detaching apparatus according to the present invention can be applied to the case of detaching a general board such as a printed board.

  (10) In the embodiment and each modification, at least one of the operation of placing the wafer W on the holding table 7 and the operation of removing the wafer W from the holding table 7 may be performed manually by an operator. As an example, when the configuration in which the operation of manually removing the wafer W from the holding table 7 is applied to the embodiment, the operator holds the wafer W in a state where the holding force of the holding table 7 with respect to the wafer W is reduced by the supply of gas. It is lifted from the holding table 7 together with the ring frame f. In addition, the structure performed manually also about the operation | movement which mounts the ring frame f is applicable.

DESCRIPTION OF SYMBOLS 7 ... Holding table 10 ... Frame conveyance mechanism 60 ... Adsorption pad 62 ... Sticking roller 70 ... Inhibiting member 70a ... Flat surface 71 ... Wafer support stand 72 ... Frame support part 73 ... Flow hole 74 ... Flow path 76 ... Vacuum device 77 ... Gas Supply device 79 ... control unit W ... wafer PT ... protective tape DT ... support tape f ... ring frame MF ... mount frame

Claims (8)

A substrate removal method for removing the substrate from a holding table that holds the substrate by suction,
Proximity process that has a flat surface and suppresses the substrate close to or abuts the substrate, and maintains the distance between the substrate and the flat surface at a predetermined value,
A gas supply process for supplying a gas so as to reduce the holding force of the holding table between the substrate and the holding table in a state where the suppression member is close to or in contact with the substrate;
A detaching process for detaching the substrate from the holding table;
A method for removing a substrate, comprising: The method for detaching a substrate according to claim 1,
The substrate detachment method, wherein the detachment process is executed by detaching the restraining member from the holding table together with the substrate in a state where the restraining member holds the substrate. In the removal method of the board | substrate of Claim 1 or Claim 2,
The method for removing a substrate, wherein the predetermined value is 0.5 mm or less. A holding table for placing and holding the substrate;
A suction mechanism provided on the holding table and holding the substrate by suction on the holding table;
A deterring member having a flat surface and deterring the substrate;
A proximity mechanism for controlling the restraining member to approach or abut the substrate and maintain a distance between the flat surface and the substrate at a predetermined value;
A gas supply means for supplying a gas so as to reduce a holding force of the holding table between the holding table and the substrate in a state where the suppression member is in proximity to or in contact with the substrate;
An apparatus for detaching a substrate, comprising: The substrate removal apparatus according to claim 4, wherein
A holding mechanism that is provided on the suppression member and holds the substrate on the suppression member;
A substrate detachment apparatus, wherein the restraining member holds the substrate and detaches the substrate from the holding table by detaching from the holding table having a reduced holding force. In the board | substrate detachment apparatus of Claim 4 or Claim 5,
The flat surface is wider than the substrate,
The proximity mechanism causes the restraining member to approach or abut so that the flat surface faces the substrate. In the removal apparatus of the board | substrate in any one of Claim 4 thru | or 6,
The holding table has a frame holding unit for holding a ring frame;
An apparatus for detaching a substrate, comprising: an attachment mechanism for attaching an adhesive tape to the ring frame and the substrate held on the holding table to create a mount frame. In the removal apparatus of the board | substrate in any one of Claim 4 thru | or 7,
The method for removing a substrate, wherein the predetermined value is 0.5 mm or less.

Images