TW202407870A - How to deal with frame units - Google Patents

Abstract

The invention provides a processing method of a frame unit, which can press down a frame of the frame unit supported by a frame supporting part so as to enable a wafer to protrude upwards regardless of the type of the wafer. In the processing method of the frame unit, the frame unit is obtained by positioning a wafer in an opening part of a frame having the opening part for accommodating the wafer in the center and integrating the wafer and the frame through a sheet. The frame unit processing method includes a groove forming step of forming a groove in a sheet located between a wafer and a frame.

Description

How to deal with frame units

The present invention relates to a processing method of a frame unit. The frame unit is formed by positioning a wafer in an opening of a frame and integrating it with the frame through a sheet. The frame has the opening for accommodating the wafer in the center.

A wafer with a plurality of components such as ICs and LSIs divided by planned dividing lines is formed on the front side and is divided into individual component wafers by a cutting device and a laser processing device, and is used in mobile phones, personal computers, etc. electronic equipment.

Even if the wafer is divided into individual component wafers by a dicing device or the like, the wafer is transported to the next step while maintaining the shape of the wafer. The wafer is positioned at the opening of the frame and The frame unit is carried into the dicing device in a state of being integrated with a frame having the opening for accommodating the wafer in the center (see, for example, Patent Documents 1 and 2).

Furthermore, the above-mentioned frame unit is transported to holding means including a wafer stage that supports the wafer and a frame support portion that is disposed on the outer periphery of the wafer stage and supports the frame, and the wafer is attracted and held by the wafer stage. , the frame is pressed down when supported by the frame support part, so that the position of the frame is lower than the wafer and the wafer protrudes above. [Known technical documents] [Patent Document]

[Patent Document 1] Japanese Patent Application Publication No. 2007-201178 [Patent Document 2] Japanese Patent Application Publication No. 2010-036275

[Problem to be solved by the invention] However, as the sheet that integrates the wafer and the frame described in the above-mentioned Patent Documents 1 and 2, various types such as vinyl chloride sheet, polyethylene sheet, polypropylene sheet, and polystyrene sheet are used. Due to various reasons, The sheet has different elongation rates, and depending on the type of sheet selected, there is a problem that the sheet does not extend appropriately when supported by the frame support, and thus cannot properly press down the frame.

The present invention was completed in view of the above-mentioned facts, and its main technical subject is to provide a frame unit processing method that can project the frame of the frame unit supported by the frame support part with the wafer upward regardless of the type of the sheet. way to press down.

[Technical means to solve the problem] In order to solve the above-mentioned main technical problems, according to the present invention, there is provided a processing method of a frame unit in which a wafer is positioned at an opening of the frame and integrated with the frame through a thin sheet. The opening for accommodating the wafer is provided in the center, and the processing method of the frame unit includes a groove forming step of forming a groove in the sheet between the wafer and the frame.

It is also possible to perform a wafer protruding step after the groove forming step. In the wafer protruding step, the frame unit is placed on the holding means, the frame is supported by the frame support portion, and the wafer is protruded from the frame. The holding means includes a wafer stage that supports the wafer and a frame support portion that is disposed on the outer periphery of the wafer stage and supports the frame. In addition, after the wafer protruding step, a processing step may be performed on the protruded wafer. Furthermore, after the wafer protruding step, a transfer step may also be performed. The transfer step is to arrange other sheets on the protruded wafer and transfer the wafer to other sheets.

[Invention effect] The processing method of a frame unit of the present invention is a processing method of a frame unit in which a wafer is positioned at an opening of a frame and is integrated with the frame through a sheet, and the frame has the opening in the center for accommodating the wafer. The processing method of the frame unit includes a groove forming step. The groove forming step is to form a groove in a sheet between the wafer and the frame. Therefore, the tensile stress is relaxed by the groove formed in the sheet, and becomes even Even when a sheet with low elongation is used, the wafer can protrude well from the frame.

Hereinafter, embodiments of the processing method of the frame unit configured according to the present invention will be described in detail with reference to the accompanying drawings.

The upper part of FIG. 1 shows a state in which the frame unit U processed by the frame unit processing method of this embodiment is formed. When forming the frame unit U, first, the wafer 10, the frame F, and the sheet T as shown in the figure are prepared. The wafer 10 is made of silicon, for example, and is a circular plate-shaped wafer in which a plurality of elements 12 divided by planned dividing lines 14 are formed on the front surface 10 a. The frame F is a ring-shaped plate made of, for example, stainless steel and has an opening Fa for accommodating the wafer 10 in the center. The sheet T is, for example, a resin sheet having an adhesive layer on its surface, and its outer periphery is adhered to the back of the frame F. In addition, the sheet T is not limited to a resin sheet having an adhesive layer. For example, it may be a thermocompression-bonded sheet that is softened by being heated to exert adhesive force. When forming the frame unit U, as shown in the figure, the wafer 10 is positioned at the opening Fa of the frame F, and the front surface of the sheet T whose outer periphery is bonded to the frame F is bonded to the back surface 10 b of the wafer 10 . As a result, as shown in the lower part of FIG. 1 , a frame unit U is formed in which the wafer 10 and the frame F are integrated with the sheet T.

Once the frame unit U has been prepared as described above, the frame unit U is transported to the laser processing device 20 as shown in FIG. 2 (only part of it is shown) in order to perform the groove forming step on the frame unit U. The area of the sheet Ta between the wafer 10 and the frame F among the sheets T forms a groove. The frame unit U that has been transported to the laser processing apparatus 20 is placed on a holding means (not shown). This holding means uses the flat surface of the entire support frame unit U as a holding surface, and an adsorption means having a plurality of suction holes is arranged on the holding surface. The holding means includes: an X-axis feeding means, which performs processing and feeding in the The light irradiation means 22 relatively performs processing feed in the Y-axis direction orthogonal to the X-axis; and the rotation drive means rotates the holding means (both are omitted from the illustration).

After the frame unit U that has been transported to the laser processing apparatus 20 is placed on the holding means, it is attracted and held on the holding surface of the holding means by the operation of the attraction means (not shown). The frame unit U attracted and held by the holding means is photographed using an imaging means (not shown) provided in the laser processing device 20, and alignment is performed. By this alignment, the area and shape of the sheet Ta located between the wafer 10 and the opening Fa of the frame F in the frame unit U are detected.

If the shape of the sheet Ta located between the wafer 10 and the opening Fa of the frame F is detected through the above-mentioned alignment, the above-mentioned X-axis feeding means and Y-axis feeding means are operated, and the laser light is The irradiation means 22 is positioned above a predetermined processing start position in the area of the sheet Ta. Next, the focusing point of the laser light LB having an absorptive wavelength for the sheet Ta is positioned on the front surface of the sheet Ta and irradiated, and the frame unit U is processed and fed in the X-axis direction along the predetermined processing schedule. The area of the sheet Ta is subjected to ablation processing to form a predetermined groove 100 as shown in the figure. This groove 100 is a groove that does not penetrate to the back side of the sheet Ta, and is formed to a depth that will not break the sheet Ta even if the sheet Ta is expanded by performing a wafer bumping step described later.

If the above-mentioned groove 100 has been formed on the predetermined planned processing line, the frame unit U is indexed and fed in the Y-axis direction only at predetermined intervals determined in advance by the Y-axis feeding means, and along the Y-axis feeding means Predetermined processing lines adjacent in the axial direction are irradiated to the sheet Ta with the laser beam LB in the same manner as described above, and the frame unit U is processed and fed in the X-axis direction to form the groove 100 . In the same manner, the frame unit U is processed and fed in the X-axis direction and indexed in the Y-axis direction to form a plurality of grooves 100 in the area of the sheet a. If a plurality of grooves 100 are formed in parallel over the entire area of the sheet Ta, the frame unit U is rotated 90 degrees so that the direction orthogonal to the direction in which the grooves 100 are formed is aligned with the X-axis direction. Then, in the same manner as above, the focusing point of the laser light LB is positioned at the area of the sheet Ta and irradiated, and a plurality of laser beams are formed at the predetermined intervals in the direction orthogonal to the previously formed grooves 100. slot 100. Through the above operations, the groove forming step of this embodiment is completed. By this groove forming step, as shown in FIG. 2( b ), a plurality of grooves 100 are formed in a grid pattern in the area of the sheet Ta of the frame unit U. In this way, by forming the grooves 100 in the sheet Ta in a grid pattern, even if the sheet Ta is made of a material with a low elongation rate, the tensile force when expanding the area of the sheet Ta can be relaxed, so that the area of the sheet Ta can be expanded. The sheet Ta is appropriately stretched.

In addition, in the groove forming step in the above embodiment, although the plurality of grooves 100 are formed in a grid shape, the shape of the grooves formed by the groove forming step of the present invention is not limited thereto. For example, as shown in FIG. 3( a ), multiple annular grooves 110 may be formed in the entire area of the sheet Ta located between the wafer 10 and the frame F. In the case of forming the groove 110, the above-mentioned laser light irradiation means 22 is positioned within the area of the sheet Ta, that is, at a predetermined radial position from the center position of the frame unit U, and the light condensing point position is positioned at the center of the sheet Ta. The front side is irradiated with laser light LB, and the frame unit U is rotated in the direction shown by arrow R1 to form an annular groove 110 . Once the groove 110 has been formed, a plurality of the grooves 110 can be formed by changing the distance from the center position of the frame unit U to the position where the laser light LB is irradiated at predetermined intervals. Multiple annular grooves 110 as shown in Figure 3(a).

Furthermore, the shape of the groove formed by the groove forming step of the present invention may also be the shape shown in FIG. 3(b) . In the form shown in FIG. 3( b ), in the area of the sheet Ta, a plurality of grooves 120 are formed in a radial direction with the center of the frame unit U as the base end. When forming the groove 120, the laser beam irradiation means 22, X-axis feeding means, Y-axis feeding means, etc. of the above-mentioned laser processing device 20 can also be operated, and the detailed description is omitted. In addition, the shape of the groove formed by the groove forming step of the present invention is not limited to the above-mentioned shape, and may also be a combination of the above-mentioned grooves 100 to 120 .

In the above-mentioned groove forming step, as for the holding means of the laser processing device 20 , although it has been described that the side of the frame unit U to which the wafer 10 is pasted faces upward and the side of the sheet T faces downward, and is positioned on the wafer 10 The above-mentioned grooves 100 to 120 are formed between the sheet Ta and the frame F. However, the present invention is not limited thereto. The sheet T can also be held with the T side facing upward and the side to which the wafer 10 is pasted facing downward. In the above-mentioned sheet T, the area of the sheet Ta forms a groove.

Furthermore, in the above-described embodiment, the laser beam irradiation means 22 of the laser processing device 20 is used to form the grooves 100 to 120. However, the present invention is not limited thereto, and a cutting processing device (not shown) may also be used. , and the groove is formed by a cutting blade with an annular cutting edge. When the cutting blade is used to form a groove in the area of the sheet Ta of the above-mentioned frame unit U, it is preferable to turn the frame unit U up and down as shown in the lower section of FIG. 1 and hold the sheet T side upward in the cutting device. The holding means can also be formed by the dicing blade of the dicing device, and the groove formed by the dicing blade in the area of the sheet Ta between the wafer 10 and the frame F is formed, for example, by the above-mentioned groove 100~ The shape formed by 120.

If a groove has been formed in the sheet Ta between the wafer 10 and the frame F in the frame unit U through the above-mentioned groove forming step, the wafer protruding step described below can be performed.

The wafer protruding step in this embodiment is a step performed to perform cutting processing on the wafer 10 by the cutting device 30 shown in FIG. 4 . The cutting device 30 is provided with a substantially rectangular parallelepiped-shaped housing 31, and is provided with a cassette 32 placed on the cassette stage 32a of the housing 31, and an unloading and unloading means 34 for unloading the frame unit U from the cassette 32 to a temporary placement stage. 33; The transport means 35 has a swing arm that transports the frame unit U carried out to the temporary placement table 33 to the holding means 36 provided with the wafer table 36a; the cutting means 38 is rotatably provided The dicing blade 38a performs cutting processing on the wafer 10 held on the wafer table 36a; the alignment means 37 is used for photographing the wafer 10 held on the wafer table 36a, and detects the area to be cut by the cutting means 38; and the cleaning and unloading means 39a, which transfers the frame unit U including the wafer 10 from the unloading and unloading position where the wafer table 36a is positioned in FIG. 4 to the cleaning device 39 (details are omitted ). The wafer stage 36 a has a holding surface for holding the wafer 10 on its upper surface, and the size of the holding surface corresponds to the diameter of the wafer 10 . The holding surface is formed of a breathable member and is connected to a suction means (not shown). By operating the suction means, suction negative pressure can be generated on the holding surface to suction and hold the wafer 10 . Furthermore, the cutting device 30 is provided with control means and display means (not shown).

As shown in FIG. 5 , on the outer periphery of the wafer table 36 a of the dicing device 30 , when the frame unit U is placed and held on the wafer table 36 a, a plurality of frame units (four in this embodiment) are arranged at equal intervals. ) The frame support portion 36b of the support frame F. The frame support part 36b is provided with a gripping plate 36c that grips the frame F and is disposed rotatably.

When performing this wafer protruding step, as shown in FIG. 5 , the frame unit U is placed on the wafer stage 36 a in a state where the holding plate 36 c of the frame support part 36 b is opened. Next, the holding plate 36c of the frame support part 36b is rotated in the direction indicated by the arrow R2 in Fig. 6(a). Thereby, as shown in Figure 6(a), the rotating holding plate 36c is engaged with the frame F. As shown in Figure 6(b), the frame F descends in the direction indicated by arrow R3 and is supported by the frame. The portion 36b supports the frame F, and when viewed from the side, the wafer 10 protrudes upward from the frame F, and the protruding step is completed.

In this embodiment, by previously performing a groove forming step on the frame unit U, appropriate grooves (for example, any one of the grooves 100 to 120 ) are formed in the area of the sheet Ta between the wafer 10 and the frame F. or combination), therefore in the protruding step, when the frame F is pressed down by the holding plate 36c of the frame support portion 36b, the above-mentioned groove formed in the sheet T relaxes the pulling force in the protruding step. The tensile stress allows the wafer 10 to appropriately protrude from the frame F even when the sheet T is formed from a material with a low elongation rate.

As described above, if the protruding step has been performed on the wafer stage 36 a of the dicing device 30 , the processing step of processing the protruded wafer 10 is performed. In this embodiment, alignment is performed using the above-mentioned imaging means 37, and the position of the planned division line 14 formed on the front surface 10a of the wafer 10 is detected by this alignment. Next, based on the position information of the planned division line 14 detected by the imaging means 37, a moving means (not shown) is operated to move the wafer table 36a and the cutting means 38 in the X-axis direction, Y The axis direction and the Z-axis direction move relatively, as shown in FIG. 7 , the cutting blade 38 a of the cutting means 38 is rotated at high speed in the direction shown by arrow R4 , and as shown in FIG. 7 , the cutting blade 38 a of the cutting means 38 is cut from the front surface 10 a of the wafer 10 The wafer stage 36 a is fed and processed in the X-axis direction and the Y-axis direction to form dicing grooves along all the planned division lines 14 of the wafer 10 , and the processing step ends. In this embodiment, since the frame F is supported by the frame support part 36b and the protruding step is performed on the frame unit U, the wafer 10 protrudes upward from the frame F. When the dicing process is performed by the dicing blade 38a, the frame F does not will become an obstacle.

In addition, in the above-described embodiment, although the protruding step and the processing step of the present invention are implemented by the above-described cutting device 30, the present invention is not limited thereto. For example, the protruding step and the processing step of the present invention can be implemented by other processing devices equipped with the same holding means as the above-mentioned holding means 36, such as a laser processing device (not shown). In this case, the protruding step can also be implemented by the holding means, and the processing step of laser processing the wafer 10 can be carried out by a laser beam irradiation means (not shown) provided in the laser processing apparatus.

Furthermore, in the above-described embodiment, although the protruding step explained based on FIG. 6 is implemented, the processing step of processing the protruded wafer 10 is performed. However, the present invention is not limited to this, and may also be performed. A transfer step is performed in which another transfer sheet T' is adhered to the wafer 10 that has been projected through the above-mentioned protruding step, and the wafer 10 is transferred to the sheet T'.

When carrying out this transfer step, for example, a frame F' and a transfer sheet T' are prepared, and the surface of the above-mentioned sheet T' on which the adhesive layer is formed (the lower surface side in the figure) faces the surface protruding from the frame F. On the front surface 10 a of the wafer 10 (see FIG. 8( a )), the frame F′ has an opening in the center that can accommodate the wafer 10 , and the transfer sheet T′ has an opening that blocks the frame F′. In this way, it is pasted on the adhesive layer on the back of frame F'. In addition, in FIG. 8( a ), only the cross-sections of the frame F' and the sheet T' are shown for convenience of explanation. However, the frame F' and the sheet T' of this embodiment include the same frame F and sheet shown in the middle section of FIG. 1 The sheet T has the same shape.

If the above-mentioned sheet T’ and frame F’ have been prepared, as shown in Figure 8(b), the sheet T’ is lowered in the direction indicated by arrow R5 and pasted on the front surface 10a of the wafer 10. Next, as shown in FIG. 8(c) , the sheet T' is raised together with the wafer 10 in the direction indicated by the arrow R6, and the back surface 10b of the wafer 10 is peeled off from the sheet T of the frame unit U and transferred to the above-mentioned Slice T'. Through the above actions, the transfer step of the present invention is completed. In addition, in order to implement this transfer step well, it is preferable to perform an adhesion reducing step to reduce the adhesion of the sheet T to the wafer 10 before performing the above-mentioned protruding step. As a method of implementing the adhesive force reducing step, for example, it is preferable to irradiate ultraviolet rays from the back side of the sheet T or cool the sheet T before holding the frame unit U on the wafer stage 36 a in order to implement the above-mentioned protruding step. Processing of sheet T etc. Moreover, when the adhesive force reducing step is not performed, the adhesive force provided to the adhesive layer of the sheet T' can be set in advance to be stronger than the adhesive force of the adhesive layer of the sheet T adhered to the back surface 10b of the wafer 10. As described above, according to this embodiment, the groove forming step and the protruding step are performed on the frame unit U, so that in the above-mentioned transfer step, the sheet T on the peeled side does not contact the transferred sheet T'. Implement transfer steps appropriately.

10:wafer 12:Component 14: Split scheduled line 20:Laser processing device 22: Laser light irradiation method 30: Cutting device 31: Shell 32: Cassette 33: Temporary placement table 34: Means of moving out and moving in 35:Transportation means 36:Keep means 36a: Wafer table 36b: Frame support part 36c: Grip plate 37:Camera means 38: Cutting means 38a: Cutting blade 39:Cleaning device 39a: Cleaning and transportation means 100,110,120: slot F, F’: frame T, T’: thin slices

FIG. 1 is a perspective view showing a form of a frame unit according to this embodiment. FIG. 2(a) is a perspective view showing an embodiment of the groove forming step, and FIG. 2(b) is a perspective view of the frame unit in which grooves have been formed in the sheet. FIG. 3( a ) is a perspective view showing another embodiment of the groove shown in FIG. 2 , and FIG. 3( b ) is a perspective view showing another embodiment of the groove shown in FIG. 2 . Figure 4 is an overall perspective view of the cutting device. FIG. 5 is a perspective view showing a state in which the frame unit is placed on the holding means. FIG. 6( a ) is a partial side view showing the embodiment of FIG. 5 in cross section, and FIG. 6( b ) is a perspective view showing the embodiment of the protruding step. FIG. 7 is a partial side view showing an embodiment of the processing step in cross section. Figure 8(a) is a cross-sectional side view showing a partial side view of the sheet to be transferred that has been positioned on the frame unit that has been subjected to the protruding step. Figure 8(b) is a cross-sectional view that shows the sheet to be transferred that has been pasted on the frame unit. FIG. 8(c) is a partial side view showing the state of the wafer in the frame unit, showing a cross-sectional view of the state in which the transfer of the wafer has been completed.

10:wafer

10a: Front

12:Component

14: Split scheduled line

20:Laser processing device

22: Laser light irradiation method

100: slot

F:frame

T: thin slices

Ta: thin slices

U: frame unit

Claims (4)

A processing method of a frame unit. The frame unit is formed by positioning a wafer in an opening of the frame and integrating it with the frame through a thin sheet. The frame has the opening in the center for accommodating the wafer, The frame unit processing method includes a trench forming step of forming a trench in the sheet between the wafer and the frame. The method for processing a frame unit as claimed in claim 1, wherein, after the groove forming step, a wafer protruding step is performed, and the wafer protruding step is to place the frame unit on the holding means and support the frame with the frame support part and causing the wafer to protrude from the frame. The holding means includes a wafer table that supports the wafer and a frame support portion that is arranged on the outer periphery of the wafer table and supports the frame. The frame unit processing method of claim 2, wherein after the wafer protruding step, there is a processing step, and the processing step is to process the protruded wafer. The frame unit processing method of claim 2, wherein after the wafer protruding step, there is a transfer step. The transfer step is to arrange other sheets on the protruded wafer and transfer the wafer to the wafer. Other flakes.