Tape application device

Abstract

To prevent transfer of heat from an outer peripheral part of a mount table to a tape to prevent adhesion of the tape to the outer peripheral part of the mount table, and reduce wrinkles in the tape generated around an outer peripheral part of a wafer in pasting the tape.SOLUTION: A tape pasting device comprises: a mount table 21 having a wafer holding surface 21a that holds and heats a wafer W; a frame table 22 that is arranged surrounding an outer periphery of the mount table and holds a mount frame 27; a tape pasting unit that moves from one end to the other end of the wafer on the mount table while pressing a tape T supplied onto the wafer held on the wafer holding surface against the wafer, and pastes the tape to the wafer with heat of the wafer heated by the wafer holding surface; and a cooling ring member 23 that prevents heat directed to an exposed part Tb of the tape that is exposed between the mount frame and an outer peripheral surface 21b of the mount table on the outside of the wafer held on the wafer holding surface.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a tape application device, and more particularly to a tape application device used, for example, when applying a dicing tape to the front surface of a semiconductor wafer or when applying a surface protection tape to the back surface of a wafer. [Background technology]

[0002] A semiconductor wafer (hereinafter simply referred to as "wafer") has numerous circuit patterns of elements, such as bumps and fine circuits, formed on its surface. Therefore, a protective tape is attached to the wafer to prevent contamination and damage to the circuit surface during surface grinding and transportation.

[0003] In the semiconductor manufacturing field, wafers are becoming larger every year, and they are also becoming thinner to increase packaging density. To thin wafers, backgrinding is performed, which involves grinding the backside of the wafer. During grinding, a surface protection tape is applied to the wafer surface to protect the circuit surface formed on the wafer surface.

[0004] The wafer with the circuit pattern formed on its surface is finally cut into a dice pattern by dicing. During dicing, the wafer is attached to a frame by a dicing tape attached to the backside of the wafer. Next, a dicing blade of a dicing machine performs a half cut, cutting the wafer to the middle, or a full cut, cutting the wafer completely but cutting the dicing tape partway through.

[0005] Before applying the dicing tape to the backside of the wafer, a die attach film tape (generally referred to as a "DAF tape") may be applied to the backside of the wafer. The DAF tape serves as an adhesive for the bottom surface of the die during die bonding after dicing. Alternatively, a dicing tape (generally referred to as a "DC tape") with a die attach film (DAF) pre-applied that is approximately the same shape as the wafer may be used. Hereinafter, unless otherwise specified, the term "tape" or "dicing tape" also includes dicing tape or die attach film tape. These tapes are typically tapes that use a polymer alloy adhesive containing a thermoplastic resin (such as a polyimide resin or an acrylic resin) and a thermosetting resin (such as an epoxy resin or a phenolic resin). These tapes are typically non-adhesive but are formed to become adhesive by heating (e.g., at 100 to 160°C).

[0006] Generally, to attach dicing tape to the backside of a wafer, a dicing tape with a width larger than the outer diameter of the wafer is used, a predetermined amount of this dicing tape is pulled out from a reel, and it is attached to the backside of a heated wafer.The dicing tape is then cut along the outer peripheral surface of the wafer to hollow out the dicing tape, thereby attaching the dicing tape to the wafer (see, for example, Patent Document 1).

[0007] Fig. 6 shows an example of a conventional tape applying device that applies tape T to the back surface (hereinafter referred to as the "tape applying surface Wa") of a wafer W. As shown in Fig. 6, the tape applying device includes a mount table 101 that horizontally holds and heats the wafer W by suction, a frame table 102 that is disposed around the periphery of the mount table 101, and tape applying means 103 that has an applying roller 103a that moves on the frame table 102 and the mount table 101 along the top surface of the wafer W held by suction on the mount table 101 from one end side to the other end side of the wafer W.

[0008] More specifically, the tape T is positioned so that, during its transition from a tape supply unit (not shown) to a tape take-up unit (not shown), it passes directly above the frame table 102 and the mount table 101. Then, during the transition of the tape T, that is, directly above the frame table 102 and the mount table 101, the application roller 103a is reciprocated between the entrance side and exit side of the tape T to press the tape T onto the wafer W, and when part of the adhesive on the adhesive surface Ta of the tape T is melted by the heat on the wafer W side, the adhesive surface Ta of the tape T is adhered to the tape application surface Wa of the wafer W, and the wafer W and the tape T are integrated together.

[0009] After the wafer W and the tape T are integrated, a cutter (not shown) is used to cut the tape T along the outer circumferential surface of the wafer W. This completes the process of attaching the tape T to the wafer W, and the wafer W can be removed from the mount table 101. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-5080 Summary of the Invention [Problem to be solved by the invention]

[0011] However, the conventional tape application device described above has the problem that heat from the mount table 101 is transferred directly from the outer periphery of the mount table 101 to the tape T, causing the tape T to adhere to the outer periphery of the mount table 101 outside the wafer W, as shown in Fig. 7. In addition, the heat from the mount table 101 is not evenly applied to the wafer W, causing the temperature to increase at the outer periphery of the wafer W, resulting in significant expansion and contraction of the tape T at the portion in contact with the outer periphery of the wafer W that has received the high heat, and this expansion and contraction causes wrinkles in the tape.

[0012] Therefore, a technical problem arises that must be solved in order to provide a tape application device that can prevent heat from being transferred from the outer periphery of the mount table to the tape when applying the tape, suppress the tape from sticking to the outer periphery of the mount table, etc., and reduce tape wrinkles that occur around the outer periphery of the wafer, and the present invention aims to solve this problem. [Means for solving the problem]

[0013] The present invention has been proposed to achieve the above object, and the invention described in claim 1 is a tape application device for applying tape to a wafer, comprising: a mount table having a wafer holding surface that holds and heats the wafer; a frame table that is disposed around the outer periphery of the mount table and holds a mount frame; tape application means that presses the tape supplied onto the wafer held on the wafer holding surface against the wafer and moves on the mount table from one end side to the other end side of the wafer, applying the tape to the wafer with heat from the wafer heated by the wafer holding surface; and heat transfer suppression means that suppresses heat from flowing toward an exposed portion of the tape that is exposed between the mount frame and an outer periphery of the mount table that is outside the wafer held on the wafer holding surface. The heat transfer suppressing means has an annular flange that covers the outer peripheral portion of the mount table that is outside the wafer held on the wafer holding surface and is disposed between the mount table and the tape. A tape application device is provided.

[0014] According to this configuration, the heat transfer suppression means suppresses heat from the outer periphery of the mount table outside the wafer held on the mount table toward the tape, so that heat is supplied to the tape mainly from the mount table side via the wafer, and heat is applied almost evenly to the tape-attached surface of the wafer. This equalizes expansion and contraction of the entire tape attached to the wafer, suppressing the occurrence of tape wrinkles. Furthermore, the heat transfer suppression means suppresses heat from the outer periphery of the mount table outside the wafer held on the mount table toward the exposed portion of the tape between the wafer and the mount frame, thereby preventing tape from adhering to the outer periphery of the mount table, etc. Furthermore, since the annular flange covers the outer periphery of the mount table outside the wafer held on the mount table and the heat transfer suppressing means is positioned between the mount table and the tape, heat transfer from the outer periphery of the mount table outside the wafer held on the mount table toward the tape is reliably suppressed, and only the heat from the mount table can be applied almost evenly to the tape via the wafer. This further equalizes the expansion and contraction of the entire tape on the mount table, eliminating partial expansion and contraction and suppressing the occurrence of tape wrinkles.

[0015] The invention described in claim 2 provides a tape application device having the configuration described in claim 1, wherein the heat transfer suppression means is arranged between the mount table and the frame table and includes a cooling ring member that flows a cooling medium in an internal space to cool the outer surface.

[0016] With this configuration, the heat transfer suppression means can suppress heat from flowing from the outer periphery of the mount table outside the wafer held on the mount table to the exposed portion of the tape between the wafer and the mount frame, and the heat from the mount table alone can be applied to the tape almost evenly via the wafer. This uniformly distributes the expansion and contraction of the entire tape on the mount table, eliminating partial expansion and contraction and suppressing the occurrence of tape wrinkles. Furthermore, the heat transfer suppression means is implemented as a cooling ring member that cools the outer surface by flowing a cooling medium through its internal space, and is positioned between the mount table and the frame table, simplifying the structure and assembly.

[0017] The invention described in claim 3 provides a tape application device having the configuration described in claim 1, wherein the heat transfer suppression means is provided on the inner surface of the frame table opposite the outer surface of the mount table, and includes a cooling ring member through which a cooling medium flows to cool the outer surface.

[0018] With this configuration, the heat transfer suppression means can suppress heat from flowing from the outer periphery of the mount table outside the wafer held on the mount table to the exposed portion of the tape between the wafer and the mount frame, and the heat from the mount table alone can be applied to the tape almost evenly via the wafer. This uniformly distributes the expansion and contraction of the entire tape on the mount table, eliminating partial expansion and contraction and suppressing the occurrence of tape wrinkles. Furthermore, the heat transfer suppression means is provided integrally with the inner periphery of the frame table as a cooling ring member that cools the outer surface by flowing a cooling medium therein, thereby simplifying the structure and assembly. [Effects of the Invention]

[0021] According to the present invention, the heat transfer suppression means suppresses heat from the outer periphery of the mount table outside the wafer held on the mount table toward the tape, and the heat from the mount table alone is applied to the tape almost evenly via the wafer, so that the expansion and contraction of the entire tape on the mount table is uniform, eliminating partial expansion and contraction and suppressing the occurrence of tape wrinkles. In addition, the heat transfer suppression means blocks heat from the outer periphery of the mount table toward the tape, preventing the tape from sticking to the outer periphery of the mount table, etc. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a cross-sectional view of a schematic configuration of a tape applying device shown as an example according to an embodiment of the present invention; [Figure 2] FIG. 2 is a partially enlarged perspective view of a tape applying portion of the tape applying device. [Figure 3] FIG. 4 is a partially enlarged perspective view of the tape attachment portion, showing the state in which the cooling ring member is removed from the tape attachment portion; [Figure 4] FIG. 3 is a schematic enlarged cross-sectional view taken along line AA in FIG. 2. [Figure 5] 3 is a schematic enlarged cross-sectional view of a portion corresponding to line AA in FIG. 2, illustrating a modified example of the tape applying unit in the tape applying device. FIG. [Figure 6] FIG. 10 is a schematic cross-sectional view illustrating an example of a conventional tape applying device. [Figure 7] 10A and 10B are cross-sectional views illustrating problems with a conventional tape application device. DETAILED DESCRIPTION OF THE INVENTION

[0023] To achieve the object of the present invention to provide a tape application device that prevents heat from being transferred from the outer periphery of a mount table to the tape during tape application, prevents the tape from sticking to the outer periphery of the mount table, and reduces tape wrinkles that occur around the outer periphery of the wafer, the tape application device is configured to apply tape to a wafer, and includes: a mount table having a wafer holding surface that holds and heats the wafer; a frame table that is arranged surrounding the outer periphery of the mount table and holds a mount frame; tape application means that presses the tape supplied to the wafer held on the wafer holding surface against the wafer and moves on the mount table from one end to the other end of the wafer, and applies the tape to the wafer using the heat of the wafer heated by the wafer holding surface; and heat transfer suppression means that suppresses heat from flowing toward the exposed portion of the tape that is exposed between the outer periphery of the mount table outside the wafer held on the wafer holding surface and the mount frame. [Example]

[0024] An embodiment of the present invention will be described in detail below with reference to the accompanying drawings. In the following embodiment, when the number, value, amount, range, etc. of components is mentioned, the number is not limited to the specific number, and may be more or less than the specific number, unless otherwise specified or when it is clearly limited to a specific number in principle.

[0025] Furthermore, when referring to the shape or positional relationship of components, etc., it includes things that are substantially similar or approximate to those shapes, etc., unless otherwise specified or when it is clearly considered otherwise in principle.

[0026] In addition, the drawings may exaggerate characteristic parts to make the features easier to understand, and the dimensional proportions of the components may not be the same as in reality. In addition, in cross-sectional views, hatching of some components may be omitted to make the cross-sectional structure of the components easier to understand.

[0027] In the following description, expressions indicating directions such as up, down, left, and right are not absolute and are appropriate when each part of the tape application device of the present invention is in the posture shown in the drawing, but if the posture changes, they should be interpreted accordingly. Furthermore, the same elements are given the same symbols throughout the description of the embodiments.

[0028] Fig. 1 is a schematic cross-sectional view of a tape application device 10 according to the present invention. The tape application device 10 shown in Fig. 1 includes a tape supply unit 11 that supplies a tape T, such as a dicing tape or a surface protection tape, to be applied to a wafer W, and a tape take-up unit 12 that takes up the tape T from the tape supply unit 11.

[0029] More specifically, a guide roll 13 that applies a predetermined tension to the tape T is provided downstream of the tape supply unit 11, and a pair of peeling rolls 14 are provided further downstream of the guide roll 13. The peeling roll 14 serves to peel off a release 15 from the tape T, and the release 15 is taken up by a release take-up unit 16. Meanwhile, downstream of the peeling roll 14 are provided guide rolls 17a and 17b that guide the tape T to the tape application unit 20, and a dancer roll 18 that applies a predetermined tension to the tape T taken up by the tape take-up unit 12.

[0030] As shown in Fig. 1, a tape application unit 20 is installed on a base 19 of the tape application device 10. Fig. 2 is a partially enlarged perspective view showing a portion of the tape application unit 20, Fig. 3 is a partially enlarged perspective view showing the tape application unit 20 with the cooling ring member 23 removed, and Fig. 4 is a schematic enlarged cross-sectional view taken along line AA in Fig. 2. In this example, the tape application unit 20 uses a dicing tape as the tape T, and includes a mount table 21, a frame table 22, the cooling ring member 23 as heat transfer suppression means, and an application roll 28.

[0031] The mount table 21 shown in FIGS. 1 to 4 is movable in the vertical direction and has a wafer holding surface 21a at its upper portion, which is circular in plan view. The wafer W can be supported on the wafer holding surface 21a by suction or other means. Furthermore, as shown in FIG. 4, a heating means 24 is provided inside the mount table 21, which can heat the tape-attached surface Wa of the wafer W held on the wafer holding surface 21a to approximately 100 to 160°C. An annular positioning wall 29 is provided on the wafer holding surface 21a, forming a recess 29a that restricts horizontal movement of the wafer W placed on the wafer holding surface 21a. The positioning wall 29 has a height approximately equal to the thickness of the wafer W. The positioning wall 29 can be replaced with any other member as long as it can restrict horizontal and rotational movement of the wafer W.

[0032] 1 to 4, the frame table 22 is a fixed table disposed so as to surround the outer periphery of the wafer holding surface 21a of the mount table 21, with an annular gap 25 provided between it and the mount table 21, and has a recess 22b on its upper surface in which a mount frame 27 is disposed. The mount frame 27 serves to hold each portion of the wafer W when the wafer W is cut into dice during dicing.

[0033] The cooling ring member 23 is an annular member located in the gap 25 between the mount table 21 and the frame table 22, adjacent to and facing the outer peripheral surface 21b of the mount table 21 and the inner peripheral surface 22a of the frame table 22. A flange 23a covering the outer peripheral portion 21c of the mount table 21 is provided on the upper inner peripheral portion, extending approximately horizontally toward a positioning wall 29 of the mount table 21. The cooling ring member 23 has an annular space 26 inside, and is provided on the outside with a plurality of refrigerant supply ports 26a and a plurality of refrigerant discharge ports 26b that communicate with the interior of the space 26. A refrigerant, such as a cooled gas or liquid, is supplied from the refrigerant supply port 26a into the space 26 of the cooling ring member 23 and discharged from the refrigerant discharge port 26b, allowing the entire cooling ring member 23 to be constantly cooled.

[0034] As shown in FIG. 1 , the tape applying section 20 includes a horizontally reciprocating applying roll 28 disposed above the mount table 21. The length of the applying roll 28 is greater than the maximum width of the wafer W and the mount frame 27. Although not shown in the drawing, the applying roll 28 is connected to, for example, an endless chain stretched over two pulleys, which are connected to a motor (not shown). The applying roll 28 is reciprocated horizontally between the pulleys by rotating the motor forward and backward. Naturally, the applying roll 28 may be reciprocated horizontally by another driving mechanism. As can be seen from FIG. 1 , the applying roll 28 moves horizontally over the wafer holding surface 21 a of the mount table 21 from one end of the wafer W across the diameter of the wafer W to the other end of the wafer W, thereby applying the tape T to the wafer W.

[0035] Although not shown, a cutter unit is provided above the tape applying section 20. The cutter unit is capable of reciprocating vertically and is provided with a rotatable cutter. After tape application, the cutter unit is moved to the wafer W, and the cutter is then rotated along the periphery of the wafer W, thereby cutting the tape T applied to the wafer W.

[0036] The tape application operation of the tape application device 10 configured as described above will now be described. Prior to application of the tape T, a wafer W is placed on the wafer holding surface 21a of the mount table 21, and a mount frame 27 is placed on the frame table 22. The wafer W placed on the mount table 21 is fixed and held in a recess 29a on the wafer holding surface 21a by suction force from the mount table 21. The wafer W fixedly placed on the wafer holding surface 21a is heated to a temperature of 100°C to 160°C by a heating means 24 provided on the mount table 21. Meanwhile, a cooling ring member 23 cooled by a refrigerant flowing through a space 26 is placed in the gap 25 between the mount table 21 and the frame table 22, substantially filling the gap 25 and covering the outer peripheral portion 21c of the mount table 21. As a result, the cooling ring member 23 cools the outer peripheral surface 21b and outer peripheral portion 21c of the mount table 21 and the positioning wall 29, respectively. Furthermore, since the frame table 22 is also separated from the mount table 21 via the cooling ring member 23, the frame table 22 is not heated by the heat of the mount table 21.

[0037] Next, once the wafer W is fixed and held on the mount table 21, the tape T is placed on standby above the tape applying unit 20, as shown in Fig. 1. Then, a predetermined amount of tape T is pulled out from the tape supply unit 11, and the pulled out tape T passes sequentially through the guide roll 13, the peeling roll 14, the guide rolls 17a and 17b, the applying roll 28, the guide rolls 17b and 17a, and the dancer roll 18, before being transferred to the tape take-up unit 12. In addition, the horizontal portion of the tape T pulled out from the peeling roll 14 and transferred onto the tape applying unit 20 is positioned directly above the mount table 21 and the frame table 22, as shown in Fig. 1.

[0038] Next, the applying roll 28 reciprocates between one end of the frame table 22 and the other end of the frame table 22 while pressing the horizontal portion of the tape T against the tape applying unit 20. When the applying roll 28 presses the tape T against the wafer W on the mount table 21, the wafer W is heated to a temperature of 100°C to 160°C by the mount table 21. This melts the adhesive on the adhesive surface Ta of the tape T where it overlaps the wafer W, and the tape T adheres to the tape applying surface Wa of the wafer W. When the tape applying surface Wa of the wafer W subsequently cools, the tape T remains attached to the tape applying surface Wa. This completes the application of the tape T to the wafer W. After that, a cutter unit (not shown) located above the tape applying unit 20 cuts the tape T attached to the wafer W along the periphery of the wafer W or the periphery of the mount table 21.

[0039] In the tape application device 10 of this embodiment, a cooling ring member 23 serving as heat transfer suppression means is provided in the gap 25 between the mount table 21 and the frame table 22. The cooling ring member 23 cools the outer peripheral surface 21b and the outer peripheral portion 21c of the mount table 21 and thermally separates the frame table 22 from the mount table 21. This prevents the exposed portion Tb of the tape T, which is exposed between the wafer W and the mount frame 27, from being directly heated by the heat of the mount table 21. In other words, the cooling ring member 23 blocks the heat from being directly directed from the outer peripheral surface 21b and the outer peripheral portion 21c of the mount table 21 to the exposed portion Tb of the tape T. Therefore, only the heat from the wafer holding surface 21a of the mount table 21 is applied almost uniformly to the tape T via the wafer W. This equalizes the overall expansion and contraction of the tape T on the mount table 21 (the tape application surface Wa of the wafer W), eliminating localized expansion and contraction of the tape T and suppressing the occurrence of wrinkles in the tape T. Furthermore, the cooling ring member 23, which is a heat transfer suppression means, blocks heat from flowing from the outer peripheral surface 21b and outer peripheral portion 21c of the mount table 21 to the exposed portion Tb of the tape T, thereby preventing the tape T from adhering to the outer peripheral surface 21b and outer peripheral portion 21c of the mount table 21. Therefore, the tape T can be adhered in a consistent state to any wafer W, thereby improving product quality.

[0040] In the above embodiment, a structure was disclosed in which the heat transfer suppression means is provided with a cooling ring member 23 formed separately from the frame table 22, filling the gap 25 between the frame table 22 and the inner peripheral surface 22a of the frame table 22 adjacent to and facing the outer peripheral surface 21b of the mount table 21, and whose outer surface is cooled by a gas or liquid cooling medium flowing through a space 26. However, the present invention is not limited to this structure. For example, as shown in FIG. 5, the heat transfer suppression means may be provided with a structure in which the cooling ring member 23 is formed integrally with the frame table 22, filling the gap 25 between the frame table 22 and the inner peripheral surface 22a of the frame table 22 adjacent to and facing the outer peripheral surface 21b of the mount table 21. In FIG. 5, the cooling ring member 23 is located inside (toward the center) the boundary indicated by the imaginary line 30 in the figure.

[0041] 2, and components denoted with the same reference numerals as those in the tape application section 20 shown in Fig. 4 correspond to the tape application section 20 shown in Fig. 4, and their functions are the same. The cooling ring member 23 serving as heat transfer suppression means in the tape application section 20 shown in Fig. 5 is provided integrally with the frame table 22 on the inner periphery thereof, thereby simplifying the structure and assembly.

[0042] Furthermore, in addition to the above, the present invention can be modified in various ways without departing from the spirit of the present invention, and it goes without saying that the present invention also covers such modifications. [Explanation of symbols]

[0043] 10: Tape application device 11: Tape supply unit (tape supply means) 12: Tape winding section 13: Guide roll 14: Peeling roll 15: Release 16: Release winding section 17a: Guide roll 17b: Guide roll 18: Dancer Roll 19: Bass 20: Tape attachment section (tape attachment means) 21: Mounting table 21a: wafer holding surface 21b: Outer surface 21c: Outer periphery 22: Frame table 22a: Inner surface 22b: recess 23: Cooling ring member (heat transfer suppression means) 23a:Tsubabe 24:Heating means 25: Gap 26: Space part 26a: Refrigerant supply section 26b: Refrigerant discharge part 27: Mounting frame 28: Paste roll 29: Positioning wall 29a: recess 30: Virtual line T: Tape Ta: Adhesive surface Tb:Exposed part W: Wafer Wa: Tape attachment surface

Claims

1. A tape application device for applying a tape to a wafer, a mount table having a wafer holding surface for holding and heating the wafer; a frame table that is disposed around the outer periphery of the mount table and that holds a mount frame; a tape applying means for pressing the tape supplied onto the wafer held on the wafer holding surface against the wafer, moving on the mount table from one end side to the other end side of the wafer, and applying the tape to the wafer by the heat of the wafer heated by the wafer holding surface; a heat transfer suppressing means for suppressing heat directed toward an exposed portion of the tape that is exposed between the mount frame and an outer peripheral portion of the mount table that is outside the wafer held on the wafer holding surface; Equipped with a tape application device characterized in that the heat transfer suppression means has an annular flange that covers the outer peripheral portion of the mount table that is outside the wafer held on the wafer holding surface and is positioned between the mount table and the tape.

2. 2. The tape application device according to claim 1, wherein the heat transfer suppression means comprises a cooling ring member disposed between the mount table and the frame table and configured to allow a cooling medium to flow through an internal space to cool the outer surface.

3. 2. The tape application device according to claim 1, wherein the heat transfer suppression means comprises a cooling ring member provided on the inner peripheral surface of the frame table opposite the outer peripheral surface of the mount table, and having a cooling medium flowing therethrough to cool the outer surface.

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