JP5691364B2 - Tape sticking device and tape sticking method - Google Patents

Description

  The present invention relates to a tape applying device and a tape applying method.

  In recent years, power semiconductor devices have been made thinner due to the need for higher performance and lower cost, and the thickness of the wafer has become extremely thin, for example, about several tens of micrometers. As described above, the thinned wafer is likely to be chipped at the end portion and easily chipped. In addition, since the mechanical strength of the entire wafer is lowered, there is a problem that cracks, chips, and deflection are likely to occur.

  In order to solve such a problem, a wafer having a rib structure on the back surface of the wafer (hereinafter referred to as a rib wafer) has been proposed. The rib wafer is produced, for example, by polishing only the central portion on the back surface side of the wafer, leaving the outer peripheral edge of the wafer. By using the rib wafer, the warpage of the wafer is greatly relieved, and the strength for holding the wafer is greatly improved when the wafer is handled in the subsequent dicing process and transport process. For this reason, cracks and chipping of the wafer can be reduced.

  FIG. 7 is a cross-sectional view schematically showing a conventional tape applicator. In the process of dicing a rib wafer into chips, it is known to perform a process of applying an adhesive tape (dicing tape) to the back surface of the wafer in order to prevent wafer misalignment and chip scattering during dicing. For example, in the tape applicator shown in FIG. 7, when the adhesive tape 102 is applied to the flat wafer 101, pressure is applied from above the adhesive tape 102 superimposed on the back surface side of the wafer 101 by the roller 103, and the back surface of the wafer 101. The adhesive tape 102 is pressure-bonded to the surface.

  When such a sticking method is applied to a rib wafer, for example, air bubbles may enter between the back surface of the rib wafer and the adhesive tape due to irregularities on the back surface of the rib wafer (hereinafter, bubbles are generated in the adhesive tape), Inability to uniformly apply pressure to the front and back surfaces causes problems such as wrinkling of the adhesive tape.

  Therefore, as a sticking method that does not cause bubbles or wrinkles in the adhesive tape, the adhesive tape is pressed with an adhesive member that swirls in a spiral shape from the center of the recess formed on the back surface of the rib wafer to the back surface of the rib wafer. A method has been proposed in which a pressure-sensitive adhesive tape is pushed into and stuck to the formed recess (for example, see Patent Document 1 below).

  In addition, as a tape applicator that does not generate air bubbles in the adhesive tape, a base having an airtight space inside, and the airtight space are divided into first and second airtight spaces, and the tape is applied to the first airtight space side. A vacuum is formed in each of the elastic sheet of the elastic body for mounting the component to be attached, the tape attached to the base so as to be separated from the component mounted on the elastic sheet by a predetermined distance, and the first and second airtight spaces. There has been proposed an apparatus including first and second vacuum pumps (see, for example, Patent Document 2 below).

  Further, as another device, a base, an upper lid that covers the base and forms an airtight space between the base, the airtight space on the base side, and the upper lid side And an elastic sheet of an elastic body on which a component for attaching a tape to the airtight space side of the upper lid side is placed, and an adhesive sheet placed on the elastic sheet and supporting the wafer away from the elastic sheet There has been proposed an apparatus including a jig for use and first and second vacuum pumps that respectively change the internal pressure of the airtight space on the base side and the airtight space on the upper lid side (see, for example, Patent Document 3 below). ).

JP 2008-04-2016 A JP 2005-026377 A JP 2006-310338 A

  However, the technique described in Patent Document 1 described above has the following problems. FIG. 8 is a cross-sectional view schematically showing another example of a conventional tape applicator. In the tape applicator shown in FIG. 8, when the adhesive tape 112 is applied to the back side of the rib wafer 111, the entire front surface of the rib wafer 111 contacts the support table 113. For this reason, when the adhesive tape 112 is pressed against the back surface of the rib wafer 111 by the affixing member 114, the front surface of the rib wafer 111 on which the circuit is formed may be damaged, resulting in an element failure. The same problem occurs in Patent Document 2 described above.

  In the technique described in Patent Document 3 described above, the wafer is pushed up together with the plate placed with the front side of the wafer facing down, and the back side of the wafer is pressed against the adhesive tape held above the wafer. Yes. Since pressure is not directly applied to the wafer and pressed against the adhesive tape, when the technique described in Patent Document 3 is applied to the rib wafer, bubbles and wrinkles are generated on the entire back surface according to the unevenness of the back surface of the rib wafer. There is a possibility that the adhesive tape cannot be applied. In addition, when the techniques described in Patent Documents 2 and 3 described above are applied to a rib wafer, the wafer is locally pressed by the unevenness on the back surface of the wafer, causing cracks and chipping in the wafer, resulting in damage to the wafer. There is a risk that.

  An object of the present invention is to provide a tape sticking apparatus and a tape sticking method that do not damage the surface on which a circuit of a wafer is formed in order to solve the above-described problems caused by the prior art. It is another object of the present invention to provide a tape applying apparatus and a tape applying method for applying a tape to a wafer without generating bubbles or wrinkles on the tape. An object of the present invention is to provide a tape attaching apparatus and a tape attaching method for attaching a tape to the surface of a wafer without damaging the wafer.

In order to solve the above-described problems and achieve the object of the present invention, a tape sticking device according to the present invention is a tape for sticking an adhesive tape to a semiconductor wafer in which a concave portion thinner than an outer peripheral end portion is formed in a central portion of a back surface. A sticking apparatus, a wafer support for supporting an outer peripheral end of the front side of the semiconductor wafer, and a decompression means for decompressing a first sealed space on the wafer support where the semiconductor wafer is supported And a tape holding jig for holding the adhesive tape away from the back surface of the semiconductor wafer, and a pressure on the front surface side of the semiconductor wafer supported by the wafer support table above the wafer support table. A pressing means for applying, a sticking member that moves in a direction perpendicular to the surface of the semiconductor wafer and pushes the adhesive tape into a recess on the back surface of the semiconductor wafer, and operates the pressing means. And a control means for operating the affixing member, wherein the wafer support has a groove portion at a position facing the central portion on the front surface side of the semiconductor wafer, At least a part of the outer peripheral end thicker than the portion, and the pressurizing means is formed between the semiconductor wafer and the wafer support base in a state where the first sealed space is decompressed by the decompressing means. Air is introduced into the second sealed space, the air pressure in the second sealed space is raised above that of the first sealed space, and the air pressure generated by the pressure difference supports the wafer support table. It is characterized in that pressure is applied to the front side of the semiconductor wafer .

The tape adhering apparatus according to this invention is the invention described above, the sticking member is characterized in that it consists of elastic material.

Further, the tape adhering apparatus according to this invention, in the invention described above, the sticking member is characterized in that it has a circular planar shape of the wider diameter than the diameter of the semiconductor wafer.

Further, the tape adhering apparatus according to this invention, in the invention described above, the sticking member is characterized by having a sectional shape gradually increasing thickness toward the center from the periphery.

Further, the tape adhering apparatus according to this invention, in the invention described above, the tape holding jig is characterized in that for holding the adhesive tape and the adhesive surface on the semiconductor wafer side.

Moreover, the tape sticking device according to the present invention is the above-described invention, wherein the pressurizing means is provided at a central portion on the front surface side of the semiconductor wafer in which a surface element structure is formed at the central portion of the front surface. It is characterized by applying pressure .

Further, in the tape applicator according to the present invention, in the above-described invention, the control unit is configured so that a pressure substantially equal to the pressure applied by the pressurizing unit is applied to the back side of the semiconductor wafer. The sticking member is lowered vertically .

The tape adhering apparatus according to this invention is the invention described above, the pressure reducing means, characterized in that said first sealed space to a vacuum or reduced pressure state.

Further, in order to solve the above-described problems and achieve the object of the present invention, a tape applying method according to the present invention applies an adhesive tape to a semiconductor wafer in which a concave portion thinner than an outer peripheral end portion is formed at the center of the back surface. A method of applying a tape, a wafer mounting step of mounting the semiconductor wafer on a wafer support that supports an outer peripheral edge of the semiconductor wafer with a front side facing down, and an upper side of the semiconductor wafer A holding step for holding the adhesive tape away from the semiconductor wafer, a depressurizing step for depressurizing the first sealed space on which the semiconductor wafer is placed on the wafer support, and the first sealing Air is introduced into a second sealed space formed between the semiconductor wafer and the wafer support in a state where the space is depressurized, and the pressure of the second sealed space is set to be higher than that of the first sealed space. Raise, The air pressure caused by the pressure difference, together with applying pressure to the front surface side of the semiconductor wafer, wherein provided above the pressure-sensitive adhesive tape, the adhering member which moves in the direction perpendicular to the surface of the semiconductor wafer, A control step of pressing and sticking the adhesive tape into a recess on the back surface of the semiconductor wafer, and in the wafer mounting step, a groove portion provided on the wafer support base and a front surface side of the semiconductor wafer The semiconductor wafer is placed so as to face the central portion of the semiconductor wafer, and at least a part of the outer peripheral end portion thicker than the central portion of the semiconductor wafer is supported by the wafer support.

The tape sticking method according to this invention is the invention described above, the sticking member is characterized in that it consists of elastic material.

The tape sticking method according to this invention is the invention described above, the sticking member is characterized in that it has a circular planar shape of the wider diameter than the diameter of the semiconductor wafer.

The tape sticking method according to this invention is the invention described above, the sticking member is characterized by having a sectional shape gradually increasing thickness toward the center from the periphery.

The tape sticking method according to this invention is the invention described above, in the holding step, adhesive side down holding the adhesive tape, in the control step, the adhesive surface of the adhesive tape by the sticking member Is pressed against the back side of the semiconductor wafer.

Further, in the tape applying method according to the present invention, in the above-described invention, in the control step, the pressure is applied to the central portion on the front surface side of the semiconductor wafer in which the surface element structure is formed in the central portion of the front surface. It is characterized by applying .

Further, in the tape attaching method according to the present invention, in the above-described invention, in the control step, a pressure that is substantially the same as the pressure applied to the central portion on the front surface side of the semiconductor wafer is a back surface of the semiconductor wafer. The sticking member is vertically lowered so as to be on the side.

The tape sticking method according to this invention is the invention described above, in the decompression process, characterized in that said first sealed space to a vacuum or reduced pressure state.

  According to the above-described invention, only the outer peripheral end of the front side of the semiconductor wafer is supported by the wafer support. Further, when the adhesive tape is applied to the back surface side of the semiconductor wafer having a recess thinner than the outer peripheral edge at the center of the back surface, the pressure of the air introduced into the second sealed space causes the semiconductor wafer to Apply pressure to the front side. For this reason, the parts constituting the tape attaching device such as the wafer support do not contact the surface element structure formed at the center of the front surface of the semiconductor wafer.

  Also, when only the outer peripheral edge of the front side of the semiconductor wafer is supported, the air pressure applied to the front side of the semiconductor wafer is not equal to the pressure applied by the adhesive member applied to the back side of the semiconductor wafer. However, it is possible to avoid applying pressure exceeding the pressure for applying the adhesive tape to the concave portion thinner than the outer peripheral end portion of the semiconductor wafer.

  Further, the pressure applied to the front surface side of the semiconductor wafer by the pressurizing means and the pressure applied to the back surface side of the semiconductor wafer by the attaching member can be applied almost simultaneously. These pressures are directly applied to the front and back surfaces of the semiconductor wafer. For this reason, pressure can be uniformly applied to the front surface and the back surface of the semiconductor wafer.

Moreover, according to the above-described invention , when the adhesive tape is applied to the back surface side of the semiconductor wafer, the attaching member can be brought into contact with the entire back surface along the unevenness of the back surface of the semiconductor wafer. Thereby, the adhesive tape can be pushed into the step portion formed at the boundary between the recess on the back surface of the semiconductor wafer and the outer peripheral end.

Further, according to the above-described invention , when the adhesive tape is applied to the back surface side of the rib wafer 1, the adhesive tape can be gradually pressed from the vicinity of the center of the concave portion on the back surface of the semiconductor wafer toward the outer peripheral end portion.

  According to the tape sticking apparatus and the tape sticking method of the present invention, there is an effect that the tape can be stuck on the wafer surface without damaging the surface on which the circuit of the wafer is formed. In addition, there is an effect that the tape can be attached to the surface of the wafer without generating bubbles or wrinkles on the tape. The tape can be applied to the surface of the wafer without damaging the wafer.

It is explanatory drawing which shows the tape sticking apparatus concerning embodiment. It is explanatory drawing which shows the time of operation | movement of the tape sticking apparatus concerning embodiment. It is explanatory drawing which shows the principal part of the semiconductor wafer supported by the wafer support stand. It is explanatory drawing which shows the principal part of the semiconductor wafer supported by the wafer support stand. It is explanatory drawing which shows another example of the cross-sectional shape of a sticking member. It is explanatory drawing which shows the atmospheric | air pressure change concerning a semiconductor wafer, and a pressure change. It is sectional drawing which shows the conventional tape sticking apparatus typically. It is sectional drawing which shows typically another example of the conventional tape sticking apparatus.

  Exemplary embodiments of a tape applicator and a tape applicator according to the present invention will be explained below in detail with reference to the accompanying drawings. Note that, in the following description of the embodiments and the accompanying drawings, the same reference numerals are given to the same components, and duplicate descriptions are omitted.

(Embodiment)
FIG. 1 is an explanatory diagram illustrating a tape applying device according to an embodiment. Moreover, FIG. 2 is explanatory drawing which shows the time of operation | movement of the tape sticking apparatus concerning Embodiment. Here, a semiconductor having a stepped shape (hereinafter referred to as a concave portion) 3 is formed by thinning the central portion while leaving the entire circumference or a part of the outer peripheral end portion on the back surface side of the semiconductor wafer 1 as a reinforcing portion (rib portion) 2. A description will be given using a wafer (hereinafter referred to as a rib wafer) 1. A surface element structure (not shown) is formed at the center of the front surface 4 of the rib wafer 1.

  The tape sticking device according to the embodiment is a device for sticking the adhesive tape 5 to the entire back surface side including the concave portion 3 on the back surface of the rib wafer 1. For example, the tape applicator according to the embodiment is used when adhering an adhesive tape (dicing tape) 5 to the back surface of a wafer in order to prevent misalignment of a semiconductor wafer and scattering of chips during dicing.

  As shown in FIG. 1, the tape applicator according to the embodiment includes a stage 11 on which the rib wafer 1 is placed, a lid 12 that covers the rib wafer 1 on the stage 11, and a wafer support 13 that supports the rib wafer 1. , A vacuum generator (decompression unit) 14 for evacuating the space (first sealed space) 21 sealed by the stage 11 and the lid 12, and a pressurizing device (pressurizing unit) for applying pressure to the rib wafer 1 from the wafer support 13 side. Pressure means) 15, a frame (tape holding jig) 16 for holding the adhesive tape 5 to be attached to the rib wafer 1, an attaching member 17 for pressing the adhesive tape 5 into the recess 3 on the back surface of the rib wafer 1, and a vacuum generator 14. Control means for controlling the pressure device 15 and the sticking member 17.

  A wafer support 13 is embedded in the groove formed in the stage 11. The wafer support 13 may be provided on the stage 11, for example. A space where the rib wafer 1 is placed on the stage 11 is a space (first sealed space) 21 sealed by the stage 11 and the lid 12. That is, the rib wafer 1 is placed in the first sealed space 21 and supported by the wafer support 13.

  On the stage 11, there are provided guide pins 31 that contact the side surface of the rib wafer 1 and fix the position of the rib wafer 1 when the rib wafer 1 is placed. A pedestal (hereinafter referred to as a frame pedestal) 32 for installing the frame 16 is provided on the stage 11 at a position farther from the wafer support base 13 than the guide pins 31.

  The wafer support 13 supports only the outer peripheral end portion on the front surface 4 side of the rib wafer 1 placed with the front surface down. Further, the wafer support base 13 has a groove portion 18 having a width narrower than the diameter of the rib wafer 1. The groove 18 of the wafer support 13 is covered with the rib wafer 1 when the rib wafer 1 is placed. That is, the wafer support 13 is a portion protruding from the groove portion 18 and supports only the rib portion 2 on the front surface 4 side of the rib wafer 1.

  The groove 18 forms a closed space (second sealed space) 22 between the semiconductor wafer and the wafer support table 13 when the semiconductor wafer is placed on the wafer support table 13. That is, as shown in FIG. 1, the second sealed space 22 is a closed space composed of the rib wafer 1 and the groove portion 18 of the wafer support 13.

  Further, the groove portion 18 of the wafer support 13 contacts the surface element structure provided in the central portion on the front surface 4 side of the rib wafer 1 when the rib wafer 1 is placed with the front surface facing down. It has a width that is not wide enough. Thereby, as shown in FIG. 1, the wafer support base 13 is not in contact with the front surface element structure provided in the central portion on the front surface 4 side of the rib wafer 1, but on the front surface 4 side. Only the rib 2 is supported.

  Desirably, the groove 18 of the wafer support 13 has a width wider than the width of the recess 3 of the rib wafer 1. The reason is that when the pressure applied to the front surface and the back surface of the rib wafer 1 is not equal, a pressure exceeding the pressure for applying the adhesive tape 5 is applied to the thinned portion of the recess 3 of the rib wafer 1. This is because it can be avoided. 3 and 4 are explanatory views showing the main part of the semiconductor wafer supported by the wafer support. That is, as shown in FIGS. 3 and 4, the width of the groove 18 is such that the wafer support 13 supports the surface of part (see FIG. 3) or all (see FIG. 4) of the rib 2 of the rib wafer 1. It is preferable that the width is as large as possible.

  Inside the stage 11, a first ventilation hole 33 and a second ventilation hole 34 are provided. The first ventilation hole 33 is provided in a portion of the stage 11 where the wafer support 13 is not provided. The first ventilation hole 33 is connected to the first sealed space 21. The first ventilation hole 33 is connected to a vacuum generator 14 provided outside the stage 11 through a pipe provided inside the stage 11.

  The second ventilation hole 34 is provided in the groove 18 of the wafer support 13. That is, the second ventilation hole 34 is connected to the second sealed space 22. The second ventilation hole 34 passes through the wafer support 13 and reaches the stage 11, and is connected to the pressurizing device 15 via a pipe provided inside the stage 11.

  The vacuum generator 14 places the first sealed space 21 in a vacuum or reduced pressure state through a pipe (vacuum system) connected to the first ventilation hole 33. That is, the vacuum generator 14 depressurizes the first sealed space 21 on which the rib wafer 1 is placed and the adhesive tape 5 is held.

  The pressurizing device 15 introduces pressure into the second sealed space 22 through a pipe connected to the second ventilation hole 34. For example, the pressurizing device 15 introduces air into the second sealed space 22, raises the air pressure in the second sealed space 22, and raises the semiconductor wafer by the air pressure generated by the pressure difference. Apply pressure from the front side.

  The frame 16 is fixed to the adhesive tape 5 in advance without slack. In this state, the adhesive tape 5 is placed on the frame base 32 with the adhesive surface of the adhesive tape 5 facing the rib wafer 1. By installing the frame 16 on the frame base 32, the adhesive tape 5 is held away from the rib wafer 1 on the side of the wafer support 13 where the rib wafer 1 is supported. As the frame 16, for example, a ring frame made of stainless steel may be used.

  The affixing member 17 is provided at a position facing the rib wafer 1 with the adhesive tape 5 in between so as to be movable up and down by the drive unit 19. The sticking member 17 is attached to the lid 12 via, for example, the drive unit 19 and moves perpendicularly to the surface of the semiconductor wafer.

  The control means controls, for example, the vacuum generator 14, the pressure device 15, the application member 17, and the like provided in the tape application device by executing a program prepared in advance on a computer such as a personal computer or a workstation. .

  Specifically, the control means (not shown) presses the back surface side of the rib wafer 1 against the adhesive tape 5 by the pressure device 15, and pushes the adhesive tape 5 into the concave portion 3 on the back surface of the rib wafer 1 by the attaching member 17. Control. Specifically, the control unit 17 applies the adhesive member 17 so that a pressure substantially equal to the air pressure is applied to the back surface side of the rib wafer 1 in accordance with the increase in the air pressure in the second sealed space 22 by the pressurizing device 15. Is lowered vertically.

  The affixing member 17 is made of a material that is deformed so as to be in contact with the entire back surface of the rib wafer 1 along an uneven shape formed on the back surface side of the rib wafer 1. The affixing member 17 is made of an elastic body such as an EPDM (Ethylene Propylene Diene Monomer) sponge, for example. That is, as described above, when the sticking member 17 is lowered by the control means and pressed against the back surface side of the rib wafer 1, the sticking member 17 is elastically deformed according to the uneven shape on the back surface side of the rib wafer 1. The adhesive tape 5 is deformed by the sticking member 17 in accordance with the uneven shape on the back surface side of the rib wafer 1 and is pushed into the step portion 6 formed at the boundary between the center portion of the back surface of the rib wafer 1 and the rib portion 2. Affixed to the entire back surface of the rib wafer 1 (see FIG. 2).

  The sticking member 17 has a cylindrical shape, and has a circular planar shape with a diameter wider than the diameter of the rib wafer 1. And the sticking member 17 covers the whole back surface of the rib wafer 1 when it descends by the drive part 19 and contacts the back surface side of the rib wafer 1. Thereby, when sticking the adhesive tape 5 on the back surface side of the rib wafer 1, the adhesive tape 5 can be pressed not only on the recess 3 on the back surface of the rib wafer 1 but also on the surface of the rib portion 2 on the back surface side of the rib wafer 1. .

  FIG. 5 is an explanatory diagram showing another example of the cross-sectional shape of the sticking member. As shown in FIG. 5, an adhesive member 37 having a cross-sectional shape that gradually increases in thickness from the outer peripheral portion toward the central portion may be used. By using the sticking member 37, the adhesive tape 5 can be gradually pressed from the vicinity of the center of the recess 3 on the back surface of the rib wafer 1 toward the rib portion 2 side.

  Next, the operation of the tape applicator according to the embodiment will be described. First, as shown in FIG. 1, the wafer is placed on the wafer support 13 provided on the stage 11 so that the front surface 4 side of the rib wafer 1 faces down (wafer placing process). At this time, the rib wafer 1 is placed in a state where only the outer peripheral end on the front surface 4 side is in contact with the wafer support 13. That is, the groove portion 18 of the wafer support base 13 is covered by the rib wafer 1, and only the rib wafer 1 is supported by the portion protruding from the groove portion 18 of the wafer support base 13.

  Next, the frame 16 to which the adhesive tape 5 is previously fixed is placed on the frame base 32 with the adhesive surface of the adhesive tape 5 facing down (holding step). The height of the frame pedestal 32 is high enough that the adhesive tape 5 fixed to the frame 16 does not contact the rib wafer 1. Thereby, the adhesive tape 5 is held in a state separated from the rib wafer 1. Next, the stage 12 is covered with a lid 12 so that the space in which the rib wafer 1 is supported becomes the first airtight space 21.

  Next, the inside of the first sealed space 21 is decompressed by the decompression means 14 via a pipe (vacuum system) connected to the first ventilation hole 33 (a decompression step). Thereby, the rib wafer 1 and the adhesive tape 5 are placed in a vacuum atmosphere, for example. That is, both the space on the front surface 4 side and the space on the back surface side of the rib wafer 1 are evacuated. Here, the vacuum may be reduced to a pressure lower than the atmospheric pressure without evacuating until the vacuum is reached.

  For example, air is introduced into the second sealed space 22 formed between the rib wafer 1 and the wafer support 13 in the first sealed space 21 in a vacuum state, so that the front surface 4 of the rib wafer 1 is obtained. While applying pressure to the side, the sticking member 17 provided above the pressure-sensitive adhesive tape 5 is vertically lowered, and the pressure-sensitive adhesive tape 5 is pushed into the concave portion on the back surface of the rib wafer 1 for sticking (control process).

  In other words, in the control step, the rib wafer 1 is caused by the pressure difference between the front surface 4 side and the back surface side of the rib wafer 1 that is generated on the front surface 4 side of the rib wafer 1 as the air pressure in the second sealed space 22 increases. Apply air pressure in the direction of pushing up. Thereby, the back surface side of the rib wafer 1 is pressed against the adhesive surface of the adhesive tape 5. At the same time, pressure is applied to the back surface side of the rib wafer 1 in the direction of pushing down the rib wafer 1 by the sticking member 17. Thereby, the adhesive surface of the adhesive tape 5 is pressed against the back surface side of the rib wafer 1. Thus, in the control process, pressure is directly applied to the front surface and the back surface of the rib wafer 1 almost simultaneously.

  In the control step, the air pressure applied to the front surface 4 side of the rib wafer 1 and the pressure applied to the back surface side of the rib wafer 1 are preferably set to be approximately the same magnitude. That is, it is preferable to gradually increase the pressure applied by the sticking member 17 as the air pressure in the second sealed space 22 increases. The reason for this is that pressure can be uniformly applied to the front surface 4 and the back surface of the rib wafer 1, and the adhesive tape 5 is applied to the back surface side of the rib wafer 1 without causing cracks or chips to the rib wafer 1. Because it can be done.

  Thereby, as shown in FIG. 2, the adhesive tape 5 is affixed to the entire back surface of the rib wafer 1 along the uneven shape of the back surface of the rib wafer 1. That is, the pressure-sensitive adhesive tape has almost no gap on the surface of the recess 3 on the back surface of the rib wafer 1, the step portion 6 formed at the boundary between the central portion of the back surface of the rib wafer 1 and the rib portion 2, 5 is affixed.

  FIG. 6 is an explanatory diagram showing changes in pressure and pressure applied to the semiconductor wafer. In FIG. 6, the pressure on the back surface side of the rib wafer 1 (hereinafter referred to as “back surface pressure”) 41 and the pressure on the front surface side (hereinafter referred to as “back surface pressure”) in the tape applying device during operation of the tape applying device according to the embodiment. And the pressure when the adhesive tape 5 is pressed against the rib wafer 1 by the sticking member (hereinafter, referred to as pressure by the sticking member) 43.

  After the rib wafer 1 and the adhesive tape 5 are installed in the tape applicator, the pressure 41 on the back side and the air pressure 42 on the front surface are maintained at atmospheric pressure until the time 51 when the operation of the tape applicator is started. The When the operation of the tape applying device is started, first, the inside of the first sealed space 21 is depressurized by the vacuum generator 14. Thereby, the air pressure 41 on the back surface side and the air pressure 42 on the front surface side are reduced by substantially the same amount of change, and then maintained in a vacuum state or a reduced pressure state.

  Next, air is introduced into the second sealed space 22 by the pressurizing device 15, and the pressure 42 on the front surface side starts to rise from the time point 52. At the same time, the affixing member is pressed against the back side of the rib wafer 1, and the pressure 43 by the affixing member is increased with a change amount substantially the same as the change amount of the atmospheric pressure 42 on the front side. In this state, for example, up to a preset time 53 (or a preset set value), pressure of substantially the same magnitude is continuously applied to the front surface 4 side and the back surface side of the rib wafer 1. Further, after maintaining the pressure 42 on the front surface side and the pressure 43 by the sticking member until, for example, a time point 54 after a predetermined time has elapsed, the inside of the first sealed space 21 is returned to the atmospheric pressure. Thereby, the air pressure 41 on the back surface side and the air pressure 42 on the front surface side return to the air pressure at the time 51 when the operation of the tape applying device is started, and the operation of the tape applying device is ended.

  As described above, according to the embodiment, only the rib portion 2 on the front surface 4 side of the rib wafer 1 is supported by the wafer support base 13. Further, when the adhesive tape 5 is attached to the back surface side of the rib wafer 1, pressure is applied to the front surface 4 side of the rib wafer 1 by the pressure of the air introduced into the second sealed space 22. For this reason, components constituting the tape attaching device such as the wafer support 13 do not contact the surface element structure formed at the center of the front surface 4 of the rib wafer 1. Thereby, the adhesive tape 5 can be stuck on the back surface side of the rib wafer 1 so as not to damage the front surface 4 on which the circuit (surface element structure) of the rib wafer 1 is formed.

  Further, since only the rib portion 2 on the front surface 4 side of the rib wafer 1 is supported, the air pressure applied to the front surface 4 side of the rib wafer 1 and the pressure by the sticking member 17 applied to the rear surface side of the rib wafer 1 are reduced. Even when they are not equal, it is possible to avoid applying pressure exceeding the pressure for applying the adhesive tape 5 to the concave portion 3 thinner than the rib portion 2 of the rib wafer 1.

  Further, the pressure applied to the front surface 4 side of the rib wafer 1 by the pressurizing device 15 and the pressure applied to the rear surface side of the rib wafer 1 by the sticking member 17 can be applied almost simultaneously and in substantially the same magnitude. Further, these pressures are directly applied to the front surface and the back surface of the rib wafer 1. For this reason, pressure can be uniformly applied to the front surface and the back surface of the rib wafer 1. Thereby, it is possible to reduce the occurrence of bubbles and wrinkles in the adhesive tape 5.

  The sticking member 17 is made of the above-described material and has the above-described planar shape. For this reason, when sticking the adhesive tape 5 on the back surface side of the rib wafer 1, the sticking member 17 can be brought into contact with the entire back surface along the unevenness of the back surface of the rib wafer 1. Thereby, the adhesive tape 5 can be pushed into the step portion 6 formed at the boundary between the recess 3 and the rib portion 2 on the back surface of the rib wafer 1.

  Moreover, the sticking member 37 has the cross-sectional shape mentioned above. For this reason, when sticking the adhesive tape 5 on the back surface side of the rib wafer 1, the adhesive tape 5 can be gradually pressed from the vicinity of the center of the recess 3 on the back surface of the rib wafer 1 toward the rib portion 2. Thereby, it is possible to reduce the occurrence of wrinkles in the adhesive tape 5.

  In the present invention, the case where the adhesive tape is applied to the back surface side of the rib wafer is described as an example. However, the present invention is not limited to the above-described embodiment, and the adhesive tape may be applied to the front surface side of the rib wafer. It can be applied to a flat semiconductor wafer. In addition, although the semiconductor wafer having the surface element structure formed on the front surface side is used, the present invention is not limited to this, and a semiconductor wafer on which the surface element structure is not yet formed on the front surface side may be used. . Further, the present invention is not limited to the case where a dicing tape is attached to the back side of the semiconductor wafer, but can be applied to the case where various tapes are attached to the surface of the semiconductor wafer.

  As described above, the tape sticking apparatus and the tape sticking method according to the present invention are used for sticking an adhesive tape (dicing tape) to the back surface of a wafer in order to prevent misalignment of a semiconductor wafer and scattering of chips during dicing. Useful.

DESCRIPTION OF SYMBOLS 1 Rib wafer 2 The peripheral edge part (rib part) of a rib wafer
DESCRIPTION OF SYMBOLS 3 Concave part of the back surface of a rib wafer 4 Front surface of a rib wafer 5 Adhesive tape 11 Stage 12 Lid 13 Wafer support stand 14 Vacuum generator 15 Pressurizer 16 Frame 17 Sticking member 18 Groove part 19 Drive part

Claims (16)

A tape attaching device for attaching an adhesive tape to a semiconductor wafer in which a concave portion thinner than an outer peripheral end portion is formed at the center of the back surface,
A wafer support for supporting an outer peripheral end of the front side of the semiconductor wafer;
Decompression means for decompressing a first sealed space in which the semiconductor wafer on the wafer support is supported;
Above the wafer support, a tape holding jig for holding the adhesive tape away from the back surface of the semiconductor wafer,
Pressurizing means for applying pressure to the front surface side of the semiconductor wafer supported by the wafer support;
An affixing member that moves in a direction perpendicular to the surface of the semiconductor wafer and pushes the adhesive tape into a recess on the back surface of the semiconductor wafer;
Control means for operating the pressing member and operating the sticking member;
With
The wafer support has a groove at a position facing the central portion on the front surface side of the semiconductor wafer, and supports at least a part of the outer peripheral end portion thicker than the central portion of the semiconductor wafer ,
The pressurizing means introduces air into a second sealed space formed between the semiconductor wafer and the wafer support base in a state where the first sealed space is decompressed by the decompressing means, and the first The air pressure of the second sealed space is raised from that of the first sealed space, and pressure is applied to the front surface side of the semiconductor wafer supported by the wafer support by the air pressure generated by the pressure difference. A tape applicator. The tape sticking device according to claim 1, wherein the sticking member is made of an elastic body. The sticking member, the tape adhering apparatus according to claim 1 or 2, characterized in that it has a circular planar shape of the wider diameter than the diameter of the semiconductor wafer. The tape sticking device according to any one of claims 1 to 3 , wherein the sticking member has a cross-sectional shape that gradually increases in thickness from an outer peripheral part toward a central part. The tape sticking apparatus according to any one of claims 1 to 4 , wherein the tape holding jig holds the adhesive tape with an adhesive surface facing the semiconductor wafer. The pressurizing means may be any of claims 1-5, characterized in that applying pressure to the central portion of the front surface side of the semiconductor wafer surface element structure is formed in the central portion of the front surface The tape applicator according to one. 7. The control device according to claim 6 , wherein the control member lowers the sticking member vertically so that a pressure substantially equal to the pressure applied by the pressurizing device is applied to the back surface side of the semiconductor wafer. The tape applicator described. The tape sticking device according to any one of claims 1 to 7 , wherein the decompression unit places the first sealed space in a vacuum or a decompressed state. A tape attaching method for attaching an adhesive tape to a semiconductor wafer in which a concave portion thinner than the outer peripheral end portion is formed in the center portion of the back surface,
A wafer mounting step of mounting the semiconductor wafer on a front surface side down on a wafer support that supports the outer peripheral edge of the semiconductor wafer;
A holding step for holding the adhesive tape apart from the semiconductor wafer above the semiconductor wafer;
A depressurizing step of depressurizing the first sealed space on which the semiconductor wafer is placed on the wafer support;
In a state where the first sealed space is decompressed, air is introduced into a second sealed space formed between the semiconductor wafer and the wafer support, and the air pressure in the second sealed space is reduced to the first sealed space. The pressure is applied to the front surface side of the semiconductor wafer by the air pressure generated by the pressure difference and is perpendicular to the surface of the semiconductor wafer provided above the adhesive tape. A control step of pressing and sticking the adhesive tape into the recess on the back surface of the semiconductor wafer by a sticking member that moves in a direction;
Including
In the wafer placing step, the semiconductor wafer is placed so that a groove provided in the wafer support table and a central part on the front surface side of the semiconductor wafer face each other, and the wafer support table A tape attaching method, comprising: supporting at least a part of an outer peripheral end portion thicker than a central portion of a semiconductor wafer. The tape sticking method according to claim 9 , wherein the sticking member is made of an elastic body. The tape sticking method according to claim 9 or 10 , wherein the sticking member has a circular planar shape having a diameter wider than the diameter of the semiconductor wafer. The tape sticking method according to any one of claims 9 to 11 , wherein the sticking member has a cross-sectional shape that gradually increases in thickness from an outer peripheral part toward a central part. In the holding step, the adhesive tape is held with the adhesive side down,
In the said control process, the adhesive surface of the said adhesive tape is pressed on the back surface side of the said semiconductor wafer with the said adhesive member, The tape sticking method as described in any one of Claims 9-12 characterized by the above-mentioned. 14. The control process according to claim 9 , wherein pressure is applied to a central portion on a front surface side of the semiconductor wafer having a surface element structure formed in a central portion of the front surface. The tape application method described in 1. In the control step, the sticking member is lowered vertically so that a pressure substantially equal to the pressure applied to the central portion of the front side of the semiconductor wafer is applied to the back side of the semiconductor wafer. The tape sticking method according to claim 14 , characterized in that it is characterized in that: In the said pressure reduction process, the said 1st sealed space is made into a vacuum or a pressure-reduced state, The tape sticking method as described in any one of Claims 9-15 characterized by the above-mentioned.

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