JP2017037993A - Semiconductor wafer holder, semiconductor wafer grinding device, and semiconductor wafer grinding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To grind a semiconductor wafer with high quality.SOLUTION: A wafer holding part 1 includes a vacuum chuck 11 and a semiconductor wafer holder 12. The semiconductor wafer holder 12 holds a semiconductor wafer W when a ground surface Wa of the semiconductor wafer W is ground. The semiconductor wafer holder 12 includes a carrier 121 and a suction member 122. The carrier 121 is formed into a disk shape by a material (for example, carbon fiber) having higher hardness and higher strength than the semiconductor wafer W. One side surface (an upper surface 121a) of the carrier 121 is suctioned by a chuck surface 113a of the vacuum chuck 11, and the other side surface (a lower surface) supports the suction member 122. The suction member 122 is formed into a disk shape by a material having lower hardness than the semiconductor wafer W. One side surface (an upper surface) of the suction member 122 is supported by the carrier 121, and the other side surface (a lower surface) supports the semiconductor wafer W.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a semiconductor wafer holder, a semiconductor wafer grinding apparatus, and a semiconductor wafer grinding method.

  Various semiconductor wafer holders for fixing a semiconductor wafer to a vacuum chuck are known. For example, a chucking method for holding a semiconductor wafer by interposing a liquid on the chuck surface of a vacuum chuck body is disclosed (see Patent Document 1). In this chucking method, the ring-shaped member is disposed so as to cover the outer peripheral edge of the semiconductor wafer.

  According to Patent Document 1, according to the chucking method, since the periphery of the semiconductor wafer is held by the ring-shaped member, the semiconductor wafer can be securely held, and the semiconductor wafer can be surface-processed with high quality. It is described.

JP-A-10-277929

  However, in the above chucking method, the semiconductor wafer may be damaged when the surface to be ground of the semiconductor wafer is ground. When grinding the surface to be ground of the semiconductor wafer, the vacuum chuck body presses the semiconductor wafer against the grindstone. Further, for example, foreign matter such as semiconductor wafer fragments and abrasive grains may enter between the chuck surface of the vacuum chuck body and the semiconductor wafer. In such a case, the foreign matter presses the surface of the semiconductor wafer opposite to the surface to be ground to form a recess.

  When the grinding of the surface to be ground is completed, the semiconductor wafer is removed from the chuck surface of the vacuum chuck body. At this time, the recess formed on the surface of the semiconductor wafer opposite to the surface to be ground is elastically recovered. As a result, a recess is formed in the surface to be ground of the semiconductor wafer at a position facing the recess. This phenomenon is called “transcription”. That is, when foreign matter enters between the chuck surface of the vacuum chuck body and the semiconductor wafer, a recess is formed on the surface to be ground by transfer. Therefore, the semiconductor wafer cannot be ground with high quality.

  The present invention has been made in view of the above problems, and an object thereof is to provide a semiconductor wafer holder, a semiconductor wafer grinding apparatus, and a semiconductor wafer grinding method capable of grinding a semiconductor wafer with high quality.

  A semiconductor wafer holder according to a first aspect of the present invention is a semiconductor wafer holder that holds the semiconductor wafer when grinding a surface to be ground of the semiconductor wafer, and includes a carrier and a suction member. The carrier is formed in a plate shape with a material having higher hardness and higher strength than the semiconductor wafer. Further, one surface of the carrier is adsorbed on the chuck surface of the vacuum chuck, and the other surface supports the adsorbing member. The adsorbing member is formed in a plate shape with a material whose hardness is lower than that of the semiconductor wafer. In addition, one surface of the adsorption member is supported by the carrier, and the other surface supports the semiconductor wafer.

  A semiconductor wafer holder according to a second aspect of the present invention is the semiconductor wafer holder according to the first aspect, wherein the carrier has a fixed wall erected around the suction member.

  A semiconductor wafer holder according to a third aspect of the present invention is the semiconductor wafer holder according to the first aspect, and is provided on an outer peripheral portion of the adsorption member and has a fixing wall for fixing the semiconductor wafer. .

  A semiconductor wafer holder according to a fourth aspect of the present invention is the semiconductor wafer holder according to any one of the first to third aspects, wherein the one surface of the carrier has a rough surface. The degree is 1 μmRa or less.

  A semiconductor wafer holder according to a fifth aspect of the present invention is the semiconductor wafer holder according to any one of the first to fourth aspects, wherein the one side surface of the carrier is The flatness per length corresponding to the diameter of the semiconductor wafer is formed below the flatness required for the semiconductor wafer.

  A semiconductor wafer holder according to a sixth aspect of the present invention is the semiconductor wafer holder according to any one of the first to fifth aspects, and the material of the carrier is carbon fiber.

  A semiconductor wafer holder according to a seventh aspect of the present invention is the semiconductor wafer holder according to any one of the first to sixth aspects, wherein the adsorption member is made of a plastic material. Is done.

  A semiconductor wafer holder according to an eighth aspect of the present invention is the semiconductor wafer holder according to the seventh aspect, wherein the adsorption member is formed by compressing a material containing felt and epoxy resin. .

  A semiconductor wafer grinding apparatus according to the present invention is a semiconductor wafer grinding apparatus for grinding the surface to be ground of the semiconductor wafer, wherein the semiconductor wafer holder according to any one of the first to eighth aspects, The vacuum chuck and a grinding part are provided. The vacuum chuck has the chuck surface for sucking the semiconductor wafer holder. The grinding part has a grindstone for grinding the surface to be ground of the semiconductor wafer.

  A semiconductor wafer grinding method according to the present invention is a semiconductor wafer grinding method for grinding the surface to be ground of the semiconductor wafer, wherein the semiconductor wafer holder according to any one of the first to eighth embodiments is used. The semiconductor wafer holder holds the semiconductor wafer, and the surface to be ground is ground with a grindstone.

  According to the semiconductor wafer holder, the semiconductor wafer grinding apparatus, and the semiconductor wafer grinding method of the present invention, the semiconductor wafer can be ground with high quality.

It is a flowchart which shows the manufacturing method of a semiconductor wafer. 1 is a side view of a semiconductor wafer grinding apparatus according to an embodiment of the present invention. FIG. 3 is a side view of the vacuum chuck shown in FIG. 2 and the semiconductor wafer holder according to the first embodiment. FIG. 4 is an exploded view of the semiconductor wafer holder according to the first embodiment shown in FIG. 3. It is a side view of the semiconductor wafer holder which concerns on the vacuum chuck shown in FIG. 2, and 2nd Embodiment. FIG. 6 is an exploded view of a semiconductor wafer holder according to the second embodiment shown in FIG. 5.

  Embodiments of the present invention will be described below with reference to the drawings (FIGS. 1 to 6). In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof is not repeated. First, a method for manufacturing a semiconductor wafer will be described with reference to FIG. FIG. 1 is a flowchart showing a method for manufacturing a semiconductor wafer.

  First, in step S10, a cylindrical ingot is cut to obtain a disk-shaped semiconductor wafer. Next, in step S20, the peripheral portion of the semiconductor wafer is chamfered in order to suppress cracking and chipping of the peripheral portion of the semiconductor wafer. Next, in step S30, the surface to be ground opposite to the main surface of the semiconductor wafer is lapped so that the semiconductor wafer has a predetermined thickness. Next, in step S40, the semiconductor wafer is etched to remove processing distortion caused by lapping. In step S50, the surface to be ground of the semiconductor wafer is polished into a mirror surface. Finally, in step S60, the semiconductor wafer is washed with a chemical solution to remove impurities such as particles.

  The semiconductor wafer grinding apparatus 100 of this embodiment is used, for example, in at least one of the lapping process in step S30 and the polishing in step S50 in FIG. However, even when used in the lapping process, the lapping method is not used. In addition, the lapping method is “by the carrier on which the wafer is set revolves between the rotating upper and lower lap surface plates, and the wafer and the lap surface plate are rubbed together through an abrasive containing abrasive grains. It means “mechanical polishing method”. In other words, the semiconductor wafer grinding apparatus 100 of this embodiment grinds the surface Wa of the semiconductor wafer W with the grindstone 21 (see FIG. 2). Further, when the grinding ability of the semiconductor wafer grinding apparatus 100 is high and the surface Wa of the semiconductor wafer W can be beautifully ground, steps S30 and S40 in FIG. 1 can be omitted. is there.

<First Embodiment>
Next, the configuration of the semiconductor wafer grinding apparatus 100 according to the embodiment of the present invention will be described with reference to FIG. FIG. 2 is a side view of the semiconductor wafer grinding apparatus 100 according to the embodiment of the present invention.

  As shown in FIG. 2, the semiconductor wafer grinding apparatus 100 includes two wafer holding units 1 and one grinding wheel 2. The two wafer holders 1 have the same configuration.

  The wafer holding unit 1 includes a vacuum chuck 11, a semiconductor wafer holder 12, and a first driving unit 15. The vacuum chuck 11 holds the semiconductor wafer holder 12. Further, the vacuum chuck 11 moves up and down integrally with the semiconductor wafer holder 12. The first drive unit 15 includes a motor and the like, and drives the vacuum chuck 11 to move up and down and rotate. The first drive unit 15 drives the vacuum chuck 11 to rotate about the central axis 13 of the vacuum chuck 11. In addition, the first drive unit 15 drives the vacuum chuck 11 to rotate counterclockwise as viewed from above, for example, as indicated by an arrow R1.

  The first drive unit 15 raises and lowers the vacuum chuck 11 between an upper limit position and a lower limit position. When the vacuum chuck 11 is retracted, the first drive unit 15 moves the vacuum chuck 11 to the upper limit position. Therefore, the upper limit position may be described as the retracted position. Further, when grinding the semiconductor wafer W, the first drive unit 15 moves the vacuum chuck 11 to the lower limit position. Therefore, the lower limit position may be described as a grinding position. Further, when grinding the semiconductor wafer W, the first driving unit 15 presses the semiconductor wafer holder 12 and the semiconductor wafer W held by the vacuum chuck 11 toward the grinding wheel 2. In other words, the semiconductor wafer W is pressed toward the grinding wheel 2 by the vacuum chuck 11.

  The grinding wheel 2 includes a grindstone 21, a holder 22, a support shaft 23, and a second drive unit 25. The grindstone 21 is disposed so as to face the ground surface Wa (the lower surface in FIG. 2) of the semiconductor wafer W. Further, the grindstone 21 is brought into sliding contact with the surface to be ground Wa of the semiconductor wafer W to grind the surface Wa to be ground of the semiconductor wafer W. The grindstone 21 is formed in an annular shape. The grindstone 21 is fixed to the holder 22.

  The holder 22 supports the grindstone 21. The holder 22 is formed in a disk shape. The support shaft 23 rotatably supports the holder 22. The support shaft 23 is fixed vertically to the center of the surface of the holder 31 opposite to the grindstone 21. The support shaft 23 rotationally drives the holder 22 and the grindstone 21 around the center axis 24 of the support shaft 23. For example, as shown by an arrow R2, the second drive unit 25 drives the grinding wheel 2 to rotate counterclockwise when viewed from above.

  A central axis 24 of the support shaft 23 is arranged in parallel with the central axis 13 of the vacuum chuck 11. Further, the center shaft 24 of the support shaft 23 is located at the center of the center shaft 13 of the two vacuum chucks 11. In other words, the central axes 13 of the two vacuum chucks 11 are arranged at positions that are line-symmetric with respect to the central axis 24 of the support shaft 23.

  Next, the configuration of the vacuum chuck 11 and the semiconductor wafer holder 12 will be described with reference to FIG. FIG. 3 is a side view of the vacuum chuck 11 and the semiconductor wafer holder 12 according to the first embodiment. The vacuum chuck 11 includes a chuck main body 111, a suction passage 112, a suction unit 113, and a suction source 114. The chuck body 111 has a suction portion 113 disposed at the lower end position. The chuck body 111 has a suction passage 112 formed therein.

  The suction passage 112 transmits the negative pressure generated by the suction source 114 to the suction unit 113. The suction source 114 includes, for example, a vacuum pump, and makes the atmospheric pressure in the suction passage 112 equal to or lower than a predetermined atmospheric pressure. For example, the differential atmospheric pressure is 70 kPa with respect to the atmospheric pressure. The suction part 113 is formed in a disk shape by a porous member. For example, the suction part 113 is made of porous ceramics. That is, pores (porous) are formed in the suction part 113. The vacuum chuck 11 is a so-called “porous chuck”. The pore diameter is, for example, 40 μm to 60 μm.

  In the present embodiment, a mode in which the vacuum chuck 11 is a porous chuck will be described, but the present invention is not limited to this. For example, the suction part 113 may be ceramics in which fine holes are formed. Specifically, for example, the suction section 113 may be formed with a plurality of cylindrical holes that are inserted between the suction passage 112 and the upper surface 121a of the carrier 121. The diameter of the hole is, for example, 0.5 mm, and the number of holes is, for example, 100.

  Further, the semiconductor wafer holder 12 is fixed to the lower surface of the suction part 113. Specifically, the negative pressure applied to the upper surface of the suction unit 113 is transmitted to the lower surface (chuck surface 113 a) of the suction unit 113 through the pores formed in the suction unit 113. That is, the semiconductor wafer holder 12 disposed on the chuck surface 113 a of the suction unit 113 is attracted to the chuck surface 113 a of the suction unit 113 by the negative pressure applied to the upper surface of the suction unit 113.

  The semiconductor wafer holder 12 includes a carrier 121 and a suction member 122. The carrier 121 is formed in a disk shape with a material having higher hardness and higher strength than the semiconductor wafer W. For example, the material of the carrier 121 is carbon fiber. The carrier 121 has one surface (upper surface 121 a in FIG. 3) adsorbed to the chuck surface 113 a of the vacuum chuck 11. Further, the other surface (the lower surface in FIG. 3) of the carrier 121 supports the suction member 122.

  The outer diameter of the suction part 113 is configured to be larger than the outer diameter of the carrier 121 to be sucked and held or equal to the outer diameter of the carrier 121. In FIG. 3, the outer diameter of the suction part 113 is slightly larger than the outer diameter of the carrier 121. When the outer diameter of the suction part 113 is larger than the outer diameter of the carrier 121, the difference is, for example, 2 mm or less. The larger the difference between the outer diameter of the suction part 113 and the carrier 121, the larger the area of the suction part 113 located outside the outer edge of the carrier 121. Therefore, the air flows into the suction passage 112 from the suction portion 113 located outside the outer edge of the carrier 121. Therefore, the degree of vacuum in the suction passage 112 decreases. In other words, in order to increase the degree of vacuum in the suction passage 112, it is preferable to reduce the difference between the outer diameter of the suction portion 113 and the carrier 121.

  The upper surface 121a of the carrier 121 is formed with low roughness. For example, the upper surface 121a of the carrier 121 has a roughness of 1 μmRa or less. The carrier 121 is formed with high flatness. For example, the carrier 121 is formed so that the flatness per length corresponding to the diameter of the semiconductor wafer W is less than the flatness required for the semiconductor wafer W. Specifically, the carrier 121 is formed to have a flatness of 1 μm or less per 150 mm length, for example. The “flatness” of the carrier 121 is the maximum value of the thickness difference of the carrier 121. In other words, the “flatness” of the carrier 121 is the difference between the maximum value and the minimum value of the thickness of the carrier 121. Further, the “flatness” required for the semiconductor wafer W is defined by, for example, GBIR (Global backside ideal range).

  The carrier 121 has a fixed wall 121 b that stands up around the suction member 122. The fixed wall 121b is formed in an annular shape. The fixed wall 121b restricts the movement of the semiconductor wafer W in the horizontal direction. Further, the diameter of the inner peripheral surface of the fixed wall 121b is formed substantially the same as the diameter of the adsorption member 122. That is, the adsorption member 122 fits inside the fixed wall 121b without a gap. Further, the diameter of the outer peripheral surface of the fixed wall 121 b is formed substantially the same as the diameter of the carrier 121. The height HW of the fixed wall 121b is larger than the thickness TB of the adsorption member 122.

  One surface (upper surface in FIG. 3) of the adsorption member 122 is supported by the carrier 121, and the other surface (lower surface in FIG. 3) supports the semiconductor wafer W. In other words, the suction member 122 is housed inside the fixed wall 121 b of the carrier 121 and is disposed between the carrier 121 and the semiconductor wafer W.

  The suction member 122 is made of a material having a lower hardness than the semiconductor wafer W and is formed in a disk shape. Further, the adsorption member 122 is formed of a plastic material. That is, the adsorption member 122 is formed so as to be deformable. For example, the adsorbing member 122 is formed by compressing a material including felt and epoxy resin. Specifically, for example, the adsorption member 122 is formed by compressing felt and epoxy resin. The diameter of the suction member 122 is substantially the same as the diameter of the semiconductor wafer W. Further, the sum of the thickness TB of the adsorption member 122 and the thickness TW of the semiconductor wafer W is larger than the height HW of the fixed wall 121b. In other words, the semiconductor wafer W is held by the fixed wall 121b and the suction member 122 in a state where a part of the semiconductor wafer W protrudes from the fixed wall 121b.

  Further, the adsorption member 122 is formed in a shape that allows the semiconductor wafer W to be easily removed. Specifically, for example, the suction member 122 is formed so that the diameter of the suction member 122 is shorter than the diameter of the semiconductor wafer W by a predetermined length (for example, 10 mm). In this embodiment, since the outer edge portion of the semiconductor wafer W protrudes from the adsorption member 122, the semiconductor wafer W can be easily detached from the adsorption member 122.

  Next, a procedure for grinding the semiconductor wafer W by the semiconductor wafer grinding apparatus 100 will be described with reference to FIG. 4 is an exploded view of the semiconductor wafer holder 12 shown in FIG. In a state before starting grinding, the vacuum chuck 11 is in the retracted position (upper limit position). The adsorption member 122 is mounted on the carrier 121 in advance. Specifically, the adsorbing member 122 is inserted inside the fixed wall 121 b of the carrier 121 until a liquid such as water adheres to the upper surface of the adsorbing member 122 and comes into contact with the lower surface of the carrier 121. As a result, the upper surface of the adsorption member 122 and the lower surface of the carrier 121 are fixed with a liquid interposed therebetween.

  First, suction of the vacuum chuck 11 is started. Next, a liquid such as water is attached to the upper surface 121 a of the carrier 121, and the carrier 121 is adsorbed on the chuck surface 113 a of the vacuum chuck 11. In this way, the semiconductor wafer holder 12 is mounted on the vacuum chuck 11.

  Next, a liquid such as water is adhered to the upper surface of the semiconductor wafer W, and the semiconductor wafer W is inserted inside the fixed wall 121b of the carrier 121 until it contacts the lower surface of the adsorption member 122. The upper surface of the semiconductor wafer W and the lower surface of the adsorption member 122 are fixed with a liquid interposed therebetween. In this way, the semiconductor wafer W is set on the semiconductor wafer holder 12.

  Next, the two vacuum chucks 11 and the grinding wheel 2 start to rotate. Then, the two vacuum chucks 11 are lowered to the grinding position (lower limit position), and the surface Wa (the lower surface) to be ground of the semiconductor wafer W is ground. When the grinding is completed, the two vacuum chucks 11 are raised to the retracted position (upper limit position). Then, the rotation of the two vacuum chucks 11 and the grinding wheel 2 is stopped.

  As described with reference to FIGS. 2 to 4, the carrier 121 has one surface (upper surface 121 a) adsorbed to the chuck surface 113 a of the vacuum chuck 11 and the other surface (lower surface) is an adsorbing member. 122 is supported. One surface (upper surface) of the suction member 122 is supported by the carrier 121, and the other surface (lower surface) supports the semiconductor wafer W. The carrier 121 is formed in a disk shape with a material having higher hardness and strength than the semiconductor wafer W. The adsorbing member 122 is formed in a disk shape with a material whose hardness is lower than that of the semiconductor wafer W.

  Therefore, when a foreign matter such as a ground piece of the semiconductor wafer W enters between the suction member 122 and the semiconductor wafer W, the suction member 122 is deformed according to the foreign matter, so that the semiconductor wafer W is damaged. This can be suppressed. Therefore, the semiconductor wafer W can be ground with high quality.

  Further, since the adsorbing member 122 has plasticity, the semiconductor wafer W can be easily fixed to the adsorbing member 122 by interposing a liquid such as water between the adsorbing member 122 and the semiconductor wafer W. This is because the suction member 122 is deformed along the surface of the semiconductor wafer W on the suction member 122 side.

  In addition, since the carrier 121 has a fixed wall 121b erected around the suction member 122, the movement of the semiconductor wafer W in the horizontal direction is restricted by the fixed wall 121b. Therefore, the semiconductor wafer W can be firmly fixed to the chuck surface 113a of the vacuum chuck 11.

  Furthermore, one surface (upper surface 121a) of the carrier 121 is attracted to the chuck surface 113a of the vacuum chuck 11 and has a roughness of 1 μmRa or less. Therefore, the carrier 121 can be firmly fixed to the chuck surface 113a of the vacuum chuck 11 by interposing a liquid such as water.

  Further, the carrier 121 is formed so that the flatness per length corresponding to the diameter of the semiconductor wafer W is equal to or lower than the flatness required for the semiconductor wafer W. Therefore, the semiconductor wafer W can be ground to the required flatness.

  The adsorbing member 122 is formed by compressing felt and epoxy resin. Therefore, the adsorption member 122 having plasticity and lower hardness than the semiconductor wafer W can be formed.

  Furthermore, the material of the carrier 121 is carbon fiber. Therefore, the carrier 121 having higher hardness and higher strength than the semiconductor wafer W can be formed.

  Further, the semiconductor wafer holder 12 is attracted to the chuck surface 113 a of the vacuum chuck 11, and the surface to be ground Wa of the semiconductor wafer W is ground with the semiconductor wafer holder 12 holding the semiconductor wafer W. Therefore, when a foreign matter such as a ground piece of the semiconductor wafer W enters between the suction member 122 and the semiconductor wafer W, the suction member 122 is deformed according to the foreign matter, so that the semiconductor wafer W is damaged. This can be suppressed. Therefore, the semiconductor wafer W can be ground with high quality.

  As described with reference to FIG. 4, the upper surface 121 a of the carrier 121 is adsorbed to the chuck surface 113 a of the vacuum chuck 11 through a liquid such as water. Further, the upper surface of the adsorption member 122 and the lower surface of the carrier 121 are fixed with a liquid such as water interposed therebetween. Furthermore, the upper surface of the semiconductor wafer W and the lower surface of the adsorption member 122 are fixed with a liquid such as water interposed. Therefore, the semiconductor wafer holder 12 can be easily attracted to the vacuum chuck 11. Further, the semiconductor wafer W can be easily adsorbed to the semiconductor wafer holder 12. Therefore, the semiconductor wafer W can be efficiently ground by the semiconductor wafer grinding apparatus 100.

Second Embodiment
Next, with reference to FIG.5 and FIG.6, the semiconductor wafer holder 14 which concerns on 2nd Embodiment is demonstrated. FIG. 5 is a side view of the vacuum chuck 11 and the semiconductor wafer holder 14 according to the second embodiment. FIG. 6 is an exploded view of the semiconductor wafer holder 14 according to the second embodiment.

The semiconductor wafer holder 14 according to the second embodiment differs from the semiconductor wafer holder 12 according to the first embodiment mainly in the following two points.
Difference A: The carrier does not have a fixed wall.
Difference B: The fixed wall is fixed to the adsorption member.
Hereinafter, of the configuration of the semiconductor wafer holder 14, differences from the semiconductor wafer holder 12 will be mainly described.

  The semiconductor wafer holder 14 includes a carrier 141, a suction member 142, and a fixed wall 143. The carrier 141 is formed in a disk shape with a material having higher hardness and higher strength than the semiconductor wafer W. For example, the material of the carrier 141 is carbon fiber. Further, the carrier 141 has one surface (upper surface 141 a in FIG. 5) adsorbed to the chuck surface 113 a of the vacuum chuck 11. Further, the carrier 141 supports the suction member 142 on the other side surface (the lower surface in FIG. 3).

  Similar to the upper surface 121a of the carrier 121 of the first embodiment, the upper surface 141a of the carrier 141 is formed with low roughness. Further, the upper surface 141a of the carrier 141 is formed with high flatness, similar to the upper surface 121a of the carrier 121 of the first embodiment.

  One surface (upper surface in FIG. 5) of the adsorption member 142 is supported by the carrier 141, and the other surface (lower surface in FIG. 5) supports the semiconductor wafer W. The adsorbing member 142 is plastic and has a circular shape made of a material having a hardness lower than that of the semiconductor wafer W. Specifically, the suction member 142 is formed by compressing felt and an epoxy resin, similarly to the suction member 122 of the first embodiment.

  The fixed wall 143 is formed in an annular shape. The material of the fixed wall 143 is the same carbon fiber as the material of the carrier 141. One surface of the fixed wall 143 (the upper surface in FIG. 5) is supported by the adsorption member 142. The fixed wall 143 restricts the movement of the semiconductor wafer W in the horizontal direction. Further, the diameter of the outer peripheral surface of the fixed wall 143 is formed substantially the same as the diameter of the adsorption member 142. The diameter of the inner peripheral surface of the fixed wall 143 is substantially the same as the diameter of the semiconductor wafer W. The thickness T3 of the fixed wall 143 is thinner than the thickness TW of the semiconductor wafer W. In other words, the semiconductor wafer W is held by the fixed wall 143 and the suction member 142 in a state where a part of the semiconductor wafer W protrudes from the fixed wall 143.

  Next, a procedure for grinding the semiconductor wafer W by the semiconductor wafer grinding apparatus 100 will be described with reference to FIG. In a state before starting grinding, the vacuum chuck 11 is in the retracted position (upper limit position). The adsorption member 142 and the fixed wall 143 are mounted on the carrier 141 in advance. Specifically, a liquid such as water is attached to the upper surface of the adsorption member 142 and fixed to the carrier 141. The upper surface of the adsorption member 142 and the lower surface of the carrier 141 are fixed with a liquid interposed therebetween. Further, a liquid such as water is attached to the upper surface of the fixed wall 143 and fixed to the adsorption member 142. The upper surface of the fixed wall 143 and the lower surface of the adsorption member 142 are fixed with a liquid interposed therebetween. In this way, the suction member 142 and the fixed wall 143 are attached to the carrier 141.

  First, suction of the vacuum chuck 11 is started. Next, a liquid such as water is attached to the upper surface 141 a of the carrier 141 and is adsorbed on the chuck surface 113 a of the vacuum chuck 11. In this way, the semiconductor wafer holder 14 is set on the vacuum chuck 11.

  Next, a liquid such as water is adhered to the upper surface of the semiconductor wafer W, and the semiconductor wafer W is inserted inside the fixed wall 143 until it contacts the lower surface of the adsorption member 142. The upper surface of the semiconductor wafer W and the lower surface of the adsorption member 142 are fixed with a liquid interposed therebetween. In this way, the semiconductor wafer W is set on the semiconductor wafer holder 14.

  Next, the two vacuum chucks 11 and the grinding wheel 2 start to rotate. Then, the two vacuum chucks 11 are lowered to the grinding position (lower limit position), and the surface Wa (the lower surface) to be ground of the semiconductor wafer W is ground. When the grinding is completed, the two vacuum chucks 11 are raised to the retracted position (upper limit position). Then, the rotation of the two vacuum chucks 11 and the grinding wheel 2 is stopped.

  As described with reference to FIGS. 5 and 6, the carrier 141 has one surface (upper surface 141a) adsorbed to the chuck surface 113a of the vacuum chuck 11, and the other surface (lower surface) is an adsorbing member. 142 is supported. One surface (upper surface) of the suction member 142 is supported by the carrier 141, and the other surface (lower surface) supports the semiconductor wafer W. The carrier 141 is formed in a disk shape with a material having higher hardness and higher strength than the semiconductor wafer W. The suction member 142 is formed in a disk shape with a material having a lower hardness than the semiconductor wafer W.

  Therefore, when a foreign matter such as a ground piece of the semiconductor wafer W enters between the suction member 142 and the semiconductor wafer W, the suction member 142 is deformed according to the foreign matter, so that the semiconductor wafer W is damaged. This can be suppressed. Therefore, the semiconductor wafer W can be ground with high quality.

  Further, the semiconductor wafer holder 14 has a fixed wall 143. The fixed wall 143 is disposed on the outer periphery of the adsorption member 142 and fixes the semiconductor wafer W. Therefore, the movement of the semiconductor wafer in the horizontal direction is restricted by the fixed wall 143. Therefore, the semiconductor wafer W can be firmly fixed.

  The embodiments of the present invention have been described above with reference to the drawings. However, the present invention is not limited to the above-described embodiment, and can be implemented in various modes without departing from the gist thereof (for example, (1) to (3) shown below). For ease of understanding, the drawings schematically show each component as a main component, and the thickness, length, number, etc. of each component shown in the drawings are different from the actual for convenience of drawing. There is a case. Moreover, the shape, dimension, etc. of each component shown by said embodiment are an example, Comprising: It does not specifically limit, A various change is possible in the range which does not deviate substantially from the structure of this invention.

  (1) Although the semiconductor wafer grinding apparatus 100 has been described with reference to FIG. 2 as having two wafer holders 1, the present invention is not limited to this. For example, the semiconductor wafer grinding apparatus 100 may include three or more wafer holding units 1. As the number of wafer holders 1 increases, the grinding efficiency can be increased. Further, for example, the semiconductor wafer grinding apparatus 100 may include one wafer holding unit 1.

  (2) Although the embodiment in which the wafer holding unit 1 and the grinding wheel 2 rotate in the same direction has been described with reference to FIG. 2, the present invention is not limited to this. For example, the grinding wheel 2 may be rotated in the direction opposite to the wafer holding unit 1.

  (3) Although the embodiment in which the wafer holding unit 1 holds one semiconductor wafer W has been described with reference to FIG. 3, the present invention is not limited to this. For example, the wafer holding unit 1 may hold two or more semiconductor wafers W.

  The present invention can be used in the fields of a semiconductor wafer holder, a semiconductor wafer grinding apparatus, and a semiconductor wafer grinding method.

DESCRIPTION OF SYMBOLS 100 Semiconductor wafer grinding apparatus 1 Wafer holding part 11 Vacuum chuck 111 Chuck main body 112 Suction passage 113 Suction part 113a Chuck surface 114 Suction source 12 Semiconductor wafer holder 121 Carrier 121b Fixed wall 122 Adsorption member 13 Central axis 14 Semiconductor wafer holder 141 Carrier 142 Adsorption member 143 Fixed wall 15 1st drive part 2 Grinding wheel 21 Grinding wheel 22 Holder 23 Support shaft 24 Center axis 25 2nd drive part W Semiconductor wafer Wa Surface to be ground

Claims (10)

A semiconductor wafer holder for holding the semiconductor wafer when grinding a surface to be ground of the semiconductor wafer,
A carrier formed in a plate shape with a material having higher hardness and strength than the semiconductor wafer;
An adsorption member formed in a plate shape with a material having a lower hardness than the semiconductor wafer,
The carrier has one surface adsorbed on the chuck surface of the vacuum chuck, and the other surface supports the adsorbing member,
One surface of the adsorption member is supported by the carrier, and the other surface is a semiconductor wafer holder that supports the semiconductor wafer.   The semiconductor wafer holder according to claim 1, wherein the carrier has a fixed wall erected around the adsorption member.   The semiconductor wafer holder according to claim 1, wherein the semiconductor wafer holder has a fixed wall that is disposed on an outer peripheral portion of the adsorption member and fixes the semiconductor wafer.   4. The semiconductor wafer holder according to claim 1, wherein the surface of the one side of the carrier has a roughness of 1 μmRa or less. 5.   5. The carrier according to claim 1, wherein a flatness per length corresponding to a diameter of the semiconductor wafer is formed to be equal to or less than a flatness required for the semiconductor wafer. Semiconductor wafer holder.   The semiconductor wafer holder according to claim 1, wherein the material of the carrier is carbon fiber.   The semiconductor wafer holder according to claim 1, wherein the adsorption member is formed of a plastic material.   The semiconductor wafer holder according to claim 7, wherein the adsorption member is formed by compressing a material including felt and epoxy resin. A semiconductor wafer grinding apparatus for grinding the ground surface of the semiconductor wafer,
The semiconductor wafer holder according to any one of claims 1 to 8,
The vacuum chuck having the chuck surface for adsorbing the semiconductor wafer holder;
A semiconductor wafer grinding apparatus comprising: a grinding unit having a grindstone for grinding the ground surface of the semiconductor wafer. A semiconductor wafer grinding method for grinding the ground surface of the semiconductor wafer,
The semiconductor wafer holder according to any one of claims 1 to 8 is adsorbed to a chuck surface of the vacuum chuck,
A semiconductor wafer grinding method, wherein the semiconductor wafer holder holds the semiconductor wafer, and the ground surface is ground with a grindstone.

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