JP6280403B2 - Polishing substrate manufacturing method - Google Patents

Description

  The present invention relates to a method for manufacturing a polishing substrate.

  Conventionally, as a substrate polishing method, a substrate is adhered to a substrate carrier, and the surface of the substrate is brought into contact with a polishing surface plate in that state, and polishing is performed by rotating the polishing surface plate and the substrate carrier while supplying an abrasive. The method is known. In addition, it is known that the substrate carrier and the substrate are bonded via an adhesive such as wax. For example, Patent Document 1 describes that a substrate is heated to 50 to 60 ° C. and bonded to a substrate carrier through wax. It also describes that after polishing, the substrate carrier is heated to 60 to 80 ° C. to melt wax, and the substrate is peeled off from the substrate carrier.

Japanese Utility Model Publication No. 58-129658

  However, in the method described in Patent Document 1, since the substrate is heated after polishing, the substrate may be damaged at the time of peeling from the substrate carrier depending on the thickness of the substrate after polishing and the thermal expansion coefficient of the substrate.

  The present invention has been made in order to solve such a problem, and has as its main object to further suppress damage to the polishing substrate when it is peeled off from the substrate carrier.

The method for producing a polishing substrate of the present invention comprises:
(A) a step of preparing a substrate and a substrate carrier having a carrier-side bonding surface for bonding the substrate;
(B) a step of bonding the substrate to the carrier-side bonding surface via an adhesive to form an bonded body;
(C) polishing the surface of the substrate opposite to the bonding surface with the substrate carrier to form a polished substrate;
(D) peeling the polishing substrate from the substrate carrier in a state where the polishing substrate is cooled to −15 ° C. or more and 0 ° C. or less;
Is included.

  In the method for producing a polishing substrate of the present invention, the polishing substrate is cooled to 0 ° C. or lower when the polishing substrate is peeled from the adhesive body between the polishing substrate and the substrate carrier. Therefore, since the adhesive is easily peeled off by cooling, the polishing substrate can be peeled off from the substrate carrier using, for example, a linear member or a spatula member without melting the adhesive by heating. And since the temperature of the grinding | polishing board | substrate at the time of peeling is made into -15 degreeC or more, it can suppress more that a grinding | polishing board | substrate is damaged by the thermal stress by cooling. By these, compared with the case where an adhesive agent is heated at the time of peeling, the failure | damage of the grinding | polishing board | substrate at the time of peeling from a substrate carrier can be suppressed more.

  In the method for producing a polishing substrate of the present invention, in the step (a), the substrate having an orientation flat is prepared, and in the step (b), both ends of the orientation flat protrude from the carrier-side adhesive surface. The substrate and the substrate carrier are bonded so as to provide a protruding surface and a carrier-side protruding surface in which a part of the carrier-side adhesive surface protrudes from the orientation flat. In the step (d), the carrier side A linear member is stretched across the protruding surface and on both sides of the substrate so as to pass through the protruding surface side of the substrate, and the polishing substrate is separated from the substrate carrier by pulling both sides of the linear member. Also good. In this way, when the adhesive body is viewed in the direction perpendicular to the carrier-side adhesive surface and seen from the substrate side, the carrier-side protruding surface is positioned at the first and second contact points adjacent to the substrate-side protruding surface on both sides thereof. The force from the linear member can be applied intensively to the two adhesives. Thereby, for example, it can suppress more that unnecessary force is added to the edge part etc. of a polish substrate, and can control damage of a polish substrate at the time of exfoliation more.

  In the method for producing a polishing substrate of the present invention, in the step (a), the substrate carrier in which an outer peripheral edge of the carrier-side adhesive surface is chamfered may be prepared. In this case, when the linear member is pulled, the linear member can easily enter between the polishing substrate and the substrate carrier, and thus the polishing substrate can be more easily peeled off.

  In the method for producing a polishing substrate of the present invention, in the step (d), both sides of the linear member are pulled in a direction parallel to the carrier-side adhesive surface or in an oblique direction inclined from the parallel direction to the substrate carrier side. The polishing substrate may be peeled from the substrate carrier by pulling. In this case, for example, damage to the polishing substrate can be further suppressed as compared with a case where the linear member is pulled in an oblique direction inclined from the parallel direction toward the polishing substrate.

  In the method for producing a polishing substrate of the present invention, in the step (a), the substrate obtained by bonding a piezoelectric substrate and a support substrate is prepared, and in the step (b), the support substrate side of the substrate is placed on the support substrate side. In the step (c), the surface of the piezoelectric substrate may be polished in the step (c) by bonding to a carrier-side bonding surface. In this case, in the step (c), the polishing may be performed until the thickness of the piezoelectric substrate becomes 0.1 μm or more and 40 μm or less. When the thickness of the piezoelectric substrate is 40 μm or less, the piezoelectric substrate is easily damaged at the time of peeling from the substrate carrier.

1 is a perspective view of a substrate carrier 10. FIG. The perspective view of the bonding board | substrate 30. FIG. Explanatory drawing of the adhesive body 40. FIG. FIG. 3 is an explanatory view showing a state of polishing the bonded substrate stack 30. Explanatory drawing which shows a mode that the composite substrate 20 is peeled using the linear member 59. FIG. Explanatory drawing which shows the state of the composite substrate 20 and the board | substrate carrier 10 after peeling. Explanatory drawing of the board | substrate carrier 210 of a modification. Explanatory drawing of the board | substrate carrier 310 of a modification.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of a substrate carrier 10 which is an embodiment of the substrate carrier of the present invention.

  The substrate carrier 10 includes a disk-shaped main body 12 and a shaft 14 provided at the center of the lower surface of the main body 12. The shaft 14 can be rotated by a drive motor (not shown). The substrate carrier 10 has a chamfered portion 16 by chamfering the outer peripheral edge of the upper surface (see an enlarged portion in FIG. 1). The chamfered portion 16 is formed in a ring shape so as to go around the outer periphery of the upper surface of the substrate carrier 10. Note that the chamfered portion 16 may be formed by C chamfering or may be formed by R chamfering. In the present embodiment, the chamfered portion 16 is formed by C chamfering cut at a 45 ° surface. A portion of the upper surface of the substrate carrier 10 other than the chamfered portion 16 is a circular adhesive surface 13. As a material of the substrate carrier 10, for example, a ceramic material such as alumina is generally used.

  Next, a process for manufacturing a polishing substrate will be described.

  First, as step (a), a substrate to be polished and the substrate carrier 10 described above are prepared. FIG. 2 is a perspective view of a bonded substrate 30 that is a substrate to be polished. The bonded substrate 30 is obtained by bonding a piezoelectric substrate 32 and a support substrate 24.

  The piezoelectric substrate 32 is a substantially disk-shaped substrate (wafer) having an orientation flat (OF) 33. The material of the piezoelectric substrate 32 is not particularly limited. For example, lithium tantalate (LT), lithium niobate (LN), lithium niobate-lithium tantalate solid solution single crystal, lithium borate, langasite (LGS), crystal Etc. Although the magnitude | size of the piezoelectric substrate 32 is not specifically limited, For example, a diameter is 50-150 mm and thickness is 10-80 micrometers. In this embodiment, as shown in FIG. 2, the diameter of the piezoelectric substrate 32 is smaller than that of the support substrate 24. However, the present invention is not limited to this. For example, the piezoelectric substrate 32 and the support substrate 24 have the same diameter. May be. Further, the outer peripheral edge of the piezoelectric substrate 32 may be chamfered (for example, R chamfering).

  The support substrate 24 is a substrate that supports the piezoelectric substrate 32 and is a substantially disk-shaped substrate (wafer) having an orientation flat (OF) 25. The support substrate 24 is bonded to the piezoelectric substrate 32 by direct bonding or via an organic adhesive layer. The support substrate 24 has a central axis that is the same as that of the piezoelectric substrate 32 and is bonded so that the directions of the OFs 33 and OF25 coincide with each other (the angle formed by the OF33 and OF25 is 0 ° (parallel)). The support substrate 24 is made of silicon (Si), sapphire, aluminum nitride, alumina, alkali-free glass, borosilicate glass, quartz glass, LT, LN, lithium niobate-lithium tantalate solid solution single crystal, lithium borate. , LGS, and quartz. Although the magnitude | size of the support substrate 24 is not specifically limited, For example, a diameter is 50-150 mm and thickness is 100-1000 micrometers. The outer peripheral edge of the support substrate 24 may be chamfered (for example, R chamfering).

  Such a bonded substrate 30 is manufactured, for example, as follows. First, a piezoelectric substrate 32 having a thickness of 100 to 1000 μm and a support substrate 24 having a thickness of 100 to 1000 μm are prepared, and both are bonded by direct bonding or bonded via an organic adhesive layer to produce a bonded substrate 30. . In the case of bonding by direct bonding, first, the bonding surfaces of the piezoelectric substrate 32 and the support substrate 24 are activated, and then both the substrates 32 and 24 are pressed with the bonding surfaces facing each other. The bonding surface is activated by, for example, irradiation of an ion beam of an inert gas (such as argon) to the bonding surface, or irradiation of plasma or a neutral atom beam. On the other hand, when bonding through an organic adhesive layer, for example, an epoxy resin or an acrylic resin is used as the organic adhesive layer. Subsequently, the piezoelectric substrate 32 of the bonded substrate 30 is ground with a grinder or the like to a thickness of 10 to 80 μm.

  Next, as a step (b), the bonding surface 26 (see FIG. 2), which is the surface on the support substrate side, of the bonded substrate 30 is bonded to the bonding surface 13 of the substrate carrier 10 via an adhesive. 40. FIG. 3 is an explanatory diagram of the adhesive body 40. 3 is a top view of the adhesive 40, and the lower part of FIG. 3 is a front view of the adhesive 40. The bonding is performed by, for example, applying an adhesive on the bonding surface 26 of the bonded substrate 30 by spin coating, and pressing the bonding surface 26 and the bonding surface 13 facing each other. As a result, the adhesive becomes the adhesive layer 42. Examples of the adhesive material include organic adhesives such as epoxy resins and acrylic resins, and waxes. The thickness of the adhesive layer 42 is, for example, 1 to 5 μm. When bonding, an adhesive may be applied to the bonding surface 13 instead of the bonding surface 26, or an adhesive may be applied to both the bonding surface 26 and the bonding surface 13. In addition, before applying the adhesive, the surface on which the adhesive is applied may be heated.

  In the present embodiment, in the step (b), the substrate carrier 10 and the bonded substrate 30 are bonded so that the central axis is coaxial. Here, the diameter of the bonding surface 13 of the substrate carrier 10 is set so that a part of the bonding surface 13 protrudes outward (radially outward) from a part of the OF 25 of the bonded substrate 30. The adhesion surface side with the bonded substrate 30 at the protruding portion is referred to as a carrier-side protruding surface 13a. At this time, in the bonded substrate 30 (support substrate 24), both ends (upper and lower ends in the upper part of FIG. 3) of the OF 25 protrude from the bonding surface 13, and a part of the bonding surface 26 is outside (diameter). (Outward in the direction). The adhesion surface side with the substrate carrier 10 in the protruding portion is referred to as a substrate-side protruding surface 26a. As shown in FIG. 3, the substrate-side protruding surface 26a exists over the entire outer peripheral edge of the bonding surface 26 other than a part of the OF 25 (the portion where the carrier-side protruding surface 13a exists). Further, when the adhesive 40 is seen through from the substrate (bonded substrate 30) side in a direction perpendicular to the bonding surface 13, the substrate-side protruding surface 26a, the carrier-side protruding surface 13a, and the substrate-side protruding surface 26a are adjacent in this order. Are lined up. The carrier-side protruding surface 13a and the substrate-side protruding surface 26a are adjacent to each other at first and second contacts 44a and 44b (see the enlarged portion in the upper part of FIG. 3). In the enlarged portion in the upper part of FIG. 3, the carrier-side protruding surface 13a and the substrate-side protruding portion are illustrated by hatching and filling. The surface on the substrate carrier 10 side of the substrate-side protruding portion shown in the figure is the substrate-side protruding surface 26a. Further, the chamfered portion 16 is also illustrated in the enlarged portion in the upper part of FIG. The first and second contacts 44a and 44b are in the direction perpendicular to the bonding surface 13 and seen from the substrate (bonded substrate 30) side, and the edge of the bonding surface 13 and the edge of the bonding surface 26 (here, OF25). Is the intersection of

  Subsequently, as a step (c), the surface of the piezoelectric substrate 32 which is the surface of the bonded substrate 30 opposite to the bonding surface 26 with the substrate carrier 10 is polished. Examples of polishing include lapping (rough polishing) using diamond slurry and the like, and CMP (finish polishing) using colloidal silica and the like. Since lapping and CMP can be performed in the same manner except that the abrasive is different, CMP will be described. FIG. 4 is an explanatory view showing a state of CMP of the bonded substrate board 30. CMP is performed using a polishing apparatus 50 shown in FIG. The polishing apparatus 50 includes a substrate carrier 10, a disk-shaped surface plate 52 having a diameter larger than that of the substrate carrier 10, and a pipe 58 that supplies slurry containing colloidal silica as an abrasive to the surface plate 52. . The surface plate 52 is provided with a shaft 54 at the center of the back surface, and rotates when the shaft 54 is rotationally driven by a drive motor (not shown). A polishing pad 56 such as a urethane pad is attached to the surface of the surface plate 52. The substrate carrier 10 may be attached to the polishing apparatus 50 so as to be replaceable according to the size of the substrate to be polished. Using this polishing apparatus 50, the surface plate 52 and the substrate carrier 10 are supplied while slurry is supplied from the pipe 58 to the polishing cloth 56 with the surface of the piezoelectric substrate 32 of the adhesive 40 in FIG. 4 in contact with the polishing cloth 56. Polishing while rotating the shaft. In the step (c), the piezoelectric substrate 32 is thinned to a thickness of, for example, 0.1 to 40 μm by polishing. Thereby, the bonded substrate 30 becomes the composite substrate 20 which is the bonded substrate 30 after polishing (see FIGS. 5 and 6 to be described later). In step (c), polishing may be performed a plurality of times, such as CMP after lapping.

  Subsequently, as the step (d), the composite substrate 20 is peeled from the substrate carrier 10 in a state where the composite substrate 20 is cooled to −15 ° C. or more and 0 ° C. or less. The peeling is performed using the linear member 59. FIG. 5 is an explanatory view showing a state where the composite substrate 20 is peeled off using the linear member 59. 5 is a top view of the adhesive 40, and the lower part of FIG. The thickness of the linear member 59 is, for example, 0.1 to 0.3 mm. The linear member 59 is preferably thinner than the adhesive layer 42, but may be thicker than the adhesive layer 42. As a material of the linear member 59, it has the intensity | strength of the grade which self does not cut | disconnect at the time of peeling, for example, nylon, a fluorocarbon, etc. are mentioned. At the time of peeling, first, as shown in FIG. 5, a linear member is stretched across the carrier side protruding surface 13a and on both sides so as to pass through the substrate side protruding surface 26a side. Then, from this state, both sides of the linear member 59 are pulled in the direction in which the linear member 59 is inserted between the composite substrate 20 and the substrate carrier 10 (leftward in FIG. 5). The pulling direction is such that both sides of the linear member 59 are parallel to the bonding surface 13 (left direction in FIG. 5), or an oblique direction (lower left direction in the lower stage in FIG. 5) inclined from the parallel direction to the substrate carrier 10 side. It is preferable to do. In the present embodiment, the pulling is performed in an oblique direction.

  When the linear member 59 is pulled in this manner, a force from the linear member 59 is applied intensively to the two adhesives (adhesive layer 42) located at the first and second contacts 44a and 44b. As a result, the linear member 59 separates the adhesive surface 26 of the composite substrate 20 and the adhesive surface 13 of the substrate carrier 10 from the first and second contacts 44a and 44b, and the adhesive surface 13 and the adhesive surface 26. The composite substrate 20 is peeled from the substrate carrier 10 as it passes to the opposite side of the adhesive 40 (the left end in FIG. 5). In addition, the dimension of the chamfered portion 16 of the substrate carrier 10 described above is, for example, 0.3 mm or more (C chamfering) so that the linear member 59 is easily inserted between the adhesive surface 13 and the adhesive surface 26. If it exists, it is preferable to set it as C0.3 mm or more. FIG. 6 is an explanatory view showing a state of the composite substrate 20 and the substrate carrier 10 after peeling. Although not shown in FIG. 6, when there is an adhesive (part of the adhesive layer 42) attached to the adhesive surface 26 of the composite substrate 20 after peeling, the adhesive is washed with, for example, a cleaning agent. Remove this.

  The composite substrate 20 peeled from the substrate carrier 10 is used as a piezoelectric device, an acoustic wave device, or the like through a step of forming an electrode pattern on the surface of the piezoelectric substrate 32 or a step of cutting into a chip shape by dicing, for example.

  Here, the correspondence between the components of the present embodiment and the components of the present invention will be clarified. The substrate carrier 10 of this embodiment corresponds to the substrate carrier of the present invention, the bonded substrate 30 corresponds to the substrate, the bonding surface 13 corresponds to the carrier-side bonding surface, and the bonding surface 26 corresponds to the bonding surface on the substrate side. The adhesive 40 corresponds to the adhesive, and the composite substrate 20 corresponds to the polishing substrate. OF25 corresponds to an orientation flat.

  In this embodiment described above, in the step (d) of peeling the composite substrate 20 from the substrate carrier 10, the composite substrate 20 is peeled off when the composite substrate 20 is peeled from the adhesive 40 between the composite substrate 20 and the substrate carrier 10. Cooling below 0 ° C. Therefore, since the adhesive (adhesive layer 42) is easily peeled off by cooling, the composite substrate 20 can be peeled from the substrate carrier 10 using the linear member 59 without melting the adhesive by heating. . And since the temperature of the composite substrate 20 at the time of peeling is made into -15 degreeC or more, it can suppress more that the composite substrate 20 is damaged with the thermal stress by cooling. By these, compared with the case where the adhesive (adhesive layer 42) is heated at the time of peeling, damage to the composite substrate 20 at the time of peeling from the substrate carrier 10 (for example, thermal expansion of the composite substrate 20 or the piezoelectric substrate 32 and the support substrate 24) Can be further suppressed.

  Further, by performing the above-described steps (b) and (d), the carrier-side protruding surface 13a and the substrate-side protrusions on both sides when the adhesive 40 is seen through from the substrate side in a direction perpendicular to the bonding surface 13 are obtained. The force from the linear member 59 can be applied intensively to two adhesives located at the first and second contacts 44a and 44b, which are adjacent to the surface 26a. Thereby, for example, it can suppress more that unnecessary force is added to the edge part of the composite substrate 20, etc., and can suppress the damage of the composite substrate 20 at the time of peeling more.

  In step (a), the substrate carrier 10 is prepared in which the outer peripheral edge of the bonding surface 13 is chamfered and the chamfered portion 16 is formed. Therefore, when the linear member 59 is pulled in the step (d), the linear member 59 can easily enter between the composite substrate 20 and the substrate carrier 10, and the composite substrate 20 can be peeled off more easily.

  Further, in step (d), both sides of the linear member 59 are pulled in an oblique direction inclined to the substrate carrier 10 from a direction parallel to the bonding surface 13 (lower left direction in the lower part of FIG. 5). Damage to the composite substrate 20 can be further suppressed as compared with the case of pulling in an oblique direction (upper left direction in the lower stage of FIG. 5) inclined from the parallel direction to the composite substrate 20 side.

  In step (a), a bonded substrate 30 is prepared by bonding the piezoelectric substrate 32 and the support substrate 24. In step (b), the support substrate 24 side of the bonded substrate 30 is bonded to the bonding surface 13. In the step (c), the surface of the piezoelectric substrate 32 of the adhesive 40 is polished. At this time, if the polishing is performed until the thickness of the piezoelectric substrate 32 becomes 40 μm or less in the step (c), the piezoelectric substrate 22 is easily damaged at the time of peeling from the substrate carrier 10 in the step (d). Significant to apply.

  It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that the present invention can be implemented in various modes as long as it belongs to the technical scope of the present invention.

  For example, in the above-described embodiment, the substrate carrier 10 includes the chamfered portion 16, but the chamfered portion 16 may not be provided. Further, a substrate-side protruding surface may be provided by providing a groove on the upper surface of the main body portion 12 so that the bonded substrate 30 protrudes from the groove portion.

  In the embodiment described above, the bonding surface 13 is circular, but is not limited thereto. FIG. 7 is an explanatory diagram of a substrate carrier 210 according to a modification. FIG. 7A is a top view of a substrate carrier 210 according to a modification. As shown in FIG. 7A, the bonding surface 213 of the substrate carrier 210 includes a circular region 214 and a substantially rectangular protruding region 215 that protrudes radially outward from the circular region 214. FIG. 7B is a top view showing a state in which the substrate carrier 210 and the composite substrate 20 are bonded such that at least a part of the protruding region 215 protrudes from the bonding surface of the bonded substrate 30. FIG. 7B shows a state in which the adhesive body 40 is seen through from the substrate (composite substrate 20) side in a direction perpendicular to the bonding surface 213. Further, in FIG. 7B, only the support substrate 24 of the composite substrate 20 is illustrated in order to make the drawing easy to see. In this state, a part of the protruding region 215 is a carrier-side protruding surface 213a (hatched portion in the figure). In addition, the surface on the substrate carrier 210 side of the portion of the support substrate 24 that protrudes from the adhesive surface 213 (filled portion in the figure) is a substrate-side protruding surface 226a. When viewed from the substrate side in a direction perpendicular to the bonding surface 213, the carrier-side protruding surface 213a is adjacent to the substrate-side protruding surface 226a at the first and second contacts 244a and 244b. The carrier side protruding surface 213a plays the same role as the carrier side protruding surface 13a of FIG. That is, as shown in FIG. 7B, the linear member 59 is stretched across and pulled across the carrier-side protruding surface 213a and on both sides so as to pass through the substrate-side protruding surface 226a. A force can be applied intensively to the adhesive located at the two contacts 244a, 244b.

Furthermore, it is also possible to provide two protruding regions 315 and 316 that protrude from the circular region 314 as in the substrate carrier 310 shown in FIG. FIG. 8B is a top view illustrating a state in which the substrate carrier 310 and the composite substrate 20 are bonded such that at least a part of each of the protruding regions 315 and 316 protrudes from the bonding surface of the bonded substrate 30. FIG. 8B shows a state in which the adhesive 40 is seen through from the substrate (composite substrate 20) side in a direction perpendicular to the bonding surface 313. Further, in FIG. 8B, only the support substrate 24 of the composite substrate 20 is illustrated for easy viewing of the drawing. In this state, a part of the protruding regions 315 and 316 is the carrier side protruding surfaces 313a and 313b (hatched portions in the figure). In addition, a surface on the substrate carrier 310 side (a part of the adhesive surface 26) in the portion of the support substrate 24 that protrudes from the adhesive surface 313 (the darkly filled portion in the figure) is a substrate-side protruding surface 326 a. Similarly, the surface on the substrate carrier 310 side of the portion of the support substrate 24 that protrudes from the adhesive surface 313 (the thinly painted portion in the figure) is the substrate-side protruding surface 326b. The substrate-side protruding surface 326a is adjacent to the carrier-side protruding surfaces 313a and 313b at the first and second contacts 344a and 344b. Further, the substrate-side protruding surface 326b is adjacent to the carrier-side protruding surface 313a at the contact point 344c, and the substrate-side protruding surface 326b is adjacent to the carrier-side protruding surface 313b at the contact point 344d. As described above, even when there are three or more contacts, the force may be applied to at least two contacts in a concentrated manner by the linear member 59 that is stretched. For example, as shown in FIG. 8 (b), the substrate side protruding surface 326a is crossed and the carrier side protruding surfaces 313a and 313b on both sides thereof are adjacent to the substrate side protruding surface 326a at the first contact 344a and the second contact 344b. By extending the linear member 59 so as to pass through the two surfaces), it is possible to concentrate the force on the first contact 344a and the second contact 344b.

  In FIG. 8B, the carrier-side protruding surface 313a and the carrier-side protruding surface 313b are different surfaces, but even if there is only one carrier-side protruding surface such as they are connected. Good. Even in this case, the substrate-side protruding surface 326a is adjacent to one carrier-side protruding surface by the first and second contacts 344a and 344b when viewed from the substrate side in a direction perpendicular to the bonding surface 313. As in FIG. 8B, the linear member 59 is stretched over and pulled, so that a force can be applied intensively to the first and second contacts 344a and 344b.

  In the embodiment described above, the carrier-side protruding surface 13a is adjacent to one substrate-side protruding surface 26a by the first and second contacts 44a and 44b when viewed from the substrate side in a direction perpendicular to the bonding surface 13. Although the bonding in the step (b) is performed so as to be in a state of being, it is not limited to this. The carrier side protruding surface may be adjacent to the two substrate side protruding surfaces at the first and second contacts. In other words, the substrate-side protruding surface adjacent to the carrier-side protruding surface at the first contact and the substrate-side protruding surface adjacent to the carrier-side protruding surface at the second contact may be different surfaces.

  In the embodiment described above, in the step (b), the substrate carrier 10 and the bonded substrate 30 are bonded so that the central axes of the bonding surface 13 and the bonding surface 26 are coaxial. You may stick and adhere.

  In the embodiment described above, in the step (b), the carrier side protruding surface 13a protrudes radially outward from the portion of the OF 25 in the adhesive surface 26. However, the present invention is not limited to this and protrudes from other positions. Also good.

  In the embodiment described above, the substrate to be polished is the bonded substrate 30 in FIG. 2, but is not limited thereto. For example, the bonded substrate board 30 may not have the OF 25 (and OF 33). The bonding surface 26 does not have to be circular, for example, the bonded substrate 30 is not disk-shaped. Further, the substrate to be polished is not limited to the substrate in which the piezoelectric substrate 32 and the support substrate 24 are bonded together, and may be a single substrate.

  In the embodiment described above, in the step (b), the carrier-side protruding surface 13a and the substrate-side protruding surface 26a are the first and second contact points 44a, 44a, when viewed from the substrate side in a direction perpendicular to the bonding surface 13. Although the bonded substrate 30 and the substrate carrier 10 are bonded so as to be adjacent to each other at 44b, the present invention is not limited to this. At least one of the first and second contacts 44a and 44b may not be present, and at least one of the carrier-side protruding surface 13a and the substrate-side protruding surface 26a may not be present in the adhesive 40. For example, the substrate carrier 10 provided with the bonding surface 13 having a diameter larger than the diameter of the bonding surface 26 of the bonded substrate 30 is prepared in the step (a), and the bonding surface 13 and the bonding surface 26 are formed in the step (b). The substrate carrier 10 and the bonded substrate 30 may be bonded so that the central axis is coaxial. In this case, the carrier-side protruding surface 13a exists in the adhesive 40, but the substrate-side protruding surface 26a does not exist. Alternatively, in the step (a), the substrate carrier 10 having the bonding surface 13 having a diameter smaller than the diameter of the circle concentric with the bonding surface 26 of the bonded substrate 30 and in contact with the OF 25 is prepared, and this bonding is performed in the step (b). The substrate carrier 10 and the bonded substrate 30 may be bonded so that the central axes of the surface 13 and the bonding surface 26 are coaxial. In this case, in the adhesive 40, the substrate-side protruding surface 26a exists, but the carrier-side protruding surface 13a does not exist. Even in these cases, the composite substrate 20 is peeled off in a state where the composite substrate 20 is cooled to −15 ° C. or more and 0 ° C. or less in the step (d), so that the composite substrate 20 is damaged when the composite substrate 20 is peeled off. Can be further suppressed. In addition, although work efficiency becomes worse, it may replace with the linear member 59 and may perform peeling of a process (d) using spatula members, such as a scraper. For example, the tip of the scraper may be inserted between the composite substrate 20 and the substrate carrier 10 (adhesive layer 42) from the outer peripheral surface of the adhesive 40, and the composite substrate 20 may be peeled off. By using the spatula-like member, the composite substrate 20 can be peeled even when the force from the linear member 59 cannot be applied intensively to the two adhesives.

[Example 1]
As the step (a), a ceramic substrate carrier made of alumina and a bonded substrate obtained by bonding an LT substrate and an Si substrate through an epoxy resin were prepared. The substrate carrier used was a carrier-side adhesive surface having a diameter of 120 mm on the upper surface and a chamfer of C 0.5 mm on the outer peripheral edge of the upper surface. A bonded substrate was prepared and prepared as follows. First, an LT substrate having an OF diameter of 100 mm and a thickness of 350 μm was bonded to an Si substrate having an OF diameter of 100 mm and a thickness of 230 μm via an epoxy resin. Adhesion is performed by applying an epoxy resin to the surface of the Si substrate with a spin coater (rotation speed 1000 rpm) so as to have a film thickness of 1 μm, bonding the Si substrate and the LT substrate, and curing the resin in an oven at 150 ° C. It was. Subsequently, the surface of the LT substrate opposite to the bonding surface with the Si substrate was ground with a grinder, and the thickness of the LT substrate was set to 12 μm to obtain a bonded substrate.

  In step (b), the surface of the Si substrate opposite to the bonding surface with the LT substrate was bonded to the carrier-side bonding surface of the substrate carrier with wax to obtain an bonded body. Adhesion was performed as follows. First, the bonded substrate was heated to 90 ° C., and wax was applied to the bonding surface on the bonded substrate side with a spin coater (rotation speed: 1000 rpm) so as to have a film thickness of 1 μm. Then, the bonded surface on the bonded substrate side and the carrier-side bonded surface were bonded so that the central axis was coaxial, and pressed to obtain an bonded body. The diameter of the carrier side adhesive surface was larger than the diameter of the bonded surface on the bonded substrate side, and the adhesive surface was bonded coaxially, so there was no substrate-side protruding surface in the adhesive.

  As the step (c), the surface of the LT substrate of the adhesive was polished. Specifically, the LT substrate side is pressed against a lapping machine equipped with a tin plate with a diameter of 350 mm, and the lapping (rough polishing) is performed for 1 hour by rotating the platen and the substrate carrier while supplying diamond slurry. It was. Thereby, the thickness of the LT substrate became about 2 μm. Subsequently, CMP (final polishing) was performed for 2 hours while supplying colloidal silica using a CMP polishing machine, so that the thickness of the LT substrate was about 0.6 μm. As a result, the bonded substrate was a composite substrate (polished substrate) obtained by polishing the LT substrate.

  In step (d), the adhesive was placed on a Peltier cooling plate and allowed to stand for 20 minutes to cool the surface temperature of the composite substrate to −5 ° C. A scraper was inserted between the composite substrate and the substrate carrier to separate the composite substrate. The surface temperature of the composite substrate immediately before peeling was −0.3 ° C. Thereby, a composite substrate was obtained.

[Example 2]
Example 2 is the same as Example 1 except that the set temperature and cooling time of the Peltier cooling plate in step (d) are changed and the surface temperature of the composite substrate immediately before peeling is set to -14.5 ° C. Thus, a composite substrate was produced.

[Comparative Examples 1-3]
As Comparative Examples 1 to 3, the set temperature and cooling time of the Peltier cooling plate in the step (d) were changed, and the surface temperatures of the composite substrates immediately before peeling were set to −18.3 ° C., 5.8 ° C., and 10.3, respectively. A composite substrate was produced in the same manner as in Example 1 except that the temperature was changed to ° C.

[Comparative Example 4]
As Comparative Example 4, a composite substrate was produced in the same manner as in Example 1 except that the adhesive body was heated to 90 ° C. in Step (d), the wax was melted, and the composite substrate was peeled from the substrate carrier.

  50 composite substrates were produced in each of Examples 1 and 2 and Comparative Examples 1 to 4, and the number of cracks in the produced composite substrate (composite substrate after peeling) was counted to determine the probability of cracking (%). Calculated. The cracking probabilities in Examples 1 and 2 and Comparative Examples 1 to 4 were 4%, 2%, 8%, 16%, 32%, and 84%, respectively.

[Example 3]
A composite substrate was fabricated in the same manner as in Example 1 except for the following points. In the step (a), a substrate carrier having a carrier side adhesive surface diameter of 97 mm (a value smaller than the diameter of the bonded substrate side adhesive surface) was prepared. In the step (b), the bonded surface on the bonded substrate side and the carrier-side bonded surface were bonded so that the central axis was coaxial. As a result, as in FIG. 3, there was a carrier-side protruding surface in which a part of the carrier-side bonding surface protruded from a part of the OF portion of the Si substrate in the bonding surface on the bonded substrate side. Similarly to FIG. 3, when viewed through the bonded substrate side in a direction perpendicular to the carrier side adhesive surface, the carrier side protruding surface is adjacent to the substrate side protruding surface at the first and second contacts. It was. In step (d), as in FIG. 5, the linear member was stretched across the carrier-side protruding surface and on both sides so as to pass the substrate-side protruding surface side of the composite substrate. Then, both sides of the linear member were pulled in an oblique direction inclined from the direction parallel to the carrier side adhesive surface to the substrate carrier side, and the composite substrate was peeled off from the substrate carrier. As the linear member, a thread made of nylon and having a thickness of 0.2 mm was used. Moreover, the temperature of the surface of the composite substrate before peeling in the step (d) was −2 ° C.

  When 50 composite substrates were produced according to Example 3, the composite substrate was not broken at all, and the probability of cracking was even smaller than that of Example 1 (0%).

  10, 210, 310 Substrate carrier, 12 Main body, 13, 213, 313 Adhesive surface, 13a, 213a, 313a, 313b Carrier side protruding surface, 14 Shaft, 16 Chamfered portion, 20 Composite substrate, 22 Piezoelectric substrate, 24 Support substrate , 25 Orientation flat (OF), 26 Adhesive surface, 26a, 226a, 326a, 326b Substrate side protruding surface, 30 Bonded substrate, 32 Piezoelectric substrate, 33 Orientation flat (OF), 40 Adhesive, 42 Adhesive layer, 44a, 244a, 344a first contact, 44b, 244b, 344b second contact, 344c, 344d contact, 50 polishing device, 52 surface plate, 54 shaft, 56 polishing cloth, 58 pipe, 59 linear member, 214, 314 circular region, 215, 315, 316 protruding Pass.

Claims (5)

(A) a step of preparing a substrate and a substrate carrier having a carrier-side bonding surface for bonding the substrate;
(B) adhering the substrate to the carrier-side adhesive surface via an adhesive to form an adhesive body; and (c) polishing the surface of the substrate opposite to the adhesive surface with the substrate carrier. And a polishing substrate,
(D) peeling the polishing substrate from the substrate carrier in a state where the polishing substrate is cooled to −15 ° C. or more and 0 ° C. or less;
Only including,
In the step (a), the substrate having an orientation flat is prepared,
In the step (b), both ends of the orientation flat are provided with a substrate-side protruding surface that protrudes from the carrier-side adhesive surface, and a part of the carrier-side adhesive surface is provided with a carrier-side protruding surface that protrudes from the orientation flat. Adhering the substrate and the substrate carrier so that
In the step (d), the linear member is stretched across the carrier-side protruding surface and on both sides thereof so as to pass through the substrate-side protruding surface side, and the both sides of the linear member are pulled. Peeling the polishing substrate from the substrate carrier;
A method for producing a polishing substrate. In the step (a), the substrate carrier in which the outer peripheral edge of the carrier side adhesive surface is chamfered is prepared.
The method for manufacturing a polishing substrate according to claim 1 . In the step (d), the polishing substrate is pulled to the substrate carrier by pulling both sides of the linear member in a direction parallel to the carrier-side adhesive surface or in an oblique direction inclined from the parallel direction to the substrate carrier side. Peel off from the
The manufacturing method of the grinding | polishing board | substrate of Claim 1 or 2 . In the step (a), the substrate on which the piezoelectric substrate and the support substrate are bonded together is prepared,
In the step (b), the support substrate side of the substrate is bonded to the carrier-side bonding surface to form the bonded body,
In the step (c), the surface of the piezoelectric substrate of the adhesive is polished.
The manufacturing method of the grinding | polishing board | substrate of any one of Claims 1-3 . In the step (c), the polishing is performed until the thickness of the piezoelectric substrate is 0.1 μm or more and 40 μm or less.
The manufacturing method of the grinding | polishing board | substrate of Claim 4 .

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