JP2009289882A - Carrier plate and polishing device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a carrier plate preventing a mark used for specifying a wafer sticking position arranged in the carrier plate from being not recognized by loss or disappearance due to friction with a supporting roller, and by breakage at the time of handling. <P>SOLUTION: The carrier plate 1 is formed of disk-like ceramic. One main face is set to be a sticking face of a wafer 5, and a depression 2 is given to a side by leaving a flush side part on a sticking face side in a circumferential direction with the side. A mark 3 whose color tone differs from that of ceramic is formed on a base of the depression 2. At the time of polishing the wafer 5, a trouble is not given to support and rotation by the supporting roller 18, and an amount of polishing solution 16 invading the depression 2 is suppressed. Even if polishing solution 16 is stuck to the side of the carrier plate 1, the supporting roller 18 is not brought into contact with the mark 3. Thus, a possibility that the mark 3 is lost or disappears can be reduced. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a wafer bonding apparatus and a carrier plate used for a wafer polishing apparatus.

  Conventionally, for polishing a surface of a wafer made of silicon, gallium arsenide, or the like used for manufacturing a semiconductor element, a wafer bonding apparatus and a carrier for attaching the wafer to a disk-shaped carrier plate made of ceramics such as alumina or silicon carbide A polishing apparatus that polishes a wafer attached to a plate is used.

FIG. 5 is a schematic view showing an example of a conventional wafer bonding apparatus.
This wafer bonding apparatus 50 includes a turntable 57 on which the carrier plate 51 is placed, a rotation control device 59 that controls the rotation of the turntable 57, a suction pad 58 that sucks the wafer 55 and conveys it onto the carrier plate 51, It is composed of In the method of attaching the wafer 55 to the carrier plate 51, first, the carrier plate 51 is placed on the turntable 57. Next, the wafer 55 is adsorbed by the adsorbing pad 58, applied with the adhesive 54, and then transported and pasted onto the carrier plate 51. Further, by rotating the turntable 57 by the rotation control device 59 and securing a bonding portion for another wafer 55, a plurality of wafers 55 can be bonded to the carrier plate 51.

6A and 6B show an example of a conventional wafer polishing apparatus. FIG. 6A is a schematic cross-sectional view, and FIG. 6B is a schematic view showing a rotation direction of a polishing surface plate and a carrier plate of the polishing apparatus.
The polishing apparatus 60 includes a carrier plate 51 made of a disk-shaped ceramic, a pressing portion 61 that presses and rotates the carrier plate 51, a support roller 68 that supports and rotates the side surface of the carrier plate 51, and a carrier plate A wafer polishing surface plate 64 composed of a cross 62 and a rotary table 63 for polishing the surface of the wafer 55 attached to 51 via an adhesive 54, and a rotating shaft 65 for rotating the wafer polishing surface plate 64. The nozzle 67 supplies the polishing liquid 66 onto the wafer polishing surface plate 64.

  The polishing method of the wafer 55 using this polishing apparatus 60 is performed by using the wafer bonding apparatus 50 of the example shown in FIG. 5 to attach the wafer 55 to the bonding surface which is one main surface via the adhesive 54. The carrier plate 51 is placed on the wafer polishing surface plate 64 so that one main surface of the carrier plate 51, that is, the processing surface of the wafer 55 faces the wafer polishing surface plate 64, and the carrier plate 51 is supported by the support roller 68. Support the sides. Next, a rotatable pressing portion 61 is set on the other main surface of the carrier plate 51. Then, while supplying the polishing liquid 66 from the nozzle 67 onto the wafer polishing surface plate 64, the wafer polishing surface plate 64 is rotated by the rotational force transmitted from the power source (not shown) to the rotating shaft 65, and the carrier plate 51 is rotated. The other main surface is pressed by the pressing portion 61.

  When the wafer polishing surface plate 64 rotates in this way, the supplied polishing liquid 66 moves on the surface of the wafer polishing surface plate 64 toward the outer periphery by centrifugal force due to rotation, and the wafer 55 and the wafer polishing surface plate 64 It enters the surface, that is, the contact surface with the cloth 62. Further, as in the example shown in FIG. 6B, the carrier plate 51 is supported at the position supported by the support roller 68 by the frictional force between the adhered wafer 55 and the wafer polishing surface plate 64. By rotating in the same direction as the board 64, the surface of the wafer 55 is polished.

  After the polishing, the adhesive 54 is dissolved using various solvents to peel the wafer 55 from the carrier plate 51, and the carrier plate 51 after the wafer 55 is peeled off is repeatedly used after being cleaned with various solvents. However, the carrier plate 51 has a slight difference in surface accuracy between the portion where the wafer 55 is attached and the portion where the wafer 55 is not attached, and the wafer 55 is attached to the portion where the surface accuracy is different. When polished, there is a problem that the surface accuracy of the polished wafer 55 is affected.

  With respect to this problem, in Patent Document 1, a mark (identifier) is provided on a carrier plate (wafer affixing plate), a sensor for detecting the mark is provided, and the carrier plate is positioned in a circumferential position by a detection signal of the sensor. There has been proposed a wafer bonding apparatus that can be positioned at the same position so that the wafer bonding position is always the same. According to this, even if there is a slight difference in surface accuracy between the portion where the wafer is attached and the portion where the wafer is not attached on the wafer attachment surface of the carrier plate, the wafer attachment surface is always homogeneous. Since the wafer can be attached at the same position above, the surface accuracy of the wafer is not affected. Further, it is described that the mark forms a recess from the wafer attachment surface to the side surface, and the mark is put in the recess to cover and cover the transparent member or to be filled with a transparent substance. Has been.

Patent Document 2 proposes a wafer bonding apparatus provided with a mark on a carrier plate and provided with a plurality of mark detectors for detecting the mark. According to this, the mark position can be quickly detected as a reference position by any one of a plurality of mark detectors, and the wafer attachment position on the carrier plate can be determined based on the reference position. It is described that the wafer can be attached to a fixed position of the carrier plate, or the entire surface of the carrier plate can be used uniformly by shifting the attaching position little by little.
Japanese Utility Model Publication No.8-1330 JP 2000-84839 A

  However, in the wafer bonding apparatus described in Patent Documents 1 and 2, since the mark is provided from the bonding surface of the carrier plate or from the bonding surface to the side surface, the wafer bonding apparatus can accurately detect the mark. However, in the subsequent polishing of the wafer surface with the polishing apparatus, the side surface of the carrier plate is brought into contact with the support roller, and polishing is performed. As a result of the friction, the marks on the side surface are damaged and worn, and the marks are lost or lost, which makes it impossible to recognize the marks when attaching the wafer.

  In addition, since the mark is provided from the attachment surface to the side surface of the carrier plate, that is, at the edge portion that is the boundary between the attachment surface and the side surface, the edge portion is accidentally bumped against another when handling the carrier plate. There was a problem that sometimes the mark could be damaged. In addition, when the mark is provided by bonding a transparent member and filling the recess with a transparent substance, there is a problem that the cost for providing the mark increases.

  The present invention has been devised to solve the above-described problems in the prior art, and the mark used for specifying the wafer attachment position provided on the carrier plate is the friction with the support roller. It is an object of the present invention to provide a carrier plate capable of preventing a loss or disappearance due to the occurrence of damage due to damage or loss during handling, and to provide a polishing apparatus using the carrier plate.

  The carrier plate of the present invention is made of a disk-shaped ceramic, and has one main surface as a wafer attachment surface, and a side surface portion that is flush with the side surface in the circumferential direction on the attachment surface side. It has a depression, and has a mark having a color tone different from that of the ceramics on the bottom surface of the depression.

  Moreover, the carrier plate of the present invention is characterized in that, in the above configuration, the second side surface portion that is flush with the side surface in the circumferential direction is provided from the depression on the side surface to the other main surface side. Is.

  The carrier plate according to the present invention is characterized in that, in any of the above-described configurations, the surface of the mark is located between the bottom surface and the side surface of the recess.

  Moreover, the carrier plate of the present invention is characterized in that, in any of the above configurations, the mark is formed by laser light irradiation.

  The carrier plate according to the present invention is characterized in that, in any of the above-described configurations, the mark is made of a plate member having a color tone different from that of the ceramic.

  The carrier plate according to the present invention is characterized in that, in any of the above-described configurations, the ceramic is made of any one of alumina, zirconia, cordierite, silicon carbide, silicon nitride, and aluminum nitride.

  The polishing apparatus of the present invention is characterized in that the carrier plate of the present invention having any one of the above-described configurations is provided as a wafer polishing component.

  According to the carrier plate of the present invention, it is made of a disk-shaped ceramic, and one main surface is used as a wafer attachment surface, and the side surface has a side surface portion that is flush with the side surface on the attachment surface side in the circumferential direction. Because it has a dent and has a mark with a color tone different from that of ceramics on the bottom of the dent, even if the polishing liquid adheres to the side of the carrier plate and enters the dent, Since the supporting roller and the mark to be supported do not come into contact with each other, there is little possibility that the mark is lost or lost. Further, since the side surface portion is flush with the side surface in the circumferential direction between the depression and the attachment surface, there is little possibility of hindering support and rotation of the carrier plate by the support roller. Furthermore, since the mark is provided on the bottom surface of the recess, it is protected by a step between the side surface and the recess, and there is little risk of the mark being lost when handling the carrier plate. Therefore, accurate positioning of the wafer and accurate polishing information can be obtained.

  Further, according to the carrier plate of the present invention, when the second main surface side is flush with the side surface from the side depression to the other main surface side, the support for supporting the side surface of the carrier plate is provided. Since the contact area when the roller passes through the depression can be increased, and the roller can be supported evenly above and below the depression, the carrier plate can be stably supported and rotated.

  Further, according to the carrier plate of the present invention, when the surface of the mark is located between the bottom surface and the side surface of the recess, the polishing liquid adheres to the side surface of the carrier plate, and the recess is caused by friction with the support roller. Even if the polishing liquid penetrates, the polishing liquid is less likely to adhere to the surface of the mark, and the mark surface and the support roller are not in contact with each other, thereby further reducing the possibility of the mark being lost or lost. Can do. Therefore, the wafer can be polished with high accuracy while holding the mark stably for a longer period of time.

  Further, according to the carrier plate of the present invention, when the mark is caused by laser light irradiation, the mark may be dissolved and lost or lost even if various solvents are used for cleaning the carrier plate. Few.

  Also, according to the carrier plate of the present invention, when the mark is made of a plate member having a color tone different from that of ceramics, the mark may be dissolved and lost or lost even if various solvents are used for cleaning the carrier plate. Less is.

  Further, according to the carrier plate of the present invention, when the ceramic is made of any one of alumina, zirconia, cordierite, silicon carbide, silicon nitride, and aluminum nitride, the carrier plate is bent because of high rigidity. Since it is difficult and has high corrosion resistance that can withstand cleaning with various solvents, a wafer with high flatness can be obtained.

  Further, according to the polishing apparatus of the present invention, since the carrier plate of the present invention is used as a wafer polishing component, the mark can be stably held and detected, and a wafer with high flatness can be detected over a long period of time. Can be obtained.

  Hereinafter, examples of embodiments of the carrier plate of the present invention and a polishing apparatus using the same will be described.

FIG. 1 is a schematic view showing an example of a wafer attaching apparatus for attaching a wafer to a carrier plate of the present invention.
The wafer bonding apparatus 10 includes a turntable 7 on which a carrier plate 1 is placed, a mark detector 6 that detects a mark 3 provided on the carrier plate 1, and a wafer 5 that is sucked and transferred onto the carrier plate 1. And a rotation control device 9 that controls the rotation of the turntable 7 based on the position information of the carrier plate 1 obtained from the mark detector 6.

  In the method of attaching the wafer 5 to the carrier plate 1, first, the carrier plate 1 is placed on the turntable 7 with the attachment surface of the wafer 5, which is one main surface, facing up. Next, the turntable 7 is rotated by the rotation control device 9, the mark 3 provided on the carrier plate 1 is detected by the mark detector 6, and the carrier plate 1 is positioned. Thereafter, the wafer 5 is sucked by the suction pad 8 and the adhesive 4 is applied, and then conveyed and pasted on the carrier plate 1. When the next wafer 5 is attached, the turntable is moved by the amount of displacement from the reference position detected by the mark detector 6 determined by the rotation control device 9 in order to secure the attachment portion of the next wafer 5. 7 is rotated to attach the next wafer 5. By repeating this, a plurality of wafers 5 can be attached to the attachment surface of the carrier plate 1.

  Thus, the carrier plate 1 of the present invention is made of disk-shaped ceramics, and has one main surface as a bonding surface of the wafer 5, and the side surface is flush with the side surface on the bonding surface side in the circumferential direction. It is important to have a recess 2 at a portion, and to have a mark 3 having a color tone different from that of ceramics on the bottom surface of the recess 2. Thus, since the carrier plate 1 has a mark having a color tone different from that of ceramics, the mark 3 can be easily detected and recognized, and the attachment position of the wafer 5 is positioned at a fixed position, or It can be controlled by sequentially displacing.

  2A and 2B show an example of an embodiment of a polishing apparatus provided with the carrier plate of the present invention as a wafer polishing component. FIG. 2A is a schematic sectional view, and FIG. 2B is a polishing surface plate of the polishing apparatus. It is the schematic which shows the rotation direction of a carrier plate.

  The polishing apparatus 20 of the present invention includes a carrier plate 1 of the present invention, a pressing portion 11 that can rotate while pressing the carrier plate 1, a support roller 18 that supports and rotates the side surface of the carrier plate 1, and the carrier plate 1. A wafer polishing surface plate 14 composed of a cloth 12 and a rotary table 13 for polishing the surface of the wafer 5 attached to the substrate 5 with an adhesive 4, a rotating shaft 15 for rotating the wafer polishing surface plate 14, The nozzle 17 is configured to supply the polishing liquid 16 onto the wafer polishing surface plate 14.

  The polishing method of the wafer 5 using the polishing apparatus 20 is performed by using the wafer bonding apparatus 10 shown in FIG. 1 to attach the wafer 5 to the bonding surface which is one main surface via the adhesive 4. The carrier plate 1 is placed on the wafer polishing surface plate 14 so that one main surface of the carrier plate 1, that is, the processing surface of the wafer 5 faces the wafer polishing surface plate 14, and the carrier plate 1 is supported by the support roller 18. Support the sides. Next, a rotatable pressing portion 11 is set on the other main surface of the carrier plate 1. Then, while supplying the polishing liquid 16 from the nozzle 17 onto the wafer polishing platen 14, the wafer polishing platen 14 is rotated by the rotational force transmitted from the power source (not shown) to the rotating shaft 15, and the carrier plate 1. The other main surface is pressed by the pressing portion 11.

  As described above, when the wafer polishing platen 14 rotates, the supplied polishing liquid 16 moves on the surface of the wafer polishing platen 14 toward the outer periphery by the centrifugal force caused by the rotation, and the wafer 5 and the wafer polishing platen 14 are moved. Enters the surface of the surface, that is, the contact surface with the cloth 12. Further, as in the example shown in FIG. 6B, the carrier plate 1 is supported by the frictional force between the attached wafer 5 and the wafer polishing surface plate 14 at the position where the side surface is supported by the support roller 18. By rotating in the same direction as the polishing surface plate 14, the surface of the wafer 5 can be polished. The rotational speed of the wafer polishing surface plate 14 can be controlled at various rotational speeds from a low speed to a high speed by a rotation control unit (not shown) installed in the polishing apparatus 20.

  2B, a mark detector 6 for detecting the mark 3 is provided on the side of the carrier plate 1, and the mark detector 6 is provided on the bottom surface of the depression 2 on the side surface of the carrier plate 1. The detected mark 3 is detected, the number of passes of the mark 3, that is, the data of the number of detections is sent to the rotation control unit, and the rotation condition for obtaining the optimum machining accuracy can be set based on this data.

  In the polishing of the wafer 5 using the polishing apparatus 20, the carrier plate 1 of the present invention has the depression 2 on the side surface, with the side surface portion being flush with the side surface in the circumferential direction on the bonding surface side. There is little risk of hindering support and rotation by the support roller 18 used in contact with the side surface. Further, since the bottom surface of the recess 2 has the mark 3 having a color tone different from that of ceramics, even if the polishing liquid 16 adheres to the side surface of the carrier plate 1, the support roller 18 and the mark 3 do not come into contact with each other. There is little possibility that the mark 3 is lost or lost due to the effect of 16.

  Then, after polishing the wafer 5, the adhesive 4 is dissolved using a solvent or the like, and the wafer 5 is peeled off from the carrier plate 1. The carrier plate 1 from which the wafer 5 has been peeled off is again attached after cleaning by the wafer attaching apparatus 10 shown in FIG. At this time, the carrier plate 1 of the present invention can maintain a state in which the mark 3 can be satisfactorily identified without being lost or lost during polishing of the wafer 5 using the polishing apparatus 20. Therefore, it is possible to control the position of attaching the wafer 5 to a fixed position or sequentially shifting the position.

  FIG. 3 shows an example of an embodiment of a carrier plate according to the present invention. FIG. 3A is a perspective view of a carrier plate having a recess on one main surface side of the side surface with a side surface portion that is flush with the side surface in the circumferential direction. It is a figure, (b) is a perspective view of the carrier plate which has a hollow also in the other main surface side, and has the 2nd side surface part which is flush with the side surface in the circumferential direction.

  As in the example shown in FIG. 3A, the carrier plate 1 of the present invention is made of a disk-shaped ceramic, and has one main surface as the wafer attachment surface 30 and the side surface 31 on the attachment surface 30 side. The side surface portion 32 is flush with the side surface 31 in the circumferential direction and has a recess 2, and the bottom surface 33 of the recess 2 has a mark 3 having a color tone different from that of ceramics. By using the carrier plate 1 having such a configuration, the mark 3 is provided on the bottom surface 33 of the recess 2 instead of the attachment surface 30 or the side surface 31 of the wafer 5, so that the polishing liquid 16 is applied to the side surface of the carrier plate 1. Even if it adheres, the adverse effect on the mark 3 is suppressed, and the support roller 18 and the mark 3 are not in contact with each other, so that there is little possibility that the mark 3 is lost or lost.

  Further, since the side surface portion 32 which is flush with the side surface 31 in the circumferential direction is provided on the bonding surface 30 side, that is, the polishing surface side of the wafer 5, the carrier plate 1 by the support roller 18 used in contact with the side surface 31. There is little risk of hindering the support and rotation, and the presence of the side surface portion 32 that is flush with the side surface 31 in the circumferential direction can suppress the amount of the polishing liquid 16 that enters the recess 2.

  Thus, since the mark 3 provided on the carrier plate 1 of the present invention is less likely to be lost or lost, the mark 3 is detected well by the mark detector 6 and the set rotation condition is reliably implemented. Therefore, it is possible to polish the wafer 5 stably and accurately over a long period of time. Further, the mark 3 has a color tone different from that of the ceramics constituting the carrier plate 1 and has a different light reflectance, so that the mark 3 can be easily detected and recognized by the mark detector 6 such as an optical sensor.

  In addition, the carrier plate 1 of the present invention has a second side surface portion 34 that is flush with the side surface 31 in the circumferential direction from the recess 2 of the side surface 31 to the other main surface side, as in the example shown in FIG. It is preferable to have. By using the carrier plate 1 having such a configuration, the possibility that the mark 3 is lost or lost is reduced as in the case of the carrier plate 1 in the example shown in FIG. Further, when the second side surface portion 34 that is flush with the side surface 31 is provided from the recess 2 of the side surface 31 to the other main surface side, the support roller 18 that supports the side surface 31 of the carrier plate 1 is provided. Since the contact area when passing through the recess 2 can be increased, and the support roller 18 can be supported in a balanced manner above and below the recess 2 to provide a rotational force, the carrier plate 1 can be stably provided. It can be supported and rotated.

  FIG. 4 shows another example of the embodiment of the carrier plate of the present invention. (A) is a perspective view of the carrier plate in which the surface of the mark is located between the bottom surface and the side surface of the depression. b) is a sectional view taken along line AA ′ in FIG.

  As in the example shown in FIG. 4, in the carrier plate 1 of the present invention, the surface of the mark 3 is preferably located between the bottom surface 33 and the side surface 31 of the recess 2. With this configuration, during polishing of the wafer 5 using the polishing apparatus 20, the polishing liquid adheres to the side surface 31 of the carrier plate 1, and the polishing liquid enters the recess 2 due to friction with the support roller 18. Even so, when the surface of the mark 3 is located between the bottom surface 33 and the side surface 31 of the recess 2, the polishing liquid hardly adheres to the surface of the mark 3, and the surface of the mark 3 and the support roller Since there is no contact with 18, it is possible to further reduce the possibility that the mark 3 is lost or disappears. Therefore, it is possible to polish the wafer 5 with high accuracy over a longer period.

Moreover, it is preferable that the carrier plate 1 of this invention is what the mark 3 was provided by what is called laser processing by irradiation of a laser beam. Since the carrier plate 1 is cleaned with various solvents after the wafer 5 is peeled off, it is necessary to provide the carrier plate 1 so that the mark 3 does not dissolve and disappear during this cleaning. Therefore, a resin composition serving as a carbon source, for example, a thermoplastic polyester resin blended with carbon and titanium oxide, a polyamide resin blended with a salt of an amino group-containing triazine, or the like is applied to the portion where the mark 3 is provided in advance. It is preferable to provide a mark 3 having a color tone different from that of ceramics by irradiating the substrate with a CO ₂ laser beam, a YAG laser beam, or the like to cause chemical reaction.

  As for the shape of the mark 3, any shape such as a circular shape, a triangular shape, a quadrangular shape, other polygonal shapes, a bar code or other characters provided in the depression 2 so as not to protrude from the side surface 31 can be used. Even if it is such a shape, it is applicable.

  In the carrier plate 1 of the present invention, the mark 3 is preferably made of a plate member having a color tone different from that of ceramics. In order to prevent the mark 3 from dissolving and disappearing when the carrier plate 1 is washed with various solvents, it is rarely dissolved by the solvent used, and a metal or ceramic having a color tone different from that of the ceramic constituting the carrier plate 1 is used. It is preferable that the plate is processed into a mark 3 as a plate member. The plate member may be provided with a mark 3 made of a plate member by being attached using an adhesive that can withstand washing of various solvents, or by being fitted by shrink fitting or cold fitting.

  In the carrier plate 1 of the present invention, the ceramic is preferably made of any one of alumina, zirconia, cordierite, silicon carbide, silicon nitride, and aluminum nitride. The carrier plate 1 is required to have high rigidity that does not deform during polishing of the wafer 5 and high corrosion resistance that can withstand cleaning with various solvents, but all of alumina, zirconia, cordierite, silicon carbide, silicon nitride, and aluminum nitride are high. Since it has rigidity and corrosion resistance, it is a ceramic suitable for the carrier plate 1 of the present invention. Among these materials, alumina is particularly suitable as a material used for the carrier plate 1 because the raw material unit price is low and the attaching surface of the wafer 5 of the carrier plate 1 can be processed with higher accuracy. It is.

  Further, the polishing apparatus 20 of the present invention as shown in FIG. 2 using the carrier plate 1 of the present invention as a polishing component for the wafer 5 can obtain the wafer 5 with high flatness over a long period of time. is there.

Next, an example of the manufacturing method of the carrier plate 1 of this invention is demonstrated.
First, disk-shaped ceramics that serve as the base of the carrier plate 1 of the present invention are manufactured. Here, as the ceramic material used for the carrier plate 1, an example in which alumina having a low raw material unit price and good workability will be described.

  As a raw material, a primary alumina raw material having a purity of 99% or more and an average particle size of 0.5 to 5 μm is prepared, and a binder and a solvent are added thereto to form a slurry, followed by spray granulation with a spray dryer to obtain alumina 2 The next raw material is prepared. Next, the alumina secondary raw material is molded into a disk shape by a hydrostatic pressure press molding method (rubber press method) at a molding pressure of 50 to 150 MPa. Cutting is performed so that the disk-shaped molded body has a predetermined outer diameter and thickness. Next, the disk-shaped molded body that has been subjected to the cutting process is fired in a firing furnace under the firing conditions at a maximum temperature of 1500 to 1700 ° C. to obtain a disk-shaped sintered body.

  After that, grinding is performed on both main surfaces and side surfaces of the disc-shaped sintered body, and chamfering processing is performed on the edge portion that is the boundary between both main surfaces and the side surfaces, so that the outer diameter is 300 to 1500 mm. A disk-shaped sintered body having a diameter of 10 to 50 mm is obtained. After that, in order to machine both main surfaces of this disk-shaped sintered body into a highly accurate flat surface, both main surfaces are ground using a large surface grinder, and both are further processed by a large polishing machine. Polishing is performed until the roughness and flatness of the main surface become several μm or less. In particular, one main surface, which is the wafer attachment surface, is polished until a roughness or flatness of several nanometers is obtained while increasing the number of the polishing surface plate of the polishing machine. In addition, about the measurement of surface shape, it implements using a straightness meter and a flatness measuring device.

  Regarding the formation of the recess 2 performed thereafter, an example of manufacturing the recess 2 of the carrier plate 1 in the example shown in FIG.

First, after finishing polishing of both main surfaces of the disk-shaped sintered body, the side surface 31 is ground, and further, the side surface 31 is formed on the side surface 31 on the bonding surface 30 side of the wafer 5 by a universal grinding machine. And a recess 2 having a side surface portion 32 that is flush with the circumferential direction. Next, the resin composition is applied to the bottom surface 33 of the recess 2 so as to have the desired mark 3 shape and dried, and then the mark 3 is irradiated with CO ₂ laser light, YAG laser light, or the like. The present invention of the example shown in FIG. 3 (a) is made of a disc-like alumina sintered body by providing a mark 3 made of alumina carbide by reacting alumina and a resin composition by instantaneously heating to high temperature. The carrier plate 1 can be obtained.

  Other materials can also be manufactured in the same process by changing the firing conditions such as the maximum temperature and preparing a similar disk-shaped sintered body. Further, during grinding by the universal grinding machine, the side surface portion 32 is flush with the side surface 31 on the bonding surface 30 side of the wafer 5 and is flush with the side surface 31 on the other main surface side. By grinding so that the second side surface portion 34 remains and providing the mark 3 on the bottom surface 33 of the recess 2, the carrier plate 1 of the example of the present invention shown in FIG. 3B can be obtained. Further, by providing the mark 3 by grinding so that the surface of the mark 3 is positioned between the bottom surface 33 and the side surface 31 of the recess 2, the carrier plate 1 of the example of the present invention shown in FIG. 4 can be obtained. .

  As for the mark 3, in particular, when the ceramic is a white material, a clear black mark 3 can be obtained by applying a resin composition and irradiating laser light in the same manner. In the case of a black material, the white mark 3 can be formed by applying a special laser marking resin and irradiating it with laser light.

  Details of the embodiments of the present invention will be described below.

(Example 1)
The carrier plate 1 of the present invention and the conventional carrier plate are manufactured, the wafer 5 is attached to these carrier plates using the wafer attaching apparatus 10 shown in FIG. 1, and the polishing apparatus 20 shown in FIG. The wafer 5 was polished using the above.

  First, the disk-shaped ceramics used as the base of the present invention and the conventional carrier plate were manufactured. As a raw material, an alumina primary raw material having a purity of 99% or more and an average particle diameter of 1 μm is prepared, and a binder and a solvent are added to form a slurry, followed by spray granulation with a spray dryer, and then an alumina secondary raw material. Got. Next, using this alumina secondary material, a disk-shaped molded body was obtained by a wet isostatic press molding method (rubber press method) at a molding pressure of 100 MPa. And it cut so that this disk-shaped molded object might become a predetermined | prescribed outer diameter and thickness. Next, the disk-shaped molded body that had been subjected to the cutting process was fired in a firing furnace under the firing conditions at a maximum temperature of 1600 ° C. to obtain a disk-shaped sintered body.

  Next, grinding is performed on both main surfaces and side surfaces of the disk-shaped sintered body, and chamfering processing is performed on the edge portion that is the boundary between both main surfaces and the side surfaces, whereby the outer diameter is 500 mm and the thickness is increased. A 25 mm disk-shaped sintered body was obtained. After that, in order to process both main surfaces of this disk-shaped sintered body into a flat surface with high accuracy, after roughing both main surfaces using a large surface grinder, a large polishing machine is used. Then, the surface was polished until the surface roughness was 1.5 μm or less and the flatness was 1 μm or less. After polishing, the side surface was further finished with a universal grinder or the like to produce a disk-shaped alumina sintered body, and four of them were prepared.

Next, the obtained disk-shaped alumina sintered body was processed by a universal grinding machine, and the carrier plate 1 of the example of the present invention shown in FIGS. 3A and 3B was manufactured. The first disk-shaped alumina sintered body is provided with a recess 2 having a side surface portion 32 that is flush with the side surface 31 on the bonding surface 30 side of the wafer 5, and a second disk. A side surface portion 32 that is flush with the side surface 31 in the circumferential direction on the bonding surface 30 side of the wafer 5 is placed on the shaped alumina sintered body, and the other main surface side is also flush with the side surface 31 in the circumferential direction. The depression 2 was provided so that the second side surface portion 34 remained. And after applying the thermoplastic polyester resin which mix | blended carbon and titanium oxide as a resin composition so that it may become the shape of the circular mark 3 to the bottom face 33 of these hollows 2, hot air of 50-100 degreeC is applied for about 30 minutes. Then, the sample is irradiated with CO ₂ laser light and then irradiated with a CO ₂ laser beam to form a black circular mark 3 with a diameter of 15 mm, which is an example of the present invention shown in FIGS. 3 (a) and 3 (b), respectively. Carrier plate 1 was obtained.

Next, with respect to the third disk-shaped alumina sintered body, a side surface portion 32 that is flush with the side surface 31 on the bonding surface 30 side of the wafer 5 is provided on the other main surface side. A universal grinding machine is used so that the second side surface portion 34 that is flush with the side surface 31 remains in the circumferential direction, and that the surface of the mark 3 is located between the bottom surface 33 and the side surface 31 of the recess 2. And ground. Then, after coating the thermoplastic polyester resin blended with carbon and titanium oxide on the surface portion serving as the resin composition of the marks 3, dried by blowing a 50 to 100 ° C. hot air about 30 minutes, CO ₂ laser beam Was applied to form a black circular mark 3 with a diameter of 15 mm, and the carrier plate 1 of the present invention of the example shown in FIG. 4 was obtained.

Next, after applying a thermoplastic polyester resin compounded with carbon and titanium oxide as a resin composition on the surface of the portion of the fourth disk-shaped alumina sintered body from the wafer attachment surface to the side surface A conventional carrier plate was obtained by applying a hot air of 50 to 100 ° C. for about 30 minutes, drying, irradiating with CO ₂ laser light, and providing a mark on the portion from the wafer attachment surface to the side surface. .

  Next, using the present invention and the conventional carrier plate, the wafer 5 is attached to the attaching surface 30 using the wafer attaching apparatus 10 shown in FIG. 1, and the polishing apparatus 20 shown in FIG. Using this, the wafer 5 was polished. First, the carrier plate was placed on the turntable 7 with the bonding surface of the wafer 5 as one main surface facing up. Next, the turntable 7 was rotated by the rotation control device 9, the mark 3 provided on the carrier plate was detected by the mark detector 6, and the carrier plate was positioned. Thereafter, the wafer 5 was sucked by the suction pad 8 and the adhesive 4 was applied, and then transferred onto the carrier plate and pasted on the pasting surface. Then, the next wafer 5 is pasted by the amount of displacement from the reference position detected by the mark detector 6 determined by the rotation control device 9 in order to secure the pasting portion of the next wafer 5. The table 7 was rotated to attach the next wafer 5 to the next attaching portion, and by repeating this, four wafers 5 were attached to the carrier plate.

  Next, using the polishing apparatus 20, a carrier plate in which the wafer 5 is bonded to the bonding surface which is one main surface via the adhesive 4 is attached to the bonding surface which is one main surface of the carrier plate. The wafer 5 was placed on the wafer polishing platen 14 so that the processing surface of the wafer 5 was opposed to the wafer polishing platen 14, and the support roller 18 supported the side surface of the carrier plate. Next, a rotatable pressing portion 11 was set on the other main surface of the carrier plate. Then, while supplying the polishing liquid 16 from the nozzle 17 onto the wafer polishing platen 14, the wafer polishing platen 14 is rotated by the rotational force transmitted from the power source (not shown) to the rotating shaft 15, thereby supporting the roller 18. The other main surface of the carrier plate was pressed by the pressing portion 11 while being supported by, and the wafer 5 was polished.

  Then, a cycle of polishing the wafer 5 → peeling the wafer 5 with the solvent after polishing → cleaning the carrier plate → attaching the wafer 5 and polishing the wafer 5 was performed for 10 hours a day, and this was performed for one week. The wafer 5 was attached to the carrier plate so that the wafer 5 was at a fixed position every time without changing the displacement from the reference position detected by the mark detector 6.

  As a result, in the conventional carrier plate, a highly accurate wafer 5 with high flatness was obtained from the beginning to the third day, but the flatness of the wafer 5 was lowered after the fourth day, and the last 2 What was polished for one day had a reduction of more than 80% compared to the flatness at the beginning. Then, when this conventional carrier plate was confirmed, the marks 3 provided on the portion extending from the bonding surface of the wafer 5 to the side surface were damaged by a large amount of friction with the support roller 18 when the wafer 5 was polished. Thus, it has been found that there is a problem in the detection of the mark 3 by the mark detector 6.

  On the other hand, the carrier plate 1 according to the present invention has a flatness reduction of less than 10% even after one week, and the wafer 5 can be satisfactorily polished over a long period of time. Was confirmed. Further, when the state of the mark 3 was confirmed after the test was completed, a minute scratch was seen on the mark 3 of the carrier plate 1 of the present invention shown in FIGS. 3 (a) and 3 (b), but still a clear color tone. Further, it was confirmed that the shape was secured and the level could be detected by the mark detector 6 and there was no problem. In addition, with respect to the carrier plate 1 of the example of the present invention shown in FIG.

It is the schematic which shows the example of the wafer sticking apparatus which affixes a wafer on the carrier plate of this invention. 1 shows an example of an embodiment of a polishing apparatus provided with the carrier plate of the present invention as a wafer polishing component, (a) is a schematic cross-sectional view, and (b) is a rotation of a polishing platen and carrier plate of the polishing apparatus. It is the schematic which shows a direction. An example of an embodiment of a carrier plate of the present invention is shown, (a) is a perspective view of a carrier plate having a depression on one main surface side of the side surface with a side surface portion that is flush with the side surface in the circumferential direction, (B) is a perspective view of a carrier plate having a recess on the other main surface side with a second side surface portion that is flush with the side surface in the circumferential direction. The other example of embodiment of the carrier plate of this invention is shown, (a) is a perspective view of the carrier plate in which the surface of a mark is located between the bottom face and side surface of a hollow, (b) is ( It is sectional drawing in the AA 'line in a). It is the schematic which shows the example of the conventional wafer sticking apparatus. An example of a conventional wafer polishing apparatus is shown. (A) is a schematic cross-sectional view, and (b) is a schematic view showing the rotation direction of the polishing platen and carrier plate of the polishing apparatus.

Explanation of symbols

1: Carrier plate 2: Depression 3: Mark 4: Adhesive 5: Wafer 6: Mark detector 7: Turntable 8: Suction pad 9: Rotation control device
10: Wafer pasting equipment
11: Pressing part
12: Cross
13: Rotating table
14: Wafer polishing surface plate
15: Rotation axis
16: Polishing liquid
17: Nozzle
18: Support roller
20: Polishing equipment
30: Pasting surface
31: Side
32: Side part
33: Bottom
34: Second side portion

Claims (7)

It is made of disk-shaped ceramics, has one main surface as a wafer attachment surface, and has a depression on the side surface, with the side surface portion being flush with the side surface in the circumferential direction on the attachment surface side, A carrier plate having a mark having a color tone different from that of the ceramics on a bottom surface of the recess. The carrier plate according to claim 1, further comprising a second side surface portion that is flush with the side surface in the circumferential direction from the depression on the side surface to the other main surface side. The carrier plate according to claim 1 or 2, wherein a surface of the mark is located between a bottom surface and the side surface of the depression. The carrier plate according to any one of claims 1 to 3, wherein the mark is formed by laser light irradiation. The carrier plate according to any one of claims 1 to 3, wherein the mark is made of a plate member having a color tone different from that of the ceramic. 6. The carrier plate according to claim 1, wherein the ceramic is made of any one of alumina, zirconia, cordierite, silicon carbide, silicon nitride, and aluminum nitride. A polishing apparatus comprising the carrier plate according to any one of claims 1 to 6 as a wafer polishing component.

Images