CN107791115A - Processing unit (plant) - Google Patents

Abstract

To provide a processing apparatus capable of forming a desired defect removal layer on a surface to be processed of a wafer without taking time. The processing device (1) has a grinding member (60) for grinding a processed surface of a wafer (W) after grinding and a removal layer forming member (70) for forming a removal layer on the processed surface of the wafer (W). ), the removal layer forming member (70) has: a rotating member (71), which makes the removal wheel (72) forming the removal layer on the processed surface of the wafer (W) rotate together with the rotation member (71); an elevating member (75) that lifts the flaw removal wheel (72) together with the rotating member (71) in a vertical direction relative to the holding surface (3a) of the holding table (3); and a horizontal moving member (76), It makes the defect removal wheel (72) move in the horizontal direction with the rotating member (71) relative to the holding surface (3a) of the holding table (3), so it can be removed by using the grinding member (60) as a different mechanism. A defect layer forming member (70) forms a defect layer on a processed surface of a wafer (W) in a short time.

Description

Processing device

technical field

The present invention relates to a processing device which processes a wafer and forms a desired defect removal layer on a processed surface of the wafer.

Background technique

When using a grinding tool to grind a wafer to make it thinner, the bending strength of the chip will be reduced due to processing strain and the like on the processed surface of the wafer, so after the wafer is ground, do not use The surface to be processed of the wafer is polished by dry polishing of dry polishing or a chemical mechanical polishing method called CMP (Chemical Mechanical Polishing) to remove processing strain.

Here, in the wafer from which the processing strain has been removed, there arises a problem that the removal effect of trapping the metal impurities which cause the metal contamination of the device is lost. Therefore, as a processing apparatus for forming a removal layer having a removal effect on a wafer, there is, for example, a processing apparatus disclosed in Patent Document 1 below. In this processing device, after the wafer has been ground, the polishing member is used to perform polishing using CMP, and then the slurry is switched to pure water to supply pure water between the back surface of the wafer and the polishing surface of the polishing pad. The water forms a defect removal layer on the backside of the wafer.

Patent Document 1: Japanese Patent No. 5916513

However, in order to form the removal layer on the back surface of the wafer in order to switch between the slurry and the pure water in the above-mentioned processing apparatus, it is necessary to achieve a state in which the slurry does not adhere to the polishing pad at all. That is, in the state where the slurry adheres to the polishing pad, a desired defect removal layer cannot be formed on the back surface of the wafer, and the polishing pad needs to be cleaned or the like. Therefore, there is a problem that it takes time to form the removal layer although the grinding/polishing of the wafer has been completed.

Contents of the invention

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a processing device capable of forming a desired defect removal layer on a surface to be processed of a wafer without taking time.

The present invention is a processing device for forming a defect-removing layer on the processed surface of a wafer after grinding and grinding, wherein the processing device has: a rotating table configured to be able to center Rotating on its own axis, the rotary table positions wafer pairs in the loading and unloading area for loading and unloading wafers, the grinding area for grinding wafers, and the grinding area for grinding wafers; holding the table, it works with this rotation The center of the table is arranged equiangularly, and has a holding surface for holding the wafer; a transport member, which carries the wafer in and out relative to the holding table positioned in the loading and unloading area; and a grinding member, which grinding the wafer held by the holding table positioned in the grinding area to form the wafer into a predetermined thickness; and a grinding member for grinding the processed surface of the wafer held by the holding table positioned in the grinding area and a defect layer forming member, which forms a defect layer on the processed surface of the wafer held by the holding table positioned in the loading and unloading area, and the defect layer forming member has: a rotating member, which has a mounting seat The center of the axis is the main shaft that rotates, wherein a disc-shaped blemish pad is installed on the mounting seat; and a lifting member that makes the rotating member move up and down in a vertical direction relative to the holding surface of the holding table .

In addition, the processing apparatus may be configured to include a horizontal movement member that moves the rotation member in the horizontal direction with respect to the holding surface of the holding table.

The processing device of the present invention has: a rotating table configured to be able to rotate around the center to position wafers in the loading and unloading area, the grinding area, and the grinding area; Arranged at an equal angle at the center, it has a holding surface for holding the wafer; a transport member, which carries the wafer in and out relative to the holding table positioned in the loading and unloading area; a grinding member, which is positioned in the grinding area The wafer held by the holding table of the invention is ground to form the wafer into a predetermined thickness; the grinding member grinds the processed surface of the wafer held by the holding table positioned in the grinding area; and the removal layer forming member The removal layer is formed on the surface to be processed of the wafer held by the holding table positioned in the loading and unloading area. A disc-shaped defect removal pad is installed on the mounting base; and an elevating member, which makes the rotating member vertically elevate relative to the holding surface of the holding table, so that after the wafer is ground/polished, the rotating By rotating the table and positioning the holding table in the loading and unloading area, the removal layer can be formed on the surface to be processed of the wafer by the removal layer forming member which is a different mechanism from the polishing member without taking time.

In the case where there is a horizontal moving member for moving the rotating member in the horizontal direction relative to the holding surface of the holding table, the removal layer forming member can be positioned so as not to interfere with the relative positioning of the wafer in the loading and unloading area. The position where the above-mentioned holding table carries out loading and unloading, similar to the above, can form a defect removal layer on the surface to be processed of the wafer without taking time.

Description of drawings

FIG. 1 is a perspective view showing the structure of a processing device.

Fig. 2 is a perspective view showing the structure of a grinding member.

Fig. 3 is a perspective view showing the structure of a removal layer forming member.

4 is a cross-sectional view showing a state where a removal layer is formed on a surface to be processed of a wafer by a removal layer forming member.

Label description

1: processing device; 2: rotating table; 3: holding table; 4: partition board; 5a, 5b: box; 6: loading and unloading components; 7: moving components in X direction; 8: temporarily placing components; 9: Cleaning component; 10: Transport component; 11: Adsorption pad; 12: Arm; 13: Support rod; 14: Moving block; 15: Support column; 16: Guide rail; 20: Rough grinding component; 21: Main shaft; 22: Spindle housing; 23: electric motor; 24: rough grinding wheel; 25: grinding tool; 30: rough grinding feed member; 31: ball screw; 32: electric motor; 33: guide rail; 34: lifting plate; 340 : guide groove; 40: fine grinding member; 41: main shaft; 42: main shaft housing; 43: motor; 44: rough grinding wheel; 45: grinding tool; 50: fine grinding feed member; 51: ball Lead screw; 52: motor; 53: guide rail; 54: lifting plate; 540: guide slot; 60: grinding member; 61: rotating member; 610: main shaft; 611: motor; 612: main shaft shell; 613: guide slot; 62 : grinding wheel; 620: mounting base; 621: abutment; 622: grinding pad; 63: movable block; 630: guide rail; 631: guide groove; 64: fixed block; 640: guide rail; 65: first grinding feed Component; 650: motor; 66: second grinding feed component; 660: motor; 70: defect layer forming component; 71: rotating component; 710: spindle; 711: motor; 712: spindle housing; 713: guide groove; 72: Defect wheel; 720: Mounting seat; 721: Abutment; 722: Defect pad; 73: Movable block; 730: Guide rail; 731: Guide groove; 74: Fixed block; 740: Guide rail; 741: Guide groove 75: lifting member; 750: electric motor; 76: horizontal moving member; 760: ball screw; 761: electric motor; 80: trimming unit; 81: bracket; 82: trimming part;

Detailed ways

The processing apparatus 1 shown in FIG. 1 is an example of the processing apparatus which grinds/polishes the wafer which is a to-be-processed object. The processing device 1 has a device base 100 extending in the Y-axis direction and an upright wall 101 erected at the rear of the device base 100 in the Y-axis direction. The processing apparatus 1 shown in this embodiment has: a loading and unloading area P1 for loading and unloading wafers; a rough grinding area P2 for rough grinding wafers before processing; and a finishing grinding area P3 for It is used for fine grinding the wafer after rough grinding; and the grinding area P4 is used for grinding the wafer after fine grinding.

At the center of the upper surface of the device base 100 is arranged a rotary table 2 capable of rotating about the center, and a holding table 3 for holding a wafer is arranged on the rotary table 2 . At least four holding tables 3 are arranged at equal angular intervals on the rotary table 2 around the center of the rotary table 2 . A partition plate 4 is provided on the upper surface of the rotary table 2 for partitioning the area where the respective holding tables 3 are provided. The height of the partition plate 4 is higher than that of the holding table 3 . Then, by rotating the rotary table 2 and revolving the holding table 3 , the holding table 3 can be sequentially positioned in the loading/unloading area P1 , the rough grinding area P2 , the finish grinding area P3 , and the grinding area P4 .

Stages 102 a and 102 b are arranged adjacent to each other at the front of the device base 100 in the Y-axis direction. A cassette 5a for storing wafers before grinding is arranged on stage 102a, and a cassette 5b for storing wafers after grinding is arranged on stage 102b. Arranged near the cassette 5a and the cassette 5b is a loading/unloading member 6 that unloads unprocessed wafers from the cassette 5a and loads processed wafers into the cassette 5b. The loading and unloading member 6 is connected to the X-axis direction moving member 7 . In addition, the loading/unloading member 6 can be horizontally moved in the X-axis direction by the X-axis direction moving member 7 , whereby the loading/unloading member 6 can be positioned at a position facing the cassette 5 a or the cassette 5 b.

In the vicinity of the loading/unloading area P1, a temporary storage unit 8 is disposed, and the temporary storage unit 8 is used to temporarily store wafers before processing and perform center alignment. A cleaning member 9 for cleaning processed wafers is provided at a position adjacent to the temporary storage member 8 .

The processing apparatus 1 has: a transport member 10 for carrying in and out a wafer from the holding table 3 positioned in the carrying-in/out area P1; The held wafer is roughly ground to a prescribed thickness; the rough grinding feeding member 30 performs grinding feeding of the rough grinding member 20 in the vertical direction (Z-axis direction) relative to the holding table 3; the fine grinding grinding member 40, which will finish grinding the wafer held by the holding table 3 positioned in the finishing grinding area P3 to a prescribed finished thickness; Grinding feeding is carried out with respect to the holding table 3; the grinding member 60, which grinds the processed surface of the wafer held by the holding table 3 positioned at the grinding area P4; and the removal layer forming member 70, which is A removal layer is formed on the surface to be processed of the wafer held by the holding table positioned in the loading/unloading area P1.

The transport member 10 has: a disk-shaped adsorption pad 11 for adsorbing a wafer; an arm portion 12 for supporting the adsorption pad 11; a support rod 13 for supporting the arm portion 12; a pair of support columns 15 for Installed on the device base 100; guide rail 16, which is fixed on the upper ends of a pair of support columns 15, extending in the Y-axis direction; Move back and forth in the direction. The support rod 13 can be raised and lowered in the Z-axis direction by a not-shown raising and lowering mechanism. The transfer member 10 thus constituted can transfer the unprocessed wafer temporarily placed on the temporary transfer member 8 to the holding table 3 positioned in the loading/unloading area P1, and can transfer the processed wafer from the loading/unloading area P to the holding table 3. The holding table 3 is carried out and transported to the cleaning member 9.

The rough grinding member 20 is arranged on the side of the upright wall 101 via the rough grinding feeding member 30 and is arranged in the rough grinding area P2. The rough grinding member 20 has: a main shaft 21 having an axis in the Z-axis direction; a main shaft housing 22 which supports the main shaft 21 in a rotatable manner; a motor 23 connected to the upper end of the main shaft 21; and a rough grinding wheel 24 which Installed on the lower end of the main shaft 21 ; Then, the main shaft 21 is rotated by the motor 23, so that the rough grinding wheel 24 can be rotated at a predetermined rotation speed.

The rough grinding feed member 30 has: a ball screw 31 extending in the Z-axis direction; a motor 32 connected to one end of the ball screw 31; a pair of guide rails 33 extending parallel to the ball screw 31; One surface of the plate 34 is connected to the rough grinding member 20 . A pair of guide grooves 340 formed on the other surface of the lift plate 34 are slidably connected to the guide rail 33 , and a nut formed at the center of the lift plate 34 is screwed to the ball screw 31 . By rotating the ball screw 31 by the motor 32 , the rough grinding member 20 can be raised and lowered in the Z-axis direction along the pair of guide rails 33 together with the lifting plate 34 .

The finishing member 40 is arranged on the side of the upright wall 101 via the finishing feeding member 50, and is arranged in the finishing area P3. The fine grinding member 40 has: a main shaft 41 having an axis in the Z-axis direction; a main shaft housing 42 which rotatably supports the main shaft 41; a motor 43 connected to the upper end of the main shaft 41; and a fine grinding wheel 44 which Installed on the lower end of the main shaft 41 ; and a grinding tool 45 for fine grinding, which is fixedly installed on the bottom of the fine grinding wheel 44 in a ring shape. By rotating the main shaft 41 with the motor 43, the finish grinding wheel 44 can be rotated at a predetermined rotation speed.

The finishing feeding member 50 has: a ball screw 51 extending in the Z-axis direction; a motor 52 connected to one end of the ball screw 51; a pair of guide rails 53 extending parallel to the ball screw 51; One surface of the plate 54 is connected to the fine grinding member 40 . A pair of guide grooves 540 formed on the other surface of the lift plate 54 are slidably connected to the guide rail 53 , and a nut formed at the center of the lift plate 54 is screwed to the ball screw 51 . By rotating the ball screw 51 by the motor 52 , the finishing member 40 can be moved up and down in the Z-axis direction along the pair of guide rails 53 together with the lifting plate 54 .

The polishing member 60 is arranged on the device base 100 as indicated by the dashed-two dotted line, and is arranged in the polishing region P4. As shown in FIG. 2, the grinding member 60 has: a grinding wheel 62, which grinds the surface to be processed of the wafer; a rotating member 61, which rotates the grinding wheel 62; and a movable block 63, which supports the rotating member 61 so as to be able to Lifting and lowering in the Z-axis direction; the first grinding feed member 65, which is arranged on the movable block 63, makes the rotating member 61 move up and down in the Z-axis direction; the fixed block 64, which supports the movable block 63 as Can move on the X-axis direction; And the 2nd grinding feeding member 66, it is arranged on the fixed block 64, makes the movable block 63 move in the X-axis direction parallel to the holding surface 3a of the holding table 3. move.

The rotating member 61 has: a main shaft 610 having an axis in the Z-axis direction; a motor 611 connected to an upper end of the main shaft 610 ; and a main shaft case 612 rotatably supporting the main shaft 610 . The grinding wheel 62 has: a base 621 detachably attached to the lower end of the main shaft 610 via a mount 620 ; and a disc-shaped polishing pad 622 attached to the lower portion of the base 621 . Further, the rotating member 61 drives the motor 611 so that the polishing pad 622 can be rotated at a predetermined rotation speed about the center of the mounting base 620 as an axis.

The polishing pad 622 is composed of, for example, a polishing pad obtained by dispersing abrasive grains in polyurethane foam or nonwoven fabric and fixing them with an appropriate bonding material. As the abrasive grains, for example, GC (Green Carbide: green silicon carbide) abrasive grains having a particle diameter of 0.2 to 1.5 μm can be used. In addition, the abrasive grains may be abrasive grains that are harder than the wafer and capable of causing minute scratches on the surface to be processed of the wafer. As abrasive grains, abrasive grains such as diamond, alumina, ceria, and CBN may be used in addition to GC abrasive grains. When the polishing process using CMP is performed by the polishing member 60, although not shown in the figure, a slurry for supplying the slurry is connected between the polishing pad 622 and the processed surface of the wafer held by the holding table 3. Provide source. In addition, as the slurry, an alkaline polishing liquid is often used, but an acidic polishing liquid may be used depending on the material of the wafer to be processed. In addition, dry grinding (dry polishing) may be performed using the grinding member 60 .

The first grinding feed member 65 includes: a ball screw (not shown) extending in the Z-axis direction; and a motor 650 connected to one end of the ball screw. A pair of guide rails 630 extending along the Z-axis direction are formed on the side of the movable block 63, and a pair of guide grooves 613 formed in the main shaft housing 612 are slidably connected with the pair of guide rails 630. The nut formed in the center of the main shaft housing 612 and the Ball screw threaded. Furthermore, by rotating the ball screw with the motor 650 , the grinding wheel 62 can be moved in the Z-axis direction along with the rotating member 61 along the pair of guide rails 630 .

The second grinding feed member 66 has a ball screw (not shown) extending in the X-axis direction, and a motor 660 connected to one end of the ball screw. A pair of guide rails 640 extending along the X-axis direction are formed on the side of the fixed block 64 , a pair of guide grooves 631 formed in the movable block 63 are slidably connected with the pair of guide rails 640 , and a nut formed in the center of the movable block 63 Screwed with ball screw. Furthermore, by rotating the ball screw with the motor 660 , the movable block 63 can be moved in the X-axis direction along the pair of guide rails 640 .

The removal layer formation member 70 shown in FIG. 1 is arrange|positioned in the vicinity of the polishing member 60, and is arrange|positioned in the carrying-in and carrying-out area|region P1. As shown in Figure 3, the defect-removing layer forming member 70 has: a defect-removing wheel 72, which forms a defect-removing layer on the surface to be processed of the wafer; a rotating member 71, which rotates the defect-removing wheel 72; a movable block 73, It supports the rotating member 71 so as to be able to move up and down in the Z-axis direction; the lifting member 75 makes the rotating member 71 move in the vertical direction (Z-axis direction) with respect to the holding surface 3a of the holding table 3 shown in FIG. 1 . lift; fixed block 74, which supports movable block 73 so as to be movable in the Y-axis direction; and horizontal movement member 76, which is arranged on fixed block 74, so that movable block 73 can hold The holding surface 3a moves in the horizontal direction (Y-axis direction).

The rotating member 71 has a main shaft 710 having an axis in the Z-axis direction, a motor 711 connected to the upper end of the main shaft 710 , and a main shaft housing 712 rotatably supporting the main shaft 710 . The defect removal wheel 72 has: a base 721 detachably mounted on the lower end of the main shaft 710 via a mount 720 ; In addition, the removal layer forming member 70 drives the motor 711 so that the removal pad 722 can be rotated at a predetermined rotation speed about the center of the attachment seat 720 as an axis.

The diameter of the removing pad 722 is, for example, not less than the radius and not more than the diameter of the holding surface 3 a of the holding table 3 shown in FIG. 1 . The defect removal pad 722 is the same as the above-mentioned polishing pad 622. It is formed by dispersing abrasive grains such as GC, diamond, aluminum oxide, cerium oxide, and CBN in foamed polyurethane or non-woven fabric, and fixing them with suitable bonding materials. Got it. As for the abrasive grains, abrasive grains having a particle diameter smaller than that of the abrasive grains dispersed in the polishing pad 622 are used. As shown in FIG. 4 , the removal layer forming member 70 is connected to a pure water supply source 90 . The pure water supply source 90 is configured to supply pure water at a predetermined flow rate from the center of the remover pad 722 to the portion of the wafer in contact with the remover pad 722 . In addition, depending on the defect removal layer to be formed, the particle diameter of the abrasive grains dispersed in the defect removal pad 722 may be larger than the particle diameter of the abrasive grains dispersed in the polishing pad 622 .

The elevating member 75 shown in FIG. 3 includes: a ball screw (not shown) extending in the Z-axis direction; and a motor 750 connected to one end of the ball screw. A pair of guide rails 730 extending along the Z-axis direction are formed on the side surface 73a of the movable block 73. A pair of guide grooves 713 formed in the main shaft housing 712 are slidably connected to the pair of guide rails 730. The nut and the ball at the center of the main shaft housing 712 The lead screw is screwed together. Furthermore, by rotating the ball screw with the motor 750, the defect removal wheel 72 can be raised and lowered in the Z-axis direction along the pair of guide rails 730 together with the rotating member 71.

The horizontal moving member 76 has: a ball screw 760 extending in the Y-axis direction; and a motor 761 connected to one end of the ball screw 760 . A pair of guide rails 740 extending along the Y-axis direction are formed on the side 74a of the fixed block 74, and a pair of guide grooves 731 formed in the movable block 73 are slidably connected with the pair of guide rails 740. The nut at the center of the movable block 73 Screwed with the ball screw 760. By rotating the ball screw 760 by the motor 761 , the movable block 73 can be moved horizontally in the Y-axis direction along the pair of guide rails 740 , and the defect removal wheel 72 can be moved horizontally in the Y-axis direction together with the rotating member 71 . The fixed block 74 shown in this embodiment has a structure extending to a position protruding to the outside of the rotary table 2 shown in FIG. 1 . Therefore, when the wafer is carried in and out with respect to the holding table 3 positioned in the loading and unloading area P1, the movable block 73 is moved from the loading and unloading area P1 by the horizontal movement member 76 to, for example, retreating toward the −Y direction side. The location can prevent the removal layer forming member 70 from interfering with the loading and unloading of the wafer relative to the holding table 3 positioned in the loading and unloading area P1.

Furthermore, as shown in FIG. 3 , in the removal layer forming member 70 , a dressing unit 80 for dressing (sawing and shaping) the removal pad 722 is disposed below the removal wheel 72 . The trimming unit 80 has a bracket 81 fixed to the side surface 74 a of the fixed block 74 , and a trimming member 82 arranged above the bracket 81 . And, when using the trimming unit 80 to trim the defect removal pad 722, after the defect removal pad 722 is positioned at a height in contact with the trimming member 82 by the lifting member 75 while the defect removal wheel 72 is rotated by the rotating member 71, The blemish removal pad 722 is moved horizontally by the horizontal movement member 76 , and the blemish removal pad 722 is scraped by the trimming member 82 to perform trimming.

Next, an example of the operation of the processing device 1 will be described in detail. The wafer W shown in FIG. 4 as a processing object is an example of a workpiece, and is not particularly limited. Examples of the wafer W include Si wafers, GaN wafers, SiC wafers, and the like. A plurality of devices are formed on the front surface Wa of the wafer W, which becomes a held surface held on the holding table 3 . A protective member is pasted on this front Wa in advance. On the other hand, the back surface Wb on the opposite side to the front surface Wa of the wafer W is ground/polished and is a processed surface on which a defect removal layer is formed. A plurality of unprocessed wafers W are accommodated in the cassette 5 a shown in FIG. 1 .

First, the loading/unloading unit 6 takes out one unprocessed wafer W from the cassette 5a, and the loading/unloading unit 6 is moved, for example, in the −X direction by the X-axis direction moving unit 7 to temporarily place the wafer W on the temporary placement unit 8 . Next, the transfer means 10 adsorbs the wafer W centered on the temporary placement means 8 by the suction pads 11, and transfers the wafer W to the holding table 3 on standby in the loading/unloading area P1. At this time, the removal layer forming member 70 is moved along the fixed block 74 in, for example, the −Y direction, and retracted to a retracted position where the wafer W is not hindered from being carried into the holding table 3 . The holding table 3 suction-holds the wafer W by using the holding surface 3a, and the suction force of the suction source acts on the holding surface 3a.

Next, the rotary table 2 rotates, for example, in the direction of the arrow A, and aligns the wafer W in the rough grinding area P2 while rotating the holding table 3 located in the loading/unloading area P1. The rough grinding feeding member 30 drives the ball screw 31 by the motor 32 to lower the rough grinding member 20 in the −Z direction toward the wafer W held on the holding table 3 . The rough grinding member 20 presses the wafer W with the grinding stone 25 while rotating the main shaft 21 and rough grinds the wafer W until the wafer W reaches a desired thickness. When the wafer W reaches a desired thickness, the rough grinding feed member 30 raises the rough grinding member 20 in the +Z direction, and the rough grinding ends.

After the rough grinding is completed, the rotary table 2 is then rotated in the direction of the arrow A, and the rough-ground wafer W is aligned in the finish-grinding area P3. The finish grinding feeding member 50 drives the ball screw 51 by the motor 52 to lower the finish grinding member 40 in the −Z direction toward the wafer W held on the holding table 3 . The finish grinding member 40 presses the wafer W with the grinding stone 45 while rotating the spindle 41 to finish grind the wafer W until the wafer W reaches a finished thickness. When the wafer W reaches the finished thickness, the finish grinding member 40 is raised in the +Z direction by the finish grinding feeding member 50, and the finish grinding is completed.

After finish grinding is completed, the rotary table 2 is then rotated in the direction of the arrow A to align the finish-ground wafer W in the grinding area P4. In the grinding member 60 shown in FIG. 2 , the grinding wheel 62 is lowered together with the spindle housing 612 by the first grinding feeding member 65 while the spindle 610 is rotated to rotate the grinding pad 622 at a predetermined rotation speed. The rotating polishing pad 622 is brought into contact with the entire surface of the wafer W held on the holding table 3, and the movable block 63 is reciprocated in the X-axis direction by the second polishing and feeding member 66, whereby the rotating polishing pad 622 The polishing pad 622 slides against the wafer W to polish the wafer W. As shown in FIG. During polishing of the wafer W, the slurry is supplied from the slurry supply source between the rotating wafer W and the polishing pad 622, thereby combining the chemical action of the slurry with the mechanical action of the polishing pad 622, The processing strain generated on the processed surface of the wafer W during grinding is removed.

After the polishing is completed, the rotary table 2 is then rotated in the direction of the arrow A to align the polished wafer W in the loading/unloading area P1. What is necessary is just to move the removal layer forming member 70 along the fixed block 74, for example, +Y direction, and to move from the above-mentioned retracted position to the loading/unloading area P1 at least before starting the removal layer formation. When forming a defect removal layer on the surface to be processed of the wafer W, as shown in FIG. While rotating at a predetermined rotation speed, for example, in the direction of arrow B, the defect removal wheel 72 is lowered together with the main shaft housing 712 by the elevating member 75 shown in FIG. 3 . The removal pad 722 is brought into contact with the back surface Wb of the wafer W held on the holding table 3, and the movable block 73 is reciprocated in the Y-axis direction by the horizontal movement member 76 shown in FIG. The defect pad 722 slides against the wafer W to form a defect removal layer on the back surface Wb of the wafer W.

At this time, pure water is supplied from the center of the removal pad 722 to the contact surface between the removal pad 722 and the wafer W through the pure water supply source 90 . That is, by introducing pure water between the back surface Wb of the rotating wafer W and the polishing surface of the removal pad 722, a damage layer consisting of fine scratches is formed on the back surface Wb of the wafer W. This damaged layer functions as a defect-removal layer that produces a defect-removal effect. In this way, the rear surface Wb of the ground/polished wafer W is ground by the removal layer forming member 70 different from the grinding member 60 to form a removal layer on the rear surface Wb. In addition, in the present embodiment, pure water is used to form the defect-removing layer, but other than pure water, a chemical solution for neutralizing the slurry used at the time of polishing may be used. That is, it is only necessary to provide an acidic chemical solution for neutralization when the alkaline slurry is used for grinding. The chemical liquid for neutralizing the slurry is preferably a liquid that does not react with silicon.

After the removal layer is formed, the removal layer forming member 70 shown in FIG. 1 is moved from the loading/unloading area P1 to the retracted position described above. Next, the transfer member 10 adsorbs the processed wafer W held on the holding table 3 located in the loading/unloading area P1 by the suction pad 11 , and transfers the wafer W to the cleaning member 9 . After the cleaning/drying process is performed on the wafer W by the cleaning member 9 , the wafer W is taken out from the cleaning member 9 by the loading and unloading member 6 and stored in the cassette 5 b. In this way, the grinding, polishing, and formation of the removal layer for one wafer W are completed. Then, the same processing as above is repeatedly performed on a plurality of wafers W. As shown in FIG.

When the removal layer forming member 70 is used to continuously form the removal layer on a plurality of wafers W, the removal pad 722 becomes dull or wears out, so in the processing apparatus 1, the trimming unit 80 shown in FIG. 3 is used. The blemish removal pad 722 is trimmed. Specifically, the movable block 73 is moved in the X-axis direction by the horizontal moving member 76 shown in FIG. 3 to position the blemish removal wheel 72 above the trimming member 82 . Then, while the main shaft 710 is rotated by the rotating member 71 so that the defect removal wheel 72 is rotated, the defect removal pad 722 is lowered by the lifting member 75 and the rotating defect removal pad 722 is pushed against the trimming member 82 against the defect removal pad. 722 carries out scraping, thereby the grinding surface of blemish removal pad 722 is finished. In addition, the timing of dressing the blemish-removing pad 722 is not particularly limited, and the state of the blemish-removing pad 722 may be constantly monitored to perform appropriate dressing, or may be regularly trimmed.

In this way, the processing device 1 of the present invention has: a rotary table 2, which is arranged so as to be able to rotate around the center, and moves along the loading and unloading area P1, the rough grinding area P2, the fine grinding area P3, and the grinding area. P4 rotates; the holding table 3 is arranged equiangularly around the center of the rotating table 2, and has a holding surface 3a for holding the wafer W; The holding table 3 carries the wafer W in and out; the rough grinding member 20 roughly grinds the wafer W held by the holding table 3 positioned in the rough grinding area P2 to a predetermined thickness; the fine grinding member 40 , which finish grinds the wafer W held by the holding table 3 located in the fine grinding area P3 to the finished thickness; the grinding member 60, which is positioned at the grinding area P4 The wafer W held by the holding table 3 is The processed surface is ground; and the defect-removing layer forming member 70 forms a defect-removing layer on the processed surface of the wafer W held by the holding table 3 positioned at the loading and unloading area P1, and the defect-removing layer forming member 70 has: Defect wheel 72, which forms a defect removal layer on the surface to be processed of the wafer W; rotating member 71, which makes the defect removal wheel 72 rotate; lifting member 75, which makes the defect removal wheel 72 work with the rotation member 71 relative to the maintenance The holding surface 3a of the table 3 is raised and lowered in the vertical direction (Z axis direction); axis direction), so after the wafer W has been ground/polished, the removal layer forming member 70, which is a different mechanism from the grinding member 60, can be used to form a desired surface on the processed surface of the wafer W in a short time. Defect layer.

The case where the removal layer forming member 70 shown in this embodiment has a wet type removal pad 722 using pure water has been described, but it is not limited to this structure, and the removal layer forming member 70 may also use a dry type. The removal pad forms a removal layer on the backside Wb of the wafer W. In this case, it is preferable to use a cover that covers the dry type removal pad and the holding table so as to prevent the scattering of dust generated when the removal layer is formed on the surface of the wafer W to be processed by the removal pad.

Although the processing apparatus 1 shown in this embodiment has demonstrated the case where the horizontal movement member 76 is provided in the defect-removing layer formation member 70, it is not limited to this structure, The structure which does not have the horizontal movement member 76 is also possible. In this case, it is preferable that the trimming unit 80 itself is configured to be movable in the horizontal direction (Y-axis direction) with respect to the blemish removal pad 722 .

Claims (2)

1. A processing device which, after performing grinding and polishing on a processed surface of a wafer, forms a defect removal layer on the processed surface, wherein, The processing unit has: The rotary table is arranged so as to be able to rotate around the center, and the rotary table places wafer pairs in a loading and unloading area for loading and unloading wafers, a grinding area for grinding wafers, and a grinding area for grinding wafers. grinding area; a holding table, which is arranged equiangularly around the center of the rotating table, and has a holding surface for holding the wafer; a transport member for carrying wafers in and out with respect to the holding table positioned in the loading and unloading area; a grinding member for grinding the wafer held by the holding table positioned in the grinding area to form the wafer into a predetermined thickness; a grinding member, which grinds the processed surface of the wafer held by the holding table positioned in the grinding area; and a removal layer forming member for forming a removal layer on the surface to be processed of the wafer held by the holding table positioned in the loading and unloading area, The removal layer forming member has: a rotating member having a main shaft that rotates about the center of a mounting seat on which a disk-shaped blemish removal pad is mounted; and and a lifting member for vertically lifting the rotating member relative to the holding surface of the holding table. 2. The processing device according to claim 1, wherein, The processing device has a horizontal moving member that moves the rotating member in a horizontal direction relative to the holding surface of the holding table.