JP2010225936A - Method and device for processing substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and device for processing a substrate capable of thinning a silicon substrate while preventing a surface of the silicon substrate from being roughened. <P>SOLUTION: In a grinding process (refer to fig. (b)), the back face of a wafer W is ground by a grinding wheel of a grinding device 80. The grinding wheel is worn along with progress of the grinding of the wafer W, and a binder fractured from the grinding wheel may adhere to the back face of the wafer W. Thereafter, a UV irradiation process is executed. In the UV irradiation process (refer to fig. (c)), the back face of the wafer W is irradiated with an ultraviolet ray from an ultraviolet lamp 32. Even when an organic adhesive substance adheres to the back face of the wafer W, the internal bond of the organic adhesive substance is cut by the irradiation of the ultraviolet ray, and the organic adhesive substance is destroyed at a molecular level. Thereafter a hydrofluoric-nitric acid supply process (refer to fig. (d)) is executed, and the back face of the wafer W is etched using hydrofluoric-nitric acid. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a substrate processing method and a substrate processing apparatus for performing a thinning process on a silicon substrate such as a silicon wafer.

  In a semiconductor device manufacturing process, a liquid process using a processing liquid is performed on a silicon wafer. One of such liquid processes is an etching process performed by supplying an etching liquid to one surface of a silicon wafer. It is known that the silicon wafer is thinned by such an etching process. Specifically, by supplying a fluoric acid nitric acid mixture with extremely high etching power to the back surface of the silicon wafer (the back surface opposite to the surface on the device formation area side), the wafer material is made uniform from the surface layer on the back surface. Can be removed by etching (see, for example, Patent Document 1). In such thinning of a silicon wafer, for example, the thickness of a silicon wafer of 725 μm is generally reduced to about 40 μm.

  Also known is a method of thinning the silicon wafer by grinding the back surface of the silicon wafer. In this grinding process, the back surface of the silicon wafer is ground flat by bringing the grinding wheel rotated at high speed into contact with the back surface of the silicon wafer.

JP 2007-88381 A

  The inventors of the present application are considering performing a grinding process on the back surface of a silicon wafer prior to an etching process using a hydrofluoric acid nitric acid mixed solution. That is, after the silicon wafer is thinned to a predetermined thickness by a grinding process, it is further thinned by an etching process. Since the grinding process has a higher thinning rate than the etching process, the efficiency of the process can be improved as compared with the case where the thinning is performed only by the etching process.

  However, when the back surface of the silicon wafer is ground, and then the back surface is etched with a hydrofluoric acid / nitric acid mixture, the back surface of the silicon wafer after the etching process has scratches, irregularities (etch pits), haze, etc. Roughness may occur. If the back surface of the silicon wafer after the thinning process is rough, the semiconductor device may be damaged in the subsequent processes and mounting.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a substrate processing method and a substrate processing apparatus capable of thinning a silicon substrate while preventing surface roughness of the silicon substrate.

  The invention according to claim 1 for achieving the above object includes a grinding step (S3) of grinding the silicon substrate (W) using a grinding wheel (85), and the silicon substrate after execution of the grinding step. Organic deposit removal step (S6) for removing organic deposits generated in the grinding step, and supply of hydrofluoric acid and nitric acid mixture to one surface of the silicon substrate after the organic deposit removal step A substrate processing method including a step (S9).

In addition, the alphanumeric characters in parentheses represent corresponding components in the embodiments described later. The same applies hereinafter.
In the grinding process, one surface of the silicon substrate is ground by a grinding wheel. The grinding wheel is formed, for example, by hardening abrasive grains (86) with a resin binder (B). In the grinding process, the resin binder contained in the grinding wheel is crushed and dispersed around. When the crushed resin binder adheres to one side of the silicon substrate and becomes an organic deposit, this organic deposit functions as an etching mask in the subsequent hydrofluoric acid / nitric acid mixture supply step, and the hydrofluoric acid / nitric acid mixture There is a risk of hindering etching. For this reason, surface roughness may occur on one surface of the silicon substrate.

  According to the method of the present invention, the organic deposit removal step is performed prior to the hydrofluoric acid nitric acid mixture supply step. In the organic deposit removing process, the organic deposit generated in the grinding process is removed from the silicon substrate. Then, since the hydrofluoric acid / nitric acid mixture supplying step is performed after the organic deposit is removed, the etching of the one surface of the silicon substrate by the hydrofluoric acid / nitric acid mixture is not hindered by the organic deposit. Thereby, the silicon substrate can be thinned while preventing or suppressing the occurrence of surface roughness on one surface of the silicon substrate.

In this specification, “removing organic deposits” means removing organic deposits from the substrate surface, destroying organic deposits at the molecular level, or removing organic deposits partially. This is intended to include downsizing.
Further, the “hydrofluoric acid nitric acid mixed solution” is intended to include not only a mixed solution of hydrofluoric acid and nitric acid but also a mixture of hydrofluoric acid and nitric acid with another acid such as phosphoric acid.
The method according to claim 2, wherein, prior to the grinding step, a reinforcing substrate (S) for reinforcing the silicon substrate is disposed on the other surface opposite to the one surface of the silicon substrate via an adhesive (A). It is a substrate processing method of Claim 1 which further includes the bonding process (S1) bonded together.

According to the method of the present invention, the reinforcing substrate is bonded to the other surface of the silicon substrate. When the silicon substrate and the reinforcing substrate are bonded together, the silicon substrate is reinforced by the reinforcing substrate and hardly deforms.
A grinding process is performed on the reinforced silicon substrate. In the grinding process in which the silicon substrate is ground by the grinding wheel, a relatively large force acts on the silicon substrate. However, since the silicon substrate is reinforced, deformation of the silicon substrate in the grinding process can be prevented.

In the bonding step, for example, the reinforcing substrate is bonded to the silicon substrate via a resin adhesive. Therefore, when the adhesive protrudes from between the silicon substrate and the reinforcing substrate, the adhesive may be crushed by the grinding wheel and dispersed to the periphery, and may adhere to one surface of the silicon substrate as an organic deposit.
According to the method of the present invention, even if an adhesive adheres to the one surface of the silicon substrate as an organic deposit in the grinding process, the adhesive is removed prior to the execution of the hydrofluoric acid / nitric acid mixture supplying process. The For this reason, the etching to the one surface of the silicon substrate by the hydrofluoric acid nitric acid mixed solution is not hindered by the adhesive.

According to a third aspect of the present invention, the organic deposit removing step may include an ultraviolet irradiation step (S6) for irradiating the silicon substrate with ultraviolet rays. According to this method, by irradiating the silicon substrate with ultraviolet rays, the internal bond of the organic deposit adhering to one surface of the silicon substrate can be cut, and the organic deposit can be destroyed at the molecular level.
According to a fourth aspect of the present invention, the organic deposit removal step may include an ozone gas supply step of supplying ozone gas to the silicon substrate. According to this method, by supplying ozone gas to the silicon substrate, it is possible to oxidize organic deposits adhering to one surface of the silicon substrate and destroy the organic deposits at the molecular level.

According to a fifth aspect of the present invention, the organic deposit removing step may include a sulfuric acid hydrogen peroxide solution supplying step for supplying a sulfuric acid hydrogen peroxide solution mixed solution to the silicon substrate. According to this method, by supplying a mixed solution of sulfuric acid and hydrogen peroxide to a silicon substrate, organic deposits adhering to one surface of the silicon substrate are converted to peroxomonosulfuric acid ( It can be peeled off by the strong oxidizing power of H ₂ SO ₅ ).

In addition, as described in claim 6, the organic deposit removing step may include an ozone water supply step of supplying ozone water to the silicon substrate. According to this method, by supplying ozone water to a silicon substrate, organic deposits adhering to one surface of the silicon substrate can be peeled off by the oxidizing power of ozone water.
Furthermore, as described in claim 7, the organic deposit removal step may include a plasma irradiation step (S20) of irradiating plasma on the silicon substrate. According to this method, by irradiating the silicon substrate with plasma, the internal bonds of the organic deposits adhering to one surface of the silicon substrate can be cut, and the organic deposits can be destroyed at the molecular level.

  The invention according to claim 8 is an organic deposit removing means (32; 92; 111, 112; 121, 122, 123) for removing the organic deposit from the silicon substrate (W) ground by using the grinding wheel (85). 131) and hydrofluoric acid-nitric acid mixture supply means (41; 132) for supplying a hydrofluoric acid-nitric acid mixture to one surface of the silicon substrate from which the organic deposits have been removed by the organic deposit removal means A substrate processing apparatus.

According to this structure, the effect similar to the effect described regarding the invention of Claim 1 can be show | played.
The invention according to claim 9 further includes a container holder (5) for holding a substrate container (C) capable of accommodating a silicon substrate, and the organic deposit removing means is accommodated in the substrate container. The substrate processing apparatus according to claim 8, further comprising ultraviolet irradiation means (111, 112) for irradiating the formed silicon substrate with ultraviolet rays.

  According to this configuration, the silicon substrate accommodated in the substrate container is irradiated with ultraviolet rays. Thereby, organic deposits can be removed from the silicon substrate. Since organic deposits can be removed while the silicon substrate is housed in the substrate container, it is not necessary to provide a separate processing chamber. Moreover, since the organic substance removing process can be performed using the period in which the silicon substrate before processing is kept in the substrate container, efficient substrate processing can be performed.

The invention according to claim 10 further includes a container holder (5) for holding a substrate container (C) capable of accommodating a silicon substrate, wherein the organic deposit removing means is accommodated in the substrate container. 10. The substrate processing apparatus according to claim 8, further comprising ozone gas supply means (121, 122, 123) for supplying ozone gas to the silicon substrate.
According to this configuration, ozone gas is supplied to the silicon substrate accommodated in the substrate container. With this ozone gas, organic deposits can be removed from the silicon substrate.

  The invention according to claim 11 further includes a substrate transport mechanism (130) for transporting the silicon substrate in a predetermined transport direction (R1), wherein the organic deposit removing means (131) is a substrate transport path by the substrate transport mechanism. In the first position (P3), the organic adhering substance is removed from the silicon substrate, and the hydrofluoric acid / nitric acid mixed solution supplying means is provided in the substrate transfer path with respect to the substrate transfer direction. 9. The substrate processing apparatus according to claim 8, wherein the substrate processing apparatus is provided so as to supply the hydrofluoric acid-nitric acid mixture toward the second position (P4) downstream of the position.

  According to this configuration, it is possible to remove organic deposits attached to the silicon substrate during the transfer of the silicon substrate by the substrate transfer mechanism.

1 is an illustrative plan view showing a layout of a substrate processing apparatus according to a first embodiment of the present invention. It is sectional drawing which shows the structure of the UV processing chamber shown in FIG. 1 schematically. FIG. 2 is a cross-sectional view schematically showing the configuration of the nitrous acid treatment chamber shown in FIG. 1. FIG. 2 is a plan sectional view schematically showing the internal configuration of the nitrous acid treatment chamber shown in FIG. 1. It is a block diagram which shows the electric constitution of the substrate processing apparatus shown in FIG. It is process drawing for demonstrating the thinning process given to a wafer. It is a figure for demonstrating a bonding process, a grinding process, UV irradiation process, and a nitric acid supply process. It is a perspective view which shows a grinding device. It is sectional drawing which shows the structure of the substrate processing apparatus which concerns on 2nd Embodiment of this invention. It is sectional drawing which shows the structure of a part of substrate processing apparatus which concerns on 3rd Embodiment of this invention. It is sectional drawing which shows the structure of a part of substrate processing apparatus which concerns on 4th Embodiment of this invention. It is process drawing for demonstrating the substrate processing method which concerns on 5th Embodiment of this invention. It is an illustrative perspective view for demonstrating the structure of the substrate processing apparatus which concerns on 6th Embodiment of this invention. It is an illustrative top view for demonstrating the mode of the process by the substrate processing apparatus of FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a schematic plan view showing a layout of a substrate processing apparatus according to an embodiment of the present invention. In this substrate processing apparatus, thinning (thinning) of a wafer W is performed on a back surface of a circular silicon wafer (silicon substrate) W (hereinafter simply referred to as “wafer W”) opposite to the surface on the device forming region side. This is a single-wafer type apparatus for performing an etching process. In this etching process, for example, a hydrofluoric acid nitric acid mixed liquid (hereinafter referred to as “fluoronitric acid”) is used as an etching liquid.

  This substrate processing apparatus includes a UV processing chamber 2 for irradiating the back surface of the wafer W with ultraviolet light, a nitrous acid processing chamber 3 for supplying nitrous acid to the back surface of the wafer W, and a transfer for transferring the wafer W. Chamber 4. The transfer chamber 4 is disposed between the UV processing chamber 2 and the fluorinated nitric acid processing chamber 3. The UV processing chamber 2, the transfer chamber 4, and the nitrous acid processing chamber 3 are arranged in a line in this order along a predetermined horizontal direction (X direction). A container placement table (container holder) 5 for placing the substrate container C is provided on the side of the transfer chamber 4 (upper side shown in FIG. 1).

A plurality (two in FIG. 1) of substrate containers C are arranged side by side along the X direction on the container mounting table 5. In the substrate container C, a plurality of wafers W are stored in a stacked state. The container mounting table 5 is arranged on one side in the Y direction (horizontal direction orthogonal to the X direction) when viewed from the transfer chamber 4.
A partition 6 that divides the UV processing chamber 2 and the transfer chamber 4 is formed with a first opening 11 for carrying the wafer W into and out of the UV processing chamber 2. A first door 14 for opening and closing the first opening 11 is provided on the inner surface of the partition wall 6 (the surface facing the transfer chamber 4).

A second opening 12 for carrying the wafer W in and out of the nitric acid treatment chamber 3 is formed in the partition wall 7 that partitions the nitric acid treatment chamber 3 and the transfer chamber 4. A second door 15 for opening and closing the second opening 12 is provided on the inner surface of the partition wall 7 (the surface facing the transfer chamber 4).
A plurality of third openings 13 (two in FIG. 1) are formed in the partition wall 8 that partitions the transfer chamber 4 and the container mounting table 5 into and out of the substrate container C. A third door 16 for opening and closing the third opening 13 is provided on the inner surface of the partition wall 8 (the surface facing the transfer chamber 4).

  A transfer robot 17 for transferring the wafer W is arranged in the transfer chamber 4. The transfer robot 17 includes a Y-direction rail 18 that extends in the Y direction in the transfer chamber 4, a support shaft 19 that extends in the vertical direction and is slidable on the Y-direction rail 18 along the Y direction, The support shaft 19 includes a hand arm 20 that is supported rotatably around the support shaft 19 and extends in the horizontal direction, and a hand 21 that is coupled to the tip of the hand arm 20 and holds the wafer W. Yes. The Y-direction rail 18 is held on the X-direction rail 22 extending along the X direction so as to be slidable in the direction along the X direction. The X-direction rail 22 is in contact with both ends of the Y-direction rail 18 and is fixed to the lower wall of the transfer chamber 4 (a partition wall corresponding to the lower surface of the transfer chamber 4).

  An X-direction drive mechanism 23 is coupled to the Y-direction rail 18. With the driving force of the X direction drive mechanism 23, the Y direction rail 18 can be slid along the X direction together with the support shaft 19. A Y-direction drive mechanism 24 is coupled to the support shaft 19. The support shaft 19 can be slid along the Y direction by the driving force of the Y-direction drive mechanism 24. A hand arm swing drive mechanism 25 is coupled to the hand arm 20. The hand arm 20 can be rotated around the support shaft 19 by the driving force of the hand arm swing driving mechanism 25.

  By rotating the hand arm 20 around the support shaft 19, the hand 21 can be made to face each opening (the first opening 11, the second opening 12, and the third opening 13). When the Y-direction drive mechanism 24 is driven in a state where the hand 21 faces the third opening 13, the hand 21 passes through the third opening 13 into the substrate container C disposed on the container mounting table 5. Can enter. Accordingly, the transfer robot 17 can take out the wafer W from the substrate container C and store the wafer W in the substrate container C.

Further, the X direction driving mechanism 23 is driven in a state where the hand 21 faces the first opening 11, whereby the hand 21 can enter the UV processing chamber 2 through the first opening 11. Thereby, the transfer robot 17 can carry the wafer W into the UV processing chamber 2 and can carry the wafer W out of the UV processing chamber 2.
Furthermore, by driving the X-direction drive mechanism 23 with the hand 21 facing the second opening 12, the hand 21 can enter the inside of the nitric acid treatment chamber 3 through the second opening 12. As a result, the transfer robot 17 can carry the wafer W into the nitric acid treatment chamber 3 and can carry the wafer W out of the fluoric acid treatment chamber 3.

FIG. 2 is a cross-sectional view schematically showing the configuration of the UV processing chamber 2. The UV processing chamber 2 is partitioned by a partition, and a wafer mounting table 30 for mounting the wafer W therein and an ultraviolet ray on the back surface (upper surface) of the wafer W mounted on the wafer mounting table 30. And an ultraviolet irradiating device 31 for irradiating.
The ultraviolet irradiation device 31 is disposed above the wafer mounting table 30 and includes a plurality of (three in this embodiment) ultraviolet lamps (organic deposit removing means) 32. The ultraviolet lamp 32 extends in the horizontal direction, and the distance between the ultraviolet lamp 32 and the upper surface of the wafer mounting table 30 is, for example, about 50 mm. As each ultraviolet lamp 12, a low-pressure mercury lamp (for example, manufactured by Sen Special Light Source Co., Ltd.) that generates ultraviolet rays having peak wavelengths of 184.9 nm and 253.7 nm is employed. Accordingly, the illuminance of the ultraviolet light of 184.9 nm on the upper surface of the wafer mounting table 30 is, for example, 4 nW / cm ² , and the illuminance of the ultraviolet light of 253.7 nm is, for example, 14 nW / cm ² .

A reflector for reflecting the ultraviolet rays generated from each ultraviolet lamp 32 toward the wafer mounting table 30 may be provided in the ultraviolet irradiation device 31.
FIG. 3 is a cross-sectional view schematically showing the configuration of the nitric acid treatment chamber 3. FIG. 4 is a cross-sectional plan view schematically showing the internal configuration of the nitric acid treatment chamber 3.
The nitric acid treatment chamber 3 is partitioned by a partition, and inside thereof, a substrate holding mechanism 40 for holding the wafer W in a substantially horizontal posture, and an upper surface of the wafer W held by the substrate holding mechanism 40 are fluorinated nitric acid. In order to supply DIW (deionized water) toward the upper surface of the wafer W held by the substrate holding mechanism 40 and a slit nozzle (hydrofluoric acid nitric acid mixture supply means) 41 for supplying The DIW nozzle 42 is provided.

  The substrate holding mechanism 40 includes a rotating shaft 43 that rotates about a vertical axis, a disk-shaped spin base 44 that is fixed to the upper end of the rotating shaft 43, and a substrate support member 45 that is fixed on the spin base 44. ing. A through hole 46 that penetrates the upper and lower surfaces of the spin base 44 is formed at the center of the spin base 44. A rotational driving force from a rotational driving mechanism 59 including a motor is input to the rotational shaft 43.

  The substrate support member 45 includes a substantially disc-shaped bottom wall portion 47 that extends in the horizontal direction, a cylindrical outer peripheral ring portion 48 that rises upward from the peripheral edge of the bottom wall portion 47, and a radial direction relative to the outer peripheral ring portion 48. A cylindrical fixing portion 49 provided outside and fixed to the spin base 44 and a connection portion 50 connecting the bottom wall portion 47 and the fixing portion 49 are integrally formed. The fixing portion 49 is fixed to the spin base 44 by a plurality of bolts 51. The wafer W is accommodated and held in a cylindrical accommodation recess 52 defined by the upper surface of the bottom wall portion 47 and the inner peripheral surface of the outer peripheral ring portion 48. The outer peripheral ring portion 48 surrounds the outer peripheral end of the wafer W accommodated in the accommodating recess 52. The upper surface of the outer peripheral ring portion 48 is set to be slightly higher than the upper surface of the wafer W accommodated in the accommodating recess 52.

On the upper surface of the bottom wall portion 47, a ring-shaped sealing member 53 is disposed along the periphery of the bottom wall portion 47. The seal member 53 supports the lower surface of the wafer W. The seal member 53 may be a lip packing or a face packing.
A suction nozzle 54 for suction is disposed in the center of the bottom wall portion 47. The front end (upper end) of the suction nozzle 54 has a suction port that opens on the upper surface of the bottom wall 47. A suction pipe 55 extends from the suction nozzle 54 downward in the vertical direction. The suction tube 55 is inserted through the through hole 46 of the spin base 44 and the rotary shaft 43, and the other end is connected to a suction device 56 such as a vacuum generator.

  The substrate holding mechanism 40 is provided with a plurality of (for example, four) lift pins 57 (only two lift pins 57 are shown in FIG. 3). Each lift pin 57 is inserted into a through-hole 46 formed so as to penetrate the spin base 44 in the vertical direction, and is provided so as to be movable up and down with respect to the spin base 44. These lift pins 57 are coupled to a lift pin raising / lowering drive mechanism (not shown) for raising and lowering the lift pins 57 collectively. By driving the lift pin raising / lowering drive mechanism, the wafer W can be raised and lowered between the state accommodated in the accommodating recess 52 and the state detached from the accommodating recess 52 upward.

  The slit nozzle 41 includes a main body 60 having a rectangular parallelepiped outer shape along a predetermined horizontal direction. A slit discharge port 61 that opens linearly along the horizontal direction is formed on the lower surface of the main body 60. The length of the slit discharge port 61 (size in the longitudinal direction) is larger than the diameter of the wafer W. The slit outlet 61 discharges nitric acid in a strip shape along the longitudinal direction of the main body 60.

  A rectangular flexible first sheet 62 is attached in a vertical posture on one side surface (the left side shown in FIG. 3) of the main body 60. Further, a rectangular flexible second sheet 63 is attached to the opposite side surface (right side shown in FIG. 3) of the main body 60 in a vertical posture. The sheet width of the first and second sheets 62 and 63 (the length in the normal direction of the wafer W) is such that the leading edge abuts against the upper surface of the wafer W supported by the substrate support member 45. The width is set such that the two sheets 62 and 63 are bent.

  The slit nozzle 41 is attached to a nozzle arm 64 that extends substantially horizontally. The nozzle arm 64 is supported by a nozzle arm support shaft 71 extending substantially vertically on the side of the substrate holding mechanism 40. A nozzle arm swing drive mechanism 65 is coupled to the nozzle arm support shaft 71, and the nozzle arm support shaft 71 is rotated by the driving force of the nozzle arm swing drive mechanism 65 to swing the nozzle arm 64. It can be moved.

The slit nozzle 41 is connected with a nitrous acid supply pipe 66 communicating with the slit discharge port 61. The nitric acid supply pipe 66 is supplied with nitric acid from a nitric acid supply source, and in the middle of the nitric acid supply pipe 66, nitric acid for switching between supply and stop of supply of the nitric acid to the slit nozzle 41. A valve 67 is interposed.
The DIW nozzle 42 is, for example, a straight nozzle that discharges DIW in a continuous flow state. The DIW nozzle 42 is disposed above the substrate holding mechanism 40 with the discharge port directed toward the center of the wafer W. A DIW supply pipe 68 is connected to the DIW nozzle 42, and DIW from the DIW supply source is supplied through the DIW supply pipe 68. A DIW valve 69 for switching between supply and stop of supply of DIW to the DIW nozzle 42 is interposed in the middle portion of the DIW supply pipe 68.

  By driving the nozzle arm swing drive mechanism 65, the nozzle arm 64 is swung, and the slit nozzle 41 is located at a first scan position P1 (shown by a solid line in FIG. 4) outside the upper region of the substrate holding mechanism 40. , Between the first scan position P1 and a second scan position P2 (shown by a two-dot chain line in FIG. 4) that is 90 ° apart from the rotation center of the wafer W and that is outside the upper region of the substrate support member 45. Are reciprocated along the horizontal direction.

  For example, when the slit nozzle 41 moves from the first scan position P 1 toward the second scan position P 2, the first sheet 62 is on the front side in the traveling direction with respect to the nitrous acid landing position on the upper surface of the wafer W. Move while touching the area. Thereby, the deactivated hydrofluoric acid can be scraped off from the upper surface of the wafer W and removed. Further, the second sheet 63 moves while being in contact with a region on the rear side in the advancing direction from the position where the nitrous acid is deposited on the upper surface of the wafer W. Thereby, the nitric acid supplied to the upper surface of the wafer W can be leveled.

  Further, when the slit nozzle 41 returns from the second scan position P2 toward the first scan position P1, the second sheet 63 is located on the front side in the traveling direction with respect to the nitrous acid landing position on the upper surface of the wafer W. Move while touching the area. Thereby, the deactivated hydrofluoric acid can be scraped off from the upper surface of the wafer W and removed. In addition, the first sheet 62 moves while being in contact with a region on the rear side in the traveling direction with respect to the nitrous acid deposition position on the upper surface of the wafer W. Thereby, the nitric acid supplied to the upper surface of the wafer W can be leveled.

  FIG. 5 is a block diagram showing an electrical configuration of the substrate processing apparatus shown in FIG. The substrate processing apparatus includes a control device 70 configured by, for example, a microcomputer. The control device 70 includes an ultraviolet lamp 32, a rotation drive mechanism 59, a nozzle arm swing drive mechanism 65, a nitric acid valve 67, a suction device 56, a DIW valve 69, an X direction drive mechanism 23, a Y direction drive mechanism 24, and a hand arm. The swing drive mechanism 25 is connected as a control target.

FIG. 6 is a process diagram for explaining the thinning process performed on the wafer W. FIG. FIG. 7 is a diagram for explaining the steps included in the thinning process.
In this thinning process, a grinding process for grinding the back surface of the wafer W is performed, and a nitric acid supply process for supplying nitric acid to the back surface of the wafer W after the grinding process is performed. The thickness of the wafer W is reduced from about 725 μm to about 40 μm by the grinding process and the nitric acid supply process.

  Prior to the grinding step, a glass substrate S as a reinforcing substrate for reinforcing the wafer W is bonded to the surface (device forming surface) of the wafer W via the adhesive A (S1: bonding step. FIG. 7 (a)). The glass substrate S has a disk shape with the same diameter as the wafer W, and has a thickness of, for example, 500 to 700 μm. The bonding of the wafer W and the glass substrate S is performed manually by the operator. The adhesive A is mainly composed of an acrylic resin such as phenoxypolyethylene glycol acrylate or dicyclobentanyl diacrylate.

  Thereafter, the wafer W and the glass substrate S are irradiated with ultraviolet rays by a predetermined ultraviolet irradiation device (not shown) (step S2). Thereby, the adhesive A interposed between the wafer W and the glass substrate S is cured, and the wafer W and the glass substrate S are firmly bonded. Thereby, the wafer W is reinforced by the glass substrate S, the strength of the wafer W is increased, and the wafer W is not easily deformed.

Next, a grinding process (step S3; see FIG. 7B) is performed. In this grinding process, a grinding device 80 is used.
FIG. 8 is a perspective view showing the grinding device 80. The grinding apparatus 80 includes a rotation mechanism (not shown) that holds the wafer W and rotates it around a predetermined vertical axis, a grinding mechanism 81 that grinds the back surface of the wafer W held by the rotation mechanism, and a grinding mechanism 81. A feeding mechanism (not shown) for feeding the rotating mechanism.

  The grinding mechanism 81 includes a cylindrical grind wheel 82 disposed above the rotation mechanism, a disk 83 that supports the grind wheel 82 from above, and a rotation support shaft 84 that extends upward from the center of the disk 83. . A plurality of chip-shaped grinding wheels 85 are arranged in an annular shape at the lower end edge of the grinding wheel 82. Each grinding wheel 85 has a lower surface made of a blade surface. A rotation drive mechanism (not shown) such as a motor is coupled to the rotation support shaft 84.

The grinding wheel 85 is formed by solidifying high-hardness abrasive grains 86 with a binder B. As this binder B, for example, a resinoid binder is employed. This resinoid binder is mainly composed of a thermosetting resin such as a phenol resin. Examples of the material of the abrasive grains 86 include diamond and CBN (cubic boron nitride sintered body).
The wafer W is set on the rotation mechanism with its back surface facing upward. In this state, the back surface of the wafer W faces the lower surface of the grinding wheel 85. The wafer W is rotated around a predetermined axis of rotation passing through the center of the wafer W by the rotation drive of the rotation mechanism. Further, the rotation support shaft 84 is rotated by the rotation drive of the rotation drive mechanism, and the grind wheel 82 is rotated at a high speed around a predetermined rotation axis passing through the center thereof. The rotation axis of the wafer W and the rotation axis of the grinding wheel 82 are deviated. Then, when the grinding mechanism 81 is sent to the rotating mechanism, the lower surface (blade surface) of the grinding wheel 85 that rotates at high speed comes into contact with the rear surface of the wafer W, and the rear surface of the wafer W is ground. Since the rotation axis of the wafer W and the rotation axis of the grinding wheel 82 are deviated, the entire back surface of the wafer W is ground. Although a relatively large force acts on the wafer W in the grinding process, since the wafer W is reinforced by the glass substrate S, deformation of the wafer W can be prevented.

As the grinding of the wafer W progresses, the binder B contained in the grinding wheel 85 is crushed and dispersed around. For this reason, the crushed binder B may adhere to the back surface of the wafer W.
Further, the resin adhesive A interposed between the wafer W and the glass substrate S may protrude from between the wafer W and the glass substrate S. The adhesive A may be crushed by the grinding wheel 85 and dispersed in the periphery, and may adhere to the back surface of the wafer W.

  When the feed amount of the grinding wheel 82 by a feed mechanism (not shown) reaches a predetermined amount, the rotation of the grinding wheel 82 is stopped. Thereafter, the grinding wheel 82 is separated from the back surface of the wafer W. Grinding marks are formed on the back surface of the wafer W after execution of the grinding process. Moreover, there exists a possibility that the fragment | piece of binder B and the adhesive agent A may adhere to the back surface of the wafer W after execution of a grinding process as an organic deposit | attachment.

Next, a water washing process is performed on the wafer W after execution of the grinding process (step S4). As a result, silicon residue generated by the grinding process is removed from the wafer W. However, organic deposits adhering to the back surface of the wafer W are not removed by this water washing process.
The wafer W after the water washing process is accommodated in the substrate container C. The substrate container C is transported to the container mounting table 5 by a container transporting mechanism (not shown) and is held by the container mounting table 5.

When the substrate container C is held on the container mounting table 5, one wafer W is taken out from the substrate container C by the transfer robot 17. The wafer W taken out from the substrate container C is first carried into the UV processing chamber 2 (Step S5), and placed on the wafer placement table 30 with the back surface thereof facing upward.
When the wafer W is mounted on the wafer mounting table 10, the control device 70 turns on the ultraviolet lamp 32. Thereby, the ultraviolet rays generated by the respective ultraviolet lamps 32 are irradiated to the back surface of the wafer W on the wafer mounting table 30 (S6: UV irradiation step, see FIG. 7C). Even if an organic deposit adheres to the back surface of the wafer W, the internal bond of the organic deposit is cut by the irradiation of the ultraviolet rays, and the organic deposit is destroyed at the molecular level.

  When the irradiation of ultraviolet rays in the UV processing chamber 2 is performed for a predetermined time (for example, 15 minutes), the wafer W is unloaded from the UV processing chamber 2 by the transfer robot 17 (step S7), and then into the nitrous acid processing chamber 3. It is carried in (step S8) and placed on the lift pin 57 with its back surface facing upward. Prior to the loading of the wafer W, the slit nozzle 41 is retracted to the retracted position on the side of the substrate holding mechanism 40. Thereafter, a lift pin raising / lowering drive mechanism (not shown) is driven, the lift pins 57 are lowered, and the wafer W is accommodated in the accommodating recess 52. As a result, the wafer W is delivered to the substrate support member 45. After the wafer W is transferred to the substrate support member 45, the control device 70 operates the suction device 56, whereby the wafer W is attracted and held on the substrate support member 45.

After the wafer W is attracted and held on the substrate support member 45, the control device 70 drives the rotation drive mechanism 59 to rotate the spin base 44 and the substrate support member 45 at a constant rotation speed at a low rotation speed (for example, 5 rpm). In addition, the control device 70 drives the nozzle arm swing drive mechanism 65 to guide the slit nozzle 41 upward of the wafer W.
When the slit nozzle 41 reaches above the wafer W, the controller 70 opens the nitric acid valve 67 and discharges the nitric acid from the slit discharge port 61 in a belt-like profile (S9: nitrous acid supply step, FIG. 7 ( d)). The hydrofluoric acid discharged from the slit discharge port 61 is, for example, produced by mixing nitric acid and hydrofluoric acid at a volume ratio of 3.2: 1, and the discharge flow rate is, for example, 2 L / min. . Further, the control device 70 drives the nozzle arm swing drive mechanism 65 to move the slit nozzle 41 to a first scan position P1 (shown by a solid line in FIG. 4) outside the upper region of the substrate support member 45; A reciprocating swing (reciprocating scan) is performed between the second scan position P2 (shown by a two-dot chain line in FIG. 4) outside the region above the substrate support member 45.

The organic deposits on the back surface of the wafer W destroyed at the molecular level in the UV irradiation step (step S6 in FIG. 6) are washed away with fluoric acid and peeled off from the back surface of the wafer W. Then, the wafer material in the surface layer on the back surface of the wafer W is removed by etching with nitrous acid, and the wafer W is thinned.
After a predetermined processing time (for example, 15 minutes) has elapsed, the control device 70 closes the nitric acid valve 67 and stops the discharge of the nitric acid from the slit nozzle 41. In addition, the control device 70 drives the nozzle arm swing drive mechanism 65 to retract the slit nozzle 41 to the retract position on the side of the substrate holding mechanism 40. Grinding marks do not exist on the back surface of the wafer W after the hydrofluoric acid / nitric acid mixture supplying step.

  Next, the control device 70 controls the rotational drive mechanism 59 to accelerate the rotational speed of the spin base 44 and the substrate support member 45 to a predetermined rinse processing rotational speed (about 100 rpm), and opens the DIW valve 69. The DIW is supplied from the DIW nozzle 42 toward the rotation center of the upper surface of the wafer W in the rotating state. Thereby, the nitric acid on the back surface of the wafer W is washed away, and the wafer W is rinsed (step S10). The discharge flow rate of DIW from the DIW nozzle 42 in this rinsing process is, for example, 2.0 L / min.

  After performing this rinsing process for a predetermined time (for example, 60 seconds), the control device 70 closes the DIW valve 69 and ends the rinsing process. The control device 70 further controls the chuck rotation drive mechanism 59 to accelerate the rotation speed of the spin base 44 and the substrate support member 45 to a predetermined drying rotation speed (about 2500 rpm). As a result, the DIW on the upper surface of the wafer W is shaken off by the centrifugal force, and the wafer W is spin-dried (step S11).

  After performing the spin dry process for a predetermined time (for example, 30 seconds), the control device 70 controls the rotation drive mechanism 59 to stop the rotation of the spin base 44 and the substrate support member 45. Thereafter, the control device 70 stops the driving of the suction device 56, the decompressed state of the space between the wafer W and the upper surface of the bottom wall portion 47 of the substrate support member 45 is released, and the suction holding of the wafer W is released. Is done. Next, the lift pin raising / lowering drive mechanism is driven to lift the lift pins 57, and the processed wafer W is detached from the accommodating recess 52 upward.

Thereafter, the processed wafer W is unloaded from the nitric acid treatment chamber 3 by the transfer robot 17 (step S12), and then accommodated in the substrate container C held on the container mounting table 5.
After completion of the thinning process, the wafer W after the thinning process and the glass substrate S are separated using an ultraviolet irradiation device (not shown) (step S13). The wafer W and the glass substrate S are irradiated with ultraviolet rays having a relatively large irradiation amount, and then immersed in warm water at a predetermined temperature (for example, 90 ° C.) for a predetermined time (for example, 1 minute). At this time, due to the difference in thermal expansion coefficient between the wafer W and the glass substrate S, a force that separates both acts between the wafer W and the glass substrate S, and the wafer W and the glass substrate S are separated. The

  As described above, according to this embodiment, the UV irradiation process (step S6 in FIG. 6) is performed prior to the nitric acid supply process in step S9. In the UV irradiation process, organic deposits generated in the grinding process in step S3 are destroyed at the molecular level. And since a nitric acid supply process is performed after destruction of an organic deposit | attachment, the etching of the back surface of the wafer W by a fluorinated nitric acid is not inhibited by an organic deposit | attachment. Thus, the wafer W can be thinned while preventing or suppressing the occurrence of surface roughness on the back surface of the wafer W.

FIG. 9 is a cross-sectional view showing a configuration of a substrate processing apparatus according to another embodiment (second embodiment) of the present invention. In the substrate processing apparatus according to the second embodiment, an SPM processing chamber 90 is provided instead of the UV processing chamber 2 of the substrate processing apparatus of the first embodiment shown in FIGS.
The SPM processing chamber 90 is provided so as to be surrounded by a partition wall, and includes a spin chuck 91 for holding and rotating the wafer W substantially horizontally, and a back surface of the wafer W held by the spin chuck 91. DIW is applied to the center of the back surface of the wafer W held by the nozzle (organic deposit removing means) 92 for discharging SPM (mixed sulfuric acid and hydrogen peroxide solution) 92 toward the (upper surface) and the spin chuck 91. A DIW nozzle 102 for supply is accommodated.

  The spin chucks 91 are provided at substantially equal intervals at a plurality of locations around the motor 93, a disc-shaped spin base 94 that is rotated around the vertical axis by the rotational driving force of the motor 93, and the periphery of the spin base 94, and A plurality of clamping members 95 are provided for clamping W in a substantially horizontal posture. Thus, the spin chuck 91 keeps the wafer W in a substantially horizontal posture by rotating the spin base 94 by the rotational driving force of the motor 93 in a state where the wafer W is held by the plurality of holding members 95. In this state, it can be rotated around the vertical axis together with the spin base 94.

  The nozzle 92 is attached to the tip of a nozzle arm 96 extending substantially horizontally above the spin chuck 91, and has a so-called straight nozzle configuration. The base end portion of the nozzle arm 96 is supported by the upper end portion of an arm support shaft 97 extending substantially vertically on the side of the spin chuck 91. A nozzle driving mechanism 98 including a motor (not shown) is coupled to the arm support shaft 97. By inputting a rotational force from the nozzle drive mechanism 98 to the arm support shaft 97 and rotating the arm support shaft 97, the nozzle arm 96 can be swung above the spin chuck 91.

An SPM supply pipe 99 to which SPM from an SPM supply source is supplied is connected to the nozzle 92. An SPM valve 100 for opening and closing the SPM supply pipe 99 is interposed in the middle of the SPM supply pipe 99.
DIW is supplied to the DIW nozzle 102 via the DIW valve 101.

  In the second embodiment, the wafer W after the water washing process (step S4 shown in FIG. 6) taken out from the substrate container C by the transfer robot 17 is carried into the SPM processing chamber 90, and the back surface thereof is directed upward. It is held by the spin chuck 91. When the wafer W is held by the spin chuck 91, the motor 93 is driven to rotate the spin chuck 91 at a predetermined liquid processing speed.

After the rotation of the wafer W is started, the nozzle drive mechanism 98 is controlled to move the nozzle 92 from the standby position on the side of the spin chuck 91 to above the wafer W held on the spin chuck 91. Then, the SPM valve 100 is opened, and SPM is discharged from the nozzle 92 toward the back surface of the rotating wafer W.
In this SPM process, the nozzle drive mechanism 98 is controlled, and the nozzle arm 96 is swung within a predetermined angle range. As a result, the supply position on the back surface of the wafer W to which the SPM from the nozzle 92 is guided is within a range from the rotation center of the wafer W to the peripheral edge of the wafer W, and an arcuate locus that intersects the rotation direction of the wafer W. Move back and forth while drawing. Further, the SPM supplied to the back surface of the wafer W spreads over the entire back surface of the wafer W. Therefore, the SPM is supplied uniformly over the entire back surface of the wafer W. Even if organic deposits adhere to the back surface of the wafer W, the strong oxidizing power of peroxomonosulfuric acid contained in the SPM acts on the organic deposits, and the organic deposits are peeled off and removed from the back surface of the wafer W.

When the reciprocating movement of the SPM supply position is performed a predetermined number of times, the SPM valve 100 is closed, the supply of SPM to the wafer W is stopped, and the nozzle 92 is returned to the side retracted position of the spin chuck 91.
Next, the DIW valve 101 is opened while the rotation of the wafer W is continued, and DIW is discharged from the DIW nozzle 9 toward the center of the back surface of the rotating wafer W. The DIW supplied onto the back surface of the wafer W spreads over the entire back surface of the wafer W, and the SPM adhering to the back surface of the wafer W is washed away by the DIW.

  Further, the motor 93 is driven to increase the rotation speed of the wafer W to a predetermined drying rotation speed (about 2500 rpm), and the DIW droplets adhering to the wafer W are removed. Thereafter, the wafer W is unloaded from the SPM processing chamber 90 by the transfer robot 17 and is loaded into the nitronitric acid processing chamber 3 as in step S8 of FIG. Thereafter, a nitric acid supply step (step S9 in FIG. 6) is performed.

  FIG. 10 is a sectional view showing a partial configuration of a substrate processing apparatus according to another embodiment (third embodiment) of the present invention. 10, parts corresponding to those shown in the above-described embodiment (first embodiment) of FIGS. 1 to 8 are denoted by the same reference numerals as in FIGS. The description is omitted. The substrate processing apparatus according to the third embodiment is different from the substrate processing apparatus according to the first embodiment in that ultraviolet lamps (ultraviolet irradiation means) 111 and 112 are accommodated in the transfer chamber 4.

  The 3rd opening 13 of the partition 8 which partitions off the conveyance chamber 4 and the container mounting base 5 is formed in the substantially square shape by front view. The upper side and the lower side of the third opening 13 are formed along the horizontal direction, and the both sides of the third opening 13 are formed along the vertical direction. In the transfer chamber 4, a pair of upper and lower ultraviolet lamps 111 and 112 are arranged at positions close to the partition wall 8. The ultraviolet upper lamp 111 is disposed along the upper side of the third opening 13. The ultraviolet upper lamp 111 is disposed along the lower side of the third opening 13. As these ultraviolet lamps 111 and 112, those similar to the ultraviolet lamp 32 of the first embodiment described above are employed.

  The substrate container C mounted on the container mounting table 5 is capable of storing a plurality of substrates W in a stacked state at a predetermined interval. The substrate container C is a FOUP (Front Opening Unified Pod) that accommodates the substrate W in a sealed state. That is, the substrate container C includes a substantially cubic main body 114 having a substrate inlet / outlet 113 for loading / unloading the substrate W on one side surface, and a lid (not shown in FIG. 10). Open state). In a state where the substrate container C is placed on the container placement table 5, the substrate entrance 113 faces the third opening 13.

The third door 16 (see FIG. 1; not shown in FIG. 10) is movable between a closed state that covers the third opening 13 and an open state that retreats to the lower portion of the third opening 13 in the partition wall 8. Is provided. In the open state of the third door 16, almost the entire area of the third opening 8 is opened.
The wafer W after the water washing process (step S4 in FIG. 6) is accommodated in the substrate container C. The substrate container C is transported to the container mounting table 5 by a container transporting mechanism (not shown) and is held on the container mounting table 5. Thereafter, the third door 16 and the lid are opened (see FIG. 10), and the ultraviolet lamps 111 and 112 are turned on. The ultraviolet rays irradiated from the ultraviolet lamps 111 and 112 are applied to the wafer W accommodated in the substrate container C through the substrate entrance / exit 113 of the substrate container C. Even if an organic deposit adheres to the back surface of the wafer W, the internal bond of the organic deposit is cut by the irradiation of the ultraviolet rays, and the organic deposit is destroyed at the molecular level. Thereby, in the state which accommodated the wafer W in the substrate container C, the organic deposit | attachment adhering to the said wafer W can be destroyed at a molecular level.

After a predetermined time has elapsed, the wafer W is taken out of the substrate container C by the transfer robot 17 and carried into the UV processing chamber 2 as in step S5 of FIG. And a UV irradiation process (step S6 of FIG. 6) is performed. Thereafter, it is carried into the fluoric acid treatment chamber 3. A nitric acid supply step (step S9 in FIG. 6) is performed.
In the third embodiment, since the wafer W is irradiated with ultraviolet rays while the wafer W is accommodated in the substrate container C, the ultraviolet irradiation step of step S6 in the UV processing chamber 2 can be omitted. In this case, the wafer W in the substrate container C is directly carried into the nitric acid treatment chamber 3 by the transfer robot 17.

In the above description, the case where a pair of upper and lower ultraviolet lamps 111 and 112 are disposed has been described as an example. However, only one of the ultraviolet lamps 111 and 112 may be provided. Furthermore, ultraviolet lamps can be arranged along the left and right sides of the third opening 13.
FIG. 11 is a cross-sectional view showing a partial configuration of a substrate processing apparatus according to another embodiment (fourth embodiment) of the present invention. 11, parts corresponding to those shown in the above-described embodiment (first embodiment) in FIGS. 1 to 8 and the embodiment (third embodiment) in FIG. The same reference numerals as those in the case of FIG. The configuration shown in FIG. 11 is significantly different from the configuration shown in FIG. 10 in that an ozone gas introduction mechanism 120 for introducing ozone gas into the substrate container C is provided in place of the ultraviolet lamps 111 and 112.

  The ozone gas introduction mechanism 120 includes an ozone gas upper nozzle (ozone gas supply means) 121, an ozone gas lower nozzle (ozone gas supply means) 122, and an ozone gas introduction nozzle (ozone gas supply means) 123. The ozone gas upper nozzle 121 and the ozone gas lower nozzle 122 are arranged at positions near the partition wall 8 in the transfer chamber 4 so that the discharge ports thereof face the substrate inlet / outlet 113 of the substrate container C. A plurality of ozone gas upper nozzles 121 are provided along the upper side of the third opening 13 (only one is shown in FIG. 11). A plurality of ozone gas lower nozzles 122 are provided along the lower side of the third opening 13 (only one is shown in FIG. 11). Ozone gas is supplied to the ozone gas upper nozzle 121 and the ozone gas lower nozzle 122 via an ozone gas valve 127.

  The ozone gas introduction nozzle 123 is provided on the container mounting table 5. A discharge port facing upward is formed at the tip of the ozone gas introduction nozzle 123. The ozone gas introduction nozzle 123 is embedded in the container mounting table 5, and only the tip portion projects upward from the upper surface of the container mounting table 5. An ozone gas supply pipe 124 to which ozone gas from an ozone gas supply source is supplied is connected to the ozone gas introduction nozzle 123.

An introduction hole 125 is formed in the bottom surface of the substrate container C. In addition, on the bottom surface of the substrate container C, a lead-out hole 126 for discharging the atmosphere in the substrate container C from the substrate container C to the outside of the container C is formed.
In a state where the substrate container C is placed on the container carrier table 5, the ozone gas introduction nozzle 123 is inserted into the introduction hole 125 formed in the bottom surface of the substrate container C. The discharge port of the ozone gas introduction nozzle 123 inserted into the introduction hole 125 faces the internal space of the substrate container C. On the other hand, when the substrate container C is detached from the container mounting table 5, the ozone gas introduction nozzle 123 is pulled out from the introduction hole 125. An introduction opening / closing mechanism (not shown) is disposed in the introduction hole 125. This introduction opening / closing mechanism normally closes the introduction hole 125, opens the introduction hole 125 in conjunction with the insertion operation of the ozone gas introduction nozzle 123, and closes the introduction hole 125 by the extraction operation of the ozone gas introduction nozzle 123. . A lead opening / closing mechanism (not shown) is disposed in the lead hole 126. This outlet opening / closing mechanism normally closes the outlet hole 126, opens the outlet hole 126 in conjunction with the opening operation of the inlet opening / closing mechanism, and blocks the inlet hole 125 in conjunction with the closing operation of the inlet opening / closing mechanism. To do.

The wafer W after the water washing process (step S4 in FIG. 6) is accommodated in the substrate container C. The substrate container C is transported to the container mounting table 5 by a container transport mechanism (not shown).
An engagement pin (not shown) provided on the container mounting table 5 is engaged with a groove (not shown) formed in the bottom of the substrate container C, so that the substrate container is attached to the container mounting table 5. C is fixed. In a state where the substrate container C is placed on the container table 5, the ozone gas introduction nozzle 123 is inserted into the introduction hole 125 of the substrate container C so that the discharge port faces the internal space of the substrate container C. Become. At this time, the introduction hole 125 is opened in conjunction with the insertion operation of the ozone gas introduction nozzle 123 by the introduction opening / closing mechanism (not shown). Thereby, ozone gas is discharged from the discharge port of the ozone gas introduction nozzle 123 and ozone gas is introduced into the substrate container C. The discharge of ozone gas from the ozone gas introduction nozzle 123 is continued while the substrate container C is being placed on the container placing table 5.

  Thereafter, the third door 16 and the lid (not shown; FIG. 11 shows the open state of the lid) are opened, and the third opening 13 and the substrate doorway 113 are opened. When the third opening 13 and the substrate inlet / outlet 113 are opened, the ozone gas valve 127 is opened, and ozone gas is blown from the ozone gas upper nozzle 121 and the ozone gas lower nozzle 122 to the substrate inlet / outlet 113 of the substrate container C. The blowing of ozone gas by the ozone gas upper nozzle 121 and the ozone gas lower nozzle 122 is continued while the third opening 13 is opened.

  Therefore, ozone gas is supplied to the plurality of wafers W accommodated in the substrate container C. Even if organic deposits adhere to the back surface of the wafer W, the organic deposits are oxidized by ozone gas, and the organic deposits are destroyed at the molecular level. Thereby, in the state which accommodated the wafer W in the substrate container C, the organic deposit | attachment adhering to the said wafer W can be destroyed at a molecular level.

After a lapse of a predetermined time, the wafer W is taken out from the substrate container C by the transfer robot 17 and loaded into the UV processing chamber 2 as shown in step S5 in FIG. 6, and the UV irradiation process (step S6 in FIG. 6) is executed. Is done. Thereafter, a nitric acid supply step (step S9 in FIG. 6) is performed in the nitric acid treatment chamber 3.
In the fourth embodiment, since the wafer W is irradiated with ultraviolet rays while the wafer W is accommodated in the substrate container C, the ultraviolet irradiation step of step S6 in the UV processing chamber 2 can be omitted. In this case, the wafer W in the substrate container C is directly carried into the nitric acid treatment chamber 3 by the transfer robot 17.

  In the above description, the case where ozone gas is blown to the substrate inlet / outlet 113 of the substrate container C by the ozone gas upper nozzle 121 and the ozone gas lower nozzle 122 has been described as an example. It may be performed by an ozone gas nozzle disposed in the vicinity of the side of the three openings 13. Further, as the ozone gas introduction mechanism 120, ozone gas is introduced into the substrate container C through nozzles 121 and 122 for blowing ozone gas to the substrate inlet / outlet 113 of the substrate container C and an introduction hole 125 formed in the bottom surface of the substrate container C. In the above description, both the ozone gas introduction nozzle 123 and the ozone gas introduction nozzle 123 are described as examples. However, only one of them may be provided.

  FIG. 12 is a process diagram for explaining a substrate processing method (thinning process) according to still another embodiment (fifth embodiment) of the present invention. In FIG. 12, steps corresponding to the steps shown in FIG. 6 (first embodiment) described above are denoted by the same reference numerals as in FIG. 6, and description thereof is omitted. The thinning process shown in FIG. 12 is different from the thinning process shown in FIG. 6 in that the plasma irradiation process in step S20 is executed instead of the UV irradiation process (step S6 in FIG. 6). . A plasma device (not shown) (not shown) is used for executing this plasma irradiation step.

  After the water washing process in step S4, the wafer W is accommodated in a plasma processing chamber (not shown) of the plasma apparatus. In the state where the processing gas is filled, a microwave as a high frequency power is output from a high frequency power source (not shown), whereby the microwave is radiated to the plasma processing chamber. Then, the high-density plasma of the processing gas is excited in the plasma processing chamber by the energy of the emitted microwave.

Even if an organic deposit adheres to the back surface of the wafer W, the internal bond of the organic deposit is broken by the plasma irradiation, and the organic deposit is destroyed at the molecular level. Thereafter, the wafer W is accommodated in the substrate container C. The substrate container C is transported to the container mounting table 5 by a container transporting mechanism (not shown) and is held by the container mounting table 5.
The wafer W accommodated in the substrate container C held on the container mounting table 5 is taken out from the substrate container C by the transfer robot 17. Then, the wafer W taken out from the substrate container C is carried into the fluoric acid treatment chamber 3 (step S8).

FIG. 13 is an illustrative perspective view for explaining the configuration of a substrate processing apparatus according to another embodiment (sixth embodiment) of the present invention. This substrate processing apparatus is an apparatus for performing an etching process for thinning the wafer W on the back surface of the wafer W.
The substrate processing apparatus includes a roller transport mechanism (substrate transport mechanism) 130 for transporting the wafer W along a predetermined transport direction R1 and a back surface of the wafer W being transported by the roller transport mechanism 130. An ultraviolet lamp (organic deposit removing means) 131 for irradiating ultraviolet rays, and a nitric acid nozzle for supplying nitric acid to the back surface of the wafer W being transported by the roller transport mechanism 130 (supplying a mixed solution of hydrofluoric acid and nitric acid) Means) 132.

  The ultraviolet lamp 131 and the nitric acid nozzle 132 are disposed above the roller transport mechanism 130. The ultraviolet lamp 131 is the same as the ultraviolet lamp 32 of the first embodiment described above. The nitric acid nozzle 132 has a slit-like discharge port extending downward in a direction substantially perpendicular to the transfer direction R1 of the wafer W. From the discharge port of the nitric acid nozzle 132, curtain-like (curtain-like) hydrofluoric acid is discharged downward. Therefore, as shown in the schematic plan view of FIG. 14, the ultraviolet irradiation position (first position) P3 on the roller transport mechanism 130 is orthogonal to the transport direction R1 of the wafer W. The etching solution supply position (second position) P4 on the roller transport mechanism 130 has a form of cleaning that extends across the entire width of the substrate W perpendicular to the transport direction R1 of the wafer W. As clearly shown in FIG. 14, the nitric acid supply position P4 is disposed downstream from the ultraviolet irradiation position P3 by a predetermined distance D in the substrate transport direction R1.

The wafer W after the water washing process (step S4 shown in FIG. 6) taken out from the substrate container C by the transfer robot 17 is placed on the roller transfer mechanism 130 with its back surface facing upward.
By transporting the wafer W at a predetermined speed along the transport direction R1 by the roller transport mechanism 130, the back surface of the wafer W is sequentially scanned by the ultraviolet irradiation position P3 and the nitric acid supply position P4. As a result, the back surface of the wafer W is first irradiated with ultraviolet rays, and thereafter, nitric acid is supplied with a delay of a predetermined time. Thereby, it is possible to execute the irradiation of ultraviolet rays and the supply of nitric acid on the back surface of the wafer W in parallel.

  The rinsing step after the treatment using the nitric acid can be performed by supplying DIW to the back surface of the wafer W from the DIW nozzle 133 provided downstream of the nitric acid nozzle 132 in the transport direction R1 as shown in FIG. The DIW nozzle 133 has a slit-like discharge port extending in a direction substantially perpendicular to the transfer direction R1 of the wafer W on the lower side, and supplies DIW to a range over the entire width of the wafer W transferred by the roller transfer mechanism 130. It is something that can be done.

Although six forms of the present invention have been described above, the present invention can be implemented in other forms.
In the second embodiment described above, ozone water can be supplied instead of SPM. That is, an ozone water supply pipe 140 (shown by a two-dot chain line in FIG. 9) to which ozone water from an ozone water supply source is supplied is connected to the nozzle 92, and in the middle of the ozone water supply pipe 140, An ozone water valve 141 (shown by a two-dot chain line in FIG. 9) for opening and closing the ozone water supply pipe 140 may be interposed.

  When supplying the ozone water, the supply position on the back surface of the wafer W to which the ozone water from the nozzle 92 is guided is within the range from the rotation center of the wafer W to the peripheral edge of the wafer W. Reciprocating while drawing an arc-shaped trajectory intersecting with. Further, the ozone water supplied to the back surface of the wafer W spreads over the entire back surface of the wafer W. Therefore, the ozone water is uniformly supplied to the entire back surface of the wafer W. By supplying ozone water to the back surface of the wafer W, the oxidizing power of ozone water acts on the organic deposits, and the organic deposits can be peeled off from the back surface of the wafer W and removed.

In the third embodiment, the ultraviolet lamp is described as being arranged along the upper side and the lower side of the third opening 13. However, the ultraviolet lamp may be arranged along the left and right sides of the third opening 13. it can.
Moreover, it can also be set as the structure which provides both the ultraviolet lamps 111 and 112 of 3rd Embodiment, and the ozone gas introduction mechanism 120 of 4th Embodiment.

In the third and fourth embodiments, a FOUP (Front Opening Unified Pod) that accommodates the wafer W in a sealed state is illustrated as the substrate container C. However, other than this, a SMIF (Standard Mechanical Interface) ) Other types of substrate containers such as pods and OC (Open Cassette) can also be used.
Further, in the first to fourth embodiments, an ultraviolet lamp can be disposed in the nitrous acid treatment chamber 3. At this time, ultraviolet rays from the ultraviolet lamp are applied to the back surface of the wafer W held by the substrate holding mechanism 40. Then, after irradiating the back surface of the wafer W with ultraviolet rays, a nitrous acid supply step can be performed.

  In addition, various design changes can be made within the scope of matters described in the claims.

5 Container placement table (container holder)
32 UV lamp (Organic deposit removal means)
41 Slit nozzle (hydrofluoric acid nitric acid mixture supply means)
85 Grinding wheel 86 Abrasive grain 92 Nozzle (Organic deposit removal means)
111 Ultraviolet lamp (ultraviolet irradiation means)
112 UV lower lamp (UV irradiation means)
121 Ozone gas upper nozzle (ozone gas supply means)
122 Ozone gas lower nozzle (ozone gas supply means)
123 Ozone gas introduction nozzle (ozone gas supply means)
130 Roller transport mechanism (substrate transport mechanism)
131 UV lamp (Organic deposit removal means)
132 Fluoric acid nozzle (Metric acid supply means)
A Adhesive B Binder C Substrate container P3 UV irradiation position (first position)
P4 nitrous acid supply position (second position)
R1 Transport direction S Glass substrate (reinforcement substrate)
W wafer (silicon substrate)

Claims (11)

A grinding process of grinding a silicon substrate using a grinding wheel;
From the silicon substrate after execution of the grinding step, an organic deposit removal step for removing organic deposits generated in the grinding step,
A substrate processing method comprising: a hydrofluoric acid / nitric acid mixture supplying step for supplying a hydrofluoric acid / nitric acid mixture to one surface of the silicon substrate after the organic deposit removing step.   The bonding step of bonding a reinforcing substrate for reinforcing the silicon substrate to the other surface opposite to the one surface of the silicon substrate via an adhesive prior to the grinding step. Substrate processing method.   The substrate processing method according to claim 1, wherein the organic deposit removal step includes an ultraviolet irradiation step of irradiating the silicon substrate with ultraviolet rays.   The substrate processing method according to claim 1, wherein the organic deposit removal step includes an ozone gas supply step of supplying ozone gas to the silicon substrate.   5. The substrate processing method according to claim 1, wherein the organic deposit removal step includes a sulfuric acid hydrogen peroxide solution supply step of supplying a sulfuric acid hydrogen peroxide solution mixed solution to the silicon substrate.   The substrate treatment method according to any one of claims 1 to 5, wherein the organic deposit removal step includes an ozone water supply step of supplying ozone water to the silicon substrate.   The substrate processing method according to claim 1, wherein the organic deposit removing step includes a plasma irradiation step of irradiating a silicon substrate with plasma. Organic deposit removal means for removing organic deposits from a silicon substrate ground using a grinding wheel;
A substrate processing apparatus, comprising: a hydrofluoric acid / nitric acid mixture supply unit configured to supply a hydrofluoric acid / nitric acid mixture to one surface of the silicon substrate after the organic deposits are removed by the organic adhesion removal unit. Further including a container holder for holding a substrate container capable of accommodating a silicon substrate;
9. The substrate processing apparatus according to claim 8, wherein the organic deposit removing means includes ultraviolet irradiation means for irradiating the silicon substrate accommodated in the substrate container with ultraviolet rays. Further including a container holder for holding a substrate container capable of accommodating a silicon substrate;
The substrate processing apparatus according to claim 8 or 9, wherein the organic deposit removing means includes an ozone gas supply means for supplying ozone gas to the silicon substrate accommodated in the substrate container. A substrate transport mechanism for transporting the silicon substrate in a predetermined transport direction;
The organic deposit removing means is provided to remove the organic deposit from the silicon substrate at a first position of the substrate transport path by the substrate transport mechanism;
The hydrofluoric acid nitric acid mixture supply means is provided to supply the hydrofluoric acid nitric acid mixture toward a second position downstream of the first position in the substrate transport path with respect to the substrate transport direction. The substrate processing apparatus according to claim 8.

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