WO2020066492A1

WO2020066492A1 - Substrate processing system and substrate processing method

Info

Publication number: WO2020066492A1
Application number: PCT/JP2019/034565
Authority: WO
Inventors: 隼斗田之上
Original assignee: 東京エレクトロン株式会社
Priority date: 2018-09-25
Filing date: 2019-09-03
Publication date: 2020-04-02
Also published as: JPWO2020066492A1; JP7086201B2; TW202018794A

Abstract

Provided is a substrate processing system for processing a substrate, the system comprising: a separating section for separating the substrate into a first separated substrate and a second separated substrate, said separation starting from an internal plane modified layer formed in an in-plane direction of the interior of the substrate; a machining section for respectively grinding a separation surface of the first separated substrate and a separation surface of the second separated substrate; a conveyance mechanism for conveying the substrate to at least the separating section or the machining section; and an inversion mechanism for inverting the front and rear faces of the second separated substrate.

Description

Substrate processing system and substrate processing method

The present disclosure relates to a substrate processing system and a substrate processing method.

Patent Document 1 discloses a method of processing a wafer having a plurality of devices formed on a front surface side. In this processing method, after the deteriorated layer is formed by irradiating a laser beam between the front side and the back side of the wafer, the back side wafer on the back side of the deteriorated layer and the front side wafer on the front side of the deteriorated layer are formed. And separated into Further, the back side wafer is recycled.

JP 2010-21398 A

技術 The technology according to the present disclosure efficiently separates and regenerates the substrate when separating and thinning the substrate and reusing the separated substrate.

One embodiment of the present disclosure is a substrate processing system for processing a substrate, the substrate being separated from a first separation substrate and a second separation substrate starting from an internal surface modification layer formed in a surface direction inside the substrate. A separation unit for separating the substrate, a processing unit for grinding the separation surface of the first separation substrate and a separation surface of the second separation substrate, and the substrate for at least the separation unit or the processing unit. It has a transport mechanism for transporting, and a reversing mechanism for reversing the front and back surfaces of the second separation substrate.

According to the present disclosure, when the substrate is separated and thinned, and the separated substrate is reused, the separation and the regeneration can be efficiently performed.

FIG. 1 is a plan view schematically showing an outline of a configuration of a wafer processing system according to an embodiment. It is a side view which shows the outline of a structure of a superposition wafer. It is a side view which shows the outline of a part of structure of a superposition wafer. It is a side view which shows the outline of a structure of a reforming separation apparatus. It is a flowchart which shows the main process of the wafer processing concerning this embodiment. FIG. 4 is an explanatory diagram of main steps of wafer processing according to the embodiment. It is a longitudinal cross-sectional view which shows a mode that an internal surface modification layer is formed on a processing wafer in a modification separation apparatus. It is a top view showing signs that an internal surface modification layer is formed in a processing wafer in a modification separation device. It is explanatory drawing which shows a mode that a process wafer is isolate | separated in a reforming separation apparatus. It is explanatory drawing which shows a mode that a separation surface of a separation wafer is ground in a processing apparatus. It is explanatory drawing which shows a mode that a separation surface of a separation wafer is ground in a processing apparatus. It is a top view which shows typically the outline of the structure of the wafer processing system concerning other embodiment. It is a top view which shows typically the outline of the structure of the wafer processing system concerning other embodiment. It is a side view which shows the outline of a structure of a separation inversion unit. It is a side view which shows the outline of a structure of the transfer arm of a wafer transfer apparatus. It is a side view which shows the outline of a structure of the transfer arm of a wafer transfer apparatus. It is a flowchart which shows the main process of the wafer processing concerning other embodiment. It is an explanatory view of a main step of wafer processing according to another embodiment. It is explanatory drawing which shows a mode that a peripheral edge modification layer is formed in a process wafer in another embodiment. It is an explanatory view of a main step of wafer processing according to another embodiment. It is an explanatory view of a main step of wafer processing according to another embodiment. It is explanatory drawing which shows a mode that a periphery modification layer and a division | segmentation modification layer are formed in a process wafer in another embodiment. It is explanatory drawing which shows a mode that a periphery modification layer and a division | segmentation modification layer are formed in a process wafer in another embodiment. It is explanatory drawing which shows a mode that the peripheral part of a process wafer is removed in another embodiment.

In a semiconductor device manufacturing process, a semiconductor wafer having a plurality of devices formed on its surface (hereinafter, referred to as a wafer) is thinned. There are various methods for thinning a wafer. For example, there are a method of grinding the back surface of the wafer and a method of separating the wafer as disclosed in Patent Document 1. In particular, according to the method disclosed in Patent Literature 1, the device constituting the separated front side wafer can be commercialized, and the back side wafer can be recycled.

Here, the altered layer (modified layer) remains on the front surface of the separated rear wafer, and cannot be recycled (reused) as it is. However, Patent Document 1 does not disclose or suggest how to treat the modified layer of the backside wafer. Furthermore, no method is considered at all for a method of efficiently reusing the backside wafer. Accordingly, there is room for improvement in conventional wafer processing in separating and thinning wafers and reusing the separated wafers.

技術 The technology according to the present disclosure efficiently separates a wafer and reuses the separated wafer. Hereinafter, a wafer processing system as a substrate processing system and a wafer processing method as a substrate processing method according to the present embodiment will be described with reference to the drawings. In the specification and the drawings, elements having substantially the same function and structure are denoted by the same reference numerals, and redundant description is omitted.

First, the configuration of the wafer processing system according to the present embodiment will be described. FIG. 1 is a plan view schematically showing the outline of the configuration of the wafer processing system 1.

In the wafer processing system 1, as shown in FIGS. 2 and 3, desired processing is performed on a superposed wafer T in which a processing wafer W as a substrate and a supporting wafer S are joined, and the processing wafer W is separated and thinned. Become Hereinafter, in the processing wafer W, a surface bonded to the support wafer S is referred to as a front surface Wa, and a surface opposite to the front surface Wa is referred to as a back surface Wb. Similarly, in the support wafer S, the surface bonded to the processing wafer W is referred to as a front surface Sa, and the surface opposite to the front surface Sa is referred to as a back surface Sb.

The processing wafer W is a semiconductor wafer such as a silicon wafer, for example, and a device layer D including a plurality of devices is formed on a surface Wa. Further, an oxide film Fw, for example, an SiO ₂ film (TEOS film) is further formed on the device layer D. The periphery of the processing wafer W is chamfered, and the cross section of the periphery decreases in thickness toward its front end.

The support wafer S is a wafer that supports the processing wafer W, and is, for example, a silicon wafer. An oxide film Fs, for example, an SiO ₂ film (TEOS film) is formed on the surface Sa of the support wafer S. Further, the support wafer S functions as a protective material for protecting devices on the surface Wa of the processing wafer W. When a plurality of devices on the surface Sa of the support wafer S are formed, a device layer (not shown) is formed on the surface Sa, similarly to the processing wafer W.

Note that, in FIG. 2, the device layer D and the oxide films Fw and Fs are not shown in order to avoid complications. Similarly, in other drawings used in the following description, the illustration of the device layer D and the oxide films Fw and Fs may be omitted.

In addition, in the wafer processing system 1 of the present embodiment, the processing wafer W in the overlapped wafer T is separated. In the following description, the separated processing wafer W on the front surface Wa is referred to as a first separation wafer W1 as a first separation substrate, and the separated processing wafer W on the rear surface Wb is referred to as a second separation substrate. Of the second separated wafer W2. The first separation wafer W1 has a device layer D and is commercialized. The second separation wafer W2 is reused. Note that the first separated wafer W1 refers to the processing wafer W supported by the support wafer S, and may be referred to as the first separated wafer W1 including the support wafer S. The surface separated on the first separation wafer W1 is called a separation surface W1a, and the surface separated on the second separation wafer W2 is called a separation surface W2a.

ウェハ As shown in FIG. 1, the wafer processing system 1 has a configuration in which the carry-in / out station 2 and the processing station 3 are integrally connected. The loading / unloading station 2 and the processing station 3 are arranged side by side from the X axis positive direction side to the negative direction side. The carry-in / out station 2 carries in and out cassettes Ct, Cw1, and Cw2 capable of accommodating, for example, a plurality of overlapped wafers T, a plurality of first separated wafers W1, and a plurality of second separated wafers W2 with the outside. It is. The processing station 3 includes various processing apparatuses that perform desired processing on the overlapped wafer T and the separated wafers W1 and W2.

The cassette loading table 10 is provided at the loading / unloading station 2. In the illustrated example, a plurality of, for example, three cassettes Ct, Cw1, and Cw2 can be mounted on the cassette mounting table 10 in a line in the Y-axis direction. In addition, the number of the cassettes Ct, Cw1, and Cw2 mounted on the cassette mounting table 10 is not limited to the present embodiment, and can be arbitrarily determined.

(4) In the loading / unloading station 2, a wafer transfer area 20 is provided adjacent to the cassette mounting table 10 on the negative side of the cassette mounting table 10 in the X-axis direction. The wafer transfer area 20 is provided with a wafer transfer device 22 movable on a transfer path 21 extending in the Y-axis direction. The wafer transfer device 22 has two

transfer arms

23, 23 for holding and transferring the overlapped wafer T and the separated wafers W1, W2. Each transfer arm 23 is configured to be movable in a horizontal direction (X-axis direction and Y-axis direction), a vertical direction, around a horizontal axis, and around a vertical axis. Note that the configuration of the transfer arm 23 is not limited to the present embodiment, and may have any configuration.

The processing station 3 is provided with, for example, three processing blocks G1 to G3 and a wafer transfer area 30. The first processing block G1, the second processing block G2, and the third processing block G3 are arranged in this order from the X-axis negative direction side (the loading / unloading station 2 side) to the positive direction side. The first processing block G1 is disposed on the X-axis positive direction side of the wafer transfer area 30, and the second processing block G2 and the third processing block G3 are disposed on the Y-axis positive direction side of the wafer transfer area 30, respectively. I have.

The wafer transfer area 30 is provided with a wafer transfer device 32 that is movable on a transfer path 31 extending in the X-axis direction and that functions as a transfer mechanism. The wafer transfer device 32 is configured to be able to transfer the overlapped wafer T and the separated wafers W1 and W2 to the respective processing devices of the processing blocks G1 to G3. The wafer transfer device 32 has two

transfer arms

33, 33 for holding and transferring the overlapped wafer T and the separated wafers W1, W2. As an example, the first transfer arm 33 holds the overlapped wafer T and the separation wafers W1 and W2 from below, and the second transfer arm 33 holds the overlapped wafer T and the separation wafers W1 and W2 from above. Each transfer arm 33 is supported by a multi-joint arm member 34 and is configured to be movable in a horizontal direction, a vertical direction, around a horizontal axis, and around a vertical axis. Note that the configuration of the transfer arm 33 is not limited to the present embodiment, and may have any configuration.

(2) The first processing block G1 is provided with two

wet etching devices

40 and 41, an alignment device 50, and two cleaning devices 51 and 52. The

wet etching devices

40 and 41 are stacked in this order from above on the Y axis positive direction side. The alignment device 50 and the two cleaning devices 51 and 52 are stacked in this order from above on the Y-axis negative direction side.

{Circle around (2)} In the second processing block G2, a reversing device 60 and a reforming / separating device 61 are stacked in this order from above. The reversing device 60 constitutes a reversing mechanism according to the present disclosure. In addition, the reforming separation device 61 is configured to serve both as the separation unit and the internal surface reforming unit according to the present disclosure.

加工 A processing device 70 as a processing unit is provided in the third processing block G3. The number and arrangement of the processing devices 70 are not limited to this embodiment, and a plurality of processing devices 70 may be arbitrarily arranged. When a plurality of processing devices 70 are provided, a plurality of wafer transfer devices 32 may be provided in the wafer transfer region 30.

The

wet etching devices

40 and 41 respectively etch the separation surfaces W1a and W2a of the separation wafers W1 and W2 ground by the processing device 70. For example, a chemical solution (etching solution) is supplied to each of the separation surfaces W1a and W2a of the separation wafers W1 and W2. In addition, HF, HNO ₃ , H ₃ PO ₄ , TMAH, Choline, KOH, or the like is used as the chemical solution, for example.

The alignment device 50 adjusts the horizontal direction of the overlapped wafer T before processing. For example, by detecting the position of the notch of the processing wafer W by the detection unit (not shown) while rotating the overlapped wafer T held by the chuck (not shown), the position of the notch is adjusted. The horizontal direction of the overlapped wafer T is adjusted.

The cleaning devices 51 and 52 clean the respective separation surfaces W1a and W2a of the separation wafers W1 and W2 ground by the processing device 70, respectively. For example, a brush is brought into contact with the separation surfaces W1a and W2a to scrub the separation surfaces W1a and W2a. Note that a pressurized cleaning liquid may be used for cleaning the separation surfaces W1a and W2a.

The reversing device 60 reverses the front and back surfaces of the second separation wafer W2 separated by the reforming separation device 61. The configuration of the reversing device 60 is arbitrary.

The reforming / separating device 61 irradiates the inside of the processing wafer W with a laser beam to form an internal surface modified layer described later, and further starts the processing wafer W from the internal surface modified layer as a first separation wafer. The wafer is separated into W1 and a second separation wafer W2.

(4) The reforming / separating apparatus 61 has a chuck 80 for holding the overlapped wafer T in a state where the processing wafer W is located on the upper side and the supporting wafer S is located on the lower side as shown in FIG. The chuck 80 is configured to be movable in the X-axis direction and the Y-axis direction by the moving unit 81. The moving unit 81 includes a general precision XY stage. The chuck 80 is configured to be rotatable around a vertical axis by a rotating unit 82.

レーザ Above the chuck 80, a laser head 90 as an internal surface reforming unit for irradiating the inside of the processing wafer W with laser light is provided. The laser head 90 emits high-frequency pulsed laser light oscillated from a laser light oscillator (not shown) and having a wavelength that is transparent to the processing wafer W inside the processing wafer W. The light is condensed and irradiated at a desired position. As a result, the portion where the laser light is focused inside the processing wafer W is modified, and an internal surface modified layer is formed. Further, the laser head 90 irradiates the laser light from the laser light oscillator into a plurality of laser beams at the same time, for example, with a lens or the like. In such a case, a plurality of laser beams are emitted from the laser head 90, and a plurality of internal surface modification layers are simultaneously formed inside the processing wafer W. The laser head 90 is configured to be movable in the X-axis direction and the Y-axis direction by the moving unit 91. The moving unit 91 includes a general precision XY stage. The laser head 90 is configured to be movable in the Z-axis direction by an elevating unit 92.

(4) Above the chuck 80, a suction pad 100 that holds the back surface Wb of the processing wafer W by suction is provided. The suction pad 100 is configured to be rotatable around a vertical axis by a rotating unit 101. Further, the suction pad 100 is configured to be movable in the Z-axis direction by the elevating unit 102.

加工 As shown in FIG. 1, the processing apparatus 70 grinds the separation surface W1a of the first separation wafer W1 and the separation surface W2a of the second separation wafer W2. The processing device 70 has a rotary table 110, a first grinding unit 120, and a second grinding unit 130.

The rotary table 110 is configured to be rotatable around a vertical rotation center line 111 by a rotation mechanism (not shown). On the rotary table 110, four chucks 112 are provided as holding units for sucking and holding the separated wafers W1 and W2. The chucks 112 are evenly arranged on the same circumference as the rotary table 110, that is, are arranged at intervals of 90 degrees. The four chucks 112 can be moved to the delivery positions A1, A2 and the processing positions B1, B2 by rotating the rotary table 110. Note that the chuck 112 is held by a chuck base (not shown) and is configured to be rotatable by a rotation mechanism (not shown).

In the present embodiment, the first delivery position A1 is a position on the X-axis negative direction side and the Y-axis negative direction side of the turntable 110, and the first separated wafer W1 is delivered. The second transfer position A2 is a position on the X-axis positive direction side and the Y-axis negative direction side of the turntable 110, and the second separated wafer W2 is transferred. The first processing position B1 is a position on the X-axis positive direction side and the Y-axis positive direction side of the turntable 110, and the first grinding unit 120 is disposed. The second processing position B2 is a position on the X-axis negative direction side and the Y-axis positive direction side of the rotary table 110, and the second grinding unit 130 is disposed.

１ The first grinding unit 120 grinds the separation surface W1a of the first separation wafer W1. The first grinding unit 120 has a first grinding unit 121 provided with an annular and rotatable grinding wheel (not shown). Further, the first grinding unit 121 is configured to be movable in the vertical direction along the column 122. Then, while the separation surface W1a of the first separation wafer W1 held by the chuck 112 is in contact with the grinding wheel, the chuck 112 and the grinding wheel are respectively rotated, and the grinding wheel is further lowered, whereby the first The separation surface W1a of the separation wafer W1 is ground. Thus, the internal surface modified layer remaining on the separation surface W1a of the first separation wafer W1 is removed.

では In the second grinding unit 130, the separation surface W2a of the second separation wafer W2 is ground. The second grinding unit 130 has a second grinding unit 131 provided with an annular and rotatable grinding wheel (not shown). Further, the second grinding portion 131 is configured to be movable in the vertical direction along the column 132. Then, in a state where the separation surface W2a of the second separation wafer W2 held by the chuck 112 is in contact with the grinding wheel, the chuck 112 and the grinding wheel are rotated, and the grinding wheel is further lowered. The separation surface W2a of the separation wafer W2 is ground. Thus, the internal surface modified layer remaining on the separation surface W2a of the second separation wafer W2 is removed.

制御 A control device 140 is provided in the wafer processing system 1 described above. The control device 140 is, for example, a computer and has a program storage unit (not shown). The program storage section stores a program for controlling the processing of the overlapped wafer T in the wafer processing system 1. The program storage unit also stores programs for controlling operations of driving systems such as the above-described various types of processing apparatuses and transfer apparatuses so as to realize the below-described substrate processing in the wafer processing system 1. Note that the program may be recorded on a storage medium H that can be read by a computer, and may be installed on the control device 140 from the storage medium H.

Next, wafer processing performed using the wafer processing system 1 configured as described above will be described. FIG. 5 is a flowchart showing main steps of wafer processing. In the present embodiment, the processing wafer W and the supporting wafer S are bonded by van der Waals force and hydrogen bonding (intermolecular force) in a bonding apparatus (not shown) outside the wafer processing system 1, and a superposed wafer is previously formed. T is formed.

First, the cassette Ct storing a plurality of overlapped wafers T shown in FIG. 6A is mounted on the cassette mounting table 10 of the loading / unloading station 2.

(4) Next, the overlapped wafer T in the cassette Ct is taken out by the wafer transfer device 22 and transferred to the alignment device 50. In the alignment device 50, the horizontal direction of the overlapped wafer T (processed wafer W) is adjusted (Step P1 in FIG. 5).

Next, the overlapped wafer T is transferred to the reforming / separating device 61 by the wafer transfer device 32. In the reforming separation device 61, the internal surface reforming layer M1 is formed inside the processing wafer W as shown in FIG. 6B (Step P2 in FIG. 5).

(7) As shown in FIG. 7, the inside of the processing wafer W is irradiated with laser light L from the laser head 90 to form the internal surface modified layer M1. The internal surface modification layer M1 extends in the surface direction and has a horizontally long aspect ratio. The lower end of the internal surface modified layer M1 is located slightly above the target surface (dotted line in FIG. 7) of the processed wafer W after grinding. That is, the distance H1 between the lower end of the internal surface modification layer M1 and the surface Wa of the processing wafer W is slightly larger than the target thickness H2 of the processing wafer W after grinding. The internal surface modified layer M1 has a vertically long aspect ratio, and the plurality of internal surface modified layers M1 may be arranged with a small pitch. Further, cracks C1 propagate from the inner surface modified layer M1 in the surface direction. Further, when the pitch of the internal surface modification layer M1 is small, the crack C1 may not be provided.

Then, as shown in FIGS. 7 and 8, the laser head 90 and the overlapped wafer T are relatively horizontally moved to form a plurality of internal surface modified layers M1 inside the processing wafer W. Specifically, first, the laser head 90 is moved in the X-axis direction to form a row of internal surface modification layers M1. Thereafter, the laser head 90 is shifted in the Y-axis direction, and the laser head 90 is further moved in the X-axis direction to form another row of the internal surface modified layer M1. The plurality of inner surface modification layers M1 are formed at the same height. Then, an internal surface modified layer M1 is formed on the entire internal surface of the processing wafer W.

In the modification / separation device 61, a plurality of laser beams L may be simultaneously irradiated from the laser head 90. In this case, the internal surface modification layer M1 can be formed in a shorter time, and the throughput of wafer processing can be improved. In the modification / separation device 61, the laser head 90 may be moved in the horizontal direction while rotating the chuck 80. In such a case, the internal surface modification layer M1 is formed in a spiral shape in plan view. Then, the pitch of the plurality of internal surface modification layers M1 may be changed in the concentric direction and the radial direction of the processing wafer W.

Next, in the same reforming separation apparatus 61, the processing wafer W is separated into a first separation wafer W1 and a second separation wafer W2 based on the internal surface reforming layer M1 as shown in FIG. 6C. (Step P3 in FIG. 5).

裏面 As shown in FIG. 9A, the back surface Wb of the processing wafer W is suction-held by the suction pad 100. Then, by rotating the suction pad 100, the first separation wafer W1 and the second separation wafer W2 are cut off at the boundary of the inner surface modified layer M1. Thereafter, as shown in FIG. 9B, in a state where the suction pad 100 sucks and holds the second separation wafer W2, the suction pad 100 is raised to move the second separation wafer W2 from the first separation wafer W1. Is separated. The internal surface modified layer M1 remains on each of the separation surface W1a of the first separation wafer W1 and the separation surface W2a of the second separation wafer W2.

The method for separating the processing wafer W is not limited to the present embodiment. When the second separation wafer W2 can be separated simply by raising the suction pad 100 as shown in FIG. 9B, the rotation of the suction pad 100 shown in FIG. 9B may be omitted. Further, for example, a tape (not shown) may be used instead of the suction pad 100, and the processing wafer W may be held and separated by the tape. Further, before the processing wafer W is suction-held by the suction pad 100, ultrasonic waves may be applied to at least the internal surface modified layer M1 of the processed wafer W, or by heating the internal surface modified layer M1. Is also good. In such a case, it becomes easy to separate the processing wafer W based on the inner surface modified layer M1.

Next, the second separation wafer W2 is transferred to the reversing device 60 by the wafer transfer device 32. In the reversing device 60, the front and back surfaces of the second separation wafer W2 are reversed (Step P4 in FIG. 5). Thereafter, the second separated wafer W2 is transferred to the processing device 70 by the wafer transfer device 32, and is transferred to the chuck 112 at the second transfer position A2 as shown in FIG.

In parallel with Step P4, the first separated wafer W1 is transferred to the processing device 70 by the wafer transfer device 32, and transferred to the chuck 112 at the first transfer position A1 as shown in FIG.

Next, as shown in FIG. 10B, the rotary table 110 is rotated 180 ° counterclockwise to move the first separated wafer W1 to the first processing position B1, and to move the second separated wafer W2. It is moved to the second processing position B2.

Next, at the first processing position B1, as shown in FIG. 6D, the separation surface W1a of the first separation wafer W1 is ground, and the internal surface modification layer M1 remaining on the separation surface W1a is removed. At the same time, at the second processing position B2, as shown in FIG. 6E, the separation surface W2a of the second separation wafer W2 is ground to remove the internal surface modified layer M1 remaining on the separation surface W2a (FIG. Step P5).

Next, the rotary table 110 is rotated counterclockwise by 180 ° to move the first separated wafer W1 to the first transfer position A1 in the state shown in FIG. W2 is moved to the second delivery position A2. At the first delivery position A1, the separation surface W1a of the first separation wafer W1 may be cleaned with the cleaning liquid using a cleaning liquid nozzle (not shown). Also at the second delivery position A2, the separation surface W2a of the second separation wafer W2 may be cleaned with the cleaning liquid using a cleaning liquid nozzle (not shown).

Next, the first separated wafer W1 is transferred to the cleaning device 51 by the wafer transfer device 32, and the second separated wafer W2 is transferred to the cleaning device 52 by the wafer transfer device 32. In the cleaning device 51, the separation surface W1a of the first separation wafer W1 is scrub-cleaned, and in the cleaning device 52, the separation surface W2a of the second separation wafer W2 is scrub-cleaned (Step P6 in FIG. 5).

Next, the first separated wafer W1 is transferred to the wet etching device 40 by the wafer transfer device 22, and the second separated wafer W2 is transferred to the wet etching device 41 by the wafer transfer device 22. In the wet etching device 40, the separation surface W1a of the first separation wafer W1 is wet-etched with a chemical, and in the wet etching device 41, the separation surface W2a of the second separation wafer W2 is wet-etched with a chemical (step P7 in FIG. 5). Grinding marks may be formed on each of the separation surfaces W1a and W2a ground by the processing device 70 described above. In the present step P7, grinding marks can be removed by wet etching, and the separation surfaces W1a and W2a can be smoothed.

After that, the first separated wafer W1 and the second separated wafer W2 that have been subjected to all the processes are respectively transferred to the cassettes Cw1 and Cw2 of the cassette mounting table 10 by the wafer transfer device 22. Thus, a series of wafer processing in the wafer processing system 1 ends.

According to the above embodiment, steps P1 to P7 can be performed to separate the processing wafer W, and the separation surfaces W1a and W2a of the separation wafers W1 and W2 can be appropriately processed by grinding, wet etching, or the like. Therefore, it is possible to commercialize the first separation wafer W1 having the device layer D and reuse the second separation wafer W2. In addition, since these steps P1 to P7 are performed by one wafer processing system 1, wafer processing can be performed efficiently.

In addition, since the processing apparatus 70 of the present embodiment includes the rotary table 110, the first grinding unit 120, and the second grinding unit 130, the grinding of the separation surface W1a of the first separation wafer W1 in Step P5. And the grinding of the separation surface W2a of the second separation wafer W2 can be performed in parallel. Therefore, the throughput of the wafer processing can be improved.

The processing device 70 of the present embodiment is provided with delivery positions A1, A2 and processing positions B1, B2 corresponding to the four chucks 112 of the rotary table 110. Then, for example, as shown in FIG. 11, grinding of the separation surface W1a at the first processing position B1 and delivery of the first separation wafer W1 at the first delivery position A1 can be performed in parallel. Similarly, grinding of the separation surface W2a at the second processing position B2 and delivery of the second separation wafer W2 at the second delivery position A2 can be performed in parallel. Therefore, the throughput of the wafer processing can be improved.

In addition, since the processing device 70 of the present embodiment is provided with the delivery positions A1 and A2 and the processing positions B1 and B2, for example, when two rotary tables provided with one delivery position and one processing position are used. The number of use of the rotary table is smaller than that of. As a result, the occupied area (footprint) of the processing apparatus 70 can be reduced, and the occupied area of the wafer processing system 1 can be reduced.

Further, in this embodiment, in thinning the processing wafer W, after forming the internal surface modified layer M1 inside the processing wafer W in step P2, in step P3, the processing wafer is formed based on the internal surface modified layer M1. W is separated. For example, when the back surface Wb of the processing wafer W is ground and thinned as in the related art, a grinding wheel is worn and grinding water is used. On the other hand, in the present embodiment, the degree of deterioration of the laser head 90 itself with time is small and consumables are reduced, so that the maintenance frequency can be reduced. In addition, since it is a dry process using a laser, grinding water and wastewater treatment are not required. Therefore, the running cost can be reduced. Furthermore, since the grinding water does not flow to the support wafer S side, it is possible to suppress the support wafer S from being contaminated.

Also, in the present embodiment, the separation surface W1a is ground in step P5, but this grinding may be performed by removing the inner surface modified layer M1, and the grinding amount is as small as several tens of μm. On the other hand, when the back surface Wb is ground in order to thin the processing wafer W as in the related art, the grinding amount is as large as 700 μm or more, for example, and the degree of wear of the grinding wheel is large. For this reason, in the present embodiment, the maintenance frequency can be reduced as well.

In the case where a plurality of processing apparatuses 70 are provided in the wafer processing system 1 of the present embodiment, one processing apparatus 70 grinds the separation surface W1a of the first separation wafer W1 and another processing apparatus 70 The separation surface W2a of the separation wafer W2 may be ground.

Next, another embodiment of the wafer processing system will be described.

FIG. 12 is a plan view schematically showing a schematic configuration of a wafer processing system 200 according to another embodiment. In the wafer processing system 200, the formation of the internal surface modified layer M1 and the separation of the processed wafer W in the reforming and separating apparatus 61 of the wafer processing system 1 of the above embodiment are performed by separate apparatuses. That is, the wafer processing system 200 includes a separation / inversion device 201 and a reforming device 202 instead of the reversing device 60 and the reforming / separating device 61 of the wafer processing system 1. The separation inversion device 201 and the reforming device 202 are provided in this order in the second processing block G2 from above.

(4) The reforming apparatus 202 forms the internal surface modified layer M1 inside the processing wafer W. The reforming device 202 includes, for example, a member (such as the laser head 90) for forming the internal surface reformed layer M1 in the configuration of the reforming separation device 61. The separation reversing device 201 separates the processing wafer W from the internal surface modified layer M1 as a base point, and reverses the front and back surfaces of the separated second separation wafer W2. The separation and inversion device 201 has, for example, a configuration of the inversion device 60 in addition to a member (the suction pad 100 and the like) for separating the processing wafer W in the configuration of the reforming and separation device 61.

でも The wafer processing system 200 of this embodiment can also perform the steps P1 to P7 of the above embodiment, and can enjoy the same effects as those of the embodiment.

FIG. 13 is a plan view schematically showing the outline of the configuration of a wafer processing system 300 according to another embodiment. The wafer processing system 300 separates the processing wafer W in the reforming / separating device 61 of the wafer processing system 1 of the above embodiment and inverts the front and back surfaces of the second separated wafer W2 in the reversing device 60 inside the processing device 70. Is what you do. That is, the wafer processing system 300 includes a reforming device 301 and a separation / reversing unit 302 instead of the reversing device 60 and the reforming / separating device 61 of the wafer processing system 1.

The reformer 301 is provided in the second processing block G2. The reforming apparatus 301 forms the internal surface reforming layer M1 inside the processing wafer W. The reforming device 202 includes, for example, a member (such as the laser head 90) for forming the internal surface reformed layer M1 in the configuration of the reforming separation device 61.

The separation / reversal unit 302 is provided above the turntable 110 and the chuck 112 at the second delivery position A2 of the processing device 70. The separation / reversal unit 302 includes a separation mechanism 303 for separating the processing wafer W from the internal surface modified layer M1 as a base point, and a reversing mechanism 304 for reversing the front and back surfaces of the separated second separation wafer W2. .

As shown in FIG. 14, the separation mechanism 303 has a suction pad 310 that suction-holds the back surface Wb of the processing wafer W to the overlapped wafer T held by the chuck 112. The suction pad 310 is configured to be rotatable around a vertical axis by a rotating unit 311. Further, the suction pad 310 is configured to be movable in the Z-axis direction by the elevating unit 312. Then, in the separation mechanism 303, first, in a state where the back surface Wb of the processing wafer W is suction-held by the suction pad 310, the suction pad 310 is rotated, and the first separation wafer W1 and the first separation wafer W1 are separated with the internal surface modified layer M1 as a boundary. The second separation wafer W2 is cut off. Thereafter, with the suction pad 310 holding the second separation wafer W2 by suction, the suction pad 100 is raised to separate the second separation wafer W2 from the first separation wafer W1.

The reversing mechanism 304 has a holding unit 320 that holds the second separation wafer W2. The method of holding the second separated wafer W2 by the holding unit 320 is not particularly limited, but is, for example, suction holding. The holding unit 320 is configured to be rotatable around a horizontal axis by a rotating unit 321. The holding unit 320 is configured to be movable in the Z-axis direction by the elevating unit 322. Then, in the reversing mechanism 304, while the second separation wafer W2 is being held by the holding unit 320, the holding unit 320 is rotated around a horizontal axis to invert the front and back surfaces of the second separation wafer W2.

In such a case, in Step P2, the internal surface reforming layer M1 is formed inside the processing wafer W in the reforming apparatus 301. Thereafter, the processing wafer W is transferred to the processing device 70 by the wafer transfer device 32 in a state of being supported by the support wafer S, that is, in a state of the overlapped wafer T. In the processing device 70, the overlapped wafer T is delivered to the chuck 112 at the second delivery position A2.

Next, in step P3, the processing wafer W is separated into the separation wafers W1 and W2 by the separation mechanism 303 while the chuck 112 holds the overlapped wafer T. Thereafter, in Step P4, the separated second separated wafer W2 is transferred to the holding unit 320 of the reversing mechanism 304, and the holding unit 320 is rotated around a horizontal axis so that the front and back surfaces of the second separated wafer W2 are Inverted. Then, the first separated wafer W1 is transported to the chuck 112 at the first delivery position A1, and the second separated wafer W2 is held as it is by the chuck 112 at the second delivery position A2. The transfer of the first separated wafer W1 may be performed by the wafer transfer device 32. Alternatively, while the front and back surfaces of the second separation wafer W2 are being inverted by the reversing mechanism 304, the rotary table 110 is rotated to move the first separation wafer W1 from the second delivery position A2 to the first delivery position A1. It may be transported.

The other steps P1, P5 to P7 are the same as those in the above embodiment. In the wafer processing system 300 of the present embodiment, the same effects as in the above embodiment can be enjoyed.

The

wafer processing systems

1, 200, and 300 of the above embodiments may have a CMP device (CMP: Chemical Mechanical Polishing, chemical mechanical polishing) instead of the

wet etching devices

40 and 41. This CMP apparatus functions similarly to the

wet etching apparatuses

40 and 41. That is, in the CMP apparatus, the separation surfaces W1a and W2a ground by the processing apparatus 70 are polished. Then, the processing device 70 removes grinding marks formed on the separation surfaces W1a and W2a, and smoothes the separation surfaces W1a and W2a. Note that the

wafer processing systems

1, 200, and 300 may include both

wet etching devices

40 and 41 and a CMP device, and perform both wet etching and CMP on the separation surfaces W1a and W2a.

In the

wafer processing systems

1, 200, and 300 of the above embodiments, the reversing device 60, the separating / reversing device 201, and the separating / reversing unit 302 reverse the front and back surfaces of the second separated wafer W2. In the transfer arm 33 of the device 32, the front and back surfaces of the second separation wafer W2 may be reversed. In such a case, as shown in FIG. 15, the transfer arm 33 supported by the arm member 34 rotates around the horizontal axis, and the front and back of the second separation wafer W2 are inverted.

{Circle around (2)} Although the wafer transfer device 32 has two transfer arms 33, one transfer arm 400 may hold and transfer two separated wafers W1 and W2 as shown in FIG. A suction pad 401 for sucking and holding the first separated wafer W1 is provided on one surface of the transfer arm 400, and a suction pad 402 for sucking and holding the second separated wafer W2 on the other surface. The transfer arm 400 is supported by the arm member 34 and is configured to be rotatable around a horizontal axis.

In the

wafer processing systems

1, 200, and 300 of the above embodiments, the reforming / separating device 61 and the reforming

devices

202 and 301 respectively form the internal surface modified layer M1 inside the processing wafer W. The processing may be performed by the

processing systems

1, 200, and 300. In such a case, the internal surface modification layer M1 is formed in advance inside the processing wafer W transferred to the

wafer processing system

1, 200, 300.

Here, usually, the peripheral portion of the processing wafer W is chamfered. For example, when the back surface Wb of the processing wafer W is ground and thinned as in the related art, the peripheral portion of the processing wafer W is sharply pointed. Shape (so-called knife edge shape). Then, chipping occurs at the peripheral portion of the processing wafer W, and the processing wafer W may be damaged. Therefore, so-called edge trimming, in which the peripheral portion of the processing wafer W is removed in advance before the grinding process, is performed.

Therefore, edge trim may be performed in the

wafer processing systems

1, 200, and 300 of the above embodiments. In the following description, a case where edge trimming is performed in the wafer processing system 1 will be described.

エッジ In the wafer processing system 1, edge trimming is performed in the reforming / separating device 61. That is, in the reforming separation apparatus 61, a peripheral reforming layer is formed in the thickness direction along the boundary between the peripheral portion and the central portion of the processing wafer W, and the peripheral portion of the processing wafer W is removed based on the peripheral reforming layer. I do. In the reforming separation device 61 of the present embodiment, the laser head 90 functions as a peripheral reforming section, and forms a peripheral reforming layer inside the processing wafer W.

Next, wafer processing according to another embodiment, which is performed using the wafer processing system 1, will be described. FIG. 17 is a flowchart showing main steps of wafer processing. In the present embodiment, detailed description of the same processes as those in the embodiment shown in FIG. 5 is omitted.

First, as shown in FIG. 18A, a cassette Ct containing a plurality of overlapped wafers T is mounted on the cassette mounting table 10 of the loading / unloading station 2.

(4) Next, the overlapped wafer T in the cassette Ct is taken out by the wafer transfer device 22 and transferred to the alignment device 50. In the alignment apparatus 50, the horizontal direction of the overlapped wafer T (processed wafer W) is adjusted (Step Q1 in FIG. 17).

Next, the overlapped wafer T is transferred to the reforming / separating device 61 by the wafer transfer device 32. In the reforming separation device 61, a peripheral reforming layer M2 is formed inside the processing wafer W as shown in FIG. 18B (step Q2 in FIG. 17).

In the reforming separation apparatus 61, as shown in FIG. 19, the laser head 90 is moved to a position above the processing wafer W and to a boundary between the peripheral edge portion We and the central portion Wc of the processing wafer W. Thereafter, the laser head 90 irradiates the inside of the processing wafer W with the laser beam L while rotating the chuck 80 by the rotating unit 82. Then, along the boundary between the peripheral edge portion We and the central portion Wc, an annular peripheral edge modified layer M2 is formed.

The peripheral edge modified layer M2 is a base point for removing the peripheral edge We in the edge trim, and is formed in an annular shape along the boundary between the peripheral edge We to be removed and the central portion Wc in the processing wafer W. You. The peripheral edge portion We is, for example, in a range of 1 mm to 5 mm in the radial direction from the outer end of the processing wafer W, and includes a chamfered portion.

{Circle around (2)} The peripheral edge modified layer M2 extends in the thickness direction and has a vertically long aspect ratio. The lower end of the peripheral edge modified layer M2 is located above the target surface (the dotted line in FIG. 19) of the processed wafer W after the grinding. That is, the distance H3 between the lower end of the peripheral edge modified layer M2 and the surface Wa of the processing wafer W is larger than the target thickness H2 of the processing wafer W after grinding. In such a case, the peripheral modified layer M2 does not remain on the processed wafer W after the grinding.

{Circle around (4)} Cracks C2 further extend from the peripheral modified layer M2 into the inside of the processed wafer W and reach the surface Wa. However, the crack C2 has not reached the back surface Wb.

Next, in the same reforming separation apparatus 61, an internal surface reforming layer M3 is formed inside the processing wafer W as shown in FIG. 18C (Step Q3 in FIG. 17). Similar to the internal surface modified layer M1 shown in FIG. 6, the internal surface modified layer M3 extends in the surface direction of the processing wafer W. The internal surface modified layer M3 is formed at the same height as the peripheral edge modified layer M2, and the lower end of the internal surface modified layer M3 is located above the target surface of the processed wafer W after the grinding. Then, a plurality of internal surface modified layers M3 are formed in the surface direction, and the plurality of internal surface modified layers M3 are formed in the surface direction from the central portion to the peripheral edge modified layer M2, that is, in the central portion Wc. The method for forming the inner surface modified layer M3 is the same as that in Step P2. Further, cracks C3 propagate from the inner surface modified layer M3 in the surface direction. Further, when the pitch of the internal surface modification layer M3 is small, the crack C3 may not be provided.

Next, in the same reforming separation apparatus 61, as shown in FIG. 18D, the processing wafer W is divided into the first separation wafer W1 and the second separation wafer W1 based on the inner surface reforming layer M3 and the peripheral reforming layer M2. The wafer is separated into separated wafers W2 (Step Q4 in FIG. 17). At this time, since the inner surface modified layer M3 and the peripheral edge modified layer M2 are formed at the same height, the second separation wafer W2 is separated integrally with the peripheral edge portion We. The method of separating the processing wafer W is the same as that in Step P3.

Next, the second separation wafer W2 is transferred to the reversing device 60 by the wafer transfer device 32. In the reversing device 60, the front and back surfaces of the second separation wafer W2 are reversed (Step Q5 in FIG. 17). The method of reversing the second separation wafer W2 is the same as that in Step P4.

Next, the first separation wafer W1 and the second separation wafer W2 are transferred to the processing device 70 by the wafer transfer device 32, respectively. In the processing apparatus 70, as shown in FIG. 18E, the separation surface W1a of the first separation wafer W1 is ground, and the peripheral edge modified layer M2 and the internal surface modified layer M3 remaining on the separation surface W1a are removed. At the same time, as shown in FIG. 18F, the separation surface W2a of the second separation wafer W2 is ground to remove the peripheral modified layer M2 and the internal surface modified layer M3 remaining on the separation surface W2a (FIG. 17). Step Q6). The method of grinding the separation surfaces W1a and W2a is the same as that in Step P5.

Next, the first separation wafer W1 and the second separation wafer W2 are transferred to the cleaning devices 51 and 52 by the wafer transfer device 32, respectively. In the cleaning devices 51 and 52, the separation surfaces W1a and W2a are scrub-cleaned (step Q7 in FIG. 17). The method for cleaning the separation surfaces W1a and W2a is the same as that in Step P6.

Next, the first separation wafer W1 and the second separation wafer W2 are transferred to the

wet etching devices

40 and 41 by the wafer transfer device 22, respectively. In the

wet etching devices

40 and 41, the separation surfaces W1a and W2a are wet-etched, respectively (Step Q8 in FIG. 17). Note that the wet etching method of the separation surfaces W1a and W2a is the same as that in Step P7.

でも In this embodiment, the same effects as in the above embodiment can be enjoyed. Moreover, according to the present embodiment, in performing the edge trimming, after forming the peripheral edge modified layer M2 inside the processing wafer W in step Q2, the peripheral edge We is removed with the peripheral edge modified layer M2 as a base point. I have. For example, in the conventional method, the peripheral edge portion We is ground or cut, and the grinding wheel is worn, so that periodic replacement is required. On the other hand, in this embodiment, the degree of deterioration of the laser head 90 itself with time is small, and the frequency of maintenance can be reduced.

However, the present disclosure does not exclude edge trimming by grinding.

In addition, the formation of the peripheral edge modified layer M2 in step Q1 and the formation of the inner surface modified layer M3 in step Q3 can be performed in the same reforming separation device 61. Therefore, equipment costs can be reduced. The formation of the peripheral edge modified layer M2 and the formation of the internal surface modified layer M3 may be performed by separate apparatuses. For example, in the case where the above-described wafer processing is continuously performed on a plurality of overlapped wafers T, by forming the peripheral edge modified layer M2 and the internal surface modified layer M1 using different apparatuses, the throughput of the wafer processing can be reduced. Can be improved.

In the above-described reforming separation device 61, the laser head 90 forms the peripheral modified layer M2 and the internal surface modified layer M3. However, the peripheral modified layer M2 and the internal surface modified layer M3 are separately formed. May be formed using the laser head described above.

方法 The method of performing the edge trim in the wafer processing system 1 is not limited to the above embodiment. Next, a wafer process according to another embodiment will be described. This embodiment is almost the same as the embodiment shown in FIG. 18, except for the internal surface modification layer formed in step Q3.

In step Q3, an internal surface modification layer M4 is formed inside the processing wafer W as shown in FIG. While the internal surface modified layer M3 shown in FIG. 18 is formed up to the peripheral edge modified layer M2, the internal surface modified layer M4 of the present embodiment extends from the center to the outer end in the surface direction. It is formed. Note that the crack C4 extends from the inner surface modified layer M4 in the surface direction. When the pitch of the internal surface modification layer M4 is small, the crack C4 may not be provided.

In such a case, in step Q4, as shown in FIG. 20D, the second separation wafer W2 above the internal surface modified layer M4 and the peripheral portion We below the internal surface modified layer M4 are separately separated. Separated. That is, the second separation wafer W2 is separated based on the inner surface modified layer M4, and the peripheral portion We is separated based on the peripheral modified layer M2. The other steps Q1 to Q2 and Q5 to B8 are the same as those in the embodiment shown in FIG.

も In the present embodiment, the same effects as in the above embodiment can be enjoyed.

In the above-described embodiment, when performing the edge trimming in the wafer processing system 1, the peripheral portion We is removed when the processing wafer W is separated. However, even if the processing wafer W is separated after removing the peripheral portion We. Good.

In such a case, in the reforming / separating apparatus 61, first, in step Q2, the peripheral reforming layer M5 and the divided reforming layer M6 are formed inside the processing wafer W as shown in FIG.

。 As shown in FIG. 22, the laser head 90 is moved above the processing wafer W to the boundary between the peripheral edge We and the central part Wc of the processing wafer W. Thereafter, the laser beam L is irradiated from the laser head 90 to the inside of the processing wafer W while the chuck 80 is rotated by the rotating unit 82, so that the peripheral edge modified layer M5 is formed inside the processing wafer W.

As in the case of the peripheral modified layer M2 of the above embodiment, the peripheral modified layer M5 extends in the thickness direction, and the lower end of the peripheral modified layer M5 is positioned on the target surface of the ground processing wafer W (the dotted line in FIG. 22). ).

{Circle around (5)} Cracks C5 propagate from the peripheral edge modified layer M5 inside the processed wafer W and reach the front surface Wa and the back surface Wb. Note that a plurality of peripheral edge modified layers M5 may be formed in the thickness direction.

Next, the laser head 90 is moved in the same reforming / separating apparatus 61 to form a divided reformed layer M6 inside the processing wafer W and radially outside the peripheral reformed layer M5. The split modified layer M6 also extends in the thickness direction similarly to the peripheral modified layer M5, and has a vertically long aspect ratio. In addition, the crack C6 extends from the divided modified layer M6 and reaches the front surface Wa and the back surface Wb. Note that a plurality of divided modified layers M6 may also be formed in the thickness direction.

Then, by forming a plurality of divided modified layers M6 and cracks C6 in the radial direction at a pitch of several μm, as shown in FIG. The layer M6 is formed. In the illustrated example, the divided modified layers M6 of the line extending in the radial direction are formed at eight positions, but the number of the divided modified layers M6 is arbitrary. At least the peripheral edge portion We can be removed if the divided modified layer M6 is formed at two places. In such a case, when the peripheral edge portion We is removed in the edge trim, the peripheral edge portion We is divided into a plurality of parts by the divided modified layer M6 while being separated from the annular peripheral modified layer M5 as a base point. Then, the peripheral edge portion We to be removed is fragmented and can be more easily removed.

Next, in the same reforming and separating apparatus 61, the peripheral portion We of the processing wafer W is removed starting from the peripheral modified layer M5 as shown in FIG. A tape 150 shown in FIG. 24 is provided in the reforming separation device 61 of the present embodiment, and the tape 150 is expanded (expanded) to remove the peripheral edge We.

First, as shown in FIG. 24A, the expandable tape 150 is attached to the back surface Wb of the processing wafer W. Subsequently, as shown in FIG. 24B, the tape 150 is expanded in the radial direction of the processing wafer W, and the peripheral portion We is separated from the processing wafer W based on the peripheral edge modified layer M5. Also, at this time, the peripheral edge portion We is divided into small pieces and separated from the division reforming layer M6. Thereafter, as shown in FIG. 24C, the tape 150 is lifted and separated from the processing wafer W, and the peripheral edge portion We is removed. At this time, in order to facilitate the peeling of the tape 150, a process of reducing the adhesive strength of the tape 150, for example, an ultraviolet irradiation process may be performed.

The method of removing the peripheral edge portion We is not limited to the present embodiment. For example, an air blow or a water jet may be jetted to the peripheral portion We, and the peripheral portion We may be removed by pressing. Alternatively, for example, a jig such as tweezers may be brought into contact with the peripheral edge We to physically remove the peripheral edge We.

Next, in the same reforming / separating apparatus 61, the internal surface modified layer M7 is formed in step Q3 as shown in FIG. 21 (d), and further, in step Q4, the processing wafer W is The wafer is separated into separation wafers W1 and W2.

Next, in the reversing device 60, the front and back surfaces of the second separation wafer W2 are reversed in step Q5. Thereafter, in step Q6, the separation surfaces W1a and W2a are ground in the processing device 70 as shown in FIGS. 21 (f) and 21 (g). Thereafter, step Q7 is performed in the cleaning devices 51 and 52, and step Q8 is performed in the

wet etching devices

40 and 41. Thus, a series of wafer processing in the wafer processing system 1 ends.

も In the present embodiment, the same effects as in the above embodiment can be enjoyed. Moreover, according to the present embodiment, since the divided modified layer M6 is formed in step Q2, the peripheral edge portion We to be removed can be reduced into small pieces. Therefore, edge trimming can be performed more easily.

In the

wafer processing systems

1, 200, and 300 of the above embodiments, the bonding of the processing wafer W and the support wafer S is performed by a bonding apparatus outside the

wafer processing systems

1, 200, and 300. It may be provided inside the

processing system

1, 200, 300.

If the oxide films Fw and Fs are also bonded at the peripheral edge portion We when bonding the processing wafer W and the support wafer S, pre-processing is performed on the oxide films Fw and Fs before the bonding process. May go. As the pretreatment, for example, the surface layer of the oxide film Fw at the peripheral edge We may be removed, or the oxide film Fw may be made to protrude. Alternatively, the surface of oxide film Fw may be roughened to be rough. By performing such pretreatment, bonding of the oxide films Fw and Fs at the peripheral portion We can be suppressed. That is, it is possible to form an unbonded region of the oxide films Fw and Fs at the peripheral portion We. Thus, the peripheral edge portion We can be appropriately removed.

Also, in the above example, the unjoined region is formed before the joining process, but the unjoined region may be formed after the joining process. For example, after bonding the processing wafer W and the support wafer S, by irradiating the outer periphery of the oxide film Fw with laser light, the bonding strength can be reduced and an unbonded region can be formed.

In the above embodiments, the case where the processing wafer W and the support wafer S are directly bonded has been described. However, the processing wafer W and the support wafer S may be bonded via an adhesive.

In the above embodiment, the case where the processing wafer W in the overlapped wafer T is thinned has been described, but the above embodiment can also be applied to the case where one wafer is thinned. Further, the above embodiment can be applied to a case where the overlapped wafer T is separated into the processing wafer W and the support wafer S.

実施 The embodiments disclosed this time are to be considered in all respects as illustrative and not restrictive. The above embodiments may be omitted, replaced, or modified in various forms without departing from the scope and spirit of the appended claims.

Reference Signs List 1 wafer processing system 32 wafer transfer device 60 reversing device 61 reforming / separating device 70 processing device S support wafer T superposed wafer W processing wafer

Claims

A substrate processing system for processing a substrate,
A separation unit that separates the substrate into a first separation substrate and a second separation substrate, starting from an internal surface modification layer formed in a plane direction inside the substrate;
A processing unit for grinding the separation surface of the first separation substrate and the separation surface of the second separation substrate, respectively;
At least for the separation unit or the processing unit, a transport mechanism for transporting the substrate,
A reversing mechanism for reversing the front and back surfaces of the second separation substrate.
2. The substrate processing system according to claim 1, wherein the transfer mechanism transfers the first separation substrate and the second separation substrate to at least the separation unit or the processing unit. 3.
The processing unit is
A plurality of holding units for holding the substrate, the first separation substrate or the second separation substrate, and a rotatable rotary table;
A first grinding unit for grinding a separation surface of the first separation substrate held by the holding unit;
The substrate processing system according to claim 1, further comprising: a second grinding unit configured to grind a separation surface of the second separation substrate held by the holding unit.
The substrate processing system according to claim 3, wherein the separation unit is provided above the turntable and separates the substrate held by the holding unit.
The substrate processing system according to claim 4, wherein the separation unit has the reversing mechanism.
The substrate processing system according to any one of claims 1 to 5, wherein the reversing mechanism is provided in the transport mechanism.
The substrate processing system according to any one of claims 1 to 5, further comprising: an internal surface modification unit configured to irradiate the inside of the substrate with a laser beam to form the internal surface modification layer.
8. The semiconductor device according to claim 1, further comprising: a peripheral edge modified portion that forms a peripheral edge modified layer by irradiating a laser beam in a thickness direction along a boundary between a peripheral portion and a central portion to be removed inside the substrate. The substrate processing system according to claim 1.
A substrate processing method for processing a substrate, comprising:
In the separation unit, separating the substrate into a first separation substrate and a second separation substrate, starting from an internal surface modification layer formed in a plane direction inside the substrate;
Reversing the front and back surfaces of the second separation substrate by a reversing mechanism;
A substrate processing method, comprising: grinding a separation surface of the first separation substrate and a separation surface of the second separation substrate in a processing unit.
The processing unit is
A plurality of holding units for holding the substrate, the first separation substrate or the second separation substrate, and a rotatable rotary table;
A first grinding unit for grinding a separation surface of the first separation substrate held by the holding unit;
A second grinding unit for grinding a separation surface of the second separation substrate held by the holding unit,
The grinding of the separation surface of the first separation substrate by the first grinding unit and the grinding of the separation surface of the second separation substrate by the second grinding unit are performed in parallel. Substrate processing method.
The substrate processing method according to claim 10, wherein the separation unit is provided above the turntable and separates the substrate held by the holding unit.
The substrate processing according to any one of claims 9 to 11, wherein the reverse mechanism reverses the front and back surfaces of the second separated substrate while transporting the second separated substrate separated by the separation unit. Method.
The substrate processing method according to any one of claims 9 to 12, wherein before the substrate is separated by the separation unit, the inside of the substrate is irradiated with laser light to form the internal surface modified layer. .
Before separating the substrate at the separation unit, inside the substrate, irradiate a laser beam in the thickness direction along the boundary between the peripheral portion and the central portion of the removal target, to form a peripheral modified layer, The substrate processing method according to any one of claims 9 to 13.