TWI795577B - Substrate processing system and substrate processing method - Google Patents

Abstract

A substrate processing system that processes a substrate has a surface modifying device that modifies an outer peripheral section of a first surface film formed on the surface of a first substrate, before the first surface film is bonded to a second surface film formed on the surface of a second substrate. Furthermore, a substrate processing method that processes a substrate includes a step of modifying an outer peripheral section of a first surface film formed on the surface of a first substrate, before the first surface film is bonded to a second surface film formed on the surface of a second substrate.

Description

Substrate processing system and substrate processing method

The content disclosed in the present invention relates to a substrate processing system and a substrate processing method.

In Patent Document 1, a bonding device for two wafers is disclosed. In the bonding apparatus, first, the center portion of the upper wafer among the two wafers arranged facing each other in the vertical direction is pushed by a push pin, and the center portion is brought into contact with the lower wafer. Then, the spacer supporting the upper wafer is retracted, the entire surface of the upper wafer is brought into contact with the entire surface of the lower wafer, and the wafers are bonded together.

Patent Document 2 discloses an end face grinding device for grinding the peripheral end of a semiconductor wafer. In the end surface grinding device, the disc-shaped grinding tool provided with abrasive grains on the outer periphery is rotated, at least the outer peripheral surface of the grinding tool is in contact with the semiconductor wafer in a linear shape, and the peripheral end of the semiconductor wafer is roughly L-shaped. Grind like. Semiconductor wafers are produced by bonding two silicon wafers together. [Prior art literature] [Patent Document]

Patent Document 1: Japanese Unexamined Patent Publication No. 2004-207436 Patent Document 2: Japanese Patent Application Laid-Open No. 9-216152

[Problem to be solved by the present invention]

The technique disclosed in the present invention suppresses voids generated at the peripheral edge of the substrates when the substrates are bonded together. [Technical means to solve the problem]

One aspect disclosed in the present invention is a substrate processing system for processing a substrate, which is equipped with a surface modifying device, which combines the first surface film formed on the surface of the first substrate with the second surface film formed on the surface of the second substrate. 1 The outer periphery of the surface film is modified. [Effects of the present invention]

According to the disclosure of the present invention, it is possible to suppress the generation of voids at the periphery of the substrates when the substrates are bonded together.

In the three-dimensional integration technology of three-dimensional stacking of semiconductor elements, two semiconductor wafers (hereinafter referred to as wafers) are bonded. Specifically, for example, wafers are bonded by van der Waals force and hydrogen bonding (intermolecular force). The bonding of these wafers is performed, for example, by a bonding device disclosed in Patent Document 1.

In addition, in the manufacturing process of semiconductor devices, the back surface of the bonded superimposed wafers with multiple electronic circuits and other components formed on the surface is ground, and the wafers are thinned. Generally, the peripheral portion of the wafer is chamfered, but when the wafer is subjected to grinding treatment in this way, the peripheral portion of the wafer becomes a sharp shape (so-called edge shape). In this way, there is a possibility that the peripheral portion of the wafer is chipped and the wafer may be damaged. Therefore, so-called edge trimming is performed before the grinding process, and the peripheral portion of the wafer is cut. And this edge trimming, for example, is performed by the end face grinding device disclosed in Patent Document 2.

Here, in order to properly perform wafer bonding, various criteria must be satisfied, and suppression of voids is mentioned as an important criterion among them. In particular, it is difficult to control the porosity (hereinafter referred to as edge porosity) generated at the periphery of the bonded superimposed wafers, and it is necessary to suppress the porosity.

In FIG. 1 , it is illustrated how edge voids are created in superimposed wafers as described above. Here, the wafer W to be processed and the support wafer S are bonded. As will be described later, the element layer D and the oxide film Fw are formed on the surface Wa of the wafer W to be processed, and the oxide film Fs is formed on the surface Sa of the support wafer S. Then, as shown in FIG. 1( a ), the surface Wa of the peripheral portion We of the wafer W to be processed is removed (edge trimming). Afterwards, as shown in FIG. 1( b ), the edge-trimmed processed wafer W is bonded to a support wafer S. At this time, in the bonded superimposed wafer T, the above-mentioned edge void V is formed between the oxide films Fw, Fs. Thereafter, as shown in FIG. 1( c ), in the superimposed wafer T, the back surface Wb of the wafer W to be processed is ground.

If edge voids V are generated in the stacked wafer T, for example, when the back surface Wb of the processed wafer W shown in FIG. peeling off). In addition, cracks, chipping, etc. may occur in the wafer W to be processed based on the peeling. Furthermore, for example, in the stacked wafer T, metal vias or connection pads are formed in the respective wafers W and S, and these vias or connection pads may be connected by diffusion bonding. In this case, if edge voids are formed at the via holes or the connection pads, diffusion bonding may not occur, resulting in poor connection.

In addition, if edge voids V are generated in the overlapped wafer T, the effective area (usable area) of the processed wafer W is also reduced. As shown in FIG. 1 , for example, the distance L1 from the end of the wafer W to be processed before processing to the inner end of the edge hole V is about 7 mm. Therefore, when the diameter of the wafer W to be processed before processing is 300 mm, the effective area becomes an area of φ286 mm.

In this way, if edge voids are generated, the yield of the product will decrease. However, suppression of such edge voids has been a subject until now, including the bonding apparatus disclosed in Patent Document 1.

Thus, the techniques disclosed in the present invention suppress edge voids when bonding wafers to each other. Specifically, the inventors of the present case clarified the mechanism of edge porosity, and based on this insight, thought about a system and method for suppressing edge porosity.

In this embodiment, as shown in FIG. 2 , a wafer W to be processed as a first substrate is bonded to a support wafer S as a second substrate. Hereinafter, in the wafer W to be processed, the surface to be bonded is referred to as a surface Wa, and the surface opposite to the surface Wa is referred to as a rear surface Wb. Similarly, in the support wafer S, the surface to be bonded is called a surface Sa, and the surface opposite to the surface Sa is called a back surface Sb.

The processed wafer W is, for example, a semiconductor wafer such as a silicon wafer, and an element layer D including a plurality of elements is formed on the surface Wa. In addition, on the element layer D, an oxide film Fw such as a SiO ₂ film (TEOS film) is further formed as a first surface film.

The supporting wafer S is a wafer supporting the wafer W to be processed. On the surface Sa of the support wafer S, an oxide film Fs, such as a SiO ₂ film (TEOS film), is formed as a second surface film. In addition, the supporting wafer S functions as a protective material, and protects elements on the surface Wa of the wafer W to be processed. In addition, when forming a plurality of elements supporting the surface Sa of the wafer S, an element layer (not shown) is formed on the surface Sa in the same manner as the wafer W to be processed.

In addition, in the drawings used in the following description, the illustration of the element layer D and the oxide films Fw and Fs may be omitted in order to avoid complicated illustrations.

First, the mechanism of edge porosity is explained. When the wafer W to be processed is bonded to the support wafer S, first, the surfaces of the oxide films Fw and Fs are activated by plasma treatment under a reduced-pressure atmosphere before bonding. After that, the activated surface is hydrophilized, and OH groups (hydroxyl groups) are given to the dangling bonds formed on the surface. Then, when the oxide films Fw and Fs are brought into contact during bonding, the OH groups are hydrogen-bonded, and the oxide films Fw and Fs are joined to each other. In addition, the bonded oxide films Fw and Fs are further annealed to remove water and ensure the bonding strength.

In the bonding apparatus, as shown in FIG. 3( a ), the processed wafer W is sucked and held by the upper chuck 300 , and the support wafer S is sucked and held by the lower chuck 301 . The upper chuck 300 can independently suck the processed wafer W from the suction ports 300 a and 300 b respectively, and the lower chuck 301 can also independently suck the supporting wafer S from the suction ports 301 a and 301 b respectively. Afterwards, as shown in FIG. 3( b ), the suction from the suction port 300 a in the center is stopped, and the pushing member 302 provided on the upper chuck 300 is lowered to push the center of the wafer W to be processed. Then, the central portion of the wafer W to be processed is brought into contact with the central portion of the support wafer S to start bonding by hydrogen bonding, and a so-called bonding wave B is generated. Next, as shown in FIG. 3( c ), the bonding wave B spreads from the center portion to the peripheral portion. When the bonding wave B reaches the peripheral part, as shown in FIG. Then, as shown in FIG. 3( e ), the wafer W to be processed and the support wafer S are bonded.

Here, as shown in FIG. 4 , at the end Be of the bonding wave B, the air in the space between the wafers W and S is compressed to a high pressure. In addition, at the periphery of the wafers W and S, for example, 1 mm to 5 mm from the end, the atmosphere at the end Be of the bonding wave B is compressed to a high pressure (for example, three times the atmospheric pressure), and the atmosphere is released rapidly. decompress to atmospheric pressure. Then, at the peripheral parts of the wafers W and S, the Joule-Thomson effect (Joule-Thomson effect) occurs due to the rapid decompression, and the temperature drops (for example, by 1.5° C.), and condensation occurs. When the wafers W and S are bonded, the dew condensation is sealed at the interface of the oxide films Fw and Fs. Then, when annealing is performed, the water existing at the interface evaporates and expands to form voids. As shown in FIG.

As mentioned above, the inventors of the present application discovered that edge voids are generated by a sudden pressure change between the wafers W and S. Therefore, the inventors of the present invention conceived of suppressing this sudden pressure change and suppressing the edge pores. 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 addition, in this specification and drawings, the same code|symbol is given to the element which has substantially the same function structure, and repeated description is omitted.

First, the configuration of the wafer processing system of the first embodiment will be described. FIG. 6 is a plan view schematically showing the configuration of the wafer processing system 1 . In addition, in the wafer processing system 1 of the first embodiment, edge trimming is performed after bonding.

The wafer processing system 1 has a configuration in which a carry-out station 2 and a processing station 3 are integrally connected. For example, wafer cassettes Cw, Cs, and Ct, which can respectively accommodate a plurality of processed wafers W, a plurality of support wafers S, and a plurality of overlapping wafers T, are carried in and out to the carry-in station 2 between the outside and the outside. The processing station 3 includes various processing devices for performing predetermined processing on the wafer W to be processed, the support wafer S, and the overlapped wafer T.

In the carry-out station 2, a wafer cassette mounting table 10 is installed. In the illustrated example, a plurality of, for example, four cassettes Cw, Cs, and Ct are arbitrarily placed in a row in the Y-axis direction on the cassette mounting table 10 . In addition, the number of cassettes Cw, Cs, and Ct placed on the cassette mounting table 10 can be determined arbitrarily, and is not limited to this embodiment.

In the carry-out station 2 , a wafer transfer area 20 is provided adjacent to the cassette mounting table 10 . In the wafer transfer area 20, a wafer transfer device 22 is provided which can move arbitrarily on a transfer path 21 extending in the Y-axis direction. The wafer transfer device 22 includes, for example, two transfer arms 23 , 23 , and holds and transfers the wafer W to be processed, the support wafer S, and the stacked wafer T. Each transfer arm 23 is configured to be able to move arbitrarily in the horizontal direction, in the vertical direction, around a horizontal axis, and around a vertical axis. In addition, the structure of the conveyance arm 23 may be arbitrary, and is not limited to this embodiment.

In the processing station 3, a wafer transfer area 30 is provided. In the wafer transfer area 30, a wafer transfer device 32 is provided that can move arbitrarily on a transfer path 31 extending in the X-axis direction. The wafer transfer device 32 is configured to transfer the wafer to be processed W and the support wafer W to the transfer device 34 described later, the bonding device 40 , the internal modification device 41 , the surface modification device 42 , the hydrophobization device 43 , and the processing device 50 . Circle S, overlapping wafer T. Furthermore, the wafer transfer device 32 includes, for example, two transfer arms 33 , 33 , and holds and transfers the wafer W to be processed, the support wafer S, and the stacked wafer T. Each transfer arm 33 is configured to be able to move arbitrarily in the horizontal direction, in the vertical direction, around a horizontal axis, and around a vertical axis. In addition, the structure of the conveyance arm 33 may be arbitrary, and is not limited to this embodiment.

A transfer device 34 is provided between the wafer transfer area 20 and the wafer transfer area 30 for transferring the wafer W to be processed, the support wafer S, and the stacked wafer T.

On the positive side of the Y-axis of the wafer transfer area 30 , the bonding device 40 and the internal reforming device 41 are arranged sequentially in the X-axis direction from the side of the carry-out station 2 . On the negative side of the Y-axis of the wafer transfer region 30 , the surface modifying device 42 and the hydrophobizing device 43 are arranged sequentially in the X-axis direction from the side of the carry-out station 2 .

The bonding device 40 bonds the oxide film Fw of the wafer W to be processed and the oxide film Fs of the support wafer S to each other. Before bonding, the oxide film Fw and the oxide film Fs are respectively activated and hydrophilized. Specifically, when activating the oxide film Fw and the oxide film Fs, for example, oxygen or nitrogen gas, which is a process gas, is excited under a reduced-pressure atmosphere to make plasma and ionization. The oxide film Fw and the oxide film Fs are irradiated with these oxygen ions or nitrogen ions, and the oxide film Fw and the oxide film Fs are plasma-treated to activate them. In addition, pure water is supplied to the thus activated oxide film Fw and oxide film Fs, and OH groups are given to dangling bonds between the oxide film Fw and the oxide film Fs to make them hydrophilic. Then, as shown in FIG. 3 , the oxide film Fw and the oxide film Fs are bonded by hydrogen bonds. Further, an annealing treatment is performed on the bonded superimposed wafer T to remove water from the oxide film Fw and the oxide film Fs, thereby securing the bonding strength.

The internal modification device 41 forms an edge modification layer and a division modification layer inside the wafer W to be processed. The internal modifying device 41 irradiates the inside of the wafer W to be processed with laser light from a laser head (not shown) while the overlapping wafer T is held in rotation by a chuck (not shown). The laser head oscillates the high-frequency pulsed laser light oscillated from the laser light oscillator (not shown), that is, the laser light with a wavelength that is transparent to the processed wafer W, such as infrared light. A predetermined position inside the circle W is spotlighted. Thereby, in the inside of the wafer W to be processed, the portion where the laser light is focused is modified. In addition, as will be described later, the edge modified layer is formed along the boundary between the peripheral portion We to be removed and the central portion in the wafer W to be processed. In addition, as will be described later, the split modified layer is formed to extend radially outside the edge modified layer.

In addition, the laser head is further equipped with a spatial light modulator not shown. The spatial light modulator modulates the laser light to output it. Specifically, the spatial light modulator can control the focus position and phase of the laser light, and can adjust the shape and number (number of branches) of the laser light irradiated to the wafer W to be processed.

The surface modifying device 42 modifies the outer peripheral portion of the oxide film Fw of the wafer W to be processed, and removes the outer peripheral portion in this embodiment. In the surface modifying device 42, wet etching is performed on the outer peripheral portion of the oxide film Fw with an etchant such as hydrofluoric acid.

The hydrophobization device 43 immerses the stacked wafer T in an organic solvent, for example, to bind CH ₃ groups (methyl groups) to the surfaces of the unbonded oxide films Fw and Fs. On the interface of the oxide films Fw and Fs bonded by the bonding device 40, as described later, a bonding region where the oxide films Fw and Fs are bonded and an unbonded area corresponding to the oxide film Fw removed by the surface modifying device 42 are formed. area. In the hydrophobizing means 43, for example, CH ₃ groups are bonded to the dangling bonds formed on the surface of the oxide films Fw, Fs in the non-bonded regions, thereby being hydrophobized. In addition, the hydrophobization of the surfaces of the oxide films Fw and Fs is not limited to bonding of CH ₃ groups, for example, other groups including carbon may be bonded to the surfaces of the oxide films Fw and Fs. In addition, in this embodiment, although the stacked wafer T is immersed in an organic solvent, the method of imparting CH ₃ groups is not limited to this form, and the organic solvent may be supplied to the surfaces of the oxide films Fw and Fs. For example, the surfaces of the oxide films Fw and Fs may be exposed to an organic solvent atmosphere.

A processing device 50 is disposed on the positive X-axis side of the wafer transfer area 30 . The processing device 50 performs processing such as grinding or cleaning on the wafer W to be processed.

The processing device 50 includes a rotary table 60 , a transfer unit 70 , an alignment unit 80 , a first cleaning unit 90 , a second cleaning unit 100 , a rough grinding unit 110 , a middle grinding unit 120 , and a finish grinding unit 130 .

The rotating table 60 is configured to be freely rotatable by a rotating mechanism (not shown). Four suction cups 61 are provided on the turntable 60 to suck and hold the overlapped wafer T. The suction pads 61 are equally arranged on the same circumference as the turntable 60 , that is, every 90 degrees. By rotating the turntable 60, the four suction pads 61 can be moved to the transfer position A0 and the processing positions A1 to A3. In addition, the suction pad 61 is held on a suction pad base (not shown), and is configured to be rotatable by a rotation mechanism (not shown).

In this embodiment, the transfer position A0 is on the negative side of the X-axis of the turntable 60 and is on the negative side of the Y-axis. On the negative side of the X-axis of the transfer position A0, the second cleaning unit 100 and the alignment unit 80 are arranged side by side. , and the first cleaning unit 90. The alignment unit 80 and the first cleaning unit 90 are stacked and arranged sequentially from above. The first processing position A1 is a position on the positive side of the X-axis and negative direction of the Y-axis of the turntable 60 , and the rough grinding unit 110 is arranged therein. The second processing position A2 is a position on the positive side of the X-axis and the positive direction of the Y-axis of the turntable 60 , and the middle grinding unit 120 is arranged therein. The third machining position A3 is a position on the negative side of the X-axis and the positive side of the Y-axis of the turntable 60 , and the finish grinding unit 130 is arranged therein.

The transfer unit 70 is an articulated robot and includes a plurality of, for example, three robotic arms 71. The three robotic arms 71 are each configured to be able to rotate freely. On the robot arm 71 at the front end, a transfer pad 72 for sucking and holding the overlapped wafer T is installed. In addition, the robot arm 71 at the base end is attached to the movement mechanism 73 that moves the robot arm 71 in the vertical direction. The transport unit 70 having such a configuration can transport the overlapped wafer T to the transfer position A0 , the alignment unit 80 , the first cleaning unit 90 , and the second cleaning unit 100 .

The alignment unit 80 adjusts the orientation of the horizontal direction of the overlapped wafer T before grinding. For example, the superimposed wafer T held on a chuck (not shown) is rotated, and the position of the notch of the processed wafer W is detected by a detection unit (not shown), so as to adjust the position of the notch and adjust the superposed wafer. The horizontal orientation of T.

The first cleaning unit 90 cleans the back surface Wb of the processed wafer W after the grinding process, more specifically, spin cleans it.

The second cleaning unit 100 cleans the back surface Sb of the support wafer S holding the polished wafer W on the transfer pad 72 , and cleans the transfer pad 72 .

The rough grinding unit 110 rough grinds the backside of the wafer W to be processed. The rough grinding unit 110 includes a rough grinding unit 111 having a ring-shaped rough grinding wheel (not shown) which can be rotated arbitrarily. In addition, the rough grinding part 111 is configured to be movable in the vertical direction and the horizontal direction along the pillar 112 . In the state where the back surface of the wafer W to be processed held on the chuck 61 abuts against the rough grinding wheel, the chuck 61 and the rough grinding wheel are rotated, and the rough grinding wheel is further lowered, whereby the wafer W to be processed is Coarse grinding on the back.

The center grinding unit 120 is used for center grinding the backside of the wafer W to be processed. The middle grinding unit 120 includes a middle grinding part 121 provided with a ring-shaped middle grinding wheel (not shown) which can be rotated arbitrarily. In addition, the middle grinding part 121 is configured to be movable in the vertical direction and the horizontal direction along the pillar 122 . In addition, the grain size of the abrasive grains of the medium grinding wheel is smaller than that of the coarse grinding wheel. In the state where the back surface of the wafer to be processed W held by the chuck 61 abuts against the middle grinding wheel, the chuck 61 and the middle grinding wheel are rotated, and the middle grinding wheel is further lowered, thereby grinding the back side.

The finish grinding unit 130 finishes grinding the backside of the wafer W to be processed. The finish grinding unit 130 includes a finish grinding unit 131 including a ring-shaped finish grinding wheel (not shown) that can be rotated arbitrarily. In addition, the finish grinding part 131 is configured to be movable in the vertical direction and the horizontal direction along the pillar 132 . In addition, the grain size of the abrasive grains of the fine grinding wheel is smaller than that of the medium grinding wheel. While the back surface of the wafer W held by the chuck 61 is in contact with the finish grinding wheel, the chuck 61 and the finish grinding wheel are rotated, and the finish grinding wheel is further lowered to finish grinding the back surface.

In addition, in this embodiment, as will be described later, the peripheral portion We of the wafer W to be processed is removed in the rough polishing unit 110 (or the rough polishing unit 110 and the intermediate polishing unit 120 ), and the processing device 50 constitutes a peripheral edge removing device.

In the wafer processing system 1 described above, a control device 140 is provided. The control device 140 is, for example, a computer, and includes a program storage unit (not shown). Programs for controlling wafer processing in the wafer processing system 1 are stored in the program storage section. In addition, the program storage section also stores programs for controlling the operation of the driving systems of the above-mentioned various processing devices and transfer devices, etc., and realizing the wafer processing described later in the wafer processing system 1 . In addition, the above-mentioned program is recorded on a computer-readable recording medium H, and can also be installed to the control device 140 from the recording medium H.

Next, the surface modifying device 42 will be described. As shown in FIG. 7 , the surface modifying device 42 includes a chuck 150 that holds the wafer W to be processed with the oxide film Fw facing upward. The suction pad 150 is configured to be rotatable around a vertical axis by a rotation mechanism 151 . Above the chuck 150, a nozzle 152 for applying the etchant E to the outer peripheral portion of the oxide film Fw is provided. The nozzle 152 communicates with an etchant supply source (not shown) that stores and supplies the etchant E. In addition, the nozzle 152 is configured to be movable in the X-axis direction, the Y-axis direction, and the Z-axis direction by a moving mechanism (not shown).

The surface modifying device 42 removes the surface layer of the outer peripheral portion Fwe of the oxide film Fw with an etchant E as shown in FIG. 8( a ). Then, as shown in FIG. 8( b ), in the outer peripheral portion Fwe, the oxide films Fw and Fs are not joined during the joining process. That is, when the oxide films Fw and Fs are bonded, a bonding region Ac where the oxide films Fw and Fs are bonded and an unbonded region Ae corresponding to the outer peripheral portion Fwe are formed at the interface of the oxide films Fw and Fs.

Here, as described above with reference to FIG. 4 , the high-pressure ambient atmosphere is formed at the end of the bonding wave, and the ambient atmosphere is opened to the atmosphere and rapidly depressurized to atmospheric pressure, thereby generating edge voids. In this regard, since the unjoined region Ae is formed in this embodiment, the space opened by the high-pressure atmosphere at the end of the joining wave becomes small, and the pressure is not reduced to atmospheric pressure. By suppressing sudden decompression in this way, edge pores can be suppressed.

In addition, the thickness H excluding the outer peripheral portion Fwe shown in FIG. 8 is preferably within 400 nm from the surface. As the thickness H of the outer peripheral portion Fwe becomes larger than 400 nm, the open space of the ambient atmosphere at the end of the bonding wave becomes larger, and the degree of decompression becomes larger. Therefore, it is preferable to make the thickness H of the outer peripheral portion Fwe thin. On the other hand, the inventors of the present application conducted experiments and confirmed that edge voids can be reliably suppressed when the thickness H of the outer peripheral portion Fwe is within 400 nm.

Furthermore, the width La of the unbonded region Ae shown in FIG. 8 is, for example, within 4 mm. In addition, this width La does not promote the generation of edge voids, and even if the width La is as large as 4 mm, the edge voids can still be suppressed. However, as will be described later, in order to increase the effective area of the wafer W to be processed, it is desirable to reduce the width La as much as possible.

Next, wafer processing performed using the wafer processing system 1 configured as described above will be described.

First, the cassette Cw containing a plurality of wafers W to be processed and the cassette Cs containing a plurality of support wafers S are placed on the cassette loading table 10 of the carry-out station 2 .

Next, the wafer W to be processed in the cassette Cw is taken out by the wafer transfer device 22 and transferred to the transfer device 34 . Next, the wafer W to be processed on the transfer device 34 is taken out by the wafer transfer device 32 and transferred to the surface modification device 42 . In the surface modifying device 42, the etchant E is supplied to the outer peripheral portion Fwe of the oxide film Fw of the wafer W to be processed, and as shown in FIG. 10(a), the surface layer of the outer peripheral portion Fwe is removed (step P1 of FIG. 9 ). . At this time, the outer peripheral portion Fwe is removed so that the distance L2 from the end of the wafer W to be processed becomes approximately 0.5 mm.

In addition, in parallel with this step P1, the support wafer S in the wafer cassette Cs is taken out by the wafer handling device 22 and transported to the bonding device 40 by the wafer handling device 32 via the transfer device 34 .

Next, the processed wafer W is transferred to the bonding device 40 by the wafer transfer device 32 . At this time, the front and back of the wafer W to be processed are reversed by the wafer transfer device 22 or an inversion device (not shown). In the bonding device 40 , as shown in FIG. 10( b ), the oxide film Fw of the wafer W to be processed is bonded to the oxide film Fs of the support wafer S to form a superimposed wafer T (step P2 in FIG. 9 ). At this time, a joined region Ac and a non-joined region Ae are formed at the interface of the oxide films Fw, Fs, and the oxide films Fw, Fs are not joined at the outer peripheral portion Fwe. And by this non-bonding region Ae, the space opened by the high-pressure atmosphere at the end of the bonding wave is reduced, and the pressure is not reduced to atmospheric pressure. By suppressing sudden decompression in this way, edge pores can be suppressed.

Next, the superimposed wafer T is transferred to the hydrophobization device 43 by the wafer transfer device 32 . In the hydrophobization device 43, the superimposed wafer T is immersed in an organic solvent, as shown in FIG. 10(c), so that CH ₃ groups are bonded to the surfaces of the oxide films Fw and Fs in the unbonded region Ae (step P3 in FIG. 9 ) . In this way, by hydrophobizing the surface of the oxide films Fw and Fs in the unjoined region Ae, for example, adhesion (bonding) of the oxide films Fw and Fs due to moisture in the atmosphere after the bonding process can be suppressed. Therefore, edge voids can be more reliably suppressed. In addition, if the oxide films Fw and Fs are in close contact, the peripheral portion We of the wafer W to be processed may not be properly removed in step P5 described later. However, by making the surfaces of the oxide films Fw and Fs hydrophobic, This removal of the peripheral portion We can be appropriately performed. In addition, for example, in a dry environment, the oxide films Fw and Fs may not be in close contact after the bonding process due to the humidity of the surrounding environment. In this case, step P3 becomes unnecessary and can be omitted.

Next, the superimposed wafer T is transferred to the internal modification device 41 by the wafer transfer device 32 . In the internal modification device 41, the wafer W to be processed is rotated, and the inside of the wafer W to be processed is irradiated with laser light from a laser head. Then, as shown in FIG. 10(d) and FIG. 11 , along the boundary between the peripheral portion We and the central portion Wc of the wafer W to be processed, an annular edge modified layer M1 is formed inside the wafer W to be processed. (Step P4 of Figure 9). The edge modification layer M1 is preferably formed to coincide with the boundary between the joined region Ac and the unjoined region Ae, or to be radially inward of the boundary. In addition, in the illustrated example, the edge modified layers M1 are formed at seven places in the thickness direction of the wafer W to be processed, but the number of the edge modified layers M1 is arbitrary.

In addition, when the edge modification layer M1 is formed, the spatial light modulator switches the laser light irradiated from the laser head to adjust its shape and quantity. Specifically, first, as shown in FIG. 12( a ), laser light Lr1 is irradiated on the surface Wa side in the thickness direction of the wafer W to be processed to form edge modified layers M1 ( 1 ) to ( 3 ). The number of condensed points of the laser light Lr1 is one (single-focus processing). Next, as shown in FIG. 12( b ), an edge modified layer M1 ( 4 )- (7). The number of focusing points of the laser light Lr2 is, for example, two, that is, the edge modified layers M1 (4), (5), or the edge modified layers M1 (6), (7) are formed simultaneously (multi-focus processing ).

In addition, the number of formations of the edge modified layer M1 generated by the laser beams Lr1 and Lr2 and the number of condensing points of the laser beams Lr1 and Lr2 are arbitrary numbers. However, in the edge modification layers M1(1)-(3) formed on the device layer D side of the wafer W to be processed, the cracks developing in the direction of the device layer D are controlled, that is, the damage to the device layer D is suppressed. Therefore, it is preferable to form the edge modification layer M1 with high precision by this single-focus processing. On the other hand, the possibility of damage to the device layer D by the edge modified layers M1 (4)-(7) is lower than that of the edge modified layers M1 (1)-(3), so by implementing the multi-focus Processing to improve the processing capacity of the internal reforming device 41.

Next, the laser head is moved, and the inside of the wafer W to be processed is irradiated with laser light from the laser head. Then, as shown in FIG. 10( d ) and FIG. 11 , a segmented modified layer M2 extending radially toward the wafer W to be processed is formed on the radially outer side of the edge modified layer M1 (step P4 in FIG. 9 ). In addition, in the illustrated example, the split modified layer M2 is formed at 8 locations in the circumferential direction of the wafer W to be processed and 7 locations in the thickness direction, but the number of split modified layers M2 is arbitrary.

In addition, when forming the split modifying layer M2, the spatial light modulator switches the laser light irradiated from the laser head to adjust its shape and quantity. Specifically, as shown in FIG. 13 , the inside of the wafer W to be processed is irradiated with laser light Lr3 to form the divided modified layer M2 . The number of focusing points of the laser light Lr3 is, for example, two (multi-focus processing).

In addition, the number of divisional modified layers M2 formed by the laser light Lr3 and the number of condensing points of the laser light Lr3 are arbitrary numbers. This split modifying layer M2 is formed at the position to be removed by the subsequent edge trimming. In addition, as mentioned above, the possibility of causing damage to the element layer D is low, so by performing this multi-focus processing, the internal modification can be improved. The processing capacity of the device 41.

Next, the overlapped wafer T is transferred to the processing device 50 by the wafer transfer device 32 . The superimposed wafer T conveyed to the processing apparatus is transferred to the alignment unit 80 . The alignment unit 80 adjusts the orientation of the wafer W to be processed in the horizontal direction.

Next, the overlapping wafer T is transferred from the alignment unit 80 to the transfer position A0 by the transfer unit 70 , and transferred to the chuck 61 at the transfer position A0 . Thereafter, the suction pad 61 is moved to the first processing position A1. Then, the backside Wb of the wafer W to be processed is roughly ground by the rough grinding unit 110 (step P5 in FIG. 9 ).

In the polishing of the rear surface Wb, as shown in FIG. 10(d), within the wafer W to be processed, the cracks C1 and C2 are approximately linear from the edge modified layer M1 and the split modified layer M2 to the thickness direction. Developed to reach the back Wb and the surface Wa. In addition, as the back surface Wb is polished, as shown in FIG. 10( e ), the peripheral portion We of the wafer W to be processed is peeled and removed based on the edge modified layer M1 and the crack C1 . In addition, at this time, the peripheral portion We is divided into pieces based on dividing the modified layer M2 and the crack C2, and the peripheral portion We can be removed more easily. In addition, in the polishing of the back surface Wb, the unjoined region Ae is formed at the interface of the oxide films Fw and Fs, so that the peripheral portion We can be properly removed.

In addition, the distance L2 between the end of the processed wafer W before the processing in step P1 and the end of the processed wafer W after the processing in step P5 may be about 0.5 mm. That is, the effective area becomes an area of φ299 mm. Therefore, compared with the conventional example shown in FIG. 1, the effective area can be enlarged. In this embodiment, edge voids can be suppressed, so that the effective area can be increased. In addition, in step P5, the peripheral portion We can be removed based on the edge modified layer M1, so the width (trimming width) of the peripheral portion We can be reduced, and the effective area can be further increased. For example, if the edge is trimmed using a grinding tool (knife) as known, a trimming width of about 2 mm is required, but this embodiment does not use a grinding tool, so that the trimming width can be reduced.

Next, the suction pad 61 is moved to the second processing position A2. Then, the back surface Wb of the wafer W to be processed is ground by the middle grinding unit 120 . In addition, in the case where the peripheral portion We cannot be completely removed in the above-mentioned rough grinding unit 110 , the peripheral portion We is completely removed by the grinding unit 120 .

Next, the suction pad 61 is moved to the third processing position A3. Then, the backside Wb of the wafer W to be processed is finely ground by the fine grinding unit 130 .

Next, the suction pad 61 is moved to the transfer position A0. Here, the backside Wb of the wafer W to be processed is preliminarily cleaned with a cleaning solution using a cleaning solution nozzle (not shown). At this time, cleaning is performed to remove contamination on the back surface Wb to a certain extent.

Next, the superimposed wafer T is transferred from the transfer position A0 to the second cleaning unit 100 by the transfer unit 70 . Then, in the second cleaning unit 100 , the back surface Sb of the support wafer S is cleaned and dried while the wafer W to be processed is held on the transfer pad 72 .

Next, the superimposed wafer T is transferred from the second cleaning unit 100 to the first cleaning unit 90 by the transfer unit 70 . Then, in the first cleaning unit 90 , the back surface Wb of the wafer W to be processed is finished cleaned with a cleaning solution using a cleaning solution nozzle (not shown). At this time, the back surface Wb is washed and dried to a desired degree of cleanliness.

Afterwards, the overlapped wafer T that has undergone all the processes is transported to the transfer device 34 by the wafer transport device 32 , and further transported to the cassette Ct of the cassette loading table 10 by the wafer transport device 22 . In this way, a series of wafer processing by the wafer processing system 1 ends.

According to the above-mentioned first embodiment, the surface layer of the outer peripheral portion Fwe of the oxide film Fw is removed in step P1, and when the oxide films Fw and Fs are joined in step P2, an unjoined region Ae is formed at the interface of the oxide films Fw and Fs. Such unbonded regions Ae can suppress rapid decompression of the ambient atmosphere at the end of the bonding wave, and as a result, edge voids can be suppressed.

In addition, in step P3, CH ₃ groups are bonded to the surfaces of the oxide films Fw and Fs in the unjoined region Ae to make them hydrophobic, so that the adhesion (joining) of the oxide films Fw and Fs can be suppressed. In this way, since the unjoined area Ae can be ensured, edge voids can be further suppressed. In addition, by hydrophobizing the surfaces of the oxide films Fw and Fs in the unbonded region Ae, the removal of the peripheral portion We of the wafer W to be processed can be appropriately performed in step P5.

Furthermore, in this embodiment, the effective area of the wafer W to be processed can also be increased by suppressing edge voids. In addition, in this embodiment, the peripheral portion We can be removed with the modified layer M as the base point in step P5, so the width (trimming width) of the peripheral portion We can be reduced to further increase the effective area. Specifically, in the conventional case shown in FIG. 1 , the distance L1 from the edge portion of the unprocessed wafer W to the edge void V is about 7 mm, and the effective area is an area of φ286 mm. In contrast, in this embodiment shown in FIG. 9 , the distance L2 between the end of the wafer W to be processed before the process in step P1 and the end of the wafer W to be processed after the process in step P5 is about 0.5 mm, The effective area is an area of φ299mm. In this way, compared with the past, in this embodiment, the effective area of the wafer W to be processed can be increased, and wafers as finished products can be mass-produced.

In addition, in this embodiment, after sequentially performing the activation treatment, hydrophilization treatment, bonding treatment, and annealing treatment of the oxide films Fw and Fs in step P2, the oxide films Fw and Fs of the unbonded region Ae are made in step P3 surface hydrophobization. In this regard, step P3 may be performed between the hydrophilization treatment and the joining treatment of step P2, or may be performed between the joining treatment and the annealing treatment.

In addition, the wafer processing system 1 of this embodiment includes a bonding device 40, an internal modifying device 41, a surface modifying device 42, a hydrophobizing device 43, and a processing device 50, but these devices are configured arbitrarily. For example, the bonding device 40 and the surface modifying device 42 may be installed in one system, and the internal modifying device 41, the hydrophobizing device 43, and the processing device 50 may be installed in another system.

In addition, for example, as shown in FIG. 14 , an internal modification device 41 and a processing device 50 may be installed in the wafer processing system 1, and a bonding device 40, a surface modification device 42, and a hydrophobizing device may be installed in other systems (not shown). device 43.

In this case, as shown in FIG. 14 , the wafer cassette Ct capable of accommodating a plurality of overlapping wafers T is carried in and out to the carry-in station 2 of the wafer processing system 1 . On the cassette mounting table 10, these cassettes Ct are arbitrarily mounted in a row in the Y-axis direction. In addition, in the processing station 3 , a processing device 50 is provided adjacent to the wafer transfer area 20 . The internal reforming device 41 is disposed inside the machining device 50 on the positive side of the Y-axis of the conveying unit 70 and on the negative side of the X-axis of the finish grinding unit 130 .

In this example, the superimposed wafer T that has been subjected to the above-mentioned steps P1 to P3 in the external system is loaded into the loading/unloading station 2 of the wafer processing system 1 . That is, for the superimposed wafer T carried in, the surface layer of the outer peripheral portion Fwe is removed by the surface modification device 42 (step P1), the oxide films Fw and Fs are bonded by the bonding device 40 (step P2), and the hydrophobization device 43 Hydrophobizing the oxide films Fw and Fs (step P3). Then, steps P4 to P5 are performed on the overlapped wafer T in the wafer processing system 1 . That is, after the modified layer M is formed inside the wafer W to be processed by the internal modification device 41 (step P4), the back surface Wb of the wafer W to be processed is ground by the processing device 50 to remove the peripheral portion We (step P4). P5).

Also in this example, the same effect as that of the above-mentioned first embodiment can be obtained. That is, since the unbonded region Ae is formed on the stacked wafer T loaded into the wafer processing system 1 , edge voids can be suppressed. Then, in this state, the removal of the peripheral portion We of the wafer W to be processed can be appropriately performed.

In other words, this example is as follows. A substrate processing system for processing a substrate, comprising: an internal modifying device formed inside the first substrate along the boundary between the peripheral portion and the central portion of the object to be removed, with respect to a superimposed substrate bonded to a first substrate and a second substrate. modified layer, and the first substrate will be removed within 400nm from the surface in the thickness direction of the surface film in the outer peripheral portion of the surface film; remove. A substrate processing method for processing a substrate, comprising the following steps: an internal modification step, for a superimposed substrate where a first substrate and a second substrate are bonded, along the boundary between the peripheral portion and the central portion of the object to be removed, between the first substrate A modified layer is formed inside, and the first substrate is removed within 400 nm from the surface in the thickness direction of the surface film in the outer peripheral portion of the surface film; and the edge removal step is based on the modified layer, the The periphery is removed.

A substrate processing system for processing a substrate, comprising a surface modifying device for modifying the outer periphery of a first surface film formed on a surface of a first substrate before being bonded to a second surface film formed on the surface of a second substrate Upgrading.

In addition, for example, at least the bonding device 40 may be provided in the wafer processing system 1 , and the internal modifying device 41 , the surface modifying device 42 , and the hydrophobizing device 43 may be provided in other systems.

In this case, in the wafer processing system 1, the surface modification treatment of the wafer W to be processed is performed in another system, that is, the wafer W to be processed from which the surface layer of the outer peripheral portion Fwe is removed is loaded into the wafer processing system. 1. Afterwards, the overlapping wafer T is formed in the bonding device 40 .

In other words, this example is as follows. A substrate processing method for processing a substrate, comprising the following steps: A first substrate preparation step of preparing a first substrate in which the outer periphery of the first surface film is modified by the surface modification step; and In the bonding step, the first surface film of the first substrate prepared in the first substrate preparation step is bonded to the second surface film formed on the surface of the second substrate.

Next, the configuration of the wafer processing system according to the second embodiment will be described. FIG. 15 is a plan view schematically showing the configuration of the wafer processing system 200 . In addition, the wafer processing system 200 of the second embodiment performs edge trimming before bonding.

The wafer processing system 200 has a configuration in which the wafer processing system 1 according to the first embodiment is provided with a peripheral edge removing device 210 instead of the internal modifying device 41 and a hydrophilizing device 220 instead of the hydrophobizing device 43 .

The peripheral edge removing device 210 removes (edge trims) the peripheral edge portion We of the wafer W to be processed, for example, using a grinding tool (not shown) such as a cutter. At this time, the peripheral edge We can be completely removed from the front Wa to the back Wb, but in this embodiment, since the back Wb is ground in a later step, only the surface layer is removed from the front Wa.

The hydrophilization device 220 immerses the stacked wafer T in pure water to bind, for example, OH groups to the surfaces of the oxide films Fw and Fs of the unbonded region Ae. Specifically, OH groups are bonded to dangling bonds formed on the surfaces of the oxide films Fw and Fs in the unjoined region Ae to make them hydrophilic. In addition, in this embodiment, although the stacked wafer T is immersed in pure water, the method of imparting OH groups is not limited to this form, and water vapor may be supplied to the surfaces of the oxide films Fw and Fs. For example, the surfaces of the oxide films Fw and Fs may be exposed to a high-humidity ambient atmosphere.

Next, wafer processing performed using the wafer processing system 200 configured as described above will be described. In addition, in this embodiment, the detailed description of the same processing as that of the first embodiment will be omitted.

First, the wafer W to be processed in the cassette Cw is taken out by the wafer transfer device 22 and transferred to the transfer device 34 . Next, the wafer W to be processed on the transfer device 34 is taken out by the wafer transfer device 32 and transferred to the edge removal device 210 . In the peripheral edge removing device 210 , as shown in FIG. 17( a ), the surface layer of the peripheral portion We of the wafer W to be processed is removed (step Q1 in FIG. 16 ). At this time, the width L3 (trimming width) of the peripheral edge part We was about 2 mm. In addition, as the surface layer of the peripheral portion We is removed, the element layer D and the oxide film Fw of the peripheral portion We are also removed together.

Next, the processed wafer W is transported to the surface modification device 42 by the wafer transport device 32 . In the surface modifying device 42, the etchant E is supplied to the outer peripheral portion Fwe of the oxide film Fw of the wafer W to be processed, and as shown in FIG. 17(b), the surface layer of the outer peripheral portion Fwe is removed (step Q2 in FIG. 16 ). . At this time, the outer peripheral portion Fwe is removed from the inner end portion of the peripheral portion We toward the inner side, and the width of the outer peripheral portion Fwe is about 0.5 mm.

In addition, in parallel with the steps Q1 and Q2, the wafer handling device 22 takes out the support wafer S in the cassette Cs, and transports it to the bonding device 40 by the wafer handling device 32 via the transfer device 34 .

Next, the processed wafer W is transferred to the bonding device 40 by the wafer transfer device 32 . In the bonding device 40 , as shown in FIG. 17( c ), the oxide film Fw of the wafer W to be processed is bonded to the oxide film Fs of the support wafer S to form a superimposed wafer T (step Q3 in FIG. 16 ). At this time, the oxide films Fw, Fs are not joined at the outer peripheral portion Fwe, and a joined region Ac and a non-joined region Ae are formed at the interface of the oxide films Fw, Fs. With these unbonded regions Ae, the space opened by the high-pressure ambient atmosphere at the end of the bonding wave becomes smaller, and the pressure is not reduced to atmospheric pressure. By suppressing sudden decompression in this way, edge pores can be suppressed.

Next, the processed wafer W is transferred to the hydrophilization device 220 by the wafer transfer device 32 . The hydrophilization device 220 immerses the overlapping wafer T in pure water, as shown in FIG. 17( d ), bonds OH groups to the surfaces of the oxide films Fw and Fs in the unbonded region Ae (step Q4 in FIG. 16 ). In this way, by hydrophilizing the surfaces of the oxide films Fw and Fs in the unjoined region Ae, the oxide films Fw and Fs are hydrogen-bonded and brought into close contact. On the other hand, the oxide films Fw and Fs are bonded on the entire surface. At this time, annealing treatment may be further performed. In addition, for example, after bonding the oxide films Fw and Fs in step Q3, the oxide films Fw and Fs in the unbonded region Ae are naturally bonded, for example, by water vapor in the atmosphere, step Q4 is unnecessary and can be omitted.

Next, the overlapped wafer T is transferred to the processing device 50 by the wafer transfer device 32 . The processing device 50 performs the same processing as that of the first embodiment. Then, as shown in FIG. 17( e ), the back surface Wb of the wafer W to be processed is ground (step Q5 in FIG. 16 ).

Afterwards, the overlapped wafer T that has undergone all the processes is transported to the transfer device 34 by the wafer transport device 32 , and further transported to the cassette Ct of the cassette loading table 10 by the wafer transport device 22 . In this way, a series of wafer processing by the wafer processing system 1 ends.

Also in the above-mentioned second embodiment, the same effect as that of the above-mentioned first embodiment can be obtained. That is, when the surface layer of the outer peripheral portion Fwe of the oxide film Fw is removed in step Q2, and when the oxide films Fw and Fs are joined in step Q3, an unjoined region Ae is formed at the interface of the oxide films Fw and Fs. Such unbonded regions Ae can suppress rapid decompression of the ambient atmosphere at the end of the bonding wave, and as a result, edge voids can be suppressed.

In addition, in step Q4, OH groups are bonded to the surfaces of the oxide films Fw and Fs in the unjoined region Ae to make them hydrophilic, so that the oxide films Fw and Fs can be adhered (joined). Furthermore, since the oxide films Fw and Fs can be bonded on the entire surface, the effective area of the wafer W to be processed can be increased.

Furthermore, in this embodiment, by suppressing edge voids and also bringing the oxide films Fw and Fs of the unbonded region Ae into close contact, the effective area of the wafer W to be processed can be increased. Specifically, in the conventional case shown in FIG. 1 , the distance L1 from the end of the unprocessed wafer W to the edge void V is about 7 mm, and the effective area is an area of φ286 mm. On the other hand, in this embodiment shown in FIG. 17, the distance L3 between the end of the wafer W to be processed before the process in step Q1 and the end of the wafer W to be processed after the process in step Q5 is about 2 mm, which is effective. The region becomes a region of φ296mm. In this way, compared with the past, in this embodiment, the effective area of the wafer W to be processed can be increased, and wafers as finished products can be mass-produced.

In addition, in this embodiment, after sequentially performing the activation treatment, hydrophilization treatment, bonding treatment, and annealing treatment of the oxide films Fw and Fs in step Q3, the oxide films Fw and Fs of the unbonded region Ae are made in step Q4 Surface hydrophilization. In this regard, step Q4 may be performed between the hydrophilization treatment and the joining treatment of step Q3, or may be performed between the joining treatment and the annealing treatment. In this case, the annealing treatment in step Q4 can be omitted.

In addition, the wafer processing system 1 of this embodiment includes a bonding device 40, a surface modifying device 42, a processing device 50, a peripheral edge removing device 210, and a hydrophilizing device 220, but these devices may be configured arbitrarily. For example, the bonding device 40 , the surface modifying device 42 , the peripheral edge removing device 210 , and the hydrophilization device 220 may be installed in one system, and the processing device 50 may be installed in another system.

In the first and second embodiments described above, the surface modifying device 42 performs wet etching to remove the outer peripheral portion Fwe of the oxide film Fw, but the method for removing the outer peripheral portion Fwe is not limited to this embodiment. For example, as shown in FIG. 18 , the surface modifying device 230 includes a chuck 231 that holds the wafer W to be processed with the oxide film Fw facing upward. The suction pad 231 is configured to be rotatable around a vertical axis by a rotation mechanism 232 . A polishing member 233 is provided above the chuck 231 for pressing the outer peripheral portion Fwe to remove the oxide film Fw. The polishing member 233 is configured to be movable in the Z-axis direction by a moving mechanism (not shown).

In this way, by removing the peripheral portion Fwe using the polishing member 233, a damaged layer is formed on the surface of the oxide film Fw, so that generation of edge voids V can be suppressed, and re-adhesion of the unbonded region Ae can be properly suppressed.

In addition, the surface grain size of the polishing member 233 can be arbitrarily selected, that is, the abrasive grain size of the polishing member 233 can be arbitrarily selected, so the film removal rate of the oxide film Fw and the surface roughness of the oxide film Fw after film removal can be adjusted arbitrarily. Thereby, generation|occurrence|production of the edge void V and re-adhesion of the unbonded area|region Ae can be suppressed more suitably.

In addition, when removing the oxide film Fw, for example, by using a polishing member 233 having a larger abrasive grain size than the thickness of the oxide film Fw, as shown in FIG. The outer peripheral portion Fwe is removed so that the radially outer side of the oxide film Fw is inclined radially outward, that is, the thickness of the oxide film Fw becomes thinner radially outerward in a side view.

Thus, when the outer peripheral portion Fwe is inclined, as shown in FIG. 19( b ), an unjoined region Ae is formed so that the space gradually expands toward the outer peripheral direction at the interface of the oxide films Fw and Fs. Thereby, during bonding, the high-pressure ambient atmosphere at the end of the bonding wave is gradually reduced to atmospheric pressure toward the outer peripheral direction, that is, rapid pressure reduction can be suppressed, so edge voids V can be appropriately suppressed.

In this way, in the surface modifying device, it is preferable to remove the surface of the outer peripheral portion Fwe so as to be inclined toward the radially outer side of the wafer W to be processed. In the above description, the inclination is formed by the difference between the abrasive particle size of the polishing member 233 and the thickness of the oxide film Fw, but it is also possible to press a polishing member having a shape in which the inclination can be formed in advance, for example, by thinking of polishing The pressing direction of the member 233 is inclined. In addition, the formation of such an inclination of the outer peripheral portion Fwe can also be performed in the case of removing the outer peripheral portion Fwe of the oxide film Fw by wet etching in the surface modifying device 42 . In this case, for example, by controlling the supply angle of the etching liquid or controlling the supply amount of the etching liquid, an inclination is formed toward the outer peripheral direction.

In addition, as described above, when the outer peripheral portion Fwe of the oxide film Fw is removed by the polishing member 233 , removal debris of the oxide film Fw (hereinafter referred to as “swarf”) is generated. Such debris may cause poor bonding between wafers or defective components of products, so it is necessary to prevent them from adhering to the surface of the wafer W to be processed, especially the surface of the component layer D.

Therefore, in order to prevent the debris from adhering to the wafer W to be processed, it is preferable to use a polishing member 233 to perform a surface modification device 230 for removing the oxide film Fw, as shown in FIG. 20( a ). Fluid nozzle 244 for debris dispersion. The fluid nozzle 244 is, for example, disposed above the peripheral portion We of the wafer W to be processed. In addition, for example, pure water or air may be supplied from the fluid nozzle 244 to diffuse debris generated on the polishing surface outward in the outer peripheral direction. Thereby, debris generated by polishing can be prevented from flying radially inward of the wafer W to be processed and adhering to the surface of the wafer W to be processed. In addition, the fluid nozzle 244 may be further provided, for example, above the central portion of the wafer W to be processed or on the back side of the wafer W to be processed in order to scatter the generated debris more reliably outward in the peripheral direction.

In addition, the configuration of the surface modifying device 230 is not limited to the configuration described above, as long as it can scatter generated debris in the outer peripheral direction. For example, as shown in FIG. 20(b), the pressure inside the surface modifying device 230 can be controlled so that the radially inner side of the wafer W to be processed becomes a positive pressure ("+" in FIG. 20(b)), and the outer side It becomes a negative pressure ("-" in Fig. 20(b)). Thereby, an airflow from the radially inner side toward the outer side of the wafer W to be processed is formed in the surface modifying device 230 , and the generated debris can be properly scattered toward the outer peripheral direction. In addition, in this case, by providing a suction mechanism 245 such as a vacuum pump on the outer peripheral direction outer side of the polishing outer peripheral portion Fwe, the air flow from the radially inner side toward the outer side can be more properly formed.

In addition, as in the case of removing the outer peripheral portion Fwe of the oxide film Fw by using the polishing member 233 having a large abrasive grain size as described above, it may not be possible to properly remove the modified layer M (step P4 in FIG. 9 ) to be performed later. The trimming processing position and the alignment with the boundary of the peripheral portion We and the central portion Wc are performed accurately. This is because, for example, as shown in FIG. 21( a), due to the polishing member 233 having a large abrasive grain size, the boundary between the peripheral portion We and the central portion Wc, that is, the inner peripheral side of the peripheral portion We to be removed The edge of the end portion (hereafter sometimes simply referred to as "edge") becomes rough, and it becomes impossible to properly set the trimming position in the radial direction.

On the other hand, the inventors of the present application found that the outer peripheral portion Fwe of the oxide film Fw was removed using a polishing member 234 having a small abrasive grain size, as shown in FIG. 21( b ), and found that The processing accuracy is improved, and the trimming processing position can be set appropriately in the radial direction.

Therefore, when removing the outer peripheral portion Fwe of the oxide film Fw by polishing, as shown in FIG. Area 234a. In the first polishing region 234a, polishing is performed by the polishing member 234 having a small abrasive grain size, so that the processing accuracy of the inner peripheral end of the first polishing region 234a, that is, the edge of the peripheral portion We is improved. Then, following this step, the polishing region produced by the polishing member 234 is left on the edge of the peripheral portion We, that is, the distance L is separated from the inner peripheral end of the first polishing region 234a to both sides in the radial direction. The position is polished to the edge of the wafer W to be processed by the polishing member 233 having a large abrasive grain size to form a second polishing region 233a.

In addition, in the first polished region 234a and the second polished region 233a, in order to properly form the non-joined region Ae and to suppress re-adhesion of the non-joined region Ae, it is preferable to roughen the surface of the oxide film Fw. The area of the second polishing region 233a is large. That is, the first polishing region 234a is only required to ensure the desired processing accuracy of the edge of the peripheral portion We in the alignment process, and the distance L is preferably short. Specifically, by setting the distance L to be at least larger than the diameter of the abrasive grains of the polishing member 233 forming the second polishing region 233a, the alignment process can be properly performed.

Thereby, by improving the processing accuracy of the edge of the peripheral portion We, in addition to properly performing the alignment of the formation of the modified layer M (step P4 in FIG. 9 ), the edge of the wafer W to be processed can also be The formation of a damaged layer on the surface of the oxide film Fw can suppress the generation of edge voids V, and at the same time properly suppress the re-adhesion of the unbonded region Ae. In addition, the abrasive grain size of the polishing member 233 can be arbitrarily selected, so the film removal rate of the oxide film Fw and the surface roughness of the oxide film Fw after film removal can be adjusted arbitrarily. Thereby, generation|occurrence|production of the edge void V and re-adhesion of the unbonded area|region Ae can be suppressed more suitably.

In addition, in the example shown in FIG. 22, the second polishing region 233a is formed after the first polishing region 234a is formed, but the processing order of the polishing members 233 and 234 is not limited to this form. For example, the first polished region 234a may be formed after the second polished region 233a is formed.

In addition, the grinding of the edge of the peripheral portion We by the polishing member 234 having a small abrasive grain size may be performed, for example, when it is inclined toward the radially outer side of the wafer W to be processed as shown in FIG. 19 .

In the first and second embodiments described above, the surface modifying device 42 performs wet etching to remove the outer peripheral portion Fwe of the oxide film Fw, but the method for removing the outer peripheral portion Fwe is not limited to this embodiment. For example, the peripheral portion Fwe may be removed by irradiating the peripheral portion Fwe with laser light having a wavelength that does not transmit the oxide film Fw, such as ultraviolet rays.

In addition, the surface modifying device 42 removes the outer peripheral portion Fwe as the modification treatment of the outer peripheral portion Fwe of the oxide film Fw, but may also make the outer peripheral portion Fwe protrude. In this case, as shown in FIG. 23 , the surface modifying device 240 includes a chuck 241 that holds the wafer W to be processed with the oxide film Fw facing upward. The suction pad 241 is configured to be rotatable around a vertical axis by a rotation mechanism 242 . A laser head 243 is provided above the chuck 241 to irradiate laser light R to the peripheral portion Fwe. Laser light R, for example, uses ultraviolet rays. In addition, the laser head 243 is configured to be movable in the X-axis direction, the Y-axis direction, and the Z-axis direction by a moving mechanism (not shown).

In the surface modifying device 240 , as shown in FIG. 24( a ), the outer peripheral portion Fwe is raised by the laser light R. As shown in FIG. Then, as shown in FIG. 24( b ), the oxide films Fw and Fs are not joined at the outer peripheral portion Fwe. That is, when the oxide films Fw and Fs are bonded, a bonding region Ac where the oxide films Fw and Fs are bonded and an unbonded region Ae corresponding to the outer peripheral portion Fwe are formed at the interface of the oxide films Fw and Fs.

In this case, as in the case where the outer peripheral portion Fwe is removed as shown in FIG. 8 , since the unbonded region Ae is formed in this embodiment, the space opened by the high-pressure atmosphere at the end of the bonding wave becomes smaller, and there is no Reduced pressure to atmospheric pressure. By suppressing sudden decompression in this way, edge pores can be suppressed. Furthermore, by discontinuously forming the protrusions of the outer peripheral portion Fwe in the circumferential direction, the high-pressure ambient atmosphere at the end of the bonding wave can escape to the outside of the superposed wafer T. In this way, even if dew is condensed on the outer peripheral portion Fwe, the water vapor can escape to the outside of the superposed wafer T.

In addition, the surface modifying device 240 uses the laser light R to protrude the outer peripheral portion Fwe, and the laser light R destroys the top of the outer peripheral portion Fwe to roughen the outer peripheral portion Fwe. In this case, the joining of the oxide films Fw and Fs in the outer peripheral portion Fwe can be further suppressed, that is, the unjoined region Ae can be formed more reliably. As a result, rapid decompression is suppressed, and edge porosity can be suppressed.

In addition, the roughening of the Fwe at the peripheral portion can also be performed when the surface layer of the Fwe at the peripheral portion is removed by the surface modifying device 42 .

In addition, the removal of Fwe at the outer peripheral portion by the surface modifying device 240, that is, the removal of Fwe at the outer peripheral portion by laser light R is also related to the removal of Fwe at the outer peripheral portion by the polishing member 233 of the surface modifying device 230. Removal also produces debris.

Debris generated by the irradiation of the laser light R tends to spread easily toward the open space near the point where the laser light R is irradiated. That is, for example, when the oxide film Fw near the center of the wafer W to be processed is irradiated with the laser light R, debris spreads in the circumferential direction centering on the irradiation point of the laser light R. On the other hand, for example, when the oxide film Fw near the outer edge of the wafer W to be processed is irradiated with laser light R, debris tends to spread outward in the open space, that is, the outer peripheral direction of the wafer W to be processed.

In view of the above tendency, the removal of the oxide film Fw by the laser light R can also divide the outer peripheral portion Fwe into a plurality of regions in the radial direction of the wafer W to be processed, and perform sequentially from the radially outer side toward the inner side of the plurality of regions. FIG. 25 shows the area distribution when the outer peripheral portion Fwe of the oxide film Fw is divided, for example, into two ring-shaped areas in the radial direction. As shown in FIG. 25 , the outer peripheral portion Fwe is sequentially divided into annular regions Fwe1 and Fwe2 from the radially outer side.

When removing the outer peripheral portion Fwe by the laser light R, first, the laser light R is irradiated to the irradiation point Pt(1) of the laser light on the annular region Fwe1, and the oxide film Fw of the irradiation point Pt(1) is removed. At this time, the ring-shaped region Fwe1 where the irradiation point Pt(1) is located faces the open space outside the outer peripheral direction of the wafer W to be processed, as shown in FIG. .

The oxide film Fw is removed at the irradiation point Pt( 1 ), and then the wafer W to be processed is rotated to irradiate the irradiation point Pt( 2 ) with laser light R. The irradiation point Pt(2) is set adjacent to the irradiation point Pt(1). At this time, the irradiation point Pt(2) is located in the ring-shaped area Fwe1, and also faces the irradiation point Pt(1) from which the oxide film Fw has been removed, so that debris can be more reliably prevented from moving radially inward of the wafer W to be processed. diffusion. By repeating the series of irradiation operations of the laser light R and the rotation operations of the wafer W to be processed, the oxide film Fw is removed covering the entire circumference of the annular region Fwe1.

After the removal of the oxide film Fw in the annular region Fwe1 is completed, the laser head 243 is moved above the annular region Fwe2 to start the removal of the oxide film Fw in the annular region Fwe2. At this time, the removal of the oxide film Fw in the ring-shaped region Fwe1 has been completed. Therefore, as shown in FIG. Open space diffuses. Then, in the ring-shaped area Fwe2, the aforementioned series of irradiating the laser light R and rotating the wafer W to be processed are repeated to remove the oxide film Fw covering the entire circumference of the ring-shaped area Fwe2.

According to the above operation, the irradiation point of the laser light R always faces the open space outside the outer peripheral direction of the wafer W to be processed, so that the diffusion of debris to the radially inner side of the wafer W to be processed can be suppressed, and it can be appropriately suppressed. Its attachment to the wafer W being processed. In addition, according to the above operation, the scattering direction of the debris can be directed to the outer peripheral direction of the wafer W to be processed, and to the direction of the irradiation point of the previous laser light R, so that the scattering of the debris to the wafer W to be processed can be more appropriately suppressed. It can also simplify the configuration of the exhaust equipment of the surface modifying device 240.

In addition, in order to more properly prevent debris generated by irradiation of laser light from adhering to the wafer W to be processed, the surface modifying device 240 may be provided with, for example, a fluid nozzle in the same manner as the surface modifying device 230 . In addition, of course, the internal pressure of the surface modifying device 240 may be controlled to generate an air flow from the radially inner side to the outer side of the wafer W to be processed, and a suction mechanism may also be provided.

In addition, further, it is also possible to control the depth of the irradiation point of the laser light in the ring-shaped area Fwe2 to be shallower than the depth of the irradiation point of the laser light in the ring-shaped area Fwe1. That is, as shown in FIG. 27 , the depth of the irradiation spot of the laser light R may be changed so that the removed thickness of the oxide film Fw gradually increases toward the radially outer side of the wafer W to be processed. This removes the surface of the outer peripheral portion Fwe with a slight inclination, so that the same effect as the above-mentioned inclined outer peripheral portion Fwe can be obtained, and the occurrence of edge voids V and re-adhesion of the unjoined region Ae can be appropriately suppressed. In addition, at this time, the difference H2 of the removed thickness of each annular region is preferably within 400 nm.

In addition, in the above description, the case where the outer peripheral portion Fwe is divided into two in the radial direction is taken as an example for description, but the number of divisions of the outer peripheral portion Fwe is not limited to this form, and the oxide film Fw can be formed by any number of divisions. surface removal. In this case, by increasing the number of divisions, the resolution of the slight inclination can be increased, and the effect of suppressing the generation of edge voids V and the re-adhesion of the unjoined region Ae can be more appropriately obtained.

Although the above-mentioned embodiment has described the case where the oxide films Fw and Fs are formed on the surface Wa of the wafer W to be processed and the surface Sa of the support wafer S, respectively, it is not limited to the surface films. For example, a SiC film, a SiCN film, or the like may be formed. In addition, the above-mentioned second embodiment can also be applied to the case where the peripheral portion We of the wafer W to be processed is left without being removed, that is, the case where step Q1 is not performed.

In addition, in the above-mentioned embodiment, the unjoined region Ae is formed by removing the oxide film Fw of the outer peripheral portion Fwe, but the method of forming the unjoined region Ae is not limited to this form.

As mentioned above, the oxide film Fw of the wafer W to be processed and the oxide film Fs of the support wafer S are hydrophilized by giving OH groups to the dangling bonds formed on the surfaces of the oxide films Fw and Fs, and the oxide film Fw and the oxide film Fw are hydrophilized. Membrane Fs are joined by hydrogen bonds.

Therefore, in the surface modifying device 330 included in the wafer processing system according to the third embodiment, the unbonded region Ae is formed by supplying a hydrophobizing material to the oxide film Fw of the wafer W to be processed before bonding. Specifically, in the surface modifying device 330 , by supplying the silanization material G to the outer peripheral portion Fwe of the oxide film Fw, hydrophobicization and water repellency of the outer peripheral portion Fwe are performed.

Hereinafter, a surface modifying device 330 according to a third embodiment will be described with reference to the drawings. FIG. 28 is a schematic side view showing the configuration of the surface modifying device 330 . Fig. 29 is a flow chart showing main steps of wafer processing in the wafer processing system according to the third embodiment. In addition, FIG. 30 is an explanatory view showing the state of wafer processing in the third embodiment. In addition, in this embodiment, among elements having substantially the same functional configuration as those in the above-mentioned first and second embodiments, overlapping descriptions are omitted by assigning the same reference numerals.

As shown in FIG. 28 , the surface modifying device 330 includes a chuck 350 that holds the wafer W to be processed with the oxide film Fw facing upward. The suction pad 350 is configured to be rotatable around a vertical axis by a rotation mechanism 351 . A nozzle 352 is provided above the chuck 350 to apply the silanization material G to the outer peripheral portion of the oxide film Fw. The nozzle 352 communicates with a silane material supply source (not shown) that stores and supplies the silane material G. In addition, the nozzle 352 is configured to be movable in the X-axis direction, the Y-axis direction, and the Z-axis direction by a moving mechanism (not shown).

In the wafer processing system of the third embodiment, first, the wafer W to be processed in the cassette Cw is taken out by the wafer transfer device 22 and transferred to the transfer device 34 . Next, the processed wafer W on the transfer device 34 is taken out by the wafer transfer device 32 and transferred to the surface modifying device 330 . In the surface modifying device 330, before performing bonding (before step U2 in FIG. 29), silyl groups (Si—R) are given to the dangling bonds formed on the outer periphery of the oxide film Fw by the silanization material G (Fig. Step U1 of 29). Thereby, as shown in FIG. 30( a ), a silylated region Fws is formed in the outer peripheral portion Fwe.

The wafer W to be processed, in which the silylation region Fws is formed on the outer periphery Fwe, is then transferred to the bonding device 40 by the wafer transfer device 32 . In the bonding device 40, the oxide film Fw is activated and hydrophilized before bonding. In addition, a silyl group is given to the peripheral part Fwe in step U1. Thus, in the hydrophilization treatment of the bonding device 40 , the hydrophilization of the outer peripheral portion Fwe is not performed. Specifically, the hydrophilization treatment is performed by giving OH groups to dangling bonds formed on the oxide film Fw as described above. Here, a silyl group has already been given to the peripheral Fwe to make it hydrophobized and water-repellent, and thus the donation of OH groups to the peripheral Fwe is hindered.

The oxide film Fw is activated and hydrophilized, and then, as shown in FIG. 30(b), the oxide film Fw of the wafer W to be processed is bonded to the oxide film Fs of the support wafer S that has been activated and hydrophilized in advance. , forming a superimposed wafer T (step U2 in FIG. 29 ). At this time, the oxide films Fw, Fs are not joined at the outer peripheral portion Fwe, but a joined region Ac and a non-joined region Ae are formed at the interface of the oxide films Fw, Fs.

Next, the superimposed wafer T is transferred to the internal modification device 41 by the wafer transfer device 32 . In the internal modification device 41, the wafer W to be processed is rotated, and the inside of the wafer W to be processed is irradiated with laser light from a laser head. Then, as shown in FIG. 30(c), along the boundary between the peripheral portion We and the central portion Wc of the wafer W to be processed, an annular edge modification layer M1 is formed inside the wafer W to be processed (FIG. 29 step U3). In addition, further, the laser head is moved to form a segmented modified layer M2 radially extending toward the wafer W to be processed on the radially outer side of the edge modified layer M1.

Next, the overlapped wafer T is transported to the processing device 50 by the transport unit 70 through the alignment unit 80 . Then, the back surface Wb of the wafer W to be processed is ground by the processing apparatus 50, and the peripheral portion We is removed as shown in FIG. 30( d ) (step U4 in FIG. 29 ).

Afterwards, the overlapped wafer T that has undergone all the processes is transported to the transfer device 34 by the wafer transport device 32 , and further transported to the cassette Ct of the cassette loading table 10 by the wafer transport device 22 . In this way, a series of wafer processing by the wafer processing system 1 ends.

According to a series of wafer processes in this embodiment, unlike the first and second embodiments, the oxide film Fw is not removed or the surface is roughened in the unbonded region Ae. That is, the high-pressure atmosphere at the end of the bonding wave B in this embodiment is released at the end of the wafer W to be processed, and edge voids V are generated as shown in FIG. 30( b ). However, since the oxide film Fw is not removed or the surface is roughened as described above, the position where the edge void V occurs is formed on the edge side of the wafer W to be processed, that is, in the peripheral portion We to be removed. Peripheral Fwe. Thereby, even if edge voids are generated, the outer peripheral portion Fwe is not a part where an element is formed, and thus does not substantially affect the manufacturing process of the semiconductor element.

In addition, the silylation of the outer peripheral portion Fwe of the oxide film Fw may be performed at any point of time as long as it is before the bonding of the wafer W to be processed. That is, in the above-mentioned embodiment example, although the silanization treatment was performed before the bonding and before the activation of the oxide film Fw, for example, it may be performed between the activation treatment and the hydrophilization treatment, or after the hydrophilization. Execute after treatment. In either case, the unbonded region Ae can be appropriately formed by performing silylation of the outer peripheral portion Fwe before the hydrogen bonding of the oxide film Fw and the oxide film Fs in the bonding step.

In addition, according to the above-mentioned embodiment, the unjoined region Ae is formed by silylation of the outer peripheral portion Fwe of the oxide film Fw. It is not limited to this form. For example, it is also possible to hydrophobize the Fwe at the outer periphery by giving a methyl group to the dangling bond as described above. In addition, for example, a release agent may be supplied to the peripheral portion Fwe of the oxide film Fw.

In addition, according to the above-mentioned first to third embodiments, the wafer W to be processed is thinned by grinding the back surface Wb of the processing device, but the method of thinning the wafer W to be processed is not limited to this a form. For example, as shown in FIG. 31( a ), inside the wafer W to be processed, an inner surface modification layer M3 is formed along the surface direction of the edge modification layer M1 and the wafer W to be processed. In addition, the formation order of the edge modified layer M1 and the inner surface modified layer M3 can be determined arbitrarily. Then, as shown in FIG. 31(b), the edge trimming of the processed wafer W starting from the edge modified layer M1 and the back surface Wb side of the processed wafer W starting from the inner surface modified layer M3 are performed. separate. In this way, the wafer W to be processed can be thinned by separating the back surface Wb side using the inner surface modified layer M3 as a starting point.

As described above, in the wafer processing of the present embodiment, since the unjoined region Ae is formed in the outer peripheral portion Fwe, the re-densification of the outer peripheral portion Fwe is suppressed, and the peeling of the peripheral portion We can be performed appropriately. In addition, the thinning of the wafer W to be processed is performed by the separation based on the inner surface modified layer M3 in this way, thereby eliminating the need to perform grinding of the rear surface Wb and end surfaces for thinning and edge trimming as in the prior art. . That is, there is no need to generate grinding dust during thinning and edge trimming of the wafer W to be processed, and it is not necessary to install a grinding tool that is a consumable, so that the configuration of the device can be simplified.

In addition, in the case of thinning the wafer W to be processed by forming the inner surface modifying layer M3 in this way, the thinning and edge trimming of the wafer W to be processed can also be performed at the same time. Specifically, as shown in FIG. 32( a ), the upper end of the edge modified layer M1 and the inner surface modified layer M3 are formed at approximately the same height. Then, in this state, with the edge modified layer M1 and the inner surface modified layer M3 as the base point, the back surface Wb side of the wafer W to be processed is separated, so that the peripheral edge We It is integrated with the wafer on the backside Wb side and removed.

In this edge trimming method, as described above, in the wafer processing of the present embodiment, the non-joined region Ae is formed on the outer peripheral portion Fwe, so that the re-densification of the outer peripheral portion Fwe is suppressed, and the peeling of the peripheral portion We can be performed appropriately. . In addition, in the past, grinding for thinning the wafer W to be processed and grinding for edge trimming were performed separately, but in this embodiment, thinning and edge trimming of the wafer W to be processed can be performed simultaneously. In addition, as mentioned above, the thinning of the wafer W to be processed is carried out by the separation based on the internal surface modification layer M3, so that it is not necessary to carry out the backside Wb and the end surface for thinning and edge trimming as in the prior art. grind. That is, there is no need to generate grinding dust during thinning and edge trimming of the wafer W to be processed, and it is not necessary to install a grinding tool that is a consumable, so that the configuration of the device can be simplified.

It should be understood that the embodiments disclosed this time are merely examples in all viewpoints, and are not intended to limit the present invention. The above-mentioned embodiments can be omitted, replaced, or changed in various forms without departing from the scope of the appended patent application and the gist thereof.

1. 200‧‧‧wafer processing system 2‧‧‧Moving in and out 3‧‧‧Processing station 10‧‧‧Wafer cassette loading table 20, 30‧‧‧Wafer handling area 21, 31‧‧‧Conveying Road 22, 32‧‧‧Wafer handling device 23, 33‧‧‧Transportation arm 34‧‧‧Transmission device 40‧‧‧Joint device 41‧‧‧Internal modification device 42, 230, 240, 330‧‧‧Surface modification device 43‧‧‧hydrophobic device 50‧‧‧processing device 60‧‧‧rotary table 61, 150, 231, 241, 350‧‧‧suction cup 70‧‧‧Transportation unit 71‧‧‧Robot Arm 72‧‧‧Transfer mat 73‧‧‧Moving mechanism 80‧‧‧alignment unit 90‧‧‧1st cleaning unit 100‧‧‧The second cleaning unit 110‧‧‧coarse grinding unit 111‧‧‧coarse grinding part 112, 122, 132‧‧‧Pillar 120‧‧‧Medium Grinding Unit 121‧‧‧Middle Grinding Department 130‧‧‧fine grinding unit 131‧‧‧Fine Grinding Department 140‧‧‧control device 151, 232, 242, 351‧‧‧rotation mechanism 152, 352‧‧‧Nozzle 210‧‧‧Peripheral removal device 220‧‧‧hydrophilization device 233, 234‧‧‧polishing components 233a‧‧‧The second polishing area 234a‧‧‧1st polishing area 243‧‧‧Laser head 244‧‧‧fluid nozzle 245‧‧‧suction mechanism 300‧‧‧upper suction cup 300a, 300b, 301a, 301b‧‧‧suction port 301‧‧‧Lower suction cup 302‧‧‧Pushing components A0‧‧‧Transfer location A1～A3‧‧‧Processing position Ac‧‧‧junction area Ae‧‧‧unjoined area B‧‧‧Joint Wave Be‧‧‧end C1, C2‧‧‧crack Cs, Ct, Cw‧‧‧wafer cassette D‧‧‧Component layer E‧‧‧etching solution Fs, Fw‧‧‧Oxide film Fwe‧‧‧Peripheral Department Fwe1, Fwe2‧‧‧circular area Fws‧‧‧silanization area G‧‧‧silane material H‧‧‧recording media L, L1, L2, L3‧‧‧distance Lr1, Lr2, Lr3, R‧‧‧laser light M‧‧‧modified layer M1, M1 (1)～(7)‧‧‧edge modified layer M2‧‧‧Split modified layer M3‧‧‧Inner surface modified layer Pt(1)～Pt(n)‧‧‧irradiation point S‧‧‧Support Wafers Sa‧‧‧surface Sb‧‧‧back T‧‧‧overlapping wafer V‧‧‧Edge porosity W‧‧‧Wafer processed Wa‧‧‧surface Wb‧‧‧back Wc‧‧‧central department We‧‧‧peripheral department

FIGS. 1( a ) to ( c ) are explanatory diagrams showing states of conventional bonding processes between wafers. FIG. 2 is a schematic side view showing the configuration of superimposed wafers. 3( a ) to ( e ) are explanatory diagrams showing states of bonding processing between wafers in a bonding apparatus. Fig. 4 is an explanatory diagram showing the mechanism of edge porosity generation. FIG. 5 is an explanatory diagram showing how edge voids are generated in superimposed wafers. Fig. 6 is a plan view schematically showing the configuration of the wafer processing system according to the first embodiment. Fig. 7 is a side view showing a schematic configuration of the surface modifying device. 8( a ) and ( b ) are explanatory diagrams showing the state in which the outer peripheral portion of the oxide film is removed in the surface modifying device, and the wafers are further bonded together. Fig. 9 is a flow chart showing main steps of wafer processing in the first embodiment. 10( a ) to ( e ) are explanatory diagrams showing main steps of wafer processing in the first embodiment. FIG. 11 is an explanatory view showing how a modified layer is formed on a wafer to be processed. 12(a) and (b) are explanatory diagrams showing how an edge modification layer is formed on a wafer to be processed. FIG. 13 is an explanatory view showing the state of forming split modified layers on a wafer to be processed. FIG. 14 is a plan view schematically showing the configuration of a wafer processing system according to a modified example of the first embodiment. Fig. 15 is a plan view schematically showing the configuration of a wafer processing system according to the second embodiment. Fig. 16 is a flow chart showing main steps of wafer processing in the second embodiment. 17( a ) to ( e ) are explanatory diagrams showing main steps of wafer processing in the second embodiment. Fig. 18 is a schematic side view showing the configuration of a surface modifying device according to another embodiment. FIGS. 19( a ) and ( b ) are explanatory diagrams showing a state in which the outer peripheral portion of the oxide film is removed in the surface modifying apparatus shown in FIG. 18 , and wafers are further bonded together. 20( a ) and ( b ) are explanatory diagrams showing a method of controlling the diffusion of debris generated during the removal of the outer peripheral portion of the oxide film of the surface modifying device. 21( a ) and ( b ) are explanatory diagrams showing the difference in machining accuracy of the edge of the peripheral portion due to the diameter of the abrasive grains. Fig. 22 is an explanatory view showing a method of removing the outer periphery of the oxide film of the surface modifying device. Fig. 23 is a schematic side view showing the configuration of a surface modifying device according to yet another embodiment. FIGS. 24( a ) and ( b ) are explanatory diagrams showing a state in which the outer peripheral portion of the oxide film is removed in the surface modifying apparatus shown in FIG. 23 , and wafers are further bonded together. FIG. 25 is a plan view of the surface modifying device shown in schematic diagram 23 in which an oxide film is removed. 26( a ) and ( b ) are side views showing how the oxide film is removed in the surface modifying device shown in schematic diagram 23 . FIG. 27 is an explanatory diagram showing how the outer periphery of the oxide film is removed by another method of the surface modifying device shown in FIG. 23 . Fig. 28 is a side view showing a schematic configuration of a surface modifying device included in the wafer processing system according to the third embodiment. Fig. 29 is a flow chart showing main steps of wafer processing in the third embodiment. 30( a ) to ( d ) are explanatory diagrams showing main steps of wafer processing in the third embodiment. 31( a ) and ( b ) are explanatory diagrams showing how the wafer to be processed is thinned by another method. 32( a ) and ( b ) are explanatory diagrams showing states of edge trimming of a processed wafer by another method.

1‧‧‧Wafer processing system

2‧‧‧Moving in and out

3‧‧‧Processing station

10‧‧‧Wafer cassette loading table

20, 30‧‧‧Wafer handling area

21, 31‧‧‧Conveying Road

22, 32‧‧‧Wafer handling device

23, 33‧‧‧Transportation arm

34‧‧‧Transmission device

40‧‧‧Joint device

41‧‧‧Internal modification device

42‧‧‧Surface modification device

43‧‧‧hydrophobic device

50‧‧‧processing device

60‧‧‧rotary table

61‧‧‧Sucker

70‧‧‧Transportation unit

71‧‧‧Robot Arm

72‧‧‧Transfer mat

73‧‧‧Moving mechanism

80‧‧‧alignment unit

90‧‧‧1st cleaning unit

100‧‧‧The second cleaning unit

110‧‧‧coarse grinding unit

111‧‧‧coarse grinding part

112, 122, 132‧‧‧Pillar

120‧‧‧Medium Grinding Unit

121‧‧‧Middle Grinding Department

130‧‧‧fine grinding unit

131‧‧‧Fine Grinding Department

140‧‧‧control device

A0‧‧‧Transfer location

A1~A3‧‧‧Processing position

Cs, Ct, Cw‧‧‧wafer cassette

S‧‧‧Support Wafers

T‧‧‧overlapping wafer

W‧‧‧Wafer processed

Claims (15)

A substrate processing system for processing a substrate, comprising: a surface modifying device for bonding a first surface film formed on a surface of a first substrate to a second surface film formed on the surface of a second substrate The outer periphery is modified; the surface modification device roughens the outer periphery of the first surface film. The substrate processing system of claim 1 of the scope of the patent application, which further includes: a bonding device, which uses the surface modification device to modify the first surface film of the first substrate on the outer periphery, and the second The second surface film formed on the surface of the substrate is bonded. In the substrate processing system according to claim 2 of the patent application, the bonding device is a hydrogen bonding device. The substrate processing system according to any one of claims 1 to 3 of the patent claims, wherein the surface modifying device removes the outer peripheral portion of the first surface film. The substrate processing system as claimed in claim 4 of the scope of the patent application, wherein the surface modifying device is such that the outer peripheral portion of the first surface film is such that the thickness of the first surface film decreases radially outward in a side view way to remove. For example, the substrate processing system of item 1 of the scope of the patent application, wherein, In the surface modifying device, the outer peripheral portion of the first surface film is raised. The substrate processing system according to claim 1, wherein the surface modifying device roughens the outer peripheral portion of the first surface film so that the surface roughness of the first surface film increases radially outward change. A substrate processing method for processing a substrate, comprising the steps of: modifying the outer periphery of a first surface film formed on a surface of a first substrate before being bonded to a second surface film formed on the surface of a second substrate and bonding the first surface film of the first substrate modified on the outer periphery to the second surface film formed on the surface of the second substrate. The substrate processing method according to claim 8 of the patent application, wherein the joining is hydrogen bonding. The substrate processing method according to claim 8 or 9, wherein, in modifying the outer peripheral portion of the first surface film, the outer peripheral portion of the first surface film is removed. Such as the substrate processing method of claim 10, wherein, in modifying the outer peripheral portion of the first surface film, the outer peripheral portion of the first surface film is such that the thickness of the first surface film is viewed from a side view It is removed in a way that decreases radially outward. The substrate processing method according to claim 8 or 9, wherein, in modifying the outer peripheral portion of the first surface film, the outer peripheral portion of the first surface film is raised. The substrate processing method according to claim 8 or 9, wherein, in modifying the outer peripheral portion of the first surface film, the outer peripheral portion of the first surface film is roughened. Such as the substrate processing method of claim 13, wherein, in modifying the outer peripheral portion of the first surface film, the outer peripheral portion of the first surface film is made to make the surface roughness of the first surface film toward Roughening in a radially outward increasing manner. The substrate processing method according to claim 8 or 9, wherein, in modifying the outer peripheral portion of the first surface film, the outer peripheral portion of the first surface film is silanized.

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