JP7058737B2 - Board processing system and board processing method - Google Patents

Description

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

Patent Document 1 discloses a bonding device for two wafers. In the bonding device, first, of the two wafers arranged so as to face each other in the vertical direction, the central portion of the upper wafer is pressed by the push pin to bring the central portion into contact with the lower wafer. After that, 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 joined to each other.

Patent Document 2 discloses an end face grinding device that grinds a peripheral end portion of a semiconductor wafer. In the end face grinding device, a disk-shaped grinding tool provided with abrasive grains on the outer peripheral portion is rotated, and at least the outer peripheral surface of the grinding tool is linearly contacted with the semiconductor wafer to form a substantially L peripheral end portion of the semiconductor wafer. Grind in a shape. A semiconductor wafer is manufactured by laminating two silicon wafers.

Japanese Unexamined Patent Publication No. 2004-207436 Japanese Unexamined Patent Publication No. 9-216152

The technique according to the present disclosure suppresses voids generated in the peripheral portion of the substrate when the substrates are joined to each other.

One aspect of the present disclosure is a substrate processing system for processing a substrate, which is formed on the surface of the first substrate before being bonded to the second surface film formed on the surface of the second substrate. It has a surface reforming device for modifying the outer peripheral portion of the first surface film, and the surface modifying device has the first surface with the outer peripheral portion of the first surface film directed outward in the radial direction. The surface of the film is roughened so that the surface roughness becomes large .

According to the present disclosure, it is possible to suppress voids generated in the peripheral portion of the substrate when the substrates are joined to each other.

It is explanatory drawing which shows the state of the state of the conventional bonding process between wafers. It is a side view which shows the outline of the structure of a polymerization wafer. It is explanatory drawing which shows the state of the state of the bonding process between wafers in a bonding apparatus. It is explanatory drawing which shows the mechanism which the edge void occurs. It is explanatory drawing which shows the appearance that the edge void was generated in the polymerized wafer. It is a top view schematically showing the outline of the structure of the wafer processing system which concerns on 1st Embodiment. It is a side view which shows the outline of the structure of the surface modification apparatus. It is explanatory drawing which shows the state which removes the outer peripheral part of the oxide film in a surface modification apparatus, and further joins wafers together. It is a flow diagram which shows the main process of the wafer processing which concerns on 1st Embodiment. It is explanatory drawing of the main process of the wafer processing which concerns on 1st Embodiment. It is explanatory drawing which shows the appearance which the modified layer was formed on the wafer to be processed. It is explanatory drawing which shows the state which the peripheral modification layer is formed on the wafer to be processed. It is explanatory drawing which shows the mode that the division reforming layer is formed on the wafer to be processed. It is a top view schematically showing the outline of the structure of the wafer processing system which concerns on the modification of 1st Embodiment. It is a top view schematically showing the outline of the structure of the wafer processing system which concerns on 2nd Embodiment. It is a flow diagram which shows the main process of the wafer processing which concerns on 2nd Embodiment. It is explanatory drawing of the main process of the wafer processing which concerns on 2nd Embodiment. It is a side view which shows the outline of the structure of the surface modification apparatus which concerns on other embodiment. It is explanatory drawing which shows the mode that the outer peripheral part of the oxide film is removed, and the wafers are bonded to each other in the surface modification apparatus shown in FIG. It is explanatory drawing which shows typically the method of controlling the diffusion of debris generated in the removal of the outer peripheral part of an oxide film in a surface modification apparatus. It is explanatory drawing which shows typically the difference of the processing accuracy of the edge part of the peripheral part by the abrasive grain size. It is explanatory drawing which shows typically the method of removing the outer peripheral part of an oxide film in a surface modification apparatus. It is a side view which shows the outline of the structure of the surface modification apparatus which concerns on still another Embodiment. It is explanatory drawing which shows the state which removes the outer peripheral part of the oxide film, and further joins wafers with each other in the surface modification apparatus shown in FIG. 23. It is a top view which shows the state of removal of the oxide film in the surface modification apparatus shown in FIG. 23 schematically. It is a side view schematically showing the state of removal of an oxide film in the surface modification apparatus shown in FIG. 23. It is explanatory drawing which shows the state of removal of the outer peripheral part of the oxide film by another method in the surface modification apparatus shown in FIG. 23 schematically. It is a side view which shows the outline of the structure of the surface reforming apparatus provided in the wafer processing system which concerns on 3rd Embodiment. It is a flow diagram which shows the main process of the wafer processing which concerns on 3rd Embodiment. It is explanatory drawing of the main process of the wafer processing which concerns on 3rd Embodiment. It is explanatory drawing which shows the state of thinning of the wafer to be processed by another method schematically. It is explanatory drawing which shows the state of the edge trim of the wafer to be processed by another method schematically.

In a three-dimensional integration technique for stacking semiconductor devices in three dimensions, two semiconductor wafers (hereinafter referred to as wafers) are joined. Specifically, for example, wafers are bonded to each other by van der Waals force and hydrogen bond (intermolecular force). Then, the bonding of the wafer is performed by, for example, the bonding device disclosed in Patent Document 1.

Further, in the manufacturing process of a semiconductor device, among the bonded polymerized wafers, the back surface of the wafer in which devices such as a plurality of electronic circuits are formed on the front surface is ground to thin the wafer. .. Normally, the peripheral edge of the wafer is chamfered, but when the wafer is ground in this way, the peripheral edge of the wafer becomes a sharply pointed shape (so-called knife edge shape). Then, chipping occurs at the peripheral edge of the wafer, and the wafer may be damaged. Therefore, so-called edge trimming is performed in which the peripheral edge of the wafer is shaved in advance before the grinding process. Then, this edge trim is performed by, for example, the end face grinding apparatus disclosed in Patent Document 2.

Here, in order to properly join the wafers, it is necessary to satisfy various criteria, and one of the important criteria is the suppression of voids. In particular, it is difficult to control the voids (hereinafter referred to as edge voids) generated in the peripheral portion of the bonded polymerized wafer, and it is required to suppress the edge voids.

The state in which edge voids are generated in the polymerized wafer as described above will be illustrated and described with reference to FIG. Here, the wafer W to be processed and the support wafer S are joined. As will be described later, the device 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. 1A, the surface Wa of the peripheral edge portion We of the wafer W to be processed is removed (edge trim). After that, as shown in FIG. 1B, the edge-trimmed wafer W to be processed and the support wafer S are joined. At this time, in the bonded polymerized wafer T, the above-mentioned edge void V is formed between the oxide films Fw and Fs. Then, as shown in FIG. 1 (c), the back surface Wb of the wafer W to be processed is ground in the polymerized wafer T.

When the edge void V is generated in the polymerized wafer T, for example, when the back surface Wb of the wafer W to be processed shown in FIG. 1C is ground, the edge void V may cause peeling of the wafer W to be processed. Further, cracks, chipping, etc. may occur in the wafer W to be processed from this peeling as a starting point. Further, for example, in the polymerized wafer T, metal vias and pads are formed on the respective wafers W and S, and these vias and pads may be connected by diffusion bonding. In such a case, if edge voids are generated at the locations of vias and pads, diffusion bonding does not occur and connection failure may occur.

Further, when the edge void V is generated in the polymerized wafer T, the effective region (usable region) of the wafer W to be processed becomes smaller. As shown in FIG. 1, for example, the distance L1 from the end portion of the wafer W to be processed before processing to the inner end portion of the edge void V was about 7 mm. Therefore, when the diameter of the wafer W to be processed before processing is 300 mm, the effective region is a region of φ286 mm.

When edge voids are generated in this way, the yield of the product is lowered. However, in the past, including the bonding device disclosed in Patent Document 1, it has been a problem to suppress this edge void.

Therefore, the technique according to the present disclosure suppresses edge voids when joining wafers to each other. Specifically, the present disclosers elucidated the mechanism of edge void generation, and based on that finding, came up with a system and method for suppressing edge voids.

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

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

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

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

First, the mechanism of edge void generation will be described. In joining the wafer W to be processed and the support wafer S, first, the surfaces of the oxide films Fw and Fs are activated by plasma treatment in a reduced pressure atmosphere before joining. After that, the activated surface is hydrophilized, and an OH group (hydroxy group) is imparted to the dangling bond formed on the surface. Then, at the time of bonding, the oxide films Fw and Fs come into contact with each other and the OH groups are hydrogen-bonded, so that the oxide films Fw and Fs are bonded to each other. Water is removed from the bonded oxide films Fw and Fs by further annealing treatment, and the bonding strength thereof is ensured.

In the joining device, as shown in FIG. 3A, the wafer W to be processed is adsorbed and held by the upper chuck 300, and the support wafer S is adsorbed and held by the lower chuck 301. The upper chuck 300 can suck the wafer W to be processed independently from the suction ports 300a and 300b, and the lower chuck 301 can also suck the support wafer S independently from the suction ports 301a and 301b. After that, as shown in FIG. 3B, the suction from the suction port 300a in the central portion is stopped, the pushing member 302 provided in the upper chuck 300 is lowered, and the central portion of the wafer W to be processed is pressed. To. Then, the central portion of the wafer W to be processed and the central portion of the support wafer S come into contact with each other, bonding by hydrogen bonding starts, and a so-called bonding wave B is generated. Subsequently, as shown in FIG. 3C, the bonding wave B diffuses from the central portion to the peripheral portion. When the bonding wave B reaches the peripheral edge portion, suction from the suction port 300b of the peripheral edge portion is stopped as shown in FIG. 3D, and the peripheral edge portion of the wafer W to be processed falls on the support wafer S. Then, as shown in FIG. 3 (e), the wafer W to be processed and the support wafer S are joined.

Here, as shown in FIG. 4, at the end Be of the bonding wave B, the air is compressed in the space between the wafers W and S, and the pressure becomes high. Further, at the peripheral portion of the wafers W and S, for example, 1 mm to 5 mm from the end portion, the atmosphere compressed by the end portion Be of the bonding wave B and becoming high pressure (for example, 3 times the atmospheric pressure) is released to the atmosphere and rapidly. It will be decompressed to atmospheric pressure. Then, at the peripheral portions of the wafers W and S, the Joule-Thomson effect is generated by this rapid depressurization, the temperature is lowered (for example, the temperature is lowered by 1.5 ° C.), and dew condensation is generated. When the wafers W and S are joined, this dew condensation is confined at the interface between the oxide films Fw and Fs. After that, when the annealing treatment is performed, the water existing at the interface evaporates and expands to form a void, and as shown in FIG. 5, an annular edge void V is generated at the peripheral edge of the polymerized wafer T.

As described above, the present disclosers have found that edge voids are generated by a sudden pressure change between the wafers W and S. Therefore, the present disclosures have come up with the idea of suppressing this sudden pressure change and suppressing edge voids. Hereinafter, the wafer processing system as the substrate processing system and the wafer processing method as the substrate processing method according to the present embodiment will be described with reference to the drawings. In the present specification and the drawings, the elements having substantially the same functional configuration are designated by the same reference numerals, so that duplicate description will be omitted.

First, the configuration of the wafer processing system according to the first embodiment will be described. FIG. 6 is a plan view schematically showing an outline of the configuration of the wafer processing system 1. In the wafer processing system 1 according to the first embodiment, edge trimming is performed after joining.

The wafer processing system 1 has a configuration in which the loading / unloading station 2 and the processing station 3 are integrally connected. For example, cassettes Cw, Cs, and Ct capable of accommodating a plurality of wafers W to be processed, a plurality of support wafers S, and a plurality of polymerized wafers T, respectively, are carried in and out of the carry-in / out station 2. The processing station 3 includes various processing devices that perform predetermined processing on the wafer W to be processed, the support wafer S, and the polymerization wafer T.

The loading / unloading station 2 is provided with a cassette mounting table 10. In the illustrated example, a plurality of, for example, four cassettes Cw, Cs, and Ct can be freely placed in a row on the cassette mounting table 10 in the Y -axis direction. The number of cassettes Cw, Cs, and Ct mounted on the cassette mounting table 10 is not limited to this embodiment and can be arbitrarily determined.

The loading / unloading station 2 is provided with a wafer transport area 20 adjacent to the cassette mounting table 10. The wafer transfer region 20 is provided with a wafer transfer device 22 that is movable on a transfer path 21 extending in the Y -axis direction. The wafer transfer device 22 has, for example, two transfer arms 23, 23 that hold and transfer the wafer W to be processed, the support wafer S, and the polymerized wafer T. Each transport arm 23 is configured to be movable in the horizontal direction, the vertical direction, the horizontal axis, and the vertical axis . The configuration of the transfer arm 23 is not limited to this embodiment, and any configuration may be adopted.

The processing station 3 is provided with a wafer transfer area 30. The wafer transfer region 30 is provided with a wafer transfer device 32 that is movable on a transfer path 31 extending in the X-axis direction. The wafer transfer device 32 has a transition device 34, a joining device 40, an internal reforming device 41, a surface reforming device 42, a hydrophobicization device 43, and a processing device 50, which will be described later, with respect to a wafer W to be processed, a support wafer S, and polymerization. The wafer T is configured to be transportable. Further, the wafer transfer device 32 has, for example, two transfer arms 33, 33 that hold and transfer the wafer W to be processed, the support wafer S, and the polymerized wafer T. Each transport arm 33 is configured to be movable in the horizontal direction, the vertical direction, the horizontal axis, and the vertical axis . The configuration of the transfer arm 33 is not limited to this embodiment, and any configuration can be adopted.

A transition device 34 for delivering the wafer W to be processed, the support wafer S, and the polymerized wafer T is provided between the wafer transfer region 20 and the wafer transfer region 30.

On the Y-axis positive direction side of the wafer transfer region 30, the joining device 40 and the internal reforming device 41 are arranged side by side in the X-axis direction from the loading / unloading station 2 side. On the Y-axis negative direction side of the wafer transfer region 30, the surface reforming device 42 and the hydrophobizing device 43 are arranged side by side in the X-axis direction from the loading / unloading station 2 side.

The joining device 40 joins the oxide film Fw of the wafer W to be processed and the oxide film Fs of the support wafer S. Prior to joining, the oxide film Fw and the oxide film Fs are each activated and hydrophilized. Specifically, when the oxide film Fw and the oxide film Fs are activated, oxygen gas or nitrogen gas, which is a processing gas, is excited to be plasma-generated and ionized, for example, in a reduced pressure atmosphere. The oxygen ion or nitrogen ion is irradiated to the oxide film Fw and the oxide film Fs, and the oxide film Fw and the oxide film Fs are plasma-treated and activated. Further, pure water is supplied to the oxide film Fw and the oxide film Fs activated in this manner, and an OH group is added to the dangling bond of 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, the bonded polymerized wafer T is annealed to remove water from the oxide film Fw and the oxide film Fs to secure the bonding strength.

The internal reformer 41 forms a peripheral reforming layer and a split reforming layer inside the wafer W to be processed. In the internal reformer 41, the polymerized wafer T is rotated and held by a chuck (not shown), and the inside of the wafer W to be processed is irradiated with laser light from a laser head (not shown). The laser head is a high-frequency pulsed laser beam oscillated from a laser beam oscillator (not shown), and is subject to laser light having a wavelength that is transparent to the wafer W to be processed, for example, infrared light. The light is focused and irradiated at a predetermined position inside the processing wafer W. As a result, the portion where the laser beam is focused is modified inside the wafer W to be processed. As will be described later, the peripheral modification layer is formed on the wafer W to be processed along the boundary between the peripheral portion We to be removed and the central portion. Further, as will be described later, the split reforming layer is formed by extending in the radial direction on the radial outer side of the peripheral modification layer.

Further, the laser head further has a spatial light modulator (not shown). The spatial light modulator modulates and outputs the laser beam. Specifically, the spatial light modulator can control the focal position and phase of the laser beam, and can adjust the shape and number (number of branches) of the laser beam irradiated to the wafer W to be processed.

The surface modification 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 the present embodiment. In the surface modifier 42, wet etching is performed on the outer peripheral portion of the oxide film Fw with an etching solution such as hydrofluoric acid.

The hydrophobizing device 43 immerses the polymerized wafer T in an organic solvent to bond, for example, _three CH groups (methyl groups) to the surfaces of the unbonded oxide films Fw and Fs. The interface between the oxide films Fw and Fs bonded by the bonding device 40 corresponds to the bonding region to which the oxide films Fw and Fs are bonded and the oxide film Fw removed by the surface modification device 42, as will be described later. An unbonded region is formed. In the hydrophobizing device 43, for example, _three CH groups are bonded to the dangling bond formed on the surface of the oxide films Fw and Fs in the unbonded region to make the hydrophobizing device 43. The hydrophobization of the surfaces of the oxide films Fw and Fs is not limited to the bonding of _three CH groups, and for example, other carbon-containing groups may be bonded to the surface of the oxide films Fw and Fs. Further, in the present embodiment, the polymerized wafer T is immersed in an organic solvent, but the method of imparting _three CH groups is not limited to this, 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 arranged on the X-axis positive direction side of the wafer transfer region 30. In the processing apparatus 50, processing such as grinding and cleaning is performed on the wafer W to be processed.

The processing apparatus 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 medium grinding unit 120, and a finishing grinding unit 130. There is.

The rotary table 60 is rotatably configured by a rotary mechanism (not shown). Four chucks 61 for sucking and holding the polymerized wafer T are provided on the rotary table 60. The chucks 61 are arranged evenly on the same circumference as the rotary table 60, that is, every 90 degrees. The four chucks 61 can be moved to the delivery position A0 and the processing positions A1 to A3 by rotating the rotary table 60. The chuck 61 is held by a chuck base (not shown) and is rotatably configured by a rotation mechanism (not shown).

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

The transport unit 70 is an articulated robot provided with a plurality of, for example, three arms 71. Each of the three arms 71 is configured to be rotatable. A transport pad 72 that attracts and holds the polymerized wafer T is attached to the arm 71 at the tip. Further, the arm 71 at the base end is attached to a moving mechanism 73 that moves the arm 71 in the vertical direction. Then, the transfer unit 70 having such a configuration can transfer the polymerized wafer T to the delivery position A0, the alignment unit 80, the first cleaning unit 90, and the second cleaning unit 100.

The alignment unit 80 adjusts the horizontal orientation of the polymerized wafer T before the grinding process. For example, the position of the notch portion of the wafer W to be processed is adjusted by detecting the position of the notch portion of the wafer W to be processed by the detection unit (not shown) while rotating the polymerized wafer T held by the chuck (not shown). The horizontal orientation of the polymerized wafer T is adjusted.

In the first cleaning unit 90, the back surface Wb of the wafer W to be processed after the grinding process is cleaned, and more specifically, spin cleaning is performed.

The second cleaning unit 100 cleans the back surface Sb of the support wafer S in a state where the wafer W to be processed after the grinding process is held by the transport pad 72, and also cleans the transport pad 72.

The rough grinding unit 110 roughly grinds the back surface of the wafer W to be processed. The rough grinding unit 110 has a rough grinding unit 111 having an annular shape and a rotatable rough grinding wheel (not shown). Further, the rough grinding portion 111 is configured to be movable in the vertical direction and the horizontal direction along the support column 112. Then, with the back surface of the wafer W to be processed held by the chuck 61 in contact with the rough grinding wheel, the chuck 61 and the rough grinding wheel are each rotated, and the rough grinding wheel is further lowered to lower the wafer to be processed. Roughly grind the back surface of W.

In the medium grinding unit 120, the back surface of the wafer W to be processed is medium ground. The medium grinding unit 120 has a medium grinding unit 121 having an annular shape and a rotatable medium grinding wheel (not shown). Further, the middle grinding portion 121 is configured to be movable in the vertical direction and the horizontal direction along the support column 122. The grain size of the grindstone of the medium grinding wheel is smaller than the grain size of the grindstone of the coarse grinding wheel. Then, with the back surface of the wafer W to be processed held by the chuck 61 in contact with the medium grinding wheel, the chuck 61 and the medium grinding wheel are each rotated, and the medium grinding wheel is further lowered to lower the back surface. Grind.

The finish grinding unit 130 finish grinds the back surface of the wafer W to be processed. The finish grinding unit 130 has a finish grinding unit 131 having an annular shape and a rotatable finish grinding wheel (not shown). Further, the finish grinding unit 131 is configured to be movable in the vertical direction and the horizontal direction along the support column 132. The particle size of the abrasive grains of the finishing grinding wheel is smaller than the particle size of the abrasive grains of the medium grinding wheel. Then, with the back surface of the wafer W to be processed held by the chuck 61 in contact with the finishing grinding wheel, the chuck 61 and the finishing grinding wheel are each rotated, and the finishing grinding wheel is further lowered to finish the back surface. Grind.

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

The wafer processing system 1 described above is provided with a control device 140. The control device 140 is, for example, a computer and has a program storage unit (not shown). A program for controlling wafer processing in the wafer processing system 1 is stored in the program storage unit. Further, the program storage unit also stores a program for controlling the operation of the drive system of the above-mentioned various processing devices and transfer devices to realize the wafer processing described later in the wafer processing system 1. The program may be recorded on a storage medium H readable by a computer and may be installed on the control device 140 from the storage medium H.

Next, the surface modification device 42 will be described. As shown in FIG. 7, the surface reformer 42 has a chuck 150 that holds the wafer W to be processed with the oxide film Fw facing upward. The chuck 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 etching solution E to the outer peripheral portion of the oxide film Fw is provided. The nozzle 152 communicates with an etching solution supply source (not shown) that stores and supplies the etching solution E. Further, 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).

In the surface modifier 42, as shown in FIG. 8A, the surface layer of the outer peripheral portion Fwe of the oxide film Fw is removed by the etching solution E. Then, as shown in FIG. 8B, the oxide films Fw and Fs are not bonded at the time of the bonding process in the outer peripheral portion Fwe. That is, when the oxide films Fw and Fs are bonded, an unbonded region Ae corresponding to the bonded region Ac to which the oxide films Fw and Fs are bonded and the outer peripheral portion Fwe is formed at the interface between the oxide films Fw and Fs. To.

Here, as described above with reference to FIG. 4, a high-pressure atmosphere is formed at the end of the bonding wave, and this atmosphere is opened to the atmosphere and rapidly reduced to atmospheric pressure, so that edge voids are generated. In this respect, in the present embodiment, since the unbonded region Ae is formed, the space where the high-pressure atmosphere at the end of the bonding wave is released becomes small, and the pressure is not reduced to the atmospheric pressure. By suppressing the sudden depressurization in this way, the edge void can be suppressed.

Further, it is desirable that the thickness H of the outer peripheral portion Fwe to be removed, which is shown in FIG. 8, is within 400 nm from the surface. As the thickness H of the outer peripheral portion Fwe becomes larger than 400 nm, the space where the atmosphere at the end of the bonding wave is opened becomes larger, and the degree of decompression becomes larger. Therefore, it is preferable that the thickness H of the outer peripheral portion Fwe is small. Then, when the present disclosers conducted an experiment, it was confirmed that the edge void could be reliably suppressed if the thickness H of the outer peripheral portion Fwe was within 400 nm.

Further, the width La of the unjoined region Ae shown in FIG. 8 is, for example, within 4 mm. It should be noted that this width La does not contribute to the generation of edge voids, and even if the width La is as large as 4 mm, for example, edge voids can be suppressed. However, as will be described later, in order to increase the effective area of the wafer W to be processed, it is preferable that the width La is as small as possible.

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

First, the cassette Cw containing the plurality of wafers W to be processed and the cassette Cs containing the plurality of support wafers S are placed on the cassette mounting table 10 of the loading / unloading station 2.

Next, the wafer transfer device 22 takes out the wafer W to be processed in the cassette Cw and transfers it to the transition device 34. Subsequently, the wafer transfer device 32 takes out the wafer W to be processed of the transition device 34 and transfers it to the surface reforming device 42. In the surface reformer 42, the etching solution E is supplied to the outer peripheral portion Fwe of the oxide film Fw of the wafer W to be processed, and the surface layer of the outer peripheral portion Fwe is removed as shown in FIG. 10A (step of FIG. 9). P1). At this time, the outer peripheral portion Fwe is removed so that the distance L2 from the end portion of the wafer W to be processed is about 0.5 mm.

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

Next, the wafer W to be processed is transferred to the joining device 40 by the wafer transfer device 32. At this time, the front and back surfaces of the wafer W to be processed are inverted by the wafer transfer device 22 or the inversion device (not shown). In the joining device 40, as shown in FIG. 10B, the oxide film Fw of the wafer W to be processed and the oxide film Fs of the support wafer S are joined to form the polymerized wafer T (step P2 in FIG. 9). At this time, the oxide films Fw and Fs are not bonded at the outer peripheral portion Fwe, and the bonded region Ac and the unbonded region Ae are formed at the interface between the oxide films Fw and Fs. Then, the unbonded region Ae reduces the space where the high-pressure atmosphere at the end of the bonding wave is released, and the pressure is not reduced to the atmospheric pressure. By suppressing the sudden depressurization in this way, the edge void can be suppressed.

Next, the polymerized wafer T is transferred to the hydrophobizing device 43 by the wafer transfer device 32. In the hydrophobizing apparatus 43, the polymerized wafer T is immersed in an organic solvent to bond _three CH groups to the surfaces of the oxide films Fw and Fs in the unbonded region Ae as shown in FIG. 10 (c) (step 9). P3). By making the surfaces of the oxide films Fw and Fs in the unbonded region Ae hydrophobic in this way, for example, it is possible to suppress the adhesion (bonding) of the oxide films Fw and Fs by water vapor in the atmosphere after the bonding treatment. can. Therefore, edge voids can be suppressed more reliably. Further, if the oxide films Fw and Fs are in close contact with each other, it may not be possible to properly remove the peripheral portion We of the wafer W to be processed in step P5 described later, but this can be achieved by making the surfaces of the oxide films Fw and Fs hydrophobic. The peripheral portion We can be appropriately removed. Depending on the humidity of the surrounding environment such as a dry environment, the oxide films Fw and Fs may not adhere to each other after the joining treatment. In such a case, step P3 becomes unnecessary and can be omitted.

Next, the polymerized wafer T is transferred to the internal reformer 41 by the wafer transfer device 32. The internal reformer 41 irradiates the inside of the wafer W to be processed with laser light from the laser head while rotating the wafer W to be processed. Then, as shown in FIGS. 10D and 11, an annular peripheral edge modification layer M1 is formed inside the wafer W to be processed along the boundary between the peripheral edge portion We and the central portion Wc of the wafer to be processed W. (Step P4 in FIG. 9). It is preferable that the peripheral modification layer M1 is formed so as to coincide with the boundary between the bonded region Ac and the unbonded region Ae, or radially inside the boundary. In the illustrated example, the peripheral modification layer M1 is formed at seven locations in the thickness direction of the wafer W to be processed, but the number of the peripheral modification layers M1 is arbitrary.

In forming the peripheral modification layer M1, the laser light emitted from the laser head is switched by the spatial light modulator, and the shape and number thereof are adjusted. Specifically, first, as shown in FIG. 12A, the surface Wa side in the thickness direction of the wafer W to be processed is irradiated with the laser beam Lr1 to irradiate the peripheral modification layers M1 (1) to (3). To form. The number of focusing points of the laser beam Lr1 is one (single focus processing). Next, as shown in FIG. 12B, on the upper side of the peripheral modification layer M1 (3), that is, on the back surface Wb side in the thickness direction of the wafer W to be processed, the peripheral modification layers M1 (4) to ( 7) is formed. The number of focusing points of the laser beam Lr2 is, for example, two, that is, the peripheral modification layers M1 (4), (5) or the peripheral modification layers M1 (6), (7) are formed at the same time. (Multifocal processing).

The number of peripheral modification layers M1 formed by the laser beams Lr1 and Lr2 and the number of condensing points of the laser beams Lr1 and Lr2 are arbitrary. However, in the peripheral modification layers M1 (1) to (3) formed on the device layer D side of the wafer W to be processed, cracks extending in the direction of the device layer D are controlled, that is, the device layer D is damaged. It is preferable that the peripheral modification layer M1 is formed with high accuracy by the single focus processing in order to suppress the application. On the other hand, since the peripheral modification layers M1 (4) to (7) are less likely to damage the device layer D than the peripheral modification layers M1 (1) to (3), the multifocal processing is performed. Thereby, the throughput in the internal reformer 41 can be improved.

Next, the laser head is moved to irradiate the inside of the wafer W to be processed with the laser beam from the laser head. Then, as shown in FIGS. 10D and 11, a split reforming layer M2 extending in the radial direction of the wafer W to be processed is formed on the radial outer side of the peripheral modification layer M1 (step P4 in FIG. 9). ). In the illustrated example, the divided and modified layers M2 are formed at eight locations in the circumferential direction and seven locations in the thickness direction of the wafer W to be processed, but the number of the divided modified layers M2 is arbitrary.

In forming the split reforming layer M2, the laser beam emitted from the laser head is switched by the spatial light modulator, and the shape and number thereof are adjusted. Specifically, as shown in FIG. 13, the inside of the wafer W to be processed is irradiated with the laser beam Lr3 to form the split reforming layer M2. The number of focusing points of the laser beam Lr3 is, for example, two (multifocal processing).

The number of divisional reforming layers M2 formed by the laser beam Lr3 and the number of condensing points of the laser beam Lr3 are arbitrary. Since the split modified layer M2 is formed at a position where it is removed by the subsequent edge trim and is unlikely to damage the device layer D as described above, the internal modification is performed by performing the multifocal processing. The throughput in the quality device 41 can be improved.

Next, the polymerized wafer T is transferred to the processing device 50 by the wafer transfer device 32. The polymerized wafer T conveyed to the processing apparatus is delivered to the alignment unit 80. In the alignment unit 80, the horizontal orientation of the wafer W to be processed is adjusted.

Next, the polymerized wafer T is conveyed from the alignment unit 80 to the delivery position A0 by the transfer unit 70, and is delivered to the chuck 61 at the delivery position A0. After that, the chuck 61 is moved to the first processing position A1. Then, the back surface Wb of the wafer W to be processed is roughly ground by the rough grinding unit 110 (step P5 in FIG. 9).

In the grinding of the back surface Wb, as shown in FIG. 10 (d), the cracks C1 and the cracks C2 are substantially linear in the plate thickness direction from the peripheral modification layer M1 and the split modification layer M2 inside the wafer W to be processed. And reach the back surface Wb and the front surface Wa. Further, as the grinding of the back surface Wb is advanced, the peripheral edge portion We of the wafer W to be processed is peeled off and removed from the peripheral edge modification layer M1 and the crack C1 as the base points as shown in FIG. 10 (e). Further, at this time, the peripheral portion We is fragmented with the split reforming layer M2 and the crack C2 as the base points, and the peripheral portion We can be removed more easily. In the grinding of the back surface Wb, the unbonded region Ae is formed at the interface between the oxide films Fw and Fs, so that the peripheral portion We can be appropriately removed.

Further, the distance L2 between the end portion of the wafer W to be processed before the treatment in step P1 and the end portion of the wafer W to be processed after the treatment in step P5 can be set to about 0.5 mm. That is, the effective region is a region of φ299 mm. Therefore, the effective area can be made larger than that of the conventional method shown in FIG. In this embodiment, edge voids can be suppressed, so that the effective region can be increased. Further, in step P5, since the peripheral edge portion We can be removed with the peripheral edge modification layer M1 as a base point, the width (trim width) of the peripheral edge portion We can be reduced to further increase the effective area. For example, when edge trimming is performed using a grinding tool (blade) as in the conventional case, a trim width of about 2 mm is required, but in this embodiment, the grinding tool is not used and the trim width can be reduced.

Next, the chuck 61 is moved to the second processing position A2. Then, the back surface Wb of the wafer W to be processed is medium-ground by the medium-grinding unit 120. If 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 medium grinding unit 120.

Next, the chuck 61 is moved to the third machining position A3. Then, the back surface Wb of the wafer W to be processed is finished and ground by the finish grinding unit 130.

Next, the chuck 61 is moved to the delivery position A0. Here, the back surface Wb of the wafer W to be processed is roughly cleaned by the cleaning liquid using a cleaning liquid nozzle (not shown). At this time, cleaning is performed to remove dirt on the back surface Wb to some extent.

Next, the polymerized wafer T is conveyed from the delivery 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 by the transport pad 72.

Next, the polymerized 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 and cleaned with the cleaning liquid using a cleaning liquid nozzle (not shown). At this time, the back surface Wb is washed and dried to a desired degree of cleanliness.

After that, the polymerized wafer T that has been subjected to all the processing is conveyed to the transition device 34 by the wafer transfer device 32, and further transferred to the cassette Ct of the cassette mounting table 10 by the wafer transfer device 22. In this way, a series of wafer processing in the wafer processing system 1 is completed.

According to the first embodiment described above, 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, the oxide films Fw and Fs are combined. An unbonded region Ae is formed at the interface. The unbonded region Ae can suppress abrupt depressurization of the atmosphere at the end of the bonding wave, and as a result, can suppress edge voids.

Further, since the CH ₃ groups are bonded to the surface of the oxide films Fw and Fs in the unbonded region Ae in step P3 to make them hydrophobic, it is possible to suppress the adhesion (bonding) of the oxide films Fw and Fs. .. Since the unjoined region Ae can be secured in this way, edge voids can be further suppressed. Further, by hydrophobicizing the surfaces of the oxide films Fw and Fs in the unbonded region Ae, the peripheral portion We of the wafer W to be processed can be appropriately removed in step P5.

Further, in the present embodiment, the effective region of the wafer W to be processed can be increased by suppressing the edge voids. Moreover, in the present embodiment, since the peripheral edge portion We can be removed from the modified layer M as a base point in step P5, the width (trim width) of the peripheral edge 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 end portion of the wafer W to be processed before processing to the edge void V is about 7 mm, and the effective region is a region of φ286 mm. On the other hand, in the present embodiment shown in FIG. 9, the distance L2 between the end portion of the wafer W to be processed before the treatment in step P1 and the end portion of the wafer W to be processed after the treatment in step P5 is about 0. It is 5 mm, and the effective region is a region of φ299 mm. As described above, in the present embodiment, the effective area of the wafer W to be processed can be increased as compared with the conventional case, and a large number of chips as products can be manufactured.

In the present embodiment, after the oxide film Fw and Fs activation treatment, hydrophilization treatment, bonding treatment and annealing treatment are sequentially performed in step P2, the surface of the oxide film Fw and Fs in the unbonded region Ae is performed in step P3. Was made hydrophobic. In this respect, step P3 may be performed between the hydrophilization treatment and the bonding treatment in step P2, or may be performed between the bonding treatment and the annealing treatment.

Further, the wafer processing system 1 of the present embodiment includes a joining device 40, an internal reforming device 41, a surface reforming device 42, a hydrophobizing device 43, and a processing device 50, but the device configuration thereof is arbitrary. For example, the joining device 40 and the surface reforming device 42 may be provided in one system, and the internal reforming device 41, the hydrophobizing device 43, and the processing device 50 may be provided in another system.

Further, for example, as shown in FIG. 14, the wafer processing system 1 is provided with an internal reforming device 41 and a processing device 50, and another system (not shown) includes a joining device 40, a surface reforming device 42, and a hydrophobicization device 43. May be provided.

In such a case, as shown in FIG. 14, a cassette Ct capable of accommodating a plurality of polymerized wafers T is carried in and out to the carry-in / out station 2 of the wafer processing system 1. These cassettes Ct can be freely placed in a row on the cassette mounting table 10 in the Y -axis direction. Further, the processing station 3 is provided with a processing device 50 adjacent to the wafer transfer region 20. The internal reformer 41 is provided inside the processing device 50 on the Y-axis positive direction side of the transport unit 70 and on the X-axis negative direction side of the finish grinding unit 130.

In this example, the polymerized wafer T obtained by performing the above-mentioned steps P1 to P3 in the external system is carried into the carry-in / out station 2 of the wafer processing system 1. That is, the surface layer of the outer peripheral portion Fwe is removed from the polymerized wafer T to be carried in by the surface reforming device 42 (step P1), the oxide films Fw and Fs are joined by the joining device 40 (step P2), and the hydrophobization device is used. At 43, the oxide films Fw and Fs are hydrophobized (step P3). Then, in the wafer processing system 1, steps P4 to P5 are performed on the polymerized wafer T. That is, after the reforming layer M is formed inside the wafer W to be processed by the internal reformer 41 (step P4), the back surface Wb of the wafer W to be processed is ground by the processing apparatus 50, and the peripheral edge We is removed. (Step P5).

Also in this example, the same effect as that of the first embodiment can be enjoyed. That is, since the unbonded region Ae is formed in the polymerized wafer T carried into the wafer processing system 1, edge voids can be suppressed. Then, in this state, the peripheral portion We of the wafer W to be processed can be appropriately removed.

In other words, this example is as follows.
A substrate processing system for processing a substrate, in which a first substrate from which the outer peripheral portion of the surface film is removed within 400 nm from the surface in the thickness direction of the surface film and a second substrate are bonded to a polymerized substrate. On the other hand, an internal reformer that forms a modified layer inside the first substrate along the boundary between the peripheral edge portion and the central portion to be removed, and a peripheral edge that removes the peripheral edge portion from the modified layer as a base point. A substrate processing system, which has a removal device.
A substrate processing method for processing a substrate, in which a first substrate from which the outer peripheral portion of the surface film is removed within 400 nm from the surface in the thickness direction of the surface film and a second substrate are bonded to a polymerized substrate. On the other hand, an internal reforming step of forming a modified layer inside the first substrate along the boundary between the peripheral edge portion and the central portion to be removed, and a peripheral edge for removing the peripheral edge portion from the modified layer as a base point. A substrate processing method, which comprises, has, and has a removal step.

A substrate processing system that processes a substrate, the outer periphery of the first surface film formed on the surface of the first substrate before being bonded to the second surface film formed on the surface of the second substrate. A substrate processing system having a surface modification device for modifying a part.

Further, for example, the wafer processing system 1 may be provided with at least a joining device 40, and the other system may be provided with an internal reforming device 41, a surface reforming device 42, and a hydrophobizing device 43.

In such a case, in the wafer processing system 1, the surface modification treatment of the wafer W to be processed 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 carried into the wafer processing system 1 and then carried into the wafer processing system 1. The polymerized wafer T is formed in the joining device 40.

In other words, this example is as follows.
A substrate processing method for processing a substrate, the step of preparing a first substrate in which the outer peripheral portion of the first surface film is modified by the surface modification step, and the step of preparing the first substrate.
A joining step of joining the first surface film of the first substrate prepared in the step of preparing the first substrate and the second surface film formed on the surface of the second substrate. A substrate processing method.

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

In the wafer processing system 200 of the first embodiment, the wafer processing system 200 is provided with a peripheral edge removing device 210 in place of the internal reforming device 41 and a hydrophilization device 220 in place of the hydrophobicization device 43. have.

The peripheral edge removing device 210 removes the peripheral edge portion We of the wafer W to be processed (edge trimming) by using a grinding tool (not shown) such as a blade. At this time, the peripheral edge portion We may be completely removed from the front surface Wa to the back surface Wb, but in the present embodiment, since the back surface Wb is subsequently ground, only the surface layer is removed from the front surface Wa.

The hydrophilization device 220 immerses the polymerized wafer T in pure water to bond, for example, an OH group to the surfaces of the oxide films Fw and Fs in the unbonded region Ae. Specifically, it becomes hydrophilic by binding an OH group to a dangling bond formed on the surfaces of the oxide films Fw and Fs in the unbonded region Ae. In the present embodiment, the polymerized wafer T is immersed in pure water, but the method of imparting an OH group is not limited to this, 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 atmosphere.

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

First, the wafer transfer device 22 takes out the wafer W to be processed in the cassette Cw and transfers it to the transition device 34. Subsequently, the wafer transfer device 32 takes out the wafer W to be processed of the transition device 34 and transfers it to the peripheral edge removing device 210. As shown in FIG. 17A, the peripheral edge removing device 210 removes the surface layer of the peripheral edge portion We of the wafer W to be processed (step Q1 in FIG. 16). At this time, the width L3 (trim width) of the peripheral edge portion We is about 2 mm. Further, the surface layer of the peripheral portion We is removed, and the device layer D and the oxide film Fw in the peripheral portion We are also removed.

Next, the wafer W to be processed is transferred to the surface reforming device 42 by the wafer transfer device 32. In the surface reforming apparatus 42, the etching solution E is supplied to the outer peripheral portion Fwe of the oxide film Fw of the wafer W to be processed, and the surface layer of the outer peripheral portion Fwe is removed as shown in FIG. 17 (b) (step 16 in FIG. 16). Q2). At this time, the outer peripheral portion Fwe is removed inward from the inner end portion of the peripheral portion Wee, and the width of the outer peripheral portion Fwe is about 0.5 mm.

In parallel with steps Q1 and Q2, the support wafer S in the cassette Cs is taken out by the wafer transfer device 22, and is transferred to the joining device 40 by the wafer transfer device 32 via the transition device 34.

Next, the wafer W to be processed is transferred to the joining device 40 by the wafer transfer device 32. In the joining device 40, as shown in FIG. 17C, the oxide film Fw of the wafer W to be processed and the oxide film Fs of the support wafer S are joined to form the polymerized wafer T (step Q3 in FIG. 16). At this time, the oxide films Fw and Fs are not bonded at the outer peripheral portion Fwe, and the bonded region Ac and the unbonded region Ae are formed at the interface between the oxide films Fw and Fs. Then, the unbonded region Ae reduces the space where the high-pressure atmosphere at the end of the bonding wave is released, and the pressure is not reduced to the atmospheric pressure. By suppressing the sudden depressurization in this way, the edge void can be suppressed.

Next, the wafer W to be processed is transferred to the hydrophilization device 220 by the wafer transfer device 32. In the hydrophilization apparatus 220, the polymerized wafer T is immersed in pure water to bond OH groups to the surfaces of the oxide films Fw and Fs in the unbonded region Ae as shown in FIG. 17 (d) (step Q4 in FIG. 16). ). By hydrophilizing the surfaces of the oxide films Fw and Fs in the unbonded region Ae in this way, the oxide films Fw and Fs are hydrogen-bonded and adhere to each other. Then, the oxide films Fw and Fs are joined on the entire surface. At this time, further annealing treatment may be performed. In addition, for example, when the oxide films Fw and Fs are bonded in step Q3 and then the oxide films Fw and Fs in the unbonded region Ae are naturally bonded by water vapor in the atmosphere, step Q4 is unnecessary and omitted. be able to.

Next, the polymerized wafer T is transferred to the processing device 50 by the wafer transfer device 32. In the processing apparatus 50, the same processing as in the first embodiment is performed. 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).

After that, the polymerized wafer T that has been subjected to all the processing is conveyed to the transition device 34 by the wafer transfer device 32, and further transferred to the cassette Ct of the cassette mounting table 10 by the wafer transfer device 22. In this way, a series of wafer processing in the wafer processing system 1 is completed.

In the second embodiment as described above, the same effects as those in the first embodiment can be enjoyed. That is, 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 bonded in step Q3, an unbonded region Ae is formed at the interface between the oxide films Fw and Fs. To. The unbonded region Ae can suppress abrupt depressurization of the atmosphere at the end of the bonding wave, and as a result, can suppress edge voids.

Further, since the OH group is bonded to the surface of the oxide films Fw and Fs in the unbonded region Ae to make them hydrophilic in step Q4, the oxide films Fw and Fs can be adhered (bonded). Since the oxide films Fw and Fs can be bonded on the entire surface, the effective region of the wafer W to be processed can be increased.

Further, in the present embodiment, the effective region of the wafer W to be processed can be increased by suppressing the edge voids and bringing the oxide films Fw and Fs of the unbonded region Ae into close contact with each other. Specifically, in the conventional case shown in FIG. 1, the distance L1 from the end portion of the wafer W to be processed before processing to the edge void V is about 7 mm, and the effective region is a region of φ286 mm. On the other hand, in the present embodiment shown in FIG. 17, the distance L3 between the end of the wafer W to be processed before the processing in step Q1 and the end of the wafer W to be processed after the processing in step Q5 is about 2 mm. There is an effective area of φ296 mm. As described above, in the present embodiment, the effective area of the wafer W to be processed can be increased as compared with the conventional case, and a large number of chips as products can be manufactured.

In this embodiment, after the oxide film Fw and Fs activation treatment, hydrophilization treatment, bonding treatment and annealing treatment are sequentially performed in step Q3, the surface of the oxide film Fw and Fs in the unbonded region Ae is performed in step Q4. Was hydrophilized. In this respect, step Q4 may be performed between the hydrophilization treatment and the bonding treatment in step Q3, or may be performed between the bonding treatment and the annealing treatment. In such a case, the annealing process in step Q4 can be omitted.

Further, the wafer processing system 1 of the present embodiment includes a joining device 40, a surface modifying device 42, a processing device 50, a peripheral edge removing device 210, and a hydrophilization device 220, but the device configuration thereof is arbitrary. For example, the joining device 40, the surface modifying device 42, the peripheral edge removing device 210, and the hydrophilization device 220 may be provided in one system, and the processing device 50 may be provided in another system.

In the above-mentioned first embodiment and the second embodiment, the surface reforming apparatus 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 Fw is this. Not limited. For example, as shown in FIG. 18, the surface reformer 230 has a chuck 231 that holds the wafer W to be processed with the oxide film Fw facing upward. The chuck 231 is configured to be rotatable around a vertical axis by a rotation mechanism 232. Above the chuck 231, a polishing member 233 for being pressed by the outer peripheral portion Fw and removing the oxide film Fw is provided. The polishing member 233 is configured to be movable in the Z-axis direction by a moving mechanism (not shown).

By removing the outer peripheral portion Fwe using the polishing member 233 in this way, a damaged layer is formed on the surface of the oxide film Fw, so that the generation of edge void V is suppressed and at the same time, the unbonded region Ae is appropriately formed. Re-adhesion can be suppressed.

Further, since the surface particle size of the polishing member 233, that is, the abrasive particle size of the polishing member 233 can be arbitrarily selected, the film removal rate of the oxide film Fw and the surface roughness of the oxide film Fw after the film removal can be arbitrarily selected. Can be adjusted to. As a result, it is possible to more appropriately suppress the generation of edge void V and the re-adhesion of the unjoined region Ae.

In removing the oxide film Fw, for example, by using a polishing member 233 having an abrasive particle size larger than the thickness of the oxide film Fw, as shown in FIG. The outer peripheral portion Fwe may be removed so that the inclination is formed toward the direction, that is, the thickness of the oxide film Fw becomes smaller toward the outside in the radial direction in the side view.

When the slope is formed on the outer peripheral portion Fwe in this way, as shown in FIG. 19B, an unbonded region Ae is formed at the interface between the oxide films Fw and Fs so that the space gradually expands toward the outer peripheral direction. Will be done. As a result, at the time of bonding, the high-pressure atmosphere at the end of the bonding wave is gradually decompressed to the atmospheric pressure toward the outer peripheral direction, that is, sudden decompression can be suppressed, so that the edge void is appropriately applied. V can be suppressed.

As described above, in the surface reforming apparatus, it is preferable to remove the surface of the outer peripheral portion Fwe so that an inclination is formed toward the radial outer side of the wafer W to be processed. In the above description, the inclination is formed by the difference between the abrasive grain size of the polishing member 233 and the thickness of the oxide film Fw, but for example, the polishing member having a shape capable of forming the inclination in advance may be pressed. However, the inclination may be formed by devising, for example, the pressing direction of the polishing member 233. Further, such formation of the inclination on the outer peripheral portion Fwe may be performed in the surface modifying device 42, that is, when the outer peripheral portion Fwe of the oxide film Fw is removed by wet etching. In such a case, for example, by controlling the supply angle of the etching solution and controlling the supply amount of the etching solution, an inclination is formed toward the outer peripheral direction.

When the outer peripheral portion Fwe of the oxide film Fw is removed by using the polishing member 233 as described above, the removal debris of the oxide film Fw (hereinafter referred to as “debris”) is generated. Since the debris may cause poor bonding between wafers and defects in the product device, it is necessary to prevent the debris from adhering to the surface of the wafer W to be processed, particularly the surface of the device layer D.

Therefore, in order to prevent the debris from adhering to the wafer W to be processed, the surface reformer 230 that removes the oxide film Fw by using the polishing member 233 is provided with debris as shown in FIG. 20 (a). It is desirable that a fluid nozzle 244 for diffusing is provided. The fluid nozzle 244 is provided, for example, above the peripheral edge portion We of the wafer W to be processed. Further, for example, pure water, air, or the like is supplied from the fluid nozzle 244, and debris generated from the polished surface can be diffused outward in the outer peripheral direction. As a result, it is possible to prevent debris generated by polishing from scattering inward in the radial direction of the wafer W to be processed and adhering to the surface of the wafer W to be processed. 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 surface side of the wafer W to be processed, in order to more reliably disperse the generated debris to the outside in the outer peripheral direction. ..

The configuration of the surface reformer 230 may be any configuration as long as it can disperse the generated debris in the outer peripheral direction, and is not limited to the configuration described above. For example, as shown in FIG. 20 (b), the inside of the wafer W to be processed is positive pressure (“+” in FIG. 20 (b)) and the outside is negative pressure (“−” in FIG. 20 (b)). The pressure inside the surface reformer 230 may be controlled so as to be. As a result, in the surface reforming apparatus 230, an air flow is formed from the inside to the outside in the radial direction of the wafer W to be processed, and the generated debris can be appropriately scattered in the outer peripheral direction. Further, in such a case, by providing a suction mechanism 245 such as a vacuum pump on the outer side in the outer peripheral direction of the outer peripheral portion Fwe to be polished, it is possible to more appropriately form an air flow from the inner side to the outer side in the radial direction. ..

When the outer peripheral portion Fwe of the oxide film Fw is removed by using the polishing member 233 having a large abrasive particle size as described above, trimming is performed in the subsequent formation of the modified layer M (step P4 in FIG. 9). It may not be possible to properly align the processing position with the boundary between the peripheral portion We and the central portion Wc. This is because, for example, as shown in FIG. 21A, the boundary between the peripheral portion We and the central portion Wc, that is, the inner peripheral side end portion of the peripheral portion We as a removal target, is provided by the polishing member 233 having a large abrasive grain size. This is due to the fact that the creases (hereinafter, may be simply referred to as “kiwa”) become coarse and the trimming processing position cannot be appropriately set in the radial direction.

On the other hand, when the present disclosed person removes the outer peripheral portion Fwe of the oxide film Fw by using the polishing member 234 having a small abrasive particle size, as shown in FIG. 21B, the edge portion of the peripheral portion We is processed. It was found that the accuracy is improved and the trimming processing position can be set appropriately in the radial direction.

Therefore, in removing the outer peripheral portion Fwe of the oxide film Fw by polishing, first, as shown in FIG. 22, polishing is performed using a polishing member 234 having a small abrasive grain size at the edge of the peripheral portion We, and then polishing is performed. The polishing region 234a of 1 is formed. In the first polishing region 234a, polishing is performed by a polishing member 234 having a small abrasive particle size, so that the processing accuracy in the inner peripheral side end portion of the first polishing region 234a, that is, the edge of the peripheral portion We is improved. do. Then, following this, the grinding region by the polishing member 234 is left on the edge of the peripheral portion We, that is, the position separated by a distance L from the inner peripheral side end portion of the first polishing region 234a to the outside of both diameters. In, polishing is performed by a polishing member 233 having a large abrasive grain size toward the edge of the wafer W to be processed to form a second polishing region 233a.

In addition, in order to appropriately form the unbonded region Ae in the first polishing region 234a and the second polishing region 233a and to suppress the re-adhesion in the unbonded region Ae, the surface of the oxide film Fw is used. It is preferable that the area of the second polished region 233a that has been roughened is large. That is, it is sufficient that the first polishing region 234a can secure the processing accuracy of the edge portion We required in the alignment process, and it is desirable that the distance L is small. Specifically, the alignment process can be appropriately performed by setting the distance L to be larger than the abrasive particle size of the polishing member 233 forming at least the second polishing region 233a.

As a result, the processing accuracy of the edge of the peripheral portion We is improved, so that the alignment in the formation of the modified layer M (step P4 in FIG. 9) can be appropriately performed, and the alignment is appropriately applied to the edge of the wafer W to be processed. A damage layer is formed on the surface of the oxide film Fw, and it is possible to suppress the generation of edge void V and at the same time appropriately suppress the re-adhesion of the unbonded region Ae. Further, since the abrasive particle size of the polishing member 233 can be arbitrarily selected, the film removal rate of the oxide film Fw and the surface roughness of the oxide film Fw after the film removal can be arbitrarily adjusted. As a result, it is possible to more appropriately suppress the generation of edge void V and the re-adhesion of the unjoined region Ae.

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

Further, even if the grinding of the peripheral portion We by the polishing member 234 having a small abrasive particle size is performed, for example, when the wafer W to be processed is inclined outward in the radial direction as shown in FIG. good.

In the above first embodiment and the second embodiment, the surface reforming apparatus 42 performs wet etching to remove the outer peripheral portion Fwe of the oxide film Fw, but this is the method for removing the outer peripheral portion Fwe. Not limited to. For example, the outer peripheral portion Fwe may be removed by irradiating the outer peripheral portion Fwe with a laser beam having a wavelength that does not pass through the oxide film Fw, for example, ultraviolet light.

Further, although the surface modifying device 42 removes the outer peripheral portion Fwe as a modification treatment of the outer peripheral portion Fwe of the oxide film Fw, the outer peripheral portion Fwe may be projected. In such a case, as shown in FIG. 23, the surface reformer 240 has a chuck 241 that holds the wafer W to be processed with the oxide film Fw facing upward. The chuck 241 is configured to be rotatable around a vertical axis by a rotation mechanism 242. Above the chuck 241 is provided a laser head 243 that irradiates the outer peripheral portion Fwe with the laser beam R. As the laser beam R, for example, ultraviolet light is used. Further, 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 reformer 240, as shown in FIG. 24A, the outer peripheral portion Fwe is projected by the laser beam R. Then, as shown in FIG. 24 (b), the oxide films Fw and Fs are not bonded at the outer peripheral portion Fwe. That is, when the oxide films Fw and Fs are bonded, an unbonded region Ae corresponding to the bonded region Ac to which the oxide films Fw and Fs are bonded and the outer peripheral portion Fwe is formed at the interface between the oxide films Fw and Fs. To.

In such a case, since the unbonded region Ae is formed in the present embodiment as in the case of removing the outer peripheral portion Fwe shown in FIG. 8, the space where the high-pressure atmosphere at the end of the bonding wave is released becomes small. , It is not decompressed to atmospheric pressure. By suppressing the sudden depressurization in this way, edge voids can be suppressed. Moreover, by forming the protrusion of the outer peripheral portion Fwe discontinuously in the circumferential direction, the high-pressure atmosphere at the end portion of the bonding wave can be released to the outside of the polymerized wafer T. Then, even if dew condensation occurs on the outer peripheral portion Fwe, water vapor can escape to the outside of the polymerized wafer T.

Further, in the surface reforming apparatus 240, the laser beam R is used when the outer peripheral portion Fwe is projected, and the top portion of the outer peripheral portion Fwe is roughened by the laser beam R, and the outer peripheral portion Fwe is roughened. In such a case, it is possible to further suppress the bonding of the oxide films Fw and Fs at the outer peripheral portion Fwe, that is, the unbonded region Ae can be formed more reliably. As a result, it is possible to suppress sudden depressurization and suppress edge voids.

The roughening of the outer peripheral portion Fwe may also be performed when the surface layer of the outer peripheral portion Fwe is removed by using the surface modifying device 42.

In the removal of the outer peripheral portion Fwe in the surface reforming device 240, that is, in the removal of the outer peripheral portion Fwe by the laser beam R, debris is generated in the same manner as the removal of the outer peripheral portion Fwe by the polishing member 233 in the surface reforming device 230. do.

The debris generated by the irradiation of the laser beam R tends to diffuse toward the open space side near the irradiation point of the laser beam R. That is, for example, when the laser beam R irradiates the oxide film Fw near the central portion of the wafer W to be processed, the debris diffuses in the entire circumferential direction around the irradiation point of the laser beam R. On the other hand, for example, when the laser beam R irradiates the oxide film Fw near the outer edge portion of the wafer W to be processed, the debris tends to diffuse to the outside in the outer peripheral direction of the wafer W to be processed, which is an open space.

In view of the above tendency, in the removal of the oxide film Fw by the laser beam R, the outer peripheral portion Fwe is divided into a plurality of regions with respect to the radial direction of the wafer W to be processed, and the plurality of regions are directed from the radial outside to the inside. It may be done in order. FIG. 25 shows the region distribution when the outer peripheral portion Fwe of the oxide film Fw is divided into, for example, two annular regions in the radial direction. As shown in FIG. 25, the outer peripheral portion Fwe is divided into annular regions Fwe1 and Fwe2 in order from the outside in the radial direction.

In 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 at the irradiation point Pt (1) is removed. .. At this time, as shown in FIG. 26A, the annular 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, so that the generated debris is the same. It is diffused into an open space.

When the oxide film Fw is removed at the irradiation point Pt (1), the wafer W to be processed is subsequently rotated, and the laser beam R is irradiated to the irradiation point Pt (2). The irradiation point Pt (2) is set adjacent to the irradiation point Pt (1). At this time, since the irradiation point Pt (2) is located in the annular region Fwe1 and also faces the irradiation point Pt (1) from which the oxide film Fw has already been removed, debris is caused in the radial direction of the wafer W to be processed. Diffusion inward is more reliably suppressed. By repeating the irradiation operation of the laser beam R and the rotation operation of the wafer W to be processed, the oxide film Fw is removed over the entire circumference of the annular region Fwe1.

When the removal of the oxide film Fw of the annular region Fwe1 is completed, the laser head 243 subsequently moves above the annular region Fwe2, and the removal of the oxide film Fw of the annular region Fwe2 is started. At this time, since the removal of the oxide film Fw of the annular region Fwe1 has already been completed, as shown in FIG. 26B, the annular region Fwe2 faces the open space outside the outer peripheral direction of the wafer W to be processed. , The generated debris is diffused into the open space. Then, the irradiation operation of the series of laser beams R and the rotation operation of the wafer W to be processed are repeatedly performed in the annular region Fwe2 as well, and the oxide film Fw is removed over the entire circumference of the annular region Fwe2.

According to the above operation, since the irradiation point of the laser beam R always faces the open space outside the outer peripheral direction of the wafer W to be processed, it is possible to suppress the diffusion of debris in the radial direction of the wafer W to be processed. It is possible to appropriately suppress adhesion to the wafer W to be processed. Further, according to the above operation, the direction of debris scattering can be directed to the outer peripheral direction of the wafer W to be processed and to the irradiation point direction of the previous laser beam R, so that the debris is further adhered to the wafer W to be processed. It can be appropriately suppressed, and the configuration of the exhaust equipment in the surface reforming device 240 can be simplified.

In order to more appropriately prevent debris generated by irradiation with laser light from adhering to the wafer W to be processed, the surface reforming device 240 is provided with, for example, a fluid nozzle or the like, similarly to the surface reforming device 230. You may. Further, as a matter of course, the internal pressure of the surface reforming apparatus 240 may be controlled to generate an air flow from the radial inside to the outside of the wafer W to be processed, or a suction mechanism may be provided. May be good.

Furthermore, the depth of the irradiation point of the laser beam in the annular region Fwe2 may be controlled to be shallower than the depth of the irradiation point of the laser beam in the annular region Fwe1. That is, as shown in FIG. 27, the irradiation point depth of the laser beam R may be changed so that the removal thickness of the oxide film Fw gradually increases toward the radial outer side of the wafer W to be processed. As a result, the surface of the outer peripheral portion Fwe is removed so as to have a substantially inclined surface, so that the same effect as that of the outer peripheral portion Fwe having the above-mentioned inclination can be enjoyed, and the generation of edge void V and the re-joining region Ae can be enjoyed. Adhesion can be appropriately suppressed. At this time, it is desirable that the difference H2 in the removed thickness in each annular region is within 400 nm.

In the above description, the case where the outer peripheral portion Fwe is divided into two in the radial direction has been described as an example, but the number of divisions of the outer peripheral portion Fwe is not limited to this, and the surface of the oxide film Fw can be divided by any number of divisions. Can be removed. At this time, by increasing the number of divisions, the resolution of the substantially inclination can be improved, and the effect of suppressing the generation of edge void V and the re-adhesion of the unjoined region Ae can be more appropriately enjoyed.

In the above embodiment, 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, has been described, but the surface film is not limited to this. For example, a SiC film, a SiCN film, or the like may be formed. Further, the second embodiment can 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 the above embodiment, the unbonded region Ae is formed by removing the oxide film Fw in the outer peripheral portion Fwe, but the method for forming the unbonded region Ae is not limited to this.

As described above, the oxide film Fw of the wafer W to be treated and the oxide film Fs of the support wafer S are hydrophilized by imparting OH groups to the dangling bonds formed on the surfaces of the oxide films Fw and Fs, and the oxide film Fw is formed. And the oxide film Fs are bonded by hydrogen bonds.

Therefore, in the surface reforming apparatus 330 included in the wafer processing system according to the third embodiment, the unbonded region Ae is formed by supplying the hydrophobic material to the oxide film Fw of the wafer W to be bonded before bonding. Form. Specifically, in the surface reforming apparatus 330, by supplying the silylating material G to the outer peripheral portion Fwe of the oxide film Fw, the outer peripheral portion Fw is made hydrophobic and water repellent.

Hereinafter, the surface modifying apparatus 330 according to the third embodiment will be described with reference to the drawings. FIG. 28 is a side view schematically showing an outline of the configuration of the surface reforming apparatus 330. FIG. 29 is a flowchart showing a main process of wafer processing in the wafer processing system according to the third embodiment. Further, FIG. 30 is an explanatory diagram showing a state of wafer processing in the third embodiment. In the present embodiment, the elements having substantially the same functional configuration as those of the first and second embodiments described above are designated by the same reference numerals, so that duplicate description will be omitted.

As shown in FIG. 28, the surface reformer 330 has a chuck 350 that holds the wafer W to be processed with the oxide film Fw facing upward. The chuck 350 is configured to be rotatable around a vertical axis by a rotation mechanism 351. Above the chuck 350, a nozzle 352 for applying the silylated material G to the outer peripheral portion of the oxide film Fw is provided. The nozzle 352 communicates with a silylating material supply source (not shown) that stores and supplies the silylating material G. Further, 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 according to 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 transition device 34. Subsequently, the wafer transfer device 32 takes out the wafer W to be processed of the transition device 34 and transfers it to the surface reforming device 330. In the surface modifier 330, a silyl group (Si—R) is formed on the dangling bond formed on the outer peripheral portion Fwe of the oxide film Fw by the silylating material G before the bonding is performed (before step U2 in FIG. 29). Is given (step U1 in FIG. 29). As a result, as shown in FIG. 30A, 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 peripheral portion Fwe is subsequently transferred to the joining device 40 by the wafer transfer device 32. In the joining device 40, the oxide film Fw is activated and hydrophilized prior to joining. A silyl group is added to the outer peripheral portion Fwe in step U1. As a result, in the hydrophilization treatment in the joining device 40, the outer peripheral portion Fwe is not hydrophilized. Specifically, the hydrophilization treatment is performed by imparting an OH group to the dangling bond formed on the oxide film Fw as described above. Here, since the silyl group is already imparted to the outer peripheral portion Fwe to make it hydrophobic and water repellent, it is prevented that the OH group is imparted to the outer peripheral portion Fwe.

When the oxide film Fw is activated and hydrophilized, the oxide film Fw of the wafer W to be treated and the support wafer S previously activated and hydrophilized are subsequently oxidized as shown in FIG. 30 (b). The films Fs are bonded to form a laminated wafer T (step U2 in FIG. 29). At this time, the oxide films Fw and Fs are not bonded at the outer peripheral portion Fwe, and the bonded region Ac and the unbonded region Ae are formed at the interface between the oxide films Fw and Fs.

Next, the polymerized wafer T is transferred to the internal reformer 41 by the wafer transfer device 32. The internal reformer 41 irradiates the inside of the wafer W to be processed with laser light from the laser head while rotating the wafer W to be processed. Then, as shown in FIG. 30 (c), an annular peripheral edge modification layer M1 is formed inside the wafer W to be processed along the boundary between the peripheral edge portion We and the central portion Wc of the wafer to be processed W (FIG. 29). Step U3). Further, the laser head is moved to form the split reforming layer M2 extending in the radial direction of the wafer W to be processed on the radial outer side of the peripheral modification layer M1.

Next, the polymerized wafer T is conveyed by the transfer unit 70 to the processing apparatus 50 via 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 edge portion We is removed as shown in FIG. 30 (d) (step U4 in FIG. 29).

After that, the polymerized wafer T that has been subjected to all the processing is conveyed to the transition device 34 by the wafer transfer device 32, and further transferred to the cassette Ct of the cassette mounting table 10 by the wafer transfer device 22. In this way, a series of wafer processing in the wafer processing system 1 is completed.

According to the series of wafer treatments according to the present embodiment, unlike the first and second embodiments, the oxide film Fw is not removed or the surface is not roughened in the unbonded region Ae. That is, the high-pressure atmosphere at the end of the bonding wave B according to the present embodiment is released at the end of the wafer W to be processed, and an edge void V is generated as shown in FIG. 30 (b). However, since the oxide film Fw is not removed or the surface is not roughened as described above, the position where the edge void V is generated is on the end side of the wafer W to be processed, that is, the outer periphery of the peripheral edge portion We as the removal target. It is formed in the part Fwe. As a result, even if edge voids are generated, the outer peripheral portion Fwe is not a device forming portion, so that the manufacturing process of the semiconductor device is not substantially affected.

The silylation of the outer peripheral portion Fwe of the oxide film Fw can be performed at any timing as long as it is before the bonding of the wafer W to be processed. That is, in the above embodiment, the silylation treatment was performed before the bonding and before the activation of the oxide film Fw, but for example, it may be performed between the activation treatment and the hydrophilization treatment. It may be performed after the hydrophilization treatment. In any case, the unbonded region Ae can be appropriately formed by silylating the outer peripheral portion Fwe before the hydrogen bond between the oxide film Fw and the oxide film Fs in the bonding step.

Further, according to the above embodiment, the unbonded region Ae was formed by silylating the outer peripheral portion Fwe of the oxide film Fw, but if the outer peripheral portion Fw can be made hydrophobic and water repellent, it can be formed. The method for hydrophobizing the outer peripheral portion Fwe is not limited to this. For example, by imparting a methyl group to the dangling bond as described above, the outer peripheral portion Fwe may be hydrophobized. Further, for example, a mold release agent may be supplied to the outer peripheral portion Fwe of the oxide film Fw.

According to the first to third embodiments described above, the thinning of the wafer W to be processed was performed by grinding the back surface Wb in the processing apparatus, but the thinning method of the wafer W to be processed is limited to this. I can't. For example, as shown in FIG. 31A, the peripheral surface modification layer M1 and the internal surface modification layer M3 are formed inside the wafer W to be processed along the surface direction of the wafer W to be processed. The order of formation of the peripheral modification layer M1 and the inner surface modification layer M3 can be arbitrarily determined. Then, as shown in FIG. 31B, the edge trim of the wafer to be processed W starting from the peripheral modification layer M1 and the back surface Wb side of the wafer W to be processed starting from the internal surface modification layer M3. Perform separation. In this way, the wafer W to be processed can be thinned by separating the back surface Wb side with the internal surface modification layer M3 as a base point.

As described above, in the wafer processing according to the present embodiment, since the unbonded region Ae is formed on the outer peripheral portion Fwe, the re-adhesion of the outer peripheral portion Fwe is suppressed, and the peripheral portion We is appropriately peeled off. It can be carried out. Further, by thinning the wafer W to be processed by separating from the internal surface reforming layer M3 as a base point in this way, it is necessary to grind the back surface Wb and the end face for thinning and edge trim as in the conventional case. There is no. That is, when the wafer W to be processed is thinned and the edge trim is performed, grinding debris is not generated, and it is not necessary to provide a grinding tool which is a consumable item, so that the apparatus configuration can be simplified.

Further, when the wafer W to be processed is thinned by forming the internal surface modification layer M3 in this way, the thinning of the wafer W to be processed and the edge trimming may be performed at the same time. Specifically, the upper end of the peripheral modification layer M1 formed as shown in FIG. 32A is substantially aligned with the height at which the internal surface modification layer M3 is formed. Then, in such a state, the back surface Wb side of the wafer W to be processed is separated from the peripheral surface modified layer M1 and the internal surface modified layer M3 as a base point, so that the peripheral surface portion We is the back surface as shown in FIG. 32 (b). It is removed together with the wafer on the Wb side.

Also in this edge trimming method, as described above, in the wafer processing according to the present embodiment, since the unbonded region Ae is formed in the outer peripheral portion Fwe, re-adhesion of the outer peripheral portion Fwe is suppressed, which is appropriate. The peripheral portion We can be peeled off. Further, in the past, grinding for thinning the wafer W to be processed and grinding for edge trim were performed, respectively, whereas thinning of the wafer W to be processed and edge trim can be performed at the same time. Further, as described above, by thinning the wafer W to be processed by separation using the internal surface modification layer M3 as a base point, the back surface Wb and the end face are ground for thinning and edge trimming as in the conventional case. There is no need. That is, when the wafer W to be processed is thinned and the edge trim is performed, grinding debris is not generated, and it is not necessary to provide a grinding tool which is a consumable item, so that the apparatus configuration can be simplified.

The embodiments disclosed this time should be considered to be exemplary and not restrictive in all respects. The above embodiments may be omitted, replaced or modified in various embodiments without departing from the scope of the appended claims and their gist.

1,200 Wafer processing system 40 Joining device 42 Surface reforming device Fs, Fw Oxidation film S Supporting wafer T Polymerized wafer W Processed wafer

Claims (20)

It is a board processing system that processes boards.
It has a surface modification device that modifies the outer peripheral portion of the first surface film formed on the surface of the first substrate before being bonded to the second surface film formed on the surface of the second substrate. death,
The surface modification device is a substrate processing system that roughens the outer peripheral portion of the first surface film toward the outer side in the radial direction so that the surface roughness of the first surface film becomes large . It has a joining device for joining the first surface film of the first substrate whose outer peripheral portion has been modified by the surface modifying device and the second surface film formed on the surface of the second substrate. , The substrate processing system according to claim 1. The substrate processing system according to claim 1 or 2, wherein the surface modification device removes an outer peripheral portion of the first surface film. The substrate processing system according to claim 3, wherein the surface modification device removes within 400 nm from the surface in the thickness direction of the first surface film. The surface modifying apparatus according to claim 3 or 4, wherein the outer peripheral portion of the first surface film is removed radially outward in a side view so that the thickness of the first surface film becomes smaller. The substrate processing system described. The outer peripheral portion of the first surface film is divided into a plurality of annular regions in the radial direction.
Claims 3 to 3, wherein the removal of the outer peripheral portion of the first surface film in the surface modifying apparatus is sequentially performed from the annular region located on the outer side in the radial direction toward the annular region located on the inner side in the radial direction. 5. The substrate processing system according to any one of 5. The substrate processing system according to any one of claims 3 to 6, wherein an air flow is formed inside the surface modifier from the radial inside to the radial outside of the first surface film. .. At the interface between the first surface film and the second surface film bonded to each other, the bonded region to which the first surface film and the second surface film are bonded is removed by the surface modifying device. An unbonded region corresponding to the first surface film formed is formed.
The substrate processing system according to any one of claims 3 to 7, wherein the substrate processing system includes a hydrophilization device for hydrophilizing the first surface film and the second surface film in the unbonded region. .. The substrate processing system according to claim 8, further comprising a peripheral edge removing device for removing the peripheral edge portion of the first substrate before modifying the peripheral edge portion of the first surface film with the surface modifying device. The substrate processing system according to claim 1, wherein the surface modification device projects an outer peripheral portion of the first surface film. It is a substrate processing method that processes a substrate.
It involves modifying the outer periphery of the first surface film formed on the surface of the first substrate before being bonded to the second surface film formed on the surface of the second substrate.
In the modification of the outer peripheral portion of the first surface film, the outer peripheral portion of the first surface film is roughened so that the surface roughness of the first surface film becomes larger toward the outer side in the radial direction. Substrate processing method . 11. The aspect of claim 11 , wherein the first surface film of the first substrate whose outer peripheral portion has been modified is joined to a second surface film formed on the surface of the second substrate. Substrate processing method. The substrate processing method according to claim 11 or 12 , wherein the outer peripheral portion of the first surface film is removed in the modification of the outer peripheral portion of the first surface film. The substrate processing method according to claim 13 , wherein in the modification of the outer peripheral portion of the first surface film, the area within 400 nm from the surface in the thickness direction of the first surface film is removed. In the modification of the outer peripheral portion of the first surface film, the outer peripheral portion of the first surface film is removed so as to reduce the thickness of the first surface film toward the radial outer side in the side view. The substrate processing method according to claim 13 or 14 . The outer peripheral portion of the first surface film is divided into a plurality of annular regions in the radial direction.
One of claims 13 to 15 , wherein the removal of the outer peripheral portion of the first surface film is sequentially performed from the annular region located on the outer side in the radial direction toward the annular region located on the inner side in the radial direction. The substrate processing method described in 1. In any one of claims 13 to 16 , in the modification of the outer peripheral portion of the first surface film, an air flow is formed from the radial inside to the radial outside of the first surface film. The substrate processing method described. At the interface between the first surface film and the second surface film bonded to each other, a bonding region to which the first surface film and the second surface film are bonded and the first surface film are formed. An unbonded region corresponding to the first surface film whose outer peripheral portion was removed by modification was formed.
The substrate treatment method according to any one of claims 13 to 17 , wherein the substrate treatment method comprises hydrophilizing the first surface film and the second surface film in the unbonded region. The substrate processing method according to claim 18 , which comprises removing the peripheral edge portion of the first substrate before modifying the outer peripheral portion of the first surface film. The substrate processing method according to claim 11 or 12 , wherein the outer peripheral portion of the first surface film is projected in the modification of the outer peripheral portion of the first surface film.

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