JP7291809B2 - SUBSTRATE PROCESSING APPARATUS AND SUBSTRATE PROCESSING METHOD - Google Patents

Description

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

In Patent Document 1, in a grinding apparatus equipped with a cleaning roller for cleaning a workpiece after grinding, depending on the relative position between a suction pad that adsorbs and holds and conveys the workpiece and the cleaning roller, It is disclosed to change the direction of rotation of the cleaning roller. The cleaning roller is arranged on the carry-out path of the workpiece by the suction pad.

Japanese Patent Application Laid-Open No. 2005-302831

The technology according to the present disclosure appropriately cleans the substrate before or after the grinding process.

One aspect of the present disclosure is a substrate processing apparatus that processes a substrate, and includes a substrate transport mechanism that holds and transports one surface of the substrate; , a cleaning mechanism for cleaning the other surface of the substrate, the cleaning mechanism being rotatable by a driving mechanism, a water-absorbing roller having a water-absorbing layer on at least a surface layer of the peripheral surface; and the water-absorbing roller. a cleaning liquid nozzle that supplies cleaning liquid to the roller; and a squeeze roller that is provided downstream of the cleaning liquid nozzle in the direction of rotation of the water absorbing roller and is movable in a contacting/separating direction with respect to the water absorbing roller. and cleaning the other surface of the substrate by bringing the water absorbing roller into contact with the other surface of the substrate.

According to the present disclosure, it is possible to properly clean the substrate before or after the grinding process.

FIG. 4 is a side view showing a configuration example of a superposed wafer; 1 is a plan view showing an outline of the configuration of a wafer processing system according to this embodiment; FIG. FIG. 2 is a flow chart showing main steps of wafer processing; It is a sectional view showing an example of composition of a back surface cleaning device concerning this embodiment. It is a top view which shows the structural example of the back surface cleaning apparatus which concerns on this embodiment. FIG. 4 is a flow chart showing main steps of back surface cleaning according to the present embodiment. FIG. 4 is an explanatory diagram showing main steps of back surface cleaning according to the present embodiment; FIG. 4 is an explanatory diagram showing main steps of back surface cleaning according to the present embodiment; It is a cross-sectional view showing a configuration example of a back surface cleaning apparatus according to another embodiment.

In a manufacturing process of a semiconductor device, a substrate having a plurality of devices such as electronic circuits formed on its surface (hereinafter referred to as a "first wafer") is ground on the back surface of the first wafer to form a first wafer. 1 wafer thinning has been performed. If the thinned first wafer is transported as it is or subjected to subsequent processing, the first wafer may be warped or cracked. Therefore, in order to reinforce the first wafer, for example, the first wafer is attached to a supporting substrate (hereinafter referred to as "second wafer") to form a superposed substrate (hereinafter referred to as "superposed wafer"). is being done.

When grinding the back surface of the first wafer described above, a grinding wheel is usually brought into contact with the back surface of the first wafer while the back surface of the second wafer is held by a chuck. However, when the back surface of the first wafer is ground in this manner, grinding debris generated by grinding and cleaning liquid supplied toward the first wafer during grinding may enter the back surface side of the second wafer. may adhere to the surface. When the grinding dust and the cleaning liquid adhere to the wafer, the grinding dust and the cleaning liquid adhering to the back surface of the second wafer may scatter and drip during transfer of the superposed wafer, contaminating the inside of the module.

The grinding apparatus described in the above-mentioned Patent Document 1 is an apparatus equipped with cleaning means for cleaning the back surface of the second wafer (workpiece) after grinding in order to suppress the scattering of such grinding dust. be. However, in this grinding apparatus, the cleaning liquid is supplied to the cleaning roller that abuts on the back surface of the second wafer, so that the cleaning roller is brought into contact with the back surface of the second wafer while absorbing the cleaning liquid. 2, the back surface of the wafer could not be properly cleaned. Specifically, since the cleaning roller absorbs the cleaning liquid, when the cleaning roller is used to clean the back surface of the second wafer, the cleaning liquid may remain on the back surface of the second wafer. was there. If the attached cleaning liquid does not completely absorb water and remains on the rear surface of the second wafer, the remaining cleaning liquid may scatter and drip into the module, causing contamination.

The technology according to the present disclosure appropriately cleans the substrate before or after the grinding process. Specifically, when cleaning the substrate before or after the grinding process, the remaining cleaning liquid on the substrate after cleaning is appropriately suppressed. A wafer processing system as a substrate processing apparatus and a wafer processing method as a substrate processing method according to the present embodiment will be described below with reference to the drawings. In the present specification and drawings, elements having substantially the same functional configuration are denoted by the same reference numerals, thereby omitting redundant description.

In the later-described wafer processing system 1 according to the present embodiment, as shown in FIG. , the superposed wafer T is processed. Then, in the wafer processing system 1, the back surface Wb of the first wafer W is ground to be thinned. Hereinafter, the surface of the first wafer W that is bonded to the second wafer S is referred to as a front surface Wa, and the ground surface opposite to the front surface Wa is referred to as a back surface Wb as one surface. Similarly, in the second wafer S, the surface on the side bonded to the first wafer W is called a surface Sa, and the surface opposite to the surface Sa is called a back surface Sb as another surface.

The first wafer W is, for example, a semiconductor wafer such as a silicon substrate, and a device layer D including a plurality of devices is formed on the surface Wa. A surface film Fw is further formed on the device layer D, and is bonded to the surface film Fs of the second wafer S via the surface film Fw. Examples of the surface film Fw include oxide films (SiO ₂ film, TEOS film), SiC films, SiCN films, adhesives, and the like. The peripheral edge portion We of the first wafer W is chamfered, and the thickness of the cross section of the peripheral edge portion We decreases toward its tip.

The second wafer S is a wafer that supports the first wafer W, for example. A surface film Fs is formed on the surface Sa of the second wafer S, and the peripheral portion is chamfered. Examples of the surface film Fs include oxide films (SiO ₂ film, TEOS film), SiC films, SiCN films, adhesives, and the like. Also, the second wafer S functions as a protective material (support wafer) that protects the device layer D of the first wafer W. As shown in FIG. The second wafer S does not need to be a support wafer, and may be a device wafer on which a device layer is formed as with the first wafer W. In such a case, the surface film Fs is formed on the surface Sa of the second wafer S with the device layer interposed therebetween.

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

As shown in FIG. 2, the wafer processing system 1 has a configuration in which a loading/unloading station 2 and a processing station 3 are integrally connected. For example, the loading/unloading station 2 loads/unloads a cassette Ct capable of accommodating a plurality of superposed wafers T to/from the outside. The processing station 3 includes various processing devices for performing predetermined processing on the superposed wafer T. FIG.

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

The loading/unloading station 2 is provided with a wafer transfer device 20 adjacent to the cassette mounting table 10 on the X-axis negative direction side of the cassette mounting table 10 . The wafer transfer device 20 is configured to be movable on a transfer path 21 extending in the Y-axis direction. The wafer transfer device 20 also has, for example, two transfer arms 22, 22 that hold and transfer the superposed wafer T. As shown in FIG. Each transport arm 22 is configured to be movable in the horizontal direction, the vertical direction, and around the horizontal axis and around the vertical axis. Note that the configuration of the transport arm 22 is not limited to the present embodiment, and may take any configuration. The wafer transfer device 20 is configured to transfer the overlapped wafers T to the cassette Ct of the cassette mounting table 10 and the transition device 30, which will be described later.

The loading/unloading station 2 is provided with a transition device 30 for transferring the superimposed wafers T adjacent to the wafer transfer device 20 on the X-axis negative direction side of the wafer transfer device 20 .

The processing station 3 is provided with, for example, three processing blocks G1 to G3. The first processing block G1, the second processing block G2, and the third processing block G3 are arranged in this order from the X-axis positive direction side (carrying in/out station 2 side) to the negative direction side.

The first processing block G1 includes an etching device 40 for etching the ground surface of the first wafer W ground by a processing device 80 described later, a cleaning device 41 for cleaning the ground surface of the first wafer W, A wafer carrier 50 is provided. The etching device 40 and the cleaning device 41 are stacked and arranged. The number and arrangement of the etching device 40 and the cleaning device 41 are not limited to this. For example, the etching device 40 and the cleaning device 41 may be placed side by side in the X-axis direction. Furthermore, the etching device 40 and the cleaning device 41 may be stacked.

The wafer transfer device 50 is arranged, for example, on the Y-axis negative direction side of the etching device 40 and the cleaning device 41 . The wafer transfer device 50 has, for example, two transfer arms 51, 51 that hold and transfer the superposed wafer T. As shown in FIG. Each transport arm 51 is configured to be movable in the horizontal direction, the vertical direction, and around the horizontal axis and around the vertical axis. Note that the configuration of the transport arm 51 is not limited to the present embodiment, and may take any configuration. The wafer transfer device 50 is configured to transfer the overlapped wafer T to the transition device 30, the etching device 40, the cleaning device 41, and an alignment device 60, which will be described later.

The second processing block G2 is provided with an alignment device 60 for adjusting the horizontal orientation of the first wafer W before grinding, and a wafer transfer device 70 .

A wafer transfer device 70 as a substrate transfer mechanism is arranged, for example, on the Y-axis positive direction side of the alignment device 60 . The wafer transfer device 70 has, for example, two transfer arms 71, 71 that transfer the superposed wafer T while suctioning and holding it with a suction holding surface 71a. Each transport arm 71 is supported by a multi-joint arm member 72 and is configured to be movable in the horizontal direction, the vertical direction, and around the horizontal axis and around the vertical axis. Note that the configuration of the transport arm 71 is not limited to the present embodiment, and may take any configuration. The wafer transfer device 70 is configured to transfer the superposed wafer T to the etching device 40, the cleaning device 41, the alignment device 60, and the processing device 80, which will be described later.

A processing device 80 and a back surface cleaning device 90 are provided in the third processing block G3.

The processing device 80 has a rotary table 81 . Four chucks 82 for holding the superposed wafer T by suction are provided on the rotary table 81 . The four chucks 82 are movable to the transfer position A0 and the processing positions A1 to A3 by rotating the rotary table 81 around the rotation center line 83. As shown in FIG. Each of the four chucks 82 is configured to be rotatable about a vertical axis by a rotating mechanism (not shown).

At the transfer position A0, transfer of the superposed wafer T by the wafer transfer device 70 is performed. A rough grinding unit 84 is arranged at the processing position A1 to roughly grind the first wafer W. As shown in FIG. A medium grinding unit 85 is arranged at the processing position A2 to mediumly grind the first wafer W. As shown in FIG. A finish grinding unit 86 is arranged at the processing position A3, and the first wafer W is finish ground. At the delivery position A0, the back surface Wb of the first wafer W after the grinding process at the processing positions A1 to A3 is further cleaned.

The back surface cleaning device 90 as a cleaning mechanism is provided below the transfer path of the superposed wafers T by the wafer transfer device 70 in the third processing block G3, specifically, on the X-axis positive direction side of the delivery position A0. . The back surface cleaning device 90 cleans the back surface Sb of the second wafer S after the grinding process. A detailed configuration of the back surface cleaning device 90 will be described later.

The wafer processing system 1 described above is provided with a controller 100 . The control device 100 is, for example, a computer and has a program storage unit (not shown). The program storage unit stores programs for controlling the processing of the superposed wafers T in the wafer processing system 1 . The program storage unit also stores a program for controlling the operation of drive systems such as the various processing devices and transfer devices described above to realize wafer processing, which will be described later, in the wafer processing system 1 . The program may be recorded in a computer-readable storage medium H and installed in the control device 100 from the storage medium H.

Next, wafer processing performed using the wafer processing system 1 configured as described above will be described. In this embodiment, a superimposed wafer T in which the first wafer W and the second wafer S are bonded in advance in a bonding device (not shown) outside the wafer processing system 1 is formed.

First, a cassette Ct containing a plurality of superposed wafers T is mounted on the cassette mounting table 10 of the loading/unloading station 2 . Next, the superposed wafer T in the cassette Ct is taken out by the wafer transfer device 20 and transferred to the transition device 30 .

Subsequently, the wafer transfer device 50 takes out the superimposed wafer T from the transition device 30 and transfers it to the alignment device 60 . The alignment device 60 adjusts the horizontal position of the first wafer W (step S1 in FIG. 3).

The overlapped wafer T whose horizontal orientation has been adjusted is then transferred from the alignment device 60 to the processing device 80 by the wafer transfer device 70 .

The superposed wafer T transported to the processing device 80 is delivered to the chuck 82 at the delivery position A0. Subsequently, the rotary table 81 is rotated to sequentially move the chuck 82 to the processing positions A1 to A3.

At the processing position A1, the back surface Wb of the first wafer W is roughly ground by the rough grinding unit 84 (step S2 in FIG. 3).

At the processing position A2, the intermediate grinding unit 85 intermediately grinds the rear surface Wb of the first wafer W (step S3 in FIG. 3).

At the processing position A3, the back surface Wb of the first wafer W is finish ground by the finish grinding unit 86 (step S4 in FIG. 3).

After the first wafer W is thinned to a desired thickness by the grinding process, the chuck 82 is moved to the transfer position A0. Transfer of the superposed wafer T moved to the transfer position A0 to the cleaning device 41 by the wafer transfer device 70 is next started.

Below the transport path of the overlapped wafers T in the third processing block G3, more specifically, below the transport path of the overlapped wafers T from the transfer position A0 to the cleaning device 41, there is a second wafer S A back surface cleaning device 90 is provided for cleaning the back surface Sb of the .

In the wafer processing according to the present embodiment, the back surface Sb of the second wafer S of the superposed wafer T being transferred from the delivery position A0 to the cleaning device 41 by the wafer transfer device 70 is cleaned (step S5 in FIG. 3). . A detailed cleaning method of the back surface Sb of the second wafer S by the back surface cleaning device 90 will be described later.

The superposed wafer T whose back surface Sb of the second wafer S has been cleaned by the back surface cleaning device 90 is carried into the cleaning device 41 . In the cleaning device 41, the ground surface (back surface Wb) of the first wafer W is scrub-cleaned (step S6 in FIG. 3). Note that the back surface Sb of the second wafer S may be further cleaned together with the ground surface of the first wafer W in the cleaning device 41 .

Next, the superposed wafer T is transferred to the etching device 40 by the wafer transfer device 50 . In the etching device 40, the ground surface (back surface Wb) of the first wafer W is wet-etched with a chemical solution (step S7 in FIG. 3).

After that, the superposed wafer T that has undergone all the processes is transferred to the transition device 30 by the wafer transfer device 50 and further transferred to the cassette Ct on the cassette mounting table 10 by the wafer transfer device 20 . Thus, a series of wafer processing in the wafer processing system 1 is completed.

In the wafer processing described above, the back surface Sb of the second wafer S was cleaned after the grinding processing in the processing device 80. It may also be performed during transportation to the processing device 80 .

Next, a detailed configuration of the back surface cleaning apparatus 90 described above will be described. In the following description, in order to avoid complicating the description, the cleaning liquid used for grinding the back surface Wb in the processing device 80 and adhering to the back surface Sb is referred to as "cleaning liquid 80w", and the back surface cleaning device 90 cleans the back surface Sb. The cleaning liquid used at this time is sometimes called "cleaning liquid 90w". Also, the grinding dust adhering to the back surface Sb during the grinding of the back surface Wb in the processing device 80 and the cleaning liquid 80w may be collectively referred to as "grinding dust and the like".

As shown in FIGS. 4 and 5 , the back surface cleaning device 90 has a cleaning roller 91 , cleaning liquid nozzles 92 and squeeze rollers 93 . The cleaning roller 91, the cleaning liquid nozzle 92, and the squeezing roller 93 are used for cleaning the cleaning liquid 90w ejected from the cleaning liquid nozzle 92 when cleaning the back surface Sb, and the grinding dust and the like removed from the back surface Sb by cleaning the second wafer S. A cover body 94 is provided to prevent the dust from scattering to the outside. Further, below the cover body 94, a sink 95 is provided for receiving and discharging the cleaning liquid 90w, grinding dust, and the like.

The cleaning roller 91 as a water-absorbing roller is made of a member having water-absorbing properties, such as a sponge material, at least as a surface layer as a water-absorbing layer. The cleaning roller 91 is formed longer than at least the diameter of the second wafer S in the longitudinal direction. The cleaning roller 91 is provided so that its upper portion protrudes from an opening 94a of a cover body 94, which will be described later. By doing so, the grinding dust and the like adhering to the rear surface Sb are removed. The grinding dust and the like refer to the grinding dust and the cleaning liquid 80w attached when the back surface Wb of the first wafer W is ground in the processing apparatus 80 as described above.

The cleaning roller 91 is rotatable about its longitudinal axis by a drive mechanism 91a (for example, a servomotor). The direction of rotation of the cleaning roller 91 can be changed arbitrarily.

The cleaning liquid nozzle 92 is provided on the downstream side of the cleaning position of the back surface Sb in the rotation direction of the cleaning roller 91 , for example, on the side of the cleaning roller 91 so as to face the peripheral surface of the cleaning roller 91 . The cleaning liquid nozzle 92 has, for example, a plurality of cleaning liquid supply holes (not shown) in the longitudinal direction of the cleaning roller 91, and can supply the cleaning liquid 90w to the entire length of the cleaning roller 91 in the longitudinal direction. . The cleaning liquid nozzle 92 supplies the cleaning liquid 90w to the cleaning roller 91 to cause the cleaning roller 91 to absorb the cleaning liquid, and removes grinding debris and the like adhering to the peripheral surface of the cleaning roller 91 by cleaning the back surface Sb. Pure water, for example, can be used as the cleaning liquid 90w.

Shielding plates 96 and 97 for preventing scattering and transmission of the cleaning liquid 90w and the cleaning liquid 80w are provided in the vertical direction of the cleaning liquid nozzle 92 along the injection direction of the cleaning liquid 90w. The shielding plate 96 and the shielding plate 97 are provided so that their ends on the cleaning roller 91 side are close to the cleaning roller 91 to such an extent that the cleaning liquids 80w and 90w do not pass through the gaps between the cleaning roller 91 and the shielding plates 96 and 97. be done.

The shielding plate 96 is provided above the cleaning liquid nozzle 92 to prevent the cleaning liquid 90 w sprayed from the cleaning liquid nozzle 92 from adhering to the back surface Sb of the second wafer S after cleaning by the cleaning roller 91 . The shielding plate 97 is provided below the cleaning liquid nozzle 92, and the cleaning liquid 90w (contaminated water) that has been sprayed from the cleaning liquid nozzle 92 and has washed the cleaning roller 91 (contaminated water) and the cleaning liquid 80w that has been removed by cleaning are directed against the squeezing roller 93, which will be described later. to suppress the transmission of The shielding plate 97 is formed with holes (not shown) for discharging the cleaning liquid 90 w , the cleaning liquid 80 w and the contaminated water to the sink 95 .

The squeezing roller 93 is provided at least downstream of the cleaning liquid nozzle 92 in the rotation direction of the cleaning roller 91 , for example, below the cleaning roller 91 . The squeezing roller 93 is configured to be movable in contact and separation directions (vertical direction in the illustrated example) with respect to the cleaning roller 91 by a driving mechanism 93a (for example, a cylinder), thereby being configured to be freely pressed against the cleaning roller 91. It is The squeeze roller 93 cleans the back surface Sb and pushes out the cleaning liquid 90 w contained in the cleaning roller 91 by being pressed against the cleaning roller 91 absorbed by the cleaning liquid nozzle 92 . is reduced to a desired value, for example, a value that can appropriately absorb the cleaning liquid 80w adhering to the back surface Sb. Furthermore, when contaminated water remains on the cleaning roller 91 after cleaning by the cleaning liquid nozzle 92, the squeeze roller 93 can push out the contaminated water at the same time. Therefore, the back surface Sb can be washed again with the washing roller 91 in a clean state from which the contaminated water has been pushed out.

The cover body 94 is provided so as to accommodate and cover the cleaning roller 91, the cleaning liquid nozzle 92, and the squeezing roller 93, and the cleaning liquid 90w used in the back surface cleaning device 90 and the grinding dust removed by cleaning, etc. It suppresses scattering to the surroundings, that is, to the outside of the back surface cleaning device 90 .

An opening 94 a is formed in the upper surface of the cover body 94 . As described above, the upper portion of the cleaning roller 91 protrudes from the opening 94a, and the protrusion contacts the back surface Sb of the second wafer S passing above the back surface cleaning device 90, thereby cleaning the back surface Sb. .

An exhaust mechanism 94 b for exhausting the inside of the cover body 94 is further connected to the cover body 94 . The exhaust mechanism 94b exhausts the air from the inside of the cover body 94 to reduce the internal humidity, thereby suppressing malfunctions of the drive systems such as the drive mechanism 91a and the drive mechanism 93a due to humidity.

The sink 95 is provided below the cover body 94, that is, below the cleaning roller 91, the cleaning liquid nozzle 92, and the squeezing roller 93, and the cleaning liquid 90w, the contaminated water, and the removed grinding dust are provided at the bottom. It is discharged from the back surface cleaning device 90 through the discharge port 95a. The sink 95 is formed with a depth such that the squeezing roller 93 does not come into contact with the waste liquid discharged from the sink 95 at least when the squeezing roller 93 is lowered.

Next, a method for cleaning the back surface Sb using the back surface cleaning apparatus 90 configured as described above will be described.

In cleaning the back surface Sb of the second wafer S, preparations for cleaning the back surface Sb in the back surface cleaning device 90 are made prior to passing the superposed wafer T over the back surface cleaning device 90 .

In preparation for washing, as shown in FIG. 7A, the driving mechanism 91a rotates the washing roller 91 (step P1 in FIG. 6). The rotating direction of the cleaning roller 91 is forward with respect to the transfer direction of the superposed wafer T in this embodiment.

When the cleaning roller 91 starts rotating, next, as shown in FIG. 7B, the cleaning liquid 90w starts to be supplied from the cleaning liquid nozzle 92 toward the cleaning roller 91 (step P2 in FIG. 6). The cleaning roller 91 absorbs the cleaning liquid from the cleaning liquid nozzle 92 , and at least the surface layer of the cleaning roller 91 forms a first water absorbing region 91 w.

When the cleaning roller 91 is supplied with the cleaning liquid 90w and the cleaning roller 91 has sufficiently absorbed the cleaning liquid, the driving mechanism 93a raises the squeezing roller 93 and causes the cleaning roller 91 to move upward, as shown in FIG. (step P3 in FIG. 6). By pressing the squeezing roller 93 against the cleaning roller 91 in this manner, the cleaning liquid 90w contained in the cleaning roller 91 is pushed out from the cleaning roller 91, and the downstream side of the squeezing roller 93 in the rotation direction of the cleaning roller 91 is washed. The water absorption amount of the roller 91 cleaning liquid 90w is reduced. In this embodiment, the squeezing roller 93 does not have a rotating mechanism, and rotates together with the cleaning roller 91 by being pressed by the rotating cleaning roller 91 .

Thus, in the circumferential direction of the cleaning roller 91, the first water absorption region 91w (from the cleaning liquid nozzle 92 to the squeezing roller 93 in the rotation direction of the cleaning roller 91) and the second water absorption region 91d (the rotation direction of the cleaning roller 91). , from the squeezing roller 93 to the cleaning liquid nozzle 92), the preparation for cleaning the back surface Sb in the back surface cleaning device 90 is completed. The second water absorption region 91d is the water absorption amount of the cleaning roller 91 reduced by the squeezing roller 93 to a desired value, specifically, a value at which the cleaning liquid 80w adhering to the back surface Sb can be properly absorbed and removed. state.

When the preparation for cleaning in the back surface cleaning device 90 is completed, next, transfer of the superposed wafer T, which has undergone the grinding process in the processing device 80, from the processing device 80 to the cleaning device 41 is started (step P4 in FIG. 6). At this time, the rear surface cleaning device 90, which has been prepared for cleaning in step P3, is arranged below the transfer path of the superposed wafer T, and the rear surface Sb of the second wafer S of the superposed wafer T being transferred is cleaned. .

Here, the height at which the superposed wafer T is held by the wafer transfer device 70 is the height at which the rear surface Sb of the second wafer S during transfer comes into contact with the upper portion of the cleaning roller 91 protruding from the opening 94 a of the cover body 94 . maintained at As a result, the back surface Sb of the second wafer S transported by the wafer transport device 70 comes into contact with the top of the cleaning roller 91 when passing above the back surface cleaning device 90, as shown in FIG. 7(d). Grinding waste and the like adhering to the back surface Sb are removed and washed (step P5 in FIG. 6). At this time, it is the second water absorbing area 91d of the cleaning roller 91 formed in step P3 that comes into contact with the back surface Sb.

Specifically, the grinding waste adhering to the back surface Sb is removed by being sucked into the hole (not shown) of the cleaning roller 91 made of sponge material, or dropped directly into the sink 95. be. Further, the cleaning liquid 80w adhering to the back surface Sb is absorbed by the cleaning roller 91 having water absorbability, for example. In the back surface cleaning device 90 according to the present embodiment, the back surface Sb contacts the second water absorption region 91d. Therefore, the cleaning liquid 80w adhering to the back surface Sb is appropriately absorbed by the cleaning roller 91 and removed.

Here, when cleaning the back surface Sb with the cleaning roller 91, as shown in FIG. 91p (from the contact portion with the back surface Sb to the cleaning liquid nozzle 92 in the rotation direction of the cleaning roller 91) is formed. Specifically, when the second water absorption region 91d formed by the squeeze roller 93 contacts the back surface Sb, the grinding dust and the like adhering to the back surface Sb are absorbed by the cleaning roller 91, are absorbed, and become contaminated. .

The formed contaminated area 91p of the cleaning roller 91 is then cleaned by removing grinding dust and the like by spraying the cleaning liquid 90w from the cleaning liquid nozzle 92 (step P6 in FIG. 6). That is, the cleaning liquid nozzle 92 functions as a self-cleaning nozzle for the cleaning roller 91 in the back surface cleaning device 90 when cleaning the back surface Sb. Grinding wastes and the like removed by spraying the cleaning liquid 90w from the cleaning liquid nozzle 92 fall into, for example, the sink 95 and are removed.

Here, when the contaminated water generated by cleaning the contaminated area 91 p of the cleaning roller 91 is transmitted to the squeezing roller 93 , the squeezing roller 93 is contaminated with the contaminated water, and as a result, the second pressure after being pressed by the squeezing roller 93 is , the water absorption area 91d is contaminated, and as a result, there is a possibility that the back surface Sb cannot be washed properly. However, according to this embodiment, a shielding plate 97 is provided below the cleaning liquid nozzle 92 to suppress transmission of contaminated water to the squeeze roller 93 . That is, according to this embodiment, the back surface Sb of the second wafer S can be cleaned appropriately. The generated contaminated water is guided to the sink 95 through the hole (not shown) provided in the shielding plate 97 and removed.

The contaminated area 91p cleaned by the cleaning liquid 90w supplied from the cleaning liquid nozzle 92 becomes the first water absorption area 91w again as shown in FIG. After the second water absorption region 91d is formed, the rear surface Sb is again contacted and washed.

Then, when the superposed wafer T passes over the back surface cleaning device 90 by the wafer transfer device 70, in other words, when the entire surface of the back surface Sb of the second wafer S is cleaned by the cleaning roller 91, the back surface cleaning device 90 Cleaning of the back surface Sb is completed. The polymerized wafer T whose back surface Sb has been cleaned is then transported to the cleaning device 41 and scrub-cleaned (step S6 in FIG. 3).

Although the cleaning of the back surface Sb of the second wafer S is completed as described above, after the cleaning of the back surface Sb is completed, the suction holding surface 71a of the wafer transfer device 70 may be further cleaned by the back surface cleaning device 90. . Such cleaning of the suction holding surface 71a may be performed each time the superposed wafer T is processed, or may be performed after the process of all the superposed wafers T accommodated in the cassette Ct is completed.

The method for cleaning the suction holding surface 71a is the same as the method for cleaning the back surface Sb of the second wafer S. FIG. That is, cleaning is performed by bringing the suction holding surface 71a of the wafer transfer device 70 into contact with the cleaning roller 91 in a state in which the superposed wafer T is not held. In such a case, the height of the suction holding surface 71a needs to be lowered by the thickness of the superposed wafer T in order to bring the suction holding surface 71a into contact with the cleaning roller 91 appropriately.

After that, as shown in FIG. 8A, when all the processes by the back surface cleaning device 90 are completed, the back surface cleaning device 90 is stopped. When stopping the back surface cleaning device 90, first, as shown in FIG. 8B, the drive mechanism 93a retracts the squeeze roller 93 from the cleaning roller 91 (step P8 in FIG. 6).

After the squeeze roller 93 is lowered, as shown in FIG. 8C, the supply of the cleaning liquid 90w from the cleaning liquid nozzle 92 to the cleaning roller 91 is stopped (step P9 in FIG. 6).

After stopping the supply of the cleaning liquid 90w from the cleaning liquid nozzle 92, finally, as shown in FIG. 8D, the driving mechanism 91a stops rotating the cleaning roller 91 (step P10 in FIG. 6). Thus, a series of cleaning of the back surface Sb in the back surface cleaning device 90 is completed.

As described above, according to the back surface cleaning apparatus 90 according to the present embodiment, in the superposed wafer T after the back surface Wb of the first wafer W has been ground, grinding dust and the like adhered to the back surface Sb of the second wafer S (ground Debris and cleaning fluid 80w) can be adequately removed. At this time, since the cleaning roller 91 contacts the back surface Sb in a state where the amount of water absorbed by the squeezing roller 93 is reduced, the cleaning liquid 80w adhering to the back surface Sb can be absorbed more appropriately.

Further, according to the present embodiment, the cleaning liquid nozzle 92 can clean the contaminated area 91p of the cleaning roller 91 after cleaning the back surface Sb, so that the back surface Sb can be appropriately cleaned without being contaminated by the contaminated area 91p. . After cleaning the contaminated area 91p by the cleaning liquid nozzle 92, the squeeze roller 93 is pressed against the first water absorption area 91w to push out the cleaning liquid 90w of the cleaning roller 91 and reduce the amount of water absorption. Even when cleaning is performed, the cleaning liquid 80w adhering to the back surface Sb can be properly absorbed, and the back surface Sb can be cleaned more appropriately. Further, at this time, since the contaminated water contained in the cleaning roller 91 can be pushed out by the squeeze roller 93 at the same time, the back surface Sb can be cleaned more appropriately.

Further, a shielding plate 97 is provided below the cleaning liquid nozzle 92 along the injection direction of the cleaning liquid 90w. As a result, contaminated water generated by cleaning the cleaning roller 91 is suppressed from reaching the squeeze roller 93, and the back surface Sb can be cleaned more appropriately.

Further, according to this embodiment, a cover body 94 is provided so as to cover the cleaning roller 91 and the cleaning liquid nozzle 92, and a shielding plate 96 is provided above the cleaning liquid nozzle 92 along the injection direction of the cleaning liquid 90w. there is As a result, it is possible to appropriately prevent the cleaning liquid 90w sprayed from the cleaning liquid nozzle 92 from directly adhering to the back surface Sb and contaminating the exterior of the back surface cleaning device 90 .

Further, according to this embodiment, the cleaning roller 91 is rotated in the forward direction with respect to the transfer direction of the superposed wafer T by the wafer transfer device 70 . This prevents the cleaning liquid 90w from scattering to the back surface Wb of the first wafer W when the back surface Sb of the second wafer S and the cleaning roller 91 come into contact with each other.

Further, according to this embodiment, the cleaning roller 91 is formed at least larger than the diameter of the second wafer S in the longitudinal direction. As a result, the cleaning roller 91 can be appropriately brought into contact with the entire surface of the back surface Sb when the second wafer S passes through, that is, the back surface Sb can be properly cleaned.

Furthermore, according to this embodiment, when the back surface cleaning device 90 is stopped, the supply of the cleaning liquid 90w from the cleaning liquid nozzle 92 is stopped after the squeeze roller 93 is retracted from the cleaning roller 91 . As a result, the squeezing roller 93 is suppressed from being pressed against the cleaning roller 91 in a dry state, and the effect of permanent deformation of the cleaning roller 91 by the squeezing roller 93 is suppressed, thereby properly shortening the life of the cleaning roller 91. can be suppressed.

Similarly, according to the present embodiment, since the supply of the cleaning liquid 90w from the cleaning liquid nozzle 92 is started before the pressing of the squeezing roller 93 against the cleaning roller 91 when the back surface cleaning device 90 is started, the permanent strain caused by the squeezing roller 93 is reduced. can be suppressed more appropriately.

Note that the configuration of the back surface cleaning device 90 is not limited to the above embodiment. For example, in the above embodiment, only one cleaning roller 91 was used to clean the back surface Sb of the second wafer S. However, a plurality of cleaning rollers 91 may be provided below the transfer path of the superposed wafer T. .

Further, for example, as shown in FIG. 9, a fluid nozzle 110 for ejecting a fluid such as air or cleaning water to the rear surface Sb is further provided on the upstream side of the cleaning roller 91 in the conveying path of the superposed wafer T. good too. By providing the fluid nozzle 110 in this manner, the fluid can be jetted onto the back surface Sb before contact with the cleaning roller 91 to remove grinding dust and the like in advance, and cleaning by the cleaning roller 91 can be performed more easily. .

Also, the arrangement of the cleaning liquid nozzles 92 and the squeezing rollers 93 with respect to the cleaning roller 91 is not limited to the above embodiment, and can be arranged arbitrarily. However, from the viewpoint of quickly cleaning the contaminated region 91p after cleaning the back surface Sb, the cleaning liquid nozzle 92 is preferably arranged close to the contact portion with the back surface Sb. In addition, the squeeze roller 93 may be arranged below the cleaning roller 91 from the viewpoint of suppressing the washing liquid 90w removed by the pressure of the squeeze roller 93 from being transmitted downward and being absorbed by the washing roller 91 again. preferable.

Furthermore, in the above-described embodiment, the squeeze roller 93 does not have a rotating mechanism and is rotated together by being pressed against the cleaning roller 91. However, the squeeze roller 93 may be further provided with a rotating mechanism.

In the above embodiment, the supply of the cleaning liquid 90w from the cleaning liquid nozzle 92 is stopped after the squeezing roller 93 is retracted in order to suppress the influence of permanent strain on the cleaning roller 91. can be retracted, the squeeze roller 93 may be retracted after the supply of the cleaning liquid 90w is stopped.

In the above embodiment, the direction of rotation of the cleaning roller 91 is forward with respect to the transport direction of the superposed wafer T, but the direction of rotation of the cleaning roller 91 is not necessarily limited to this. For example, by setting the rotating direction of the cleaning roller 91 to be opposite to the conveying direction of the superposed wafer T, the cleaning power of the cleaning roller 91 for the back surface Sb can be improved.

In the above embodiment, the back surface Sb is cleaned after the grinding process. Therefore, when the height at which the superposed wafer T is held by the wafer transfer device 70 is constant, the cleaning roller 91 and the back surface Sb do not come into contact with each other even when cleaning is unnecessary when the superposed wafer T is carried into the processing device 80. There is a risk of Therefore, in this embodiment, it is preferable to control the holding height of the superposed wafer T by the wafer transfer device 70 . Specifically, it is preferable that the cleaning roller 91 and the back surface Sb are at a height at which the cleaning roller 91 does not come into contact with the back surface Sb when the superposed wafer T is carried into the processing device 80, and at a height where the cleaning roller 91 and the back surface Sb come into contact with each other at the time of carrying out.

In the above embodiment, the case of cleaning the back surface Sb of the second wafer S in the superposed wafer T in which the first wafer W and the second wafer S are bonded in the back surface cleaning device 90 will be described as an example. However, the wafer to be cleaned in the back surface cleaning device 90 is not limited to this. For example, the back surface cleaning apparatus 90 may clean a device wafer (first wafer W), and such a device wafer may not be bonded to the support wafer (second wafer S). In such a case, the device wafer may not have the surface film Fw formed thereon.

It should be considered that the embodiments disclosed this time are illustrative in all respects and not restrictive. The embodiments described above may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims.

1 Wafer Processing System 70 Wafer Transfer Device 71a Suction Holding Surface 90 Backside Cleaning Device 91 Cleaning Roller 91a Drive Mechanism 92 Cleaning Liquid Nozzle 93 Squeezing Roller Sb (Second Wafer) Backside T Polymerization Wafer Wb (First Wafer) Backside

Claims (20)

A substrate processing apparatus for processing a substrate,
a substrate transport mechanism that holds and transports one surface of the substrate;
a cleaning mechanism provided below a transport path of the substrate by the substrate transport mechanism for cleaning the other surface of the substrate;
The cleaning mechanism is
a water absorbing roller that is rotatable by a drive mechanism and has a water absorbing layer on at least the surface layer of the peripheral surface;
a cleaning liquid nozzle that supplies cleaning liquid to the water absorbing roller;
a squeezing roller provided on the downstream side of the cleaning liquid nozzle in the rotation direction of the water absorbing roller and configured to be movable in a contacting/separating direction with respect to the water absorbing roller;
A substrate processing apparatus for cleaning the other surface of the substrate by bringing the water absorbing roller into contact with the other surface of the substrate. The cleaning mechanism is
2. The substrate processing apparatus according to claim 1, further comprising a shielding plate along the spray direction of said cleaning liquid below said cleaning liquid nozzle. The cleaning mechanism is
3. The substrate processing apparatus according to claim 1, further comprising a shielding plate above said cleaning liquid nozzle along the direction in which said cleaning liquid is sprayed. a cover body provided to accommodate the cleaning mechanism and having an opening formed on an upper surface thereof;
4. The substrate processing apparatus according to claim 1, wherein an upper portion of said water absorbing roller that contacts another surface of said substrate protrudes from said opening. 5. The substrate processing apparatus according to claim 4, further comprising an exhaust mechanism for exhausting the inside of said cover body. The cleaning mechanism is
The substrate processing apparatus according to any one of claims 1 to 5, further comprising a fluid nozzle provided upstream of said water absorbing roller in said transport path of said substrate and supplying fluid to said other surface. . 7. The substrate processing apparatus according to claim 1, wherein a direction of rotation of said water absorbing roller by said drive mechanism is forward with respect to a conveying direction of said substrate. 8. The substrate processing apparatus according to claim 1, wherein said water absorbing roller has a size equal to or larger than the diameter of said substrate in the longitudinal direction. The substrate transport mechanism sucks and holds one surface of the substrate with a suction holding surface,
The substrate processing apparatus according to any one of claims 1 to 8, wherein the cleaning mechanism cleans the suction holding surface while the substrate transfer mechanism does not hold the substrate . 10. The substrate processing apparatus according to claim 9, wherein said substrate transport mechanism is configured such that said suction holding surface is movable in a contacting/separating direction with respect to said cleaning mechanism. A substrate processing method for processing a substrate after grinding,
transporting the substrate, one surface of which is held by a substrate transport mechanism;
cleaning the other surface of the transported substrate with a cleaning mechanism;
In cleaning the other surface,
supplying the cleaning liquid from the cleaning liquid nozzle to the water absorbing roller rotated by the drive mechanism;
pressing a squeezing roller against the water absorbing roller supplied with the cleaning liquid to reduce the water absorption amount of the water absorbing roller;
and bringing the water-absorbing roller having a reduced amount of water absorption into contact with the other surface. 12. The substrate processing method according to claim 11, wherein said squeeze roller is pressed against said water absorbing roller by a driving mechanism after said water absorbing roller absorbs said cleaning liquid from said cleaning liquid nozzle. cleaning the water absorbing roller in contact with the other surface by supplying cleaning liquid from the cleaning liquid nozzle;
pressing a squeezing roller against the water absorbing roller supplied with the cleaning liquid to reduce the water absorption amount of the water absorbing roller;
13. The substrate processing method according to claim 11, wherein the substrate is brought into contact with the other surface again. 14. The substrate processing method according to any one of claims 11 to 13, comprising supplying fluid from a fluid nozzle to the other surface of said substrate before contacting said water absorbing roller. 15. The substrate processing method according to claim 11, wherein said water absorbing roller is rotated in a forward direction with respect to a transport direction of said substrate by said substrate transport mechanism. The cleaning mechanism is provided inside a cover body having an opening on the upper surface through which the upper part of the water absorbing roller protrudes,
16. The substrate processing method according to any one of claims 11 to 15, comprising exhausting the inside of said cover body by an exhaust mechanism. The substrate transport mechanism sucks and holds one surface of the substrate with a suction holding surface,
17. The substrate processing method according to any one of claims 11 to 16 , comprising cleaning said adsorption holding surface while said substrate transport mechanism does not hold said substrate . The cleaning mechanism is
18. The substrate processing method according to claim 11, wherein the supply of the cleaning liquid from the cleaning liquid nozzle is stopped after the squeezing roller is withdrawn from the water absorbing roller. The cleaning mechanism is
The squeezing roller is retracted from the water absorbing roller after stopping the supply of the cleaning liquid from the cleaning liquid nozzle and before the water absorbing roller dries. Substrate processing method. grinding one surface of the substrate in a processing device;
The substrate transport mechanism changes a holding height of the substrate when the substrate is loaded into the processing apparatus and when the substrate is unloaded, and the other surface is cleaned when the substrate is unloaded. Item 20. The substrate processing method according to any one of Items 11 to 19.

Images