KR20200095564A - Substrate processing system, substrate processing method and computer storage medium - Google Patents

Abstract

A substrate processing system for processing a substrate includes a first grinding wheel in contact with a peripheral portion of the substrate, a first peripheral edge removal portion for grinding and removing the peripheral edge portion to a first depth, and a second peripheral edge portion in contact with the peripheral edge portion of the substrate It has a grinding stone, and after removing the peripheral portion by the first peripheral edge removal portion, has a second peripheral edge removing portion for removing by grinding the peripheral edge to a second depth deeper than the first depth, the second grinding stone is provided The particle size of the abrasive grains is smaller than that of the abrasive grains provided by the first grinding stone.

Description

Substrate processing system, substrate processing method and computer storage medium

This application claims priority based on patent application 2017-243303 for which it applied to Japan on December 19, 2017, and uses the content here.

The present invention relates to a substrate processing system for processing a substrate, a substrate processing method using the substrate processing system, and a computer storage medium.

In recent years, in the manufacturing process of semiconductor devices, for semiconductor wafers (hereinafter referred to as ``wafers'') on which devices such as a plurality of electronic circuits are formed, grinding and polishing the back surface of the wafer to thin the wafer. Is being done. In addition, when the thinned wafer is conveyed as it is or subsequent processing is performed, there is a risk of warping or cracking in the wafer. For this reason, in order to reinforce the wafer, for example, attaching the wafer to the support substrate is performed.

By the way, the periphery of the wafer is usually chamfered, but when the wafer is subjected to grinding and polishing treatment as described above, the periphery of the wafer has a sharp pointed shape. Then, chipping occurs at the periphery of the wafer, and there is a fear that the wafer may be damaged. Therefore, so-called edge trimming, in which the periphery of the wafer is cut beforehand before the grinding treatment, is performed.

For example, Patent Document 1 discloses a vertical axis type plane grinding device as an edge trimming device. In the case of grinding the periphery of the wafer by using this vertical axis type plane grinding device, the wafer is first fixed to a table, and the table is rotated around an axis parallel to the vertical axis. Then, after the spindle is rotated and the cup wheel is rotated, the spindle is moved in the vertical direction to bring the grinding surface of the cup wheel into contact with the wafer to grind the peripheral edge of the wafer.

Japanese Patent Laid-Open Publication No. Hei 09-216152

As described above, in the surface grinding apparatus described in Patent Document 1, the peripheral portion of the wafer is ground using a cup wheel. Here, for example, in order to increase the grinding speed of the periphery, it is necessary to increase the grain size of the abrasive grain of the cup wheel. However, in this case, the surface of the exposed wafer (hereinafter, referred to as “exposed surface”) is roughened by grinding the peripheral portion, so that the predetermined quality may not be satisfied.

On the other hand, in order to improve the surface properties and condition of the exposed surface of the wafer, for example, it is necessary to reduce the grain size of the abrasive grains of the cup wheel. However, in this case, it takes time to grind the peripheral portion, and the throughput of the entire wafer processing cannot be improved. Therefore, there is room for improvement in the edge trim using the cup wheel as in the prior art.

The present invention has been made in view of the above circumstances and aims to improve the surface properties and conditions of the surface of the substrate exposed by grinding the peripheral edge while reducing the time taken to remove the peripheral edge when grinding and removing the peripheral edge of the substrate. .

An aspect of the present invention for solving the above problem is a substrate processing system for processing a substrate, comprising a first grinding stone in contact with a peripheral edge of the substrate, and grinding the peripheral edge to a first depth to remove the first peripheral agent. A second grinding wheel comprising a rejection and a second grinding stone in contact with a peripheral portion of the substrate, and after removing the peripheral portion by the first peripheral edge removal portion, the peripheral edge portion is further ground to a second depth deeper than the first depth to remove the It has 2 peripheral edge removal part, and the particle size of the abrasive grain provided by the said 2nd grinding stone is smaller than the particle size of the abrasive grain provided by the said 1st grinding stone.

An aspect of the present invention according to another aspect is a substrate processing method for treating a substrate, comprising: a first peripheral edge removal step of contacting a first grindstone to a peripheral edge of the substrate and grinding and removing the peripheral edge to a first depth; Thereafter, the second grinding wheel is brought into contact with the periphery of the substrate to remove the periphery by grinding and removing the periphery to a second depth deeper than the first depth, and the grain size of the abrasive provided by the second grinding stone Is smaller than the particle size of the abrasive grain provided by the first grinding stone.

According to another aspect of the present invention, there is provided a readable computer storage medium storing a program running on a computer of a control unit that controls the substrate processing system so that the substrate processing method is executed by the substrate processing system.

According to an aspect of the present invention, in grinding and removing the peripheral portion of the substrate, by using the first grinding stone, the time required to remove the peripheral portion can be shortened, and the throughput of the substrate processing can be improved. Further, by using the second grindstone, it becomes possible to improve the surface properties and conditions of the surface of the substrate exposed by grinding the periphery.

1 is a plan view schematically showing a configuration of a substrate processing system according to the present embodiment.
2 is a side view schematically showing the configuration of a superposed wafer.
3 is a plan view schematically showing a configuration of a processing device.
4 is a side view schematically showing a configuration of a first peripheral edge removing portion (a second peripheral edge removing portion).
Fig. 5 is an explanatory diagram schematically showing the configuration of a first peripheral edge removing portion (second peripheral edge removing portion).
6 is a flow chart showing the main steps of wafer processing.
7 is an explanatory diagram showing a state in which a processing target wafer is ground in a main process of wafer processing.
8 is an explanatory view showing a state in which a corner portion of a bottom surface of a second peripheral edge portion is curved when a second peripheral edge portion of the wafer to be processed is removed.
Fig. 9 is an explanatory view showing a state in which the grinding surface of the second grinding wheel is adjusted with a dress board.
10 is a plan view schematically showing a configuration of a substrate processing system according to another embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, elements having substantially the same functional configuration in the present specification and drawings are denoted by the same reference numerals, so that redundant descriptions are omitted.

<Substrate processing system>

First, the configuration of the substrate processing system according to the present embodiment will be described. 1 is a plan view schematically showing a configuration of a substrate processing system 1. In the following, in order to clarify the positional relationship, an X-axis direction, a Y-axis direction, and a Z-axis direction orthogonal to each other are defined, and the positive Z-axis direction is a vertically upward direction.

In the substrate processing system 1 of the present embodiment, as shown in FIG. 2, for example, a polymerized wafer (T) in which a wafer to be processed W and a support wafer S as a substrate are bonded via an adhesive G. ) Is processed, and the processing target wafer W is thinned. Hereinafter, in the processing target wafer (W), the surface to be processed (grind) (the surface opposite to the surface to which the adhesive (G) is adhered) is referred to as the'processed surface (W1)', and the surface opposite to the processing surface (W1) Cotton is called'unprocessed surface (W2)'. In addition, in the support wafer (S), the surface bonded to the target wafer (W) via the adhesive (G) is referred to as'bonded surface (S1)', and the side opposite to the bonding surface (S1) is'non-bonded. It is called cotton (S2)'. Further, in the present embodiment, the processing target wafer W and the support wafer S are bonded via an adhesive G, but the bonding method is not limited thereto.

The processing target wafer W is, for example, a semiconductor wafer such as a silicon wafer or a compound semiconductor wafer, and a plurality of devices are formed on the unprocessed surface W2. Further, the periphery of the to-be-processed wafer W is chamfered, and the end face of the periphery has a smaller thickness toward its tip.

The supporting wafer S is a wafer supporting the processing target wafer W. In addition, the support wafer S functions as a protective material for protecting the device of the unprocessed surface W2 of the processing target wafer W together with the adhesive G. Further, in the present embodiment, a case in which a wafer is used as the supporting substrate is described, but other substrates such as a glass substrate may be used.

As shown in FIG. 1, the substrate processing system 1 includes, for example, a carrying-in/out station 2 in which a cassette C capable of accommodating a plurality of superposed wafers T is carried in and out from the outside, and a superposed wafer It has a configuration in which a processing station 3 equipped with various processing devices that performs a predetermined processing on (T) is connected.

A cassette mounting table 10 is provided in the carry-in/out station 2. In the illustrated example, a plurality of, for example, four cassettes C can be arranged in a row in the X-axis direction on the cassette mounting table 10.

A wafer transfer area 20 is provided in the carry-in/out station 2 adjacent to the cassette mounting table 10. The wafer transfer area 20 is provided with a wafer transfer device 22 capable of moving on a transfer path 21 extending in the X-axis direction. The wafer transfer device 22 has, for example, two transfer arms 23 and 23 that hold and transfer the superimposed wafer T. Each of the conveying arms 23 is configured to be movable in a horizontal direction, a vertical direction, a horizontal axis circumference, and a vertical axis circumference. In addition, the structure of the conveyance arm 23 is not limited to this embodiment, It can take arbitrary structure.

The processing station 3 is provided with a wafer transfer area 30. The wafer transfer area 30 is provided with a wafer transfer device 32 capable of moving on a transfer path 31 extending in the Y-axis direction. The wafer transfer device 32 has, for example, two transfer arms 33 and 33 that hold and transfer the polymerized wafer T. Each of the conveying arms 33 is configured to be movable in a horizontal direction, a vertical direction, a horizontal axis circumference, and a vertical axis circumference. In addition, the structure of the conveyance arm 33 is not limited to this embodiment, It can take arbitrary structure.

In the processing station 3, around the wafer transfer area 30, a processing device 40, a CMP device 41 (CMP: Chemical Mechanical Polishing, chemical mechanical polishing), a first peripheral edge removal device 42, The 2nd circumferential removal device 43, the 1st cleaning device 44, and the 2nd cleaning device 45 are provided. On the side of the X-axis negative direction of the wafer transfer region 30, a processing apparatus 40 and a CMP apparatus 41 are arranged and arranged from the positive Y-axis direction toward the negative direction. A first edge removal device 42 and a second edge removal device 43 are arranged on the side of the wafer transfer region 30 in the positive X-axis direction from the positive Y-axis direction toward the negative direction. A first cleaning device 44 and a second cleaning device 45 are arranged above the wafer transfer region 30 in the negative Y-axis direction from the positive Y-axis direction. Further, a transition device (not shown) for transferring the superimposed wafer T between the wafer transfer device 22 and the wafer transfer device 32 is provided below the second cleaning device 45.

The above substrate processing system 1 is provided with a control unit 50. The control unit 50 is, for example, a computer, and has a program storage unit (not shown). In the program storage unit, a program for controlling the processing of the superimposed wafer T in the substrate processing system 1 is stored. In addition, the program storage unit also stores a program for controlling the operation of a drive system such as the above-described various processing devices or transfer devices to realize wafer processing described later in the substrate processing system 1. In addition, the program is stored in a computer-readable storage medium (H) such as a computer-readable hard disk (HD), a flexible disk (FD), a compact disk (CD), a magnetic optical disk (MO), and a memory card. It may have been recorded and installed in the control unit 50 from the storage medium H.

(Processing device)

As shown in FIG. 3, the processing apparatus 40 includes a rotary table 100, a conveyance unit 110, an alignment unit 120, a cleaning unit 130, a rough grinding unit 140, and an intermediate grinding unit 150. And a finish grinding unit 160.

The rotary table 100 is configured to be rotatable by a rotating mechanism (not shown). On the turntable 100, four chucks 101 for adsorbing and holding the superimposed wafer T are provided. The chuck 101 is evenly arranged on the same circumference as the rotary table 100, that is, every 90 degrees. The four chucks 101 are movable to the transmission position A0 and the processing positions A1 to A3 by rotating the rotary table 100.

In this embodiment, the delivery position A0 is a position in the X-axis positive direction and the Y-axis negative direction side of the rotary table 100, and the alignment unit 120 and the cleaning unit are located on the Y-axis negative direction side of the delivery position A0. 130 is placed. The first machining position A1 is a position of the rotary table 100 in the X-axis positive direction and the Y-axis positive direction, and the rough grinding unit 140 is disposed. The second processing position A2 is a position on the negative X-axis direction side and the positive Y-axis side of the rotary table 100, and the intermediate grinding unit 150 is disposed. The 3rd machining position A3 is a position in the X-axis negative direction side and the Y-axis negative direction side of the rotary table 100, and the finish grinding unit 160 is arrange|positioned.

The chuck 101 is held on the chuck base 102. The chuck 101 and the chuck base 102 are configured to be rotatable by a rotation mechanism (not shown).

The transfer unit 110 is a multi-joint type robot including a plurality of, for example, three arms 111 to 113. The three arms 111 to 113 are connected by joints (not shown), and by these joints, the first arm 111 and the second arm 112 are each configured to be pivotable around the proximal end. . Among the three arms 111 to 113, a transfer pad 114 for adsorbing and holding the superimposed wafer T is attached to the first arm 111 at the tip end. Further, of the three arms 111 to 113, the third arm 113 at the base end is attached to the vertical movement mechanism 115 that moves the arms 111 to 113 in the vertical direction. In addition, the transfer unit 110 having such a configuration can transfer the superimposed wafer T to the transfer position A0, the alignment unit 120, and the cleaning unit 130.

In the alignment unit 120, the direction in the horizontal direction of the superimposed wafer T before the grinding treatment is adjusted. For example, while rotating the polymerization wafer T held on a spin chuck (not shown), by detecting the position of the notch portion of the polymerization wafer T with a detection unit (not shown), the position of the notch portion is adjusted to perform polymerization. The direction of the horizontal direction of the wafer T is adjusted.

In the cleaning unit 130, the non-bonded surface S2 of the support wafer S in a state in which the polymerized wafer T after the grinding treatment is held on the transfer pad 114 is cleaned, and the transfer pad 114 is further cleaned. do.

In the rough grinding unit 140, the processing surface W1 of the processing target wafer W is roughly ground. The coarse grinding unit 140 has a coarse grinding part 141 provided with a coarse grinding wheel (not shown) rotatable in an annular shape. In addition, the rough grinding portion 141 is configured to be movable in the vertical direction and the horizontal direction along the post 142. Then, by rotating the chuck 101 and the rough grinding stone, respectively, in a state in which the processing target wafer W held by the chuck 101 is brought into contact with the rough grinding stone, the processed surface W1 of the processing target wafer W To rough grinding.

In the intermediate grinding unit 150, the processing surface W1 of the processing target wafer W is intermediately ground. The intermediate grinding unit 150 has an intermediate grinding part 151 provided with an intermediate grinding stone (not shown) rotatable in an annular shape. In addition, the intermediate grinding portion 151 is configured to be movable in the vertical direction and the horizontal direction along the post 152. Further, the grain size of the intermediate grinding wheel is smaller than the grain size of the coarse grinding wheel. And, in a state in which the processing surface W1 of the processing target wafer W held in the chuck 101 is brought into contact with the intermediate grinding stone, the processing surface W1 is intermediate by rotating the chuck 101 and the intermediate grinding stone respectively. To grind.

The finish grinding unit 160 finishes grinding the processed surface W1 of the processing target wafer W. The finish grinding unit 160 has a finish grinding section 161 provided with a finish grinding wheel (not shown) rotatable in an annular shape. In addition, the finish grinding unit 161 is configured to be movable in the vertical direction and the horizontal direction along the post 162. In addition, the grain size of the abrasive grain of the finish grinding stone is smaller than the grain size of the intermediate grinding stone. And, in a state in which the processed surface W1 of the processing target wafer W held in the chuck 101 is brought into contact with the finishing grinding stone, the processing surface W1 is finished by rotating the chuck 101 and the finishing grinding stone respectively. To grind.

(CMP device)

The CMP apparatus 41 shown in FIG. 1 includes, for example, two polishing units (not shown) for polishing the processed surface W1 of the processing target wafer W. The grain size of the abrasive grains used in the first polishing portion is larger than the grain size of the abrasive grains used in the second polishing portion. Then, the processing surface W1 is roughly polished in the first polishing unit, and the processed surface W1 is finished polishing in the second polishing unit. Further, as the configuration of the CMP device 41, a general configuration in which chemical polishing treatment is performed can be adopted. For example, processing may be performed in a so-called face-up state with the processing surface W1 of the processing target wafer W facing upward, or processing in a so-called face-down state with the processing surface W1 facing downward. You may do it.

(Perimeter removal device)

The first edge removal device 42 and the second edge removal device 43 respectively remove the periphery of the wafer W to be processed. That is, in the substrate processing system 1, the peripheral portion of the processing target wafer W is removed in two steps.

The first peripheral edge removal device 42 has a chuck 200 as a substrate holding portion for holding a superimposed wafer T (wafer W to be processed). The chuck 200 is supported by the chuck table 201 and is configured to be movable on a conveyance path 202 extending in the X-axis direction. Further, the chuck 200 is configured to be rotatable by a rotation mechanism (not shown). In addition, in this embodiment, the chuck table 201 and the conveyance path 202 constitute the moving mechanism of the present invention. In addition, in the moving mechanism of the present invention, the chuck 200 and the first grinding wheel 211 to be described later may be moved in a relatively horizontal direction, and the first grinding wheel 211 may be moved in the horizontal direction, or the chuck ( 200) and both of the first grinding wheel 211 may be moved in the horizontal direction.

In addition, the first peripheral edge removal device 42 has a first peripheral edge removal portion 210 disposed above the chuck 200 to remove a peripheral edge of the processing target wafer W held on the chuck 200. . As shown in FIG. 4, the 1st peripheral edge removal part 210 has a 1st grindstone wheel 211, a support wheel 212, a spindle 213, and a drive part 214.

The support wheel 212 to which the first grinding wheel 211 is fixed is supported by the spindle flange 213a of the spindle 213, and the spindle 213 is provided with a drive part 214. The drive unit 214 has a built-in motor (not shown), for example, and rotates the first grinding wheel 211 and the support wheel 212 through the spindle 213. In addition, the spindle 213 and the drive unit 214 are configured to be able to move up and down by the lifting mechanism 215.

As shown in FIG. 5, the 1st grindstone wheel 211 and the support wheel 212 each have an annular shape (ring shape) in plan view. The first grindstone wheel 211 contains abrasive grains, comes into contact with the peripheral edge We of the processing target wafer W, and grinds and removes the peripheral edge We. In addition, in this embodiment, although the 1st grindstone wheel 211 is provided in an annular shape, it is not limited to this, For example, it may be provided by being divided along the support wheel 212.

In the first peripheral edge removal device 42, first, the processing target wafer W is moved in a horizontal direction, so that the range in which the first grinding wheel 211 contacts the processing target wafer W has a predetermined width and a predetermined width. Arrange the first grinding wheel 211 to match.

Next, in a state in which the first grinding wheel 211 is lowered and brought into contact with the peripheral portion We of the processing target wafer W, the first grinding wheel 211 and the polymerized wafer T (processed wafer W) By rotating each, the periphery (We) is removed by grinding. In addition, at this time, from the state in which the first grinding wheel 211 is in contact with the processed surface W1 of the processing target wafer W, by moving the first grinding wheel 211 vertically downward, the peripheral portion We is moved. Remove by grinding from top to bottom.

In addition, the second peripheral edge removal device 43 has the same configuration as the first edge removal device 42. That is, as shown in Figs. 1 and 4, the second edge removal device 43 includes a chuck 220, a chuck table 221, a conveyance path 222, and a second edge removal unit 230 (a second grinding wheel 231, a support wheel 232, a spindle 233, a drive unit 234, and an elevating mechanism 235. However, the grain size of the abrasive grain of the second grinding wheel 231 is smaller than the grain size of the abrasive grain of the first grinding wheel 211.

(Cleaning device)

As shown in FIG. 1, in the first cleaning device 44, the processing surface W1 of the processing target wafer W is roughly cleaned, and in the second cleaning device 45, the processing surface W1 of the processing target wafer W is performed. ) To finish washing.

The first cleaning device 44 includes a spin chuck 300 that holds and rotates the polymerized wafer T, and a scrub cleaning tool 301 provided with a brush, for example. Then, the processed surface W1 is cleaned by contacting the scrub cleaning tool 301 with the processing surface W1 of the processing target wafer W while rotating the polymerized wafer T held by the spin chuck 300. .

The second cleaning device 45 includes a spin chuck 310 for holding and rotating the polymerized wafer T, and a nozzle 311 for supplying a cleaning liquid, such as pure water, to the processing surface W1 of the processing target wafer W. ). Then, the cleaning liquid is supplied from the nozzle 311 to the processing surface W1 of the processing target wafer W while rotating the superimposed wafer T held by the spin chuck 310. Then, the supplied cleaning liquid diffuses over the processing surface W1, and the processing surface W1 is cleaned.

<Wafer treatment>

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

First, a cassette C containing a plurality of superimposed wafers T is placed on the cassette mounting table 10 of the carry-in/out station 2. In the cassette C, the superposed wafer T is accommodated so that the processing surface W1 of the processing target wafer W faces upward.

Subsequently, the polymerized wafer T in the cassette C is taken out by the wafer transfer device 22, and the polymerized wafer T is transferred to the wafer transfer device 32 via a transition device (not shown). , It is conveyed to the first smoke removal device 42 of the treatment station 3. The first peripheral edge removal device 42 removes the peripheral edge We of the to-be-processed wafer W. In the following description, the peripheral edge We removed by the first edge removal device 42 is referred to as the first peripheral edge. There is a case called (We1).

The superimposed wafer T conveyed by the first peripheral edge removal device 42 is held by the chuck 200. And, as shown in Fig.7 (a), by moving the first grinding wheel 211 vertically downward, while rotating the first grinding wheel 211, the first peripheral edge (We1) of the processing target wafer (W) Contact with At this time, the range of the first grinding wheel 211 in contact with the processing target wafer W is a predetermined circumferential first width L1 (distance from the end of the processing target wafer W). ).

Thereafter, in a state in which the first grinding wheel 211 is brought into contact with the first peripheral portion We1, the first grinding wheel 211 and the polymerization wafer T (processed wafer W) are rotated, respectively, As shown in 7(b), the first grinding wheel 211 is further moved vertically downward. Then, the first peripheral edge We1 is ground. At this time, the first grinding wheel 211 moves to a predetermined first depth H1 (distance from the processing surface W1 of the processing target wafer W). This first depth H1 is a depth at which the lower surface of the first grinding wheel 211 does not reach the adhesive G.

When grinding the first peripheral portion We1 in this way, since the grain size of the abrasive grain of the first grinding wheel 211 is large, the grinding speed of the first peripheral portion We1 by the first grinding wheel 211 (falling speed) ) Can be increased. As a result, grinding of the first peripheral edge We1 can be performed in a short time.

After that, it is raised while rotating the 1st grinding wheel 211 as shown in FIG. 7(c). At this time, the polymerized wafer T is moved in a horizontal direction so as to be separated from the first grinding wheel 211. Here, when the first grinding wheel 211 is away from the processing target wafer W, that is, when the lower end of the first grinding wheel 211 and the upper end of the processing target wafer W become the same height, the first If the lower end of the grinding wheel 211 and the upper end of the processing target wafer W are in contact with each other, they are caught, and there is a fear that a crack may occur at the top of the processing target wafer W. On the other hand, by moving the polymerized wafer T in the horizontal direction as in this embodiment, when the lower end of the first grinding wheel 211 and the upper end of the processing target wafer W become the same height, they can be separated. , It can suppress the occurrence of cracks.

In this way, in the processing target wafer W, as shown in Fig. 7D, the first peripheral portion We1 in the range of the first width L1 and the first depth H1 is removed, and the first The peripheral edge removal process of is finished (step P1 in Fig. 6).

Subsequently, the superimposed wafer T is conveyed by the wafer conveying device 32 to the second peripheral edge removing device 43. The second peripheral edge removal device 43 also removes the peripheral edge We of the processing target wafer W, but in the following description, the peripheral edge We removed by the second edge removal device 43 is referred to as the second peripheral edge ( There is a case called We2).

The polymerized wafer T conveyed to the second peripheral edge removal device 43 is held by the chuck 220. And, as shown in (e) of FIG. 7, the second grinding wheel 231 is moved vertically downward, while rotating the second grinding wheel 231, the second peripheral edge We2 of the wafer W to be processed. Contact with At this time, the second grinding wheel 231 is such that the range of contact with the processing target wafer W matches the second width L2 in the circumferential direction (distance from the end of the processing target wafer W). Is placed.

Thereafter, in a state in which the second grinding wheel 231 is brought into contact with the second peripheral portion We2, the second grinding wheel 231 and the polymerization wafer T (processed wafer W) are rotated, respectively, as shown in FIG. As shown in 7(f), the second grinding wheel 231 is further moved vertically downward. Then, the second peripheral edge We2 is ground. At this time, the second grinding wheel 231 moves to a predetermined second depth H2 (distance from the processing surface W1 of the processing target wafer W). This second depth H2 is a depth at which the lower surface of the second grinding wheel 231 reaches the bonding surface S1 of the support wafer S. In addition, the second depth H2 can be set arbitrarily. For example, the second depth H2 may be set to the height of the adhesive G, and the bonding surface S1 of the support wafer S may not be cut.

When grinding the second periphery (We2) in this way, since the grain size of the abrasive grain of the second grinding wheel 231 is small, the surface roughness of the finished surface of the ground second periphery (We2) can be reduced, 2 When the peripheral portion We2 is ground, the surface properties and conditions of the surface of the exposed wafer W can be improved. Further, the finish of the exposed side surface We3 of the to-be-processed wafer W is also neat (the surface roughness is small).

Here, the second width L2 of the second peripheral portion We2 to be ground for the second time is smaller than the first width L1 of the first peripheral portion We1 to be ground for the first time. That is, with respect to the peripheral portion We of the processing target wafer W, the second grinding wheel 231 is disposed outside the first grinding wheel 211. And in the outer side in the circumferential direction, the periphery We remain in the range of the depth H2-H1 and the width L1-L2. As described above, since the particle size of the abrasive grains of the second grinding wheel 231 is smaller than the grain size of the abrasive grains of the first grinding wheel 211, the grinding speed by the second grinding stone wheel 231 is the first grinding wheel 211 ) Less than the grinding speed. For this reason, it is more efficient to perform the grinding of the first periphery We1 with the first grinding wheel 211 than with the second grinding wheel 231. In addition, the side surface (hereinafter referred to as the exposed side surface) of the processing target wafer W exposed by the removal of the first peripheral portion We1 is to be ground with the processing device 40 as described later. At the time, they are removed together. For this reason, even if the surface property and condition of the exposed side surface of the processing target wafer W are bad, since they are finally removed, the quality of the processing target wafer W is not affected.

After that, as shown in Fig. 7(g), the second grinding wheel 231 is raised while rotating. At this time, the polymerized wafer T is moved in the horizontal direction so as to be separated from the second grinding wheel 231. As a result, it is possible to suppress the occurrence of cracks in the processing target wafer W, as described with reference to Fig. 7C.

In this way, in the processing target wafer W, as shown in FIG. 7(h), the second peripheral portion We2 in the range of the second width L2 and the second depth H2 is removed, and the second The peripheral edge removal process of is finished (step P2 in Fig. 6).

Subsequently, the superimposed wafer T is conveyed to the processing device 40 by the wafer conveying device 32. The superimposed wafer T conveyed to the processing apparatus 40 is delivered to the alignment unit 120. Then, in the alignment unit 120, the direction in the horizontal direction of the superimposed wafer T is adjusted (step P3 in Fig. 6).

Subsequently, the superimposed wafer T is conveyed from the alignment unit 120 to the delivery position A0 by the conveying unit 110 and transferred to the chuck 101 at the delivery position A0. Thereafter, the rotary table 100 is rotated by 90 degrees counterclockwise to move the chuck 101 to the first machining position A1. Then, the processing surface W1 of the processing target wafer W is roughly ground by the coarse grinding unit 140 (step P4 in Fig. 6).

Then, the rotary table 100 is rotated 90 degrees counterclockwise to move the chuck 101 to the second machining position A2. Then, the processing surface W1 of the processing target wafer W is intermediately ground by the intermediate grinding unit 150 (step P5 in Fig. 6).

Subsequently, the rotary table 100 is rotated 90 degrees counterclockwise, and the chuck 101 is moved to the third machining position A3. Then, the processing surface W1 of the processing target wafer W is finished by the finishing grinding unit 160 (step P6 in Fig. 6). Then, as shown in Fig. 7(i), the processed surface W1 of the processing target wafer W is ground. In addition, the range of the dotted line shown in Fig. 7(i) is a range in which the processing surface W1 of the processing target wafer W is ground by these grinding units 140, 150, 160, and the above-described first peripheral portion The exposed side corresponding to (We1) is also included. Further, the depth at which the processed surface W1 of the processing target wafer W is ground is between the first depth H1 and the second depth H2.

Then, the rotary table 100 is rotated 90 degrees counterclockwise, or the rotary table 100 is rotated 270 degrees clockwise, so that the chuck 101 is moved to the delivery position A0. Here, the processing surface W1 of the processing target wafer W is cleaned by a cleaning liquid discharged from a cleaning liquid nozzle (not shown) (step P7 in Fig. 6).

Subsequently, the superimposed wafer T is transferred from the transfer position A0 to the cleaning unit 130 by the transfer unit 110. And in the cleaning unit 130, while the superimposed wafer T is held on the transfer pad 114, the non-bonding surface S2 of the support wafer S is cleaned and dried (step P8 in FIG. 6). )).

Subsequently, the superimposed wafer T is conveyed to the CMP device 41 by the wafer conveying device 32. In the CMP device 41, the processed surface W1 of the processing target wafer W is polished (defective CMP) by a first polishing unit (not shown), and furthermore, a second polishing unit (not shown) The processing surface W1 of the processing target wafer W is polished (finish CMP) (step P9 in Fig. 6).

Subsequently, the superimposed wafer T is transferred to the first cleaning device 44 by the wafer transfer device 32. The polymerized wafer T conveyed to the first cleaning device 44 is held by the spin chuck 300. Then, while rotating the polymerized wafer T held by the spin chuck 300, the scrub cleaning tool 301 is brought into contact with the processing surface W1 of the processing target wafer W, so that the processing surface W1 is cleaned. (Step (P10) in Fig. 6). The cleaning in this step P10 is to physically remove particles or the like on the processed surface W1, and is rough cleaning.

Subsequently, the polymerized wafer T is conveyed to the second cleaning device 45 by the wafer conveying device 32. The superimposed wafer T conveyed to the second cleaning device 45 is held by the spin chuck 310. Then, while rotating the superimposed wafer T held by the spin chuck 310, a cleaning liquid is supplied from the nozzle to the processing surface W1 of the processing target wafer W, and the processing surface W1 is cleaned (Fig. 6). Of step (P11)). The cleaning in this step P11 is final finishing cleaning.

After that, the superimposed wafer T on which all the processes have been performed is transferred from the wafer transfer device 32 to the wafer transfer device 22 and is transferred to the cassette C of the cassette mounting table 10. In this way, a series of wafer processing in the substrate processing system 1 is ended.

According to the above embodiment, the peripheral portion We of the processing target wafer W is removed in two steps of the step P1 and the step P2. In step P1, since the grain size of the abrasive grains of the first grinding wheel 211 is large, the removal time of the first periphery We1 can be shortened, and the throughput of wafer processing can be improved. Further, in the subsequent step P2, since the grain size of the abrasive grains of the second grinding wheel 231 is small, the surface roughness of the finished surface of the removed second periphery We2 can be reduced. As described above, by using the two grinding wheels 211 and 231 having different particle sizes, the surface of the wafer W exposed by grinding the second periphery We2 while shortening the time according to the removal of the periphery We It can improve the surface properties and condition of.

Further, according to the present embodiment, in one substrate processing system 1, a series of processing can be continuously performed on a plurality of processing target wafers W, and throughput can be improved.

<Whetstone wheel dressing>

In step P2 of the above embodiment, when the second peripheral edge We2 of the processing target wafer W is removed using the second grinding wheel 231, as shown in FIG. 8, the second peripheral edge ( The corner portion N of the bottom of We2) (a portion surrounded by a dotted line in the drawing) may be curved. In this case, after peeling the support wafer S from the processing target wafer W, a curved portion remains on the end face of the processing target wafer W, so that the peripheral portion We of the processing target wafer W is sharply pointed. For this reason, there is a fear that chipping occurs in the peripheral portion We of the processing target wafer W, and the processing target wafer W is damaged.

At this point, for example, in step P2, by controlling the grinding speed by the second grinding wheel 231 or the rotational speed of the second grinding wheel 231, the second peripheral edge We2 shown in FIG. 8 The curvature of the corner part N of can be suppressed to some extent. However, when the second grinding wheel 231 is repeatedly used, the grinding surface of the second grinding wheel 231 is worn, and the corner portion N of the second peripheral edge We2 is liable to bend.

Therefore, it is preferable to perform so-called dressing for adjusting the grinding surface of the second grinding wheel 231. In the dressing of the 2nd grinding wheel 231, as shown in FIGS. 1 and 9, the dress board 400 as an adjustment part is used. The dress board 400 has a circular shape when viewed from the top, and has a stepped portion 401 at its periphery.

The dress board 400 is provided, for example, on the X-axis positive side of the second peripheral edge removal unit 230 in the interior of the second edge removal device 43. On the lower surface side of the dress board 400, a movement mechanism 410 which moves and rotates the dress board 400 in the horizontal and vertical directions is provided. The moving mechanism 410 has, for example, a shaft 411, two arms 412 and 413, and a drive unit 414. The shaft 411 is provided between the lower surface of the dress board 400 and the tip end of the first arm 412. A rotating part (not shown) is provided at the distal end of the first arm 412, and the dress board 400 is rotatable through the shaft 411 by this rotating part. The first arm 412 and the second arm 413 are connected by a joint portion (not shown), and by this joint portion, the first arm 412 is configured to be pivotable around the base end portion. The second arm 413 is mounted on the driving unit 414, and by the driving unit 414, the second arm 413 is configured to be able to pivot around the base end and to move in the vertical direction. In addition, the dress board 400 can move forward and backward with respect to the second peripheral edge removal unit 230 by the moving mechanism 410 having such a configuration.

Further, the dress board 400 is not limited to the inside of the second peripheral edge removal device 43 described above, and can be installed at any position. For example, the dress board 400 is disposed outside the second peripheral edge removal device 43, for example, in an installation place (not shown) such as a shelf, and is held in the chuck 200 You may do dressing.

In this case, while rotating each of the second grinding wheel 231 and the dress board 400, the step portion 401 of the dress board 400 is brought into contact with the periphery of the second grinding wheel 231. Then, in the peripheral portion of the second grinding wheel 231, the lower surface 231a and the outer surface 231b (the grinding surface of the second peripheral portion We2) are respectively ground and flattened. That is, in the second grinding wheel 231, the lower end that contacts the corner portion N of the second peripheral edge We2 shown in FIG. 8 is at a right angle. And, by grinding the second periphery (We2) using the second grinding wheel 231 dressing in this way, the corner portion (N) of the second periphery (We2) can be formed at a right angle, resulting in curvature. Can be suppressed.

In addition, in the dressing of the second grinding wheel 231, in advance, using, for example, a laser displacement meter, the surfaces of the lower surface 231a and the outer surface 231b at the periphery of the second grinding wheel 231 You can check the condition. Specifically, for example, the height of the lower surface 231a and the outer surface 231b is measured. Further, as a result of the inspection, when abrasion or abnormal protrusions or the like are found on one or both of the lower surface 231a and the outer surface 231b, dressing of the second grinding wheel 231 may be performed.

In addition, from the viewpoint of suppressing the curvature of the corner portion N of the second peripheral portion We2, the second grinding wheel 231 may have a tapered shape when viewed from the side. The diameter of the lower surface of the second grinding wheel 231 is made larger than the diameter of the upper surface, that is, the lower surface protrudes outward. In this case, even if the second grinding wheel 231 is worn, the lower end of the second grinding wheel 231 becomes an acute angle when viewed from the side, and the corner portion N of the second peripheral portion We2 becomes difficult to bend. .

In addition, in the above-described example, the dressing of the second grinding wheel 231 has been described, but it is preferable to perform dressing for the first grinding wheel 211 using the same dress board 400.

<Other embodiment>

The configuration of the substrate processing system 1 is not limited to the above embodiment. For example, in the substrate processing system 1 of the above embodiment, the second peripheral edge removal unit 230 was provided in the second peripheral edge removal apparatus 43 outside the processing apparatus 40, but as shown in FIG. It may be provided inside the processing device 40. In this case, the second peripheral edge removal unit 230 is disposed at the first machining position (A1), the second machining position (A2) and the third machining position (A3), respectively, a rough grinding unit 140 and a finish grinding unit 160 is placed. Further, in this case, the intermediate grinding unit 150 is omitted.

The first peripheral edge removal device 42 removes the first peripheral edge We1 of the processing target wafer W, but the range (the first width L1 and the first depth H1) is usually large. For this reason, even if the first grinding wheel 211 having a large particle size is used, it may take some time to remove the first periphery We1.

On the other hand, the range (the second width L2 and the second depth H2) of the second peripheral portion We2 removed by the second peripheral edge removing device 43 is usually small. For this reason, even if the 2nd peripheral edge removal part 230 is provided inside the processing apparatus 40, the throughput in the processing apparatus 40 is not reduced. Therefore, as in the present embodiment, by providing the second peripheral edge removal unit 230 inside the processing apparatus 40, it is also possible to improve the throughput of the entire wafer processing.

Further, in the substrate processing system 1 of the above embodiment, the processing apparatus 40, the CMP apparatus 41, the first lead removal apparatus 42, the second lead removal apparatus 43, and the first cleaning apparatus 44 ), the number and arrangement of the second cleaning devices 45 can be arbitrarily designed.

In the substrate processing system 1 of the above embodiment, the first peripheral edge removal portion 210 and the second edge removal portion 230 were provided separately, but they may be combined. For example, with respect to a common support wheel (not shown), the first grinding wheel 211 and the second grinding wheel 231 are double-mounted in a concentric circle shape. For example, when the diameter of the first grinding wheel 211 is increased and the diameter of the second grinding wheel 231 is decreased, the second grinding wheel 231 is disposed inside the first grinding wheel 211.

In this case, in the inside of one peripheral edge removal device, the peripheral edge We of the processing target wafer W is removed in two steps by using the two first edge removal units 210 and the second edge removal units 230. Can be removed. Therefore, the throughput of wafer processing can be improved.

In the substrate processing system 1 of the above embodiment, the processing target wafer W and the support wafer S were joined via an adhesive G, but instead of the adhesive G, a double-sided tape was used. The processing target wafer W and the support wafer S may be bonded together.

As mentioned above, although the embodiment of this invention was demonstrated, this invention is not limited to this example. It is clear to those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea described in the claims, and they are naturally understood to belong to the technical scope of the present invention.

1: substrate processing system
2: carry-in and carry-out station
3: processing station
40: processing device
41: CMP device
42: first main smoke removal device
43: second main smoke removal device
50: control unit
140: coarse grinding unit
141: rough grinding part
150: intermediate grinding unit
151: intermediate grinding part
160: finish grinding unit
161: finish grinding part
200: chuck
201: chuck table
202: return route
210: first main edge removal unit
211: first grinding wheel
212: support wheel
213: spindle
214: drive unit
215: lifting mechanism
220: chuck
221: chuck table
222: return route
230: second main edge removal unit
231: 2nd whetstone wheel
232: support wheel
233: spindle
234: drive unit
235: lifting mechanism
400: dress board
G: adhesive
S: support wafer
T: polymerization wafer
W: wafer to be processed
W1: Machined surface
W2: Non-processed surface
We(We1, We2): The main part (the 1st main part, the 2nd main part)

Claims (17)

As a substrate processing system for processing a substrate,
A first peripheral edge removal portion having a first grindstone in contact with a peripheral portion of the substrate, and grinding and removing the peripheral edge portion to a first depth;
A second edge removal having a second grindstone in contact with the periphery of the substrate, and after removing the periphery by the first periphery removing portion, further grinding the periphery to a second depth deeper than the first depth to remove Have wealth,
The substrate processing system, wherein the particle size of the abrasive grains provided by the second grinding stone is smaller than the grain size of the abrasive grains provided by the first grinding stone. The method of claim 1,
After removing the peripheral portion by the second peripheral edge removing portion, the substrate processing system having a grinding portion for grinding the processed surface of the substrate to a distance between the first depth and the second depth. The method of claim 1,
A substrate processing system, wherein a device is formed on a non-processed surface of the substrate before the peripheral edge is removed by the first peripheral edge removal unit, and a protective material for protecting the device is provided. The method of claim 1,
A substrate processing system, wherein a grinding speed of the peripheral portion by the second peripheral edge removal portion is lower than a grinding speed of the peripheral portion by the first peripheral edge removal portion. The method of claim 1,
The substrate processing system, wherein a width in the circumferential direction of the peripheral portion removed by the second peripheral edge removal portion is smaller than a width in the circumferential direction of the peripheral portion removed by the first peripheral edge removal portion. The method of claim 1,
A substrate holding portion for holding the substrate when the peripheral portion is removed from the first peripheral edge removing portion,
A lifting mechanism for lifting the first grinding stone,
A substrate processing system having a moving mechanism for moving the first grindstone and the substrate holding portion in a relatively horizontal direction. The method of claim 1,
A substrate holding portion for holding the substrate when the peripheral portion is removed from the second peripheral edge removing portion,
A lifting mechanism for lifting the second grinding wheel,
A substrate processing system having a moving mechanism for moving the second grindstone and the substrate holding portion in a relatively horizontal direction. The method of claim 1,
A substrate processing system having an adjustment unit for adjusting the grinding surface of the first grinding stone or the grinding surface of the second grinding stone. A substrate processing method for processing a substrate,
A first peripheral edge removal step of bringing a first grindstone into contact with a peripheral edge of the substrate and grinding and removing the peripheral edge to a first depth,
Thereafter, having a second peripheral edge removal step of bringing a second grindstone into contact with the peripheral portion of the substrate and grinding and removing the peripheral edge portion to a second depth deeper than the first depth,
The substrate processing method, wherein the particle size of the abrasive grains provided by the second grinding stone is smaller than the grain size of the abrasive grains provided by the first grinding stone. The method of claim 9,
After the second peripheral edge removal step, a substrate processing method comprising a grinding step of grinding the processed surface of the substrate to a distance between the first depth and the second depth. The method of claim 9,
A substrate processing method, wherein a device is formed on an unprocessed surface of the substrate before the first peripheral edge removal step, and a protective material for protecting the device is provided. The method of claim 9,
The substrate processing method, wherein a grinding speed of the peripheral portion in the second peripheral edge removal step is smaller than a grinding speed of the peripheral edge portion in the first peripheral edge removal step. The method of claim 9,
A substrate processing method, wherein a width of the peripheral portion removed in the second peripheral edge removal step in the circumferential direction is smaller than a width of the peripheral edge portion removed in the first peripheral edge removal process. The method of claim 9,
In the first main smoke removal process,
In a state in which the first grinding stone is brought into contact with the peripheral edge of the substrate held in the substrate holding portion, the first grinding stone is lowered to grind the peripheral edge to the first depth,
Thereafter, the first grinding wheel is raised, and the first grinding stone and the substrate holding portion are moved in a relatively horizontal direction to separate them apart. The method of claim 9,
In the second main smoke removal process,
In a state in which the second grinding stone is brought into contact with the peripheral edge of the substrate held in the substrate holding portion, the second grinding stone is lowered to grind the peripheral edge to the second depth,
Thereafter, the second grinding stone is raised, and the second grinding stone and the substrate holding portion are moved in a relatively horizontal direction to be separated from each other. The method of claim 9,
A substrate processing method comprising an adjustment step of adjusting the grinding surface of the first grinding stone or the grinding surface of the second grinding stone. A readable computer storing a program running on a computer of a control unit controlling the substrate processing system to execute a substrate processing method for processing a substrate by a substrate processing system,
The substrate processing method,
A first peripheral edge removal step of bringing a first grindstone into contact with a peripheral edge of the substrate and grinding and removing the peripheral edge to a first depth,
Thereafter, having a second peripheral edge removal step of bringing a second grindstone into contact with the peripheral portion of the substrate and grinding and removing the peripheral edge portion to a second depth deeper than the first depth,
The computer storage medium, wherein the particle size of the abrasive grains provided by the second grinding stone is smaller than the grain size of the abrasive grains provided by the first grinding stone.

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