KR102607483B1 - Substrate processing system, substrate processing method, and computer storage medium - Google Patents

Abstract

A substrate processing system for processing a substrate includes a first grindstone that contacts the peripheral portion of the substrate, a first peripheral removal portion that grinds and removes the peripheral portion to a first depth, and a second peripheral portion that contacts the peripheral portion of the substrate. It has a grindstone, and after removing the peripheral part by the first edge removal part, it has a second edge removal part that further grinds and removes the peripheral part to a second depth deeper than the first depth, and is provided with the second edge removal part. The particle size of the abrasive grains is smaller than the particle size of the abrasive grains included in the first grindstone.

Description

Substrate processing system, substrate processing method, and computer storage medium

This application claims priority based on Patent Application No. 2017-243303 filed in Japan on December 19, 2017, the contents of which are incorporated herein by reference.

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.

Recently, in the semiconductor device manufacturing process, the back side of a semiconductor wafer (hereinafter referred to as “wafer”) on which a plurality of devices such as electronic circuits are formed on the surface is ground and polished to thin the wafer. It is being done. And, if this thinned wafer is transported as is or subjected to subsequent processing, there is a risk that the wafer may be warped or cracked. For this reason, in order to reinforce the wafer, for example, attaching the wafer to a support substrate is performed.

However, the peripheral portion of the wafer is usually chamfered, but when the wafer is subjected to grinding and polishing processing as described above, the peripheral portion of the wafer becomes sharply pointed. Then, there is a risk that chipping may occur at the periphery of the wafer, causing damage to the wafer. Therefore, so-called edge trimming, which is to shave the peripheral portion of the wafer in advance before the grinding process, is performed.

For example, Patent Document 1 discloses a vertical axis-type surface grinding device as a device for edge trimming. When grinding the peripheral portion of a wafer using this longitudinal axis type surface grinding device, the wafer is first fixed to a table, and the table is rotated around an axis parallel to the vertical axis. Then, the spindle is rotated to provide rotation to the cup wheel, and then 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 portion of the wafer.

Japanese Patent Laid-open Publication No. 09-216152

As described above, in the plane grinding device described in Patent Document 1, the peripheral portion of the wafer is ground using a cup wheel. Here, for example, if the grinding speed of the peripheral part is to be increased, it is necessary to increase the grain size of the abrasive grains of the cup wheel. However, in this case, the surface of the wafer exposed by grinding the peripheral portion (hereinafter referred to as 'exposed surface') becomes rough, and there are cases where the specified quality cannot be satisfied.

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

The present invention was made in consideration of the above circumstances, and the purpose of the present invention is to shorten the time taken to remove the peripheral portion by grinding and removing the peripheral portion of the substrate, and to improve the surface properties and condition of the substrate surface exposed by grinding the peripheral portion. .

One aspect of the present invention that solves the above problem is a substrate processing system for processing a substrate, including a first grindstone in contact with a peripheral portion of the substrate, and a first peripheral grinding wheel for grinding and removing the peripheral portion to a first depth. A second grinding wheel that is in contact with the peripheral portion of the substrate, and which removes the peripheral portion by further grinding the peripheral portion to a second depth deeper than the first depth after removing the peripheral portion by the first periphery removal unit. It has two peripheral removal parts, and the particle size of the abrasive grains included in the second grindstone is smaller than the particle size of the abrasive grains included in the first grindstone.

One aspect of the present invention according to another aspect is a substrate processing method for processing a substrate, comprising: a first periphery removal step of contacting a peripheral portion of the substrate with a first grindstone to grind and remove the peripheral portion to a first depth; Thereafter, a second peripheral removal process is performed in which a second grindstone is brought into contact with the peripheral portion of the substrate, and the peripheral portion is removed by grinding to a second depth deeper than the first depth, wherein the particle size of the abrasive grains provided by the second grindstone is is smaller than the particle size of the abrasive grains provided in the first grindstone.

According to one aspect of the present invention according to another aspect, it is a readable computer storage medium storing a program that runs on a computer of a control unit that controls the substrate processing system to execute the substrate processing method by the substrate processing system.

According to one aspect of the present invention, when grinding and removing the peripheral portion of a substrate, the time taken to remove the peripheral portion can be shortened by using the first grindstone, thereby improving the throughput of substrate processing. Additionally, by using the second grindstone, it is possible to improve the surface properties and condition of the substrate surface exposed by grinding the peripheral portion.

1 is a plan view schematically showing the outline of the configuration of a substrate processing system according to this embodiment.
Figure 2 is a side view schematically showing the structure of a polymerization wafer.
Figure 3 is a plan view schematically showing the structure of the processing device.
Fig. 4 is a side view schematically showing the configuration of the first periphery removal unit (second periphery removal unit).
Fig. 5 is an explanatory diagram schematically showing the configuration of the first edge removal unit (second edge removal unit).
Figure 6 is a flowchart showing the main processes of wafer processing.
Figure 7 is an explanatory diagram showing how the wafer to be processed is ground in the main process of wafer processing.
FIG. 8 is an explanatory diagram showing how the corner portion of the bottom of the second peripheral portion is curved when the second peripheral portion of the wafer to be processed is removed.
Fig. 9 is an explanatory diagram showing how the grinding surface of the second grindstone wheel is adjusted with a dress board.
Figure 10 is a plan view schematically showing the outline of the configuration of a substrate processing system according to another embodiment.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention will be described with reference to the drawings. Additionally, in this specification and drawings, elements having substantially the same functional structure are assigned the same reference numerals to omit duplicate descriptions.

<Substrate processing system>

First, the configuration of the substrate processing system according to this embodiment will be described. 1 is a plan view schematically showing the outline of the configuration of the substrate processing system 1. In addition, in the following, in order to clarify the positional relationship, the

In the substrate processing system 1 of the present embodiment, as shown in FIG. 2, a polymerized wafer (T) in which a processing wafer (W) as a substrate and a support wafer (S) are bonded, for example, via an adhesive (G). ) is processed, and the processed wafer (W) is thinned. Hereinafter, in the wafer to be processed (W), the surface to be processed (ground) (the surface opposite to the surface to which the adhesive G is attached) is referred to as 'processed surface (W1)', and the surface on the opposite side to the processed surface (W1) is referred to as 'processed surface (W1)'. The surface is called the ‘unprocessed surface (W2)’. In addition, in the support wafer S, the surface bonded to the processing wafer W via the adhesive G is referred to as the 'bonded surface S1', and the surface opposite to the bonded surface S1 is referred to as the 'non-bonded surface. It is called ‘side (S2)’. Additionally, in this embodiment, the processing wafer W and the support wafer S are bonded via the adhesive G, but the bonding method is not limited to this.

The processing 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. Additionally, the peripheral portion of the wafer to be processed W is chamfered, and the thickness of the cross-section of the peripheral portion decreases toward the tip.

The support wafer S is a wafer that supports the processing wafer W. Additionally, the support wafer S, together with the adhesive G, functions as a protective material that protects the devices on the unprocessed surface W2 of the wafer to be processed W. In addition, in this embodiment, the case where a wafer is used as the support substrate is explained, but other substrates such as, for example, a glass substrate may be used.

As shown in FIG. 1, the substrate processing system 1 includes, for example, a loading and unloading station 2 into which a cassette C capable of holding a plurality of polymerized wafers T is loaded and unloaded between the outside and the polymerized wafer T. It has a configuration in which a processing station 3 equipped with various processing devices that performs specified processing on (T) is connected.

The loading/unloading station (2) is provided with a cassette placement table (10). In the example shown, a plurality of, for example, four cassettes C can be placed in a row on the cassette placement table 10 in the X-axis direction.

The loading/unloading station 2 is provided with a wafer transfer area 20 adjacent to the cassette placement 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 for holding and transferring the polymerized wafer T. Each transfer arm 23 is configured to be movable in the horizontal direction, vertical direction, around the horizontal axis, and around the vertical axis. Additionally, the configuration of the transfer arm 23 is not limited to this embodiment and can have any configuration.

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 for holding and transferring the polymerized wafer T. Each transfer arm 33 is configured to be movable in the horizontal direction, vertical direction, around the horizontal axis, and around the vertical axis. Additionally, the configuration of the transfer arm 33 is not limited to this embodiment and can have any configuration.

In the processing station 3, around the wafer transfer area 30, a processing device 40, a CMP device 41 (CMP: Chemical Mechanical Polishing), a first edge removal device 42, A second edge removal device 43, a first cleaning device 44, and a second cleaning device 45 are provided. On the negative On the positive X-axis direction side of the wafer transfer area 30, the first edge removal device 42 and the second edge removal device 43 are arranged in an array from the Y-axis positive direction toward the negative direction. Above the wafer transfer area 30, on the negative Y-axis direction side, the first cleaning device 44 and the second cleaning device 45 are arranged and arranged from the positive Y-axis direction toward the negative direction. Additionally, below the second cleaning device 45, a transition device (not shown) is provided for transferring the polymerized wafer T between the wafer transfer device 22 and the wafer transfer device 32.

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 that controls processing of the polymerized 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 the drive systems of the various processing devices or transfer devices described above to realize the later-described wafer processing in the substrate processing system 1. In addition, the program can be stored on a computer-readable storage medium (H) such as a computer-readable hard disk (HD), flexible disk (FD), compact disk (CD), magnet optical disk (MO), or memory card. It may be something that has been recorded or installed into the control unit 50 from the storage medium (H).

(processing equipment)

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

The rotary table 100 is configured to be rotatable by a rotary mechanism (not shown). On the rotary table 100, four chucks 101 are provided to adsorb and hold the polymerized wafer T. The chuck 101 is arranged evenly, that is, at intervals of 90 degrees, on the same circumference as the rotary table 100. The four chucks 101 can be moved to the delivery 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 on the 130 is placed. The first machining position A1 is a position on the X-axis positive direction side and the Y-axis positive direction side of the rotary table 100, and the rough grinding unit 140 is disposed. The second machining position A2 is a position on the X-axis negative direction side and the Y-axis positive direction side of the rotary table 100, and the intermediate grinding unit 150 is disposed. The third machining position A3 is a position on the negative X-axis direction side and the Y-axis negative direction side of the rotary table 100, and the finish grinding unit 160 is disposed.

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 an articulated robot with a plurality of arms, 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 able to rotate about the proximal end. . Among the three arms 111 to 113, the first arm 111 at the tip is equipped with a transfer pad 114 for adsorbing and holding the polymerized wafer T. Additionally, among the three arms 111 to 113, the third arm 113 at the base is attached to a vertical movement mechanism 115 that moves the arms 111 to 113 in the vertical direction. And, the transfer unit 110 equipped with this configuration can transfer the polymerized wafer T to the transfer position A0, the alignment unit 120, and the cleaning unit 130.

The alignment unit 120 adjusts the horizontal direction of the polymerized wafer T before the grinding process. For example, by rotating the polymerization wafer T held in a spin chuck (not shown) and 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. Adjust the horizontal direction of the wafer (T).

In the cleaning unit 130, the non-bonded surface S2 of the support wafer S with the polished polymerized wafer T held on the transport pad 114 is cleaned, and the transport pad 114 is also cleaned. do.

In the rough grinding unit 140, the processing surface W1 of the wafer to be processed W is roughly ground. The rough grinding unit 140 has a rough grinding unit 141 equipped with a rough grinding wheel (not shown) that can rotate in an annular shape. In addition, the rough grinding portion 141 is configured to be movable in the vertical and horizontal directions along the support column 142. Then, while the processing wafer W held in the chuck 101 is brought into contact with the rough grinding wheel, the chuck 101 and the rough grinding wheel are each rotated to grind the processing surface W1 of the processing wafer W. Rough grinding.

In the intermediate grinding unit 150, the processing surface W1 of the wafer to be processed W is intermediately ground. The intermediate grinding unit 150 has an intermediate grinding unit 151 equipped with an intermediate grinding wheel (not shown) rotatable in an annular shape. In addition, the intermediate grinding portion 151 is configured to be movable in the vertical and horizontal directions along the support column 152. Additionally, the grain size of the abrasive grains of the intermediate grinding wheel is smaller than that of the coarse grinding wheel. Then, with the processing surface W1 of the wafer W held in the chuck 101 in contact with the intermediate grinding wheel, the processing surface W1 is ground by rotating the chuck 101 and the intermediate grinding wheel, respectively. Grinding.

The final grinding unit 160 performs final grinding on the processing surface W1 of the wafer to be processed W. The finishing grinding unit 160 has a finishing grinding unit 161 provided with a finishing grinding wheel (not shown) that can rotate in an annular shape. Additionally, the finish grinding unit 161 is configured to be movable in the vertical and horizontal directions along the support column 162. Additionally, the grain size of the abrasive grains of the finishing grinding wheel is smaller than that of the intermediate grinding wheel. Then, while the processing surface W1 of the wafer W held in the chuck 101 is brought into contact with the finishing grinding wheel, the processing surface W1 is finished by rotating the chuck 101 and the finishing grinding wheel, respectively. Grinding.

(CMP device)

The CMP device 41 shown in FIG. 1 is provided with, for example, two polishing units (not shown) for polishing the processing surface W1 of the wafer W to be processed. The particle size of the abrasive grains used in the first polishing section is larger than that of the abrasive grains used in the second polishing section. Then, the machined surface W1 is roughly polished in the first polishing section, and the machined surface W1 is finished polished in the second polishing section. Additionally, the configuration of the CMP device 41 can be a general configuration that performs chemical polishing. For example, processing may be performed in a so-called face-up state with the processing surface W1 of the wafer to be processed facing upward, or processing may be performed in a so-called face-down state with the processing surface W1 facing downward. You can do it.

(main cast removal device)

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

The first periphery removal device 42 has a chuck 200 as a substrate holding portion that holds the polymerized wafer T (processed wafer W). The chuck 200 is supported on the chuck table 201 and is configured to be movable on the conveyance path 202 extending in the X-axis direction. Additionally, the chuck 200 is configured to be rotatable by a rotation mechanism (not shown). Additionally, in this embodiment, the chuck table 201 and the conveyance path 202 constitute the moving mechanism of the present invention. In addition, the moving mechanism of the present invention can move the chuck 200 and the first grindstone wheel 211, which will be described later, in a relatively horizontal direction, and the first grindstone wheel 211 may be moved in the horizontal direction, or the chuck ( Both 200) and the first grindstone wheel 211 may be moved in the horizontal direction.

Additionally, the first periphery removal device 42 has a first periphery removal unit 210 disposed above the chuck 200 and removing the periphery of the wafer to be processed W held in the chuck 200. . As shown in FIG. 4 , the first edge removal unit 210 has a first grinding wheel 211, a support wheel 212, a spindle 213, and a drive unit 214.

The support wheel 212 that fixes the first grindstone wheel 211 is supported on the spindle flange 213a of the spindle 213, and the spindle 213 is provided with a drive unit 214. The drive unit 214 includes, for example, a motor (not shown) and rotates the first grindstone wheel 211 and the support wheel 212 via the spindle 213. Additionally, the spindle 213 and the drive unit 214 are configured to be capable of being raised and lowered by a lifting mechanism 215.

As shown in Fig. 5, the first 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 portion We of the wafer W to be processed, and grinds and removes the peripheral portion We. In addition, in this embodiment, the first grindstone wheel 211 is provided in an annular shape, but it is not limited to this, and may be provided in segments along the support wheel 212, for example.

In the first periphery removal device 42, the wafer to be processed W is first moved in the horizontal direction so that the range where the first grinding wheel 211 contacts the wafer to be processed W has a predetermined width. Arrange the first grindstone wheel 211 so that it matches.

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 wafer W, the first grinding wheel 211 and the polymerized wafer T (processing wafer W) The peripheral portion (We) is ground and removed by rotating each. Also, at this time, by moving the first grindstone wheel 211 vertically downward from the state in which the first grindstone wheel 211 is brought into contact with the processing surface W1 of the wafer to be processed, the peripheral portion We is Remove by grinding from top to bottom.

Additionally, the second edge removal device 43 also 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 (second grinding wheel). (231), support wheel 232, spindle 233, drive unit 234, and lifting mechanism 235). However, the particle size of the abrasive grains of the second grinding wheel 231 is smaller than that of the first grinding wheel 211.

(Cleaning device)

As shown in FIG. 1, the first cleaning device 44 rough cleans the processing surface W1 of the processing target wafer W, and the second cleaning device 45 cleans the processing surface W1 of the processing target wafer W. ) is finally cleaned.

The first cleaning device 44 has a spin chuck 300 that holds and rotates the polymerized wafer T, and a scrub cleaning tool 301 equipped with, for example, a brush. Then, while rotating the polymerized wafer T held in the spin chuck 300, the scrub cleaning tool 301 is brought into contact with the processing surface W1 of the processing target wafer W, thereby cleaning the processing surface W1. .

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, for example, pure water, to the processing surface W1 of the wafer to be processed W. ) has. Then, while rotating the polymerized wafer T held in the spin chuck 310, the cleaning liquid is supplied from the nozzle 311 to the processing surface W1 of the wafer to be processed W. Then, the supplied cleaning liquid spreads on the machined surface W1, and the machined surface W1 is cleaned.

<Wafer processing>

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

First, a cassette (C) containing a plurality of polymerized wafers (T) is placed on the cassette placement table 10 of the loading/unloading station 2. The polymerized wafer T is stored in the cassette C so that the processing surface W1 of the processing wafer W faces upward.

Next, 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). , is conveyed to the first edge removal device 42 of the processing station 3. In the first periphery removal device 42, the peripheral portion We of the wafer to be processed is removed. In the following description, the peripheral portion We removed by the first peripheral removal device 42 is referred to as the first peripheral portion. There is a case called (We1).

The polymerized wafer T transported to the first periphery removal device 42 is held in the chuck 200 . Then, as shown in (a) of FIG. 7, the first grinding wheel 211 is moved vertically downward, and the first peripheral portion We1 of the wafer to be processed W is rotated while rotating the first grinding wheel 211. contact with. At this time, the range of the first grindstone wheel 211 in contact with the wafer to be processed W is the first width L1 in the predetermined circumferential direction (distance from the end of the wafer to be processed W). ) is arranged to match.

Afterwards, with the first grindstone wheel 211 in contact with the first peripheral portion We1, the first grindstone wheel 211 and the polymerization wafer T (processed wafer W) are rotated, respectively, as shown in FIG. As shown in (b) of 7, the first grindstone wheel 211 is further moved vertically downward. Then, the first peripheral portion We1 is ground. At this time, the first grindstone wheel 211 moves to a predetermined first depth H1 (distance from the processing surface W1 of the wafer to be processed W1). This first depth H1 is a depth at which the lower surface of the first grindstone 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 grains of the first grinding wheel 211 is large, the grinding speed (lowering speed) of the first peripheral portion We1 by the first grinding wheel 211 ) can be increased. As a result, grinding of the first peripheral portion We1 can be performed in a short time.

Afterwards, as shown in (c) of FIG. 7, the first grindstone wheel 211 is raised while rotating. At this time, the polymerized wafer T is moved in the horizontal direction so as to be separated from the first grinding wheel 211. Here, when the first grinding wheel 211 moves away from the wafer to be processed (W), that is, when the lower end of the first grinding wheel 211 and the upper end of the wafer to be processed (W) become the same height, the first grinding wheel 211 moves away from the wafer to be processed (W). If the lower end of the grindstone wheel 211 and the upper end of the wafer W are in contact, there is a risk that they may become caught and cracks may occur in the upper end of the wafer W. In contrast, by moving the polymerized wafer T in the horizontal direction as in the present embodiment, when the lower end of the first grinding wheel 211 and the upper end of the wafer to be processed W are at the same height, they can be separated. , the occurrence of cracks can be suppressed.

In this way, as shown in (d) of FIG. 7, in the wafer W to be processed, the first peripheral portion We1 in the range of the first width L1 and the first depth H1 is removed, The peripheral part removal process ends (step (P1) in FIG. 6).

Next, the polymerized wafer T is transported to the second periphery removal device 43 by the wafer transport device 32. The second periphery removal device 43 also removes the peripheral portion We of the wafer W to be processed. In the following description, the peripheral portion We removed by the second peripheral removal device 43 is referred to as the second peripheral portion ( There is a case called We2).

The polymerized wafer T conveyed to the second periphery removal device 43 is held in the chuck 220 . Then, as shown in (e) of FIG. 7, the second grinding wheel 231 is moved vertically downward, and the second peripheral portion We2 of the wafer to be processed W is rotated while rotating the second grinding wheel 231. contact with. At this time, the second grinding wheel 231 is adjusted such that the contact area with the processing wafer W coincides with the predetermined second width L2 (distance from the end of the processing wafer W) in the predetermined circumferential direction. It is placed.

Thereafter, with the second grindstone wheel 231 in contact with the second peripheral portion We2, the second grindstone wheel 231 and the polymerization wafer T (processed wafer W) are rotated, respectively, as shown in FIG. As shown in (f) of 7, the second grindstone wheel 231 is further moved vertically downward. Then, the second peripheral portion We2 is ground. At this time, the second grindstone wheel 231 moves to a predetermined second depth H2 (distance from the processing surface W1 of the wafer to be processed W1). This second depth H2 is the depth at which the lower surface of the second grinding wheel 231 reaches the bonding surface S1 of the support wafer S. Additionally, 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 peripheral portion We2 in this way, 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 ground second peripheral portion We2 can be reduced, 2 By grinding the peripheral portion We2, the surface properties and condition of the surface of the exposed wafer W can be improved. In addition, the exposed side surface We3 of the wafer W is neatly finished (the surface roughness is small).

Here, the second width L2 of the second peripheral portion We2 to be ground second is smaller than the first width L1 of the first peripheral portion We1 to be ground first. That is, the second grindstone wheel 231 is disposed outside the first grindstone wheel 211 with respect to the peripheral portion We of the wafer to be processed (W). And on the outer side in the circumferential direction, the peripheral portion We remains as much as the range of depth (H2-H1) and width (L1-L2). As described above, since the particle size of the abrasive grains of the second grinding wheel 231 is smaller than that of the first grinding wheel 211, the grinding speed by the second grinding wheel 231 is lower than that of the first grinding wheel 211. ) is smaller than the grinding speed due to For this reason, grinding of the first peripheral portion We1 with the first grinding wheel 211 is more efficient than grinding with the second grinding wheel 231. In addition, the side surface of the wafer W to be processed (hereinafter referred to as the exposed side) exposed by removing the first peripheral portion We1 can be processed by grinding the processing surface W1 with the processing device 40, as described later. Upon completion, they are removed together. For this reason, even if the surface properties and condition of the exposed side of the to-be-processed wafer W are poor, the quality of the to-be-processed wafer W is not affected because it is ultimately removed.

Afterwards, as shown in (g) of FIG. 7, the second grindstone wheel 231 is rotated and raised. 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, as explained using (c) of FIG. 7, the occurrence of cracks in the wafer W to be processed can be suppressed.

In this way, as shown in (h) of FIG. 7, in the wafer W to be processed, the second peripheral portion We2 in the range of the second width L2 and the second depth H2 is removed, and the second peripheral portion We2 is removed. The peripheral part removal process ends (step (P2) in FIG. 6).

Next, the polymerized wafer T is transported to the processing device 40 by the wafer transport device 32. The polymerized wafer T transported to the processing device 40 is delivered to the alignment unit 120. Then, in the alignment unit 120, the horizontal direction of the polymerized wafer T is adjusted (step P3 in FIG. 6).

Next, the polymerized wafer T is transported from the alignment unit 120 to the transfer position A0 by the transport unit 110, and is transferred to the chuck 101 at the transfer position A0. Afterwards, the rotary table 100 is rotated 90 degrees counterclockwise to move the chuck 101 to the first machining position A1. Then, the processing surface W1 of the processing wafer W is coarsely ground by the rough grinding unit 140 (step P4 in FIG. 6).

Next, 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 wafer W is intermediately ground by the intermediate grinding unit 150 (step P5 in FIG. 6).

Next, the rotary table 100 is rotated 90 degrees counterclockwise to move the chuck 101 to the third machining position A3. Then, the machining surface W1 of the wafer to be processed W is subjected to final grinding by the final grinding unit 160 (step P6 in FIG. 6 ). Then, as shown in FIG. 7(i), the processing surface W1 of the processing target wafer W is ground. In addition, the range of the dotted line shown in (i) of FIG. 7 is the range in which the processing surface W1 of the wafer to be processed W is ground by these grinding units 140, 150, and 160, and the above-mentioned first peripheral portion The exposure aspect corresponding to (We1) is also included. Additionally, the depth at which the processing surface W1 of the wafer to be processed W is ground is between the first depth H1 and the second depth H2.

Next, the rotary table 100 is rotated 90 degrees counterclockwise, or the rotary table 100 is rotated 270 degrees clockwise, and the chuck 101 is moved to the delivery position A0. Here, the processing surface W1 of the wafer to be processed W is cleaned with a cleaning liquid discharged from a cleaning liquid nozzle (not shown) (step P7 in FIG. 6).

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

Next, the polymerized wafer T is transported to the CMP apparatus 41 by the wafer transport device 32. In the CMP device 41, the processing surface W1 of the wafer W to be processed is polished (defect CMP) by a first polishing unit (not shown), and further polished by a second polishing unit (not shown). The processing surface W1 of the wafer to be processed W is polished (finish CMP) (step P9 in FIG. 6).

Next, the polymerized wafer T is transferred to the first cleaning device 44 by the wafer transfer device 32. The polymerized wafer T transported to the first cleaning device 44 is held in the spin chuck 300. Then, while rotating the polymerized wafer T held in the spin chuck 300, the scrub cleaning tool 301 is brought into contact with the processing surface W1 of the processing wafer W, and the processing surface W1 is cleaned. (Step (P10) in Figure 6). The cleaning in this step (P10) physically removes particles, etc. on the processing surface W1 and is rough cleaning.

Next, the polymerized wafer T is transferred to the second cleaning device 45 by the wafer transfer device 32 . The polymerized wafer T transported to the second cleaning device 45 is held in the spin chuck 310 . Then, while rotating the polymerized wafer T held in the spin chuck 310, the cleaning liquid is supplied from the nozzle to the processing surface W1 of the processing wafer W, and the processing surface W1 is cleaned (FIG. 6 Step (P11)). The cleaning in this step (P11) is the final finishing cleaning.

Afterwards, the polymerized wafer T on which all processes have been performed is transferred from the wafer transfer device 32 to the wafer transfer device 22 and transferred to the cassette C of the cassette placement table 10. In this way, the series of wafer processing in the substrate processing system 1 ends.

According to the above embodiment, the peripheral portion We of the wafer to be processed W is removed in two steps, step P1 and step P2. In step P1, since the particle size of the abrasive grains of the first grinding wheel 211 is large, the removal time of the first peripheral portion We1 can be shortened, and the throughput of wafer processing can be improved. Furthermore, in the subsequent step P2, since the particle size of the abrasive grains of the second grinding wheel 231 is small, the surface roughness of the finished surface of the removed second peripheral portion We2 can be reduced. By using the two grinding wheels 211 and 231 with different particle sizes in this way, the time required for removal of the peripheral portion We is shortened, and the surface of the wafer to be processed W exposed by grinding the second peripheral portion We2 is reduced. The surface properties and condition can be improved.

Additionally, according to this embodiment, in one substrate processing system 1, a series of processes can be performed continuously on a plurality of processing wafers W, thereby improving throughput.

<Dressing of grindstone wheel>

In step P2 of the above embodiment, when the second peripheral portion We2 of the wafer to be processed W is removed using the second grinding wheel 231, as shown in FIG. 8, the second peripheral portion ( The corner portion N of the bottom of We2) (the portion surrounded by a dotted line in the drawing) may be curved. In this case, after peeling the support wafer S from the target wafer W, a curved portion remains in the cross section of the target wafer W, so that the peripheral portion We of the target wafer W has a sharply pointed shape. Therefore, there is a risk that chipping may occur at the peripheral portion We of the wafer W to be processed and the wafer W to be processed may be damaged.

In this regard, 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 portion We2 shown in FIG. 8 The curvature of the corner portion N can be suppressed to some extent. However, when the second grindstone wheel 231 is repeatedly used, the grinding surface of the second grindstone wheel 231 is worn, and the corner portion N of the second peripheral portion We2 becomes prone to curve.

Therefore, it is desirable to perform so-called dressing to adjust the grinding surface of the second grindstone wheel 231. In dressing the second grindstone wheel 231, as shown in Figs. 1 and 9, the dress board 400 is used as an adjustment unit. The dress board 400 has a circular shape when viewed from the top, and has a step portion 401 on its periphery.

The dress board 400 is provided, for example, inside the second edge removal device 43 on the positive X-axis direction side of the second edge removal unit 230 . A moving mechanism 410 is provided on the lower surface of the dress board 400 to move and rotate the dress board 400 in the horizontal and vertical directions. The moving mechanism 410 has, for example, a shaft 411, two arms 412, 413, and a drive unit 414. The shaft 411 is provided between the lower surface of the dress board 400 and the distal 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 via the shaft 411 by this rotating part. The first arm 412 and the second arm 413 are connected by a joint (not shown), and this joint allows the first arm 412 to pivot around the proximal end. The second arm 413 is mounted on the drive unit 414, and the drive unit 414 allows the second arm 413 to pivot around the base end and move in the vertical direction. And, by the moving mechanism 410 provided with this structure, the dress board 400 can move forward and backward with respect to the second peripheral removal part 230 .

Additionally, the dress board 400 is not limited to the inside of the second peripheral removal device 43 described above and can be installed at any position. For example, the dress board 400 is placed on an installation location (not shown), such as a shelf, provided outside the second peripheral removal device 43, and is held in the chuck 200. Dressing may be performed.

In this case, while rotating the second grindstone 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 grindstone 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 grindstone wheel 231, the lower end that contacts the corner portion N of the second peripheral portion We2 shown in FIG. 8 is at a right angle. Then, when the second peripheral portion We2 is ground using the second grinding wheel 231 dressed in this way, the corner portion N of the second peripheral portion We2 can be formed at a right angle, thereby forming a curve. It can be suppressed.

In addition, in the dressing of the second grindstone wheel 231, the surfaces of the lower surface 231a and the outer surface 231b at the periphery of the second grindstone wheel 231 are measured in advance using, for example, a laser displacement meter. You can check the status. Specifically, for example, the height of the lower surface 231a and the outer surface 231b are measured. As a result of the inspection, if wear or abnormal protrusions are found on either or both the lower surface 231a and the outer surface 231b, the second grindstone wheel 231 may be dressed.

Additionally, from the viewpoint of suppressing the curvature of the corner portion N of the second peripheral portion We2, the second grindstone 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, making it difficult for the corner portion N of the second peripheral portion We2 to curve. .

In the above-mentioned example, dressing of the second grindstone wheel 231 was explained, but it is preferable to also dress the first grindstone wheel 211 using the same dress board 400.

<Other embodiments>

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 edge removal unit 230 is provided in the second edge removal device 43 outside the processing device 40, as shown in FIG. 10. It may be provided inside the processing device 40. In this case, the second peripheral removal unit 230 is disposed at the first machining position A1, and a rough grinding unit 140 and a finish grinding unit are provided at the second machining position A2 and the third machining position A3, respectively. 160 is placed. Also in this case, the intermediate grinding unit 150 is omitted.

The first periphery removal device 42 removes the first periphery We1 of the wafer W to be processed, but the range (the first width L1 and the first depth H1) is usually large. For this reason, even if the first grindstone wheel 211 with a large grain size is used, removal of the first peripheral portion We1 may take some time.

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

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

In the substrate processing system 1 of the above embodiment, the first edge removal section 210 and the second edge removal section 230 are provided separately, but they may be combined. For example, the first grindstone wheel 211 and the second grindstone wheel 231 are mounted in double concentric circles on a common support wheel (not shown). For example, if the diameter of the first grinding wheel 211 is increased and the diameter of the second grinding wheel 231 is reduced, the second grinding wheel 231 is disposed inside the first grinding wheel 211.

In this case, inside one periphery removal device, the periphery We of the wafer to be processed W is removed in two steps using two first periphery removal units 210 and second periphery removal units 230. It can be removed. Therefore, the throughput of wafer processing can be improved.

In the substrate processing system 1 of the above embodiment, the processing wafer W and the support wafer S are joined via an adhesive G, but instead of the adhesive G, for example, double-sided tape is used. You may use this to bond the processing wafer W and the support wafer S.

Although embodiments of the present invention have been described above, the present invention is not limited to these examples. It is obvious to those skilled in the art that various changes or modifications can be made within the scope of the technical idea described in the claims, and it is understood that they naturally fall within the technical scope of the present invention.

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Claims (17)

A substrate processing system for processing a substrate, comprising:
a first periphery removal unit having a first grindstone in contact with the periphery of the substrate, and removing the periphery by grinding it to a first depth;
A second periphery removal process comprising a second grindstone in contact with the periphery of the substrate, removing the periphery by the first periphery removal unit, and removing the periphery by further grinding the periphery to a second depth deeper than the first depth. With wealth,
The particle size of the abrasive grains included in the second grindstone is smaller than the particle size of the abrasive grains included in the first grindstone,
A substrate processing system comprising a grinding unit that grinds the processing surface of the substrate to a level between the first depth and the second depth after removing the peripheral part by the second periphery removal unit. A substrate processing system for processing a substrate, comprising:
a first periphery removal unit having a first grindstone in contact with the periphery of the substrate, and removing the periphery by grinding it to a first depth;
A second periphery removal process comprising a second grindstone in contact with the periphery of the substrate, removing the periphery by the first periphery removal unit, and removing the periphery by further grinding the periphery to a second depth deeper than the first depth. With wealth,
The particle size of the abrasive grains included in the second grindstone is smaller than the particle size of the abrasive grains included in the first grindstone,
A substrate processing system wherein a circumferential width of the peripheral portion removed by the second peripheral removal portion is smaller than a circumferential width of the peripheral portion removed by the first peripheral removal portion. According to claim 2,
a substrate holding portion that holds the substrate when the peripheral portion is removed from the first peripheral removing portion;
a lifting mechanism for raising and lowering the first grindstone;
A substrate processing system having a moving mechanism that moves the first grindstone and the substrate holding portion in a relatively horizontal direction. The method of claim 1 or 2,
a substrate holding portion that holds the substrate when the peripheral portion is removed from the second peripheral removing portion;
a lifting mechanism that raises and lowers the second grindstone;
A substrate processing system comprising a moving mechanism that moves the second grindstone and the substrate holding portion in a relatively horizontal direction. A substrate processing method for processing a substrate, comprising:
A first periphery removal step of contacting the periphery of the substrate with a first grindstone to grind and remove the periphery to a first depth;
After this, a second periphery removal process is performed in which a second grindstone is brought into contact with the peripheral portion of the substrate, and the peripheral portion is removed by grinding to a second depth deeper than the first depth,
The particle size of the abrasive grains included in the second grindstone is smaller than the particle size of the abrasive grains included in the first grindstone,
A substrate processing method comprising, after the second peripheral edge removal process, a grinding process of grinding the machined surface of the substrate to between the first depth and the second depth. A substrate processing method for processing a substrate, comprising:
A first periphery removal step of contacting the periphery of the substrate with a first grindstone to grind and remove the periphery to a first depth;
After this, a second periphery removal process is performed in which a second grindstone is brought into contact with the peripheral portion of the substrate, and the peripheral portion is removed by grinding to a second depth deeper than the first depth,
The particle size of the abrasive grains included in the second grindstone is smaller than the particle size of the abrasive grains included in the first grindstone,
A substrate processing method wherein the circumferential width of the peripheral portion removed in the second peripheral removal step is smaller than the circumferential width of the peripheral portion removed in the first peripheral removal step. The method of claim 5 or 6,
In the second periphery removal process,
With the second grindstone in contact with the peripheral portion of the substrate held in the substrate holding portion, the second grindstone is lowered to grind the peripheral portion to the second depth,
After this, the second grindstone is raised, and the second grindstone and the substrate holding part are moved relatively horizontally to separate them. delete delete delete delete delete delete delete delete delete delete

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