TW202401651A - Centering device, centering method and substrate processing apparatus - Google Patents

Abstract

This invention relates to a centering device, a centering method and a board processing device using the centering technique associated therewith wherein the center of a disciform board mounted on the upper surface of a board supporting part can be caused to coincide with the center of the board supporting part with high precision. This invention comprises: a gas supplying unit that supplies a gas between the board mounted on the upper surface of the board supporting part and the board supporting part; and a gas controlling unit that controls the gas supplying unit such that the gas intervenes between the board and the board supporting part during the positioning of the board. According to this invention, the frictional force between the lower surface of the board and the upper surface of the board supporting part is reduced because of the intervention of the gas between the board and the board supporting part. As a result, the influence of the frictional force is suppressed, thereby improving the centering precision.

Description

Centering device, centering method and substrate processing device

The present invention relates to a centering technology for aligning the center of a disk-shaped substrate placed on the upper surface of a substrate support part with the center of the substrate support part, and a substrate processing apparatus using this technology to process the substrate. This process includes bevel etching.

The disclosure content of the specification, drawings and patent scope of the Japanese application shown below are incorporated herein by reference in their entirety: Japanese Special Request 2022-104216 (application on June 29, 2022).

There is known a substrate processing apparatus that rotates a substrate such as a semiconductor wafer while supplying a processing liquid to the peripheral edge of the substrate to perform chemical processing, cleaning processing, or the like. For example, in the device described in Japanese Patent Application Laid-Open No. 2019-149423, the substrate is sucked and held while being supported from below by a rotating chuck (corresponding to an example of the "substrate support part" of the present invention). At this time, if the center of the rotating chuck and the center of the substrate are offset, the processing quality will be reduced. Therefore, in the above-described apparatus, before processing the substrate, a so-called centering process is performed to reduce the eccentricity of the substrate with respect to the spin chuck.

In the above-mentioned previous device, the substrate on the rotating chuck is pushed horizontally by the push rod in the state where the adsorption and holding is released. Thereby, the center of the substrate moves toward the center (rotation axis) of the rotary chuck. At this time, friction is generated between the substrate and the rotating chuck. The greater the eccentricity before centering, the greater the impact of this friction force. In addition, depending on the surface condition of the substrate, the greater the friction coefficient with the rotating chuck, the stronger the above influence.

The present invention was completed in view of the above-mentioned problems, and its object is to provide a centering technology and use that can accurately align the center of a disk-shaped substrate placed on the upper surface of the substrate support portion with the center of the substrate support portion. This centering technology substrate processing device.

The first aspect of the present invention is a centering device, which is characterized in that, with a disk-shaped substrate placed on the upper surface of the substrate support part in a horizontal position, the center of the substrate is aligned with the substrate support part. The substrate is horizontally moved and positioned in such a manner that the center of the substrate is aligned, and is provided with: a gas supply part that supplies gas between the substrate placed on the upper surface of the substrate support part and the substrate support part; and a gas control part that The gas supply part is controlled so that gas is interposed between the substrate and the substrate supporting part when the substrate is positioned.

Furthermore, a second aspect of the present invention is a centering method, characterized in that it includes the following step: with a disk-shaped substrate placed on the upper surface of the substrate support part in a horizontal position, the center of the substrate is aligned with the center of the substrate. The substrate is horizontally moved and positioned in such a manner that the centers of the substrate support parts are aligned; when the substrate is moved horizontally, gas is supplied between the substrate placed on the upper surface of the substrate support part and the substrate support part so that the gas is interposed between the substrates between support ministries.

Furthermore, a third aspect of the present invention is a substrate processing apparatus, which is characterized in that it processes the peripheral portion of a disc-shaped substrate with a processing liquid, and is provided with a substrate support portion for holding the substrate in a horizontal position. The upper surface of the support; the above-mentioned centering device; the suction part that exhausts air between the substrate positioned by the centering device and the substrate support part so that the substrate is adsorbed and held on the substrate support part; and the rotation drive part that adsorbs and holds the substrate The substrate support part rotates around the center of the substrate support part; the processing liquid supply mechanism supplies processing liquid to the peripheral part of the substrate that rotates around the center of the substrate support part integrally with the substrate support part.

In the invention thus configured, when the substrate is moved horizontally on the upper surface of the substrate support portion, gas is interposed between the substrate and the substrate support portion. Therefore, the friction force between the lower surface of the substrate and the upper surface of the substrate support portion is reduced. As a result, the influence of friction is suppressed.

As described above, according to the present invention, the center of the substrate and the center of the substrate supporting portion can be aligned with high accuracy.

Not all of the plurality of constituent elements of the above-mentioned aspects of the present invention are essential. In order to solve part or all of the above-mentioned problems, or to achieve part or all of the effects described in this specification, the above-mentioned plurality of constituent elements may be appropriately modified. A part of the constituent elements is changed, deleted, replaced with other new constituent elements, and part of the limited content is deleted. Furthermore, in order to solve part or all of the above-mentioned problems, or to achieve part or all of the effects described in this specification, part or all of the technical features included in the above-described aspect of the present invention may be combined with the above-described invention. Some or all of the technical features contained in other aspects of the invention are combined and used as an independent aspect of the invention.

FIG. 1 is a diagram showing a substrate processing system equipped with an embodiment of the substrate processing apparatus of the present invention. The substrate processing system 100 includes a substrate processing unit 110 that processes the substrate S, and a carrier unit 120 coupled to the substrate processing unit 110 . The carrier unit 120 is provided with a container holding unit 121 that can hold a plurality of containers C for accommodating the substrates S (a FOUP (Front Opening Unified Pod: Front Opening Pod) for accommodating a plurality of substrates S in a sealed state), SMIF (Standard Mechanical Interface: Standard Mechanical Interface) port, OC (Open Cassette: Open wafer cassette), etc.); the transfer robot 122 is used to receive the container C held in the container holding part 121, and transfer the unused wafer to the container C. The processed substrate S is taken out from the container C, or the processed substrate S is stored in the container C. A plurality of substrates S are accommodated in each container C in a substantially horizontal posture.

The transfer robot 122 is provided with: a base part 122a, which is fixed to the device frame; a multi-joint mechanical arm 122b, which is arranged to be rotatable around a vertical axis relative to the base part 122a; and a hand 122c, which is installed on the multi-joint machine. The front end of the arm 122b. The hand 122c has a structure capable of placing and holding the substrate S on its upper surface. Since this kind of transfer robot with a multi-joint robotic arm and a hand for holding a substrate is well known, its detailed description is omitted.

The substrate processing unit 110 includes a substrate transfer robot 111 arranged substantially in the center in plan view, and a plurality of processing units 1 arranged to surround the substrate transfer robot 111 . Specifically, a plurality of processing units 1 are arranged facing the space where the substrate transfer robot 111 is arranged. The substrate transfer robot 111 randomly accesses these processing units 1 and delivers the substrate S. On the other hand, each processing unit 1 performs predetermined processing on the substrate S. In this embodiment, one of the processing units 1 corresponds to the substrate processing apparatus 10 of the present invention.

FIG. 2 is a diagram schematically showing the structure of one embodiment of the substrate processing apparatus. FIG. 3 is a perspective view showing the structure of the substrate holding part and the centering mechanism of the substrate processing apparatus. Figure 4 is a diagram schematically showing the operation of the centering mechanism. "Adsorption" and "Purge" in the figure indicate the presence or absence of substrate adsorption and nitrogen purging, which will be described later.

The substrate processing apparatus 10 is an apparatus that performs a bevel etching process as an example of "processing" in the present invention, and supplies a processing liquid to the peripheral portion of the upper surface of the substrate S in a processing chamber. For this purpose, the substrate processing apparatus 10 includes a substrate holding portion 2 , a centering mechanism 3 , which is the main component of the centering device of the present invention, and a processing liquid supply mechanism 4 . Their actions are controlled by the control unit 9 of the entire control device.

The substrate holding part 2 is provided with a rotation base 21 which is a disc-shaped member smaller than the substrate S. The rotating base 21 is supported by a rotating spindle 22 extending downward from the center of the lower surface such that the upper surface 211 of the rotating base 21 is horizontal. The rotation support shaft 22 is rotatably supported by the rotation drive unit 23 . The rotation drive unit 23 has a built-in rotation motor 231 , and the rotation motor 231 rotates in accordance with the control command from the control unit 9 . Receiving this rotational driving force, the rotation base 21 rotates around a vertical axis AX (one-point chain line) extending in the vertical direction through the center 21C of the rotation base 21 . In Figure 2, the up and down directions are vertical directions. In addition, the plane perpendicular to the paper surface in Figure 2 is a horizontal plane. In addition, in order to clarify the directional relationship in the figures after Figure 2, the coordinate system with the Z-axis direction as the vertical direction and the XY plane as the horizontal plane is appropriately marked.

The upper surface 211 of the rotating base 21 has a size that can support the substrate S, and the substrate S can be placed on the upper surface 211 of the rotating base 21 . Although not shown in the figure, the upper surface 211 is provided with a plurality of adsorption holes or adsorption grooves. These adsorption holes are connected to the suction pump 24 via the suction pipe 241. When the suction pump 24 is operated according to the control command from the control unit 9 , the self-suction pump 24 exerts suction force on the rotating base 21 . As a result, air is discharged from between the upper surface 211 of the rotating base 21 and the lower surface of the substrate S, and the substrate S is adsorbed and held on the rotating base 21 . The substrate S thus adsorbed and held rotates around the vertical axis AX together with the rotation of the rotating base 21 . Therefore, when the center SC of the substrate S is inconsistent with the center 21C of the rotating base 21 , that is, the substrate S is eccentric, the quality of the bevel etching process will be reduced.

Therefore, in this embodiment, the centering mechanism 3 is provided. The centering mechanism 3 performs the centering process while the suction of the suction pump 24 is stopped (that is, while the substrate S can move horizontally on the upper surface 211 of the rotating base 21). By this centering process, the above-mentioned eccentricity is eliminated, and the center SC of the substrate S coincides with the center 21C of the rotation base 21 . In addition, the detailed structure and operation of the centering mechanism 3 will be described later.

In order to perform a bevel etching process on the substrate S after the centering process, a processing liquid supply mechanism 4 is provided. The processing liquid supply mechanism 4 has a processing liquid nozzle 41 , a nozzle moving part 42 that moves the processing liquid nozzle 41 , and a processing liquid supply part 43 that supplies the processing liquid to the processing liquid nozzle 41 . The nozzle moving part 42 moves the processing liquid nozzle 41 to a retracted position from above the substrate S to the side as shown by the solid line in FIG. 2, and a processing position above the peripheral edge of the substrate S as shown by the dotted line in the same figure. move between.

The processing liquid nozzle 41 is connected to the processing liquid supply part 43 . When an appropriate processing liquid is supplied from the processing liquid supply unit 43 to the processing liquid nozzle 41 positioned at the processing position, the processing liquid is ejected from the processing liquid nozzle 41 toward the peripheral edge of the rotating substrate S. Thereby, the bevel etching process of the processing liquid is performed on the entire peripheral part of the substrate S.

In addition, although illustration in FIG. 2 is omitted, the protective portion is provided to surround the substrate holding portion 2 from the side. During the bevel etching process, the protective portion captures the droplets of the processing liquid thrown out from the substrate S, effectively preventing the droplets from scattering to the periphery of the device.

Next, the structure of the centering mechanism 3 will be described with reference to FIGS. 2 to 4 . The centering mechanism 3 has the function of moving the substrate S horizontally on the upper surface 211 of the rotating base 21 in such a way that the center SC of the substrate S placed on the upper surface 211 of the rotating base 21 coincides with the center 21C of the rotating base 21 and positioning functions. As shown in FIG. 3 , the centering mechanism 3 has a contact member 31 arranged in the X2 direction (the right-hand direction of the figure) with respect to the center 21C of the rotating base 21 in the X direction, and a contact member 31 arranged in the X1 direction (the right-hand direction of the figure). The abutting members 32 and 33 on the left hand direction) side. Furthermore, the centering mechanism 3 has a moving mechanism 34 that moves the contact members 31 to 33 in the horizontal direction.

The moving mechanism 34 has a single moving part 35 for moving the contact member 31 and a multi-moving part 36 for moving the contact members 32 and 33 together. The single moving part 35 is arranged on the X2 direction side with respect to the center 21C of the rotating base 21 , while the multi-moving part 36 is arranged on the X1 direction side.

The single moving part 35 has a fixed base 351, a rotation motor 352, a power transmission part 353, and a slider 354. The rotating motor 352 is installed on the fixed base 351, and the power transmission part 353 and the slider 354 are sequentially stacked on the fixed base 351. The rotation motor 352 is a driving source for moving the contact member 31 in the X direction. When the rotation motor 352 is activated according to the control command from the control unit 9, the rotation shaft (not shown) rotates. The rotating shaft extends from the upper part of the fixed base 351 to the power transmission part 353 , and transmits the rotational driving force generated by the rotating motor 352 to the power transmission part 353 . The power transmission part 353 converts the rotational motion corresponding to the rotational driving force into the linear motion in the X direction through, for example, a rack and pinion structure, and transmits it to the slider 354 . Thereby, the sliding member 354 reciprocates in the X direction by a distance corresponding to the rotation amount. As a result, the contact member 31 mounted on the upper part of the slider 354 moves in the X direction as the slider 354 moves.

The multi-moving part 36 is basically configured in the same manner as the single-moving part 35 except for the structural part of the slider 364. That is, the multi-moving part 36 applies the rotational driving force generated by the rotation motor 362 mounted on the fixed base 361 to the slider 364 through the power transmission part 363, so that the slider 364 moves in the X direction. In the upper part of the sliding member 364, two arms 364a and 364b extending in the X2 direction are spaced apart from each other in the Y direction, and have a roughly C-shaped shape when viewed from vertically above. Furthermore, the contact members 32 and 33 are respectively attached to the end portions of the arms 364a and 364b on the X2 direction side. Therefore, when the rotation motor 362 operates according to the control command from the control unit 9 , the slider 364 reciprocates in the X direction by a distance corresponding to the rotation amount of the rotation motor 362 , similarly to the single moving part 35 . As a result, the contact members 32 and 32 attached to the slider 364 move in the X direction as the slider 364 moves.

In any one of the contact members 31 to 33, the mouth-shaped protrusion is provided with an end portion facing the substrate S. That is, the protruding portions (front end portions) of the contact members 31 to 33 have a sharp shape. Therefore, the contact members 31 to 33 can be in point contact with the side surface of the substrate S supported by the upper surface 211 of the rotating base 21 . When the contact member 31 moves in the X1 direction by the single moving part 35, the protruding portion 311 of the contact member 31 advances toward the center 21C of the rotating base 21 and contacts the side surface of the substrate S. Thus, in this embodiment, the moving direction D1 of the contact member 31 for contacting the substrate S is the X1 direction. And, after the contact, by further moving the contact member 31 in the D1 direction, the substrate S is pushed in the X1 direction and moved horizontally in the X1 direction on the upper surface 211 of the rotating base 21 . As described above, in this embodiment, in order to help understand the content of the invention, an imaginary line VL extending in the X1 direction from the center 21C of the rotating base 21 is additionally shown in FIGS. 3 and 4 . This is equivalent to the "imaginary line" of the present invention. Hereinafter, the description of the structure of the centering mechanism 3 will be continued while appropriately utilizing the imaginary line VL.

The movement pattern of the contact members 32 and 33 of the multi-movable part 36 is partially different from the movement pattern of the contact member 31 . This is because the contact members 32 and 33 are arranged linearly symmetrically with respect to the virtual line VL in the horizontal plane, and move in the X direction while maintaining this arranged state. More specifically, as shown in column (a) of FIG. 4 , the contact member 32 is disposed away from the imaginary line VL by a predetermined distance W (shorter than the radius rs of the substrate S) toward the Y2 direction side. On the other hand, the contact member 33 is disposed away from the imaginary line VL by the same distance W as the contact member 32 toward the opposite side of the contact member 32 , that is, the Y1 direction side. Therefore, when the contact members 32 and 33 move in the X2 direction by the multi-moving part 36, the protruding part 321 of the contact member 32 contacts the side surface of the substrate closer to the Y2 direction side than the imaginary line VL, and the contact member 33 The protruding portion 331 is in contact with the side surface of the substrate closer to the Y1 direction side than the imaginary line VL. In this way, in this embodiment, the moving direction D2 of the contact member 32 for contacting the substrate S is the X2 direction. In addition, the moving direction D3 of the contact member 33 for contacting the substrate S is also the X2 direction. Therefore, in order to move the protruding portions 311, 321, and 331 while maintaining the same distance from the center 21C of the rotating base 21 to the protruding portions 311, 321, and 331, the amount of movement per unit time must be equal to the contact member 31 is different from the contact members 32 and 33 . This point will be described in detail with reference to FIG. 4 , and centering processing using the above-mentioned movement pattern will be described.

In order to place the substrate S on the upper surface 211 of the rotation base 21 , it is desirable to position the protruding portions 311 , 321 , and 331 at the reference position taking into account at least the maximum value of the outer diameter tolerance of the substrate S. For example, in a substrate S with a diameter of 300 mm, the outer diameter tolerance is 0.2 mm. Therefore, the protruding portions 311, 321, and 331 must be separated from the center 21C of the rotating base 21 by a distance of 150.1 mm or more. In this embodiment, this distance is called "reference distance r0". As shown in column (a) of Figure 4, the radius of the center 21C of the rotating base 21 is the circle (one-point chain line) of the reference distance r0. is the base circle. Thus, in this embodiment, the reference distance r0 and the position on the reference circle are respectively equivalent to an example of the "first distance" and the "first position" of the present invention.

Next, a case where the contact members 31 to 33 are positioned so that the protruding portions 311, 321, and 331 are located on the reference circle and then the protruding portions 311, 321, and 331 are moved toward the substrate S will be discussed. In addition, for the purpose of the following explanation, the position of the contact member 31 for positioning the protruding portion 311 on the reference circle is referred to as the "first reference position", and the position of the contact member 32 for positioning the protruding portion 321 on the reference circle is referred to as the "first reference position". Let the position of the contact member 33 for positioning the protruding portion 331 on the reference circle be the "second reference position" and let it be the "third reference position".

Here, in a state where the contact members 31 to 33 are respectively located at the first reference position, the second reference position and the third reference position, the contact member 31 is moved toward the substrate S by the first movement amount Δd1 in the D1 direction (X1 direction). ) to discuss the situation of small movements. Correspondingly, if the contact members 32 and 33 are slightly moved by the same distance in the D2 direction (X2 direction), the distances from the center 21C of the rotating base 21 to the protruding portions 311, 321, and 331 will not match. Therefore, if the movement amount per unit time is unified and minute movements of the contact members 31 to 33 are repeated, the center SC of the substrate S will not coincide with the center 21C of the rotation base 21 .

On the other hand, as shown in column (b) of FIG. 4 , the distance Δd2 for slightly moving the contact member 32 and the distance Δd3 for slightly moving the contact member 33 can be set as follows: Among them, r1: the distance from the center 21C to the protruding portion 321 before slight movement, θ1: the angle between the straight line connecting the center 21C and the protruding portion 321 before the slight movement and the imaginary line VL, r2: the distance from the center after the slight movement. The distance between 21C and the protruding part 321, θ2: the angle formed by the straight line connecting the center 21C and the protruding part 321 after slight movement and the imaginary line VL, W: the separation distance between the contact member 32 and the imaginary line VL. In this case, even after slight movement, the distances from the center 21C of the rotating base 21 to the protruding portions 311, 321, and 331 are still the same. By repeating such minute movements, the contact members 31 to 33 are brought close to the substrate S while maintaining the same distance from the center 21C of the rotating base 21 to the protruding portions 311, 321, and 331. Therefore, for example, when an eccentric situation occurs as shown in FIG. 4 , in the process of repeating the above-mentioned minute movements, the contact member 31 first contacts the substrate S, causing the substrate S to move in the D1 direction (refer to FIG. 4 (column (c)). Then, the contact member 32 comes into contact with the substrate S pushed by the contact member 31 to move it horizontally. Moreover, as shown in column (d) of FIG. 4 , when the distance from the center 21C of the rotating base 21 to the protruding portions 311 , 321 , and 331 becomes the radius of the substrate S, the last contact member 33 also contacts the Substrate S. In this way, the substrate S is clamped by the contact members 31 to 33 to stop the movement of the substrate S, and the center SC of the substrate S coincides with the center 21C of the rotation base 21 . In this way, the centering process of the substrate S can be performed.

When the substrate S moves horizontally on the upper surface 211 of the rotating base 21 in this way, if the friction between the lower surface of the substrate S and the upper surface 211 of the rotating base 21 is relatively large, the above-mentioned problems will occur. problem. That is, due to the influence of friction, the accuracy of aligning the center SC of the substrate S with the center 21C of the rotating base 21, that is, the centering accuracy may be reduced. Therefore, in this embodiment, the purge part 37 is provided, and the nitrogen purge is started when, for example, the protruding parts 311, 321, and 331 are located at the close position shown by the one-dot chain line in column (b) of FIG. 4 . This close position means a position that is far away from the substrate S but closer to the substrate S than the reference circle, and is equivalent to an example of the "second position" in the present invention. Furthermore, the distance from the center 21C of the rotating base 21 to the close position corresponds to an example of the "second distance" in the present invention.

The purge part 37 is connected to the spin base 21 via the purge pipe 371, and can supply nitrogen as an example of "gas" in the present invention between the substrate S and the spin base 21. That is, on the upper surface 211 of the rotating base 21, in addition to the above-mentioned adsorption holes, adsorption grooves, etc., there are also ejection holes (not shown) for ejecting nitrogen gas. Furthermore, one end of the purge pipe 371 is connected to the discharge hole. The other end of the purge pipe 371 is connected to the purge part 37 . The purge part 37 has a nitrogen pipeline, a nitrogen supply source, a mass flow controller, a supply valve, etc. In this purge part 37, the supply valve opens and closes the flow path of the nitrogen line based on the command from the gas control part 94. For example, by opening the supply valve, nitrogen gas is supplied to the spin base 21 through the purge pipe 371, and is supplied from the discharge hole between the substrate S and the spin base 21. The flow rate of nitrogen so supplied can be adjusted by a mass flow controller. For example, as described below with reference to FIG. 7 , the supply flow rate of nitrogen gas per minute (hereinafter referred to as "N2 purge") can be adjusted in multiple stages between zero and 15 liters.

In order to measure the eccentricity of the substrate S after being centered by the above-mentioned centering mechanism 3, in this embodiment, an observation head 5 for observing the peripheral portion of the substrate S is provided. The observation head 5 is configured to be able to approach or separate from the peripheral edge of the substrate S. A head moving part 51 is connected to the observation head 5 . When the peripheral edge portion of the substrate S is observed with the observation head 5, the head moving unit 51 brings the observation head 5 close to the substrate S based on the observation command from the control unit 9 (observation processing). Furthermore, while the rotation base 21 that adsorbs and holds the substrate S rotates around the vertical axis AX, the peripheral edge portion of the substrate S is photographed using the observation head 5 . The captured image is sent to the control unit 9 . Based on the image obtained after the centering process, the eccentricity of the substrate S is calculated by the control unit 9 . Furthermore, the control unit 9 checks whether the bevel etching process has been performed satisfactorily based on the image obtained after the bevel etching process.

In this embodiment having the above-mentioned centering mechanism 3, the control unit 9 controls each device part of the substrate processing apparatus 10 to perform the above-mentioned centering process and the subsequent bevel etching process. This control unit 9 is provided with: a calculation processing unit 91, which is composed of a computer having a CPU (=Central Processing Unit: central processing unit) or RAM (=Random Access Memory: random access memory); and a hard disk drive. The memory unit 92 and the like; the motor control unit 93 that controls the rotation motors 352 and 362 of the moving mechanism 34; the gas control unit 94 that controls the purge unit 37; and the suction control unit 95 that controls the suction pump 24.

The arithmetic processing unit 91 appropriately reads the centering program or the bevel etching program stored in the memory unit 92 in advance, and expands it in the RAM (not shown). By controlling each part of the device as follows according to these programs, after performing the centering process shown in FIG. 5, the bevel etching process is performed.

FIG. 5 is a flowchart showing an example of centering processing performed by the device shown in FIGS. 2 and 3 . When the substrate processing apparatus 10 performs the centering process on the substrate S, the arithmetic processing unit 91 uses the motor control unit 93 to move the contact members 31 to 33 away from the rotation base 21 . More specifically, as shown in FIG. 4(a) , the contact members 31 to 33 are positioned so that the protruding portions 311, 321, and 331 are located on the reference circle. That is, the protruding portions 311, 321, and 331 correspond to an example of the "contact portion" in the present invention. Thereby, a transfer space sufficient for the hand (not shown) of the substrate transfer robot 111 to enter is formed above the rotating base 21 . After confirming that the formation of the transfer space is completed, the arithmetic processing unit 91 issues a loading request for the substrate S to the substrate transfer robot 111 . Then, the substrate transfer robot 111 places the substrate S on the rotation base 21 (step S1). In addition, at this point, the suction pump 24 stops, and the substrate S can move horizontally on the upper surface of the rotating base 21 .

After loading of the substrate S is completed, the substrate transfer robot 111 retreats from the substrate processing apparatus 10 . Next, the arithmetic processing unit 91 controls the moving mechanism 34 so that the three contact members 31 to 33 approach the substrate S. More specifically, the arithmetic processing unit 91 calculates the first movement amount Δd1 to the third movement amount Δd3, and controls the rotation motors 352 and 362 of the moving mechanism 34 via the motor control unit 93 based on the movement amounts Δd1 to Δd3. Thereby, the contact members 31 to 33 are slightly moved by the movement amounts Δd1 to Δd3 respectively. Each time such a slight movement occurs, the arithmetic processing unit 91 determines whether the protruding portions 311, 321, and 331 of the contact members 31 to 33 have reached the approach position (step S3). If the determination in step S3 is "NO", the arithmetic processing unit 91 returns to step S2 and repeats the minute movement. On the other hand, if the determination in step S3 is "YES", the arithmetic processing unit 91 starts the supply of nitrogen gas between the substrate S and the rotating base 21 when the supply, that is, the purge of nitrogen gas is not executed. , the purge part 37 is controlled to continue purging the nitrogen gas when the supply has started (step S4). By supplying the nitrogen gas, the nitrogen gas is interposed between the lower surface of the substrate S and the upper surface 211 of the rotating base 21 , and the friction force of the substrate S relative to the rotating base 21 is reduced.

In the next step S5, the arithmetic processing unit 91 calculates the load torque in the single moving part 35 from the motor current value applied to the rotating motor 352, and calculates the load torque in the multi-moving part 36 from the motor current value applied to the rotating motor 362. the load torque. Here, while the minute movement is repeated, the distance from the center 21C of the rotating base 21 to the protruding portions 311, 321, 331 (the distance from the center of the base to the protruding portions) changes, and along with this, the load torque For example, it changes as shown in Figure 6. As shown in the figure, when the above distance coincides with the radius rs of the substrate S, that is, when the contact members 31 to 33 sandwich the substrate S, the load torque in the single moving part 35 and the multi-moving part 36 increases sharply almost simultaneously. big. Therefore, the arithmetic processing unit 91 determines whether the load torque exceeds the threshold value TH (step S5).

If the determination in step S5 is negative, that is, the contact members 31 to 33 do not clamp the substrate S, the arithmetic processing unit 91 returns to step S2 and repeats the above series of steps (steps S2 to S4). On the other hand, if the determination in step S5 is YES, that is, the centering process has been completed, the arithmetic processing unit 91 stops the movement of the contact members 31 to 33. In addition, in this embodiment, although the fluctuation of the load torque of all the motors 352 and 362 is monitored, it is also possible to specify the movement stop timing of the contact members 31-33 by monitoring only one motor. Of course, the load torque can also be calculated based on something other than the motor current value.

When the centering process is completed, the arithmetic processing unit 91 stops the supply of nitrogen gas. Then, the arithmetic processing unit 91 controls the suction pump 24 to discharge air from between the upper surface 211 of the rotating base 21 and the lower surface of the substrate S. Thereby, the substrate S is adsorbed and held on the rotating base 21 . Furthermore, the arithmetic processing unit 91 retracts the contact members 31 to 33 from the substrate S so that the protruding portions 311, 321, and 331 are positioned on the reference circle (step S8).

At this stage, the process can also be moved to the bevel etching process, but in this embodiment, the eccentricity amount is checked. That is, the arithmetic processing unit 91 controls the observation head 5 to approach the substrate S and then image the peripheral portion of the substrate S. Furthermore, based on the image captured by the observation head 5, the arithmetic processing unit 91 calculates the offset amount of the center SC of the substrate S with respect to the vertical axis AX, that is, the eccentricity amount (step S9). When the eccentricity exceeds the allowable value (NO in step S10 ), the arithmetic processing unit 91 returns to step S2 and repeats the centering process after releasing the suction pump 24 from adsorbing the substrate S (step S11 ). In addition, in this embodiment, the centering process is repeated until the eccentricity converges below the allowable value. However, the centering process and the bevel etching process may be stopped when the number of repetitions reaches a predetermined value (for example, 2 times). , and notify the operator of the purpose.

On the other hand, when the eccentricity is less than the allowable value (YES in step S10), the arithmetic processing unit 91 ends the centering process and proceeds to the bevel etching process.

As described above, in this embodiment, nitrogen gas is supplied from the purge part 37 during the centering process, so that nitrogen gas is interposed between the lower surface of the substrate S and the upper surface 211 of the rotation base 21 . Therefore, the friction force in the centering process is greatly reduced. As a result, centering accuracy can be improved. In addition, damage to the lower surface of the substrate S can also be effectively suppressed. Among them, the improvement of centering accuracy is particularly evident from the inspection results shown in Figure 7.

Figure 7 is a graph showing the effect of N2 purge on centering accuracy. The data shown in this figure can be obtained through the following verification experiments. In the substrate processing device 10 having the centering mechanism 3 shown in Figures 2 and 3, while switching the N2 purge to zero, 1 liter, 3 liters, and 15 liters, the same wafer with a radius of 150 mm ( The substrate S) performs centering processing. Here, after the eccentricity amount of the wafer immediately after being placed on the rotating base 21 is found as the "eccentricity amount before centering", the eccentricity amount of the wafer after the centering process is performed with N2 purging = zero is as Find the "eccentricity after centering". Repeat this multiple times to obtain the results shown by the black circles in Figure 7. In addition, similarly, for N2 purge = 1 liter, 3 liters, and 15 liters, after calculating the "eccentricity amount before centering" and "eccentricity amount after centering", the black triangle marks in Figure 7, and The results are shown by the black square mark and the X mark. The following technical matters can be ascertained from Figure 7. That is, when nitrogen is not supplied (N2 purge=zero), the eccentricity after centering deviates greatly, and even exceeds 20 μm in some cases. On the other hand, by supplying nitrogen gas, the eccentricity amount after centering is reduced regardless of the size of the eccentricity before centering. Therefore, according to this embodiment accompanied by the supply of nitrogen gas, the centering accuracy can be greatly improved.

In addition, the supply of nitrogen is very effective in improving centering accuracy, but the difference in effect caused by the amount of supply seems to be small. Therefore, from the viewpoint of reducing the environmental burden, it is desirable to suppress the N2 purge to 3 liters or less. This is also effective in preventing the substrate S from falling off the rotation base 21 as described below.

If nitrogen gas is supplied to the lower surface of the substrate S in a state where the protruding portions 311, 321, and 331 of the contact members 31 to 33 are separated from the substrate S, the substrate S is interposed between the rotating base and the substrate S due to the supply of nitrogen gas. The existence of nitrogen gas between 21 causes horizontal shaking. In the worst case, the possibility that the substrate S may fall off the rotating base 21 cannot be denied. In this regard, by suppressing the N2 purge to a low level, the substrate S can be suppressed from falling off.

Furthermore, in this embodiment, after it is confirmed that the protruding portions 311, 321, and 331 of the contact members 31 to 33 have reached the approach position, the N2 purge is started. Therefore, even if the substrate S shakes, since the protruding portions 311, 321, and 331 are close to the substrate S, the substrate S can be effectively prevented from falling off. Therefore, centering processing can be performed stably.

In the above-described embodiment, the rotation base 21 and the center 21C respectively correspond to an example of the "substrate support part" and the "center of the substrate support part" in the present invention. In addition, the purge part 37 corresponds to an example of the "gas supply part" of this invention. In addition, the motor control unit 93 corresponds to an example of the "movement control unit" of the present invention. In addition, the suction pump 24 corresponds to an example of the "suction part" of the present invention.

In addition, the present invention is not limited to the above-described embodiments, and various changes can be made to the above-described embodiments as long as they do not deviate from the gist of the invention. For example, in the above-mentioned embodiment, the protruding portions 311, 321, and 331 have sharp shapes, but they may also have shapes such as a flat surface, a curved surface, a semicircle, and the like.

Furthermore, in the above-mentioned embodiment, the two contact members 32 and 33 are moved in the D2 direction (X2 direction) and the D3 direction (X2 direction) by the multi-moving part 36 respectively, but the same thing as the single moving part 35 may be provided. The contact member 32 is configured to have a single moving part and the contact member 33 is to have a single moving part instead of the multi-moving part 36. In addition, when the single movable portion for the contact member 32 and the single movable portion for the contact member 33 are provided in this way, it is not necessary to unify both the D2 direction and the D3 direction into the X2 direction, and the D2 direction and the D3 direction can be changed from the X2 direction. At least one of the D3 directions. The present invention can also be applied to devices having such centering mechanisms 3 .

Furthermore, in the above-described embodiment, the present invention is applied to the centering mechanism 3 that performs centering processing only by repeating the slight movement of the contact members 31 to 33 without measuring the amount of eccentricity before centering. However, its application target It is not limited to this. For example, it can also be applied to the device described in Japanese Patent Application Laid-Open No. 2019-149423. In this case, it is preferable to press the contact member (push rod) having a contact portion that can contact the end surface of the substrate against the end surface of the substrate based on the eccentricity before centering to move the substrate horizontally. Nitrogen gas is supplied between the substrate and the substrate support portion. Of course, the present invention can also be applied to a device that moves two or more contact members to perform centering processing.

Furthermore, in the above-mentioned embodiment, nitrogen is used as the "gas" in the present invention, but it goes without saying that other gases may also be used.

Furthermore, in the above embodiment, the present invention is applied to the centering device equipped in the substrate processing apparatus 10 that performs bevel etching. However, the centering device of the present invention can be applied to a disk-shaped substrate that is processed while rotating it. All centering devices or centering methods equipped in substrate processing equipment.

Although the invention has been described above based on specific embodiments, this description is not intended to be interpreted in a limiting sense. As with other embodiments of the present invention, various modifications to the disclosed embodiments will be apparent to those skilled in the art by referring to the description of the invention. Therefore, the scope of the appended patent application can be considered to include such modifications or embodiments within a scope that does not deviate from the true scope of the invention.

The present invention can be applied to the centering technology of aligning the center of a disk-shaped substrate placed on the upper surface of the substrate support part with the center of the substrate support part, and to the entire substrate processing apparatus that processes the substrate using this technology.

1: Processing unit 3: Centering mechanism 4: Treatment liquid supply mechanism 5: Observation head 9: Control unit (control part) 10:Substrate processing device 21: Rotation base (substrate support part) 21C: (center of rotating base) 22:Rotating pivot 23: Rotary drive part 24:Suction pump (suction part) 31: Contact member 32: Contact member 33: Contact components 34:Mobile mechanism 35:Single mobile unit 36:Multi-mobile department 37: Purge part (gas supply part) 41: Treatment fluid nozzle 42:Nozzle moving part 43: Treatment liquid supply department 51: Head moving part 91:Arithmetic processing department 92:Memory Department 93: Motor control department (movement control department) 94:Gas Control Department 95:Attraction Control Department 100:Substrate processing system 110: Substrate processing department 111:Substrate transfer robot 120: Transmission Department 121: Container holding part 122:Transport robot 122a: Base part 122b: Robotic arm 122c:Hand 211:(The upper surface of the rotating base) 231: Rotary motor 241:Suction piping 311:Busting Department 321:Protruding part 331:Protruding part 351: Fixed base 352: Rotary motor 353: Power transmission department 354:Sliding parts 361: Fixed base 362: Rotary motor 363:Power transmission department 364:Sliding parts 364a: arm 364b:arm 371:Purge piping AX: vertical axis C: Container D1: direction D2: direction D3: direction r0: reference distance r1: distance r2: distance rs:radius S:Substrate SC: Center (of the substrate) S1～S11: steps TH: threshold VL: imaginary line W: distance X: direction X1: direction X2: direction Y: direction Y1: direction Y2: direction Z: direction Δd1: Movement amount Δd2: Movement amount Δd3: Movement amount θ1: angle θ2: angle

FIG. 1 is a diagram showing a substrate processing system equipped with an embodiment of the substrate processing apparatus of the present invention. FIG. 2 is a diagram schematically showing the structure of one embodiment of the substrate processing apparatus. FIG. 3 is a perspective view showing the structure of the substrate holding part and the centering mechanism of the substrate processing apparatus. Figures 4(a)~(d) are diagrams schematically showing the operation of the centering mechanism. FIG. 5 is a flowchart showing an example of centering processing performed by the device shown in FIGS. 2 and 3 . FIG. 6 is a graph showing changes in load torque relative to changes in the distance from the center of the base to the protruding portion in the first embodiment. Figure 7 is a graph showing the effect of N2 purge on centering accuracy.

1: Processing unit

3: Centering mechanism

4: Treatment liquid supply mechanism

5: Observation head

9: Control unit (control part)

10:Substrate processing device

21: Rotation base (substrate support part)

21C: (center of rotating base)

22:Rotating pivot

23: Rotary drive part

24:Suction pump (suction part)

31: Contact member

32: Contact member

34:Mobile mechanism

35:Single mobile unit

36:Multi-mobile department

37: Purge part (gas supply part)

41: Treatment fluid nozzle

42:Nozzle moving part

43: Treatment liquid supply department

51: Head moving part

91:Arithmetic processing department

92:Memory department

93: Motor control department (movement control department)

94:Gas Control Department

95:Attraction Control Department

211:(The upper surface of the rotating base)

231: Rotary motor

241:Suction piping

351: Fixed base

352: Rotary motor

353: Power transmission department

354:Sliding parts

361: Fixed base

362: Rotary motor

363:Power transmission department

364:Sliding parts

371:Purge piping

AX: vertical axis

S:Substrate

SC: Center (of the substrate)

X: direction

Y: direction

Z: direction

Claims (5)

A centering device characterized in that, with a disk-shaped substrate placed in a horizontal position on the upper surface of the substrate support portion, the center of the substrate is aligned with the center of the substrate support portion. The above-mentioned substrate moves horizontally and is positioned, and has: a gas supply part that supplies gas between the substrate placed on the upper surface of the substrate support part and the substrate support part; and A gas control unit controls the gas supply unit so that the gas is interposed between the substrate and the substrate supporting unit when the substrate is positioned. For example, the centering device of claim 1 further has: A contact member having a contact portion capable of contacting the end surface of the substrate; A moving mechanism that moves the above-mentioned contact member; and A movement control unit that controls the movement mechanism in such a manner that the contact member moves away from the center of the substrate support portion in the horizontal direction by a distance longer than the radius of the substrate in an attitude that directs the contact portion toward the end surface of the substrate. The first position at the first distance moves toward the substrate via a second position that is horizontally away from the center of the substrate support portion by a second distance that is longer than the radius of the substrate and shorter than the first distance; and The gas control unit controls the gas supply unit to start supply of the gas when the contact member reaches the second position and to stop supply of the gas when positioning of the substrate is completed. For example, the centering device of claim 1 or 2, wherein The gas control unit controls the gas supply unit so that the supply amount of the gas per minute is 3 liters or less. A centering method characterized by the following steps: With the disk-shaped substrate placed in a horizontal position on the upper surface of the substrate support portion, the substrate is horizontally moved and positioned so that the center of the substrate coincides with the center of the substrate support portion; When the substrate moves horizontally, gas is supplied between the substrate placed on the upper surface of the substrate support part and the substrate support part, so that the gas is interposed between the substrate and the substrate support part. A substrate processing device, characterized in that it processes the peripheral edge of a disc-shaped substrate with a processing liquid, and is provided with: A substrate support portion having an upper surface for supporting the above-mentioned substrate in a horizontal posture; Such as requesting a centering device in item 1 or 2; a suction part that exhausts air between the substrate positioned by the centering device and the substrate support part to adsorb and hold the substrate on the substrate support part; a rotation drive unit that rotates the substrate support part that adsorbs and holds the substrate around the center of the substrate support part; and A processing liquid supply mechanism supplies the processing liquid to the peripheral edge portion of the substrate that rotates around the center of the substrate support portion integrally with the substrate support portion.