JP2020107779A - Substrate processing apparatus and substrate processing method - Google Patents

Abstract

To provide a technology of properly removing a material fixed on a surface of a rotating substrate with chemical solution.SOLUTION: A substrate processing apparatus 1 includes a processing unit 2. The processing unit 2 supplies chemical solution from an SPM nozzle 18 while rotating a substrate W horizontally around a rotation axis A1. A nozzle moving unit 20 moves the SPM nozzle 18 in a first direction D1. A top face of the substrate W is included in an imaging area of the camera 153. An image processing unit 3B detects a boundary B1 between a removed area R1 where resist has been removed and an unremoved area R2 where the resist is still fixed, in a captured image PI1 obtained by the camera 153. A nozzle move control apparatus 3D controls the nozzle moving unit 20 to move the SPM nozzle 18 in the first direction D1 in accordance with a position of the boundary B1.SELECTED DRAWING: Figure 7

Description

The present invention relates to a substrate processing apparatus and a substrate processing method for removing an object adhered to a substrate with a chemical solution. Examples of substrates to be processed include semiconductor substrates, FPD (Flat Panel Display) substrates such as liquid crystal display devices and organic EL (Electroluminescence) display devices, optical disk substrates, magnetic disk substrates, magneto-optical disk substrates, It includes a photomask substrate, a ceramic substrate, a solar cell substrate, a printed circuit board, and the like.

For example, in a photoresist process, which is one process of manufacturing a semiconductor device, a resist (photosensitive polymer) is applied on the surface of a semiconductor wafer (hereinafter referred to as a wafer) which is a substrate, and after exposure, development is performed to form a resist pattern. There is. The resist adhered to the surface of the wafer is peeled off from the wafer by treating the surface of the wafer with a predetermined chemical after development.

Further, in semiconductor device manufacturing, in order to form a p/n junction or the like in a device, an ion implantation step of irradiating the wafer with an ion beam of arsenic ions or the like is performed by using a resist applied to the wafer as a mask. There is. The resist used here is also eventually removed from the wafer, but it is known that the ion-implanted resist is difficult to remove. It is considered that this is because the surface of the resist is hardened by the ion implantation and the reactivity with the chemical solution is lowered.

In Patent Document 1, a cleaning liquid for stripping the resist is discharged from the cleaning nozzle to the center of the substrate while rotating the substrate, and is spread on the entire surface of the substrate by centrifugal force. Then, while the substrate is rotated, the cleaning liquid discharge position on the substrate is changed to an eccentric position deviated from the center of the substrate, and the gas discharge position side interface at the cleaning liquid discharge position and the gas discharge position by the gas nozzle are changed. Gas is discharged from the gas nozzle to the central portion of the substrate in a state where the distance from the interface on the cleaning liquid ejection position side is set to 9 mm to 15 mm to form a cleaning liquid drying region. Then, the supply position of the cleaning liquid is moved toward the peripheral edge of the substrate at a speed slower than the speed at which the drying region spreads outside.

JP 2012-142617 A

However, in Patent Document 1, the nozzle is simply moved at a speed according to the spread of the dry region. That is, the movement of the nozzle is controlled by the movement of the gas nozzle. For this reason, the resist may not be sufficiently removed from the substrate, which may cause a residue. Further, in the case of a resist that has been ion-implanted, the surface is hardened, and a residue is likely to be generated after the peeling process. Therefore, there is a demand for a technique for appropriately peeling off the resist adhered to the substrate.

An object of the present invention is to provide a technique for appropriately peeling an object adhered to the surface of a rotating substrate with a chemical solution.

In order to solve the above problems, a first aspect is a substrate processing apparatus for peeling an object adhered to a surface of a substrate with a chemical solution, and a substrate holder for holding the substrate in a horizontal posture and a substrate holder. A rotation motor that rotates around a vertical rotation axis that passes through the central portion of the substrate that is held, a nozzle that has a discharge port that discharges a chemical solution, and a movement that moves the nozzle in a first direction that is orthogonal to the rotation axis. A motor, a camera including the surface of the substrate in an imaging target area, and a captured image obtained by the camera, in the surface of the substrate, a peeling area where the object is peeled and the object is not fixed. A boundary detection unit that detects a boundary with the separation region, and a control unit that is connected to the movement motor and that moves the nozzle in the first direction according to the position of the boundary detected by the boundary detection unit. ..

A second aspect is the substrate processing apparatus of the first aspect, wherein the control unit controls the nozzle so that the chemical liquid from the nozzle is deposited on the side opposite to the first direction across the boundary. To move.

A third aspect is the substrate processing apparatus of the first aspect or the second aspect, wherein the control unit determines the moving speed of the nozzle based on the moving speed of the boundary in the first direction.

A fourth aspect is the substrate processing apparatus according to any one of the first to third aspects, wherein the ejection ports of the nozzles are oriented in a direction intersecting with a vertical direction.

A fifth aspect is the substrate processing apparatus according to any one of the first to fourth aspects, in which the first direction is a direction away from the rotation axis.

A sixth aspect is the substrate processing apparatus of the fifth aspect, wherein the control unit moves the liquid deposition position where the chemical liquid from the nozzle is deposited on the substrate from the position of the rotation axis in the first direction. Let

A seventh aspect is the substrate processing apparatus of the sixth aspect, wherein the boundary detection unit is configured to detect the boundary in a region on the second direction opposite to the first direction across the rotation axis line in the captured image. To detect.

An eighth aspect is the substrate processing apparatus according to any one of the first to seventh aspects, in which a processing chamber that accommodates the substrate holder and the nozzle therein and an atmosphere of the processing chamber are discharged to the outside. And an exhaust unit.

A ninth aspect is the substrate processing apparatus of the eighth aspect, wherein the exhaust unit generates a suction force on a radially outer side of the substrate.

A tenth aspect is the substrate processing apparatus according to any one of the first to ninth aspects, wherein the first pipe is connected to the nozzle and the first fluid flows, and the second fluid is connected to the nozzle. And a second pipe through which the fluid flows, and the nozzle mixes the first fluid and the second fluid and discharges the mixture from the discharge port.

An eleventh aspect is the substrate processing apparatus of the tenth aspect, including a flow rate changing unit that changes a flow rate of the first fluid from the first pipe and a flow rate of the second fluid from the second pipe. ..

A twelfth aspect is the substrate processing apparatus of the tenth aspect or the eleventh aspect, wherein the first fluid contains sulfuric acid and the second fluid contains hydrogen peroxide solution.

A thirteenth aspect is the substrate processing apparatus according to any one of the first to twelfth aspects, wherein the drainage pipe is provided below the substrate held by the substrate holder, and the substrate holding device. It further comprises a recovery pipe provided below the substrate held by the tool, and a switching unit for switching the pipe into which the chemical solution flows between the drainage pipe and the recovery pipe.

A fourteenth aspect is a substrate processing method for peeling an object adhered to the surface of a substrate with a chemical solution, comprising the steps of a) holding the substrate in a horizontal posture, and b) after the step a). Rotating around a vertical rotation axis, and c) after the step b), supplying a chemical solution to the surface of the substrate, the step c) includes c-1) of the substrate. A step of detecting a boundary between a peeled area where the object is peeled off and an unpeeled area where the object is fixed on the surface, c-2) of the boundary detected by the step c-1) Depending on the position, the step of moving the liquid deposition position where the chemical liquid is deposited on the surface of the substrate in a first direction orthogonal to the rotation axis.

According to the substrate processing apparatus of the first aspect, the boundary between the peeled area and the non-peeled area is detected, and the nozzle is moved according to the position of the boundary. Therefore, the liquid contact position of the chemical liquid can be moved according to the peeling condition of the target object, so that the target object fixed to the substrate can be effectively separated.

According to the substrate processing apparatus of the second aspect, the chemical liquid can be supplied to the unpeeled area.

According to the substrate processing apparatus of the third aspect, by determining the moving speed of the nozzle based on the moving speed of the boundary in the first direction, the nozzle can be moved at a speed suitable for peeling the object.

According to the substrate processing apparatus of the fourth aspect, by discharging the chemical liquid in a direction intersecting the vertical direction as compared with the case of discharging the chemical liquid vertically downward, the speed at which the chemical liquid reaches the substrate can be relaxed.

According to the substrate processing apparatus of the fifth aspect, by moving the nozzle in the direction away from the rotation axis, the liquid deposition position is moved from the inside of the substrate to the outside. Thereby, the object can be gradually peeled from the inside to the outside of the substrate.

According to the substrate processing apparatus of the sixth aspect, the object can be gradually separated from the substrate from the rotation center of the substrate to the outside.

According to the substrate processing apparatus of the seventh aspect, it is possible to prevent the detection of the boundary from being hindered by the fumes generated by the nozzles and peeling.

According to the substrate processing apparatus of the eighth aspect, fumes generated by peeling can be discharged to the outside. Thereby, the detection accuracy of the boundary area on the surface of the substrate can be improved.

According to the substrate processing apparatus of the ninth aspect, the gas generated above the substrate due to the peeling can be moved to the outside in the radial direction of the substrate. Thereby, the detection accuracy of the boundary area on the surface of the substrate can be improved.

According to the substrate processing apparatus of the tenth aspect, the chemical liquid generated by mixing the first fluid and the second fluid can be supplied to the nozzle. As a result, the active chemical solution can be supplied to the substrate.

According to the substrate processing apparatus of the eleventh aspect, it is possible to change the mixing ratio of the first fluid and the second fluid. This makes it possible to supply a chemical solution having different concentrations of the first fluid and the second fluid to the substrate.

According to the substrate processing apparatus of the twelfth aspect, SPM (sulfuric acid/hydrogen peroxide mixture) is generated by mixing sulfuric acid and hydrogen peroxide solution, and this can be supplied to the substrate. As a result, the resist adhered to the substrate can be removed.

According to the substrate processing apparatus of the thirteenth aspect, the inflow destination of the used chemical liquid can be switched between the drainage pipe and the recovery pipe. As a result, unnecessary chemicals can be discharged and necessary chemicals can be collected.

According to the substrate processing method of the fourteenth aspect, the boundary between the peeled area and the non-peeled area is detected, and the nozzle is moved according to the position of the boundary. Therefore, the liquid contact position of the chemical liquid can be moved according to the peeling condition of the target object, so that the target object fixed to the substrate can be effectively separated.

It is a schematic plan view for explaining the internal layout of the substrate processing apparatus 1 of the embodiment. It is a schematic sectional view for explaining an example of composition of processing unit 2 of an embodiment. It is sectional drawing which shows the front-end|tip part of the SPM nozzle 18 of embodiment typically. 3 is a block diagram for explaining an electrical configuration of a main part of the substrate processing apparatus 1. FIG. 6 is a flowchart for explaining an example of substrate processing by the processing unit 2. It is a perspective view which shows roughly the processing unit 2 in 1st SPM process S31. It is a figure which shows an example of the picked-up image PI1 acquired with the camera 153 in 1st SPM process S31. It is a schematic side view for explaining operation of each guard 43 and 44 in each process.

Embodiments of the present invention will be described below with reference to the accompanying drawings. The constituent elements described in this embodiment are merely examples, and the scope of the present invention is not limited thereto. In the drawings, for ease of understanding, the dimensions and number of each part may be exaggerated or simplified as necessary.

Expressions indicating relative or absolute positional relationship (for example, “along”, “parallel”, “orthogonal”, “center”, “coaxial”, etc.) not only represent the positional relationship strictly, unless otherwise specified. It also indicates a state of being displaced relative to an angle or a distance within a range where a tolerance or a similar function is obtained. Also, the expression “moving to” does not mean moving in parallel to a specific direction, but moving in a combined direction of the specific direction and the direction orthogonal to the specific direction, unless otherwise specified. Including that.

Unless otherwise specified, expressions that indicate equal states (for example, “identical”, “equal”, “homogeneous”, etc.) not only represent qualitatively exactly equal states, but also have tolerances or similar functions. The state in which there is a difference shall also be represented. Unless otherwise specified, expressions indicating a shape (for example, “square shape” or “cylindrical shape”) not only represent the shape in a geometrically strict manner, but also within a range in which a similar effect can be obtained, for example. A shape having irregularities, chamfers, etc. is also represented. The expressions “comprising”, “comprising”, “comprising”, “including” or “having” one element are not exclusive expressions that exclude the presence of other elements. Unless otherwise specified, the expression “upper” includes a case where two elements are in contact with each other and a case where two elements are apart from each other.

<1. Embodiment>
FIG. 1 is a schematic plan view for explaining the internal layout of the substrate processing apparatus 1 of the embodiment. The substrate processing apparatus 1 is a single-wafer processing apparatus that processes disk-shaped substrates W such as semiconductor wafers one by one.

The substrate processing apparatus 1 includes a plurality of load ports LP that hold a plurality of substrate containers C that contain a substrate W, and a plurality of substrates that are transported from the plurality of load ports LP with a treatment liquid such as a chemical liquid (for example, 12 processing units 2, a transfer robot that transfers the substrates W from the plurality of load ports LP to the plurality of processing units 2, and a controller 3 that controls the substrate processing apparatus 1. The transfer robot is an indexer robot IR that transfers the substrate W on the path between the load port LP and the processing unit 2, and a substrate transfer robot that transfers the substrate W on the path between the indexer robot IR and the processing unit 2. Including CR and.

The substrate processing apparatus 1 includes a plurality of fluid boxes 4 that accommodate valves and the like, and a storage box 6 that stores a sulfuric acid tank 27 (see FIG. 2) that stores sulfuric acid. The processing unit 2 and the fluid box 4 are arranged in a frame 5 of the substrate processing apparatus 1 and covered with the frame 5 of the substrate processing apparatus 1. Although the storage box 6 is arranged outside the frame 5 of the substrate processing apparatus 1 in the example of FIG. 1, it may be housed in the frame 5. The storage box 6 may be one box corresponding to the plurality of fluid boxes 4, or may be a plurality of boxes provided in one-to-one correspondence with the fluid boxes 4.

The twelve processing units 2 form four towers arranged so as to surround the substrate transfer robot CR in a plan view. Each tower includes three processing units 2 stacked one above the other. The four storage boxes 6 correspond to each of the four towers. Similarly, the four fluid boxes 4 correspond to four towers, respectively. The sulfuric acid stored in the sulfuric acid tank 27 in each storage box 6 is supplied to the three processing units 2 corresponding to the storage box 6 via the fluid box 4 corresponding to the storage box 6.

FIG. 2 is a schematic sectional view for explaining a configuration example of the processing unit 2 of the embodiment. The processing unit 2 holds a box-shaped chamber 7 having an internal space, a single substrate W in a horizontal posture inside the chamber 7, and places the substrate W around a vertical rotation axis A1 passing through the center of the substrate W. A spin chuck (substrate holding unit) 8 to be rotated, and an SPM (mixed solution of sulfuric acid (H ₂ SO ₄ ) and hydrogen peroxide solution (H ₂ O ₂ ) on the upper surface of the substrate W held by the spin chuck 8). SPM supply unit 9 for supplying sulfuric acid/hydrogen peroxide mixture: a foreign matter detection unit 150 for detecting a resist residue contained in SPM discharged from the substrate W, and a spin chuck 8 It includes a rinse liquid supply unit 10 for supplying a rinse liquid to the upper surface of the substrate W, and a cylindrical processing cup 11 surrounding the spin chuck 8. The chamber 7 is an example of an accommodation chamber that accommodates each sandwiching member 17 and the SPM nozzle 18.

In the following description, the direction orthogonal to the rotation axis A1 is referred to as “radial direction”. The direction toward the rotation axis A1 in the radial direction (direction approaching the rotation axis A1) is referred to as “inward in the radial direction”, and the direction toward the side opposite to the rotation axis A1 side in the radial direction (direction away from the rotation axis A1). ) Is called “radially outward”. The rotation direction around the rotation axis A1 may be referred to as “circumferential direction”.

The chamber 7 has a box-shaped partition 12, an FFU (fan filter unit) 14 as a blower unit for sending clean air from the upper part of the partition 12 into the partition 12 (corresponding to the inside of the chamber 7), and the lower part of the partition 12. An exhaust device (not shown) for exhausting the gas in the chamber 7 from the above.

As shown in FIG. 2, the FFU 14 is arranged above the partition wall 12 and attached to the ceiling of the partition wall 12. The FFU 14 sends clean air into the chamber 7 from the ceiling of the partition wall 12. An exhaust device (not shown) is connected to the bottom of the processing cup 11 via an exhaust duct 13 connected to the inside of the processing cup 11, and sucks the inside of the processing cup 11 from the bottom of the processing cup 11. A downflow (downflow) is formed in the chamber 7 by the FFU 14 and the exhaust device (not shown). The exhaust duct 13 constitutes an exhaust unit that exhausts the atmosphere inside the chamber 7 to the outside.

As the spin chuck 8, a sandwiching chuck that horizontally holds the substrate W and horizontally holds the substrate W is adopted. Specifically, the spin chuck 8 includes a spin motor (rotating unit) M, a spin shaft 15 integrated with a drive shaft of the spin motor M, and a disc mounted substantially horizontally on the upper end of the spin shaft 15. And a spin base 16 in the shape of a ring.

The spin base 16 includes a horizontal circular upper surface 16 a having an outer diameter larger than that of the substrate W. A plurality of (three or more, for example, six) holding members 17 are arranged on the peripheral edge of the upper surface 16a. The plurality of holding members 17 are arranged, for example, at equal intervals on the circumference of the upper surface of the spin base 16 on the circumference corresponding to the outer peripheral shape of the substrate W.

The SPM supply unit 9 includes an SPM nozzle 18, a nozzle arm 19 having the SPM nozzle 18 attached to its tip, and a nozzle moving unit 20 that moves the SPM nozzle 18 by moving the nozzle arm 19. The nozzle moving unit 20 has a moving motor that moves the nozzle in the horizontal direction orthogonal to the rotation axis A1. The SPM nozzle 18 is, for example, a straight nozzle that discharges SPM in a continuous flow state. The SPM nozzle 18 is attached to the nozzle arm 19 in a vertical posture in which the processing liquid is ejected in a direction perpendicular to the upper surface of the substrate W, for example. The nozzle arm 19 extends in the horizontal direction. The moving motor included in the nozzle moving unit 20 is connected to the control device 3 and can operate under the control of the control device 3.

The nozzle moving unit 20 moves the SPM nozzle 18 horizontally by horizontally moving the nozzle arm 19 around the swing axis. The nozzle moving unit 20 includes a processing position of the substrate W on which the SPM discharged from the SPM nozzle 18 lands on the upper surface of the substrate W and a retracted position where the SPM nozzle 18 is set around the spin chuck 8 in plan view. In between, the SPM nozzle 18 is moved horizontally. In this embodiment, the processing position includes, for example, the central position L1 at which the SPM ejected from the SPM nozzle 18 comes into contact with the central portion of the upper surface of the substrate W.

The SPM supply unit 9 further includes a sulfuric acid supply unit 21 that supplies sulfuric acid to the SPM nozzle 18, and a hydrogen peroxide solution supply unit 22 that supplies hydrogen peroxide solution to the SPM nozzle 18. The sulfuric acid supply unit 21 adjusts the sulfuric acid pipe 23 having one end connected to the SPM nozzle 18, the sulfuric acid valve 24 for opening and closing the sulfuric acid pipe 23, and the opening degree of the sulfuric acid pipe 23 so that the sulfuric acid pipe 23 flows. A sulfuric acid flow rate adjusting valve 25 for adjusting the flow rate of sulfuric acid and a sulfuric acid supply unit 26 to which the other end of the sulfuric acid pipe 23 is connected are included. The sulfuric acid valve 24 and the sulfuric acid flow rate adjusting valve 25 are housed in the fluid box 4. The sulfuric acid supply unit 26 is housed in the storage box 6. Each valve 25, 26 is connected to the control device 3 and can operate under the control of the control device 3.

The sulfuric acid flow rate adjustment valve 25 includes a valve body having a valve seat provided therein, a valve body that opens and closes the valve seat, and an actuator that moves the valve body between an open position and a closed position. The same applies to other flow rate adjusting valves.

The sulfuric acid supply unit 26 is stored in the sulfuric acid tank 27 that stores the sulfuric acid to be supplied to the sulfuric acid pipe 23, the sulfuric acid replenishment pipe 28 that replenishes the sulfuric acid tank 27 with a new solution of sulfuric acid, the recovery tank 29, and the recovery tank 29. And a liquid sending pipe 30 for sending the stored sulfuric acid to the sulfuric acid tank 27. Here, the “new liquid” means a liquid that is not used for processing the substrate W in the processing unit 2. The sulfuric acid supply unit 26 includes a first liquid sending device 31 that moves the sulfuric acid in the recovery tank 29 to the liquid sending pipe 30, a sulfuric acid supply pipe 32 that connects the sulfuric acid tank 27 and the sulfuric acid pipe 23, and a sulfuric acid supply pipe. It includes a temperature controller 33 that heats the sulfuric acid flowing through 32 to adjust the temperature, and a second liquid feeding device 34 that moves the sulfuric acid inside the sulfuric acid tank 27 to the sulfuric acid supply pipe 32.

The temperature adjuster 33 may be immersed in H ₂ SO ₄ in the sulfuric acid tank 27, or may be interposed in the middle of the sulfuric acid supply pipe 32 as shown in FIG. 2. The sulfuric acid supply unit 26 may further include a filter for filtering the sulfuric acid flowing through the sulfuric acid supply pipe 32, and/or a thermometer for measuring the temperature of the sulfuric acid flowing through the sulfuric acid supply pipe 32. Although the sulfuric acid supply unit 26 has two tanks in this embodiment, the structure of the recovery tank 29 is omitted and the sulfuric acid recovered from the processing cup 11 is directly supplied to the sulfuric acid tank 27. May be adopted. The first and second liquid delivery devices 31 and 34 are, for example, pumps. The pump sucks the sulfuric acid in the sulfuric acid tank 27 and discharges the sucked sulfuric acid.

The hydrogen peroxide solution supply unit 22 includes a hydrogen peroxide solution pipe 35 connected to the SPM nozzle 18, a hydrogen peroxide solution valve 36 for opening and closing the hydrogen peroxide solution pipe 35, and a hydrogen peroxide solution valve 36. And a hydrogen peroxide solution flow rate adjusting valve 37 for adjusting the opening degree to adjust the flow rate of the hydrogen peroxide solution flowing through the hydrogen peroxide solution valve 36. The hydrogen peroxide solution valve 36 and the hydrogen peroxide solution flow rate adjusting valve 37 are housed in the fluid box 4. Hydrogen peroxide solution at a room temperature (about 23° C.) whose temperature is not adjusted is supplied to the hydrogen peroxide solution pipe 35 from the hydrogen peroxide solution supply source housed in the storage box 6. Each valve 36, 37 is connected to the control device 3 and can operate under the control of the control device 3.

When the sulfuric acid valve 24 and the hydrogen peroxide solution valve 36 are opened, the sulfuric acid from the sulfuric acid piping 23 and the hydrogen peroxide solution from the hydrogen peroxide solution piping 35 are supplied into the casing (not shown) of the SPM nozzle 18. , Is thoroughly mixed (stirred) in the casing. By this mixing, the sulfuric acid and the hydrogen peroxide solution are uniformly mixed, and SPM, which is a mixed solution of the sulfuric acid and the hydrogen peroxide solution, is generated. SPM contains peroxymonosulfuric acid (H ₂ SO ₅ ) having a strong oxidizing power, and is heated to a temperature (100° C. or higher, for example, 160 to 220° C.) higher than the temperature of sulfuric acid and hydrogen peroxide solution before mixing. Be warmed. The generated high-temperature SPM is discharged from the discharge port 182 (see FIG. 3) opened at the tip (for example, the lower end) of the casing of the SPM nozzle 18. The casing of the SPM nozzle 18 is an example of a connection section mixing section.

FIG. 3 is a sectional view schematically showing the tip of the SPM nozzle 18 of the embodiment. The SPM nozzle 18 has a channel 181 extending vertically inside, and the tip of the channel 181 communicates with the discharge port 182. The discharge port 182 is provided to discharge the SPM, is provided on the side surface portion of the lower end of the SPM nozzle 18, and is oriented in the horizontal direction. The SPM supplied from the SPM supply unit 9 to the SPM nozzle 18 moves in the vertical direction by passing through the flow path 181, and then is discharged in the horizontal direction through the discharge port 182 at the lower end of the SPM nozzle 18. .. The SPM discharged from the discharge port 182 falls vertically downward due to gravity. When the SPM nozzle 18 is arranged above the substrate W, the SPM discharged from the SPM nozzle 18 reaches the surface of the substrate W.

In this way, in the SPM nozzle 18, the discharge direction of the SPM is made horizontal, so that the speed (landing speed) when the SPM lands on the substrate W below the SPM nozzle 18 can be made gentle. Accordingly, when a predetermined pattern (wiring pattern or the like) is formed on the upper surface of the substrate W, it is possible to prevent the pattern from collapsing due to the landing of the SPM. Further, since the discharge port 182 is oriented in the horizontal direction, it is possible to reduce dripping as compared with the case where the opening is oriented vertically downward. The term “dropping off” means here that when the liquid is controlled so as not to be discharged from the SPM nozzle 18 (for example, when the valves 24 and 36 are closed), the liquid becomes a droplet from the SPM nozzle 18. It means falling. The ejection port 182 does not have to be oriented straight in the horizontal direction, but may be oriented in a direction intersecting with the vertical direction. Therefore, for example, the SPM may be discharged obliquely downward by orienting the discharge port 182 in a combined direction of the vertical downward direction and the horizontal direction.

The openings of the sulfuric acid pipe 23 and the hydrogen peroxide solution pipe 35 are adjusted by the sulfuric acid flow rate adjusting valve 25 and the hydrogen peroxide solution flow rate adjusting valve 37, so that the sulfuric acid concentration of the SPM discharged from the SPM nozzle 18 is set to a predetermined value. It can be adjusted in the range. For example, the sulfuric acid concentration (mixing ratio) of the SPM discharged from the SPM nozzle 18 is H ₂ SO ₄ :H ₂ O ₂ =20:1 (sulfuric acid-rich high-concentration state) to 2:1 (excess ratio) as a flow rate ratio. It is adjusted within the range of (hydrogen oxide water-rich low-concentration state), and more preferably within the range of H ₂ SO ₄ :H ₂ O ₂ =20:1 to 3:1. The operations of the sulfuric acid flow rate adjusting valve 25 and the hydrogen peroxide solution flow rate adjusting valve 37 are controlled by the controller 3. The sulfuric acid flow rate adjusting valve 25, the hydrogen peroxide solution flow rate adjusting valve 37, and the control device 3 are an example of a flow rate changing unit.

The sulfuric acid supply unit 26 reuses the SPM recovered from the processing cup 11 as sulfuric acid. The SPM recovered from the processing cup 11 is supplied to the recovery tank 29 and stored in the recovery tank 29. Over time, the hydrogen peroxide solution contained in the SPM is decomposed, and the SPM stored in the recovery tank 29 changes to sulfuric acid. However, since the sulfuric acid changed from SPM contains a large amount of water, the concentration is adjusted appropriately. In the sulfuric acid supply unit 26, the sulfuric acid inside the recovery tank 29 is sent to the sulfuric acid tank 27, and the concentration thereof is adjusted in the sulfuric acid tank 27. As a result, SPM is reused as sulfuric acid.

The rinse liquid supply unit 10 includes a rinse liquid nozzle 47. The rinse liquid nozzle 47 is, for example, a straight nozzle that discharges the liquid in a continuous flow state, and is fixedly disposed above the spin chuck 8 with its discharge port facing the center of the upper surface of the substrate W. The rinse liquid nozzle 47 may be a movable nozzle that moves horizontally or vertically by the action of a motor that operates under the control of the control device 3. The controller 3 may scan the inside of the upper surface of the substrate W with the rinse liquid by moving the rinse liquid nozzle 47 in the horizontal direction.

To the rinse liquid nozzle 47, a rinse liquid pipe 48 to which the rinse liquid is supplied from the rinse liquid supply source is connected. A rinse liquid valve 49 for switching supply/stop of the rinse liquid from the rinse liquid nozzle 47 is provided in the middle of the rinse liquid pipe 48. When the rinse liquid valve 49 is opened, the rinse liquid supplied from the rinse liquid pipe 48 to the rinse liquid nozzle 47 is discharged from the discharge port set at the lower end of the rinse liquid nozzle 47. When the rinse liquid valve 49 is closed, the supply of the rinse liquid from the rinse liquid pipe 48 to the rinse liquid nozzle 47 is stopped. The rinse liquid is, for example, deionized water (DIW), but is not limited to DIW. The rinse liquid may be, for example, any of carbonated water, electrolytic ion water, hydrogen water, ozone water, ammonia water, and hydrochloric acid water having a diluted concentration (for example, about 10 ppm to 100 ppm). The rinse liquid may be used at room temperature, or may be heated with a heater to be hot water before use.

The processing cup 11 is arranged outside (in a direction away from the rotation axis A1) the substrate W held by the spin chuck 8. The processing cup 11 is formed of, for example, an insulating material. The processing cup 11 surrounds the side of the spin base 16. When the processing liquid is supplied to the substrate W while the spin chuck 8 is rotating the substrate W, the processing liquid supplied to the substrate W is shaken off around the substrate W. When the processing liquid is supplied to the substrate W, the upper end portion 11 a of the processing cup 11 opened upward is arranged above the spin base 16. Therefore, the processing liquid such as the chemical liquid or water discharged around the substrate W is received by the processing cup 11. Then, the processing liquid received by the processing cup 11 is sent to the recovery tank 29 or a waste liquid device (not shown).

The processing cup 11 includes a cylindrical member 40, a plurality of cups 41 and 42 fixedly arranged inside the cylindrical member 40 so as to surround the spin chuck 8 doubly, and a processing liquid scattered around the substrate W ( A plurality of guards 43 to 45 (first, second and third guards 43, 44, 45) for receiving the chemicals or rinses, and a guard elevating unit for independently elevating the respective guards 43 to 45 (distribution Destination switching unit) 46. The guard elevating unit 46 is composed of, for example, a ball screw mechanism, and includes an elevating motor that elevates and lowers the guards 43 to 45. The lifting motor is connected to the control device 3 and can operate under the control of the control device 3.

The processing cup 11 is foldable, and the guard elevating unit 46 elevates and lowers at least one of the three guards 43 to 45 to expand and fold the processing cup 11. The first cup 41 has an annular shape and surrounds the spin chuck 8 between the spin chuck 8 and the cylindrical member 40. The first cup 41 has a shape that is substantially rotationally symmetric with respect to the rotation axis A1 of the substrate W. The first cup 41 has a U-shaped cross section, and defines a first groove 50 for collecting and discharging the processing liquid used for processing the substrate W. A drainage port 51 is opened at the lowest point of the bottom of the first groove 50, and a first drainage pipe 52 is connected to the drainage port 51. The processing liquid introduced into the first drainage pipe 52 is sent to a drainage device (not shown) and processed by the device.

The second cup 42 has an annular shape and surrounds the periphery of the first cup 41. The second cup 42 has a shape that is substantially rotationally symmetric with respect to the rotation axis A1 of the substrate W. The second cup 42 has a U-shaped cross section, and defines a second groove 53 for collecting and collecting the processing liquid used for processing the substrate W. A drainage/recovery port 54 is opened at the lowest point of the bottom of the second groove 53, and a common pipe 55 is connected to the drainage/recovery port 54. A recovery pipe 56 and a second drainage pipe 57 are branched and connected to the common pipe 55. The other end of the recovery pipe 56 is connected to the recovery tank 29 of the sulfuric acid supply unit 26. A recovery valve 58 is installed in the recovery pipe 56, and a drain valve 59 is installed in the second drain pipe 57. By opening the recovery valve 58 while closing the drain valve 59, the liquid passing through the common pipe 55 is guided to the recovery pipe 56. Further, by opening the drainage valve 59 while closing the recovery valve 58, the liquid passing through the common pipe 55 is guided to the second drainage pipe 57. That is, the recovery valve 58 and the drain valve 59 function as a switching unit that switches the destination of the liquid passing through the common pipe 55 between the recovery pipe 56 and the second drain pipe 57. The second drainage pipe 57 is used exclusively for discarding the cleaning liquid when cleaning the inner wall 44a of the second guard 44, the second cup 42, and the common pipe 55.

The innermost first guard 43 surrounds the spin chuck 8 and has a shape substantially rotationally symmetrical with respect to the rotation axis A1 of the substrate W by the spin chuck 8. The first guard 43 has a cylindrical lower end portion 63 surrounding the spin chuck 8, a cylindrical portion 64 extending outward from the upper end of the lower end portion 63 (a direction away from the rotation axis A1 of the substrate W), and a cylinder. A cylindrical middle step portion 65 extending vertically upward from the outer peripheral portion of the upper surface of the groove portion 64, and an annular upper end extending obliquely upward from the upper end of the intermediate step portion 65 inward (direction approaching the rotation axis A1 of the substrate W). And a portion 66. The lower end portion 63 is located on the first groove 50, and is housed inside the first groove 50 in a state where the first guard 43 and the first cup 41 are closest to each other. The inner peripheral end of the upper end portion 66 has a circular shape having a larger diameter than the substrate W held by the spin chuck 8 in a plan view. Further, the upper end portion 66 may have a linear cross section as shown in FIG. 2, or may extend while drawing a smooth arc, for example.

The first guard 43 is made of, for example, a chemically resistant resin material (for example, fluorine such as PFA (tetrafluoroethylene/perfluoroalkyl vinyl ether copolymer), PCTFE (polychlorotrifluoroethylene), or PTFE (polytetrafluoroethylene). Resin). The entire area including the inner wall 43a of the first guard 43 is white. White includes ivory, cream, off-white, tan, light gray, custard cream, beige and the like.

The second guard 44, which is second from the inner side, is outside the first guard 43, surrounds the periphery of the spin chuck 8, and has a shape substantially rotationally symmetric with respect to the rotation axis A1 of the substrate W by the spin chuck 8. doing. The second guard 44 has a cylindrical portion 67 that is coaxial with the first guard 43, and an upper end portion 68 that extends obliquely upward from the upper end of the cylindrical portion 67 toward the center side (direction approaching the rotation axis A1 of the substrate W). ing. The inner peripheral edge of the upper end portion 68 has a circular shape having a larger diameter than the substrate W held by the spin chuck 8 in a plan view. The upper end portion 68 may have a linear cross-sectional shape as shown in FIG. 2, or may extend while drawing a smooth arc, for example. The tip of the upper end 68 defines the opening of the upper end 11 a of the processing cup 11.

The cylindrical portion 67 is located on the second groove 53. Further, the upper end portion 68 is provided so as to vertically overlap with the upper end portion 66 of the first guard 43, and with respect to the upper end portion 66 in a state where the first guard 43 and the second guard 44 are closest to each other. They are formed so as to be close to each other while keeping a minute gap. The second guard 44 is formed using, for example, a chemical resistant resin material (for example, a fluororesin such as PFA, PCTFE, or PTFE). The entire area including the inner wall 44a of the second guard 44 is white. White includes ivory, cream, off-white, tan, light gray, custard cream, beige and the like.

The outermost third guard 45 surrounds the spin chuck 8 on the outer side of the second guard 44 and has a shape substantially rotationally symmetric with respect to the rotation axis A1 of the substrate W by the spin chuck 8. .. The third guard 45 has a cylindrical portion 70 that is coaxial with the second guard 44, and an upper end portion 71 that extends obliquely upward from the upper end of the cylindrical portion 70 toward the center side (direction approaching the rotation axis A1 of the substrate W). ing. The inner peripheral edge of the upper end portion 71 has a circular shape having a larger diameter than the substrate W held by the spin chuck 8 in a plan view. The upper end portion 71 may have a linear cross-sectional shape as shown in FIG. 2, or may extend while drawing a smooth arc, for example.

The third guard 45 is formed using, for example, a chemically resistant resin material (for example, a fluororesin such as PFA, PCTFE, or PTFE). The entire area including the inner wall of the third guard 45 is white. White includes ivory, cream, off-white, tan, light gray, custard cream, beige and the like.

In this embodiment, the first groove 50 of the first cup 41, the inner wall 43 a of the first guard 43, and the outer periphery of the casing of the spin chuck 8 guide the chemical used in processing the substrate W. A distribution space (in other words, a drainage space) 101 is partitioned. In addition, the second circulation space through which the chemical used for processing the substrate W is guided by the second groove 53 of the second cup 42, the outer wall 43b of the first guard 43, and the inner wall 44a of the second guard 44. (In other words, the collection space) 102 is partitioned. The first distribution space 101 and the second distribution space 102 are isolated from each other.

The guard elevating/lowering unit 46 elevates and lowers the guards 43 to 45 between an upper position where the upper end of the guard is located above the substrate W and a lower position where the upper end of the guard is located below the substrate W. The guard lifting unit 46 can hold the guards 43 to 45 at any position between the upper position and the lower position. The supply of the processing liquid to the substrate W and the drying of the substrate W are performed in a state where any of the guards 43 to 45 faces the peripheral end surface of the substrate W (a state where the guards 43 to 45 are arranged at the trappable position).

In the first guard facing state of the processing cup 11 (see FIG. 8A) in which the innermost first guard 43 is opposed to the peripheral end surface of the substrate W (see FIG. 8A), all of the first to third guards 43 to 45 are included. Is placed in the upper position. In the second guard facing state of the processing cup 11 (see FIG. 8B) in which the second guard 44, which is second from the inner side, faces the peripheral end surface of the substrate W (see FIG. 8B), the second and third guards 44, 45 are provided. Is arranged in the upper position, and the first guard 43 is arranged in the lower position. In the third guard facing state of the processing cup 11 (see FIG. 8C) in which the outermost third guard 45 faces the peripheral end surface of the substrate W, the third guard 45 is arranged at the upper position, Moreover, the first and second guards 43 and 44 are arranged at the lower position. In the retracted state in which all the guards are retracted from the peripheral end surface of the substrate W (see FIG. 2 ), all of the first to third guards 43 to 45 are arranged at the lower position.

The foreign matter detection unit 150 includes an imaging unit 152 that images the SPM discharged from the substrate W. The foreign matter detection unit 150 detects the resist residue contained in the SPM discharged from the substrate W based on the color of the chemical liquid contained in the image captured by the image capturing unit 152. The foreign matter detection unit 150 includes, in addition to the imaging unit 152, an image processing unit 3B and an imaging control device 3C, which will be described next to the control device 3.

The image pickup unit 152 includes a camera 153 and a light source (not shown). The camera 153 generates an image signal based on the lens, an image sensor that converts the optical image formed by the lens into an electric signal, and the image signal based on the converted electric signal, and the image processing unit 3B (see FIG. 4)) and an image pickup circuit to be transmitted. The image pickup device includes a CCD image sensor, a CMOS image sensor, and the like. The camera 153 may be a high-speed camera capable of capturing images at a speed of several thousand to several tens of thousands per second, or a general camera capable of capturing images at a speed of about 10 to 100 per second. May be. The captured image is not limited to a still image and may be a moving image. The lens of the camera 153 is directed to the upper surface of the spin base 16. The imaging target area imaged by the camera 153 may include, for example, the entire upper surface of the substrate W held by each holding member 17 and the SPM nozzle 18 at the processing position. However, the camera 153 may be installed so as to capture only the determination area JA1 described below. The light source is disposed above the spin base 16 and illuminates the upper surface of the substrate W held by each holding member 17. The light source is, for example, a white light source.

FIG. 4 is a block diagram for explaining an electrical configuration of a main part of the substrate processing apparatus 1. The control device 3 is configured by using, for example, a microcomputer. The control device 3 has an arithmetic unit such as a CPU, a fixed memory device, a storage unit such as a hard disk drive, and an input/output unit. The storage unit includes a computer-readable recording medium in which a computer program executed by the arithmetic unit is recorded. A step group is incorporated in the recording medium so as to cause the control device 3 to execute a resist removing process described later.

The control device 3 follows a predetermined program and spin motor M (rotation motor), nozzle moving unit 20 (moving motor), guard elevating unit 46, first and second liquid transfer devices 31, 34, and temperature controller. 33 and other operations are controlled. Further, the control device 3 controls the opening/closing operations of the sulfuric acid valve 24, the hydrogen peroxide solution valve 36, the rinse liquid valve 49, etc. according to a predetermined program. Further, the control device 3 adjusts the openings of the sulfuric acid flow rate adjusting valve 25 and the hydrogen peroxide solution flow rate adjusting valve 37 according to a predetermined program.

The control device 3 includes an image processing unit 3B, an imaging control device 3C, and a nozzle movement control device 3D. These functional processing units are realized by software, for example, by the control device 3 executing a predetermined program process.

A camera 153 is connected to the control device 3. The imaging control device 3C controls the imaging operation of the camera 153. The image signal from the camera 153 is input to the image processing unit 3B. The image processing unit 3B performs image processing on the captured image indicated by this image signal. The image processing unit 3B has a peeled region R1 in which a target object (resist or a cured upper layer portion of the resist) fixed to the upper surface of the substrate W has been peeled off on the captured image, and the target object is not peeled off. A boundary B1 with the unpeeled area R2 is detected. The nozzle movement control device 3D controls the movement motor of the nozzle movement unit 20 according to the detected position of the boundary B1. Each of these processes will be described in detail later.

<Operation explanation>
FIG. 5 is a flow chart for explaining an example of substrate processing by the processing unit 2. The substrate processing example shown in FIG. 5 is a resist removing process for removing the resist from the upper surface (main surface) of the substrate W. Unless otherwise specified, the substrate processing shown in FIG. 5 is performed under the control of the control device 3. The resist, which is an object to be removed in this example, contains, for example, a resin (polymer), a photosensitizer, an additive, and a solvent as main components.

The resist removal process includes a carry-in process S1, a rotation start process S2, a first SPM process S31, a second SPM process S32, a rinse process S4, a drying process S5, a rotation stop process S6, and a carry-out process S7. Hereinafter, each step will be described.

In the carry-in step S1, the substrate W to be processed is carried into the chamber 7. Here, the substrate W to be processed is a substrate coated with a resist applicable to the ion implantation process, and also a substrate after the ion implantation process. The substrate W after the ion implantation step has, in order from the top, a hardened upper layer portion and a non-hardened lower layer portion. The hardened upper layer portion is relatively more difficult to remove by SPM than the non-hardened lower layer portion. Further, it is assumed that the resist (upper layer portion and lower layer portion) as the object is fixed to the entire upper surface of the substrate W. Further, it is assumed that the substrate W carried into the chamber 7 has not been subjected to the resist ashing process.

In the carry-in step S1, the controller 3 moves the hand of the substrate transport robot CR (see FIG. 1) holding the substrate W to the chamber 7 while the SPM nozzles 18 etc. are all retracted from above the spin chuck 8. The substrate W is transferred to the spin chuck 8 with its surface (device forming surface) facing upward and held by the spin chuck 8 (substrate holding step).

After the carrying-in step S1, the rotation start step S2 is performed. In the rotation start step S2, the control device 3 controls the spin motor M to start the rotation of the substrate W. The rotation speed of the substrate W is increased to a predetermined liquid processing speed (in the range of 150 to 1500 rpm, more preferably in the range of 150 to 300 rpm) and maintained at the liquid processing speed.

When the rotation speed of the substrate W reaches the liquid processing speed in the rotation start step S2, the first and second SPM steps S31 and S32 (chemical solution supply step) are performed. Here, the first SPM step S31 is performed first, and then the second SPM step S32 is performed.

FIG. 6 is a perspective view schematically showing the processing unit 2 in the first SPM step S31. 6A to 6D show the substrate W that rotates around the rotation axis A1 and the SPM nozzle 18 that moves above the substrate W. 6(a) and 6(b) show the SPM nozzle 18 at the center position L1, and FIG. 6(c) shows the SPM nozzle 18 between the center position L1 and the peripheral position L2. The intermediate position L12 is shown, and FIG. 6D shows the SPM nozzle 18 at the peripheral position L2.

In the first SPM step S31, the control device 3 controls the nozzle moving unit 20 to move the SPM nozzle 18 from the retracted position to the central position L1 which is the processing position. As shown in FIG. 6A, the center position L1 is a position where the SPM ejected from the SPM nozzle 18 comes in contact with the upper surface of the substrate W (hereinafter, this position is also referred to as “liquid contacting position LP1”). It is the nozzle position when it coincides with the rotation center of the substrate W. The rotation center of the substrate W is a horizontal position that coincides with the rotation axis A1 that is the rotation center of the sandwiching members 17. When the SPM nozzle 18 moves to the center position L1, the control device 3 simultaneously opens the valves 24 and 36 to supply sulfuric acid and hydrogen peroxide solution to the SPM nozzle 18. Sulfuric acid and hydrogen peroxide solution are mixed inside the SPM nozzle 18 to generate high-temperature (for example, 160 to 220° C.) SPM. The SPM is discharged from the discharge port 182 of the SPM nozzle 18 and reaches the center of the upper surface of the substrate W. Here, the concentration of SPM is kept constant over the entire period of the first SPM step S31. In the first SPM step S31, the control device 3 controls the valves 25 and 37 so that the hydrogen peroxide solution-rich SPM (for example, H ₂ SO ₄ :H ₂ O ₂ =3:1 to 5 at a flow rate ratio). 1:1 range) is supplied to the substrate W.

The SPM ejected from the SPM nozzle 18 reaches the upper surface of the substrate W and then flows outward along the upper surface of the substrate W by centrifugal force. Therefore, SPM is supplied to the entire upper surface of the substrate W, and a liquid film of SPM covering the entire upper surface of the substrate W is formed on the substrate W. As a result, the resist and SPM chemically react, and the resist on the substrate W is removed from the substrate W by SPM. The SPM that has moved to the peripheral portion of the substrate W scatters from the peripheral portion of the substrate W toward the sides of the substrate W.

When SPM is supplied to the central portion of the surface of the substrate W with the SPM nozzle 18 fixed at the central position L1, a peeling region R1 is formed in the central portion of the substrate W as shown in FIG. 6B. It Since the substrate W rotates about the rotation axis A1, the peeled region R1 is substantially circular in plan view. In the first SPM step S31, the control device 3 controls the nozzle moving unit 20 to move the SPM nozzle 18 from the central position L1 to the peripheral position L2 via the intermediate position L12. As shown in FIG. 6D, the peripheral position L2 is a nozzle position where the liquid deposition position LP1 coincides with the peripheral part of the substrate W. The peripheral portion of the substrate W is an annular region extending slightly from the outer peripheral edge of the substrate W to the inside (for example, 2 to 3 mm inside). The nozzle moving unit 20 moves the SPM nozzle 18 in the first direction D1 which is radially outward. As a result, the SPM landing position LP1 also moves in the first direction D1. Peroxomonosulfuric acid produced by mixing sulfuric acid and hydrogen peroxide water has decreased reactivity with the resist over time, and also has decreased reactivity due to a decrease in temperature. Therefore, by moving the liquid deposition position LP1 of SPM on the substrate W, SPM having high activity can be sequentially supplied to the entire region of the substrate W.

Further, in the first SPM step S31, when the control device 3 moves the SPM nozzle 18 from the central position L1 to the peripheral position L2, the control device 3 moves the SPM nozzle 18 according to the position of the boundary B1 between the peeled region R1 and the non-peeled region R2. Let Specifically, the image processing unit 3B of the control device 3 detects the boundary B1 by processing the captured image acquired by the camera 153. The image processing unit 3B is an example of a boundary detection unit. The nozzle movement control device 3D moves the SPM nozzle 18 in accordance with the radial position of the boundary B1 detected by the image processing unit 3B (hereinafter, referred to as “radial position”). Therefore, in the first SPM step S31, the moving speed during the movement of the SPM nozzle 18 from the central position L1 to the peripheral position L2 is not always constant, and the radial position of the boundary B1 (that is, the resist peeling state). Can vary depending on.

FIG. 7 is a diagram showing an example of a captured image PI1 acquired by the camera 153 in the first SPM step S31. As shown in FIG. 7, the nozzle movement control device 3D sets the determination area JA1 at a position overlapping the upper surface of the substrate W imaged in the captured image PI1. Here, the determination area JA1 is set on the upper surface of the substrate W on the second direction D2 side opposite to the first direction D1 across the rotation axis A1, and has a rectangular shape extending parallel to the first direction D1. It is set. The second direction D2 is parallel to the first direction D1 and is opposite to the first direction D1. The determination area JA1 is provided so as to include the rotation axis A1 here, but this is not essential.

When the SPM reacts with the resist in the unpeeled region R2, the peeled region R1 is formed inside the unpeeled region R2, as shown in FIG. The image processing unit 3B detects the boundary B1 between the peeled area R1 and the non-peeled area R2 in the determination area JA1. The boundary B1 may be detected by applying known image processing to the image portion of the determination area JA1 in the captured image PI1. As the image processing, for example, contrast adjustment for converting the difference between the brightness value corresponding to the peeled area R1 and the brightness value corresponding to the non-peeled area R2 to be large, binarization processing, or the peeling area R1 A process of extracting an edge with the peeled region R2 (edge detection using a Kenny filter or a Sobel filter) may be adopted.

As shown in FIG. 7, in the determination area JA1 of the captured image PI1, the boundary B1 appears as a group of pixels lined up in a curved line protruding outward in the radial direction. Therefore, in this curved linear pixel group, the radial position of the pixel located at the outermost radial direction and the radial position of the pixel located at the innermost radial direction may be set as the radial position of the boundary B1. Alternatively, the radial position of the boundary B1 may be derived from the plurality of pixels by averaging the radial positions of the plurality of pixels.

The nozzle movement control device 3D may appropriately derive the moving speed of the boundary B1 at each predetermined time interval and move the SPM nozzle 18 according to the moving speed. For example, the moving speed of the SPM nozzle 18 may be matched with the derived moving speed of the boundary B1. In this case, the SPM nozzle 18 can be moved so that the liquid landing position LP1 follows the boundary B1.

The boundary from the initial state where the peeling region R1 is not present on the upper surface of the substrate W as shown in FIG. 6A to the state where the peeling region R1 having a predetermined size is formed as shown in FIG. It may be difficult to accurately obtain the moving speed of B1. In this case, for example, the moving speed of the boundary B1 may be obtained after the radial position of the boundary B1 becomes the predetermined position. As a result, since the peeling region R1 becomes the predetermined size and the movement of the SPM nozzle 18 is started, the peeling region R1 can be satisfactorily widened while suppressing the generation of residues.

In addition, the nozzle movement control device 3D may derive the position where the SPM nozzle 18 is arranged from the detected radial position of the boundary B1. For example, the nozzle movement control device 3D derives a nozzle position at which the liquid landing position LP1 is separated from the boundary B1 in the second direction D2 by a predetermined distance d at predetermined time intervals, and the SPM nozzle is located at the nozzle position. 18 may be moved. Also in this case, the nozzle movement control device 3D can move the SPM nozzle 18 so that the liquid landing position LP1 follows the boundary B1.

Further, in this example, the ejection port 182 of the SPM nozzle 18 is directed in the second direction D2 which is the opposite direction to the first direction D1 which is the moving direction (scanning direction) of the SPM nozzle 18. Therefore, SPM is ejected from the SPM nozzle 18 in the second direction D2. Accordingly, since the SPM can be supplied radially inward, the residence time of the SPM on the upper surface of the substrate W can be extended as compared with the case where the SPM is supplied radially outward. Therefore, the resist can be peeled off well. In addition, it is not essential that the ejection port 182 is directed in the second direction D2 and may be directed in the first direction D1.

When the resist (including the cured upper layer portion) on the surface of the substrate W reacts with SPM, fumes may be generated. Fume is a gas or mist derived from the reaction of SPM and resist. In the present embodiment, the exhaust duct 13 generates a suction force radially outward around the substrate W (a region radially outward of the substrate W), so that the fumes generated above the substrate W are radially outward. Move towards. Therefore, the detection of the boundary B1 in the determination area JA1 is suppressed from being hindered by the fume.

In the processing unit 2, the area around the substrate W includes a first area SA1 and a second area SA2 (see FIG. 7). The second area SA2 is an area on the opposite side of the first area SA1 with the rotation axis A1 interposed therebetween. Since the first area SA1 is closer to the exhaust duct 13 than the second area SA2, the suction force in the first area SA1 is larger than that in the second area SA2. In this example, in the first SPM step S31, the SPM nozzle 18 moves so as to approach the first area SA1. The determination area JA1 is set on the surface of the substrate W closer to the second area SA2 than the first area SA1. The fumes generated on the upper surface of the substrate W are more likely to move to the first area SA1 having a stronger suction force than the second area SA2. Therefore, even if fumes are generated by the reaction between the resist and SPM, the fumes are reduced in the determination area JA1 close to the second area SA2. Therefore, it is possible to prevent the detection of the boundary B1 in the determination area JA1 from becoming difficult due to the fumes.

When the SPM nozzle 18 moves to the peripheral position L2, the control device 3 closes the valves 24 and 36 to stop the discharge of SPM from the SPM nozzle 18. As a result, the first SPM step S31 ends. Then, the 2nd SPM process S32 is performed.

In the second SPM step S32, the control device 3 moves the SPM nozzle 18 to the center position L1. When the SPM nozzle 18 is arranged at the central position L1, the control device 3 supplies the sulfuric acid and the hydrogen peroxide solution to the SPM nozzle 18 by simultaneously opening the sulfuric acid valve 24 and the hydrogen peroxide solution valve 36. Further, in the second SPM step S32, the control device 3 controls the valves 25 and 37 so that the SPM rich in sulfuric acid (for example, H ₂ SO ₄ :H ₂ O ₂ =20:1 in flow rate ratio) is applied to the substrate W. Supplied.

In the second SPM step S32, the control device 3 moves the SPM nozzle 18 from the central position L1 to the peripheral position L2. As a result, sulfuric acid-rich SPM is supplied from the central portion of the surface of the substrate W to the peripheral portion. After that, the control device 3 controls the nozzle moving unit 20 (see FIG. 2) to return the SPM nozzle 18 to the retracted position.

In this processing example, the substrate W is processed with SPM rich in hydrogen peroxide solution in the first SPM step S31. Therefore, in the first SPM step S31, the hardened upper layer portion of the resist on the substrate W is almost removed. Therefore, after the first SPM step S31, even if the resist remains on the substrate W, the resist can be peeled off relatively easily. Therefore, in the second SPM step S32, the remaining resist can be satisfactorily removed by processing with SPM rich in sulfuric acid.

After the second SPM step S32, the control device 3 performs the rinse step S4. In the rinse step S4, the rinse liquid is supplied to the substrate W. Specifically, the control device 3 opens the rinse liquid valve 49 and causes the rinse liquid nozzle 47 to discharge the rinse liquid toward the central portion of the upper surface of the substrate W. The rinse liquid discharged from the rinse liquid nozzle 47 reaches the center of the upper surface of the substrate W covered with the SPM. The rinse liquid that has landed on the central portion of the upper surface of the substrate W receives the centrifugal force due to the rotation of the substrate W and flows on the upper surface of the substrate W toward the peripheral portion of the substrate W. As a result, the SPM on the substrate W is pushed outward by the rinse liquid and discharged to the periphery of the substrate W. As a result, the SPM and the resist (that is, resist residues) remaining on the entire upper surface of the substrate W are washed away. The resist residue is, for example, a carbide. When a predetermined period has elapsed from the start of the rinse step S4, the control device 3 closes the rinse liquid valve 49 to stop the discharge of the rinse liquid from the rinse liquid nozzle 47.

After the rinse step S4, a drying step S5 for drying the substrate W is performed. In the drying step S5, the controller 3 controls the spin motor M so that the drying rotation speed is higher than the rotation speed of the substrate W in the first and second SPM steps S31 and S32 and the rinse step S4 (for example, several thousand rpm). The substrate W is accelerated until the substrate W is rotated at the drying rotation speed. Thereby, a large centrifugal force is applied to the liquid on the substrate W, and the liquid adhering to the substrate W is shaken off around the substrate W. In this way, the liquid is removed from the substrate W and the substrate W is dried.

When a predetermined time has elapsed after the high speed rotation of the substrate W was started in the drying step S5, the rotation stop step S6 is performed. In the rotation stop step S6, the controller 3 controls the spin motor M to stop the rotation of the substrate W by the spin chuck 8. After the rotation stop step S6, the carry-out step S7 is performed. In the carry-out step S7, the control device 3 causes the hand of the substrate transport robot CR to enter the inside of the chamber 7 and causes the hand of the substrate transport robot CR to hold the substrate W on the spin chuck 8. After that, the control device 3 retracts the hand of the substrate transfer robot CR from the chamber 7. As a result, the substrate W from which the resist has been removed from the upper surface (device formation surface) is carried out from the chamber 7.

FIG. 8 is a schematic side view for explaining the operation of each guard 43, 44 in each step. 8A is a schematic diagram for explaining the first SPM step S31, FIG. 8B is a schematic diagram for explaining the second SPM step S32, and FIG. It is a schematic diagram for explaining the drying step S5.

As described above, since the resist can be removed in the first SPM step S31, the SPM supplied to the substrate in the second SPM step S32 may hardly contribute to the resist removal. It may be desirable to collect such SPMs without discarding them from the viewpoints of environmental considerations and costs. Therefore, here, the SPM is collected in the second SPM step S32.

In the first SPM step S31, as shown in FIG. 8A, the control device 3 controls the processing cup 11 to bring it into the first guard facing state. In the second SPM step S32, as shown in FIG. 8B, the control device 3 controls the processing cup 11 to bring it into the second guard facing state.

In the first SPM step S31, a large amount of resist is peeled off on the surface of the substrate W, so that the SPM scattered (discharged) from the substrate W during this period contains a large amount of resist. Since this SPM containing a large amount of resist is not suitable for reuse, it is preferably discarded without being collected. Therefore, in the first SPM step S31, after the SPM nozzle 18 is arranged at the processing position, the control device 3 controls the guard elevating unit 46 to raise the first to third guards 43 to 45 to the upper position. .. As a result, as shown in FIG. 8A, the first guard 43 is opposed to the peripheral end surface of the substrate W. As a result, the first guard facing state is established.

In the first guard state, the SPM scattered from the peripheral portion of the substrate W land on the inner wall 43a of the first guard 43 (the inner wall 43a of the middle section 65). The SPM captured by the inner wall 43 a flows down along the inner wall 43 a of the first guard 43, is received by the first cup 41, and is sent to the first drainage pipe 52. The SPM sent to the first drainage pipe 52 is sent to a waste treatment facility outside the machine.

As described above, in the first SPM step S31, a large amount of resist is contained in the SPM scattered (discharged) from the substrate W. Therefore, the SPM containing the resist discharged from the substrate W is discharged through the first circulation space 101. That is, it is not collected and reused.

When the second SPM step S32 is started, the control device 3 controls the guard elevating unit 46 to lower the first guard 43 from the upper position to the lower position. As a result, as shown in FIG. 8B, the processing cup 11 is brought into the second guard facing state. In the second SPM step S32, the SPM scattered from the peripheral portion of the substrate W is captured by the inner wall 44a of the second guard 44. Then, the SPM flowing down the inner wall 44 a of the second guard 44 is sent to the recovery tank 29 of the sulfuric acid supply unit 26 through the second cup 42, the common pipe 55 and the recovery pipe 56. That is, the SPM scattered from the peripheral portion of the substrate W is collected through the second circulation space 102 and is reused.

When the rinse step S4 is started after the second SPM step S32, the control device 3 raises the first guard 43 to the upper position to bring the processing cup 11 into the first guard facing state (FIG. 8). (See (a)). Subsequently, when the drying step S5 is started, the control device 3 lowers the first and second guards 43 and 44 to the lower position. As a result, the processing cup 11 is brought into the third guard facing state, as shown in FIG. Further, when the carry-out step S7 is started, the control device 3 lowers the third guard 45 to the lower position. As a result, all of the first to third guards 43 to 45 are arranged at the lower position. Accordingly, the substrate transport robot CR can carry out the substrate W from the chamber 7 without interfering with the first to third guards 43 to 45.

As described above, in the second SPM process S32, the processing cup 11 changes from the first guard facing state to the second guard facing state, so that the distribution destination of the SPM discharged from the substrate W is the first discharge facing state. The liquid pipe 52 is switched to the recovery pipe 56. As a result, the distribution destination of the SPM discharged from the substrate W can be switched from drainage to recovery.

<2. Modification>
Although the embodiment has been described above, the present invention is not limited to the above-described one, and various modifications can be made.

In the above-described embodiment, in the first SPM step S31, the nozzle movement control device 3D moves the SPM nozzle 18 from the central position L1 to the peripheral position L2 radially outward (in the direction away from the rotation axis A1). Not required. For example, the nozzle movement control device 3D may move the SPM nozzle 18 from the peripheral edge position L2 to the central position L1 radially inward (direction approaching the rotation axis A1). Even in this case, the nozzle movement control device 3D moves the SPM nozzle 18 in accordance with the position of the boundary B1, so that the resist can be favorably peeled according to the peeling situation. Thereby, it is possible to reduce the generation of resist residue on the upper surface of the substrate W. Further, also in the second SPM step S32, the SPM nozzle 18 may be moved so as to approach the rotation axis A1.

In the above-described embodiment, in the substrate processing apparatus 1, the second SPM step S32 is performed after the first SPM step S31, but it is not essential to perform the second SPM step S32. For example, after the first SPM process S31, the second SPM process S32 may be skipped and the rinse process S4 may be performed.

In the above-described embodiment, the substrate in which the resist as the removal target is adhered to the entire upper surface of the substrate W has been described, but the substrate W is not necessarily limited to the resist W adhered to the entire upper surface. For example, in the processing unit 2, the resist to be removed may be fixed to only a part of the upper surface of the substrate W. Even in such a substrate W, by moving the SPM nozzle 18 in accordance with the position of the boundary B1, the target resist can be removed well. Further, in this case, the moving range of the SPM nozzle 18 may be limited so that the SPM is supplied to the region where the resist is fixed.

The substrate to be processed in the substrate processing apparatus 1 is not limited to the substrate W after the ion implantation process, and may be a substrate after a general exposure process, for example.

Further, it is not essential to remove the resist on the entire upper surface of the substrate W. For example, only a part of the entire upper surface of the substrate W may be set as the removal target area. In this case, the control device 3 may move the SPM nozzle 18 so that the SPM may land within the removal target area.

Although the present invention has been described in detail, the above description is illustrative in all aspects, and the present invention is not limited thereto. It is understood that innumerable variants not illustrated can be envisaged without departing from the scope of the invention. The configurations described in the above-described embodiments and modified examples can be appropriately combined or omitted as long as they do not contradict each other.

1 substrate processing apparatus 2 processing unit 3 control apparatus 7 chamber (processing chamber)
8 Spin chuck 9 SPM supply unit 11 Processing cup 13 Exhaust duct (exhaust part)
153 camera 16 spin base 17 holding member (substrate holder)
18 SPM Nozzle 182 Discharge Port 19 Nozzle Arm 20 Nozzle Moving Unit 21 Sulfuric Acid Supply Unit 22 Hydrogen Peroxide Water Supply Unit 23 Sulfuric Acid Pipe 24 Sulfuric Acid Valve 25 Sulfuric Acid Flow Rate Control Valve 26 Sulfuric Acid Supply Port 35 Hydrogen Peroxide Water Pipe 36 Hydrogen Peroxide Water Valve 37 Hydrogen peroxide water flow rate control valve 3B Image processing unit (boundary detection unit)
3C Imaging control device 3D Nozzle movement control device 41,42 Cup 43,44,45 Guard 46 Guard lifting unit 51 Drainage port 54 Recovery port 56 Recovery pipe A1 Rotation axis B1 Boundary D1 First direction D2 Second direction JA1 Judgment area L1 Center position L2 Edge position LP1 Liquid landing position M Spin motor (rotation motor)
PI1 photographed image R1 peeled area R2 unpeeled area SA1 first area SA2 second area W substrate

Claims (14)

A substrate processing apparatus for separating an object adhered to the surface of a substrate with a chemical solution,
A substrate holder for holding the substrate in a horizontal posture,
A rotation motor that rotates around a vertical rotation axis that passes through the central portion of the substrate held by the substrate holder,
A nozzle having a discharge port for discharging a chemical liquid,
A moving motor for moving the nozzle in a first direction orthogonal to the rotation axis;
A camera including the surface of the substrate in an imaging target area,
In a captured image obtained by the camera, on the surface of the substrate, a boundary detection unit that detects a boundary between a peeled area where the object is peeled and an unpeeled area where the object is fixed,
A control unit that is connected to the movement motor and moves the nozzle in the first direction according to the position of the boundary detected by the boundary detection unit;
A substrate processing apparatus comprising: The substrate processing apparatus according to claim 1, wherein
The said control part is a substrate processing apparatus which moves the said nozzle so that the said chemical|medical solution from the said nozzle may be liquid-landed on the opposite side to the said 1st direction on both sides of the said boundary. The substrate processing apparatus according to claim 1 or 2, wherein
The substrate processing apparatus, wherein the control unit determines a moving speed of the nozzle based on a moving speed of the boundary in the first direction. The substrate processing apparatus according to any one of claims 1 to 3,
The substrate processing apparatus, wherein the discharge port of the nozzle is oriented in a direction intersecting with a vertical direction. The substrate processing apparatus according to any one of claims 1 to 4, wherein:
The substrate processing apparatus, wherein the first direction is a direction away from the rotation axis. The substrate processing apparatus according to claim 5, wherein
The said control part is a substrate processing apparatus which moves the liquid deposition position which the said chemical|medical solution from the said nozzle lands on the said substrate to the said 1st direction from the position of the said rotation axis. The substrate processing apparatus according to claim 6, wherein
The substrate processing apparatus, wherein the boundary detection unit detects the boundary in a region on the second direction side opposite to the first direction across the rotation axis in the captured image. The substrate processing apparatus according to any one of claims 1 to 7, wherein
A processing chamber that houses the substrate holder and the nozzle therein;
An exhaust unit for discharging the atmosphere of the processing chamber to the outside,
A substrate processing apparatus further comprising: The substrate processing apparatus according to claim 8, wherein
The substrate processing apparatus, wherein the exhaust unit generates a suction force on a radially outer side of the substrate. The substrate processing apparatus according to any one of claims 1 to 9,
A first pipe connected to the nozzle, through which a first fluid flows,
A second pipe connected to the nozzle, through which a second fluid flows,
Further equipped with,
The substrate processing apparatus, wherein the nozzle mixes the first fluid and the second fluid and ejects the mixture from the ejection port. The substrate processing apparatus according to claim 10, wherein
A substrate processing apparatus comprising: a flow rate changing unit that changes a flow rate of the first fluid from the first pipe and a flow rate of the second fluid from the second pipe. The substrate processing apparatus according to claim 10 or 11, wherein
The first fluid comprises sulfuric acid,
The substrate processing apparatus wherein the second fluid contains hydrogen peroxide solution. The substrate processing apparatus according to any one of claims 1 to 12, wherein
A drainage pipe provided below the substrate held by the substrate holder,
A recovery pipe provided below the substrate held by the substrate holder,
A switching unit for switching the pipe into which the chemical liquid flows, between the drain pipe and the recovery pipe,
A substrate processing apparatus further comprising: A substrate processing method for peeling an object adhered to the surface of a substrate with a chemical solution,
a) a step of holding the substrate in a horizontal posture,
b) after the step a), rotating the substrate about a vertical rotation axis;
c) a step of supplying a chemical solution to the surface of the substrate after the step b),
Including
The step c) includes
c-1) a step of detecting a boundary between a peeled area where the object is peeled and an unpeeled area where the object is fixed on the surface of the substrate,
c-2) According to the position of the boundary detected in the step c-1), the liquid deposition position at which the chemical liquid deposits on the surface of the substrate is moved in a first direction orthogonal to the rotation axis. Process,
And a substrate processing method.

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