Substrate processing device and substrate processing method

Abstract

To provide a substrate processing device which suppresses particles generated on a surface of a substrate when drying the substrate using a process fluid in a supercritical state, and a substrate processing method.SOLUTION: A substrate processing device 1 which dries a substrate W in which a liquid film is formed on a pattern formation surface using a supercritical fluid comprises: a processing container 10 in which the substrate is stored and to which the supercritical fluid is supplied; a substrate holding section 20 including a base part 22 which supports the substrate from below in a state where the pattern formation surface is turned upward, and holding the substrate in the processing container; a first detection section 51 which detects an inclination of the base part to a horizontal plane; a posture adjustment mechanism 28 which adjusts the inclination of the base part to the horizontal plane; and a control section 100 which controls the posture adjustment mechanism based on a detection result of the first detection section, thereby leveling the base part.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a substrate processing apparatus and a substrate processing method.

Background Art

[0002] In recent years, in the manufacture of semiconductor devices, a supercritical drying process has been carried out in which a substrate with a wet upper surface is brought into contact with a supercritical processing fluid, and the processing fluid in the supercritical state is used to replace the processing liquid to dry the substrate. Patent Document 1 describes a supercritical drying method and an apparatus for carrying out the method. Patent Document 1 describes that first, a supercritical fluid is supplied at a small flow rate below the substrate in the chamber to prevent breakage of the substrate due to initial pressurization, and after the pressure in the chamber reaches a predetermined pressure, the supercritical fluid is supplied at a large flow rate toward the upper surface of the substrate.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present disclosure provides a technique capable of suppressing particles generated on the surface of a substrate when drying the substrate using a processing fluid in a supercritical state.

Means for Solving the Problems

[0005] According to one aspect of the present disclosure, there is provided a substrate processing apparatus for drying a substrate having a liquid film formed on a pattern formation surface using a supercritical fluid, the apparatus including: a processing vessel that houses the substrate and to which the supercritical fluid is supplied; a base portion that supports the substrate from below with the pattern formation surface facing upward; a substrate holding portion that holds the substrate in the processing vessel; and a first detection portion that detects an inclination of the base portion with respect to a horizontal plane.

Advantages of the Invention

[0006] According to the present disclosure, when drying a substrate using a processing fluid in a supercritical state, it is possible to suppress particles generated on the surface of the substrate.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

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Figure 8

Figure 9

Best Mode for Carrying Out the Invention

[0008] A supercritical drying apparatus 1 as an embodiment of a substrate processing apparatus will be described with reference to the accompanying drawings. For the sake of convenience of explanation, the directions will be indicated using the XYZ orthogonal coordinate system shown in each figure as necessary. The X direction and the Y direction are horizontal directions orthogonal to each other, and the Z direction is the vertical direction.

[0009] As shown in FIG. 1, the supercritical drying apparatus 1 has a processing container 10 formed as a supercritical chamber. A processing space 12 is formed inside the processing container 10. The processing container 10 has an opening 14 on its side surface, which serves as an entrance to the processing space 12.

[0010] The processing container 10 has a fluid supply unit 16 and a fluid discharge unit 18. A processing fluid is supplied from a supply source of a supercritical processing fluid (for example, carbon dioxide in a supercritical state), not shown, to the fluid supply unit 16 (see the arrow), and is discharged from the fluid supply unit 16 into the processing space 12. The fluid supply unit 16 is composed of, for example, a nozzle. The processing fluid is discharged to the outside of the processing space 12 through the fluid discharge unit 18 (see the arrow). Although detailed description of the supply system and the discharge system of the processing fluid is omitted, any known configuration in a supercritical drying apparatus can be adopted.

[0011] The supercritical drying apparatus has a substrate holding unit 20. In the illustrated embodiment, the substrate holding unit 20 is formed as a tray movable in the horizontal direction (X direction), and has a substantially plate-shaped base portion 22 and a lid 24 connected to one end of the base portion 22.

[0012] On the upper surface of the base portion (base portion main body) 22, at least three (four in the illustrated example) support pins 26 are provided so as to protrude upward. The support pins 26 can be moved up and down in the vertical direction by, for example, a linear actuator 260 (see FIG. 2) built in the base portion (base portion main body) 22. The support pins 26 can be mainly used to finely adjust the height position and the posture (tilt with respect to the horizontal plane) of a substrate W such as a semiconductor wafer supported by the support pins 26. Here, the portion (plate-like portion) of the base portion 22 excluding the support pins 26 is also referred to as the base portion main body.

[0013] An attitude adjustment mechanism 28 for adjusting the tilt of the base portion 22 with respect to the horizontal plane is provided between the base portion 22 and the lid body 24. As shown in FIG. 2, the attitude adjustment mechanism 28 can be composed of, for example, a base body 281 having a U-shaped (angle arc-shaped) cross section and a total of eight movable push pins 282 attached to the base body 281. Each movable push pin 282 can be moved in the vertical direction by a linear actuator 283. The linear actuator 283 may include, for example, a ball screw. The eight movable push pins 282 are divided into two groups. As schematically shown in FIG. 4, four movable push pins 282 of the first group are provided on one side of the lid body 24, and four movable push pins 282 of the second group are provided on the other side of the lid body 24. According to this configuration, it is obvious that the tilt of the base portion 22 with respect to the horizontal plane (specifically, both the tilt direction and the tilt amount) can be freely adjusted by adjusting the height position (Z-direction position) of the tip of each movable push pin 282. The configuration of the attitude adjustment mechanism 28 is not limited to that shown in FIG. 2, and any configuration can be adopted as long as the tilt of the base portion 22 with respect to the horizontal plane can be freely adjusted.

[0014] The substrate holding unit 20 is movable horizontally between a "processing position (the position shown in FIGS. 6 and 8 described later)" and a "retracted position (the position shown in FIG. 1)". When the substrate holding unit 20 is in the processing position, the lid 24 is inserted into the opening 14 of the processing container 10 to seal the opening 14, and the base portion 22 is accommodated in the processing space 12. When the substrate holding unit 20 is in the retracted position, the lid 24 opens the opening 14, and the base portion 22 exits to the outside of the processing space 12.

[0015] The processing container 10 is fixed to the pedestal 30. The pedestal 30 can be configured to have a generally rectangular shape in plan view with the X direction as the long side direction and the Y direction as the short side direction, for example. The pedestal 30 is attached to the machine frame 40 (frame) of the substrate processing apparatus via three or more (for example, four) elevating actuators 32. The machine frame 40 can be regarded as a stationary structure to which various components of the supercritical drying apparatus are fixed. The elevating actuators 32 can be provided at the four corners of the rectangular pedestal 30. The elevating actuator 32 can be, for example, a linear actuator having an electric rotary motor and a ball screw or the like.

[0016] A guide rail 34 extending in the horizontal direction (X direction) is provided on the pedestal 30. On the guide rail 34, a traveling body 36 that moves along the guide rail 34 by a driving force generated by a driving mechanism (for example, built in the traveling body 36) (not shown) is provided. The substrate holding unit 20 is attached to the traveling body 36 via an arm 38. Therefore, by moving the traveling body 36 along the guide rail 34, the substrate holding unit 20 can be moved between the above-described processing position and the retracted position.

[0017] Below the substrate holding part 20 at the retracted position, a substrate lifter 60 that can move up and down in the vertical direction by a substrate lifter moving mechanism (not shown) is provided. The substrate lifter 60 has three or more (three in the illustrated example) lift pins 62. By raising the substrate lifter 60 to the raised position, the substrate W supported by the substrate holding part 20 (specifically, the support pins 26) can be supported and lifted by the tips of the lift pins 62. To enable this, the base part 22 is provided with through holes through which the lift pins 62 can pass. The positions of the through holes are indicated by reference numeral 62P in FIGS. 3 and 4.

[0018] When the substrate lifter 60 is in the raised position, the substrate W can be transferred between a substrate transfer arm (not shown) that has entered the supercritical drying apparatus 1 from the back side to the front side in the Y direction in FIG. 1 and the substrate lifter 60. That is, when loading the substrate W before processing, the substrate W before processing can be loaded by executing the following steps (S1) to (S3). (S1) With the substrate holding part 20 positioned at the retracted position, the empty substrate lifter 60 is positioned at the raised position. (S2) A substrate transfer arm (not shown) places the substrate W on the lift pins 62 of the substrate lifter 60. (S3) After the substrate transfer arm is retracted from above the base part 22, the substrate lifter 60 is lowered, thereby transferring the substrate W from the substrate lifter 60 to the support pins 26 of the base part 22. When unloading the substrate W after processing, the reverse procedure of the above may be executed.

[0019] The substrate lifter 60 may be configured to be movable only in the vertical direction. Also in this case, it is possible to avoid interference between the substrate lifter 60 and its peripheral components. Instead of this, the substrate lifter 60 may be configured to be movable not only in the vertical direction but also in the Y direction (the depth direction of the paper surface in FIG. 1). By doing so, it becomes easier to avoid interference between the substrate lifter 60 and its peripheral components.

[0020] The supercritical drying apparatus 1 has a plurality of distance measuring sensors. The distance measuring sensors can be, for example, optical distance measuring sensors using infrared rays or lasers. The distance measuring sensors are fixed to the machine frame 40 itself or to a sensor holder (not shown) fixed to the machine frame 40. The plurality of distance measuring sensors include a plurality (four in the illustrated example) of first distance measuring sensors 51, a plurality (five in the illustrated example) of second distance measuring sensors 52, a plurality (five in the illustrated example) of third distance measuring sensors 53, and a plurality (four in the illustrated example) of fourth distance measuring sensors 54.

[0021] The first distance measuring sensor 51 is located below the base portion 22 of the substrate holding portion 20 in the retracted position (the position shown in FIG. 1), and measures the vertical distance (the distance measured along the Z direction) from each of the first distance measuring sensors 51 to the lower surface of the base portion 22 of the substrate holding portion 20.

[0022] The second distance measuring sensor 52 is located below the base portion 22 of the substrate holding portion 20 in the retracted position, and measures the vertical distance from each of the second distance measuring sensors 52 to the lower surface of the substrate W supported on the base portion 22 of the substrate holding portion 20 (specifically, on the support pin 26). In order for the sensor light of the second distance measuring sensor 52 to reach the lower surface of the substrate W, the base portion 22 of the substrate holding portion 20 is provided with through holes equal in number to the second distance measuring sensors 52. The through holes are located on the optical axis (the optical path of the sensor light) of the second distance measuring sensor 52 when the substrate holding portion 20 is in the retracted position. The through holes can be provided, for example, at the positions indicated by reference numeral 52p in FIGS. 3 and 4.

[0023] As long as the sensor light of the second distance measuring sensor 52 can reach the lower surface of the substrate W, it is not necessary to provide through holes equal in number to the second distance measuring sensors 52. That is, it is sufficient if some kind of notch is provided in the base portion 22.

[0024] The third distance measuring sensor 53 is located above the base portion 22 of the substrate holding portion 20 in the retracted position, and measures the vertical distance from each of the third distance measuring sensors 53 to the upper surface of the substrate W supported on the base portion 22 of the substrate holding portion 20 (specifically, the surface of the liquid film formed on the upper surface of the substrate W).

[0025] The fourth distance measuring sensor 54 is located above the four corners of the pedestal 30, and measures the vertical distance from each of the fourth distance measuring sensors 54 to the four corners of the pedestal 30. Based on the measurement values of the fourth distance measuring sensor 54, the inclination of the pedestal 30 with respect to the horizontal plane (the inclination of the upper surface of the pedestal 30) can be detected.

[0026] In FIG. 3, an example of the irradiation position 51p of the sensor light of the first distance measuring sensor 51 on the lower surface of the base portion 22 is indicated by a black circle. The large circle We indicated by a broken line shows the position of the periphery (edge) of the substrate W. The irradiation position 51p of the sensor light of the first distance measuring sensor 51 is near the periphery of the substrate W in plan view. The irradiation positions 51p are respectively arranged at angular positions on the circumference of a circle centered on the center of the substrate W and dividing the circumference into N equal parts (N is the number of the first distance measuring sensors, and is 4 in the illustrated example).

[0027] Based on the detection values of the first distance measuring sensor 51, the inclination direction and the inclination amount (inclination angle) of the base portion 22 with respect to the horizontal plane (a plane perpendicular to the direction of gravity) can be specified. If N is 3 or more, it is obvious that the inclination direction and the inclination amount of the base portion 22 can be specified. Here, N = 4 is used to increase the measurement reliability by redundancy.

[0028] Note that calibration (any of mechanical calibration, electrical calibration, and calibration in arithmetic processing) of the first distance measuring sensor 51 is performed when the supercritical drying apparatus 1 is installed. For example, if the measurement target surface (here, the lower surface of the base portion 22) is horizontal, the detection values of the first distance measuring sensor 51 are all the same. This also applies to the second to fourth distance measuring sensors.

[0029] In FIG. 3, an example of the irradiation position 52p of the sensor light of the second distance measuring sensor 52 on the lower surface of the substrate W is indicated by a white circle. There is one irradiation position 52p of the sensor light of the second distance measuring sensor 52 at the center of the substrate W and four at the vicinity of the periphery. The four irradiation positions 52p in the vicinity of the periphery of the substrate W are arranged on the circumference of a circle centered on the center of the substrate W and at angular positions that divide the circumference into four equal parts.

[0030] Based on the detection value of the second distance measuring sensor 52, the tilt direction and tilt amount (tilt angle) of the substrate W with respect to the horizontal plane can be specified. Since there is an IPA liquid film on the surface of the substrate W, it is difficult to accurately measure the tilt of the substrate W itself from the surface side of the substrate W. However, by irradiating the back surface of the substrate W with detection light, it becomes possible to accurately measure the tilt of the substrate W.

[0031] Also, since the irradiation position 52p of the second distance measuring sensor is also set at the center of the substrate W, if the substrate W is bent, the bending can also be detected. The number of the second distance measuring sensors 52 is not limited to five and can be changed according to the required redundancy.

[0032] As shown in FIG. 3, it is preferable to attach the two arms 38 to both sides of the lid 24 of the substrate holding portion 20. By doing so, it becomes easy to design the device (component layout) that ensures that the arms 38 do not interfere (collide) with the first distance measuring sensor 51 and the second distance measuring sensor 52 within their moving ranges.

[0033] In FIG. 4, an example of the irradiation position 53p of the sensor light of the third distance measuring sensor 53 on the upper surface of the substrate W (specifically, the surface of the liquid paddle on the upper surface) is indicated by a hatched circle. The irradiation position 53p of the sensor light of the third distance measuring sensor 53 is set to one at the center of the substrate W and four at the vicinity of the periphery, similar to the second distance measuring sensor 52. In the illustrated example, the irradiation position 53p of the sensor light of the third distance measuring sensor 53 is at a position where the irradiation position 52p of the sensor light of the second distance measuring sensor 52 is shifted by 45 degrees around the center of the substrate W, but it is not limited to this.

[0034] Based on the detection value of the third distance measurement sensor 53, it is possible to detect the height and uniformity of the liquid level of the liquid film (paddle) on the upper surface of the substrate W. If the height of the liquid level is too high, there is a risk that the liquid will come into contact with the lower surface of the ceiling wall that defines the processing space 12 of the processing container 10. If the height of the liquid level is too low, there is a risk of drying failure due to early drying. If the liquid level height is non-uniform, there is a risk of local contact of the liquid with the lower surface of the ceiling wall. Also, when the liquid level height is non-uniform, the thickness of the liquid film may be non-uniform, and in this case, there is a risk of local drying failure, a large generation of particles, or pattern collapse.

[0035] In addition, for example, the four support pins 26 provided on the upper surface of the base portion 22 can be provided directly below the irradiation positions 53p (the four near the periphery) of the sensor light of, for example, the third distance measurement sensor 53. Alternatively, the four support pins 26 may be arranged at angular positions that divide the circumference of a circle centered on the center of the substrate W into four equal parts.

[0036] As shown in FIG. 1, the supercritical drying apparatus 1 has a control unit 100. The control unit 100 is, for example, a computer and includes an arithmetic unit 101 and a storage unit 102. The storage unit 102 stores programs for controlling various processes executed in the supercritical drying apparatus 1 (or a substrate processing system including the supercritical drying apparatus 1). The arithmetic unit 101 controls the operation of the supercritical drying apparatus by reading and executing the programs stored in the storage unit 102. The programs may have been recorded on a computer-readable storage medium and installed from that storage medium into the storage unit 102 of the control unit 100. Examples of computer-readable storage media include hard disks (HD), flexible disks (FD), compact disks (CD), magneto-optical disks (MO), memory cards, and the like.

[0037] Next, the operation of the supercritical drying apparatus 1, particularly the operation from the time when the substrate W is passed from a substrate transfer arm (not shown) to the support pin 26 of the substrate holding unit 20 in the retracted position via the substrate lifter 60 until the substrate holding unit 20 moves from the retracted position to the processing position for the processing of the substrate W will be described. Note that, for example, an IPA paddle (liquid film) is formed on the surface (pattern formation surface) of the substrate W, and the concave portions of the pattern on the surface are filled with IPA. The substrate W has been subjected to, for example, (1) chemical liquid treatments such as wet etching and chemical liquid cleaning, (2) a rinsing treatment for washing away the chemical liquid with a rinsing liquid, and (3) an IPA substitution treatment for substituting the rinsing liquid with IPA to form an IPA paddle (liquid film) in a single-wafer cleaning apparatus (not shown). In many cases, a plurality of supercritical drying apparatuses 1 and a plurality of the above-described single-wafer cleaning apparatuses are combined to form a single substrate processing (liquid processing and drying) system, and in this substrate processing system, the substrate is transported by the above-described substrate transfer arm.

[0038] The operations described below are automatically performed under the control of the control unit 100 based on a processing recipe stored in the storage unit 102 of the control unit 100 or transmitted from a host computer of the control unit 100.

[0039] <Adjustment Step 1: Horizontal Extension of the Pedestal 30> First, detection light is irradiated from each of the first to third distance measuring sensors 51 to 53 onto a substrate W placed with its surface (pattern formation surface) facing upward on the support pins 26 of the substrate holding portion 20 at the retracted position, and detection light from the fourth distance measuring sensor 54 is irradiated onto the four corners of the upper surface of the pedestal 30. Then, based on the detection result of the fourth distance measuring sensor 54, the inclination of the pedestal 30 with respect to the horizontal plane is detected. If the inclination exceeds the allowable range, the leveling of the pedestal 30 is performed by appropriately operating one or more of the four lifting actuators 32. Note that the leveling (inclination adjustment) of the pedestal 30 is not limited to this timing immediately before substrate processing, and may be performed after substrate processing, during standby (for example, when waiting for the loading of the next substrate W after the substrate W has been unloaded from the supercritical drying apparatus 1). The leveling of the pedestal 30 can be performed at any timing during the operation of the supercritical drying apparatus 1, for example, during supercritical drying processing.

[0040] <Adjustment Step 2: Leveling of the Base Portion 22> Next, detection light is again irradiated from each of the first to fourth distance measuring sensors 51 to 54. Then, based on the detection result of the first distance measuring sensor 51, the inclination of the base portion 22 with respect to the horizontal plane is detected. If the inclination exceeds the allowable range, the leveling of the base portion 22 is performed by operating the posture adjustment mechanism 28 provided in the substrate holding portion 20.

[0041] <Adjustment Step 3: Leveling of the Substrate W> Next, detection light is irradiated from each of the first to fourth distance measuring sensors 51 to 54. Then, based on the detection result of the second distance measuring sensor 52, the inclination of the substrate W on the base portion 22 with respect to the horizontal plane is detected. If the inclination exceeds the allowable range, the leveling of the substrate W is performed by operating the support pins 26 provided in the base portion 22.

[0042] <Adjustment Step 4: Height Adjustment of the Substrate W> Next, detection light is irradiated from each of the first to fourth distance measuring sensors 51 to 54. Then, based on the detection result of the third distance measuring sensor 53, the height of the surface of the IPA paddle on the surface of the substrate W on the base portion 22 is detected. When the height exceeds the allowable range, the support pin 26 provided on the base portion 22 is operated to lower the height of the substrate W to an appropriate height.

[0043] <Adjustment Step 5: Final Confirmation> Next, detection light is irradiated from each of the first to fourth distance measuring sensors 51 to 54. If there are no problems with any of the inclination of the pedestal 30 with respect to the horizontal plane, the inclination of the base portion 22 with respect to the horizontal plane, the inclination of the substrate W with respect to the horizontal plane, and the height of the surface of the IPA paddle on the surface of the substrate W obtained from the detection values of the first to fourth distance measuring sensors 51 to 54, the substrate holding portion 20 can be moved to the processing position to start the supercritical drying process.

[0044] The supercritical drying process can be carried out by a known method described in, for example, a prior application of the applicant of the present application (such as Japanese Patent Application Laid-Open No. 2020-170873 and many others). For example, by supplying a processing fluid (such as carbon dioxide) in a supercritical state from a supply source (not shown) into the processing space 12, the pressure in the processing space 12 is increased to a predetermined pressure (pressure increasing step), and then, by circulating the supercritical fluid in the processing space 12, the IPA on the substrate W is replaced with the processing fluid (circulation step). When the replacement is completed, the processing fluid is discharged from the processing space 12 and the processing space 12 is depressurized to normal pressure. As a result, the processing fluid in the supercritical state vaporizes, and the substrate W can be dried while preventing pattern collapse. At this time, if the surface of the substrate W is inclined, the in-plane uniformity of the IPA film thickness deteriorates, which in turn causes deterioration of the in-plane uniformity of the supercritical fluid replacement, and this may cause pattern collapse or deterioration of the particle level. However, according to the present embodiment, the surface of the substrate W can be stably maintained horizontally, and a desirable processing result can be obtained.

[0045] (1) Adjustment of the inclination of the pedestal 30 with respect to the horizontal plane (leveling of the pedestal 30), (2) adjustment of the inclination of the base portion 22 with respect to the horizontal plane (leveling of the base portion 22), (3) adjustment of the inclination of the substrate W with respect to the horizontal plane (leveling of the substrate W), and (4) adjustment of the height of the surface of the IPA paddle on the surface of the substrate W (adjustment of the height of the substrate). It is preferable to perform all of these before processing each substrate W. However, it takes a certain amount of time to perform all the adjustments. If too much time is spent on the adjustments, the IPA paddle may dry out, the film thickness of the paddle may become thinner, or the paddle may partially disappear, exposing the surface of the substrate W. In this case as well, pattern collapse or deterioration of the particle level may occur.

[0046] To prevent the above problems from occurring, if a predetermined time has elapsed since the substrate W was carried into the substrate holding portion 20, the adjustments (1) to (4) may be stopped midway, the substrate holding portion 20 may be moved to the processing position, and the supercritical drying process may be started. In this case, the remaining adjustments may be made when the next substrate W is carried into the substrate holding portion 20. That is, for example, if a predetermined time has elapsed when the adjustments (1) and (2) for the first substrate W are completed, the adjustments may end at that time, and the adjustments (3) and (4) may be made for the second substrate W.

[0047] As a first modified embodiment, a suction pad 70 may be provided on the upper surface of the base portion 22 at the position shown in FIG. 5. The position where the suction pad 70 is disposed can be, for example, near the irradiation position on the lower surface of the substrate W of the second distance measuring sensor 52 in a plan view. Note that since there is a through hole (the position of 52p in FIG. 3) for passing the detection light from the second distance measuring sensor 52 in the central portion of the base portion 22, three suction pads 70 are disposed so as to surround this through hole. When the suction pad 70 is provided, the horizontal feeding and height adjustment of the substrate can be performed according to the following procedure. That is, first, the support pins 26 are raised and lowered based on the detection result by the second distance measuring sensor 52 to perform the horizontal feeding of the substrate W. At this time, if the displacement of the substrate W corresponding to the amount of raising and lowering of the support pins 26 is not detected by the second distance measuring sensor 52, it is determined that the substrate W is aligned. Then, the substrate W may be closely attached to the support pin 26 by adsorbing the substrate W using the suction pad 70 closest to the support pin 26 where the displacement of the substrate W corresponding to the amount of raising and lowering of the support pin 26 is not recognized. By doing so, the height adjustment of the substrate W by the support pin 26 becomes possible.

[0048] For example, each suction pad 70 may be provided so as to be vertically movable with respect to the base portion 22. By doing so, in addition to the horizontal feeding and height adjustment of the substrate W, the correction of the warp of the substrate W can also be performed. In this case, the suction pad 70 can be attached to the base portion 22 via, for example, a linear actuator (not shown). In this case, the above-described third step and fourth step can be performed by adjusting the height of each suction pad 70.

[0049] When the substrate W is always adsorbed by the suction pad 70 regardless of the degree of warp of the substrate W, the support pins 26 may not be provided. When determining whether to use the suction pad 70 according to the degree of warp of the substrate W, for example, the height of the support pins 26 may be lowered when using the suction pad 70.

[0050] As a second and third modified embodiment, a device (lid inclination detection device) may be provided that indirectly detects the inclination of the base portion 22 with respect to the horizontal plane by detecting the inclination of the lid body 24 integrated with the base portion 22.

[0051] The configuration of the second modified embodiment is shown in FIGS. 6 and 7. The second modified embodiment includes a plurality of fifth distance measuring sensors 55 as a lid inclination detection device. The fifth distance measuring sensor 55 can be an optical distance measuring sensor using infrared rays, lasers, or the like, similar to the first to fourth distance measuring sensors 51 to 54, and is fixed to the machine frame 40 itself or a sensor holding body (not shown) fixed to the machine frame 40. When the substrate holding portion 20 is located at the processing position as shown in FIG. 6, the fifth distance measuring sensor 55 irradiates sensor light to a plurality (preferably three or more, four in the illustrated example) of irradiation positions 55p set on the front surface 24F (which is a vertical plane) of the lid body 24. Based on the distance between each distance measuring sensor 55 and the irradiation position 55p, the coordinates of each irradiation position 55p can be specified, and based on this, the inclination of the lid body 24 can be detected. By setting three or more irradiation positions 55p, the inclination regarding an arbitrary direction of the lid body 24 can be detected.

[0052] The configuration of the third modified embodiment is shown in FIGS. 8 and 9. The third modified embodiment has one or more tilt sensors 56 as lid tilt detection devices. When the tilt sensor 56 is a multi-axis sensor (capable of detecting angular positions around two or more axes facing different directions), the number of tilt sensors 56 may be one. In this case, the tilt sensor 56 (56F) can be provided, for example, on the front surface 24F of the lid 24. When the tilt sensor 56 is a uniaxial sensor (capable of detecting an angular position around only one axis), the tilt sensor 56 can be provided on two surfaces of the lid 24 facing different directions (for example, the front surface 24F and the side surface 24S (which is perpendicular to the front surface 24F)). When the tilt sensor 56 (56S) is provided on the side surface 24S, it is preferable that when the substrate holding portion 20 is in the processing position, the lid 24 protrudes forward from the front surface of the processing container 10 so that the side surface 24S of the lid 24 is not covered by the processing container 10.

[0053] According to the above second and third modified embodiments, during the drying process of the substrate W or immediately before the start of the drying process when the substrate holding portion 20 is in the processing position, the tilt of the base portion 22 can be detected based on the tilt of the lid 24. For this reason, for example, when an inappropriate interference occurs between the substrate holding portion 20 and the processing container 10 and the base portion 22 (that is, the substrate W thereon) tilts, it is possible to detect that such an event has occurred. When an abnormal tilt of the base portion 22 is detected, the control unit 100 may generate an alarm to notify the operator that an abnormality has occurred, or may stop the operation of the supercritical drying apparatus 1.

[0054] It should be considered that all the embodiments disclosed this time are illustrative and not restrictive in any way. The above embodiments may be omitted, replaced, or changed in various forms without departing from the scope and gist of the appended claims.

[0055] The substrate W is, for example, a semiconductor wafer, but is not limited thereto and may be other substrates (ceramic substrates, glass substrates) used in the field of semiconductor device manufacturing.

Explanation of Symbols

[0056] W substrate 10 Processing container 20 Substrate holding part 22 Base part 51 First detection part

Claims

1. A substrate processing apparatus for drying a substrate having a liquid film formed on a pattern formation surface using a supercritical fluid, comprising: a processing vessel for accommodating the substrate and supplying the supercritical fluid; a substrate holding unit having a base portion for supporting the substrate from below with the pattern formation surface facing upward, and holding the substrate in the processing vessel; and the processing vessel has an opening for accommodating the substrate; the substrate holding unit includes a lid connected to the base portion and closing the opening; and an inclination sensor provided on the lid for detecting an inclination of the base portion with respect to a horizontal plane; A substrate processing apparatus.

2. The substrate holding unit is movable forward and backward between a processing position and a retracted position, when the substrate holding unit is in the processing position, the lid closes the opening and the base portion is accommodated in the processing vessel, when the substrate holding unit is in the retracted position, the lid opens the opening and the base portion exits the processing vessel. The substrate processing apparatus according to Claim 1.

3. The substrate processing apparatus according to Claim 1, wherein the inclination sensor is provided at a portion of the front surface of the lid or the side surface of the lid that is not covered by the processing vessel.

4. The substrate processing apparatus according to Claim 1, further comprising a posture adjustment mechanism for adjusting an inclination of the base portion with respect to a horizontal plane.

5. The substrate processing apparatus according to Claim 1, wherein the inclination sensor is provided so as to be able to detect an inclination of the base portion based on an inclination of the lid immediately before starting a drying process of a substrate when the substrate holding unit is in the processing position.

6. The substrate processing apparatus according to Claim 1, wherein the inclination sensor is provided so as to be able to detect an inclination of the base portion based on an inclination of the lid during a drying process of a substrate when the substrate holding unit is in the processing position.

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