Substrate processing apparatus and substrate processing method

Abstract

To provide a wafer processing device capable of processing a wafer at a desired etching rate while maintaining a process liquid at a desired temperature by measuring a temperature of the process liquid and controlling a temperature of a heating section in accordance with the measured temperature, and a wafer processing method.SOLUTION: A wafer processing device 1 comprises: a rotor 10 which rotates a wafer W; a supply section 40 which supplies a process liquid L; a plate 50 which is movable in a direction proximate to / separate from the wafer W; a heating section 60 which heats the process liquid L; a thermometer 70 which is stored in an installation hole 51 of the plate 50 and measures a temperature of the process liquid L supplied to a processed face of the wafer W in a non-contact manner; an air supply port 52 which is opened at a lower side of the thermometer 70 on an inner sidewall of the installation hole 51 and supplies an inert gas G to a lower side of the thermometer 70; an exhaust port 55 which is opened at the lower side of the thermometer 70 and exhausts the inert gas G supplied from the air supply port 52; and a control section 90 which controls the heating section 60 in accordance with the temperature measured by the thermometer 70.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a substrate processing apparatus and a substrate processing method. [Background Art]

[0002] As a wet etching apparatus that etches a film laminated on a substrate such as a semiconductor wafer with a processing liquid, there exists a batch-type substrate processing apparatus that immerses a plurality of substrates in the processing liquid all at once. Such a batch-type substrate processing apparatus can process a plurality of substrates collectively, and thus has high productivity.

[0003] However, since a batch-type substrate processing apparatus immerses a plurality of substrates in a processing liquid under common conditions, it is difficult to finely adjust the etching depth and the like for each substrate in accordance with differences such as the film thickness formed on each substrate. Accordingly, a single-wafer-type substrate processing apparatus that processes substrates one by one is used, in which while rotating a substrate, a processing liquid for etching is supplied near the rotation center of the substrate to spread the processing liquid over the surface of the substrate.

[0004] As the processing liquid for etching, acid-based liquids such as hydrofluoric acid, phosphoric acid, and sulfuric acid are used. For example, when etching a nitride film on a substrate on which an oxide film and a nitride film are laminated, there is a substrate processing apparatus that uses an aqueous solution of phosphoric acid (phosphoric acid solution) as the processing liquid. The higher the temperature of the phosphoric acid solution, the higher the etching performance thereof; when the temperature of the phosphoric acid solution decreases, the etching performance deteriorates. Therefore, to obtain a desired etching rate, the phosphoric acid solution must be maintained at a high temperature. For example, the nitride film is etched by heating a phosphoric acid solution to 150°C to 160°C and supplying it to the substrate.

[0005] However, substrates such as silicon wafers have high thermal conductivity. As a result, the phosphoric acid solution supplied to the surface of the substrate loses heat through the substrate, causing its temperature to drop easily. In other words, the phosphoric acid solution supplied near the center of rotation of the substrate will be hot near the center of rotation, but as it moves towards the outer edge of the substrate, its temperature will decrease due to heat dissipation.

[0006] As described above, if the temperature of the phosphoric acid solution differs depending on the location on the substrate surface, differences in etching rates will occur depending on the location on the substrate surface, making it difficult to process the entire substrate uniformly. To address this, there is a substrate processing apparatus that performs etching while maintaining the temperature of the phosphoric acid solution on the substrate surface (see Patent Document 1).

[0007] This substrate processing apparatus has a heater plate positioned above the substrate surface, large enough to cover the substrate surface. The heater plate is brought close to the substrate surface, and a high-temperature phosphoric acid solution is supplied from a discharge port located near the center of the heater plate. The distance between the substrate and the heater plate is only a few millimeters, and the phosphoric acid solution flows over the substrate surface while being heated. This ensures that the etching performance of the phosphoric acid solution is maintained. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Patent No. 5841431 [Overview of the project] [Problems that the invention aims to solve]

[0009] In substrate processing apparatuses using heater plates as described above, it is necessary to maintain the temperature of the processing solution at a desired temperature during processing in order to obtain the desired etching rate. Conventionally, the temperature of the heater plate was measured, and the temperature of the heater plate was controlled according to the measured temperature to maintain the temperature of the processing solution. However, measuring the temperature of the heater plate does not measure the temperature of the processing solution, so it is not possible to know precisely whether the processing solution is maintaining the desired temperature.

[0010] One type of thermometer used to measure the temperature of the processing solution is a radiation thermometer, which measures temperature non-contact using infrared radiation. However, since the substrate being processed is covered by a heater plate, it is difficult to measure the temperature of the processing solution remotely. To address this, one could consider placing a thermometer on the side of the heater plate that faces the substrate. However, such a thermometer would be in close proximity to the processing solution, and the high-temperature vapor from the processing solution would come into contact with the thermometer, potentially damaging it. This would result in inaccurate temperature measurements or even make temperature measurement impossible, making it difficult to achieve the desired temperature for the processing solution.

[0011] Embodiments of the present invention have been proposed to solve the above-mentioned problems, and their objective is to provide a substrate processing apparatus and a substrate processing method that can process a substrate at a desired etching rate by measuring the temperature of the processing liquid and controlling the temperature of the heating section according to the measured temperature, thereby maintaining the processing liquid at a desired temperature. [Means for solving the problem]

[0012] The substrate processing apparatus according to an embodiment of the present invention includes: a rotating body for rotating a substrate held by a holding unit; a supply unit for supplying a heated processing liquid to the surface of the substrate to be processed; a plate provided at a position opposite to the surface of the substrate and movable in a direction toward and away from the substrate; a drive unit for moving the plate forward and backward relative to the substrate; a heating unit provided on the plate for heating the processing liquid supplied to the surface of the substrate to be processed; a thermometer housed in an installation hole formed in the plate and opening toward the surface of the substrate to be processed, for non-contact measurement of the temperature of the processing liquid supplied to the surface of the substrate to be processed; an air inlet opening on the inner wall of the installation hole below the thermometer and for supplying inert gas below the thermometer; an exhaust port at a different position on the inner wall of the installation hole from the air inlet and opening below the thermometer, for discharging the inert gas supplied from the air inlet; and a control unit for controlling the heating unit according to the temperature measured by the thermometer.

[0013] The substrate processing method of an embodiment of the present invention involves a rotating body rotating a substrate held by a holding unit, supplying inert gas from an air intake port provided in an installation hole opening on the substrate side, and discharging the inert gas from an exhaust port provided in the installation hole, bringing the plate closer to the substrate, supplying heated processing liquid to the substrate surface of the substrate, heating the processing liquid by a heating unit provided on the plate, measuring the temperature of the processing liquid non-contact with a thermometer housed in the installation hole and positioned above the air intake port and exhaust port, and controlling the heating unit according to the temperature measured by the thermometer. [Effects of the Invention]

[0014] Embodiments of the present invention provide a substrate processing apparatus and a substrate processing method that can process a substrate at a desired etching rate by measuring the temperature of the processing solution and controlling the temperature of the heating section according to the measured temperature, thereby maintaining the processing solution at a desired temperature. [Brief explanation of the drawing]

[0015] [Figure 1] It is a diagram showing the configuration of the substrate processing apparatus according to the embodiment. [Figure 2] It is an axial sectional view showing the internal structure of a plate in which a thermometer is accommodated in the installation hole of Fig. 1. [Figure 3] It is a flowchart showing the processing procedure of the substrate processing apparatus according to the embodiment. [Figure 4] It is a sectional view showing a comparative example of a plate accommodating a thermometer. [Figure 5] It is a sectional view showing a modified example of a plate in which a thermometer is accommodated in an installation hole. [Figure 6] It is an explanatory diagram showing a modified example of supply and exhaust control for inert gas. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0016] Hereinafter, embodiments of the present invention will be described with reference to the drawings. [Summary] As shown in Fig. 1, the substrate processing apparatus 1 of the present embodiment processes the surface to be processed of a substrate W by supplying a processing liquid L heated in a supply unit 40 to one surface of the substrate W (hereinafter referred to as the surface to be processed) while rotating the substrate W together with a rotating body 10. At this time, as shown in Fig. 2, a driving unit 80 causes a plate 50 having a heating unit 60 (heater 61) to approach the surface to be processed of the substrate W, narrowing the space between the plate 50 and the substrate W. This makes it difficult for heat to escape, heats the space, and suppresses the temperature drop of the processing liquid L. The plate 50 is not in contact with the substrate W and can move forward and backward relative to the substrate W.

[0017] Note that the substrate W processed according to the present embodiment is, for example, a silicon wafer on which a nitride film is formed, and a phosphoric acid solution for etching the nitride film is used as the processing liquid L.

[0018] [Configuration] A substrate processing apparatus 1, as shown in FIG. 1 and FIG. 2, comprises a rotating body 10, a rotating mechanism 20, a holding portion 30, a supply portion 40, a plate 50, a heating portion 60, a thermometer 70, a driving portion 80, and a control portion 90.

[0019] (Rotating Body) The rotating body 10 rotates the substrate W held by the holding portion 30. The rotating body 10 has a table 11 that faces the substrate W held by the holding portion 30 with a gap therebetween. The rotating body 10 has a cylindrical shape with one end closed by the table 11. The table 11 is a circular surface having a diameter larger than that of the substrate W.

[0020] The rotating body 10 is formed of a material having resistance to the processing liquid L. For example, the rotating body 10 is preferably formed of a fluorine-based resin such as PTFE or PCTFE. Although not shown in the drawings, such a rotating body 10 is rotatably provided on a fixed base fixed to an installation surface or a frame installed on the installation surface by a rotating mechanism 20 described later.

[0021] A separator 12 and a cup 13 are provided around the rotating body 10. The separator 12 and the cup 13 are cylindrical bodies bent such that the diameter of the upper portion thereof is narrowed, and are arranged concentrically with the separator 12 on the inner side and the cup 13 on the outer side. Drain ports 12a and 13a for draining the processing liquid L are respectively provided on bottom surfaces of the separator 12 and the cup 13. The separator 12 and the cup 13 receive various processing liquids L scattered from the rotating substrate W from the periphery of the substrate W. The processing liquid L received by the separator 12 is discharged to a recovery path (not shown) through the drain port 12a, and the processing liquid L received by the cup 13 is discharged to a drain path (not shown) through the drain port 13a.

[0022] (Rotating Mechanism) The rotating mechanism 20 is a mechanism that rotates the rotating body 10. The rotating mechanism 20 has a drive source 21. The drive source 21 teethIt is a hollow motor fixed to a fixed base, having a hollow rotor and a stator that rotates it. The drive source 21 rotates the rotating body 10 together with the rotor by energizing the coils of the stator.

[0023] (holding part) The holding portion 30 holds the substrate W parallel to and spaced apart from the table 11. The holding portion 30 has holding pins 31. The holding pins 31 move between a holding position in contact with the edge of the substrate W and a release position away from the edge of the substrate W by an eccentric rotation about an axis parallel to the axis of the rotating body 10 by a drive mechanism (not shown), thereby releasing the substrate W.

[0024] (Supply Department) As shown in Figure 1, the supply unit 40 supplies the processing liquid L to the surface of the substrate W to be processed, that is, the surface of the substrate W held by the holding unit 30 that is opposite to the table 11. The supply unit 40 has processing liquid supply mechanisms 411 and 412 that supply two types of processing liquid L.

[0025] The processing liquid supply mechanism 411 supplies an aqueous solution containing phosphoric acid (H3PO4) (hereinafter referred to as phosphoric acid solution) as the processing liquid L. The processing liquid supply mechanism 412 supplies pure water (H2O) as the processing liquid L. The processing liquid supply mechanisms 411 and 412 each have a processing liquid tank 41a for storing their respective processing liquids L.

[0026] Each processing liquid tank 41a is connected to a processing liquid supply pipe 41b. The tip of the processing liquid supply pipe 41b faces the substrate W held by the holding part 30. As a result, the processing liquid L from each processing liquid tank 41a is supplied to the surface of the substrate W via the processing liquid supply pipe 41b.

[0027] Each processing liquid supply pipe 41b is equipped with a valve 41c and a flow meter 41d. The valve 41c has a flow rate adjustment function and an ON / OFF function. Each valve 41c adjusts the amount of processing liquid L flowing from the corresponding processing liquid tank 41a into the processing liquid supply pipe 41b. The amount of processing liquid L flowing through each processing liquid supply pipe 41b is detected by the corresponding flow meter 41d. The equipment and method for generating the processing liquid L stored in each processing liquid tank 41a are not limited to any specific type.

[0028] (plate) The plate 50 is positioned opposite the surface of the substrate W to be processed and is a movable component that moves toward and away from the substrate W. The plate 50 is circular in diameter and larger than the substrate W. A flange 50b that expands outward is formed on the upper periphery of the plate 50. The plate 50 is made of quartz. The plate 50 may have a double-layer structure to achieve both heat resistance and liquid resistance. That is, a base material is formed from a heat-resistant material, and its periphery is covered with a material resistant to the processing liquid L. For example, the plate 50 may be constructed by using quartz as the base material and forming a cover of a fluorine-based resin such as PTFE or PCTFE around it.

[0029] The plate 50 has two discharge ports 50a, through which the tips of two processing liquid supply pipes 41b are inserted and which are exposed to the substrate W side. The two discharge ports 50a are offset from the axis of rotation of the rotating body 10. This is because, as the substrate W rotates, the portion of the substrate W facing the discharge ports 50a changes sequentially, which contributes to the uniformity of the temperature of the processing liquid L. Furthermore, as will be described later, the plate 50 is provided with mounting holes 51, an air intake port 52, and an exhaust port 55.

[0030] (heating part) The heating unit 60 is provided on the plate 50 and heats the processing liquid L supplied to the surface of the substrate W to be processed. In this embodiment, the heating unit 60 is a heater 61 that generates heat when an electric current is applied. Multiple heaters 61 are provided at different horizontal positions on the plate 50. For example, the heater 61 is composed of, for example, three heater pieces, whose heat generation can be individually controlled. That is, two annular heater pieces are arranged concentrically around a circular heater piece. With such a heater 61, the temperature of the processing liquid L can be changed for each concentric section by individually controlling the heat generation of the three concentrically arranged heater pieces. The diameter of the heating unit 60 is preferably equal to or larger than the diameter of the substrate W in order to suppress the temperature drop on the outer circumference of the substrate W.

[0031] (thermometer) The thermometer 70 measures the temperature of the processing liquid L supplied to the surface of the substrate W to be processed in a non-contact manner. The thermometer 70 is housed in a mounting hole 51 formed in the plate 50. The mounting hole 51 is a cylindrical through hole. The mounting hole 51 penetrates the plate 50 in the thickness direction (vertical direction). The thermometer 70 is inserted into the upper end of the mounting hole 51. The end of the mounting hole 51 on the side facing the surface to be processed is an opening 51a. As the thermometer 70, for example, a radiation thermometer is used that measures temperature based on the amount of infrared radiation emitted by the object to be measured. The detection surface of the thermometer 70 faces the surface to be processed so that it can sense infrared radiation through the opening 51a of the mounting hole 51.

[0032] Multiple thermometers 70 are provided at different radial positions on the plate 50. That is, multiple mounting holes 51 are provided at different radial positions on the plate 50, and a thermometer 70 is installed in each mounting hole 51. For example, three mounting holes 51 are provided corresponding to three heater pieces, and a thermometer 70 is inserted into the upper end of each. Below the thermometer 70 in the mounting hole 51, a space 51b is formed for accumulating inert gas G.

[0033] Each installation hole 51 has an air intake port 52 and an exhaust port 55 on its inner wall. The air intake port 52 opens below the thermometer 70 and supplies inert gas G to the space 51b below the thermometer 70. The plate 50 is provided with an air supply passage 53 for supplying inert gas G to the air intake port 52. An air supply unit 54 is connected to the air supply passage 53. The air supply unit 54 includes an air supply device 54a and a mass flow controller (hereinafter referred to as MFC) 54b, and is connected to the air supply passage 53 via piping (not shown).

[0034] The air supply device 54a is a source of inert gas G. It is preferable to use helium (He) as the inert gas G. Since the specific gravity of He is lighter than that of water vapor (H2), He is located above the water vapor (hereinafter referred to as steam V) that enters through the opening 51a and rises towards the thermometer 70. Therefore, He is interposed between the steam V rising from the processing liquid L and the thermometer 70, protecting the thermometer 70. However, N2 may also be used as the inert gas G.

[0035] The MFC54b is installed in the piping connected between the air supply device 54a and the air supply passage 53, and is an adjustment unit that adjusts the supply flow rate of the inert gas G per unit time. The MFC54b has a mass flow meter for measuring the fluid flow rate and a solenoid valve for controlling the flow rate.

[0036] The exhaust port 55 opens below the thermometer 70 and is located at a different position from the air intake port 52, and discharges the inert gas G supplied from the air intake port 52. Different positions include positions that do not overlap in a plan view and / or positions that are at different heights. In this embodiment, the exhaust port 55 is located opposite the air intake port 52, with the thermometer 70 in between, in a plan view. As a result, the inert gas G supplied from the air intake port 52 passes through so as to cover the detection surface of the thermometer 70 and is discharged from the exhaust port 55. The exhaust port 55 is also located on the opening 51a side (below the air intake port 52) ​​than the air intake port 52. It is preferable that the air intake port 52 is installed at a distance from the bottom of the thermometer 70. As a result, the inert gas G supplied from the air intake port 52 flows downward towards the exhaust port 55, which is located on the opening 51a side, making it more difficult for steam V to enter from the opening 51a.

[0037] In this embodiment, as shown in Figures 1 and 2, the air inlet 52 located below the thermometer 70 is spaced vertically apart from the thermometer 70. This creates a space (retention space) below the thermometer 70 in the installation hole 51 where the inert gas G, which has a low specific gravity, can accumulate when supplied from the air inlet 52. In this way, the accumulation of inert gas G below the thermometer 70 protects the thermometer 70 from vapor V. To clarify the retention space within the installation hole 51 in Figure 2, the vertical spacing of the retention space is indicated by RS.

[0038] Furthermore, in this embodiment, as shown in Figures 1 and 2, the air intake port 52 and the exhaust port 55 are positioned in the installation hole 51 closer to the thermometer 70. In other words, in the vertical direction, the distance between the air intake port 52 and the opening 51a is greater than the distance between the air intake port 52 and the thermometer 70. Thus, because the exhaust port 55 is positioned lower than the air intake port 52, and the exhaust port 55 is positioned closer to the thermometer 70 in the installation hole 51, the space from the bottom of the exhaust port 55 to the opening 51a is larger than the space from the bottom of the exhaust port 55 to the thermometer 70. As a result, the supply of inert gas G from the air intake port 52 and the discharge of inert gas G from the exhaust port 55 result in only a small gas flow in the space below the exhaust port 55. This prevents steam V from entering through the opening 51a, protecting the thermometer 70 from steam. To clarify the upper and lower spaces within the installation hole 51 in Figure 2, the vertical distance from the bottom of the exhaust port 55 to the opening 51a is indicated by LS, and the vertical distance from the bottom of the exhaust port 55 to the thermometer 70 is indicated by US.

[0039] The plate 50 is provided with an exhaust passage 56 for exhausting inert gas G from an exhaust port 55. An exhaust unit 57 is connected to the exhaust passage 56. The exhaust unit 57 includes an exhaust device 57a and a mass flow controller (hereinafter referred to as MFC) 57b, and is connected to the exhaust passage 56 via piping (not shown).

[0040] The exhaust device 57a is a device that draws in an inert gas G. The MFC 57b is installed in the piping connected between the exhaust device 57a and the exhaust passage 56, and is an adjustment unit that adjusts the exhaust flow rate per unit time by the exhaust device 57a. The MFC 57b has a mass flow meter for measuring the fluid flow rate and a solenoid valve for controlling the flow rate.

[0041] The drive unit 80 is a mechanism that moves the plate 50 forward and backward relative to the substrate W. The drive unit 80 has a support unit 81, an arm 82, and a lifting mechanism 83. The support unit 81 is a ring-shaped member through which the plate 50 is inserted, and a flange 50b abuts against the upper part of the support unit 81, thereby supporting the plate 50 horizontally. The arm 82 is a horizontally extending member with one end fixed to the support unit 81.

[0042] The lifting mechanism 83 is erected on a frame and is a mechanism that raises and lowers the plate 50 via an arm 82. The lifting mechanism 83 has a movable part that moves in a direction parallel to the axis of the rotating body 10, and the other end of the support part 81 is attached to the movable part. Various mechanisms for moving the movable part can be applied to the lifting mechanism 83, such as a cylinder or a ball screw mechanism, but the details are omitted. The lifting mechanism 83 lowers the plate 50 to a position where a gap d is formed between it and the surface of the substrate W. This gap d is, for example, 4 mm or less, but is maintained so that there is a gap of about 2 mm between it and the processing liquid L.

[0043] The processing liquid L is heated to a preset temperature by a heating device (not shown) in the supply unit 40, and then supplied to the substrate W and heated by the heating unit 60. This allows the processing liquid L supplied to the substrate W to spread across the entire surface of the substrate W while maintaining the preset temperature. In particular, by making the heater 61 on the outer periphery side high temperature, the effect of raising the temperature of the outer periphery side of the substrate W, which tends to cool down easily, can be obtained.

[0044] (Control Unit) The control unit 90 controls each part of the substrate processing apparatus 1. The control unit 90 has a processor that executes programs to realize various functions of the substrate processing apparatus 1, a memory that stores various information such as programs and operating conditions, and drive circuits that drive each element. In other words, the control unit 90 has a mechanism control unit 91 that controls the rotating mechanism 20, the holding unit 30, the supply unit 40, MFCs 54b and 57b, the heating unit 60, the drive unit 80, and so on.

[0045] Furthermore, the control unit 90 of this embodiment includes a heating control unit 92 and a flow rate control unit 93. The heating control unit 92 controls the temperature of the heating unit 60 according to the temperature measured by the thermometer 70. In other words, the heating control unit 92 performs feedback control, which controls the output of the heater 61 according to the temperature of the processing liquid L. For example, if the temperature measured by the thermometer 70 is lower than a predetermined temperature, the temperature of the heater 61 corresponding to that thermometer 70 is increased. For example, each thermometer 70 corresponds to a heater 61 adjacent to the center side of the plate 50.

[0046] The flow rate control unit 93 controls the supply and exhaust flow rates of inert gas G to the installation hole 51 using MFCs 54b and 57b, so that the installation hole 51 is filled with inert gas G but does not leak out from the opening 51a. If the supply flow rate of inert gas G is too high, it will leak from the installation hole 51 and the temperature of the processing liquid L will decrease. If the exhaust flow rate of inert gas G is too high, it will draw in vapor V, affecting the thermometer 70 and drawing in the surrounding atmosphere on the surface of the substrate W to be processed, which will lower the temperature of the processing liquid L. For this reason, it is basically preferable to control the supply flow rate and exhaust flow rate of inert gas G to be equal.

[0047] [Operation] The operation of the substrate processing apparatus 1 of this embodiment, as described above, will be explained with reference to the flowchart in Figure 3, in addition to Figures 1 and 2 above. Note that a substrate processing method and a processed substrate manufacturing method that process the substrate W according to the following procedure are also aspects of this embodiment.

[0048] First, as shown in Figure 1, the plate 50 is in an upper standby position. At this time, a gap is provided between the plate 50 and the table 11 that allows a substrate W, supported by the hand of a transport robot (not shown), to be loaded.

[0049] Furthermore, by pre-energizing the heater 61 of the heating unit 60, the surface of the plate 50 facing the substrate W is heated and maintained at a predetermined temperature (for example, a temperature within the temperature range of 180°C to 225°C). For example, since the outer peripheral region of the substrate W is the lowest in temperature due to heat dissipation, the heater 61 in the outer peripheral region may be heated to a higher temperature than in other regions.

[0050] In this state, the substrate W mounted on the hand of the transport robot is moved between the plate 50 and the rotating body 10, and its periphery is supported by a plurality of retaining pins 31, thereby being held on the table 11 of the rotating body 10 (step S01). At this time, the substrate W is positioned so that its center aligns with the axis of rotation of the rotating body 10.

[0051] The air supply unit 54 starts supplying inert gas G from the air inlet 52 to the installation hole 51, thereby filling the space 51b with inert gas G (step S02). Next, the exhaust unit 57 starts exhausting the inert gas G from the exhaust port 55 (step S03). The MFCs 54b and 57b adjust the supply flow rate and exhaust flow rate of the inert gas G so that inert gas G is always present in the space 51b and does not leak out from the opening 51a.

[0052] The rotating body 10 rotates at a relatively low predetermined speed (for example, about 50 rpm). As a result, the substrate W rotates together with the holding part 30 at the predetermined speed (step S04). Then, the plate 50 descends to a position where a predetermined gap d (for example, 4 mm or less) is formed between it and the surface of the substrate W to be processed (step S05). 。

[0053] The processing liquid supply mechanism 411 supplies the phosphoric acid solution to the surface of the substrate W to be processed, and the thermometer 70 begins measuring the temperature of the phosphoric acid solution (step S06). Temperature measurement is performed continuously while the phosphoric acid solution is being supplied. As described above, the phosphoric acid solution is preheated in the supply unit 40. As the phosphoric acid solution moves sequentially toward the outer circumference of the rotating substrate W, the pure water on the surface of the substrate W is replaced by the phosphoric acid solution, and the nitride film is removed by etching.

[0054] As the phosphoric acid solution supplied to the center of the substrate W moves toward the outer periphery of the substrate W, heat dissipates more easily. However, in this embodiment, since the plate 50 is close to the substrate W, with a gap d between them, the phosphoric acid solution is heated by the heater 61, suppressing a decrease in the processing rate due to a drop in temperature. For example, it is preferable to maintain the temperature of the phosphoric acid solution at around 150-160°C.

[0055] The temperature of the phosphoric acid solution during processing is measured by the thermometer 70 as described above. The heating control unit 92 controls the temperature of the heater 61 according to the measured temperature. In other words, it raises the temperature of the heater 61 in the area where the temperature is decreasing. Because the space 51b of the mounting hole 51 is filled with inert gas G, the detection surface of the thermometer 70 is covered with inert gas G, so that vapor V from the heated phosphoric acid solution does not adhere to the detection surface. This allows the liquid temperature to be measured normally while maintaining the performance of the thermometer 70. In addition, since the inert gas G does not leak out from the opening 51a, the temperature of the phosphoric acid solution is not lowered by the inert gas G.

[0056] When a predetermined processing time has elapsed (step S07), the processing liquid supply mechanism 411 stops supplying the phosphoric acid solution, and the thermometer 70 also stops measuring the temperature (step S08).

[0057] Next, the processing liquid supply mechanism 412 supplies pure water to the surface of the substrate W (step S09). As pure water is supplied to the surface of the rotating substrate W, the pure water moves sequentially toward the outer edge of the substrate W, washing away the phosphoric acid solution from the surface of the substrate W. Then, after a predetermined washing time has elapsed (step S10), the processing liquid supply mechanism 412 stops supplying pure water (step S11).

[0058] The substrate W stops rotating (step S12), and the plate 50 rises (step S13). Subsequently, the supply of inert gas G by the air supply unit 54 and the exhaust by the exhaust unit 57 are stopped. ru ( Step S14) 。 Then, the hand of the transport robot is inserted under the substrate W, the holding part 30 releases the substrate W, and the substrate W is unloaded by the hand of the transport robot (step S15).

[0059] [effect] (1) The substrate processing apparatus 1 of this embodiment, as described above, includes a rotating body 10 that rotates the substrate W held by the holding part 30, a supply part 40 that supplies heated processing liquid L to the surface of the substrate W to be processed, a plate 50 provided at a position opposite to the surface of the substrate W and movable in a direction toward and away from the substrate W, a drive part 80 that moves the plate 50 forward and backward relative to the substrate W, a heating part 60 provided on the plate 50 that heats the processing liquid L supplied to the surface of the substrate W to be processed, and an installation formed on the plate 50 that opens toward the surface of the substrate to be processed The device includes a thermometer 70 housed in a hole 51 for non-contact measurement of the temperature of the processing liquid L supplied to the surface of the substrate W to be processed; an air inlet 52 opening below the thermometer 70 on the inner wall of the installation hole 51 for supplying inert gas G below the thermometer 70; an exhaust port 55 located at a different position from the air inlet 52 on the inner wall of the installation hole 51, opening below the thermometer 70 for discharging the inert gas G supplied from the air inlet 52; and a control unit 90 that controls the heating unit 60 according to the temperature measured by the thermometer 70.

[0060] In this embodiment of the substrate processing method, the rotating body 10 rotates the substrate W held by the holding part 30, and supplies inert gas G from an air supply port 52 provided in an installation hole 51 that opens on the side of the substrate W and is positioned opposite the surface of the substrate W to be processed, and exhausts the inert gas G from an exhaust port 55 provided in the installation hole 51, bringing the plate 50 closer to the substrate W, the air supply part 54 supplies heated processing liquid L to the surface of the substrate W to be processed, the heating part 60 provided on the plate 50 heats the processing liquid L, the thermometer 70 housed in the installation hole 51 and provided above the air supply port 52 and exhaust port 55 measures the temperature of the processing liquid L non-contact, and the control unit 90 controls the heating part 60 according to the temperature measured by the thermometer 70.

[0061] Therefore, by measuring the temperature of the processing liquid L using a thermometer 70 provided in the mounting hole 51 of the plate 50, and controlling the temperature of the heating unit 60 according to the measured temperature, the processing liquid L can be maintained at a desired temperature, and the substrate W can be processed at a desired etching rate. In particular, the inert gas G in the mounting hole 51 protects the thermometer 70 from vapor V, thereby maintaining the performance of the thermometer 70 that measures the temperature of the processing liquid L, and since the inert gas G in the mounting hole 51 is exhausted, the outflow of the inert gas G from the mounting hole 51 is prevented, and the temperature drop of the processing liquid L can be suppressed.

[0062] Here, for example, as shown in Figure 4(A), if the thermometer 70 is simply placed in the mounting hole 51 formed in the plate 50, vapor V from the processing liquid L will enter through the opening 51a of the mounting hole 51. As a result, the thermometer 70 will be exposed to a high-temperature vapor atmosphere, leading to deformation, damage, and a decrease in measurement accuracy. Furthermore, as shown in Figure 4(B), even if the thermometer 70 is protected by supplying inert gas G to the mounting hole 51 with a gap around it, the temperature of the processing liquid L will decrease due to the inert gas G leaking from the opening 51a, resulting in a decrease in processing performance.

[0063] On the other hand, this embodiment prevents the intrusion of vapor V from the high-temperature processing liquid L into the mounting hole 51 and prevents the leakage of inert gas G from the mounting hole 51, thereby enabling measurement of the temperature of the processing liquid L. In other words, by protecting the thermometer 70 from the vapor V of the processing liquid L by supplying inert gas G, deformation, damage, and deterioration of the measurement performance of the thermometer 70 can be prevented, and performance can be maintained. Furthermore, by exhausting the inert gas G, a drop in the temperature of the processing liquid L due to leakage of inert gas G can be prevented, thereby suppressing a decrease in the processing rate of the substrate W and achieving high process performance and reproducibility.

[0064] In particular, by positioning the air intake port 52 and the exhaust port 55 in different locations, it becomes easier to form a flow that covers the detection surface of the thermometer 70. For example, by positioning the air intake port 52 and the exhaust port 55 so that they do not overlap in a plan view, a flow is created in which the inert gas G supplied from the air intake port 52 passes under the detection surface and heads toward the exhaust port 55, thereby covering the detection surface with the inert gas G. Since the mounting hole 51 that houses the thermometer 70 has a relatively small diameter (for example, about 10 mm), by positioning the air intake and exhaust in this way, the inert gas G can spread across the entire detection surface of the thermometer 70. Furthermore, by supplying the inert gas G to the mounting hole 51, allowing the inert gas G to accumulate in the mounting hole 51, and then exhausting it, a protective layer of inert gas G can be formed.

[0065] (2) Multiple heating units 60 are provided at different radial positions on the plate 50, and multiple thermometers 70 are provided at different radial positions on the plate 50. Therefore, the control unit 90 can adjust the temperature of the heating units 60 according to the differences in the temperature distribution of the processing liquid L on the surface to be processed, thereby preventing a decrease in the processing rate and enabling good processing. The control unit 90 can also change the processing rate according to its position on the surface to be processed.

[0066] (3) The exhaust port 55 is located below the air intake port 52. As a result, an airflow is generated that causes the inert gas G from the air intake port 52 to flow downward, making it difficult for the steam V to rise and preventing the steam V from entering.

[0067] (4) The inert gas G is a gas with a lower specific gravity than the vapor V (water vapor). Therefore, the inert gas G is above the vapor V, and the inert gas G is interposed between the vapor V rising from the processing liquid L on the surface of the substrate W and the thermometer 70, thereby protecting the thermometer 70.

[0068] (5) The air intake port 52 is provided with a vertical gap RS between it and the thermometer 70. As a result, a space is formed below the thermometer 70 in the installation hole 51 where the inert gas G accumulates. Consequently, the thermometer 70 is protected by the layer of inert gas G that accumulates below it.

[0069] (modified version) (1) As shown in Figure 5, the air intake passage 53 may be cylindrical in shape, surrounding the thermometer 70 with a gap. The air intake port 52 may be made into a long horizontal slit to allow the inert gas G to spread more easily across the detection surface of the thermometer 70. Alternatively, the flow velocity of the inert gas G may be increased by making the diameter of the air intake port 52 smaller than the diameter of the air intake passage 53 shown in Figure 2, or by making the gap between the air intake passage 53 and the thermometer 70 narrower at the air intake port 52 than at the air intake passage 53 as shown in Figure 5.

[0070] (2) The air supply unit 54 is provided with a valve that sets the flow rate of the inert gas G to a predetermined amount, a measuring unit provided in the air supply unit 54 that measures the supply flow rate of the inert gas G, and an adjustment unit that adjusts the flow rate of the inert gas G, and the control unit 90 may control the adjustment unit to adjust the exhaust flow rate according to the measurement result from the measuring unit. For example, as shown in Figure 6, a flow meter 54c (measuring unit) and a needle valve 54d (valve) may be provided instead of the MFC 54b of the air supply device 54a. In this case, the needle valve 54d sets the flow rate of the inert gas G to a predetermined amount, and the value measured by the flow meter 54c is input to the control unit 90. The flow rate control unit 93 adjusts the exhaust flow rate using the MFC 57b of the exhaust device 57a so that the flow rate is the same as the input measured value. This simplifies the control configuration and reduces the cost of the device.

[0071] (3) The heating section 60 may have a structure in which each heater 61 includes a heat equalization plate. Alternatively, the heating section 60 may use a device that directly heats the substrate W or the processing liquid L with light such as a halogen lamp or LED. In the above embodiment, a thermometer 70 was provided for each of the multiple heating sections 60 to approximate the area where the temperature was measured with the area being heated, but the number of heating sections 60 and the number of thermometers 70 do not necessarily have to correspond.

[0072] (4) The processing of the substrate processing apparatus 1 is not limited to the examples given above, as long as the temperature of the processing solution L and the substrate W affects the processing rate. The substrate W and film to be processed are also not limited to the examples given above.

[0073] [Other embodiments] Although embodiments and modifications of the present invention have been described above, these embodiments and modifications are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments described above can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the invention described in the claims. [Explanation of Symbols]

[0074] 1. Substrate processing device 10. Solids of revolution 11 Tables 12 Separators 12a, 13a Drain port 13 cups 20 Rotation mechanism 2 1 Power source 30 Holding part 31 Retaining pins 40 Supply section 41a Treatment liquid tank 41b Processing liquid supply pipe 41c valve 41d, 54c flow meter 50 plates 50a outlet 50b flange 51 Installation hole 51a aperture 51b Space 52 Air supply port 53 Air supply path 54 Air supply section 54a Air supply system 54b, 57b MFC 54d Needle Valve 55 Exhaust port 56 Exhaust passage 57 Exhaust section 57a Exhaust system 60 Heating section 61 Heater 70 Thermometer 80 Drive unit 81 Support part 82 Arm 83 Lifting mechanism 90 Control Unit 91 Mechanism Control Unit 92 Heating Control Unit 93 Flow Control Unit 411, 412 Processing liquid supply mechanism

Claims

1. A rotating body that rotates the substrate held by the holding part, A supply unit that supplies heated processing liquid to the surface of the substrate to be processed, A plate provided at a position opposite to the surface to be processed and movable in a direction toward and away from the substrate, A drive unit that moves the plate forward and backward relative to the substrate, A heating unit is provided on the plate for heating the processing liquid supplied to the surface of the substrate to be processed, A thermometer is housed in an installation hole formed in the plate and opening toward the surface to be processed, and measures the temperature of the processing liquid supplied to the surface to be processed of the substrate in a non-contact manner. An air inlet is provided in the inner wall of the installation hole, opening below the thermometer and supplying inert gas below the thermometer, An exhaust port is provided in the inner wall of the installation hole at a position different from the air intake port, opening below the thermometer, and discharging the inert gas supplied from the air intake port. A control unit controls the heating unit according to the temperature measured by the thermometer, A substrate processing apparatus characterized by having

2. Multiple heating units are provided at different positions in the radial direction of the plate. The substrate processing apparatus according to claim 1, characterized in that a plurality of thermometers are provided at different radial positions on the plate.

3. The substrate processing apparatus according to claim 1 or 2, characterized in that the exhaust port is provided below the air intake port.

4. The substrate processing apparatus according to claim 3, characterized in that the air intake port is provided at a vertical distance from the thermometer.

5. The substrate processing apparatus according to claim 4, characterized in that the inert gas is a gas lighter than water vapor.

6. The substrate processing apparatus according to claim 1 or 2, characterized in that it has a cylindrical air intake passage connected to the air intake port and covering the area around the thermometer with a gap.

7. An air supply unit that supplies the inert gas to the air inlet, An exhaust unit that exhausts the inert gas from the exhaust port, A valve provided in the air supply section, which controls the flow rate of the inert gas to a predetermined amount, A measuring unit for measuring the supply flow rate of the inert gas, An adjustment unit is provided in the exhaust section for adjusting the exhaust flow rate of the inert gas, It has, The substrate processing apparatus according to claim 1 or 2, characterized in that the control unit controls the adjustment unit to adjust the exhaust flow rate according to the measurement result from the measurement unit.

8. The rotating body rotates the substrate held by the holding part. A plate is provided at a position opposite the surface of the substrate to be processed, and is movable in a direction toward and away from the substrate. An inert gas is supplied from an air inlet provided in an installation hole that opens on the side facing the surface of the substrate. The inert gas is discharged from the exhaust port provided in the installation hole. The plate is brought close to the substrate, and the supply unit supplies heated processing liquid to the surface of the substrate to be processed. The heating section provided on the plate heats the processing liquid. A thermometer housed within the aforementioned installation hole and positioned above the air intake and exhaust ports measures the temperature of the processing liquid non-contact. The control unit controls the heating unit according to the temperature measured by the thermometer. A substrate processing method characterized by the following:

9. A valve provided in the air supply section that supplies the inert gas to the air inlet controls the flow rate of the inert gas to a predetermined amount. The measuring unit measures the supply flow rate of the inert gas from the air supply unit. The control unit controls the exhaust flow rate of the inert gas by an adjustment unit provided in the exhaust passage that exhausts the inert gas from the exhaust port, according to the measurement results from the measuring unit. The substrate processing method according to claim 8, characterized in that it is a feature of the present invention.

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