JP6397095B2 - Substrate processing equipment - Google Patents

Description

  The present invention relates to a substrate processing apparatus for processing a substrate. Examples of substrates to be processed include semiconductor wafers, liquid crystal display substrates, plasma display substrates, FED (Field Emission Display) substrates, optical disk substrates, magnetic disk substrates, magneto-optical disk substrates, and photomasks. Substrate, ceramic substrate, solar cell substrate and the like.

  In the manufacturing process of semiconductor devices and liquid crystal display devices, the silicon nitride film is selectively removed by supplying a high-temperature phosphoric acid aqueous solution as an etchant to the surface of the substrate on which the silicon nitride film and the silicon oxide film are formed. Etching is performed as necessary. Patent Document 1 discloses a single-wafer type substrate processing apparatus that supplies a phosphoric acid aqueous solution near the boiling point to a substrate held by a spin chuck.

JP 2012-074601

In the substrate processing apparatus of Patent Document 1, a high-temperature phosphoric acid aqueous solution of 100 ° C. or higher is supplied to the substrate. Water gradually evaporates from the phosphoric acid aqueous solution supplied onto the substrate. At that time, reaction of 2H ₃ PO ₄ → H ₄ P ₂ O ₇ + H ₂ O occurs in the phosphoric acid aqueous solution, and pyrophosphoric acid (H ₄ P ₂ O ₇ ) is converted from phosphoric acid (H ₃ PO ₄ ). Generated. Pyrophosphate has the ability to etch the silicon oxide film. Originally, it is desirable to etch only the silicon nitride film and leave as much silicon oxide film as possible without etching. When the etching amount of the silicon nitride film is improved while suppressing the etching amount of the silicon oxide film, the value of the etching selectivity (the etching amount of the silicon nitride film / the etching amount of the silicon oxide film) can be increased. However, when the pyrophosphoric acid is generated, the silicon oxide film originally intended to remain is also etched, so that the etching selectivity is lowered.

  Accordingly, one of the objects of the present invention is to provide a substrate processing apparatus capable of increasing the etching rate (the amount of etching of the silicon nitride film per unit time) and at the same time suppressing the decrease in the etching selectivity. is there.

In order to achieve the above object, the invention according to claim 1 is the substrate holding means for horizontally holding the substrate, the substrate rotating means for rotating the substrate holding means, and the upper surface of the substrate held by the substrate holding means. A phosphoric acid supply means for forming a liquid film of a paddle-shaped phosphoric acid aqueous solution covering the entire upper surface of the substrate by supplying a phosphoric acid aqueous solution to the substrate, and a liquid film of the paddle-shaped phosphoric acid aqueous solution is formed on the substrate Heating means for heating the substrate in a held state, and supplying water to the liquid film of the phosphoric acid aqueous solution at a flow rate capable of maintaining the liquid film of the paddle-like phosphoric acid aqueous solution on the substrate; And a water supply means for maintaining a liquid film of the paddle-like phosphoric acid aqueous solution on the substrate.

  According to a second aspect of the present invention, there is provided a substrate holding means for horizontally holding the substrate, and a paddle covering the entire upper surface of the substrate by supplying a phosphoric acid aqueous solution to the upper surface of the substrate held by the substrate holding means. Phosphoric acid supply means for forming a liquid film of a phosphoric acid aqueous solution, heating means for heating the substrate in a state where the liquid film of the paddle-like phosphoric acid aqueous solution is held on the substrate, and the heating means And a water supply means for supplying water corresponding to the amount of water evaporated from the liquid film of the paddle-like phosphoric acid aqueous solution to the liquid film of the paddle-like phosphoric acid aqueous solution by heating by the substrate processing apparatus. is there.

According to these configurations, the phosphoric acid supply unit supplies the phosphoric acid aqueous solution as the etching solution to the upper surface of the substrate held horizontally by the substrate holding unit. Thereby, a liquid film of a phosphoric acid aqueous solution covering the entire upper surface of the substrate is formed. Then, the substrate is heated by the heating means while the liquid film of the phosphoric acid aqueous solution is held on the substrate. Thereby, phosphoric acid aqueous solution is heated and an etching rate is raised. Further, since the water supply means supplies water (for example, pure water) to the liquid film of the phosphoric acid aqueous solution on the substrate, the phosphoric acid aqueous solution is obtained by the reaction of H ₄ P ₂ O ₇ + H ₂ O → 2H ₃ PO _4. Pyrophosphate (H ₄ P ₂ O ₇ ) in the medium decreases. Since the abundance of pyrophosphoric acid in the phosphoric acid aqueous solution, which is a factor that lowers the etching selectivity, can be suppressed, a decrease in the etching selectivity can be suppressed.

  Furthermore, according to the structure of Claim 2, the quantity of water equivalent to the quantity of the water evaporated from the liquid film of phosphoric acid aqueous solution is supplied to the liquid film of phosphoric acid aqueous solution. That is, water is replenished to the liquid film of the phosphoric acid aqueous solution by the amount evaporated. Therefore, pyrophosphoric acid in the phosphoric acid aqueous solution is reduced, and the concentration change of the phosphoric acid aqueous solution due to the supply of water is substantially prevented. Furthermore, since less water is supplied to the phosphoric acid aqueous solution on the substrate, changes in the concentration and temperature of the phosphoric acid aqueous solution can be suppressed. Thereby, the fluctuation | variation of an etching rate can be suppressed, suppressing the fall of an etching selectivity.

According to a third aspect of the present invention, there is provided a water supply position moving means for moving a water supply position with respect to the substrate in a radial direction of the substrate, a control means for controlling the water supply means, the substrate rotating means, and the water supply position moving means. And when the substrate is held by the substrate rotating means and the substrate is rotated while water is supplied from the water supply means to the liquid film of the phosphoric acid aqueous solution, The substrate processing apparatus according to claim 1, wherein the water supply unit is controlled so that a water supply amount supplied from the water supply unit is larger at a center portion of the substrate than at a peripheral portion of the substrate.
According to a fifth aspect of the present invention, there is provided a substrate rotating means for rotating the substrate holding means, a water supply position moving means for moving a water supply position with respect to the substrate in a substrate radial direction, the water supply means, the substrate rotating means, And a control means for controlling the water supply position moving means, wherein the control means is configured to transfer the phosphoric acid aqueous solution from the water supply means while the substrate held by the substrate holding means is rotated by the substrate rotating means. When the water is supplied to the liquid film, the water supply means is controlled so that the amount of water supplied from the water supply means is larger at the center of the substrate than at the peripheral edge of the substrate. Item 3. The substrate processing apparatus according to Item 2.
According to the structure of Claim 3 and Claim 5, more water per unit area can be supplied toward the upper-surface center part of a board | substrate. Therefore, even if a large amount of water moves to the peripheral edge of the substrate, variation in the concentration of the phosphoric acid aqueous solution film on the substrate in the radial direction of the substrate can be reduced. As a result, the etching rate in the radial direction of the substrate can be reduced. Variation can be suppressed or prevented.
According to a fourth aspect of the present invention, the water supply position moving means for moving the water supply position with respect to the substrate between the central portion of the substrate and the peripheral edge of the substrate, and the control means for controlling the water supply position moving means are further provided. The control means is configured to supply water to the liquid film of the phosphoric acid aqueous solution from the water supply means while the substrate held by the substrate holding means is rotated by the substrate rotation means. 2. The substrate processing apparatus according to claim 1, wherein the water supply position moving unit is controlled such that a movement speed of the water supply position from the second position is slower at a center portion of the substrate than at a peripheral edge portion of the substrate.
According to a sixth aspect of the present invention, there is provided a substrate rotating means for rotating the substrate holding means, a water supply position moving means for moving a water supply position for the substrate between a substrate center portion and a substrate peripheral portion, and the water Control means for controlling the supply position moving means, the control means from the water supply means to the liquid film of the phosphoric acid aqueous solution while the substrate held by the substrate holding means is rotated by the substrate rotating means The water supply position moving means is controlled such that when water is supplied, the movement speed of the water supply position from the water supply means is slower at the center of the substrate than the peripheral edge of the substrate. Item 3. The substrate processing apparatus according to Item 2.
According to the structure of Claim 4 and Claim 6, more water per unit area can be supplied toward the upper-surface center part of a board | substrate. Therefore, even if a large amount of water moves to the peripheral edge of the substrate, variation in the concentration of the phosphoric acid aqueous solution film on the substrate in the radial direction of the substrate can be reduced. As a result, the etching rate in the radial direction of the substrate can be reduced. Variation can be suppressed or prevented.
The invention according to claim 7, wherein the water supply means, comprising said water discharge port for intermittently discharging water toward the upper surface of the substrate held by the substrate holding means, any of claim 1-6 or a substrate processing apparatus according to an item.
In the case of continuous discharge, it is difficult to supply a small amount of water with high accuracy. However, in the case of intermittent discharge and supply as in the invention of claim 4, a small amount of water is relatively high. It can be supplied with accuracy. Since a very small amount of water can be supplied with high accuracy, changes in the concentration and temperature of the phosphoric acid aqueous solution can be more reliably suppressed. Thereby, the fluctuation | variation of an etching rate can be suppressed, suppressing the fall of an etching selectivity.

The invention according to claim 8, wherein the water supply means one by one and discharges the water droplets from the water discharge opening towards the upper surface of the substrate held by the substrate holding unit, the substrate according to claim 7 It is a processing device.
According to this configuration, since the water droplets that have landed on the phosphoric acid aqueous solution on the substrate solidify and move in the phosphoric acid aqueous solution toward the upper surface of the substrate, they are less likely to diffuse in the phosphoric acid aqueous solution. Therefore, the amount of water that reaches the interface between the substrate and the phosphoric acid aqueous solution increases, and the pyrophosphoric acid that exists at the interface between the substrate and the phosphoric acid aqueous solution decreases. As a result, a decrease in the etching selectivity is suppressed or prevented.

The invention according to claim 9 is any one of claims 1 to 8 , wherein the heating means is means for heating the substrate before the phosphoric acid supply means supplies the phosphoric acid aqueous solution to the upper surface of the substrate. The substrate processing apparatus according to one item.

According to this configuration, the heating unit starts heating the substrate before the phosphoric acid supply unit supplies the phosphoric acid aqueous solution to the upper surface of the substrate. Therefore, the phosphoric acid aqueous solution is supplied to the upper surface of the heated substrate. Therefore, the time for the heating means to raise the temperature of the phosphoric acid aqueous solution to a predetermined temperature can be shortened. Thereby, etching time can be shortened.
According to a tenth aspect of the present invention, the heating means includes an infrared heater that irradiates the substrate with infrared rays, and the infrared ray is in a state where at least a part of the infrared heater is in contact with the liquid film of the phosphoric acid aqueous solution. emit infrared from the heater, a substrate processing apparatus according to any one of claims 1-9.

  According to this structure, the infrared rays emitted from the infrared heater are irradiated onto the substrate, and the radiant heat is transmitted from the infrared heater to the substrate. Thereby, the substrate is heated. Therefore, the phosphoric acid aqueous solution on the substrate is heated. Alternatively, the phosphoric acid aqueous solution on the substrate is directly heated by the infrared rays. The infrared heater emits infrared rays in a state where at least a part of the infrared heater is in contact with the liquid film of the phosphoric acid aqueous solution. Therefore, evaporation of water from the phosphoric acid aqueous solution is suppressed by the infrared heater. Thereby, the concentration change of the phosphoric acid aqueous solution can be suppressed and the etching rate can be stabilized. Furthermore, generation of pyrophosphoric acid in the phosphoric acid aqueous solution can be suppressed, and a decrease in etching selectivity can be prevented.

The invention according to claim 11 is the heating apparatus according to any one of claims 1 to 10 , wherein the heating means heats the liquid film of the phosphoric acid aqueous solution to the boiling point of the phosphoric acid aqueous solution by heating the substrate. It is a substrate processing apparatus of description.
According to this configuration, the phosphoric acid aqueous solution on the substrate is heated to the boiling point by the heating means. Thereby, an etching rate can be raised. Moreover, although the amount of water evaporation from the phosphoric acid aqueous solution increases when the phosphoric acid aqueous solution is heated to the boiling point, the water supply means replenishes the phosphoric acid aqueous solution on the substrate with water, so the concentration change of the phosphoric acid aqueous solution Can be suppressed. Furthermore, pyrophosphoric acid in the phosphoric acid aqueous solution can be reduced by replenishing water. Thereby, the fall of an etching selectivity can be suppressed, suppressing the fluctuation | variation of an etching rate.

The invention according to claim 12 is the substrate processing apparatus according to claim 11 , wherein the heating means raises the temperature of the substrate to a temperature equal to or higher than the boiling point of the phosphoric acid aqueous solution.
According to this configuration, the substrate is heated to a temperature not lower than the boiling point of the phosphoric acid aqueous solution. Therefore, the temperature of the upper surface of the substrate in contact with the phosphoric acid aqueous solution rises to a temperature equal to or higher than the boiling point of the phosphoric acid aqueous solution. Therefore, the phosphoric acid aqueous solution can be maintained in a boiling state at the interface between the substrate and the phosphoric acid aqueous solution. Thereby, an etching rate can be raised.

The invention according to claim 13, further comprising a chamber for accommodating a substrate holding means, and a humidifying means for supplying a high humidity of the humidified gas than the humidity of the chamber into the chamber, according to claim 1 to 12 It is a substrate processing apparatus as described in any one of these.
According to this configuration, a humidified gas having a higher humidity than the humidity in the chamber is supplied into the chamber. Thereby, the humidity in the chamber increases, and the water vapor pressure in the chamber rises to a value below the saturated water vapor pressure. Therefore, evaporation of water from the phosphoric acid aqueous solution on the substrate is suppressed. Therefore, pyrophosphoric acid in the phosphoric acid aqueous solution can be reduced. Thereby, the fall of an etching selectivity can be suppressed.

The invention described in claim 14 is the substrate processing apparatus according to claim 13 , wherein the humidifying means supplies the humidified gas having a temperature higher than the atmospheric temperature in the chamber into the chamber.
According to this configuration, a humidified gas having a humidity higher than the humidity in the chamber and higher than the atmospheric temperature in the chamber is supplied into the chamber. Thereby, the humidity in the chamber increases and the temperature in the chamber increases. Therefore, the evaporation of water from the phosphoric acid aqueous solution on the substrate can be further suppressed, and the temperature drop of the phosphoric acid aqueous solution on the substrate can be suppressed. Therefore, it is possible to suppress a decrease in the etching rate and the etching selectivity.

According to a fifteenth aspect of the present invention, the humidifying means includes an annular discharge port that discharges the humidified gas radially in a direction parallel to the upper surface of the substrate, and the annular discharge port is above the liquid film of the phosphoric acid aqueous solution. by discharging the humidifying gas to the outlet, to form a stream of the humidified gas radiating from the annular discharge opening above the liquid film of the aqueous solution of phosphoric acid, in the substrate processing apparatus according to claim 13 or 14 is there.

  According to this configuration, the humidified gas is discharged radially from the annular discharge port in a direction parallel to the upper surface of the substrate. As a result, a humidified gas stream that radiates from the annular discharge port is formed above the phosphoric acid aqueous solution liquid film, and the phosphoric acid aqueous solution liquid film is covered with the humidified gas stream. Therefore, the humidity above the liquid film of the phosphoric acid aqueous solution is reliably increased. Thereby, evaporation of water from the phosphoric acid aqueous solution on the substrate is suppressed. Therefore, pyrophosphoric acid in the phosphoric acid aqueous solution can be reduced, and a decrease in etching selectivity can be suppressed.

In the invention described in claim 16 , the heating means includes an infrared heater that irradiates the upper surface of the substrate with infrared rays, and a fluid nozzle that supplies a heating fluid having a temperature higher than that of the substrate to the entire lower surface of the substrate. It is a substrate processing apparatus as described in any one of Claims 1-15 . The heating fluid may be a liquid (heating liquid) or a gas (heating gas). When the heating fluid is a gas, a humidified gas having a temperature higher than that of the substrate may be used as the heating fluid.

  According to this structure, the infrared rays emitted from the infrared heater are applied to the upper surface of the substrate, and the substrate is heated. Furthermore, the heating fluid discharged from the fluid nozzle is supplied to the entire lower surface of the substrate, and the entire region of the substrate is heated. Thus, since the heating fluid having a temperature higher than that of the substrate is supplied to the entire lower surface of the substrate, the uniformity of the temperature of the substrate can be improved. Therefore, the uniformity of the temperature of the liquid film of the phosphoric acid aqueous solution can be improved. Therefore, the uniformity of etching can be improved.

The invention according to claim 17 is the substrate processing apparatus according to claim 16 , wherein the fluid nozzle discharges superheated steam toward the lower surface of the substrate.
According to this configuration, superheated steam at 100 ° C. or higher as a heating fluid is discharged from the heating nozzle and supplied to the entire lower surface of the substrate. Thereby, the substrate is heated uniformly, and the liquid film of the phosphoric acid aqueous solution is heated uniformly. Furthermore, since the superheated steam is supplied to the substrate, the humidity around the substrate is increased. Therefore, evaporation of water from the phosphoric acid aqueous solution on the substrate is suppressed. Therefore, pyrophosphoric acid in the phosphoric acid aqueous solution can be reduced, and a decrease in etching selectivity can be suppressed.

It is the schematic diagram which looked at the inside of the processing unit with which the substrate processing apparatus concerning a 1st embodiment of the present invention was equipped horizontally. It is the schematic diagram which looked at the spin chuck, the infrared heater, and the pure water nozzle horizontally. It is a typical top view which shows a spin chuck, an infrared heater, and a pure water nozzle. It is process drawing for demonstrating an example of the process of the board | substrate performed by the process unit. It is a schematic diagram which shows a board | substrate when the phosphoric acid supply process is performed. It is a schematic diagram which shows a board | substrate when the paddle process is performed. It is a schematic diagram which shows a board | substrate when the paddle process, a heating process, and a pure water supply process are performed. It is a graph which shows an example of the relationship of the distance to the radial direction from the center of a board | substrate to the pure water landing position, the moving speed of a liquid landing position, and the supply amount of pure water. It is a graph which shows the other example of the relationship between the distance to the radial direction from the center of a board | substrate to the pure water landing position, the moving speed of a liquid landing position, and the supply amount of pure water. It is a graph which shows the relationship between the temperature of the phosphoric acid aqueous solution supplied to a board | substrate, an etching rate, and an etching selectivity. It is the schematic diagram which looked horizontally at the infrared heater and spin chuck which concern on 2nd Embodiment of this invention. It is a longitudinal cross-sectional view of the infrared heater which concerns on 2nd Embodiment of this invention. It is the schematic diagram which looked at the heating nozzle and spin chuck which concern on 3rd Embodiment of this invention horizontally. It is a schematic diagram which shows the longitudinal cross-section and bottom face of the infrared heater and pure water nozzle which concern on 4th Embodiment of this invention. It is a schematic diagram of the pure water supply apparatus which concerns on 5th Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a schematic view of the inside of a processing unit 2 provided in the substrate processing apparatus 1 according to the first embodiment of the present invention viewed horizontally. FIG. 2 is a schematic view of the spin chuck 5, the infrared heater 31, and the pure water nozzle 38 viewed horizontally. FIG. 3 is a schematic plan view showing the spin chuck 5, the infrared heater 31, and the pure water nozzle 38.

  The substrate processing apparatus 1 is a single-wafer type apparatus that processes a disk-shaped substrate W such as a semiconductor wafer one by one. The substrate processing apparatus 1 includes a plurality of processing units 2 (only one processing unit 2 is shown in FIG. 1) that processes the substrate W using a processing fluid such as a processing liquid or a processing gas, and the substrate processing apparatus 1. And a control device 3 for controlling the operation of the device and the opening / closing of the valve. Note that the substrate processing apparatus 1 may have a single processing unit 2.

  The processing unit 2 includes a box-shaped chamber 4 having an internal space, a spin chuck 5 that holds the substrate W horizontally in the chamber 4 and rotates the substrate W about a vertical rotation axis A1 passing through the center of the substrate W. A processing liquid supply device (phosphoric acid supply device 6, SC1 supply device 7, rinse liquid supply device 8, pure water supply device 36) that supplies the processing liquid to the substrate W, and a cylindrical cup 9 that surrounds the spin chuck 5. And a heating device 10 for heating the substrate W.

  As shown in FIG. 1, the chamber 4 is a box-shaped partition 11 that houses the spin chuck 5 and the like, and a blower unit that sends clean air (air filtered by a filter) from the top of the partition 11 into the partition 11. An FFU 12 (fan filter unit 12) and an exhaust duct 13 that exhausts gas in the chamber 4 from the lower part of the partition wall 11 are included. The FFU 12 is disposed above the partition wall 11. The FFU 12 sends clean air downward from the ceiling of the partition wall 11 into the chamber 4. The exhaust duct 13 is connected to the bottom of the cup 9 and guides the gas in the chamber 4 toward an exhaust facility provided in a factory where the substrate processing apparatus 1 is installed. Therefore, a downflow (downflow) that flows downward from above in the chamber 4 is formed by the FFU 12 and the exhaust duct 13. The processing of the substrate W is performed in a state where a down flow is formed in the chamber 4.

  As shown in FIG. 1, the spin chuck 5 includes a disk-shaped spin base 14 held in a horizontal posture, a plurality of chuck pins 15 that hold the substrate W in a horizontal posture above the spin base 14, and A rotation shaft 16 extending downward from the central portion of the spin base 14 and a spin motor 17 as a substrate rotation means for rotating the substrate W and the spin base 14 around the rotation axis A1 by rotating the rotation shaft 16 are included. The spin chuck 5 is not limited to a clamping chuck in which a plurality of chuck pins 15 are brought into contact with the peripheral end surface of the substrate W, and the back surface (lower surface) of the substrate W, which is a non-device forming surface, is adsorbed to the upper surface of the spin base 14. Thus, a vacuum chuck that holds the substrate W horizontally may be used.

  As shown in FIG. 1, the cup 9 is disposed outward (in a direction away from the rotation axis A <b> 1) from the substrate W held by the spin chuck 5. The cup 9 surrounds the spin base 14. When the processing liquid is supplied to the substrate W while the spin chuck 5 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 9 a of the cup 9 that opens upward is disposed above the spin base 14. Therefore, the treatment liquid such as the chemical liquid or the rinse liquid discharged around the substrate W is received by the cup 9. Then, the processing liquid received by the cup 9 is sent to a collection device or a waste liquid device (not shown).

  As shown in FIG. 1, the phosphoric acid supply device 6 supplies a phosphoric acid nozzle 18 that discharges a phosphoric acid aqueous solution toward the substrate W held by the spin chuck 5, and supplies the phosphoric acid aqueous solution to the phosphoric acid nozzle 18. The temperature of the phosphoric acid pipe 19, the phosphoric acid valve 20 for switching the supply and stoppage of the phosphoric acid aqueous solution from the phosphoric acid pipe 19 to the phosphoric acid nozzle 18, and the temperature of the phosphoric acid aqueous solution supplied to the phosphoric acid nozzle 18 are set to room temperature (20 And a phosphoric acid temperature adjusting device 21 that raises the temperature to a temperature higher than a predetermined temperature within a range of from 30 ° C to 30 ° C.

  When the phosphoric acid valve 20 is opened, the phosphoric acid aqueous solution whose temperature is adjusted by the phosphoric acid temperature adjusting device 21 is supplied from the phosphoric acid pipe 19 to the phosphoric acid nozzle 18 and discharged from the phosphoric acid nozzle 18. The phosphoric acid temperature adjusting device 21 maintains the temperature of the phosphoric acid aqueous solution at a constant temperature within a range of 80 to 215 ° C., for example. The temperature of the phosphoric acid aqueous solution adjusted by the phosphoric acid temperature adjusting device 21 may be a boiling point at the concentration or a temperature lower than the boiling point. The phosphoric acid aqueous solution is an aqueous solution containing phosphoric acid as a main component, and the concentration thereof is, for example, in the range of 50% to 100%, preferably around 80%.

  As shown in FIG. 1, the phosphoric acid supply device 6 further includes a nozzle arm 22 having a phosphoric acid nozzle 18 attached to the tip, and a nozzle arm around a rotation axis A <b> 2 extending in the vertical direction around the spin chuck 5. And a phosphate nozzle moving device 23 that moves the phosphate nozzle 18 horizontally and vertically by rotating the nozzle arm 22 in the vertical direction along the rotation axis A2. The phosphoric acid nozzle moving device 23 includes a processing position where the phosphoric acid aqueous solution discharged from the phosphoric acid nozzle 18 is supplied to the upper surface of the substrate W, and a retreat position where the phosphoric acid nozzle 18 is retreated around the substrate W in plan view. In between, the phosphoric acid nozzle 18 is moved horizontally.

As shown in FIG. 1, the SC1 supply device 7 includes an SC1 nozzle 24 that discharges SC1 (mixed liquid containing NH ₄ OH and H ₂ O ₂ ) toward the substrate W held by the spin chuck 5. An SC1 pipe 25 for supplying SC1 to the SC1 nozzle 24, an SC1 valve 26 for switching supply and stop of supply of SC1 from the SC1 pipe 25 to the SC1 nozzle 24, and an SC1 nozzle moving device 27 for moving the SC1 nozzle 24 horizontally and vertically. Including. When the SC1 valve 26 is opened, SC1 supplied from the SC1 pipe 25 to the SC1 nozzle 24 is discharged from the SC1 nozzle 24. The SC1 nozzle moving device 27 is configured such that the SC1 between the processing position where SC1 discharged from the SC1 nozzle 24 is supplied to the upper surface of the substrate W and the retreat position where the SC1 nozzle 24 retreats around the substrate W in plan view. The nozzle 24 is moved horizontally.

  As shown in FIG. 1, the rinsing liquid supply device 8 includes a rinsing liquid nozzle 28 that discharges the rinsing liquid toward the substrate W held by the spin chuck 5, and a rinsing liquid that supplies the rinsing liquid to the rinsing liquid nozzle 28. A pipe 29 and a rinse liquid valve 30 for switching supply and stop of the supply of the rinse liquid from the rinse liquid pipe 29 to the rinse liquid nozzle 28 are included. The rinse liquid nozzle 28 is a fixed nozzle that discharges the rinse liquid in a state where the discharge port of the rinse liquid nozzle 28 is stationary. The rinsing liquid supply device 8 may include a rinsing liquid nozzle moving device that moves the rinsing liquid landing position relative to the upper surface of the substrate W by moving the rinsing liquid nozzle 28.

  When the rinse liquid valve 30 is opened, the rinse liquid supplied from the rinse liquid pipe 29 to the rinse liquid nozzle 28 is discharged from the rinse liquid nozzle 28 toward the center of the upper surface of the substrate W. The rinse liquid is, for example, pure water (deionized water). The rinse liquid is not limited to pure water, but may be any of carbonated water, electrolytic ion water, hydrogen water, ozone water, IPA (isopropyl alcohol), and hydrochloric acid water having a diluted concentration (for example, about 10 to 100 ppm). Good.

As shown in FIG. 1, the heating device 10 includes a radiation heating device that heats the substrate W by radiation. The radiant heating device includes an infrared heater 31 that irradiates the substrate W with infrared rays, a heater arm 32 with the infrared heater 31 attached to the tip, and a heater moving device 33 that moves the heater arm 32.
As shown in FIG. 2, the infrared heater 31 includes an infrared lamp 34 that emits infrared rays, and a lamp housing 35 that houses the infrared lamp 34. The infrared lamp 34 is disposed in the lamp housing 35. As shown in FIG. 3, the lamp housing 35 is smaller than the substrate W in plan view. Therefore, the infrared heater 31 disposed in the lamp housing 435 is smaller than the substrate W in plan view. The infrared lamp 34 and the lamp housing 35 are attached to the heater arm 32. Accordingly, the infrared lamp 34 and the lamp housing 35 move together with the heater arm 32.

The infrared lamp 34 includes a filament and a quartz tube that accommodates the filament. The infrared lamp 34 (for example, a halogen lamp) in the heating device 10 may be a carbon heater or a heating element other than these. At least a part of the lamp housing 35 is formed of a material having optical transparency and heat resistance such as quartz.
When the infrared lamp 34 emits light, the infrared lamp 34 emits light including infrared rays. The light containing infrared rays passes through the lamp housing 35 and is emitted from the outer surface of the lamp housing 35, or the lamp housing 35 is heated to emit radiant light from the outer surface. The liquid film of the phosphoric acid aqueous solution held on the substrate W and its upper surface is heated by transmitted light and radiated light from the outer surface of the lamp housing 35. As described above, light including infrared rays is radiated from the outer surface of the lamp housing 35 by transmission or radiation. Hereinafter, the infrared lamp 34 will be described by focusing on the infrared rays transmitted through the outer surface of the lamp housing 35. .

  As shown in FIG. 2, the lamp housing 35 has a bottom wall parallel to the upper surface of the substrate W. The infrared lamp 34 is disposed above the bottom wall. The lower surface of the bottom wall includes a flat substrate facing surface that is parallel to the upper surface of the substrate W and is flat. In a state where the infrared heater 31 is disposed above the substrate W, the substrate facing surface of the lamp housing 35 faces the upper surface of the substrate W in the vertical direction with a space therebetween. In this state, when the infrared lamp 34 emits infrared rays, the infrared rays are irradiated on the upper surface of the substrate W through the substrate facing surface of the lamp housing 35. The substrate facing surface is, for example, a circle whose diameter is smaller than the radius of the substrate W. The substrate facing surface is not limited to a circular shape, and may be a rectangular shape whose length in the longitudinal direction is equal to or larger than the radius of the substrate W, or may be a shape other than a circular shape and a rectangular shape.

  As shown in FIG. 1, the heater moving device 33 holds the infrared heater 31 at a predetermined height. The heater moving device 33 moves the infrared heater 31 vertically. Further, the heater moving device 33 moves the infrared heater 31 horizontally by rotating the heater arm 32 around the rotation axis A <b> 3 extending in the vertical direction around the spin chuck 5. As a result, a heating region (a partial region in the upper surface of the substrate W) that is irradiated with light such as infrared rays and heated moves within the upper surface of the substrate W. As shown in FIG. 2, the heater moving device 33 horizontally moves the tip of the heater arm 32 along an arcuate locus X1 passing through the center of the substrate W in plan view. Accordingly, the infrared heater 31 moves in a horizontal plane including the upper side of the spin chuck 5.

  Infrared rays from the infrared heater 31 are applied to a heating region in the upper surface of the substrate W. The control device 3 rotates the infrared heater 31 around the rotation axis A3 by the heater moving device 33 while rotating the substrate W by the spin chuck 5 while the infrared heater 31 emits light. Thereby, the upper surface of the substrate W is scanned by the heating region of the infrared heater 31. Therefore, light such as infrared light is absorbed by at least one of the upper surface of the substrate W and the liquid film of the processing liquid held on the upper surface of the substrate W, and radiant heat is transmitted from the infrared lamp 34 to the substrate W. Therefore, when the infrared lamp 34 emits light while a liquid such as a processing liquid is held on the substrate W, the temperature of the substrate W increases, and accordingly, the temperature of the liquid on the substrate W also increases. Alternatively, the liquid itself on the substrate W is heated to raise the temperature.

  As shown in FIG. 1, the processing unit 2 includes a pure water supply device 36 that discharges pure water toward the substrate W. The pure water supply device 36 includes a pure water nozzle 38 that discharges pure water from the pure water discharge port 37 toward the substrate W, a pure water pipe 39 that supplies pure water to the pure water nozzle 38, and a pure water pipe 39. A pure water valve 40 that switches between supply and stop of pure water to the pure water nozzle 38 and a pure water flow rate adjustment valve 41 that adjusts the flow rate of pure water supplied from the pure water pipe 39 to the pure water nozzle 38 are included. .

  The pure water nozzle 38 includes a single pure water discharge port 37 that discharges pure water intermittently, and preferably discharges pure water droplets one by one. The pure water nozzle 38 may include a plurality of pure water discharge ports 37. Pure water is dropped vertically downward from a pure water discharge port 37 as a droplet discharge port. Therefore, in a state where the pure water discharge port 37 is opposed to the upper surface of the substrate W in the vertical direction, the pure water droplets drop vertically downward toward the upper surface of the substrate W. The droplet discharge and discharge stop are switched by the pure water valve 40, and the particle size of the droplet is adjusted by the opening of the pure water flow rate adjustment valve 41.

  As shown in FIG. 1, the pure water nozzle 38 is attached to the heater arm 32. Therefore, the pure water nozzle 38 moves in the horizontal direction and the vertical direction together with the infrared heater 31. The infrared heater 31 is attached to the heater arm 32 on the root side of the heater arm 32 with respect to the pure water nozzle 38. Thereby, the horizontal distance from the rotation axis A3 to the pure water nozzle 38 is longer than the horizontal distance from the rotation axis A3 to the infrared heater 31.

  As shown in FIG. 3, when the heater arm 32 is rotated by the heater moving means 33, pure water from the pure water nozzle 38 is deposited on the upper surface of the substrate W along an arcuate locus X <b> 1 passing through the center of the substrate W. To do. On the other hand, the infrared heater 31 moves on the upper surface of the substrate W with a rotation radius smaller than the locus X1. The heater moving means 33 moves not only the infrared heater 31 but also the pure water nozzle 38 along the upper surface of the substrate W. For this reason, the heater moving means 33 also functions as a pure water supply position moving means.

As shown in FIG. 3, the control device 3 rotates the substrate W in the constant rotation direction Dr by the spin chuck 5.
When performing a heating process and a pure water supply process (step S4 in FIG. 4), which will be described later, the control device 3 indicates that the landing position of pure water discharged from the pure water nozzle 38 is indicated by an arrow in FIG. The heater arm 32 is reciprocally rotated between the center portion of the upper surface of the substrate W (position shown in FIG. 3) and the peripheral portion of the upper surface of the substrate W so as to reciprocate inside. As a result, the pure water discharged from the pure water nozzle 38 comes into contact with the phosphoric acid aqueous solution region upstream of the infrared irradiation region of the infrared heater 31 with respect to the rotation direction Dr of the substrate W.

  The pure water droplets dropped on the upper surface of the rotating substrate W move in the rotation direction Dr of the substrate W. That is, the pure water droplet moves to the downstream side in the rotation direction Dr of the substrate W. The infrared heater 31 is heated by irradiating light such as infrared rays to the downstream area of the pure water landing position. Accordingly, when the substrate W is rotating and the infrared heater 31 emits light such as infrared rays, a drop of pure water falls on a part of the upper surface of the substrate W. It moves to the heating area and is heated. Therefore, even if a droplet having a temperature lower than that of the substrate W is supplied to the substrate W, the temperature of the substrate W is brought close to the original temperature (the temperature before the droplet is supplied).

FIG. 4 is a process diagram for explaining an example of the processing of the substrate W performed by the processing unit 2. 5A, 5B, and 5C are schematic views showing the substrate W being processed. In the following, reference is made to FIG. Reference is appropriately made to FIGS. 4, 5A, 5B, and 5C.
Below, a thin film of LP-SiN (Low Pressure-Silicon Nitride), which is an example of a silicon nitride film, and a thin film of LP-TEOS (Low Pressure-Tetraethyl orthosilicate), which is an example of a silicon oxide film, are formed on the surface layer. The selective etching for supplying a phosphoric acid aqueous solution to the surface of the substrate W (silicon wafer) and selectively etching the LP-SiN thin film will be described. The silicon oxide film is not limited to a TEOS thin film, and may be a thermal oxide film or a silicate glass-based oxide film.

  When the substrate W is processed by the processing unit 2, a carry-in process (step S1 in FIG. 4) for carrying the substrate W into the chamber 4 is performed. Specifically, the control device 3 causes the hand of the transfer robot (not shown) holding the substrate W to enter the chamber 4 with all the nozzles retracted from above the spin chuck 5. . Then, the control device 3 causes the transfer robot to place the substrate W on the spin chuck 5. Thereafter, the control device 3 holds the substrate W on the spin chuck 5. Subsequently, the control device 3 starts rotating the substrate W at a low speed (for example, 1 to 30 rpm) by the spin chuck 5. After the substrate W is placed on the spin chuck 5, the control device 3 retracts the hand of the transfer robot from the chamber 4.

  Next, a phosphoric acid supply process (step S2 in FIG. 4) is performed as an etching process for supplying a phosphoric acid aqueous solution, which is an example of an etching liquid, to the substrate W. Specifically, the control device 3 controls the phosphoric acid nozzle moving device 23 to move the phosphoric acid nozzle 18 from the retracted position to the processing position. Accordingly, the phosphoric acid nozzle 18 is disposed on the rotation axis A1 of the substrate W above the substrate W. Thereafter, the control device 3 opens the phosphoric acid valve 20 and discharges the phosphoric acid aqueous solution whose temperature is adjusted by the phosphoric acid temperature adjusting device 21 from the phosphoric acid nozzle 18 toward the upper surface of the rotating substrate W. In this state, the control device 3 controls the phosphoric acid nozzle moving device 23 to move the landing position of the phosphoric acid aqueous solution on the upper surface of the substrate W between the central portion and the peripheral portion.

  As shown in FIG. 5A, the phosphoric acid aqueous solution discharged from the phosphoric acid nozzle 18 lands on the upper surface of the substrate W, and then flows outward along the upper surface of the substrate W by centrifugal force. Therefore, the phosphoric acid aqueous solution is supplied to the entire upper surface of the substrate W, and a liquid film of the phosphoric acid aqueous solution covering the entire upper surface of the substrate W is formed on the substrate W. Thereby, the upper surface of the substrate W is etched, and the silicon nitride film is selectively removed. Further, since the controller 3 moves the landing position of the phosphoric acid aqueous solution with respect to the upper surface of the substrate W between the central portion and the peripheral portion while the substrate W is rotating, the landing position of the phosphoric acid aqueous solution is Passes through the entire upper surface of the substrate W, and the entire upper surface of the substrate W is scanned. Therefore, the phosphoric acid aqueous solution discharged from the phosphoric acid nozzle 18 is directly supplied to the entire upper surface of the substrate W, and the entire upper surface of the substrate W is processed uniformly.

  Next, a paddle process (step S3 in FIG. 4) for holding the liquid film of the phosphoric acid aqueous solution on the substrate W in a state where the supply of the phosphoric acid aqueous solution to the substrate W is stopped is performed. Specifically, the control device 3 controls the spin chuck 5 to stop the substrate W or supply the phosphoric acid while the entire upper surface of the substrate W is covered with the liquid film of the phosphoric acid aqueous solution. The rotational speed of the substrate W is reduced to a low rotational speed (for example, less than 10 rpm) slower than the rotational speed of the substrate W in the process. Therefore, the centrifugal force acting on the phosphoric acid aqueous solution on the substrate W is weakened, and the amount of the phosphoric acid aqueous solution discharged from the substrate W is reduced. The controller 3 closes the phosphoric acid valve 20 and stops the discharge of the phosphoric acid aqueous solution from the phosphoric acid nozzle 18 while the substrate W is stationary or the substrate W is rotating at a low rotational speed. . As a result, as shown in FIG. 5B, the paddle-like liquid film of the phosphoric acid aqueous solution covering the entire upper surface of the substrate W is held on the substrate W while the supply of the phosphoric acid aqueous solution to the substrate W is stopped. . After stopping the supply of the phosphoric acid aqueous solution to the substrate W, the control device 3 controls the phosphoric acid nozzle moving device 23 to retract the phosphoric acid nozzle 18 from above the spin chuck 5.

  Next, a heating process for heating the phosphoric acid aqueous solution on the substrate W (step S4 in FIG. 4), and a pure water supply process for supplying pure water droplets to the phosphoric acid aqueous solution on the substrate W (step S4 in FIG. 4). ) Is performed in parallel with the paddle process. Specifically, the control device 3 starts light emission from the infrared heater 31. Thereafter, the control device 3 causes the heater moving device 33 to move the infrared heater 31 and the pure water nozzle 38 from the retracted position to the processing position. After the infrared heater 31 and the pure water nozzle 38 are disposed above the substrate W, the control device 3 is configured so that the infrared irradiation area on the upper surface of the substrate W is in the region indicated by the arrow in FIG. The infrared heater 31 and the deionized water nozzle 38 are moved horizontally by the heater moving device 33 so as to reciprocate between them. At this time, the control device 3 may move the infrared heater 31 in a state where the substrate facing surface of the infrared heater 31 is in contact with the liquid film of the phosphoric acid aqueous solution on the substrate W. The infrared heater 31 may be moved while being separated from the liquid film of the phosphoric acid aqueous solution on the substrate W by a predetermined distance.

  The control device 3 opens and closes the pure water valve 40 a plurality of times while the infrared irradiation position reciprocates between the central portion of the upper surface of the substrate W and the peripheral portion of the upper surface of the substrate W. As a result, as shown in FIG. 5C, the pure water landing position moves between the central portion of the upper surface of the substrate W and the peripheral portion of the upper surface of the substrate W, and a plurality of pure water droplets are added to the pure water nozzle 38. Are discharged from the pure water discharge port 37 one by one. Accordingly, a plurality of pure water droplets are supplied to a plurality of positions in the upper surface of the substrate W in a state where the discharge of the phosphoric acid aqueous solution from the substrate W is stopped. After the heating of the substrate W by the infrared heater 31 is performed for a predetermined time, the control device 3 stops the discharge of the liquid droplets from the pure water nozzle 38 and moves the infrared heater 31 and the pure water nozzle 38 above the substrate W. Evacuate from. Thereafter, the control device 3 stops the light emission of the infrared heater 31.

  Thus, since the control device 3 reciprocates the infrared irradiation position with respect to the upper surface of the substrate W between the central portion and the peripheral portion while the substrate W is rotating, the substrate W is heated uniformly. The Therefore, the phosphoric acid aqueous solution film covering the entire upper surface of the substrate W is also heated uniformly. The heating temperature of the substrate W by the infrared heater 31 is set to a temperature equal to or higher than the boiling point of the phosphoric acid aqueous solution at its concentration (100 ° C. or higher, for example, a predetermined temperature within 140 ° C. to 160 ° C.). Therefore, the phosphoric acid aqueous solution on the substrate W is heated to the boiling point at that concentration and maintained in a boiling state. In particular, when the heating temperature of the substrate W by the infrared heater 31 is set to be higher than the boiling point at the concentration of the phosphoric acid aqueous solution, the temperature at the interface between the substrate W and the phosphoric acid aqueous solution is higher than the boiling point. The etching of the substrate W is promoted.

In the heating step (S4), since the aqueous phosphoric acid solution is maintained in a boiling state, a large amount of water evaporates from the aqueous phosphoric acid solution. Accompanying the evaporation, pyrophosphoric acid (H ₄ P ₂ O ₇ ) for etching the silicon oxide film is generated by the reaction of 2H ₃ PO ₄ → H ₄ P ₂ O ₇ + H ₂ O. However, since the control device 3 supplies pure water in an amount corresponding to the evaporation amount of water from the phosphoric acid aqueous solution to the phosphoric acid aqueous solution on the substrate W, the water evaporated from the phosphoric acid aqueous solution is supplemented, and the phosphoric acid aqueous solution is supplied. Concentration change is reduced. Thereby, the fluctuation | variation of an etching rate is suppressed. Furthermore, since pyrophosphoric acid once generated in the phosphoric acid aqueous solution is reduced by the reaction with the replenished pure water, a decrease in etching selectivity is suppressed or prevented.

  Etching of the silicon oxide film is efficiently suppressed by reducing pyrophosphoric acid present at the interface between the substrate W and the phosphoric acid aqueous solution. In the pure water supply step, pure water is supplied to the phosphoric acid aqueous solution on the substrate W in the form of droplets. Since the supplied pure water droplets move in the phosphoric acid aqueous solution while solidified (see FIG. 5C), the pure water reliably reaches the interface between the substrate W and the phosphoric acid aqueous solution. It is possible to reliably reduce pyrophosphoric acid present at the interface. This reliably suppresses or prevents a decrease in the etching selection ratio.

  The pure water replenished with the phosphoric acid aqueous solution may be sprayed from the pure water discharge port 37. However, since most of the mist-like pure water is absorbed by the surface layer of the phosphoric acid aqueous solution, a sufficient amount of pure water may not reach the interface between the substrate W and the phosphoric acid aqueous solution. For this reason, the pure water discharged from the pure water discharge port 37 is preferably in the form of droplets. In addition, since the phosphoric acid aqueous solution on the substrate W is heated to 100 ° C. or higher, it is difficult to reach the surface layer of the phosphoric acid aqueous solution in the first place with atomized pure water that easily evaporates. Also from this viewpoint, it is desirable that the pure water discharged from the pure water discharge port 37 is in the form of droplets.

  The pure water replenished with the phosphoric acid aqueous solution may be discharged continuously from the pure water discharge port 37 or may be discharged intermittently from the pure water discharge port 37. However, it is difficult to continuously supply a small amount of water with high accuracy. In contrast, when pure water is intermittently discharged, a small amount of water can be supplied with relatively high accuracy. For this reason, when pure water is intermittently discharged from the pure water discharge port 37, changes in the concentration and temperature of the phosphoric acid aqueous solution can be more reliably suppressed.

  5C, when the substrate heating and pure water supply in step S4 are performed in a state where the substrate facing surface of the infrared heater 31 is in contact with the liquid film of the phosphoric acid aqueous solution on the substrate W as shown in FIG. 5C. It is desirable to prevent the pure water from being sandwiched between the liquid film of the phosphoric acid aqueous solution and the substrate facing surface of the infrared heater 31. This is because pure water has a boiling point lower than that of the phosphoric acid aqueous solution, and therefore, if it is sandwiched as described above, it may be vaporized instantaneously by heating of the infrared heater 31.

  Next, a phosphoric acid discharging process (step S5 in FIG. 4) for discharging the phosphoric acid aqueous solution on the substrate W is performed. Specifically, the control device 3 controls the spin chuck 5 so that the rotation speed (for example, higher than the rotation speed of the substrate W in the paddle process in the state where the supply of the liquid to the substrate W is stopped). The substrate W is rotated at 500 to 3000 rpm. As a result, a centrifugal force larger than that in the paddle process is applied to the phosphoric acid aqueous solution on the substrate W, and the phosphoric acid aqueous solution on the substrate W is shaken off around the substrate W. Further, the phosphoric acid aqueous solution scattered around the substrate W is received by the cup 9 and guided to the recovery device via the cup 9. Then, the phosphoric acid aqueous solution guided to the recovery device is supplied to the substrate W again. Thereby, the usage-amount of phosphoric acid aqueous solution is reduced.

  Next, the 1st rinse liquid supply process (step S6 of FIG. 4) which supplies the pure water which is an example of the rinse liquid to the board | substrate W is performed. Specifically, the control device 3 opens the rinse liquid valve 30 and discharges pure water from the rinse liquid nozzle 28 toward the center of the upper surface of the substrate W while rotating the substrate W. As a result, a pure water liquid film covering the entire upper surface of the substrate W is formed, and the phosphoric acid aqueous solution remaining on the substrate W is washed away with pure water. When a predetermined time has elapsed since the rinse liquid valve 30 was opened, the control device 3 closes the rinse liquid valve 30 and stops the discharge of pure water.

  Next, a chemical solution supply step (step S7 in FIG. 4) for supplying SC1 as an example of the chemical solution to the substrate W is performed. Specifically, the control device 3 controls the SC1 nozzle moving device 27 to move the SC1 nozzle 24 from the retracted position to the processing position. After the SC1 nozzle 24 is disposed above the substrate W, the control device 3 opens the SC1 valve 26 and discharges SC1 from the SC1 nozzle 24 toward the upper surface of the rotating substrate W. In this state, the controller 3 controls the SC1 nozzle moving device 27 to reciprocate the SC1 liquid landing position with respect to the upper surface of the substrate W between the central portion and the peripheral portion. When a predetermined time elapses after the SC1 valve 26 is opened, the control device 3 closes the SC1 valve 26 and stops the discharge of SC1. Thereafter, the control device 3 controls the SC1 nozzle moving device 27 to retract the SC1 nozzle 24 from above the substrate W.

  The SC1 discharged from the SC1 nozzle 24 lands on the upper surface of the substrate W and then flows outward along the upper surface of the substrate W by centrifugal force. Therefore, the pure water on the substrate W is swept away by the SC 1 and discharged around the substrate W. As a result, the pure water liquid film on the substrate W is replaced with the SC1 liquid film covering the entire upper surface of the substrate W. Further, since the controller 3 moves the SC1 liquid landing position with respect to the upper surface of the substrate W between the central portion and the peripheral portion while the substrate W is rotating, the SC1 liquid landing position is the substrate W The entire upper surface of the substrate W is scanned. Therefore, SC1 discharged from the SC1 nozzle 24 is directly sprayed over the entire upper surface of the substrate W, and the entire upper surface of the substrate W is processed uniformly.

  Next, a second rinse liquid supply step (step S8 in FIG. 4) for supplying pure water, which is an example of a rinse liquid, to the substrate W is performed. Specifically, the control device 3 opens the rinse liquid valve 30 and discharges pure water from the rinse liquid nozzle 28 toward the center of the upper surface of the substrate W while rotating the substrate W. As a result, the SC1 on the substrate W is washed away by the pure water and discharged around the substrate W. Therefore, the liquid film of SC1 on the substrate W is replaced with a liquid film of pure water that covers the entire upper surface of the substrate W. When a predetermined time has elapsed since the rinse liquid valve 30 was opened, the control device 3 closes the rinse liquid valve 30 and stops the discharge of pure water.

  Next, a drying process (step S9 in FIG. 4) for drying the substrate W is performed. Specifically, the control device 3 accelerates the rotation of the substrate W by the spin chuck 5 and rotates the substrate W at a high rotation speed (for example, 500 to 3000 rpm) faster than the rotation speed up to the second rinse liquid supply process. Let 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 elapses after the high-speed rotation of the substrate W is started, the control device 3 stops the rotation of the substrate W by the spin chuck 5.

  Next, an unloading step (Step S10 in FIG. 4) for unloading the substrate W from the chamber 4 is performed. Specifically, the control device 3 releases the holding of the substrate W by the spin chuck 5. Thereafter, the control device 3 causes the hand of the transfer robot (not shown) to enter the chamber 4 with all the nozzles retracted from above the spin chuck 5. Then, the control device 3 holds the substrate W on the spin chuck 5 on the hand of the transfer robot. Thereafter, the control device 3 retracts the hand of the transfer robot from the chamber 4. Thereby, the processed substrate W is unloaded from the chamber 4.

FIG. 6 is a graph showing an example of the relationship between the radial distance from the center of the substrate W to the pure water landing position, the radial movement speed of the liquid landing position, and the pure water supply flow rate. FIG. 7 is a graph showing another example of the relationship between the radial distance from the center of the substrate W to the pure water landing position, the movement speed in the radial direction of the liquid landing position, and the pure water supply flow rate.
The control device 3 moves the pure water landing position with respect to the upper surface of the substrate W by moving the pure water nozzle 38 horizontally by the heater moving device 33. Further, the control device 3 controls the opening degree of the pure water flow rate adjustment valve 41 to change the particle size (volume) of the liquid droplets discharged from the pure water nozzle 38, and the pure water from the pure water discharge port 37. Control the water discharge flow rate.

  The etching amount of the silicon nitride film is desirably uniform over the entire upper surface of the substrate W. For this purpose, it is necessary to increase the in-plane uniformity of the etching rate. In other words, it is necessary to make the etching rate of the silicon nitride film substantially the same between the peripheral portion on the upper surface of the substrate W and the central portion of the upper surface. Since the etching rate of the silicon nitride film depends on the concentration of the phosphoric acid aqueous solution, it is necessary to replenish pure water so that the concentration is constant over the entire upper surface of the substrate W. When the substrate W is stopped or substantially stopped (rotating at several rpm), the pure water landing position moves on the upper surface of the substrate W in the radial direction of the substrate W. It is desirable that the speed (referred to as the substrate traverse speed; the same applies hereinafter) be constant and the discharge flow rate of pure water from the pure water discharge port 37 be constant. In this way, substantially the same amount of pure water is supplied per unit area to the upper surface periphery and the center of the upper surface of the substrate W, so that the concentration of the phosphoric acid aqueous solution can be made uniform over the upper surface of the substrate W. it can. Therefore, the in-plane uniformity of the etching rate can be increased.

  However, when the substrate W is rotated at a relatively high speed in the pure water supply step described above, a centrifugal force that causes concentration unevenness in the radial direction of the substrate W acts on the phosphoric acid aqueous solution on the substrate W. Since the aqueous phosphoric acid solution has a higher viscosity than water, it is considered that the aqueous phosphoric acid solution is less likely to move out of the substrate W than pure water. Accordingly, a large amount of pure water moves from the central portion of the upper surface of the substrate W to the peripheral portion of the upper surface of the substrate W, and the concentration of the phosphoric acid aqueous solution becomes relatively high at the central portion of the substrate W. It is considered that the concentration of the phosphoric acid aqueous solution becomes relatively low.

In fact, when the substrate traversing speed is constant and the discharge flow rate of pure water from the pure water discharge port 37 is constant, the inventors of the present application increase the rotation speed of the substrate W to about 10 rpm, for example. A phenomenon was confirmed in which the etching amount of the silicon nitride film at the peripheral edge of the upper surface of the substrate was smaller than the etching amount at the center of the upper surface of the substrate W.
This is presumably because the above-described mechanism acted on the liquid film on the substrate W. That is, when the rotation speed of the substrate W is about 10 rpm, the thickness of the liquid film on the substrate W is substantially uniform. This is considered to be because the concentration of the phosphoric acid aqueous solution at the peripheral edge of the substrate W was lowered as a result. Therefore, when the pure water is supplied to the liquid film of the phosphoric acid aqueous solution on the substrate W while rotating the substrate W at a relatively high speed (for example, 10 rpm or more), the center of the upper surface of the substrate W is more than the peripheral edge of the upper surface of the substrate W. If the supply amount of pure water per unit area is increased in the portion, the variation in the concentration of the phosphoric acid aqueous solution in the radial direction of the substrate W can be reduced, and as a result, the variation in the etching rate in the radial direction of the substrate W can be suppressed or It can be prevented.

  In order to increase the amount of pure water supplied per unit area at the center of the upper surface rather than the peripheral edge of the upper surface of the substrate W, at least one of the substrate traversing speed and the discharge flow rate of pure water from the pure water discharge port 37 is determined as pure water landing liquid. What is necessary is just to control according to a position. For example, the control device 3 controls the heater moving means 33 so that the substrate traversing speed is smaller at the center of the upper surface of the substrate W than at the peripheral edge of the upper surface of the substrate W. Alternatively, the pure water supply device 36 may be controlled so that the pure water discharge flow rate from the pure water discharge port 37 is larger at the center of the upper surface of the substrate W than at the peripheral edge of the upper surface of the substrate W (see FIG. 6).

  When the substrate W is rotated at a higher speed, it is necessary to further increase the amount of pure water supplied per unit area at the center of the upper surface of the substrate W. In this case, the control device 3 may control as shown in FIG. That is, the control device 3 controls the heater moving means 33 so that the substrate traverse speed decreases as the pure water landing position approaches the center of the top surface from the peripheral edge of the top surface of the substrate W, and from the pure water discharge port 37. When the pure water supply device 36 is controlled so that the discharge flow rate of the pure water increases, the amount of pure water supplied per unit area of the substrate W is the center of the substrate W by the synergistic action of both. As it gets closer to the part, it increases rapidly.

  Further, the control device 3 controls the heater moving means 33 so that the substrate traverse speed increases as the pure water landing position moves away from the center of the upper surface of the substrate W, and the pure water from the pure water discharge port 37 is also controlled. When the pure water supply device 36 is controlled so as to reduce the discharge flow rate, the amount of pure water supplied per unit area of the substrate W is such that the pure water nozzle 38 moves away from the center of the substrate W due to the synergistic effect of both. It will decrease rapidly as it approaches.

FIG. 8 is a graph showing the relationship between the temperature of the phosphoric acid aqueous solution supplied to the substrate W, the etching rate, and the etching selectivity.
As shown in FIG. 8, the etching rate of LP-SiN, which is an example of a silicon nitride film, increases at an accelerated rate as the temperature of the phosphoric acid aqueous solution increases. On the other hand, the etching rate of LP-TEOS, which is an example of a silicon oxide film, is almost zero when the temperature of the phosphoric acid aqueous solution is 140 ° C. or lower. The etching rate of LP-TEOS gradually increases as the temperature of the phosphoric acid aqueous solution increases in the range from 140 ° C. to 170 ° C., and the temperature of the phosphoric acid aqueous solution ranges from 170 ° C. or higher. Then, it increases at an accelerated speed with the temperature rise of phosphoric acid aqueous solution. When the temperature of the phosphoric acid aqueous solution is increased, the etching rate of the silicon nitride film is increased accordingly, but the silicon oxide film is also etched when the temperature of the phosphoric acid aqueous solution is 140 ° C. or higher. As a result, the etching selectivity is lowered. Therefore, by setting the temperature of the phosphoric acid aqueous solution to a predetermined temperature (preferably 140 ° C.) within the range of 120 ° C. to 160 ° C., the etching rate can be increased while maintaining a high etching selectivity.

  In the first embodiment, a small amount of pure water is supplied to the liquid film of phosphoric acid aqueous solution. More specifically, the supply flow rate of pure water to the substrate W is such that the phosphoric acid aqueous solution is not discharged from the substrate W by the pure water flow rate adjustment valve 41, in other words, a liquid film of a paddle-like phosphoric acid aqueous solution on the substrate W. Is set to a value that is retained. Therefore, it is possible to prevent the phosphoric acid aqueous solution having sufficient activity from being discharged from the substrate W. Thereby, phosphoric acid aqueous solution can be used efficiently. Furthermore, since there is little pure water supplied to the phosphoric acid aqueous solution on the board | substrate W, the change of the density | concentration and temperature of phosphoric acid aqueous solution can be suppressed. Thereby, the fluctuation | variation of an etching rate can be suppressed.

  In the first embodiment, pure water in an amount corresponding to the amount of water evaporated from the liquid film of the phosphoric acid aqueous solution is supplied to the liquid film of the phosphoric acid aqueous solution. That is, pure water is replenished to the liquid film of the phosphoric acid aqueous solution by the amount evaporated. Therefore, pyrophosphoric acid in the phosphoric acid aqueous solution is reduced by the reaction with the supplied pure water, and the concentration change of the phosphoric acid aqueous solution due to the supply of pure water is substantially prevented. Furthermore, since there is little pure water supplied to the phosphoric acid aqueous solution on the board | substrate W, the change of the density | concentration and temperature of phosphoric acid aqueous solution can be suppressed. Thereby, the fluctuation | variation of an etching rate can be suppressed, suppressing the fall of an etching selectivity.

  In the first embodiment, pure water droplets are discharged one by one from the pure water discharge port 37 toward the upper surface of the substrate W, not in the form of a mist. That is, pure water droplets are intermittently discharged from the pure water discharge port 37. The pure water droplets deposited on the phosphoric acid aqueous solution on the substrate W move in the phosphoric acid aqueous solution toward the interface between the substrate W and the phosphoric acid aqueous solution while solidifying. Since pure water does not immediately diffuse in the phosphoric acid aqueous solution, a relatively large amount of pure water can reach the interface between the substrate W and the phosphoric acid aqueous solution. As a result, pyrophosphoric acid present at the interface between the substrate W and the phosphoric acid aqueous solution can be reduced, so that a decrease in the etching selectivity can be suppressed or prevented.

  In the first embodiment, the infrared rays emitted from the infrared heater 31 are applied to the substrate W, and radiant heat is transmitted from the infrared heater 31 to the substrate W. Thereby, the substrate W is heated. Therefore, the phosphoric acid aqueous solution on the substrate W is heated. Alternatively, the infrared heats the phosphoric acid aqueous solution directly. The infrared heater 31 emits infrared rays in a state where at least a part of the infrared heater 31 is in contact with the liquid film of the phosphoric acid aqueous solution. Therefore, evaporation of water from the phosphoric acid aqueous solution is suppressed by the infrared heater 31. Thereby, the density | concentration change of phosphoric acid aqueous solution can be suppressed. Furthermore, generation of pyrophosphoric acid in the phosphoric acid aqueous solution can be suppressed. Therefore, it is possible to prevent the etching selectivity from decreasing while stabilizing the etching rate.

  In the first embodiment, the phosphoric acid aqueous solution on the substrate W is heated to the boiling point by the heating device 10. Thereby, the etching rate of the silicon nitride film can be increased. Although the evaporation amount of water from the phosphoric acid aqueous solution increases, the concentration of the phosphoric acid aqueous solution greatly changes because the pure water supply device 36 replenishes the phosphoric acid aqueous solution with pure water corresponding to the evaporation amount. There is no. Therefore, the etching rate can be stabilized.

In the first embodiment, the substrate W is heated to a temperature not lower than the boiling point of the phosphoric acid aqueous solution. Therefore, the temperature of the upper surface of the substrate W in contact with the phosphoric acid aqueous solution rises to a temperature equal to or higher than the boiling point of the phosphoric acid aqueous solution. Therefore, the phosphoric acid aqueous solution can be maintained in a boiling state at the interface between the substrate W and the phosphoric acid aqueous solution. Thereby, an etching rate can be raised.
In the first embodiment, the heater moving device 33 moves the infrared heater 31 and the pure water nozzle 38 in a state where the positional relationship between the pure water landing position and the infrared irradiation position is kept constant. At this time, the heater moving device 33 moves the infrared heater 31 so that the region adjacent to the pure water landing position is heated by the infrared heater 31. Therefore, the vicinity of the pure water landing position is heated by the infrared heater 31. Therefore, even if the temperature of the substrate W and the phosphoric acid aqueous solution changes due to the supply of pure water, the time for the substrate W and the phosphoric acid aqueous solution to return to the original temperature can be shortened. Thereby, the fall of the uniformity of etching can be controlled.

  In the first embodiment, the heater moving device 33 moves the infrared heater 31 with respect to the rotation direction Dr of the substrate W so that a region downstream from the pure water landing position on the upper surface of the substrate W is heated. Therefore, the area where the pure water is deposited (a part of the substrate W) is immediately moved to the heating area (infrared irradiation area) by the rotation of the substrate W, and is heated by the infrared heater 31. For this reason, even if the temperatures of the substrate W and the phosphoric acid aqueous solution are temporarily lowered due to the supply of pure water, the temperatures of the substrate W and the phosphoric acid aqueous solution can be restored to each other in a short time. Thereby, the fall of the uniformity of etching can be controlled.

  Further, in the first embodiment, the control device 3 determines that the pure water landing position crosses the substrate W and moves from the peripheral edge of the substrate toward the central portion according to the rotation speed of the substrate W (or the substrate center across the substrate W). The speed from the portion toward the peripheral edge of the substrate. Specifically, when the rotation speed of the substrate W is less than a predetermined speed, the control device 3 moves the liquid landing position between the central portion of the upper surface of the substrate W and the peripheral portion of the upper surface of the substrate W at a constant substrate traverse speed. Let On the other hand, when the rotation speed of the substrate W is equal to or higher than the predetermined speed, the control device 3 decreases the landing speed of the substrate at the liquid landing position as the liquid landing position approaches the center of the upper surface from the peripheral edge of the substrate W or the landing position. As the liquid position moves away from the center of the upper surface of the substrate, the substrate traversing speed at the liquid landing position is increased. Therefore, when the rotation speed of the substrate W is equal to or higher than the predetermined speed, more pure water than the pure water supplied to the peripheral edge of the upper surface of the substrate W is supplied to the central portion of the upper surface of the substrate W.

  The inventors of the present application have confirmed a phenomenon in which the etching amount at the central portion of the upper surface of the substrate W becomes larger than the etching amount at the peripheral portion of the upper surface of the substrate W when the rotation speed of the substrate W is high. This difference in etching amount is considered to be because the concentration of the phosphoric acid aqueous solution at the center of the upper surface of the substrate W is higher than the concentration of the phosphoric acid aqueous solution at the peripheral edge of the upper surface of the substrate W. Therefore, the control device 3 supplies more pure water to the center of the upper surface of the substrate W than the pure water supplied to the periphery of the upper surface of the substrate W, so that the phosphoric acid aqueous solution at the center of the upper surface of the substrate W The concentration can be reduced. Thereby, the control apparatus 3 can prevent the increase in the etching amount in the upper surface center part of the board | substrate W, and can improve the in-plane uniformity of an etching by this.

Second Embodiment Next, a second embodiment of the present invention will be described. The main difference between the second embodiment and the first embodiment is that the processing unit 2 further includes a humidifier 242. 9 and 10, the same components as those shown in FIGS. 1 to 8 described above are denoted by the same reference numerals as those in FIG. 1 and the description thereof is omitted.

FIG. 9 is a schematic view of the infrared heater 231 and the spin chuck 5 according to the second embodiment of the present invention viewed horizontally. FIG. 10 is a longitudinal sectional view of an infrared heater 231 according to the second embodiment of the present invention.
The processing unit 2 according to the second embodiment further includes a humidifier 242 that discharges a humidified gas having a higher humidity than the humidity in the chamber 4 above the substrate W. The humidifier 242 includes a humidifying nozzle 250 that discharges the humidified gas above the substrate W. The humidifying nozzle 250 may be a nozzle integrated with the infrared heater 31 or may be a nozzle different from the infrared heater 31. 9 and 10 show an example in which the humidifying nozzle 250 is integrated with the infrared heater 31.

  The heating apparatus 10 includes an infrared heater 231 instead of the infrared heater 31 according to the first embodiment. The infrared heater 231 includes an infrared lamp 234 that emits infrared light, and a lamp housing 235 that houses the infrared lamp 234. The infrared lamp 234 is disposed in the lamp housing 235. The lamp housing 235 is smaller than the substrate W in plan view. Therefore, the infrared heater 231 disposed in the lamp housing 435 is also smaller than the substrate W in plan view. The infrared lamp 234 and the lamp housing 235 are attached to the heater arm 32. Therefore, the infrared lamp 234 and the lamp housing 235 rotate around the rotation axis A3 (see FIG. 1) together with the heater arm 32.

  Infrared lamp 234 includes a filament and a quartz tube that houses the filament. As shown in FIG. 10, the infrared lamp 234 includes a ring-shaped end portion 243a disposed along the horizontal plane, and a pair of vertical portions 243b extending upward from one end and the other end of the ring-shaped portion 243a. . The infrared lamp 234 (for example, a halogen lamp) may be a carbon heater or a heating element other than these. At least a part of the lamp housing 235 is formed of a material having optical transparency and heat resistance such as quartz.

  When the infrared lamp 234 emits light, the infrared lamp 234 emits light including infrared rays. The light containing infrared rays is transmitted through the lamp housing 235 and emitted from the outer surface of the lamp housing 235, or the lamp housing 235 is heated to emit radiant light from the outer surface. The liquid film of the phosphoric acid aqueous solution held on the substrate W and its upper surface is heated by transmitted light and radiated light from the outer surface of the lamp housing 235. As described above, light including infrared rays is radiated from the outer surface of the lamp housing 235 by transmission or radiation. Hereinafter, the infrared lamp 234 will be described by focusing on the infrared rays that pass through the outer surface of the lamp housing 235. .

  The lamp housing 235 includes a transmission member that transmits infrared rays. As shown in FIG. 10, the transmission member includes a cylindrical storage portion 244 that extends in the vertical direction, a disk-shaped bottom plate portion 245 that closes the lower end of the storage portion 244, and a vertical direction along the center line of the storage portion 244. A central tube 246 that extends downward from the bottom surface of the bottom plate portion 245 and a disc-shaped counter plate 247 that is disposed below the bottom plate portion 245 and supported by the lower end of the central tube 246. The lamp housing 235 further includes a lid member 248 that closes the upper end of the housing portion 244 and a support member 249 that supports the pair of vertical portions 243 b of the infrared lamp 234. The infrared lamp 234 is supported by the lid member 248 via the support member 249.

  As shown in FIG. 10, the annular portion 243 a of the infrared lamp 234 is disposed in a cylindrical space defined by the accommodating portion 244, the bottom plate portion 245, and the central tube 246. An annular portion 243 a of the infrared lamp 234 surrounds the central tube 246 inside the accommodating portion 244. The bottom plate portion 245 is disposed below the infrared lamp 234 and faces the infrared lamp 234 in the vertical direction with a space therebetween. Similarly, the opposing plate 247 is disposed below the bottom plate portion 245 and faces the bottom plate portion 245 in the vertical direction with a space therebetween. The bottom plate portion 245 and the counter plate 247 have the same outer diameter. The lower surface of the bottom plate portion 245 and the upper surface of the counter plate 247 are parallel to each other and are opposed to each other in the vertical direction with a space therebetween.

  Infrared rays from the infrared lamp 234 are transmitted downward through the bottom plate portion 245 and the opposing plate 247 made of quartz, and are emitted downward from the lower surface of the opposing plate 247. The lower surface of the counter plate 247 includes a flat irradiation surface that is parallel to the upper surface of the substrate W. In a state where the infrared heater 231 is disposed above the substrate W, the irradiation surface of the lamp housing 235 faces the upper surface of the substrate W in the vertical direction with a space therebetween. When the infrared lamp 234 emits infrared light in this state, the infrared light transmitted through the lamp housing 235 is irradiated from the irradiation surface of the lamp housing 235 toward the upper surface of the substrate W and is irradiated onto the upper surface of the substrate W. Thereby, radiant heat is transmitted from the infrared lamp 234 to the substrate W, and the substrate W is heated.

  As shown in FIG. 10, the humidifier 242 includes a humidifying nozzle 250 composed of a bottom plate portion 245 and a counter plate 247, a humidified gas pipe 251 that supplies humidified gas to the central pipe 246, and a central pipe from the humidified gas pipe 251. A humidified gas valve 252 that switches between supply and stop of supply of the humidified gas to the H.246. The lower end of the center tube 246 is blocked by the counter plate 247. The center tube 246 includes a plurality of (for example, eight) through holes 253 disposed at a height between the lower surface of the bottom plate portion 245 and the upper surface of the counter plate 247. The plurality of through holes 253 extend from the inner peripheral surface of the central tube 246 to the outer peripheral surface of the central tube 246 and open at the outer peripheral surface of the central tube 246. The plurality of through holes 253 are arranged at intervals in the circumferential direction. The humidifying nozzle 250 includes an annular discharge port 254 formed by the outer peripheral portion of the bottom plate portion 245 and the outer peripheral portion of the counter plate 247. The annular discharge port 254 is continuous over the entire circumference and is disposed around the plurality of through holes 253.

  When the humidified gas valve 252 is opened, the humidified gas supplied from the humidified gas pipe 251 to the central tube 246 is discharged from the plurality of through holes 253 to the periphery of the central tube 246, and the lower surface of the bottom plate portion 245 and the upper surface of the opposing plate 247 To the outside in the radial direction of the substrate W. Then, the humidified gas that has reached the outer peripheral portions of the bottom plate portion 245 and the counter plate 247 is discharged horizontally from the annular discharge port 254. As a result, an air flow of humidified gas extending radially from the annular discharge port 254 is formed. The humidified gas is water vapor below 100 ° C. The humidified gas is not limited to water vapor, but may be mist of pure water (a mist of pure water at room temperature) or superheated steam at 100 ° C. or higher.

  When the substrate W is processed by the processing unit 2, the control device 3 (see FIG. 1) performs the humidification process in which water vapor, which is an example of the humidification gas, is discharged in the chamber 4 in the above-described radiation heating process and pure water supply process. And in parallel with the paddle process. Specifically, before moving the infrared heater 231 and the pure water nozzle 38 above the substrate W, the control device 3 opens the humidified gas valve 252 and starts discharging water vapor from the humidified nozzle 250. Thereby, the humidity in the chamber 4 increases, and the water vapor pressure approaches the saturated water vapor pressure. Further, since the discharge of the water vapor from the humidifying nozzle 250 continues after the control device 3 moves the infrared heater 231 and the pure water nozzle 38 above the substrate, the atmosphere above the substrate W is brought close to the saturated water vapor pressure. be able to. In this embodiment, the water vapor is discharged from the humidifying nozzle 250 before the start of the infrared ray from the infrared heater 231. However, the water vapor is discharged from the humidifying nozzle 250 after the infrared ray irradiation from the infrared heater 231 is started. You may make it do.

  After the infrared heater 231 and the pure water nozzle 38 are arranged above the substrate W, the controller 3 controls the heater so that the irradiation position of the infrared rays with respect to the upper surface of the substrate W moves from one of the central portion and the peripheral portion to the other. The infrared heater 231 and the pure water nozzle 38 are moved horizontally by the moving device 33. At this time, the control device 3 may move the infrared heater 231 while the lower surface of the counter plate 247 is in contact with the phosphoric acid aqueous solution film on the substrate W, or the lower surface of the infrared heater 231 is the substrate. The infrared heater 231 may be moved while being separated from the liquid film of the phosphoric acid aqueous solution on W by a predetermined distance.

  The control device 3 opens and closes the pure water valve 40 a plurality of times while the infrared irradiation position moves between the central portion of the upper surface of the substrate W and the peripheral portion of the upper surface of the substrate W. Thereby, the pure water landing position moves between the center of the upper surface of the substrate W and the peripheral edge of the upper surface of the substrate W, and the pure water is preferably intermittently supplied from the pure water discharge port 37 of the pure water nozzle 38. In this case, a plurality of droplets of pure water are ejected one by one. Accordingly, a plurality of pure water droplets are supplied to a plurality of positions in the upper surface of the substrate W in a state where the discharge of the phosphoric acid aqueous solution from the substrate W is stopped. After the heating of the substrate W by the infrared heater 231 is performed for a predetermined time, the control device 3 stops the discharge of the liquid droplets from the pure water nozzle 38 and moves the infrared heater 231 and the pure water nozzle 38 above the substrate W. Evacuate from. Thereafter, the control device 3 stops the emission of the infrared heater 231 and the discharge of water vapor from the humidifying nozzle 250. The discharge of water vapor from the humidifying nozzle 250 may be stopped before the infrared heater 231 stops emitting infrared rays, or may be stopped after the infrared heater 231 stops emitting infrared rays.

  As described above, the control device 3 discharges the humidified gas having a higher humidity than the humidity in the chamber 4 from the humidifying nozzle 250 in a state where the phosphoric acid aqueous solution on the substrate W is heated. Will increase. Accordingly, the amount of water evaporated from the phosphoric acid aqueous solution is reduced. In particular, in the second embodiment, the humidified gas is discharged radially from the annular discharge port 254, and an air flow of the humidified gas that flows along the upper surface of the substrate W is formed. Covered by. Therefore, the humidity in the vicinity of the substrate W can be reliably increased and the evaporation of water from the phosphoric acid aqueous solution can be efficiently suppressed as compared with the case where the humidified gas is discharged at a position away from the substrate W. Thereby, generation | occurrence | production of pyrophosphoric acid can be suppressed efficiently, and the fall of an etching selectivity can be suppressed.

  As described above, in the second embodiment, the humidified gas having a higher humidity than the humidity in the chamber 4 is supplied into the chamber 4. Thereby, the humidity in the chamber 4 increases, and the water vapor pressure in the chamber 4 rises to a value equal to or lower than the saturated water vapor pressure. Therefore, evaporation of water from the phosphoric acid aqueous solution on the substrate W is suppressed. Therefore, generation of pyrophosphoric acid in the phosphoric acid aqueous solution can be efficiently suppressed, and a decrease in etching selectivity can be suppressed.

In the second embodiment, a humidified gas having a humidity higher than the humidity in the chamber 4 and higher than the atmospheric temperature (room temperature) in the chamber 4 is supplied into the chamber 4. Thereby, while the humidity in the chamber 4 increases, the atmospheric temperature in the chamber 4 increases. Therefore, it is possible to suppress a decrease in etching rate.
In the second embodiment, the humidified gas is discharged radially from the annular discharge port 254 in a direction parallel to the upper surface of the substrate W. As a result, a humidified gas stream radially extending from the annular discharge port 254 is formed above the phosphoric acid aqueous solution liquid film, and the phosphoric acid aqueous solution liquid film is covered with the humidified gas stream. Therefore, the humidity above the liquid film of the phosphoric acid aqueous solution is reliably increased. Thereby, evaporation of water from the phosphoric acid aqueous solution on the substrate W is suppressed. Therefore, generation of pyrophosphoric acid in the phosphoric acid aqueous solution can be suppressed, and a decrease in etching selectivity can be suppressed.

Third Embodiment Next, a third embodiment of the present invention will be described. The main difference between the third embodiment and the first embodiment is that the heating device 10 supplies the heating fluid to the lower surface of the substrate W to heat the substrate W in addition to the radiation heating device according to the first embodiment. A heating fluid supply device. In the following FIG. 11, the same components as those shown in FIGS. 1 to 10 are given the same reference numerals as those in FIG. 1 and the description thereof is omitted.

FIG. 11 is a schematic view of the fluid nozzle 356 and the spin chuck 5 according to the third embodiment of the present invention viewed horizontally.
The heating device 10 according to the third embodiment further includes a heating fluid supply device that heats the substrate W by discharging the heating fluid onto the substrate W and increases the humidity in the chamber 4. The heating fluid supply device includes a fluid nozzle 356 that discharges a heating fluid having a temperature higher than that of the substrate W from the fluid discharge port 355 toward the lower surface of the substrate W, a fluid pipe 357 that supplies the heating fluid to the fluid nozzle 356, and a fluid pipe. And a fluid valve 358 for switching supply and stop of supply of heated fluid from the fluid nozzle 356 to the fluid nozzle 356. The fluid nozzle 356 includes a fluid discharge port 355 that discharges the heated fluid upward.

  The fluid discharge port 355 of the fluid nozzle 356 is disposed between the lower surface of the substrate W and the upper surface of the spin base 14. The fluid discharge port 355 of the fluid nozzle 356 faces the center portion of the lower surface of the substrate W in the vertical direction with a gap. The heating fluid is superheated steam. The heating fluid is not limited to superheated steam, and may be high-temperature pure water (pure water having a temperature higher than that of the substrate W) or high-temperature gas (inert gas or clean air having a temperature higher than that of the substrate W). Good. That is, the heating fluid may be a liquid (heating liquid) or a gas (heating gas).

  When the fluid valve 358 is opened, the heated fluid is discharged from the fluid discharge port 355 of the fluid nozzle 356 toward the center of the lower surface of the substrate W. When the heating fluid is a heating liquid, when the heating liquid is discharged from the fluid discharge port 355 of the fluid nozzle 356 in a state where the substrate W is rotating, the discharged heating fluid collides with the center of the lower surface of the substrate W. After that, due to centrifugal force, it spreads radially along the lower surface of the substrate W from the center of the lower surface of the substrate W to the peripheral edge of the lower surface of the substrate W. When the heating fluid is a heating gas, the heating fluid discharged from the fluid nozzle 356 collides with the center of the lower surface of the substrate W, and then spreads radially between the lower surface of the substrate W and the upper surface of the spin base 14. Then, it diffuses into the space between the substrate W and the spin base 14. Therefore, regardless of whether the heating fluid is a heating liquid or a heating gas, the heating fluid is supplied to the entire lower surface of the substrate W, and the substrate W is uniformly heated over the entire surface.

  When the substrate W is processed by the processing unit 2, the control device 3 (see FIG. 1) directs superheated steam, which is an example of a heating fluid, to the lower surface of the substrate W before the above-described phosphoric acid supply step is started. The heating fluid supply process for discharging is started. Specifically, the control device 3 opens the fluid valve 358 and discharges superheated steam from the fluid nozzle 356 toward the center of the lower surface of the substrate W. The discharge of the superheated steam may be started in a state where the substrate W is rotating, or may be started in a state where the substrate W is not rotating.

  The superheated steam discharged from the fluid nozzle 356 collides with the center of the lower surface of the substrate W, then spreads radially between the lower surface of the substrate W and the upper surface of the spin base 14, and between the substrate W and the spin base 14. Spread in space. Thereby, the superheated steam comes into contact with the entire lower surface of the substrate W and the peripheral end surface of the substrate W, and the heat of the superheated steam is transmitted to the entire lower surface of the substrate W. Thereby, the substrate W is heated uniformly.

  The control device 3 performs the above-described phosphoric acid supply process in a state where the fluid nozzle 356 is discharging superheated steam. Similarly, the control device 3 performs the above-described radiation heating process, pure water supply process, and paddle process while the fluid nozzle 356 is discharging superheated steam. The control device 3 retracts the infrared heater 31 and the pure water nozzle 38 from above the substrate W, and then closes the fluid valve 358 to stop the discharge of superheated steam from the fluid nozzle 356. The discharge of superheated steam from the fluid nozzle 356 may be stopped before the infrared heater 31 stops emitting infrared rays, or may be stopped after the infrared heater 31 stops emitting infrared rays.

  As described above, in the third embodiment, the infrared light emitted from the infrared heater 31 is applied to the upper surface of the substrate W, and the substrate W is heated. Further, the heating fluid discharged from the fluid nozzle 356 is supplied to the entire lower surface of the substrate W, and the entire region of the substrate W is heated. Thus, since the heating fluid having a temperature higher than that of the substrate W is supplied to the entire lower surface of the substrate W, the uniformity of the processing temperature can be improved over the entire surface of the substrate W. Therefore, the uniformity of the temperature of the liquid film of the phosphoric acid aqueous solution can be improved. Therefore, the uniformity of etching can be improved.

  In particular, when superheated steam at 100 ° C. or higher as a heating fluid and humidified gas is discharged from a fluid nozzle 356 as a heating device and supplied to the entire lower surface of the substrate W, the substrate W and the substrate W are heated. The liquid film of phosphoric acid aqueous solution can be heated efficiently. Further, the superheated water vapor on the lower surface of the substrate W goes around from the peripheral end surface of the substrate W to the upper surface of the substrate W or diffuses around the spin chuck 5 holding the substrate W, so that the chamber 4 can be in a humidified state. Therefore, evaporation of water from the phosphoric acid aqueous solution on the substrate W is suppressed. Therefore, pyrophosphoric acid in the phosphoric acid aqueous solution can be reduced, and a decrease in etching selectivity can be suppressed.

Fourth Embodiment Next, a fourth embodiment of the present invention will be described. The main difference between the fourth embodiment and the first embodiment is that a pure water discharge port 37 for discharging pure water is provided at the center of the lower surface of the infrared heater 431. In the following FIG. 12, the same components as those shown in FIGS. 1 to 11 are given the same reference numerals as those in FIG. 1 and the description thereof is omitted.

FIG. 12 is a schematic diagram showing a longitudinal section and a bottom surface of the infrared heater 431 and the pure water nozzle 38 according to the fourth embodiment of the present invention.
The heating apparatus 10 according to the fourth embodiment includes an infrared heater 431 instead of the infrared heater 31 according to the first embodiment. The infrared heater 431 includes an infrared lamp 234 that emits infrared light, and a lamp housing 435 that houses the infrared lamp 234. The infrared lamp 234 is disposed in the lamp housing 435. The lamp housing 435 is smaller than the substrate W in plan view. Accordingly, the infrared heater 431 disposed in the lamp housing 435 is smaller than the substrate W in plan view. The infrared lamp 234 and the lamp housing 435 are attached to the heater arm 32 (see FIG. 1). Therefore, the infrared lamp 234 and the lamp housing 435 rotate around the rotation axis A3 (see FIG. 1) together with the heater arm 32. In the heating and pure water supply step S4 of the first embodiment, the pure water landing position moves only between the center position of the upper surface of the substrate W and the one peripheral edge position of the substrate W (range indicated by the arrow in FIG. 3). Thus, the heater arm 32 was rotated. However, in the fourth embodiment, the rotation range of the heater arm 32 in the heating and pure water supply step S4 is expanded so that the pure water landing position moves between the two peripheral positions of the substrate W.

  Infrared lamp 234 includes a filament and a quartz tube that houses the filament. The infrared lamp 234 includes a ring-shaped end portion 243a disposed along a horizontal plane, and a pair of vertical portions 243b extending upward from one end and the other end of the ring-shaped portion 243a. The infrared lamp 234 as a heating means (for example, a halogen lamp) may be a carbon heater, or a heating element other than these. At least a part of the lamp housing 435 is formed of a material having optical transparency and heat resistance such as quartz.

  When the infrared lamp 234 emits light, the infrared lamp 234 emits light including infrared rays. The light including infrared rays is transmitted through the lamp housing 435 and emitted from the outer surface of the lamp housing 435, or the lamp housing 435 is heated to emit radiant light from the outer surface. The liquid film of the phosphoric acid aqueous solution held on the substrate W and its upper surface is heated by transmitted light and radiated light from the outer surface of the lamp housing 435. As described above, light including infrared rays is radiated from the outer surface of the lamp housing 435 by transmission or radiation. Hereinafter, the infrared lamp 234 will be described by focusing on the infrared rays transmitted through the outer surface of the lamp housing 435. . The lamp housing 435 includes a transmission member that transmits infrared rays. The transmission member extends in the vertical direction along the center line of the cylindrical housing portion 244 that extends in the vertical direction, the disk-shaped bottom plate portion 245 that closes the lower end of the storage portion 244, and the bottom plate portion. And a central tube 246 that opens at the center of the lower surface of H.245. The lamp housing 435 further includes a lid member 248 that closes the upper end of the housing portion 244 and a support member 249 that supports the pair of vertical portions 243 b of the infrared lamp 234. The infrared lamp 234 is supported by the lid member 248 via the support member 249.

  The annular portion 243 a of the infrared lamp 234 is disposed in a cylindrical space defined by the housing portion 244, the bottom plate portion 245, and the central tube 246. An annular portion 243 a of the infrared lamp 234 surrounds the central tube 246 inside the accommodating portion 244. The bottom plate portion 245 is disposed below the infrared lamp 234 and faces the infrared lamp 234 in the vertical direction with a space therebetween. The pure water nozzle 38 is inserted into the central tube 246. The pure water discharge port 37 of the pure water nozzle 38 is disposed in the central tube 246. As shown on the lower side of FIG. 12, when the infrared heater 431 is viewed from below, the pure water discharge port 37 is surrounded by the lower surface of the bottom plate portion 245 as an irradiation surface. Therefore, pure water droplets discharged from the pure water nozzle 38 are discharged from the lower surface of the bottom plate portion 245.

  According to this configuration, since pure water droplets are ejected from the irradiation surface of the infrared heater 431, the pure water landing position is surrounded by the infrared irradiation position. Therefore, when the pure water discharge port 37 discharges pure water droplets in a state where the substrate W is rotating and the infrared heater 431 emits infrared light, the region where the pure water droplets have landed is the substrate. Whatever region is in the upper surface of W, this region is immediately moved to the irradiation position and heated. Therefore, even if the infrared heater 431 and the pure water nozzle 38 move between two positions where the pure water droplets land on the upper peripheral edge of the substrate W, the region where the pure water droplets have landed remains. It is heated immediately. Thereby, the fluctuation | variation of the temperature of the board | substrate W can be suppressed.

Fifth Embodiment Next, a fifth embodiment of the present invention will be described. The main difference between the fifth embodiment and the first embodiment is that the pure water supply device 36 further includes a pure water temperature adjusting device 559 for adjusting the temperature of pure water discharged from the pure water nozzle 38. That is. In the following FIG. 13, the same components as those shown in FIGS. 1 to 12 described above are denoted by the same reference numerals as those in FIG. 1 and the description thereof is omitted.

FIG. 13 is a schematic view of a pure water supply device 36 according to the fifth embodiment of the present invention.
In addition to the pure water nozzle 38, the pure water pipe 39, the pure water valve 40, and the pure water flow rate adjustment valve 41, the pure water supply device 36 has a temperature of pure water supplied from the pure water pipe 39 to the pure water nozzle 38. A pure water temperature adjusting device 559 is further included. The pure water temperature adjustment device 559 includes a temperature controller 560 (at least one of a heater and a cooler) that adjusts the temperature of pure water flowing in the pure water pipe 39. FIG. 13 shows an example in which both the heater and the cooler are provided in the pure water temperature adjusting device 559. The pure water temperature adjusting device 559 may further include a temperature sensor 561 that detects the temperature of the pure water whose temperature has been adjusted by the temperature controller 560.

  According to this configuration, pure water droplets whose temperature is adjusted by the pure water temperature adjusting device 559 are supplied to the substrate W in the pure water supply step described above. If the temperature of the pure water is too high, the pure water may evaporate before reaching the interface between the substrate W and the phosphoric acid aqueous solution. On the other hand, if the temperature of pure water is too low, the temperature of the phosphoric acid aqueous solution on the substrate W may change significantly. Therefore, the droplets of pure water whose temperature is adjusted by the pure water temperature adjusting device 559 are discharged from the pure water nozzle 38, thereby suppressing fluctuations in the temperature of the phosphoric acid aqueous solution on the substrate W and phosphorous. Pure water can reach the interface with the acid aqueous solution. When the temperature sensor 561 is provided in the pure water temperature adjustment device 559, the control device 3 can adjust the temperature of the temperature adjuster 560 based on the detected value of the temperature sensor 561. Therefore, the control device 3 can control the temperature of pure water supplied to the substrate W more precisely.

Other Embodiments Although the description of the first to fifth embodiments of the present invention has been described above, the present invention is not limited to the contents of the first to fifth embodiments described above, and the scope of the claims. Various modifications can be made within.
For example, in the first to fifth embodiments, the case where the infrared heater 31 including the infrared lamp 34 is used as a heater has been described. However, another heating element such as a heating wire is used as a heating unit that heats the substrate W. It may be used instead of the infrared lamp 34.

In the first to fifth embodiments, the case where the spin chuck 5 that holds and rotates the substrate W horizontally is used as the substrate holding device has been described. However, the processing unit 2 is replaced with the spin chuck 5. A substrate holding device that holds the substrate W horizontally in a stationary state may be provided.
In the first to fifth embodiments, the case where the infrared heater 31 and the pure water nozzle 38 are attached to a common movable arm (heater arm 32) has been described. It may be attached to separate movable arms. That is, the deionized water supply device 36 includes a deionized water nozzle that moves the deionized water nozzle by moving the nozzle arm (movable arm different from the heater arm 32) with the deionized water nozzle attached to the tip. And a mobile device. In this case, the positional relationship between the infrared irradiation position and the pure water landing position may not be constant. Moreover, the phosphoric acid nozzle 18, the infrared heater 31, and the pure water nozzle 38 may be attached to a common movable arm (for example, the heater arm 32). In the fourth embodiment, since the pure water nozzle 38 is disposed in the infrared heater 431, the pure water nozzle 38 and the infrared heater 431 are attached to the same movable arm (heater arm 32).

  In the first, second, third and fifth embodiments, the control device 3 includes a center position where the pure water landing position is located at the center of the upper surface of the substrate W, and a pure water landing position. Although the case where the infrared heater 31 and the pure water nozzle 38 are rotated between the edge positions positioned on the peripheral edge of the upper surface of the substrate W has been described, the control device 3 does not use the pure water discharged from the pure water nozzle 38. The infrared heater 31 and the pure water nozzle 38 may be moved between two edge positions where the liquid droplets land on the peripheral edge of the upper surface of the substrate W.

  In the first, second, third and fifth embodiments, the case where the pure water nozzle 38 is attached to the heater arm 32 on the distal end side of the heater arm 32 relative to the infrared heater 31 has been described. The pure water nozzle 38 may be attached to the heater arm 32 on the base side of the heater arm 32 relative to the infrared heater 31. Further, the infrared heater 31 and the pure water nozzle 38 may be arranged at a position where the distance from the rotation axis A <b> 3 is equal in plan view, and may be arranged in the rotation direction of the heater arm 32.

In the first to fifth embodiments, the case where pure water droplets are formed by opening and closing the pure water valve 40 has been described. However, the pure water nozzle 38 is a pure water valve with the pure water valve 40 open. A piezoelectric element may be provided that divides the pure water discharged from the pure water discharge port 37 by applying vibration to the pure water discharged from the water discharge port 37.
In the first to fifth embodiments, the case where the rotation speed of the substrate W is maintained constant during the period during which the pure water supply process is performed is described. However, during the period during which the pure water supply process is performed. In addition, the rotation speed of the substrate W may be changed.

  Specifically, a low-speed rotation process that rotates the substrate W at a low rotation speed (for example, 1 to 30 rpm) slower than the rotation speed of the substrate W in the phosphoric acid supply process, and a high rotation speed that is faster than the low rotation speed ( For example, the high-speed rotation process of rotating the substrate W at 50 rpm) may be performed in parallel with the pure water supply process. In this case, since the centrifugal force applied to the pure water droplets supplied to the substrate W is increased in the high-speed rotation process, the pure water can be diffused in a wider range within the upper surface of the substrate W in a short time.

  In the first to fifth embodiments, the case where heating of the substrate W by the infrared heater 31 is started after the phosphoric acid aqueous solution is supplied to the substrate W has been described. It may be started before the phosphoric acid aqueous solution is supplied to the substrate W. In this case, since the phosphoric acid aqueous solution is supplied to the substrate W while the substrate W is heated, the time for raising the temperature of the phosphoric acid aqueous solution to a predetermined temperature can be shortened.

  In the first to fifth embodiments, heating of the substrate W by the infrared heater 31 and supply of pure water from the pure water nozzle 38 are performed while supply of the phosphoric acid aqueous solution to the substrate W is stopped. However, the heating of the substrate W by the infrared heater 31 and the supply of pure water from the pure water nozzle 38 may be performed while the phosphoric acid nozzle 18 is discharging the phosphoric acid aqueous solution. . That is, the radiation heating process and the pure water supply process may be performed in parallel with the phosphoric acid supply process. In this case, the paddle process may be omitted.

  In the third embodiment, the case where the fluid nozzle 356 that discharges the heating fluid toward the substrate W is described. However, the case where a hot plate including a heating element is used instead of the spin base 14 is described. The fluid nozzle 356 may be omitted. In this case, since the substrate W is held horizontally by the hot plate while the entire lower surface of the substrate W is in contact with the upper surface of the hot plate, the heat constantly released from the hot plate is uniformly distributed throughout the substrate W. Communicated. Thereby, the substrate W is heated uniformly.

In the first to fifth embodiments, the case where the substrate processing apparatus 1 is an apparatus for processing a disk-shaped substrate W has been described. However, the substrate processing apparatus 1 is a polygonal substrate such as a substrate for a liquid crystal display device. An apparatus for processing the substrate W may be used.
Moreover, two or more of all the embodiments including the first to fifth embodiments may be combined. For example, the humidification process according to the second embodiment and the conductive heating process according to the third embodiment may be performed in parallel.

  In addition, various design changes can be made within the scope of matters described in the claims.

1: substrate processing apparatus 2: processing unit 3: control device (control means)
4: Chamber 5: Spin chuck (substrate holding means)
6: Phosphoric acid supply device (phosphoric acid supply means)
10: Heating device (heating means)
17: Spin motor (substrate rotating means)
31: Infrared heater 33: Heater moving device 34: Infrared lamp 35: Lamp housing 36: Pure water supply device (water supply means)
37: Pure water discharge port 38: Pure water nozzle 41: Pure water flow rate adjusting valve 231: Infrared heater 234: Infrared lamp 235: Lamp housing 242: Humidifier (humidifying means)
254: Annular discharge port 356: Fluid nozzle (humidifying means)
431: Infrared heater 435: Lamp housing W: Substrate

Claims (17)

Substrate holding means for holding the substrate horizontally;
Substrate rotating means for rotating the substrate holding means;
Phosphoric acid supply means for forming a liquid film of a paddle-like phosphoric acid aqueous solution covering the entire upper surface of the substrate by supplying a phosphoric acid aqueous solution to the upper surface of the substrate held by the substrate holding means;
Heating means for heating the substrate in a state where a liquid film of the paddle-like phosphoric acid aqueous solution is held on the substrate;
Water is supplied to the liquid film of the phosphoric acid aqueous solution at a flow rate capable of maintaining the liquid film of the paddle-like phosphoric acid aqueous solution on the substrate, and the liquid film of the paddle-shaped phosphoric acid aqueous solution is formed on the substrate. A substrate processing apparatus including a water supply means for maintaining. Substrate holding means for holding the substrate horizontally;
Phosphoric acid supply means for forming a liquid film of a paddle-like phosphoric acid aqueous solution covering the entire upper surface of the substrate by supplying a phosphoric acid aqueous solution to the upper surface of the substrate held by the substrate holding means;
Heating means for heating the substrate in a state where a liquid film of the paddle-like phosphoric acid aqueous solution is held on the substrate;
And a water supply means for supplying an amount of water corresponding to the amount of water evaporated from the liquid film of the paddle-like phosphoric acid aqueous solution to the liquid film of the paddle-like phosphoric acid aqueous solution by heating by the heating means. Processing equipment. The substrate processing apparatus includes:
And water supply position moving means for moving the substrate radially water supply position relative to the substrate,
Control means for controlling the water supply means, the substrate rotation means, and the water supply position movement means,
The control means is supplied from the water supply means when water is supplied from the water supply means to the liquid film of the phosphoric acid aqueous solution while the substrate held by the substrate holding means is rotated by the substrate rotation means. as the water supply amount of increases in the central portion of the substrate than the peripheral portion of the substrate, controlling the water supply means, the substrate processing apparatus according to claim 1. The substrate processing apparatus includes:
And water supply position moving means for moving between the water supply position the substrate center and the substrate edge relative to the substrate,
Control means for controlling the water supply position moving means,
When the substrate held by the substrate holding means is rotated by the substrate rotating means and water is supplied from the water supply means to the liquid film of the phosphoric acid aqueous solution, the control means as the moving speed of the water supply position is slow at the center portion of the substrate than the peripheral portion of the substrate, controls the water supply position moving means, the substrate processing apparatus according to claim 1.   The substrate processing apparatus includes:
  Substrate rotating means for rotating the substrate holding means;
  Water supply position moving means for moving the water supply position relative to the substrate in the radial direction of the substrate;
  Control means for controlling the water supply means, the substrate rotation means, and the water supply position movement means,
  The control means is supplied from the water supply means when water is supplied from the water supply means to the liquid film of the phosphoric acid aqueous solution while the substrate held by the substrate holding means is rotated by the substrate rotation means. The substrate processing apparatus according to claim 2, wherein the water supply unit is controlled such that the amount of water supplied is greater at a central portion of the substrate than at a peripheral portion of the substrate.   The substrate processing apparatus includes:
  Substrate rotating means for rotating the substrate holding means;
  Water supply position moving means for moving the water supply position for the substrate between the substrate center portion and the substrate peripheral portion;
  Control means for controlling the water supply position moving means,
  When the substrate held by the substrate holding means is rotated by the substrate rotating means and water is supplied from the water supply means to the liquid film of the phosphoric acid aqueous solution, the control means The substrate processing apparatus according to claim 2, wherein the water supply position moving unit is controlled so that a moving speed of the water supply position is slower at a center portion of the substrate than at a peripheral edge portion of the substrate. Said water supply means, said toward the upper surface of the substrate held by the substrate holding means including a water discharge port for intermittently discharging water, the substrate processing apparatus according to any one of claims 1 to 6 . The substrate processing apparatus according to claim 7 , wherein the water supply unit discharges water droplets one by one from the water discharge port toward an upper surface of the substrate held by the substrate holding unit. Said heating means, said phosphoric acid supply means is a means for heating the substrate before supplying the aqueous solution of phosphoric acid to the upper surface of the substrate, the substrate processing apparatus according to any one of claims 1-8. The heating means includes an infrared heater that irradiates the substrate with infrared rays, and emits infrared rays from the infrared heater in a state where at least a part of the infrared heater is in contact with a liquid film of the phosphoric acid aqueous solution. the substrate processing apparatus according to any one of 1-9. It said heating means, by heating the substrate, heating the liquid film of the aqueous solution of phosphoric acid to the boiling point of the aqueous solution of phosphoric acid, a substrate processing apparatus according to any one of claims 1-10. The substrate processing apparatus according to claim 11 , wherein the heating unit raises the temperature of the substrate to a temperature equal to or higher than a boiling point of the phosphoric acid aqueous solution. The substrate according to any one of claims 1 to 12 , further comprising a chamber for housing the substrate holding means, and a humidifying means for supplying a humidified gas having a humidity higher than the humidity in the chamber into the chamber. Processing equipment. The substrate processing apparatus according to claim 13 , wherein the humidifying unit supplies the humidified gas having a temperature higher than an atmospheric temperature in the chamber into the chamber. The humidifying means includes an annular discharge port that discharges the humidified gas radially in a direction parallel to the upper surface of the substrate, and discharges the humidified gas to the annular discharge port above the liquid film of the phosphoric acid aqueous solution. This forms a stream of the humidified gas radiating from the annular discharge opening above the liquid film of the aqueous solution of phosphoric acid, a substrate processing apparatus according to claim 13 or 14. Said heating means, an infrared heater for irradiating infrared rays on an upper surface of the substrate, a high temperature heating fluid than the substrate and a fluid nozzle for supplying the entire lower surface of the substrate, any of claims 1 to 15 one The substrate processing apparatus according to item. The substrate processing apparatus according to claim 16 , wherein the fluid nozzle discharges superheated steam toward a lower surface of the substrate.

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