JP6642868B2 - Substrate processing method and substrate processing apparatus - Google Patents

Description

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

In a semiconductor device manufacturing process, the surface of a substrate such as a semiconductor wafer is treated with a treatment liquid. A single-wafer-type substrate processing apparatus that processes substrates one by one supplies a spin chuck that rotates the substrate while holding the substrate substantially horizontally, and supplies a processing liquid to the surface of the substrate that is rotated by the spin chuck. And a nozzle for
In a typical substrate processing step, a chemical solution is supplied to a substrate held by a spin chuck. Thereafter, water is supplied to the substrate, whereby the chemical on the substrate is replaced with water. After that, a spin dry process for removing water on the substrate is performed. In the spin-drying step, water adhering to the substrate is shaken off and removed (dried) by rotating the substrate at high speed. Common water is deionized water.

  In the case where a fine pattern is formed on the surface of the substrate, there is a possibility that water entering the inside of the pattern may not be removed in the spin-drying step, which may cause poor drying. Therefore, an organic solvent such as isopropyl alcohol (IPA) is supplied to the surface of the substrate after the treatment with water, and the water entering the gaps in the pattern on the surface of the substrate is replaced with the organic solvent. Techniques for drying the surface have been proposed.

As shown in FIG. 13, in a spin-drying step of drying a substrate by high-speed rotation of the substrate, a liquid surface (an interface between air and liquid) is formed in the pattern. In this case, the surface tension of the liquid acts on the contact position between the liquid surface and the pattern. This surface tension is one of the causes of pattern collapse.
When a liquid of an organic solvent (hereinafter, simply referred to as “organic solvent”) is supplied to the surface of the substrate after the rinsing process and before the spin dry process as in Patent Literature 1, the organic solvent enters between the patterns. The surface tension of organic solvents is lower than water, which is a typical water. Therefore, the problem of pattern collapse caused by surface tension is reduced.

JP-A-9-38595

Although the low surface tension liquid (organic solvent) has hydrophilicity, the substitution performance for the treatment liquid (water) is not so high. Therefore, only supplying the low surface tension liquid requires a long time to completely replace the processing liquid on the surface of the substrate with the low surface tension liquid. As a result of the long time required for the replacement with the low surface tension liquid, the drying time of the surface of the substrate may be prolonged.
Therefore, an object of the present invention is to completely replace the processing liquid on the surface of the substrate with a low surface tension liquid in a short time, thereby drying the substrate surface in a short time while suppressing the collapse of the pattern. An object of the present invention is to provide a processing method and a substrate processing apparatus.

An invention according to claim 1 for achieving the above object is a substrate processing method for processing a surface of a substrate using a processing liquid , wherein the substrate is horizontally oriented with the surface of the substrate facing upward. A substrate holding step of holding the processing liquid, and supplying a low surface tension liquid having a higher boiling point and a lower surface tension than the processing liquid to the surface of the substrate where the processing liquid remains. on the surface of the substrate, before and mixture liquid film forming step of the a Kisho management solution to form a liquid film of the liquid mixture of low surface tension liquids, the liquid of the mixed solution is formed on the surface of the substrate Evaporating the treatment liquid from the film , replacing the mixed liquid at least at the interface between the liquid film of the mixed liquid and the surface of the substrate with the low surface tension liquid, and replacing the low surface tension liquid with the low surface tension liquid. Removed from the surface of the substrate, Look including a drying step of drying the surface, the replacement step, the mixing the treatment liquid contained in the liquid film of the liquid mixture to evaporate, after covering the surface of the substrate by the liquid film of the liquid mixture the mixture heating step of heating the liquid in the liquid film providing including, a substrate processing method.

According to this method, the low surface tension liquid is supplied to the surface of the substrate where the processing liquid remains. As a result, the processing liquid and the low surface tension liquid are mixed, and a mixed liquid is formed on the surface of the substrate. Then, the processing liquid having a low boiling point contained in the mixed liquid evaporates, and as a result, the processing liquid on the surface of the substrate can be completely replaced with the low surface tension liquid.
A liquid mixture is formed by supplying a low surface tension liquid, and the processing liquid contained in the mixture is evaporated to leave only the low surface tension liquid, so that the replacement speed of the processing liquid with the low surface tension liquid is increased. Can be. Thereby, the processing liquid on the surface of the substrate can be completely replaced with the low surface tension liquid in a short time. Therefore, the surface of the substrate can be dried in a short time while suppressing collapse of the pattern.

In this specification, "the processing liquid remains on the surface of the substrate" refers to a state where a liquid film of the processing liquid is formed on the surface of the substrate or a droplet of the processing liquid is present on the surface of the substrate. In addition to the state in which the processing liquid is not present, there is no liquid film or droplet on the surface of the substrate, but the state in which the processing liquid enters the pattern on the surface of the substrate .

Further , a low surface tension liquid is supplied to the upper surface of the substrate held in a horizontal posture. As a result, the processing liquid and the low surface tension liquid are mixed, and a liquid film of the mixed liquid is formed on the surface of the substrate. Then, by heating the liquid film of the mixed liquid, the processing liquid having a low boiling point contained in the liquid film of the mixed liquid can be evaporated. As a result, the treatment liquid in the liquid film can be completely replaced with a low surface tension liquid.

The invention according to claim 2, wherein the mixture heating step, heating the mixture at a low predetermined temperature higher than the boiling point of high and the low surface tension liquid than the boiling point of the treatment liquid, to claim 1 It is a substrate processing method of description.
According to this configuration, if the mixed liquid is heated at a temperature higher than the boiling point of the processing liquid and lower than the boiling point of the low surface tension liquid, the low surface tension liquid in the mixed liquid hardly evaporates. On the other hand, evaporation of the processing liquid in the mixed liquid is promoted. That is, only the processing liquid in the mixed liquid can be efficiently evaporated. Thereby, the complete replacement with the low surface tension liquid can be realized in a shorter time. After the mixed liquid heating step, a liquid film of a low surface tension liquid having a predetermined thickness can be held on the upper surface of the substrate.

According to a third aspect of the present invention, there is provided a substrate processing method for processing a surface of a substrate using a processing liquid, wherein the substrate is horizontally positioned with the surface of the substrate facing upward. A substrate holding step of holding the processing liquid, and supplying a low surface tension liquid having a higher boiling point and a lower surface tension than the processing liquid to the surface of the substrate where the processing liquid remains. Forming a liquid film of a liquid mixture of the treatment liquid and the low surface tension liquid on the surface of the substrate, and a liquid film of the mixed liquid formed on the surface of the substrate. A substitution step of evaporating the treatment liquid and replacing the mixed liquid at least at an interface between the liquid film of the mixed liquid and the surface of the substrate with the low surface tension liquid; and replacing the low surface tension liquid with the substrate. From the surface of the substrate And a drying step of drying the surface, the drying step, towards a liquid film removal region forming step of forming a liquid film removal region on the liquid film of the liquid mixture, the liquid film removal region on the outer periphery of the substrate A liquid film removal region expanding step of expanding the substrate.

According to this method, the low surface tension liquid is supplied to the surface of the substrate where the processing liquid remains. As a result, the processing liquid and the low surface tension liquid are mixed, and a mixed liquid is formed on the surface of the substrate. Then, the processing liquid having a low boiling point contained in the mixed liquid evaporates, and as a result, the processing liquid on the surface of the substrate can be completely replaced with the low surface tension liquid.
Supplying a low surface tension liquid to form a liquid mixture and evaporating the processing liquid contained in the liquid mixture to leave only the low surface tension liquid, so increasing the rate of replacement of the processing liquid with the low surface tension liquid Can be. Thus, the processing liquid on the surface of the substrate can be completely replaced with the low surface tension liquid in a short time. Therefore, the surface of the substrate can be dried in a short time while suppressing collapse of the pattern.
Further, a liquid film of the mixed liquid is formed on the upper surface of the substrate held in the horizontal posture. A liquid film removal region is formed in the liquid film of the mixed liquid, and the liquid film removal region is enlarged until it covers the entire substrate. On the upper surface of the substrate, the liquid film is removed at the gas-solid interface of the liquid film of the mixed liquid while the liquid film removal region is enlarged. At the gas-solid interface, the processing liquid having a low boiling point is mainly evaporated, and as a result, the concentration of the low surface tension liquid increases. At this time, only the low surface tension liquid exists at the gas-solid interface, and in the vicinity of the liquid film interface of the mixed liquid, there is a concentration gradient such that the concentration of the low surface tension liquid decreases as the distance from the gas-solid interface increases. It is formed. That is, the treatment liquid can be completely replaced with the low surface tension liquid at the gas-solid interface. It is believed that when the liquid is completely removed from between the patterns, the surface tension of the liquid acts on the patterns. By completely substituting the liquid at the gas-solid interface with a low surface tension liquid, the surface tension acting on the pattern when the liquid is completely removed from the pattern can be suppressed to a low level, so that collapse of the pattern can be suppressed.

The invention according to claim 4, in parallel to the mixed liquid-liquid film forming step, or the substrate is a stationary state further comprises a paddle step of rotating the substrate at a paddle speed in time guinea line around, wherein Item 4. The substrate processing method according to Item 3 .
According to this method, since the paddle process is performed in parallel with the mixed liquid film forming process, the discharge of the low surface tension liquid from the substrate can be suppressed. Thereby, the amount of the low surface tension liquid used can be reduced.

The invention according to claim 5 is the substrate processing method according to claim 3 or 4 , wherein the liquid film removal region forming step includes a gas blowing step of blowing gas onto the upper surface of the substrate.
According to this method, by blowing gas onto the liquid film of the mixed liquid, the mixed liquid contained in the liquid film of the mixed liquid is partially blown off and removed. Thereby, the liquid film removal region can be easily formed.

Invention according to claim 6, wherein the liquid-film removal areas expanding large step includes a high-speed rotation step of rotating the substrate at a high speed than when the mixture liquid film forming step, one of the claims 3-5 The substrate processing method according to any one of the preceding claims.
According to this method, the liquid film removal region can be enlarged by the strong centrifugal force generated by rotating the substrate at high speed.

The invention according to claim 7 is the substrate processing method according to claim 5 , wherein the gas includes a high-temperature gas higher than room temperature.
According to this method, the evaporation of the processing liquid at the gas-solid interface of the liquid film of the mixed liquid can be promoted by supplying the high-temperature gas to the upper surface of the substrate. Thereby, the concentration gradient of the low surface tension liquid in the vicinity of the interface of the liquid film of the mixed liquid can be sharpened, and therefore, only the low surface tension liquid can be present at the gas-solid liquid interface.

The invention according to claim 8 is the substrate processing method according to any one of claims 1 to 7 , wherein the treatment liquid includes water, and the low surface tension liquid includes ethylene glycol.
According to this method, ethylene glycol (hereinafter, referred to as “EG”) is supplied to the surface of the substrate on which water remains. Thereby, the water and the EG are mixed, and a mixed liquid is formed on the surface of the substrate. Then, the water having a low boiling point contained in the mixture is mainly evaporated, and as a result, the water on the surface of the substrate can be completely replaced with EG.

  Since the mixed liquid is formed by the supply of the EG, and the water contained in the mixed liquid is evaporated to leave only the EG, the replacement speed of the water with the EG can be increased. Thus, the water on the surface of the substrate can be completely replaced with EG in a short time. Therefore, the surface of the substrate can be dried in a short time while suppressing collapse of the pattern. Thereby, the drying time can be shortened, and the amount of the organic solvent used can be reduced.

According to this method, EG is supplied to the surface of the substrate where water remains. Thereby, the water and the EG are mixed, and a mixed liquid is formed on the surface of the substrate. Then, water having a low boiling point contained in the mixed solution evaporates, and as a result, water on the surface of the substrate can be completely replaced with EG.
Since the mixed liquid is formed by the supply of the EG, and the water contained in the mixed liquid is evaporated to leave only the EG, the replacement speed of the water with the EG can be increased. Thus, the water on the surface of the substrate can be completely replaced with EG in a short time. Therefore, the surface of the substrate can be dried in a short time while suppressing collapse of the pattern.

According to a ninth aspect of the present invention, there is provided a substrate holding unit for holding a substrate horizontally and with its surface facing upward, and for supplying a processing liquid to the surface of the substrate. A low surface tension liquid supply unit for supplying a low surface tension liquid having a higher boiling point than the processing liquid and a lower surface tension than the processing liquid to the surface of the substrate, a heating unit for heating the liquid film that is formed on the surface of the substrate, the processing liquid supply unit, wherein by controlling the low surface tension liquid supply unit and the heating unit, the said processing liquid remaining Forming a liquid film of a mixed liquid of the treatment liquid and the low surface tension liquid on the surface of the substrate by supplying the low surface tension liquid to cover the surface of the substrate; Evaporating the treatment liquid from the liquid film of the mixed liquid formed on the surface of the substrate, and forming the mixed liquid at the interface between the liquid film of the mixed liquid and the surface of the substrate with the low surface tension. A control unit for performing a replacement step of replacing the liquid with a liquid, and a drying step of removing the low surface tension liquid from the surface of the substrate and drying the surface of the substrate, wherein the control unit performs the replacement step. A heating step of heating the liquid film of the mixed liquid after covering the surface of the substrate with the liquid film of the mixed liquid in order to evaporate the processing liquid contained in the liquid film of the mixed liquid. And a substrate processing apparatus.

According to this configuration, the same operation and effect as those described in the first aspect can be obtained .

According to a tenth aspect of the present invention, there is provided a substrate holding unit for holding a substrate horizontally and with its surface facing upward, and for supplying a processing liquid to the surface of the substrate. A processing liquid supply unit for supplying a low surface tension liquid having a higher boiling point than the processing liquid and a lower surface tension than the processing liquid to the surface of the substrate; and By controlling the processing liquid supply unit and the low surface tension liquid supply unit to supply the low surface tension liquid to the surface of the substrate on which the processing liquid remains, the processing liquid and the low surface tension liquid are supplied. Forming a liquid film of a liquid mixture with a liquid so as to cover the surface of the substrate; and evaporating the treatment liquid from the liquid film of the liquid mixture formed on the surface of the substrate. And said A replacement step of replacing the mixed liquid at the interface between the liquid film of the mixed liquid and the surface of the substrate with the low surface tension liquid, and removing the low surface tension liquid from the surface of the substrate, A control unit for performing a drying step of drying a surface, wherein the control unit performs a liquid film removal area forming step of forming a liquid film removal area in a liquid film of the mixed liquid in the drying step; A liquid film removal area expanding step of expanding a film removal area toward an outer periphery of the substrate.

  According to this configuration, the same operation and effect as the operation and effect described in relation to claim 3 can be obtained.

FIG. 1 is an illustrative plan view for explaining an internal layout of the substrate processing apparatus according to the first embodiment of the present invention. FIG. 2 is an illustrative sectional view for explaining a configuration example of a processing unit provided in the substrate processing apparatus. FIG. 3 is a block diagram for explaining an electrical configuration of a main part of the substrate processing apparatus. FIG. 4 is a flowchart for explaining an example of substrate processing by the substrate processing apparatus. 5A to 5C are schematic cross-sectional views for explaining the states of the mixed liquid forming step (S4 in FIG. 4), the mixed liquid heating step (S5 in FIG. 4), and the drying step (S6 in FIG. 4). is there. 6A to 6C are schematic sectional views showing the state of the surface of the substrate in the rinsing step (S3 in FIG. 4) and the mixed liquid forming step (S4 in FIG. 4). 6D to 6F are schematic sectional views showing the state of the surface of the substrate in the mixed liquid heating step (S5 in FIG. 4) and the drying step. FIG. 7 is an illustrative sectional view for explaining a configuration example of a processing unit provided in the substrate processing apparatus according to the second embodiment of the present invention. FIG. 8 is a block diagram for explaining an electrical configuration of a main part of the substrate processing apparatus. FIG. 9 is a flowchart for explaining an example of substrate processing by the substrate processing apparatus. 10A to 10C are schematic cross-sectional views for explaining the state of the mixed liquid forming step (S14 in FIG. 9) and the liquid film removal area forming step (S15 in FIG. 9). 10D to 10F are schematic cross-sectional views for explaining the state of the liquid film removal region expanding step (S16 in FIG. 9). FIG. 11 is an enlarged sectional view for explaining the inner peripheral portion of the liquid film of the water / EG mixed liquid. FIG. 12 is a schematic diagram for explaining a schematic configuration of the substrate processing apparatus according to the third embodiment of the present invention. FIG. 13 is an illustrative sectional view for explaining the principle of pattern collapse due to surface tension.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is an illustrative plan view for explaining an internal layout of a substrate processing apparatus according to one embodiment of the present invention. The substrate processing apparatus 1 is a single-wafer processing apparatus that processes a substrate W such as a silicon wafer one by one. In this embodiment, the substrate W is a disk-shaped substrate. The substrate processing apparatus 1 includes a plurality of processing units 2 for processing a substrate W with a processing liquid, a load port LP on which a carrier C containing a plurality of substrates W to be processed by the processing unit 2 is placed, and a load port LP. It includes transport robots IR and CR for transporting the substrate W between the LP and the processing unit 2, and a control unit 3 for controlling the substrate processing apparatus 1. The transfer robot IR transfers the substrate W between the carrier C and the transfer robot CR. The transfer robot CR transfers the substrate W between the transfer robot IR and the processing unit 2. The plurality of processing units 2 have, for example, a similar configuration.

FIG. 2 is an illustrative sectional view for explaining a configuration example of the processing unit 2.
The processing unit 2 holds a box-shaped processing chamber 4 and one substrate W in a horizontal position in the processing chamber 4 and rotates the substrate W about a vertical rotation axis A1 passing through the center of the substrate W. A spin chuck (substrate holding unit) 5, a chemical solution supply unit 6 for supplying a chemical solution to the upper surface of the substrate W held by the spin chuck 5, and a process A water supply unit (treatment liquid supply unit) 7 for supplying water as an example of an example, and a boiling point higher than water (treatment liquid) and higher than water (treatment liquid) on the upper surface (surface) of the substrate W An EG supply unit (low surface tension liquid supply unit) 8 that supplies ethylene glycol (hereinafter, referred to as “EG”) as an example of a low surface tension liquid having a low surface tension, and held by a spin chuck 5 The liquid film of the water / EG mixed liquid (hereinafter, referred to as “liquid film of the mixed liquid”) 50 (refer to FIG. 5B or the like) formed on the upper surface of the substrate W and opposed to the lower surface of the substrate W It includes a hot plate (heating unit) 9 for heating from below via W, and a cylindrical processing cup 10 surrounding the spin chuck 5.

The processing chamber 4 includes a box-shaped partition 11, an FFU (fan filter unit) 12 as a blower unit that sends clean air from above the partition 11 into the partition 11 (corresponding to the processing chamber 4), and a partition 11. And an exhaust device (not shown) for discharging the gas in the processing chamber 4 from the lower part of the apparatus.
The FFU 12 is disposed above the partition 11 and is attached to the ceiling of the partition 11. The FFU 12 sends clean air from the ceiling of the partition 11 into the processing chamber 4. The exhaust device is connected to the bottom of the processing cup 10 via an exhaust duct 13 connected to the inside of the processing cup 10, and sucks the inside of the processing cup 10 from the bottom of the processing cup 10. A downflow (downflow) is formed in the processing chamber 4 by the FFU 12 and the exhaust device.

  As the spin chuck 5, a sandwich type chuck that holds the substrate W horizontally while sandwiching the substrate W in the horizontal direction is employed. Specifically, the spin chuck 5 includes a cylindrical spin shaft 14 extending vertically, a disk-shaped spin base 15 attached to the upper end of the spin shaft 14 in a horizontal posture, and equidistantly arranged on the spin base 15. And a plurality of (at least three, for example, six) pinching pins 16 and a spin motor 17 connected to the spin shaft 14. The plurality of holding pins 16 are arranged at, for example, equal intervals on the circumference corresponding to the outer peripheral shape of the substrate W at the peripheral edge of the upper surface of the spin base 15. The plurality of holding pins 16 are upward holding pins (holding pins supported on the lower side), and each of the holding pins 16 is in contact with a peripheral portion of the substrate W to hold the substrate W, and The substrate W is also displaced between an open position radially outward of the substrate W. The substrate W is firmly held by the spin chuck 5 by holding each of the holding pins 16 in contact with the periphery of the substrate W and holding the substrate W. A drive mechanism (not shown) for displacing the pin 16 is connected to each pin 16. Further, instead of the holding pin 16, a downward holding pin (a holding pin whose upper side is supported) may be employed as the holding member.

The spin motor 17 is, for example, an electric motor. The substrate W held by the holding pins 16 rotates integrally with the spin base 15 around a vertical rotation axis A1 passing through the center of the substrate W by the rotation driving force from the spin motor 17 being transmitted to the spin shaft 14. Let me do.
The hot plate 9 is formed, for example, in a disk shape having a horizontal flat surface, and has an outer diameter equal to the outer diameter of the substrate W. The hot plate 9 has a circular upper surface facing the lower surface (back surface) of the substrate W held by the spin chuck 5. The hot plate 9 is disposed in a horizontal posture between the upper surface of the spin base 15 and the lower surface of the substrate W held by the spin chuck 5. The hot plate 9 is formed using ceramic or silicon carbide (SiC), and has a heater 18 embedded therein. The heating of the heater 18 warms the entire hot plate 9 and the hot plate 9 functions to heat the substrate W. In the entire area of the upper surface of the hot plate 9, the amount of heat generated per unit area of the upper surface when the heater 18 is on is set to be uniform. The hot plate 9 is supported by a support rod 20 that passes through a through hole 19 vertically passing through the spin base 15 and the spin shaft 14 in the vertical direction (the thickness direction of the spin base 15) along the rotation axis A1. The lower end of the support rod 20 is fixed to a peripheral member below the spin chuck 5. Since the hot plate 9 is not connected to the spin motor 17, the hot plate 9 does not rotate but remains stationary (non-rotating state) even while the substrate W is rotating.

  A heater elevating unit 21 for elevating and lowering the hot plate 9 is connected to the support rod 20. The hot plate 9 is moved up and down by the heater elevating unit 21 while maintaining the horizontal posture. The heater elevating unit 21 is constituted by, for example, a ball screw or a motor. By driving the heater elevating unit 21, the hot plate 9 has a minute position at a lower position (see FIG. 5A and the like) separated from the lower surface of the substrate W held by the spin chuck 5 and a lower surface of the substrate W held by the spin chuck 5. It is raised and lowered between upper positions (see FIG. 5B) approaching at intervals.

  With the upper surface of the hot plate 9 at the upper position, the distance between the lower surface of the substrate W and the upper surface of the hot plate 9 is set to, for example, about 0.3 mm, and the upper surface of the hot plate 9 is at the lower position. In this state, the distance between the lower surface of the substrate W and the upper surface of the hot plate 9 is set to, for example, about 10 mm. Thus, the distance between the hot plate 9 and the substrate W can be changed.

  The chemical solution supply unit 6 includes a chemical solution nozzle 23. The chemical liquid nozzle 23 is, for example, a straight nozzle that discharges a liquid in a continuous flow state, and is fixedly disposed above the spin chuck 5 with its discharge port facing the center of the upper surface of the substrate W. The chemical liquid nozzle 23 is connected to a chemical liquid pipe 24 to which a chemical liquid from a chemical liquid supply source is supplied. A chemical liquid valve 25 for switching supply / supply stop of the chemical liquid from the chemical liquid nozzle 23 is provided at an intermediate portion of the chemical liquid pipe 24. When the chemical liquid valve 25 is opened, a continuous flow of the chemical liquid supplied from the chemical liquid pipe 24 to the chemical liquid nozzle 23 is discharged from a discharge port set at the lower end of the chemical liquid nozzle 23. When the chemical liquid valve 25 is closed, the supply of the chemical liquid from the chemical liquid pipe 24 to the chemical liquid nozzle 23 is stopped.

Specific examples of the chemical liquid include an etching liquid and a cleaning liquid. More specifically, the chemical solution is hydrofluoric acid, SC1 (a mixed solution of aqueous ammonia and hydrogen peroxide), SC2 (a mixed solution of aqueous hydrogen peroxide), ammonium fluoride, and buffered hydrofluoric acid (a mixture of hydrofluoric acid and ammonium fluoride). Liquid mixture).
The water supply unit 7 includes a water nozzle 26. The water nozzle 26 is, for example, a straight nozzle that discharges a liquid in a continuous flow state, and is fixedly disposed above the spin chuck 5 with its discharge port facing the center of the upper surface of the substrate W. The water nozzle 27 is connected to a water pipe 27 to which water from a water supply source is supplied. A water valve 28 for switching supply / stop of water supply from the water nozzle 26 is provided at an intermediate portion of the water pipe 27. When the water valve 28 is opened, the continuous flow of water supplied from the water pipe 27 to the water nozzle 26 is discharged from a discharge port set at the lower end of the water nozzle 26. When the water valve 28 is closed, the supply of water from the water pipe 27 to the water nozzle 26 is stopped. The water is, for example, deionized water (DIW), but is not limited to DIW, and may be any of carbonated water, electrolytic ionic hydrogen water, ozone water, and hydrochloric acid water having a diluted concentration (for example, about 10 ppm to 100 ppm). Good. The boiling point and surface tension of water (DIW) are 100 ° C. and 72.75, respectively, at room temperature.

  The chemical liquid nozzle 23 and the water nozzle 26 do not need to be fixedly arranged with respect to the spin chuck 5, respectively. For example, the chemical nozzle 23 and the water nozzle 26 are attached to an arm that can swing in a horizontal plane above the spin chuck 5. A so-called scan nozzle configuration in which the landing position of the processing liquid (chemical solution or water) on the upper surface of the substrate W is scanned by the swing of the arm, may be employed.

  The EG supply unit 8 is configured to move the EG nozzle 29 for discharging EG, the first nozzle arm 30 having the EG nozzle 29 attached to a distal end thereof, and the first nozzle arm 30 to move the EG nozzle 29. And a first nozzle moving unit 31 that moves the nozzle. The EG nozzle 29 is, for example, a straight nozzle that discharges EG in a continuous flow state, and is attached to a first nozzle arm 30 that extends in the horizontal direction with its discharge port directed downward, for example.

  The EG supply unit 8 is connected to the EG nozzle 29, and supplies an EG from the EG supply source to the EG nozzle 29. An EG pipe 32 and an EG valve for switching supply / stop of the EG from the EG nozzle 29. 33, and a first flow rate adjusting valve 34 for adjusting the opening degree of the EG pipe 32 to adjust the flow rate of EG discharged from the EG nozzle 29. The first flow control valve 34 includes a valve body (not shown) having a valve seat provided therein, a valve body for opening and closing the valve seat, and an actuator for moving the valve body between an open position and a closed position. (Not shown). The same applies to other flow control valves. The boiling point and surface tension of EG are 197.5 ° C. and 47.3 at room temperature, respectively. That is, EG is a liquid having a higher boiling point than water and a lower surface tension than water.

  As shown in FIG. 2, the processing cup 10 is disposed outside (in a direction away from the rotation axis A1) the substrate W held by the spin chuck 5. The processing cup 10 surrounds the spin base 15. 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 10 a of the processing cup 10 opened upward is disposed above the spin base 15. Therefore, a processing liquid such as a chemical solution or water discharged around the substrate W is received by the processing cup 10. Then, the processing liquid received by the processing cup 10 is sent to a not-shown recovery device or waste liquid device.

FIG. 3 is a block diagram for explaining an electrical configuration of a main part of the substrate processing apparatus 1.
The control unit 3 controls operations of the spin motor 17, the heater elevating unit 21, the first nozzle moving unit 31, and the like according to a predetermined program. Further, the control unit 3 controls opening and closing operations of the chemical liquid valve 25, the water valve 28, the EG valve 33, the first flow control valve 34, and the like. Further, the control unit 3 controls on / off of the heater 18.

  FIG. 4 is a flowchart for explaining an example of substrate processing by the substrate processing apparatus 1. 5A to 5C are schematic cross-sectional views for explaining the states of the mixed liquid forming step (S4 in FIG. 4), the mixed liquid heating step (S5 in FIG. 4), and the drying step (S6 in FIG. 4). is there. 6A to 6F show the substrate W in the rinsing step (S3 in FIG. 4), the mixed liquid forming step (S4 in FIG. 4), the mixed liquid heating step (S5 in FIG. 4), and the drying step (S6 in FIG. 4). It is an illustrative sectional view showing the state of the surface. The substrate processing will be described with reference to FIGS.

  The unprocessed substrate W is carried into the processing unit 2 from the carrier C by the transfer robots IR and CR, and is carried into the processing chamber 4, where the substrate W has its surface (the surface to be processed; the pattern forming surface in this embodiment). The wafer W is transferred to the spin chuck 5 while being directed upward, and the substrate W is held by the spin chuck 5 (S1: substrate loading step (substrate holding step)). Prior to loading of the substrate W, the EG nozzle 29 is retracted to a home position set on the side of the spin chuck 5. Further, the hot plate 9 is arranged at a lower position separated from the lower surface of the substrate W. At this time, the heater 18 is off.

After the transfer robot CR has retreated outside the processing unit 2, the control unit 3 controls the spin motor 17 to start rotating the substrate W and accelerate the substrate W to a predetermined liquid processing rotation speed (for example, about 800 rpm).
Further, the control unit 3 turns on the heater 18. As a result, the heater 18 generates heat, and the upper surface temperature of the hot plate 9 is raised to a predetermined high temperature. Although the surface of the hot plate 9 becomes hot when the heater 18 is turned on, the substrate W is hardly heated by the heat from the hot plate 9 because the hot plate 9 is located at the lower position.

  Next, the control unit 3 executes a chemical solution process (Step S2). Specifically, after the rotation speed of the substrate W reaches the liquid processing speed, the control unit 3 opens the chemical liquid valve 25. Thereby, the chemical solution is supplied from the chemical solution nozzle 23 toward the upper surface of the substrate W in the rotating state. The supplied chemical solution spreads over the entire surface of the substrate W by centrifugal force, and the substrate W is subjected to a chemical solution treatment using the chemical solution. When a predetermined period elapses from the start of the discharge of the chemical, the control unit 3 closes the chemical valve 25 and stops the discharge of the chemical from the chemical nozzle 23.

  Next, the control unit 3 executes a rinsing step (Step S3). The rinsing step (S3) is a step of replacing the chemical solution on the substrate W with water to remove the chemical solution from the substrate W. Specifically, the control unit 3 opens the water valve 28. Thereby, water is supplied from the water nozzle 26 toward the upper surface of the substrate W in a rotating state. The supplied water spreads over the entire surface of the substrate W by centrifugal force. The chemicals attached to the substrate W are washed away by the water.

  When a predetermined period elapses from the start of the supply of water, the control unit 3 controls the spin motor 17 to change the rotation speed of the substrate W from the liquid processing speed while the entire upper surface of the substrate W is covered with water. The paddle speed is gradually reduced to a paddle speed (zero or a low rotation speed of about 40 rpm or less, for example, about 10 rpm). Thereafter, the rotation speed of the substrate W is maintained at the paddle speed. Thus, a liquid film of water covering the entire upper surface of the substrate W is supported in a paddle shape on the upper surface of the substrate W. In this state, the centrifugal force acting on the liquid film of water on the upper surface of the substrate W is smaller than the surface tension acting between water and the upper surface of the substrate W, or the centrifugal force and the surface tension are different. They are almost antagonistic. Due to the deceleration of the substrate W, the centrifugal force acting on the water on the substrate W weakens, and the amount of water discharged from the substrate W decreases. Thus, a paddle-shaped water liquid film 45 is formed on the upper surface of the substrate W as shown in FIG. 6A. Thereafter, the rotation speed of the substrate W is maintained at the paddle speed. After the formation of the liquid film 45 of water, the supply of water to the substrate W is stopped. However, after the formation of the paddle-shaped liquid film of water, the supply of water to the substrate W may be continued.

Next, a mixed liquid forming step (Step S4 in FIG. 4) is performed.
Specifically, when a predetermined period elapses after the substrate W is decelerated, the control unit 3 controls the first nozzle moving unit 31 to move the EG nozzle 29 from the home position to the processing position above the substrate W. Let it. After that, the control unit 3 opens the EG valve 33 and discharges EG from the EG nozzle 29 toward the upper surface of the substrate W. Further, the control unit 3 moves the EG supply position with respect to the upper surface of the substrate W between the central part and the peripheral part. Thus, the water supply position scans the entire upper surface of the substrate W, and EG is directly applied to the entire upper surface of the substrate W. For a while after the start of the discharge of the EG, the EG does not sufficiently spread inside the liquid film 45. As a result, as shown in FIG. 6B, EG stays in the surface layer of liquid film 45 and water stays in the base layer of liquid film 45. In this state, a mixed liquid of water and EG (hereinafter, referred to as “water / EG mixed liquid”) is formed only in the liquid film 45 at an intermediate portion between the surface layer portion and the base layer portion. Thereafter, as time passes, the EG spreads over the entire area of the liquid film 45, and the entire area of the liquid film 45 of water is replaced by the water / EG mixture. That is, the liquid film 50 of the mixed liquid is formed on the upper surface of the substrate W (see FIGS. 5A and 6C).

Next, the control unit 3 executes a mixed liquid heating step (Step S5 in FIG. 4).
Specifically, the control unit 3 controls the heater elevating unit 21 to raise the hot plate 9 from a lower position (see FIG. 5A and the like) to an upper position as shown in FIG. 5B. By arranging the hot plate 9 at the upper position, the substrate W is heated by heat radiation from the upper surface of the hot plate 9 at the upper position. Further, since the substrate W is heated to a high temperature, the liquid film 50 of the mixed liquid on the upper surface of the substrate W is also heated to a high temperature substantially equal to the temperature of the substrate W. The heating temperature of the liquid mixture 50 with respect to the liquid film 50 is set to a predetermined high temperature (for example, about 150 ° C.) higher than the boiling point of water and lower than the boiling point of EG.

  By heating the liquid film 50 of the mixed liquid, as shown in FIG. 6D, the water contained in the liquid film 50 of the mixed liquid boils, and the water evaporates from the liquid film 50 of the mixed liquid. As a result, water is completely removed from the liquid film 50 of the mixed liquid, and the liquid film contains only EG as shown in FIG. 6E. That is, the EG liquid film 51 is formed on the upper surface of the substrate W. Thereby, the water on the upper surface of the substrate W can be completely replaced with EG.

After the elapse of a predetermined period from the rise of the hot plate 9, the control unit 3 controls the heater elevating unit 21 to move the position of the hot plate 9 to the upper position (FIG. 5B), as shown in FIG. 5C. Ref.) To lower position. Thus, the heating of the substrate W by the hot plate 9 ends.
Next, the control unit 3 controls the spin motor 17 to shake off the rotation speed of the substrate W to a drying speed (for example, 1500 rpm) as shown in FIG. 5C. Thereby, the liquid film 51 of the EG on the upper surface of the substrate W is shaken off, and the substrate W is dried (spin drying; S6 in FIG. 4: drying step). In the drying step (S6), as shown in FIG. 6F, EG is removed from between the structures P1 of the pattern P. Since EG has a lower surface tension than water, pattern collapse in the drying step (S6) can be suppressed.

  When a predetermined period has elapsed from the start of the drying step (S6), the control unit 3 controls the spin motor 214 to stop the rotation of the spin chuck 5. Further, the control unit 3 turns off the heater 18. Thereafter, the transport robot CR enters the processing unit 2 and unloads the processed substrate W out of the processing unit 2 (Step S7 in FIG. 4). The substrate W is transferred from the transfer robot CR to the transfer robot IR, and is stored in the carrier C by the transfer robot IR.

As described above, according to the first embodiment, EG is supplied to the liquid film 45 of the water on the substrate W. Thereby, the water and the EG are mixed, and a liquid film 50 of the mixed liquid is formed on the upper surface of the substrate W. When the liquid film 50 of the mixed liquid is heated, the water contained in the liquid film 50 of the mixed liquid evaporates. As a result, the water in the liquid film 50 of the mixed liquid can be completely replaced with EG.
The liquid film 50 of the mixed liquid is formed by the supply of the EG, and the water contained in the liquid film 50 of the mixed liquid is evaporated to leave only the EG, so that the replacement speed of the water with the EG can be increased. Thereby, the water on the upper surface of the substrate W can be completely replaced with EG in a short time. Therefore, the upper surface of the substrate W can be dried in a short time while suppressing the collapse of the pattern P. Thereby, the drying time of the substrate W can be shortened, and the amount of EG used can be reduced.

  In the mixed liquid heating step (S5 in FIG. 4), the heating temperature of the mixed liquid to the liquid film 50 is set to a predetermined high temperature (for example, about 150 ° C.) higher than the boiling point of water and lower than the boiling point of EG. ing. Therefore, although EG in the water / EG mixture hardly evaporates, evaporation of water in the water / EG mixture is accelerated. That is, only water in the liquid film 50 of the mixed liquid can be efficiently evaporated. This makes it possible to achieve complete replacement with a low surface tension liquid in a shorter time.

Further, since the heating temperature of the liquid mixture 50 with respect to the liquid film 50 is lower than the boiling point of the EG, the liquid film of the EG having a predetermined thickness is held on the upper surface of the substrate W after the liquid mixture heating step (S5 in FIG. 4). it can.
Further, a liquid film 45 of a paddle-like water is formed on the upper surface of the substrate W, and EG is supplied to the liquid film 45 of the water to form a liquid film 50 of the mixed liquid on the upper surface of the substrate W. Emission of EG from W can be suppressed. As a result, the amount of EG used can be further reduced.

FIG. 7 is an illustrative sectional view for explaining a configuration example of a processing unit 202 provided in a substrate processing apparatus 201 according to the second embodiment of the present invention.
In the second embodiment, portions corresponding to the respective portions shown in the above-described first embodiment are denoted by the same reference numerals as those in FIGS. 1 to 6F, and description thereof is omitted.
The main difference between the processing unit 202 and the processing unit 2 according to the first embodiment is that the processing unit 202 includes a spin chuck (substrate holding unit) 205 instead of the spin chuck 5. That is, the processing unit 2 does not include the hot plate 9.

The main difference between the processing unit 202 and the processing unit 2 according to the first embodiment is that a gas unit 237 for supplying gas to the upper surface of the substrate W held by the spin chuck 205 is further provided. It is a point that includes.
As the spin chuck 205, a sandwich type chuck that horizontally holds the substrate W and horizontally holds the substrate W is employed. Specifically, the spin chuck 205 includes a spin motor 214, a spin shaft 215 integrated with a drive shaft of the spin motor 214, and a disk-shaped spin base mounted substantially horizontally on an upper end of the spin shaft 215. 216.

  The spin base 216 includes a horizontal circular upper surface 216a having an outer diameter larger than the outer diameter of the substrate W. On the upper surface 216a, a plurality (three or more, for example, six) of sandwiching members 217 are arranged at a peripheral portion thereof. The plurality of sandwiching members 217 are arranged at, for example, equal intervals on the circumference corresponding to the outer peripheral shape of the substrate W at the peripheral edge of the upper surface of the spin base 216.

  The gas unit 237 includes a gas nozzle 235 that discharges a nitrogen gas as an example of an inert gas toward the upper surface of the substrate W, a second nozzle arm 236 having the gas nozzle 235 attached to the tip, and a second nozzle arm 236. A second nozzle moving unit 238 for moving the gas nozzle 235 by moving the nozzle arm 236. The gas nozzle 235 is attached to a second nozzle arm 236 that extends in the horizontal direction with its discharge port directed downward, for example.

  The gas nozzle 235 is connected to a gas pipe 239 to which a high-temperature (higher than normal temperature, for example, 30 to 300 ° C.) inert gas is supplied from an inert gas supply source. In the middle of the gas pipe 239, a gas valve 240 for switching supply / stop of the inert gas from the gas nozzle 235 and an opening degree of the gas pipe 239 are adjusted so that the gas discharged from the gas nozzle 235 can be controlled. A second flow control valve 241 for adjusting the flow rate of the active gas is interposed. When the gas valve 240 is opened, the inert gas supplied from the gas pipe 239 to the gas nozzle 235 is discharged from the discharge port. When the gas valve 240 is closed, the supply of the inert gas from the gas pipe 239 to the gas nozzle 235 is stopped. The inert gas is not limited to nitrogen gas, but may be CDA (clean air with low humidity).

FIG. 8 is a block diagram for describing an electrical configuration of a main part of the substrate processing apparatus 201.
The control unit 3 controls the operations of the spin motor 214, the first and second nozzle moving units 31, 238, and the like according to a predetermined program. Further, the control unit 3 controls opening / closing operations of the chemical liquid valve 25, the water valve 28, the EG valve 33, the gas valve 240, the first and second flow control valves 34, 241 and the like.

  FIG. 9 is a flowchart for explaining an example of substrate processing by the substrate processing apparatus 201. 10A to 10F are illustrations for explaining the states of a mixed liquid forming step (S14 in FIG. 9), a liquid film removing area forming step (S15 in FIG. 9), and a liquid film removing area enlarging step (S16 in FIG. 9). FIG. The substrate processing by the substrate processing apparatus 201 will be described with reference to FIGS.

  The unprocessed substrate W is carried into the processing chamber 204 by the transfer robots IR and CR, and the spin chuck 205 is placed in a state where the surface of the substrate W (the surface to be processed; the pattern forming surface in this embodiment) faces upward. The substrate W is held by the spin chuck 205 (S11: substrate loading step (substrate holding step)). Prior to loading of the substrate W, the EG nozzle 29 and the gas nozzle 235 are retracted to a home position set on the side of the spin chuck 205.

  After the transfer robot CR has retreated outside the processing unit 202, the control unit 3 starts rotating the substrate W, and sequentially performs the chemical solution process (Step S12), the rinsing process (Step S13), and the mixed solution forming process (Step S14). Execute. The chemical solution step (S12), the rinsing step (S13), and the mixed liquid forming step (S14) include the chemical liquid step (S2), the rinsing step (S3), and the mixed liquid forming step (S4) according to the first embodiment, respectively. Since these steps are the same, their description will be omitted.

In the mixed liquid forming step (S14), a liquid film 50 of the mixed liquid is formed on the upper surface of the substrate W (see FIGS. 10A and 6C). Prior to the end of the mixed liquid forming step (S14), the control unit 3 controls the second nozzle moving unit 238 to move the gas nozzle 235 to the home position on the side of the spin chuck 205 as shown in FIG. 10B. From above the substrate W.
When a predetermined period elapses from the start of the mixed liquid forming step (S14), the control unit 3 executes a drying step. In the drying step, a liquid film removal area forming step (S15), a liquid film removal area enlargement step (S16), and an acceleration step (S17) are performed in this order. The liquid film removing area forming step (S15) is a step of forming a liquid film removing area 55 from which the mixed liquid has been removed at the center of the liquid film 50 of the mixed liquid. The liquid film removal area expanding step (S16) is a step of expanding the liquid film removal area 55 to the entire upper surface of the substrate W.

  In the liquid film removal region forming step (S15), the control unit 3 opens the gas valve 240 to discharge an inert gas from the gas nozzle 235 toward the center of the upper surface of the substrate W (gas blowing step), and By controlling the motor 214, the substrate W is accelerated to a predetermined drilling speed (for example, about 50 rpm) (high-speed rotation process). When the inert gas is blown to the center of the liquid film 50 of the mixed liquid on the upper surface of the substrate W, the water / EG mixed liquid at the center of the liquid film 50 of the mixed liquid is blown by the blowing pressure (gas pressure). It is blown off from the center of the upper surface of the substrate W and removed. Further, when the rotation speed of the substrate W reaches the above-described punching speed (for example, about 50 rpm), a relatively strong centrifugal force acts on the liquid film 50 of the mixed liquid on the substrate W. As a result, a circular liquid film removal region 55 is formed at the center of the upper surface of the substrate W, as shown in FIG. 10C. The drilling speed was about 50 rpm, but a rotation speed higher than that may be used. After the liquid film removal area forming step (S15), a liquid film removal area enlarging step (S16) is performed.

  In the liquid film removal area expanding step (S16), the control unit 3 controls the spin motor 214 to increase the rotation speed of the substrate W to a predetermined first drying speed (for example, 1000 rpm). As the rotation speed of the substrate W increases, the liquid film removal area 55 expands as shown in FIGS. 10D and 10E. As the liquid film removal region 55 expands, the gas-solid liquid interface 60 of the liquid film 50 of the mixed liquid with the liquid film removal region 55 and the upper surface of the substrate W moves outward in the radial direction of the substrate W. Then, as shown in FIG. 10F, the liquid film removal region 55 is expanded to the entire region of the substrate W, so that the liquid film 50 of the mixed liquid is entirely discharged out of the substrate W.

After the liquid film removal area 55 has been expanded to the entire upper surface of the substrate W, the liquid film removal area expansion step ends. With the end of the liquid film removal area enlarging step, the control unit 3 closes the gas valve 240 and stops the discharge of the inert gas from the gas nozzle 235.
Next, the control unit 3 executes an acceleration step (S17). Specifically, the control unit 3 increases the rotation speed of the substrate W to about 1500 rpm. Thereby, further drying on the upper surface of the substrate W is achieved.

  When a predetermined period has elapsed from the start of the acceleration step (S17), the control unit 3 controls the spin motor 214 to stop the rotation of the spin chuck 205. Thereafter, the transport robot CR enters the processing unit 202 and unloads the processed substrate W out of the processing unit 202 (Step S18). The substrate W is transferred from the transfer robot CR to the transfer robot IR, and is stored in the carrier C by the transfer robot IR.

FIG. 11 is an enlarged sectional view for explaining the inner peripheral portion of the liquid film 50 of the mixed liquid.
After the formation of the liquid film removal region 55, water having a low boiling point is mainly evaporated at the gas-liquid interface 60, and as a result, the EG concentration increases. At this time, a concentration gradient is formed in the inner peripheral portion 70 of the liquid film of the liquid mixture such that the concentration of EG decreases as the distance from the gas-solid interface 60 increases. In this embodiment, the EG concentration of the liquid film 50 of the mixed liquid is determined so that only EG exists at the gas-liquid interface 60 (that is, the supply amount of EG in the mixed liquid forming step (S14) is determined). Is). In this case, water can be completely replaced with EG at the gas-solid interface 60.

As described above, according to this embodiment, EG is supplied to the liquid film 45 of the water on the substrate W. Thereby, the water and the EG are mixed, and a liquid film 50 of the mixed liquid is formed on the upper surface of the substrate W.
Then, a liquid film removal region 55 is formed in the liquid film 50 of the mixed liquid, and the liquid film removal region 55 is further enlarged until it covers the entire substrate W. On the upper surface of the substrate W, the liquid film removal region 55 expands while the water / EG mixed liquid evaporates at the gas-solid liquid interface 60 of the liquid film 50 of the mixed liquid. At the gas-solid interface 60, water having a low boiling point is mainly evaporated, and as a result, the concentration of EG increases. At this time, only EG exists at the gas-solid interface 60, and a concentration gradient is formed in the inner peripheral portion 70 of the liquid film of the mixed liquid such that the concentration of EG decreases as the distance from the gas-solid interface 60 increases. . That is, water can be completely replaced with EG at the gas-solid interface 60. It is considered that when the liquid is completely removed from between the patterns P, the surface tension of the liquid acts on the pattern P. By completely replacing the liquid with the EG at the gas-solid interface 60, the surface tension acting on the pattern P when the liquid is completely removed from the pattern P can be suppressed to a low level.

  Further, since the liquid film 50 of the mixed liquid is formed by the supply of the EG, and the water contained in the liquid film 50 of the mixed liquid is evaporated to leave only the EG, the replacement speed of the water with the EG can be increased. it can. Thereby, the water on the upper surface of the substrate W can be completely replaced with EG in a short time. Therefore, the upper surface of the substrate W can be dried in a short time while suppressing the collapse of the pattern P. Thereby, the drying time of the substrate W can be shortened, and the amount of EG used can be reduced.

Further, by supplying a high-temperature inert gas to the upper surface of the substrate W, evaporation of water at the gas-solid interface 60 of the liquid film 50 of the mixed liquid can be promoted. Thereby, EG can be completely replaced at the gas-solid interface 60 of the liquid film 50 of the mixed liquid.
Further, a liquid film 45 of a paddle-like water is formed on the upper surface of the substrate W, and EG is supplied to the liquid film 45 of the water to form a liquid film 50 of the mixed liquid on the upper surface of the substrate W. Emission of EG from W can be suppressed. As a result, the amount of EG used can be further reduced.

The present invention can also be applied to a batch type substrate processing apparatus.
FIG. 12 is a schematic diagram for explaining a schematic configuration of a substrate processing apparatus 301 according to the third embodiment of the present invention.
The substrate processing apparatus 301 is a batch type substrate processing apparatus that processes a plurality of substrates W at a time. The substrate processing apparatus 301 includes a chemical solution storage tank 302 for storing a chemical solution, a water storage tank 303 for storing water, an EG storage tank 304 for storing an EG mixture, and EG stored in the EG storage tank 304. A lifter 305 for immersing W and a lifter elevating unit 306 for raising and lowering the lifter 305 are included. The lifter 305 supports each of the plurality of substrates W in a vertical posture. The lifter elevating unit 306 includes a processing position (a position indicated by a solid line in FIG. 12) in which the substrate W held by the lifter 305 is located in the EG storage tank 304 and a EG storage tank in which the substrate W held by the lifter 305 is positioned. The lifter 305 is moved up and down between a retracted position (a position shown by a two-dot chain line in FIG. 12) located above the 304.

  The EG storage tank 304 is provided with a heater 307 that is immersed in the stored EG and heats the EG to adjust the temperature. As the heater 307, a sheath heater can be exemplified. Further, the EG storage tank 304 is further provided with a thermometer (not shown) for measuring the liquid temperature of the EG, a liquid amount sensor (not shown) for monitoring the liquid amount in the EG storage tank 304, and the like. The liquid temperature of the EG stored in the EG storage tank 304 is adjusted to, for example, about 150 ° C.

  In a series of processes in the substrate processing apparatus 301, the plurality of substrates W carried into the processing unit of the substrate processing apparatus 301 are immersed in the chemical stored in the chemical storage tank 302. Thereby, a chemical solution process (cleaning process or etching process) is performed on each substrate W. When a predetermined period elapses from the start of immersion in the chemical, a plurality of substrates W are lifted from the chemical storage tank 302 and moved to the water storage tank 303. Next, the plurality of substrates W are immersed in the water stored in the water storage tank 303. Thereby, the rinsing process is performed on the substrate W. When a predetermined period has elapsed from the start of immersion in water, the substrate W is lifted from the water storage tank 303 and moved to the EG storage tank 304.

  Then, the lifter elevating unit 306 is controlled to move the lifter 305 from the retracted position to the processing position, so that the plurality of substrates W held by the lifter 305 are immersed in the EG. By this immersion, EG is supplied to the water remaining on the surface of the substrate W (the surface to be processed; in this embodiment, the pattern forming surface). Thereby, the water and the EG are mixed, and the water / EG mixed liquid is supplied to the upper surface of the substrate W.

  Since the temperature of the EG stored in the EG storage tank 304 is adjusted to about 150 ° C., the water / EG mixed liquid on the upper surface of the substrate W is heated (a mixed liquid heating step). As a result, the water contained in the water / EG mixture supplied to the upper surface of the substrate W boils, and the water evaporates from the water / EG mixture. The liquid on the surface of the substrate W contains only EG. Thereby, the water on the surface of the substrate W can be completely replaced with EG. Therefore, pattern collapse on the surface of the substrate W when the substrate W is pulled up from the EG can be suppressed.

The three embodiments of the present invention have been described above, but the present invention can be embodied in other forms.
Further, in the first embodiment, the configuration in which the heating / non-heating of the substrate W is switched by moving the hot plate 9 up and down has been described as an example, but the substrate W is turned on / off by the heater 18 built in the hot plate 9. A configuration for switching between heating and non-heating may be adopted.

  In the first embodiment, the configuration in which the liquid film 50 of the mixed liquid is heated from below via the substrate W has been described. Instead of this configuration, the liquid film 50 of the mixed liquid is heated from above the substrate W by the heater. May be adopted. In this case, when the heater has a smaller diameter than the substrate W, it is desirable that the heater irradiates the liquid film 50 of the mixed liquid while moving along the upper surface of the substrate W. When the heater has a diameter equal to or larger than that of the substrate W, the heater may be configured to irradiate the liquid film 50 of the mixed liquid in a state where the heater is opposed to the substrate W.

In the first and third embodiments, the heating temperature of the liquid mixture 50 with respect to the liquid film 50 and the liquid temperature of the EG stored in the EG storage tank 304 are set to about 150 ° C., respectively. It is possible to set a predetermined high temperature in a range higher than the boiling point of water and lower than the boiling point of EG.
In the first and second embodiments, the paddle-shaped liquid film 45 of water is formed on the upper surface of the substrate W, and EG is supplied to the liquid film 45 of the paddle to form the liquid film 50 of the mixed liquid. It was formed on the upper surface of the substrate W. However, the liquid film 50 of the mixed liquid may be formed by supplying EG to the upper surface of the substrate W rotating at a speed higher than the paddle speed (for example, the liquid processing speed).

  In addition, the liquid film 50 of the mixed liquid was formed on the upper surface of the substrate W by supplying EG to the liquid film 45 of the water formed on the upper surface of the substrate W. However, the liquid film of water was formed on the upper surface of the substrate W. State (a state in which water droplets exist on the upper surface of the substrate W, or a state in which no liquid film or droplets exist on the surface of the substrate but water has entered the pattern P on the surface of the substrate) EG may be supplied to the upper surface of the substrate W in the (state) to form the liquid film 50 of the mixed liquid.

In the second embodiment, the configuration in which the liquid film 50 of the paddle-shaped mixed liquid is formed on the upper surface of the substrate W and the liquid film removal region 55 is provided in the liquid film 50 of the paddle-shaped mixed liquid has been described. The liquid film 50 of the mixed liquid is not limited to the paddle shape, and the liquid film removal region 55 may be provided in a liquid film of water rotated at a speed higher than the paddle speed.
In the second embodiment, the case where an inert gas is used as the gas supplied to the upper surface of the substrate W has been described as an example. However, as the gas, an organic solvent having a lower surface tension than water (for example, IPA) (Isopropyl alcohol) or HFE (hydrofluoroether) vapor may be employed.

In the second embodiment, a mixed gas of an inert gas and a vapor of an organic solvent can be used as the gas supplied to the upper surface of the substrate W.
Further, in the second embodiment, a description has been given assuming that a high-temperature gas is used as the gas supplied to the upper surface of the substrate W. However, a normal-temperature gas may be used.
In the second embodiment, the liquid film removal region 55 is formed in the liquid film 50 of the mixed liquid by both increasing the rotation speed of the substrate W and supplying gas to the upper surface of the substrate W. However, the liquid film removal region 55 may be formed only by blowing gas onto the upper surface of the substrate W without increasing the rotation speed of the substrate W, or only by increasing the rotation speed of the substrate W. May form the liquid film removal region 55.

  Further, in the second embodiment, the rotation of the substrate W is accelerated to the first drying speed in order to expand the liquid film removal region 55 to the entire region of the substrate W in the liquid film removal region expanding step. Instead of, or in conjunction with, the acceleration of the rotation of the substrate W, the liquid film removal region 55 may be expanded by increasing the flow rate of blowing the gas onto the upper surface of the substrate W.

  Further, the gas unit 237 may include a facing member facing the upper surface (front surface) of the substrate W held by the spin chuck 205 so as to be able to move integrally with the gas nozzle. This opposing member may have an opposing surface that closely approaches the surface of the substrate W with the discharge port of the gas nozzle 235 approaching the upper surface of the substrate W. In this case, a horizontal annular discharge port may be separately provided in the gas nozzle 235 having a downward discharge port.

When gas is not supplied to the upper surface of the substrate W, the gas unit 237 can be omitted.
Further, in the drying step of the second embodiment, the acceleration step (S16) may be omitted.
Further, in each of the above-described embodiments, a combination of water and EG is exemplified as a combination of the treatment liquid and the low surface tension liquid having a higher boiling point than the treatment liquid and a lower surface tension than the treatment liquid. However, as other combinations, a combination of IPA and HFE or a combination of water and PGMEA (propyleneglycol monomethyl ether acetate) can also be exemplified.

Further, in each of the above-described embodiments, the case where the substrate processing apparatuses 1, 201, 301 are apparatuses for processing the disk-shaped substrate W has been described. An apparatus for processing a polygonal substrate such as a glass substrate may be used.
In addition, various design changes can be made within the scope of the matters described in the claims.

DESCRIPTION OF SYMBOLS 1 Substrate processing apparatus 3 Control unit 5 Spin chuck (substrate holding unit)
7 Water supply unit (Treatment liquid supply unit)
8 EG supply unit (low surface tension liquid supply unit)
9 Hot plate (heating unit)
201 substrate processing apparatus 205 spin chuck (substrate holding unit)
301 substrate processing equipment W substrate

Claims (10)

A substrate processing method for processing the surface of the substrate using a processing liquid,
A substrate holding step of holding the substrate horizontally with the surface of the substrate facing upward,
By supplying a low surface tension liquid having a higher boiling point than the processing liquid and a lower surface tension than the processing liquid to the surface of the substrate on which the processing liquid remains, the surface of the substrate, A mixed liquid-liquid film forming step of forming a liquid film of a mixed liquid of the processing liquid and the low surface tension liquid,
The treatment liquid is evaporated from the liquid film of the mixed liquid formed on the surface of the substrate, and the mixed liquid at the interface between at least the surface of the liquid film of the mixed liquid and the surface of the substrate is subjected to the low surface tension. A replacement step of replacing with a liquid,
Removing the low surface tension liquid from the surface of the substrate, and drying the surface of the substrate,
The replacement step includes heating the liquid film of the mixed liquid after covering the surface of the substrate with the liquid film of the mixed liquid to evaporate the treatment liquid included in the liquid film of the mixed liquid. And a substrate processing method.   2. The substrate processing method according to claim 1, wherein in the mixed liquid heating step, the mixed liquid is heated at a predetermined high temperature higher than a boiling point of the processing liquid and lower than a boiling point of the low surface tension liquid. A substrate processing method for processing the surface of the substrate using a processing liquid,
A substrate holding step of holding the substrate horizontally with the surface of the substrate facing upward,
By supplying a low surface tension liquid having a higher boiling point than the processing liquid and a lower surface tension than the processing liquid to the surface of the substrate on which the processing liquid remains, the surface of the substrate, A mixed liquid-liquid film forming step of forming a liquid film of a mixed liquid of the processing liquid and the low surface tension liquid,
The treatment liquid is evaporated from the liquid film of the mixed liquid formed on the surface of the substrate, and the mixed liquid at the interface between at least the surface of the liquid film of the mixed liquid and the surface of the substrate is subjected to the low surface tension. A replacement step of replacing with a liquid,
Removing the low surface tension liquid from the surface of the substrate, and drying the surface of the substrate,
The drying step,
A liquid film removal region forming step of forming a liquid film removal region in the liquid film of the mixed solution,
A liquid film removal area expanding step of expanding the liquid film removal area toward the outer periphery of the substrate.   4. The substrate processing method according to claim 3, further comprising a paddle step of bringing the substrate into a stationary state or rotating the substrate at a paddle speed about a rotation axis in parallel with the mixed liquid film forming step.   5. The substrate processing method according to claim 3, wherein the liquid film removal region forming step includes a gas blowing step of blowing a gas onto a surface of the substrate.   The substrate processing method according to claim 3, wherein the liquid film removal area enlarging step includes a high-speed rotation step of rotating the substrate at a higher speed than in the mixed liquid-liquid film forming step. The substrate processing method according to claim 5 , wherein the gas includes a high-temperature gas higher than a normal temperature. The treatment liquid contains water,
The substrate processing method according to claim 1, wherein the low surface tension liquid includes ethylene glycol. A substrate holding unit that holds the substrate horizontally and with its surface facing upwards,
A processing liquid supply unit for supplying a processing liquid to the surface of the substrate,
On the surface of the substrate, a low surface tension liquid supply unit for supplying a low surface tension liquid having a higher boiling point than the treatment liquid and having a lower surface tension than the treatment liquid,
A heating unit for heating the liquid film that is formed on a surface of the substrate,
Said processing liquid supply unit, wherein by controlling the low surface tension liquid supply unit and the heating unit, on the surface of the substrate on which the treatment liquid remaining, by supplying the low surface tension liquid, the treatment liquid Forming a liquid film of a liquid mixture of the liquid and the low surface tension liquid, so as to cover the surface of the substrate; and forming the liquid film of the liquid mixture of the liquid mixture formed on the surface of the substrate. A replacement step of evaporating the processing liquid to replace the mixed liquid at the interface between the liquid film of the mixed liquid and the surface of the substrate with the low surface tension liquid; and replacing the low surface tension liquid with the surface of the substrate. And a control unit for performing a drying step of drying the surface of the substrate.
The control unit heats the liquid film of the mixed liquid after covering the surface of the substrate with the liquid film of the mixed liquid to evaporate the processing liquid contained in the liquid film of the mixed liquid in the replacing step. A substrate processing apparatus that executes a mixed liquid heating step. A substrate holding unit that holds the substrate horizontally and with its surface facing upwards,
A processing liquid supply unit for supplying a processing liquid to the surface of the substrate,
On the surface of the substrate, a low surface tension liquid supply unit for supplying a low surface tension liquid having a higher boiling point than the treatment liquid and having a lower surface tension than the treatment liquid,
By controlling the processing liquid supply unit and the low surface tension liquid supply unit to supply the low surface tension liquid to the surface of the substrate on which the processing liquid remains, the processing liquid and the low surface tension liquid are supplied. Forming a liquid film of the mixed liquid with the tension liquid so as to cover the surface of the substrate; and evaporating the processing liquid from the liquid film of the mixed liquid formed on the surface of the substrate. A replacement step of replacing the mixed liquid at the interface between the liquid film of the mixed liquid and the surface of the substrate with the low surface tension liquid, and removing the low surface tension liquid from the surface of the substrate. A control unit that performs a drying step of drying the surface of the substrate,
A liquid film removing area forming step of forming a liquid film removing area in the liquid film of the mixed liquid in the drying step; and a liquid film removing step of expanding the liquid film removing area toward an outer periphery of the substrate. A substrate processing apparatus for performing an area expanding step;

Images