JP2010118498A - Method for processing substrate and substrate processing equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate processing method that can improve in-plane uniformity of processing as well as substrate processing equipment. <P>SOLUTION: Deionized water as a non-corrosive process liquid that does not corrode a substrate W is supplied from a process liquid nozzle 9 to the top face of the horizontally held substrate W to form a liquid film of deionized water on the substrate W. Then a hydrofluoric acid vapor as a corrosive gas or vapor for corroding the substrate W is supplied from a gas or vapor nozzle 12 into a processing chamber C1 that is a sealed space where the substrate W is contained. The hydrofluoric acid vapor supplied into the processing chamber C1 is dissolved into the deionized water on the substrate W, and the liquid film of the deionized water changes to a fluorine acid liquid film. By this method, the whole top surface of the substrate W is uniformly etched. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a substrate processing method and 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 etc. are included.

  In the manufacturing process of a semiconductor device or a liquid crystal display device, an etching process for etching the surface of a substrate such as a semiconductor wafer or a glass substrate for a liquid crystal display device is performed as necessary. A single-wafer type substrate processing apparatus that etches substrates one by one supplies, for example, a spin chuck that horizontally holds and rotates the substrate, and supplies an etching solution to the upper surface (surface) of the substrate held by the spin chuck. And an etchant nozzle.

When etching a substrate with this substrate processing apparatus, for example, while rotating the substrate about a vertical axis passing through the center of the substrate by a spin chuck, the etching solution is continuously supplied from the etching solution nozzle toward the center of the upper surface of the substrate. Discharge. The etchant discharged from the etchant nozzle is deposited on the center of the upper surface of the substrate, receives a centrifugal force due to the rotation of the substrate, and spreads instantaneously toward the peripheral edge of the upper surface of the substrate. Thereby, the etching solution is supplied to the entire upper surface of the substrate, and the etching process is performed on the surface of the substrate.
JP 2003-318154 A

  However, such an etching process has a problem that the etching process on the surface of the substrate becomes uneven in the plane. More specifically, the centrifugal force acting on the etching solution on the substrate increases as the distance from the rotation center increases. Therefore, the flow rate of the etching solution on the substrate also increases as the distance from the rotation center increases, and the supply state of the etching solution to the substrate becomes uneven in the plane. In addition, since the temperature of the processing liquid on the substrate decreases as the distance from the rotation center increases, temperature unevenness occurs in the processing liquid on the substrate. Due to these causes and the like, a difference occurs in the etching rate between the central portion of the surface of the substrate and the peripheral portion of the surface, and the etching process for the surface of the substrate becomes uneven in the plane. Further, in the etching process as described above, since the etching rate is relatively high, there is a problem that the etching amount of the substrate cannot be precisely controlled by a minute amount.

  The above-mentioned problem is common not only when an etching solution is supplied to a rotating substrate and the substrate is etched, but also when a corrosive processing solution that corrodes the substrate is supplied to the rotating substrate and processed. This is a cause of in-plane non-uniformity in substrate processing.

  The present invention has been made under such a background, and an object thereof is to provide a substrate processing method and a substrate processing apparatus capable of improving the in-plane uniformity of processing.

  Another object of the present invention is to provide a substrate processing method and a substrate processing apparatus capable of precisely controlling the corrosion amount of the substrate with a minute amount.

  In order to achieve the above object, according to the first aspect of the present invention, a corrosive gas or vapor that corrodes the substrate (W) can be dissolved, and a non-corrosive treatment liquid that does not corrode the substrate is held horizontally. And supplying the corrosive gas or vapor into the sealed space (C1) in which the substrate is accommodated, and a step of forming a liquid film with the non-corrosive treatment liquid on the substrate. And supplying the corrosive gas or vapor to the liquid film formed on the substrate.

  In this section, alphanumeric characters in parentheses indicate corresponding components in the embodiments described later.

  According to the present invention, a non-corrosive processing liquid that does not corrode a substrate is supplied to the upper surface of the horizontally held substrate, and a liquid film is formed on the substrate by the non-corrosive processing liquid. Then, corrosive gas or vapor that corrodes the substrate is supplied into the sealed space in which the substrate is accommodated. By forming a liquid film with a non-corrosive processing liquid on the substrate, the upper surface of the substrate can be covered with the non-corrosive processing liquid. In addition, by supplying corrosive gas or steam into the sealed space, the corrosive gas or steam is filled in the space, and corrosive gas or steam is applied to the liquid film by the non-corrosive processing liquid. It can be supplied uniformly.

  The non-corrosive processing liquid according to the present invention is a processing liquid capable of dissolving a corrosive gas or vapor. Therefore, the corrosive gas or vapor can be dissolved in the non-corrosive processing liquid by supplying the corrosive gas or vapor to the non-corrosive processing liquid on the substrate. As a result, the liquid film formed by the non-corrosive processing liquid formed on the substrate can be changed to the liquid film formed by the corrosive processing liquid having a uniform concentration. Thereby, the corrosive processing liquid having a uniform concentration can be supplied to the upper surface of the substrate, and the upper surface of the substrate can be uniformly corroded. In addition, since corrosive gas or vapor is gradually dissolved in the non-corrosive processing liquid on the substrate, if the conditions such as concentration and supply amount of corrosive gas or vapor are controlled, the non-corrosive gas or vapor on the substrate The corrosive processing liquid can be changed to an extremely low concentration corrosive processing liquid. Thereby, the rate at which the substrate is corroded can be reduced, and the amount of corrosion of the substrate can be precisely controlled with a minute amount.

  According to a second aspect of the present invention, the step of forming a liquid film with the non-corrosive treatment liquid includes a step of supplying a non-corrosive treatment liquid capable of dissolving water to the upper surface of the substrate, and the corrosion The substrate processing method according to claim 1, wherein the step of supplying the reactive gas or vapor includes a step of supplying a corrosive gas or vapor containing water vapor to the liquid film.

  According to the present invention, the corrosive gas or steam containing water vapor is supplied to the liquid film made of the non-corrosive treatment liquid capable of dissolving water. That is, corrosive gas or vapor having a good affinity for the processing liquid is supplied to the liquid film on the substrate. Therefore, a corrosive gas or vapor is quickly dissolved in the non-corrosive treatment liquid on the substrate, and the liquid film formed by the non-corrosive treatment liquid formed on the substrate is treated with a corrosive treatment with a uniform concentration. The liquid film can be quickly changed to a liquid film. Thereby, corrosion of a board | substrate can be started rapidly.

  According to a third aspect of the present invention, the step of supplying the corrosive gas or vapor containing water vapor to the liquid film includes the step of supplying vapor generated from a corrosive aqueous solution to the liquid film. It is a substrate processing method of description.

  According to the present invention, since the vapor generated from the corrosive aqueous solution is supplied to the non-corrosive processing liquid on the substrate, the corrosive gas or vapor containing water vapor is contained in the non-corrosive processing liquid on the substrate. Can be easily supplied. As a result, the corrosive gas or vapor is quickly dissolved in the non-corrosive processing liquid on the substrate, and the liquid film formed by the non-corrosive processing liquid formed on the substrate is corrosive with a uniform concentration. The liquid film can be quickly changed to a treatment liquid.

  According to a fourth aspect of the present invention, the step of supplying the corrosive gas or vapor includes the step of supplying the corrosive gas or vapor into the sealed space in a state where the substrate is stationary. It is a substrate processing method as described in any one of 1-3.

  According to the present invention, the corrosive gas or vapor is supplied to the sealed space while the substrate is stationary, so that the disturbance of the flow of the corrosive gas or vapor drifting in the sealed space is suppressed or prevented. However, corrosive gas or vapor can be supplied to the non-corrosive processing liquid on the substrate. Accordingly, the corrosive gas or vapor can be more uniformly supplied to the liquid film formed by the non-corrosive processing liquid formed on the substrate.

  According to a fifth aspect of the present invention, the step of supplying the corrosive gas or vapor includes a step of heating the substrate to a predetermined temperature, and a state in which the substrate is heated to the predetermined temperature, and the corrosiveness to the substrate depends on the temperature. The substrate processing method according to claim 1, further comprising a step of supplying a changing corrosive gas or vapor to the liquid film.

  According to this invention, the temperature of the liquid film by the non-corrosive processing liquid formed on the substrate can be increased by heating the substrate to a predetermined temperature. Therefore, when the substrate is heated to a predetermined temperature, corrosive gas or vapor whose corrosiveness to the substrate varies with temperature is supplied into the sealed space, thereby corroding the heated non-corrosive treatment liquid. Sex gas or steam can be supplied. Thereby, the non-corrosive processing liquid on the substrate can be changed to a heated corrosive processing liquid, and the processing state of the substrate by the corrosive processing liquid can be changed. Therefore, the processing state of the substrate can be controlled by adjusting the heating temperature of the substrate.

  According to a sixth aspect of the present invention, the step of supplying the corrosive gas or vapor includes a step of dispersing the corrosive gas or vapor in the sealed space. The substrate processing method according to claim 1.

  According to the present invention, the corrosive gas or vapor is more uniformly distributed with respect to the liquid film formed by the non-corrosive treatment liquid formed on the substrate by dispersing the corrosive gas or vapor in the sealed space. Can be supplied. As a result, the liquid film formed from the non-corrosive processing liquid formed on the substrate can be changed to a liquid film formed from the corrosive processing liquid having a more uniform concentration. Thereby, the upper surface of a board | substrate can be corroded more uniformly.

  The invention according to claim 7 includes a processing chamber (C1) for forming a sealed space for accommodating the substrate (W), a substrate holding means (3) for horizontally holding the substrate in the processing chamber, and corroding the substrate. A treatment liquid supply means (4) for supplying a non-corrosive treatment liquid that can dissolve a corrosive gas or vapor to be produced and does not corrode the substrate to the upper surface of the substrate held by the substrate holding means; and the treatment A gas / vapor supply means (5) for supplying the corrosive gas or vapor into a room and supplying the corrosive gas or vapor to the substrate held by the substrate holding means; and the treatment liquid supply means; Control means (8) for controlling the gas / vapor supply means to supply the corrosive gas or vapor to the substrate on which the liquid film of the non-corrosive treatment liquid is held in the processing chamber. And including A substrate processing apparatus.

  According to the present invention, it is possible to achieve the same effects as those described in relation to the invention of claim 1.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a schematic diagram showing a schematic configuration of a processing unit 1 provided in a substrate processing apparatus according to an embodiment of the present invention.

  The substrate processing apparatus is a single wafer processing apparatus that processes substrates W such as semiconductor wafers one by one. The substrate processing apparatus has a plurality (for example, eight) of processing units 1 that process the substrates W one by one. Eight processing units 1 are arranged in two at four locations separated horizontally. At each location, the two processing units 1 are stacked one above the other.

  Each processing unit 1 is held by the partition wall 2 forming the processing chamber C1 for processing the substrate W, the substrate holding mechanism 3 (substrate holding means) disposed in the processing chamber C1, and the substrate holding mechanism 3. A processing liquid supply mechanism 4 (processing liquid supply means) for supplying a processing liquid to the substrate W, and a gas for supplying a gas or vapor (hereinafter referred to as “gas etc.”) for processing the substrate W into the processing chamber C1. / Vapor supply mechanism 5 (gas / vapor supply means) and a replacement mechanism 6 that exhausts the atmosphere in the processing chamber C1 and supplies gas into the processing chamber C1 to replace the atmosphere in the processing chamber C1. I have. The partition wall 2 is formed in a box shape having a rectangular longitudinal section, and has a sealed space therein. This sealed space is the processing chamber C1.

  The substrate holding mechanism 3 holds a single substrate W horizontally with the upper surface exposed. The substrate holding mechanism 3 may be, for example, a holding type (so-called mechanical chuck) that holds the substrate W by bringing a plurality of holding members into contact with the peripheral end surface of the substrate W. The bottom surface may be adsorbed and the substrate W may be held (so-called vacuum chuck), or other types may be used. The substrate holding mechanism 3 includes a heater 7, and the heater 7 raises the temperature of the substrate W held by the substrate holding mechanism 3 to a predetermined temperature. The heating temperature by the heater 7 is controlled by the control unit 8 (control means). The opening and closing of the valve provided in the substrate processing apparatus is controlled by the control unit 8.

  The processing liquid supply mechanism 4 includes a processing liquid nozzle 9 that discharges the processing liquid and a processing liquid supply pipe 10 that supplies the processing liquid to the processing liquid nozzle 9. The processing liquid nozzle 9 is disposed above the substrate holding mechanism 3 with the discharge port facing downward in the processing chamber C1. The processing liquid nozzle 9 can discharge the processing liquid supplied from the processing liquid supply pipe 10 toward the center of the upper surface of the substrate W. Further, the processing liquid supply pipe 10 is provided with a processing liquid valve 11 for controlling the supply and stop of the processing liquid to the processing liquid nozzle 9.

  As the processing liquid supplied to the processing liquid nozzle 9, a corrosive gas or vapor (hereinafter referred to as “corrosive gas”) that corrodes the substrate W can be dissolved, and the substrate W is not corroded ( When thin films are laminated on the substrate W, a non-corrosive treatment liquid that does not corrode the thin film located on the outermost surface is used. Specifically, for example, any one of alcohols such as pure water (deionized water) and IPA (isopropyl alcohol), electrolytic ion water, magnetic water, and hydrogen water is supplied to the treatment liquid nozzle 9. It is like that. IPA is an example of an alcohol that has higher volatility than pure water and can easily dissolve pure water.

  By opening the processing liquid valve 11 and discharging the processing liquid from the processing liquid nozzle 9, the discharged processing liquid can be deposited on the center of the upper surface of the substrate W. Further, by continuously discharging the processing liquid from the processing liquid nozzle 9, the processing liquid that has landed on the center of the upper surface of the substrate W can be pushed away by the subsequent processing liquid and moved outward on the substrate W. . Therefore, by continuously discharging the processing liquid from the processing liquid nozzle 9, the processing liquid can be accumulated on the substrate W (liquid accumulation), and a liquid film of the processing liquid can be formed on the substrate W. Thereby, the entire upper surface of the substrate W can be covered with the liquid film of the processing liquid.

  The gas / vapor supply mechanism 5 includes a gas / vapor nozzle 12 that discharges gas and the like, and a gas / vapor supply pipe 13 that supplies gas and the like to the gas / vapor nozzle 12. In this embodiment, two gas / vapor nozzles 12 and two gas / vapor supply pipes 13 are provided. For example, the two gas / vapor nozzles 12 are attached to the side wall 2a of the partition wall 2 at positions facing each other with the substrate holding mechanism 3 interposed therebetween in the horizontal direction. Each gas / vapor nozzle 12 is attached to the partition wall 2 so that the discharge port 12a is located in the processing chamber C1. Each gas / vapor nozzle 12 can discharge gas / vapor, for example, in a horizontal direction in the processing chamber C1.

  In the processing chamber C1, two dispersion plates 14 that face the discharge ports 12a of the two gas / vapor nozzles 12 are provided. For example, the dispersion plate 14 is held in a vertical posture so that the central portion thereof faces the discharge port 12 a of the gas / vapor nozzle 12. The gas / vapor discharged from each gas / vapor nozzle 12 strikes the corresponding dispersion plate 14 and is dispersed around the dispersion plate 14. By dispersing the gas / steam, the gas / steam can be quickly distributed in the processing chamber C1.

  The partition wall 2 is connected to a pressure adjusting pipe 15 for adjusting the pressure (atmospheric pressure) in the processing chamber C1. A pressure adjustment valve 16 is interposed in the pressure adjustment pipe 15. When the pressure in the processing chamber C1 becomes a predetermined value or more, the pressure adjusting valve 16 is opened, and the atmosphere in the processing chamber C1 is exhausted. Therefore, when gas / vapor is continuously discharged from the two gas / vapor nozzles 12, the pressure in the processing chamber C1 increases, and the atmosphere in the processing chamber C1 is exhausted from the processing chamber C1. Therefore, when gas / vapor is continuously discharged from the two gas / vapor nozzles 12, the atmosphere in the processing chamber C1 is exhausted, and the atmosphere in the processing chamber C1 is replaced with gas / vapor.

  The gas / steam nozzle 12 is supplied with gas from a gas / steam supply source via a gas / steam supply pipe 19. Examples of the gas supplied to the gas / vapor nozzle 12 include corrosive gases that corrode the substrate W (corresponding to the thin film located on the outermost surface when thin films are formed on the substrate W). It is used. In this embodiment, the vapor of the corrosive aqueous solution is supplied to the gas / vapor supply pipe 19 together with the carrier gas. The upstream ends of the two gas / steam supply pipes 19 are connected to the downstream end of the collective pipe 17, and the vapor of the corrosive aqueous solution supplied to the collective pipe 17 is supplied to the two gas / steam supply pipes 19 together with the carrier gas. Supplied.

  A carrier gas supply pipe 18 that supplies a carrier gas to the collective pipe 17 and a steam supply pipe 19 that supplies a vapor of a corrosive aqueous solution to the collective pipe 17 are connected to the collective pipe 17. A carrier gas flow rate adjusting valve 20 and a carrier gas valve 21 are interposed in the carrier gas supply pipe 18 in order from the upstream side. By opening the carrier gas valve 21, the carrier gas supplied from the carrier gas supply source can be supplied to the collecting pipe 17 at a predetermined flow rate.

  The steam supply pipe 19 is provided with a steam flow rate adjustment valve 22, a first steam valve 23, a tank 24, and a second steam valve 25 in that order from the upstream side. The upstream end of the steam supply pipe 19 is connected to the carrier gas supply pipe 18. Carrier gas is supplied to the vapor supply pipe 19 from a carrier gas supply source common to the carrier gas supply pipe 18.

  The tank 24 stores a corrosive aqueous solution at room temperature or a corrosive aqueous solution adjusted to a predetermined temperature. The tank 24 is filled with a vapor of a corrosive aqueous solution. By opening the first steam valve 23, the carrier gas supplied from the carrier gas supply source can be supplied into the tank 24 at a predetermined flow rate. Further, by opening the first and second steam valves 25, the vapor of the corrosive aqueous solution drifting in the tank 24 can be carried on the carrier gas flow and moved to the downstream side of the steam supply pipe 19.

  The concentration of the vapor of the corrosive aqueous solution in the fluid supplied to the downstream side of the vapor supply pipe 19 can be adjusted by the flow rate of the carrier gas supplied to the tank 24. Specifically, the concentration of the vapor of the corrosive aqueous solution can be increased by increasing the flow rate of the carrier gas supplied to the tank 24 by increasing the opening of the vapor flow rate adjusting valve 22. Further, by reducing the flow rate of the carrier gas supplied to the tank 24 by reducing the opening of the steam flow rate adjusting valve 22, the concentration of the vapor of the corrosive aqueous solution can be lowered.

  By opening the carrier gas valve 21, the first steam valve 23 and the second steam valve 25, the corrosive aqueous solution steam and the carrier gas can be supplied to the collecting pipe 17. The vapor of the corrosive aqueous solution supplied to the collecting pipe 17 can be put on the flow of the carrier gas and sent to the two gas / vapor supply pipes 19. Thus, the vapor of the corrosive aqueous solution can be discharged together with the carrier gas from the two gas / vapor nozzles 12, and the vapor of the corrosive aqueous solution can be filled in the processing chamber C1.

  The concentration of the vapor of the corrosive aqueous solution in the fluid supplied from the gas / vapor nozzle 12 into the processing chamber C1 is adjusted by changing the opening of the carrier gas flow rate adjustment valve 20 and the vapor flow rate adjustment valve 22, for example. be able to. Further, by increasing the opening degree of the carrier gas flow rate adjusting valve 20, the speed of the fluid discharged from the gas / vapor nozzle 12 is increased, and the corrosive aqueous solution vapor is more rapidly dispersed in the processing chamber C1. Can do.

Examples of the carrier gas supplied to the carrier gas supply pipe 18 include inert gases such as nitrogen gas, helium gas, and argon gas. Examples of the corrosive aqueous solution stored in the tank 24 include hydrofluoric acid, sulfuric acid, nitric acid, hydrochloric acid, phosphoric acid, acetic acid, aqueous ammonia, hydrogen peroxide, citric acid, oxalic acid, TMAH, and aqua regia. An etchant containing at least one of them can be exemplified. When a thin film is formed on the surface of the substrate W and the thin film located on the outermost surface is a thin film of SiO ₂ , for example, hydrofluoric acid can be used as an etching solution. Further, when the substrate W is, for example, a silicon wafer and no thin film is formed on the surface thereof, for example, ammonia water can be used as an etching solution.

  The replacement mechanism 6 includes an exhaust pipe 26 for exhausting the atmosphere in the processing chamber C1, a gas nozzle 27 for supplying gas into the processing chamber C1, and a gas supply pipe 28 connected to the gas nozzle 27. I have. An exhaust valve 29 is interposed in the exhaust pipe 26. By opening the exhaust valve 29, the atmosphere in the processing chamber C1 can be exhausted. Further, a gas valve 30 is interposed in the gas supply pipe 28, and gas can be supplied from the gas supply pipe 28 to the gas nozzle 27 by opening the gas valve 30. Examples of the gas supplied to the gas nozzle 27 include inert gas, dry air, and clean air (purified air).

  The gas nozzle 27 is attached to the partition wall 2 such that the discharge port is located in the processing chamber C1. The gas nozzle 27 can discharge the gas supplied from the gas supply pipe 28 in the processing chamber C1. By discharging the gas from the gas nozzle 27 with the exhaust valve 29 opened, the gas discharged from the gas nozzle 27 sends the atmosphere in the processing chamber C1 to the exhaust pipe 26, and the gas is discharged into the processing chamber C1. Can be charged. Thereby, the atmosphere in the processing chamber C <b> 1 can be replaced with the gas discharged from the gas nozzle 27.

  FIG. 2 is a process diagram for explaining an example of the processing of the substrate W by the processing unit 1. 3 to 5 are schematic views of the processing unit 1 for explaining the processing state of the substrate W, respectively. In the following, an example of a process for etching the surface of the substrate W with hydrofluoric acid will be described with reference to FIGS. Moreover, in each process of an example of this process, FIGS. 3-5 is referred suitably.

  The unprocessed substrate W is carried into the processing chamber C1 by a transfer robot (not shown), and is transferred to the substrate holding mechanism 3 with the surface that is a device formation surface facing upward, for example. Then, the processing liquid valve 11 is opened by the control unit 8, and pure water as a non-corrosive processing liquid is continuously discharged from the processing liquid nozzle 9. As shown in FIG. 3, the pure water discharged from the processing liquid nozzle 9 is applied to the center of the upper surface of the stationary substrate W, and is pushed by the subsequent processing liquid and spreads outward on the substrate W. Go. As a result, pure water accumulates (liquid buildup) on the substrate W, and a liquid film of pure water covering the entire upper surface of the substrate W is formed (step S1).

  After the liquid film of pure water is formed on the substrate W, the processing liquid valve 11 is closed by the control unit 8 and the discharge of pure water from the processing liquid nozzle 9 is stopped. Further, while the substrate W is held by the substrate holding mechanism 3, the heater 7 generates heat under the control of the control unit 8 and is held on the substrate W held by the substrate holding mechanism 3 and the substrate W. The pure water liquid film is heated at a predetermined temperature (for example, 80 ° C. or lower).

  Next, in a state where the exhaust valve 29 is closed, the carrier gas valve 21, the first steam valve 23, and the second steam valve 25 are opened by the control unit 8, and the hydrofluoric acid vapor as corrosive gas or the like is transferred to the carrier. It discharges from each gas / vapor nozzle 12 with nitrogen gas as gas. As shown in FIG. 4, the hydrofluoric acid vapor discharged from each gas / vapor nozzle 12 strikes the dispersion plate 14 and is dispersed in the sealed processing chamber C <b> 1. At the same time, the pressure in the processing chamber C <b> 1 increases and the atmosphere in the processing chamber C <b> 1 is exhausted from the pressure adjustment pipe 15. Thereby, the atmosphere in the processing chamber C1 is replaced, and the vapor of hydrofluoric acid is filled in the processing chamber C1 (step S2).

  The hydrofluoric acid vapor supplied into the processing chamber C1 is generated from hydrofluoric acid, which is an aqueous solution of hydrogen fluoride. Therefore, the hydrofluoric acid vapor contains water vapor. Further, the hydrofluoric acid vapor can be dissolved in pure water. Therefore, by filling the treatment chamber C1 with the hydrofluoric acid vapor, the hydrofluoric acid vapor having good affinity is uniformly supplied to the pure water liquid film held on the substrate W to be quickly dissolved. be able to.

  Further, when the hydrofluoric acid vapor is supplied into the processing chamber C1, the configuration of the substrate W held in the substrate holding mechanism 3 and the processing chamber C1 is stationary. Therefore, the hydrofluoric acid vapor can be uniformly dissolved in the liquid film of pure water on the substrate W without causing a disturbance in the flow of the hydrofluoric acid vapor drifting in the processing chamber C1. As a result, the vapor of hydrofluoric acid is uniformly dissolved into the pure water liquid film on the substrate W little by little, and the pure water liquid film on the substrate W is converted into a uniform hydrofluoric acid liquid film having a very low concentration. Can be changed. Therefore, the etching amount of the hydrofluoric acid liquid film is small, and a uniform etching process can be performed on the surface of the substrate W over the entire area.

  The etching rate of the substrate W varies according to processing conditions such as the concentration of hydrofluoric acid vapor supplied to the processing chamber C1. Further, hydrofluoric acid is an etching solution whose corrosiveness to the substrate W changes depending on the temperature. Therefore, by changing the heating temperature by the heater 7 to increase or decrease the temperature of the hydrofluoric acid on the substrate W, The etching rate can be changed. Therefore, the etching rate of the substrate W can be controlled by adjusting the processing conditions such as the concentration of the hydrofluoric acid vapor supplied to the processing chamber C1 and the heating temperature by the heater 7.

  When a predetermined time has elapsed since the supply of the hydrofluoric acid vapor to the processing chamber C1 is started, the control unit 8 closes the carrier gas valve 21, the first vapor valve 23, and the second vapor valve 25, and enters the processing chamber C1. The supply of hydrofluoric acid vapor is stopped. Then, as described later, after the atmosphere in the processing chamber C1 is replaced, the hydrofluoric acid liquid film on the substrate W is washed away, and the etching process on the surface of the substrate W is completed. By performing the etching process with this substrate processing apparatus, the substrate W can be uniformly etched with a small etching amount.

  Exemplifying the specific processing conditions of the etching process, about 100 mL of pure water is held on the substrate W, and the gas / steam nozzle 12 generates steam generated from hydrofluoric acid having a concentration of 40% in a discharge time of 1 to 2 minutes. Discharge from. By performing the etching process under such conditions, the substrate W can be uniformly etched with a minute etching amount of about several to several tens of meters, for example.

  Next, the exhaust valve 29 and the gas valve 30 are opened by the control unit 8, and nitrogen gas, which is an example of gas, is discharged from the gas nozzle 27 as shown in FIG. Nitrogen gas discharged from the gas nozzle 27 spreads into the processing chamber C1. Further, the nitrogen gas discharged from the gas nozzle 27 sends the atmosphere in the processing chamber C1 to the exhaust pipe 26 and exhausts it. Thereby, the atmosphere in the processing chamber C1 is replaced, and the processing chamber C1 is filled with nitrogen gas (step S3). By substituting the atmosphere in the processing chamber C1 with nitrogen gas, it is possible to stop the hydrofluoric acid vapor from being dissolved in the hydrofluoric acid liquid film on the substrate W.

  Next, the processing liquid valve 11 is opened by the controller 8, and pure water is continuously discharged from the processing liquid nozzle 9 again. The pure water discharged from the treatment liquid nozzle 9 is deposited on the center of the upper surface of the stationary substrate W covered with a hydrofluoric acid liquid film, and pushes the hydrofluoric acid on the substrate W outward. Then, hydrofluoric acid and pure water are discharged from the peripheral edge of the substrate W, and the hydrofluoric acid on the substrate W is washed away by the pure water. Further, the processing liquid discharged from the substrate W is drained from the processing chamber C <b> 1 through a drain pipe (not shown) attached to the partition wall 2. In this way, a rinsing process is performed, and hydrofluoric acid is removed from the substrate W (step S4). After the rinsing process is performed for a predetermined time, the control unit 8 closes the processing liquid valve 11 and stops the discharge of pure water from the processing liquid nozzle 9. Then, a drying process for drying the substrate W wet with pure water is performed (step S5).

  The drying process may be performed in the processing chamber C1, or may be performed in a processing chamber different from the processing chamber C1. In the case of performing the drying process in the processing chamber C1, for example, the pure water adhering to the substrate W may be evaporated by irradiating the substrate W with light from the light source, or nitrogen gas or purified from the blower. Pure water may be removed from the substrate W by blowing dry air or the like onto the substrate W. Further, when the drying process is performed in a processing chamber different from the processing chamber C1, pure water is generally removed from the substrate W in the processing chamber C1 so that the processing liquid does not fall during the transfer of the substrate W. Good. In an example of this process, if the drying process is performed in the processing chamber C1 subsequent to the rinsing process, the substrate W can be dried in a nitrogen gas atmosphere. It can be suppressed or prevented.

  As described above, in this embodiment, the corrosive gas or the like is supplied into the processing chamber C1, and the corrosive gas or the like is uniformly applied to the liquid film formed of the non-corrosive processing liquid formed on the substrate W. Supply. Since the non-corrosive processing liquid according to the present embodiment is a processing liquid capable of dissolving a corrosive gas or the like, the corrosive gas or the like is supplied to the non-corrosive processing liquid on the substrate W. By dissolving a corrosive gas or the like in the non-corrosive processing liquid, the liquid film formed by the non-corrosive processing liquid formed on the substrate W is changed to a liquid film formed by the corrosive processing liquid having a uniform concentration. Can be changed. Thereby, the corrosive treatment liquid having a uniform concentration can be supplied to the entire upper surface of the substrate W, and the upper surface of the substrate W can be uniformly corroded. Further, since corrosive gas and the like are gradually dissolved in the non-corrosive processing liquid on the substrate W, if the conditions such as the concentration and supply amount of the corrosive gas are controlled, the non-corrosive gas on the substrate W is controlled. The corrosive processing liquid can be changed to an extremely low concentration corrosive processing liquid. Thereby, the speed | rate at which the board | substrate W is corroded can be made small, and the corrosion amount of the board | substrate W can be precisely controlled by a micro amount.

  Regarding processing uniformity, for example, if a corrosive processing liquid is directly supplied to the substrate W and a liquid film is formed on the substrate W by the corrosive processing liquid, the corrosive processing liquid is supplied to the substrate W. Since the state can be made uniform, it is considered that the processing uniformity can be improved as compared with the case where the corrosive processing liquid is continuously supplied to the rotating substrate W. However, even in such a case, when the corrosive processing liquid is supplied to the substrate W, the corrosive processing liquid is deposited at the position where the corrosive processing liquid is deposited and at other positions. Since the supply state is different, the processing may become uneven in the surface. On the other hand, in the present embodiment, a liquid film made of a non-corrosive processing liquid is formed on the substrate W, and a corrosive gas or the like is uniformly dissolved in the liquid film. The supply state of the corrosive processing liquid to W can be made uniform over the entire surface. Therefore, compared with the case where the corrosive processing liquid is directly supplied to the substrate W to form a liquid film with the corrosive processing liquid on the substrate W, the in-plane uniformity of processing can be improved.

  In the present embodiment, since the corrosive gas is supplied to the liquid film formed by the non-corrosive processing liquid formed on the substrate W to process the substrate W, for example, the corrosive processing liquid is applied to the substrate W. Compared with the case where the substrate W is processed while being continuously supplied, the consumption of the processing fluid (processing liquid, gas, etc.) can be reduced. Thereby, the cost required for processing the substrate W can be reduced. Further, since the amount of the processing liquid supplied to the substrate W is smaller than that in the case of processing the substrate W by continuously supplying the processing liquid to the substrate W, the substrate W is contaminated by the dissolved gas dissolved in the processing liquid. Can be suppressed or prevented. Specifically, for example, it is possible to suppress or prevent the substrate W from being oxidized by carbon dioxide or oxygen dissolved in the processing liquid. Therefore, sufficient processing quality can be ensured even in a process that is very disliked of oxidation of the substrate, such as a process before forming a thin film on a silicon wafer (film formation pre-process).

  Further, in the present embodiment, since the processing is performed without rotating the substrate W in the processing chamber C1, turbulence of the airflow occurs in the processing chamber C1, and foreign matters such as particles drifting in the processing chamber C1 are generated on the substrate W. The adhesion and contamination of the substrate W can be suppressed or prevented. Further, since the processing is performed without rotating the substrate W in the processing chamber C1, a rotating mechanism for rotating the substrate W, and a capturing member for receiving and capturing the processing liquid shaken off from the substrate W along with the rotation. In addition, it is not necessary to provide a blocking member or the like in the processing chamber C1 that blocks the flow of the atmosphere above the substrate W and protects the upper surface of the substrate W from foreign substances. Therefore, the size of the processing unit 1 can be reduced, and the number of processing units 1 can be increased while suppressing or preventing an increase in footprint (occupied area) and height of the substrate processing apparatus. Therefore, it is possible to increase the throughput of the substrate processing apparatus (the number of processed substrates W per unit time) by increasing the number of substrates W that can be processed in parallel by the substrate processing apparatus.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the contents of the above-described embodiments, and various modifications can be made within the scope of the claims. For example, in the above-described embodiment, the case where the two gas / vapor nozzles 12 are attached to the side wall 2a of the partition wall 2 and the gas or the like is discharged horizontally from each gas / vapor nozzle 12 has been described. Absent. Specifically, as shown in FIG. 6, for example, a gas / vapor nozzle 12 is attached to the upper wall 2b of the partition wall 2, and gas or the like is discharged from the gas / vapor nozzle 12 downward from the upper part of the processing chamber C1. May be. Further, as shown in FIG. 7, the gas / vapor nozzle 12 may be attached to the lower end of the partition wall 202 and gas or the like may be discharged from the gas / vapor nozzle 12 upward from the lower part of the processing chamber C1.

  In the processing unit 101 shown in FIG. 6, the gas / vapor nozzle 12 is attached to the upper wall 2 b of the partition wall 2 with the discharge port 12 a facing downward, and the substrate holding mechanism 3 is positioned below the gas / vapor nozzle 12. positioned. A dispersion plate 14 is held in the processing chamber C1 in a horizontal posture, and faces the discharge port 12a of the gas / vapor nozzle 12 from below. A rectifying plate 31 that rectifies the flow of gas or the like is held around the dispersion plate 14 in a horizontal posture. The rectifying plate 31 has a large number of through-holes 32 formed over the entire region, and can circulate gas in the thickness direction. The gas or the like discharged from the gas / vapor nozzle 12 hits the dispersion plate 14 and is dispersed around the dispersion plate 14 and flows downward through the numerous through holes 32. As a result, the flow of gas or the like discharged from the gas / vapor nozzle 12 can be rectified to form a uniform flow of gas or the like downward in the processing chamber C1. Accordingly, the non-corrosive processing liquid on the substrate W is discharged by discharging a corrosive gas or the like from the gas / vapor nozzle 12 in a state where a liquid film is formed by the non-corrosive processing liquid on the substrate W. Corrosive gas or the like can be uniformly supplied from above.

  Further, in the processing unit 201 shown in FIG. 7, the vertical section of the partition wall 202 has a fan shape that widens upward. The gas / vapor nozzle 12 is attached to the lower end portion of the partition wall 202 with the discharge port 12a facing upward, and the substrate holding mechanism 3 is positioned above the gas / vapor nozzle 12. A dispersion plate 14 is held in a horizontal posture in the processing chamber C1 and faces the discharge port 12a of the gas / vapor nozzle 12 from above. The gas or the like discharged from the gas / vapor nozzle 12 strikes the dispersion plate 14 and is dispersed around the gas, and flows along the side wall 202 a of the partition wall 202. Then, gas or the like flows along the arc-shaped upper wall 202b whose longitudinal section is convex upward. As gas flows along the side wall 202a and the upper wall 202b of the partition wall 202, the gas discharged from the gas / vapor nozzle 12 is dispersed in the processing chamber C1.

  Further, in the example of the processing of the substrate W described above, the case where the processing fluid (pure water and vapor of hydrofluoric acid) is supplied to the substrate W while the substrate W is stationary has been described. For example, a rotation mechanism for rotating the substrate W held by the substrate holding mechanism 3 around a vertical axis passing through the center thereof is provided, and the substrate W is rotated at a predetermined rotation speed (for example, a low rotation speed of about 10 to 30 rpm). In this state, pure water may be supplied to the substrate W. Alternatively, the hydrofluoric acid vapor may be supplied into the processing chamber C1 while the substrate W is rotated at a predetermined rotational speed, and the hydrofluoric acid vapor may be supplied to the pure water on the substrate W. Further, in the case where a rotation mechanism is provided, when the drying process is performed in the processing chamber C1, the substrate W may be rotated at a high speed by the rotation mechanism to remove the processing liquid adhering to the substrate W (spin dry).

  In the example of the processing of the substrate W described above, the case where pure water is used as the non-corrosive processing liquid has been described. However, the present invention is not limited to this. For example, IPA (isopropyl alcohol; IPA) with a concentration of 5% may be used. Since IPA is an alcohol that can easily dissolve pure water, it is less corrosive gas containing water vapor or hydrofluoric acid as steam than when pure water is used as a non-corrosive treatment liquid. The vapor can be quickly dissolved in the liquid film on the substrate W. Thereby, the liquid film made of IPA formed on the substrate W can be quickly changed to the liquid film made of hydrofluoric acid. Therefore, the etching of the substrate W can be started quickly.

In the example of the processing of the substrate W described above, the case of using hydrofluoric acid vapor as corrosive vapor has been described. However, the present invention is not limited to this. For example, anhydrous hydrofluoric acid gas, ammonia gas, hydrogen chloride gas, A gas containing any one of nitrogen gas and SO ₃ gas, or a mixed gas of two or more of these gases may be used as the corrosive gas. In addition, a mixture of the aforementioned gas and a vapor of an organic solvent such as methanol, or a mixture of the aforementioned gas and a vapor of an organic solvent with a carrier gas such as an inert gas is used as a corrosive gas. Also good.

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

It is a schematic diagram which shows schematic structure of the process unit with which the substrate processing apparatus which concerns on one Embodiment of this invention was equipped. It is process drawing for demonstrating an example of the process of the board | substrate by a process unit. It is a schematic diagram of the processing unit for demonstrating the processing state of a board | substrate. It is a schematic diagram of the processing unit for demonstrating the processing state of a board | substrate. It is a schematic diagram of the processing unit for demonstrating the processing state of a board | substrate. It is a schematic diagram of the processing unit which concerns on other embodiment of this invention. It is a schematic diagram of the processing unit which concerns on further another embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Processing unit 3 Substrate holding | maintenance mechanism 4 Processing liquid supply mechanism 5 Gas / vapor supply mechanism 8 Control part 101 Processing unit 201 Processing unit C1 Processing chamber W Substrate

Claims (7)

A non-corrosive treatment solution that does not corrode the substrate can be dissolved in a corrosive gas or vapor that corrodes the substrate, and is supplied to the upper surface of the horizontally held substrate. Forming a liquid film with the treatment liquid;
Supplying the corrosive gas or vapor into a sealed space in which the substrate is accommodated, and supplying the corrosive gas or vapor to the liquid film formed on the substrate. . The step of forming a liquid film with the non-corrosive treatment liquid includes a step of supplying a non-corrosive treatment liquid capable of dissolving water to the upper surface of the substrate,
The substrate processing method according to claim 1, wherein the step of supplying the corrosive gas or vapor includes a step of supplying a corrosive gas or vapor containing water vapor to the liquid film.   The substrate processing method according to claim 2, wherein the step of supplying the corrosive gas or vapor containing water vapor to the liquid film includes the step of supplying vapor generated from the corrosive aqueous solution to the liquid film.   The step of supplying the corrosive gas or vapor includes a step of supplying the corrosive gas or vapor into the sealed space in a state where the substrate is stationary. The substrate processing method as described in 2. above.   The step of supplying the corrosive gas or vapor includes a step of heating the substrate to a predetermined temperature, and a corrosive gas or vapor in which the corrosiveness to the substrate changes depending on the temperature in a state where the substrate is heated to the predetermined temperature. The substrate processing method as described in any one of Claims 1-4 including the process of supplying to a said liquid film.   The substrate processing method according to claim 1, wherein the step of supplying the corrosive gas or vapor includes a step of dispersing the corrosive gas or vapor in the sealed space. A processing chamber for forming a sealed space for accommodating a substrate;
Substrate holding means for holding the substrate horizontally in the processing chamber;
A processing liquid supply means that can dissolve a corrosive gas or vapor that corrodes the substrate and supplies a non-corrosive processing liquid that does not corrode the substrate to the upper surface of the substrate held by the substrate holding means;
A gas / vapor supply means for supplying the corrosive gas or vapor into the processing chamber and supplying the corrosive gas or vapor to the substrate held by the substrate holding means;
Controlling the treatment liquid supply means and the gas / vapor supply means to supply the corrosive gas or vapor to the substrate on which the liquid film of the non-corrosive treatment liquid is held on the upper surface in the treatment chamber A substrate processing apparatus.

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