JP2001044165A - Substrate processing method and apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To satisfactorily remove a processing solution from a substrate to be processed, without the use of organic solvents. SOLUTION: In this substrate processing method, a substrate W to be processed is immersed in a processing solution 30 in a processing bath 10 for solution processing, and then the substrate W is exposed from the processing solution 30 to remove the solution 30 on the substrate. At this time, an electric field is applied to the processing solution 20 to form a current on the surface of the solution, a magnetic field B is applied to the processing solution 30 to impart an electromagnetic force F to a current I, thereby removing the processing solution 30 from the surface of the exposed substrate W.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for processing a substrate, such as a semiconductor wafer or a glass substrate for an LCD, by immersing the substrate in a cleaning solution such as a chemical solution or a rinsing solution, cleaning the substrate, and then drying the substrate. Things.

[0002]

2. Description of the Related Art Generally, in a manufacturing process of a semiconductor manufacturing apparatus, a substrate to be processed (hereinafter, referred to as a wafer or the like) such as a semiconductor wafer or LCD glass is subjected to a chemical solution or a rinsing solution (cleaning solution).
A cleaning method of sequentially immersing in a processing tank in which a processing liquid such as the above is stored for cleaning is widely adopted.

Further, in such a cleaning apparatus, a dry gas consisting of a volatile organic solvent such as IPA (isopropyl alcohol) is brought into contact with the surface of a wafer or the like after cleaning, so that the dry gas is removed. A drying apparatus for condensing or adsorbing vapor to remove and dry water from a wafer or the like is provided.

A conventional cleaning / drying apparatus of this type stores (contains) a chemical solution such as hydrofluoric acid or a rinsing liquid (cleaning liquid) such as pure water, and attaches the stored chemical solution or cleaning liquid to a substrate to be processed. A cleaning tank (cleaning chamber) in which semiconductor wafers W (hereinafter, referred to as wafers) are immersed, a drying unit positioned above the cleaning tank, and a plurality of, for example, 50, wafers W held and held in the cleaning tank. A cleaning / drying processing apparatus including a moving unit that moves to a drying unit, for example, a wafer boat, is known.

As a conventional drying treatment method, there is known a technique described in Japanese Patent Application Laid-Open No. 2-291128 or Japanese Patent Publication No. 6-103686. Of these,
In the drying technique described in Japanese Patent No. -291128, a drying process is performed in a process as shown in FIG. That is, first, the wafer W is immersed in the processing bath 2 in which the cleaning liquid, for example, the pure water 1 overflows, to be cleaned. At this time, an inert gas such as N2 gas is supplied into the processing chamber 3 to replace the inside of the processing chamber 3 with N2 gas (FIG. 4A).

Next, a dry gas 4 composed of a vapor of a volatile solvent such as IPA (isopropyl alcohol) is used.
Is supplied into the processing chamber 3 to form a thin liquid film of IPA on the surface of pure water (FIG. 4B). Then, the wafer W is pulled up into the processing chamber 3 above the processing tank 2 by a holding means for holding the wafer W, for example, the wafer boat 5, and the IPA is brought into contact with the cleaned wafer W, and the vapor of the dry gas 4 is condensed. Alternatively, the wafer W is removed by suction and absorbed by the Marangoni effect (difference in surface tension) (FIG. 4C). Thereafter, N2 gas is supplied into the processing chamber 3 to eliminate the IPA gas in the processing chamber 3 (FIG. 4D).
Further, the inside of the processing chamber 3 is depressurized to promote evaporation of residual moisture and IPA adhering to the groove of the wafer boat 5 to complete the drying process (FIG. 4E).

As described above, in this type of conventional drying treatment method, after a wafer is immersed in pure water and washed, the wafer and pure water are relatively moved to form an IPA formed on the surface of pure water.
The liquid film and the dry gas (IPA gas) are brought into contact with the wafer surface, and the vapor of the dry gas is condensed or adsorbed to remove and dry the moisture of the wafer.

[0008]

SUMMARY OF THE INVENTION However, IPA
In the case of a method in which a drying gas made of a volatile organic solvent such as (isopropyl alcohol) is brought into contact with the drying gas and the vapor of the drying gas is condensed or adsorbed to remove and dry the moisture of the wafer and the like, the drying performance is reduced. However, the use of an organic solvent for drying requires not only labor for exhaustion and waste liquid treatment, but also is not good for the environment. In order to ensure safety, it was necessary to provide a CO2 digester and the like.

The Marangoni effect (difference in surface tension)
In the method of removing and drying water from a wafer or the like, the drying efficiency was not so good.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a substrate processing method and a substrate processing apparatus which can remove a processing liquid from a substrate to be processed without using an organic solvent. Things.

[0011]

SUMMARY OF THE INVENTION According to the present invention, in a substrate processing apparatus of this type, when a substrate to be processed is pulled up from the processing liquid, the processing liquid is applied between the substrate and the processing liquid by surface tension. Although the force for adhering to the substrate acts, the treatment liquid can be removed from the surface of the substrate to be treated by applying a force larger than the surface tension. The means is electromagnetic force.

(1) In the substrate processing method according to the first aspect, after the substrate to be processed is immersed in a processing liquid in a processing chamber and subjected to liquid processing, the substrate to be processed is exposed from the processing liquid and the processing liquid on the surface of the substrate is processed. When removing the processing liquid, an electric field is applied to the processing liquid to form a current on the liquid surface, a magnetic field is applied to the processing liquid, an electromagnetic force is applied to the current, and the processing liquid is removed from the exposed surface of the substrate to be processed. It is characterized by.

That is, this is a substrate processing method which forms a magnetic field near the water surface, allows a current to flow near the water surface, and utilizes an electromagnetic force (Lorentz force) acting on an object through which the current flows. A method, for example, a washing / drying method is provided. Since the interfacial drying method does not use an organic solvent, the method has an advantage that adhesion of particles is small. The direction of the electromagnetic force may be any direction as long as the processing liquid is consequently removed from the exposed surface of the substrate to be processed, and may be vertical or obliquely downward with respect to the surface of the processing liquid.

(2) A substrate processing method according to a second aspect is characterized in that an electric field and a magnetic field are applied to the processing liquid so that the electromagnetic force has a downward component.

For example, when a semiconductor wafer W as a processing substrate is lifted from a cleaning chamber as a processing chamber to a drying chamber above the cleaning chamber, as shown in FIG. 3, the cleaning liquid as a processing liquid is raised to a position slightly higher than the liquid surface due to surface tension. It is considered that the state is attached to the substrate to be processed (wafer W). Therefore, for example, when the magnetic field B and the current I are taken in the direction of FIG. 3 and the downward electromagnetic force F is applied at right angles or obliquely to the water surface of the cleaning liquid,
The cleaning liquid attached to the substrate to be processed by surface tension can be efficiently removed.

(3) A substrate processing method according to a third aspect of the present invention is characterized in that the processing liquid is brought into contact with a gas that ionizes the processing liquid and facilitates the formation of the liquid flow. This gas may be either CO2 gas or a mixed gas of CO2 and N2 (claim 4).

(4) A substrate processing method according to claim 5, wherein at least one of the magnitude of the electric field or the magnitude of the magnetic field is varied.

According to this feature, the processing liquid can be vibrated by changing the magnitude of the downward electromagnetic force applied to the processing liquid, and the processing liquid can be efficiently removed from the substrate to be processed. In this case, the processing liquid can be more efficiently removed by increasing the electric and magnetic fields.

(5) The substrate processing method according to claim 6, wherein the electric field and the magnetic field are synchronized to generate the electromagnetic force in a fixed direction.

According to this feature, pulsating DC or AC can be used for the electric field source and the magnetic field source.

(6) The substrate processing method according to the seventh aspect is characterized in that hot water is used as the processing liquid.

By using warm water as the treatment liquid, drying can be performed efficiently.

(7) In the substrate processing method according to the eighth aspect of the present invention, in the liquid processing, after forming a protective oxide film as a protective film, the substrate to be processed is exposed from the processing liquid, and the processing is performed from the surface of the substrate to be processed. The liquid is removed.

As described above, by actively forming the protective oxide film on the substrate to be processed before the drying process, the substrate can be protected against the subsequent drying process and the like.

(8) The substrate processing method according to the ninth aspect is characterized in that a treatment with hydrofluoric acid is performed before the formation of the protective oxide film to remove the natural oxide film.

The surface of the wafer after the removal of the natural oxide film is in an activated state, which means that the natural oxide film is easily formed again. Therefore, the formation of the natural oxide film can be suppressed by actively forming the clean protective oxide film on the surface of the substrate to be processed after removing the natural oxide film.

(9) A substrate according to a tenth aspect, comprising: a processing chamber for storing a processing liquid for processing a substrate to be processed; and an exposing means for exposing the substrate to be processed from the processing liquid in the processing chamber. The processing apparatus is characterized in that, at least in the vicinity of the opening of the processing chamber, an electrode for supplying a current to the processing liquid is provided, and a magnetic pole for generating a magnetic field in a direction different from the current is provided. In this case, the magnetic pole may be formed by an electromagnetic coil and an iron core, the power supply of the electromagnetic coil may be an AC power supply, and the power supply of the electrode may be an AC power supply.

By configuring the apparatus in this way, when the substrate to be processed is lifted from the processing chamber, the processing liquid may adhere to the substrate due to surface tension between the surface of the substrate and the processing liquid. The power to work works. This force is suppressed by a downward electromagnetic force (Lorentz force) produced by the electrode plate and the electromagnetic coil, is apparently weakened, and good removal and drying can be performed. Unlike the conventional method, since the interfacial drying method does not use an organic solvent, the method has an advantage that adhesion of particles is small.

The exposing means preferably includes a moving mechanism for holding the substrate to be processed and moving it upward from the processing chamber, for example, an elevating mechanism for lifting the substrate to be processed from the cleaning chamber to the drying chamber above it ( Claim 12). Also,
The exposure unit may include a drain port provided at the bottom of the processing chamber, a drain pipe connected to the drain port, and an on-off valve interposed in the drain pipe. (Claim 13).

(10) The substrate processing apparatus according to claim 14, wherein the electrodes and the magnetic poles are arranged such that the electromagnetic force generated in the processing liquid by the current and the magnetic field has a downward component.

When a substrate to be processed is lifted from, for example, a cleaning chamber to a drying chamber above the cleaning chamber, it is considered that the cleaning liquid adheres to the substrate to a position slightly higher than the liquid level due to surface tension. Therefore, when a downward or vertical electromagnetic force is applied to the water surface of the cleaning liquid, the cleaning liquid attached to the substrate to be processed due to surface tension can be efficiently removed.

(11) In the substrate processing apparatus according to the fifteenth aspect, at least one of an ozone water generating means and a hot water generating heating means is provided in a pipe for supplying the processing liquid to the processing chamber. I do.

According to this structure, a clean oxide film can be easily and positively formed on the substrate before lifting the substrate.

(12) In the substrate processing apparatus according to the present invention, a drying chamber capable of sealingly surrounding the upper part of the processing chamber is provided, a gas supply means is provided in the drying chamber, and the gas supply means is connected to a gas supply source. Is connected.

According to this configuration, for example, either the CO 2 gas or the mixed gas of CO 2 and N 2 is supplied to the processing liquid, and the processing liquid is ionized to easily form the current or the liquid flow. it can.

(13) A substrate processing apparatus according to a seventeenth aspect of the present invention is characterized in that the apparatus further comprises magnetic pole moving means for displacing the arrangement of the magnetic poles.

According to this structure, the arrangement of the magnetic poles can be changed by the magnetic pole moving means, so that the processing liquid can be efficiently removed from the substrate according to the inclination of the substrate to be processed and the irregularities on the surface of the substrate. can do.

[0038]

Embodiments of the present invention will be described below in detail with reference to the drawings. In this embodiment, a case where the present invention is applied to a semiconductor wafer cleaning / drying processing apparatus will be described.

FIG. 1 is a schematic view showing a first embodiment of a cleaning / drying processing apparatus according to the present invention, and FIG. 2 is a schematic view showing a system configuration of the cleaning / drying processing apparatus.

In FIG. 2, the cleaning / drying apparatus stores (contains) a chemical such as hydrofluoric acid or a rinsing liquid (cleaning liquid) such as pure water, and applies the stored chemical or cleaning liquid to the substrate to be processed. A processing chamber 10 (processing chamber) in which a certain semiconductor wafer W (hereinafter, referred to as a wafer W) is immersed, a drying chamber 20 positioned above the processing chamber 10, a plurality of, for example, 50 wafers are held and Inside of processing tank 10 and drying room 2
The moving mechanism (exposure means) that moves into the inside of the main body 0, here, for example, is mainly constituted by an elevating mechanism composed of a wafer boat 40, for example.

The processing tank 10 is formed of a material having high corrosion resistance and chemical resistance, for example, a quartz member or polypropylene, and is provided with an inner tank 10a and an inner tank disposed outside the upper end of the inner tank 10a. And an outer tank 10b for receiving the overflowing cleaning liquid from 10a. In the processing tank 10, a chemical liquid / cleaning liquid supply nozzle 11 (hereinafter, referred to as a liquid supply nozzle) for supplying a chemical liquid or a cleaning liquid to the wafer W located in the processing tank 10 is provided on both lower sides thereof. A chemical liquid or pure water is supplied by a switching valve 15 from a chemical liquid supply source 14 and a pure water supply source 13 connected to the liquid supply nozzle 11 via a pipe 12, and the chemical liquid or pure water is supplied into the treatment tank 10. Is to be stored.
Further, in the middle of the pipe 12, a halogen lamp type heating means 16 for generating hot water and an ultraviolet irradiation type ozone water generating means 17 for positively forming a clean oxide film are provided. Reference numeral 18 denotes a flow meter.

A drain port is provided in the center of the bottom of the processing tank 10, and a drain valve 1 serving as an open / close valve is provided at the drain port.
The drain pipe (drainage pipe) 19a is connected via 9. The drain port, the drain pipe, and the on-off valve constitute an exposure unit that exposes the wafer W as a substrate to be processed from the processing liquid in the processing chamber.

The drying chamber 20 is made of a material having high corrosion resistance and chemical resistance, for example, quartz, similarly to the processing tank 10. A gas diffusion nozzle 21 for preventing the water surface from being disturbed by wind pressure is provided at an upper part in the drying chamber 20, and the gas diffusion nozzle 21 is connected to an N 2 gas source 23 and a CO 2 source 24 via a pipe 22. Have been. In addition, 25 is a manual valve, 26 is a high pressure gauge, and 27 and 28 are flow meters.

In order to generate the Lorentz force in the present invention, a pair of electrode plates 31 for supplying a DC current to the cleaning liquid 30 in the lateral direction are provided in the vicinity of the opening of the processing tank 10 so as to face each other. As shown in FIG. 1, the first DC power supply 3
2 is connected. As a result, current flows from the positive electrode to the negative electrode. In the vicinity of the opening of the processing tank 10,
As shown in FIG. 1, a pair of magnetic poles that generate a magnetic field in a direction orthogonal to the DC current and apply a downward electromagnetic force to the water surface of the cleaning liquid 30 are used, and are arranged opposite to each other. In this case, for example, an electromagnetic coil 33 is used together with the iron core 34 as the magnetic pole. The pair of electromagnetic coils 33 are electrically connected in series so as to be connected to the second DC power supply 35 such that when one of the electromagnetic coils has the N pole, the other has the S pole. The first DC power supply 32
And the second DC power supply 35 are turned ON-O by the control means 36.
FF control is performed.

The directions of the electric field E generated by the electrode plate 31 and the magnetic field B generated by the electromagnetic coil 33 are orthogonal to each other in the plane of the cleaning liquid 30, and are directed downward with respect to the plane of the cleaning liquid 30 according to Fleming's left-hand rule. An electromagnetic force (Lorentz force) in the direction of. Therefore, when the wafer W is lifted, the adhesive acts between the wafer W and the cleaning liquid 30 in a direction to reduce the adhesive force.

Next, an example of the operation of the cleaning / drying apparatus will be described.

First, with the wafer W being moved into the processing tank 10, the switching valve 15 is switched to the side of the chemical supply source 14, and the chemical is stored in the processing tank 10 and overflows.
An HF aqueous solution is supplied to the wafer W placed in the chamber 0 to perform a chemical solution process.

Next, after draining the chemical solution after the chemical solution treatment, the switching valve 15 is switched to the pure water supply source 13 side to store a cleaning solution, for example, pure water in the processing tank 10 and overflow a small amount to perform the cleaning process. Apply.

Next, the ozone water generating means 17 is operated,
By applying ozone water, a clean protective oxide film is positively formed on the wafer W. Thereafter, the heating means 16 is operated to heat the pure water to make it hot water.

Next, the wafer W was removed from pure water under the following conditions.
Is slowly raised to generate an electromagnetic force having a downward component in the pure water flowing on the surface of the wafer W at the liquid level, and the pure water to be pulled up together with the wafer W is pushed down and removed.

First, with a small amount of the pure water overflowing, a CO 2 gas or a mixed gas of CO 2 and N 2 is supplied to the pure water from a supply port 29 provided on the upper surface of the drying chamber 20 through a gas diffusion nozzle 21. In addition, the pure water is ionized to lower the specific resistance of the pure water near the water surface, thereby facilitating the flow of current.

In this state, the pair of electrode plates 31 is connected (ON) to the first DC power supply 32 by a signal from the control means 36. When an electric field is applied by the electrode plate 31, a weak current I flows in one direction along the water surface in the surface layer of the pure water having the reduced specific resistance.

The pair of electromagnetic coils 33 are connected to the second DC power supply 35 by a signal from the control means 36 (O
N). Due to the electromagnetic coil 33, the surface layer of pure water
A magnetic flux B is generated in a direction orthogonal to the current I in the same water surface. As the total action of both the current I and the magnetic flux B,
According to Fleming's left-hand rule, a downward electromagnetic force acts on the surface of pure water.

However, the power source applied to the electrode plate 31 and the electromagnetic coil 33 may be not only a DC power source but also a power source whose size varies, for example, an AC power source. In this case, either the electrode plate 31 or the electromagnetic coil 33 may apply AC power, or both may apply AC power. Please note that
The direction of the electromagnetic force determined by the direction of the generated current and magnetic field is
The electrode plate 31 and the electromagnetic coil 3 have a desired constant direction, for example, in the present embodiment, a component in a downward direction.
3 and synchronizing the AC power supply. With this configuration, the magnitude of the electromagnetic force applied to the liquid flow fluctuates, causing acceleration to occur in the electromagnetic force, in other words, a state in which an impact force is generated, and removing the pure water with momentum. can do.

In the above state, the wafer W once immersed in pure water is pulled up to the drying chamber 20 at a low speed. Normally, when the wafer W is exposed from the pure water interface, pure water adheres to the surface of the wafer W due to surface tension, and the pure water adheres to the surface of the wafer W to a position higher than the pure water interface. it is conceivable that. However, as described above, since the electromagnetic force of Fleming's left-hand rule acts on the surface layer of the pure water due to the current (electrons) passing through the magnetic field, the water molecules near the wafer W are pulled downward. . At this time, a Marangoni effect is generated, and the wafer surface above the pure water interface is a surface from which pure water has been removed.

Thus, no pure water remains on the surface of the wafer W. For completeness, when the lifting is completed, the supply from the supply port 29 is made only N2 gas, and the water is further completely removed by hot N2 blow and dried.

As described above, the present cleaning / drying apparatus immerses the wafer W having been subjected to the cleaning process once in a pure water rinse layer, and pulls up the wafer W from pure water at a low speed, whereby water droplets are formed on the surface of the wafer W. Can be achieved.
It should be noted that no water droplets are left on the surface of the wafer W, and when the lifting is completed, the wafer W is further completely removed by hot N2 blow.

In short, according to the cleaning / drying method of this embodiment, a wafer W as a substrate to be processed is placed in a processing tank 1 as a processing chamber.
After the wafer W is immersed in the cleaning liquid 30 and cleaned, the wafer W is pulled up from the processing tank 10 to the drying chamber 20 above the processing chamber 10 to perform a drying process. Thus, a downward electromagnetic force is applied to the water surface of the cleaning liquid 30 to reduce the adhesive force acting between the wafer W and the cleaning liquid 30 when the wafer W is lifted. Further, the apparatus of this embodiment includes a processing tank 10 for storing a cleaning liquid 30 for cleaning the wafer W, a drying chamber 20 disposed above the processing tank 10, and pulling the wafer W from the processing tank 10 to the drying chamber 20. Elevating mechanism such as wafer boat 4
0 in the cleaning / drying processing apparatus provided with
In the vicinity of the opening 0, there is provided an electrode plate 31 for flowing a direct current in the cleaning liquid 30 in a lateral direction, and an electromagnetic coil 33 for generating a magnetic field in a direction perpendicular to the direct current to apply a downward electromagnetic force to the water surface of the cleaning liquid 30. And the adhesive force acting between the wafer W and the cleaning liquid 30 when the wafer W is lifted is reduced by the electromagnetic force.

The cleaning / drying method according to the above-described embodiment is a so-called interfacial drying method, and there is no need to set the inside of the drying chamber 20 to an IPA gas atmosphere as in the prior art, so that it is easy to handle and is excellent as an environmental measure. ing.

In the above embodiment, the Lorentz force is applied in a direction perpendicular to the water surface of the cleaning liquid. However, the direction in which the magnetic field is generated is slightly changed, and the electromagnetic force is applied obliquely downward to the water surface of the cleaning liquid. It can also be done.

Hereinafter, embodiments in these cases will be described.

FIG. 4 is a schematic view showing a second embodiment of the cleaning / drying processing apparatus according to the present invention. In this cleaning / drying processing apparatus, a pair of magnetic poles 51 (specifically, composed of an electromagnetic coil and an iron core) opposed to each other with the processing tank 10 interposed therebetween is supported by a bifurcated holding arm 52. I have.
The holding arm 52 includes a rotating device 5 serving as a magnetic pole moving unit.
3 and rotatably supported by a pair of electrodes 31.
The magnetic pole 51 can be rotated in a plane perpendicular to the facing direction. By changing the direction of the magnetic field B formed by the magnetic poles 51, the direction of the electromagnetic force (Lorentz force) can be set to a desired direction. In the second embodiment, other parts are the same as those in the first embodiment, and the description is omitted.

Next, a specific processing method using such a washing / drying apparatus will be described.

FIG. 5 shows a case where the direction of the magnetic field B is set obliquely upward. By doing so, the electromagnetic force F
Can be generated obliquely downward from the back surface R of the wafer W toward the pattern surface P. Therefore, F _V is generated as the vertical direction component force against the the wafer W, the process liquid from the pattern surface P by the component force F _V can strongly pulled apart, drying can be accelerated.

FIG. 6 shows a case where the direction of the magnetic field B is set upward and the wafer W is arranged obliquely. In this case, the electromagnetic force F will be exerted in the horizontal direction, the vertical direction component force F _V for the wafer W is applied in a direction away from the pattern plane P of the wafer W. Therefore, also in this case, the processing liquid can be strongly separated from the pattern surface P, and drying can be promoted.

FIG. 7 shows a case where holes are formed on the surface of the wafer W. In this case, the direction of the magnetic field B is set vertically upward, and the wafer W is arranged vertically. In this case, the electromagnetic force F acts in the same horizontal direction as the direction of the holes H formed on the pattern surface P. Therefore, the processing liquid remaining at the bottom of the hole H can be drawn out and dried sufficiently.

FIG. 8 shows a case where a relatively large projection M is formed on the surface P of the wafer W, and the wafer W is arranged vertically. In this case, to change the direction of the magnetic field B in accordance with the liquid level is gradually lowered to S _2, S ₃ from S _1, and changing the direction of the electromagnetic force from F ₁ to F _2, F _3. That is, when the liquid surface S ₁ is located slightly above the upper end of the convex portion M, the electromagnetic force F ₁ is applied in the horizontal direction, and when the liquid surface S ₂ is located on the side surface of the convex portion M, , vertically downward electromagnetic force F _2, when the liquid surface S ₃ is in contact with the lower end surface of the convex portion M, the electromagnetic force F ₃
To face diagonally downward. By doing so, the processing liquid adhering to the projection M can be efficiently separated.

FIG. 9 shows a case where two pairs of magnetic poles (not shown) are used to form magnetic fields B ₁ and B ₂ in opposite directions, respectively, on both sides of a vertically arranged wafer W. By doing so, on both surfaces of the wafer W, electromagnetic forces F ₁ and F ₂ are generated in a direction perpendicular to and separate from the wafer surface, and the processing liquid on both surfaces of the wafer W is efficiently separated from the wafer surface.

In the above-described embodiment, a description is given of a batch-type washing and drying process. However, the present invention is not limited to this and can be applied to a single-wafer process.

[0070]

As described above, according to the present invention, the following excellent effects can be obtained.

(1) According to the substrate processing method of the first aspect, after the substrate to be processed is immersed in the processing liquid in the processing chamber and subjected to the liquid treatment, the substrate to be processed is exposed from the processing liquid to remove the surface of the substrate to be processed. In removing the processing liquid, an electric field is applied to the processing liquid to form a current on the liquid surface, and a magnetic field is applied to the processing liquid to apply an electromagnetic force to the current, thereby removing the processing liquid from the exposed surface of the substrate to be processed. Therefore, an interfacial drying method is provided as a novel washing / drying method that does not use an organic solvent. Since an organic solvent is not used, there is an advantage that handling is easy, and adhesion of particles is small.

(2) According to the cleaning / drying method of the second aspect, since the magnetic field is applied so that the electromagnetic force is directed downward with respect to the water surface of the processing liquid, the magnetic force is applied to the substrate to be processed by surface tension. The used processing solution can be efficiently removed.

(3) According to the substrate processing method of the third and fourth aspects, prior to the application of the downward electromagnetic force, the processing liquid is brought into contact with a gas which ionizes the processing liquid and makes it easier to flow an electric current. Thus, good conductivity can be imparted even when the processing liquid is pure water.

(4) According to the substrate processing method of the fifth aspect, at least one of the magnitude of the electric field and the magnitude of the magnetic field is varied to vary the magnitude of the electromagnetic force applied to the processing liquid. Therefore, the processing liquid can be efficiently removed from the substrate to be processed.

(5) According to the substrate processing method of the sixth aspect, the electric field and the magnetic field are synchronized to generate the electromagnetic force in a fixed direction. AC can be used.

(6) According to the substrate processing method of the present invention, since hot water is used as the processing liquid, drying can be performed efficiently.

(7) According to the substrate processing method of the eighth aspect, in the above liquid processing, after forming a protective oxide film as a protective film, the substrate to be processed is exposed from the processing liquid, and the surface of the substrate to be processed is formed. Since the processing solution is removed from the substrate, the substrate to be processed can be stably protected against a subsequent drying process or the like.

(8) According to the substrate processing method of the ninth aspect, before the formation of the protective oxide film, a treatment with hydrofluoric acid is performed to remove the natural oxide film, so that the surface of the substrate to be processed is removed. In this way, a clean protective oxide film can be positively formed.

(9) According to the substrate processing apparatus of the present invention, a processing chamber for storing a processing liquid for processing a substrate to be processed, and a processing chamber for storing the processing substrate in the processing chamber. An exposure means for exposing from the liquid, at least near the opening of the processing chamber,
An electrode that allows current to flow through the processing solution and a magnetic pole that generates a magnetic field in a direction different from the current are provided, so that no organic solvent is used, and therefore, there is no interfacial drying and cleaning / drying of the interface drying method. A device can be obtained.

(10) According to the substrate processing apparatus of the present invention, the electrodes and the magnetic poles are arranged so that the electromagnetic force generated in the processing liquid by the current and the magnetic field has a downward component. The liquid can be efficiently removed.

(11) According to the substrate processing apparatus of the fifteenth aspect, in the middle of the pipe for supplying the processing liquid to the processing chamber,
Since at least one of the ozone water generating means and the heating means for generating hot water is provided, a clean protective oxide film can be easily and positively formed on the substrate before being pulled up.

(12) According to the substrate processing apparatus of the present invention, a drying chamber capable of sealingly enclosing the upper part of the processing chamber is provided, a gas supply means is provided in the drying chamber, and the gas supply means is provided with a gas supply means. Since it is configured to be connected to the supply source, the processing liquid is supplied with, for example, either a CO2 gas or a mixed gas of CO2 and N2, and the processing liquid is ionized to easily form the current or the liquid flow. Can be.

(13) According to the substrate processing apparatus of the seventeenth aspect, since the magnetic pole moving means for displacing the arrangement of the magnetic poles is provided, the arrangement of the magnetic poles can be changed by the magnetic pole moving means. The processing liquid can be efficiently removed from the substrate in accordance with the inclination of the substrate and the irregularities on the surface of the substrate.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an electromagnetic force generation unit of a first embodiment of a substrate processing apparatus according to the present invention.

FIG. 2 is a schematic diagram showing a system configuration of a substrate processing apparatus according to the present invention.

FIG. 3 is a schematic view for explaining a substrate processing method according to the present invention.

FIG. 4 is a schematic view of an electromagnetic force generation unit of a second embodiment of the substrate processing apparatus according to the present invention.

FIG. 5 is another schematic diagram for explaining the substrate processing method according to the present invention.

FIG. 6 is still another schematic diagram for explaining the substrate processing method according to the present invention.

FIG. 7 is still another schematic diagram for explaining the substrate processing method according to the present invention.

FIG. 8 is still another schematic diagram for explaining the substrate processing method according to the present invention.

FIG. 9 is still another schematic diagram for explaining the substrate processing method according to the present invention;

FIG. 10 is a schematic cross-sectional view illustrating a drying process of a conventional substrate processing apparatus.

[Explanation of symbols]

 W Semiconductor wafer (substrate to be processed) 10 Processing tank (processing chamber) 12 Piping 16 Heating means 17 Ozone water generating means 20 Drying chamber 21 Gas diffusion nozzle 24 CO2 source 30 Cleaning liquid 31 Electrode plate 32 First DC power supply 33 Electromagnetic coil ( Magnetic pole) 34 Iron core 35 Second DC power supply 36 Control means 40 Wafer boat (elevating mechanism) 51 Magnetic pole 53 Rotating device (magnetic pole moving means)

Claims (17)

[Claims] An electric field is applied to the processing liquid when the substrate to be processed is immersed in a processing liquid in a processing chamber and subjected to liquid processing, and then the substrate is exposed from the processing liquid to remove the processing liquid from the surface of the processing substrate. A substrate processing method, comprising forming a current on a liquid surface, applying a magnetic field to the processing liquid, applying an electromagnetic force to the current, and removing the processing liquid from the exposed surface of the substrate to be processed. 2. The substrate processing method according to claim 1, wherein an electric field and a magnetic field are applied to the processing liquid so that the electromagnetic force has a downward component. 3. The substrate processing method according to claim 1, wherein the processing liquid is brought into contact with a gas which ionizes the processing liquid to facilitate formation of the liquid flow. 4. The substrate processing method according to claim 3, wherein said gas comprises a CO2 gas or a mixed gas of CO2 and N2. 5. The substrate processing method according to claim 1, wherein at least one of the magnitude of the electric field and the magnitude of the magnetic field is varied. 6. The electric field and the magnetic field are synchronized to generate the electromagnetic force in a fixed direction.
The substrate processing method according to the above. 7. The substrate processing method according to claim 1, wherein hot water is used as the processing liquid. 8. In the liquid processing, after forming a protective oxide film as a protective film, the substrate to be processed is exposed from the processing liquid,
8. The substrate processing method according to claim 1, wherein the processing liquid is removed from a surface of the substrate to be processed. 9. The substrate processing method according to claim 8, wherein a treatment with hydrofluoric acid is performed before forming the protective oxide film to remove the natural oxide film. 10. A substrate processing apparatus comprising: a processing chamber for storing a processing liquid for processing a substrate to be processed; and an exposing means for exposing the processing substrate from the processing liquid in the processing chamber. An apparatus for processing a substrate, comprising: an electrode near the opening that allows a current to flow through a processing liquid; 11. The apparatus according to claim 1, wherein the magnetic pole is formed by an electromagnetic coil and an iron core, a power supply of the electromagnetic coil is an AC power supply, and a power supply of the electrode is an AC power supply.
0 substrate processing apparatus. 12. The substrate processing apparatus according to claim 10, wherein said exposing means includes a moving mechanism for holding said substrate to be processed and moving it upward from a processing chamber. 13. The exposure means includes a drain port provided at the bottom of the processing chamber, a drain pipe connected to the drain port, and an on-off valve interposed in the drain pipe. The substrate processing apparatus according to any one of claims 10 to 12, wherein: 14. The substrate processing apparatus according to claim 10, wherein the electrodes and the magnetic poles are arranged such that the electromagnetic force generated in the processing liquid by the current and the magnetic field has a downward component. 15. The substrate processing apparatus according to claim 10, wherein at least one of an ozone water generating unit and a heating unit for generating hot water is provided in the middle of a pipe for supplying a processing liquid to the processing chamber. 16. A drying chamber capable of sealingly surrounding the upper part of the processing chamber, providing a gas supply means in the drying chamber, and connecting the gas supply means to a gas supply source. 16. The substrate processing apparatus according to any one of items 15 to 15. 17. The apparatus according to claim 10, further comprising magnetic pole moving means for displacing the arrangement of said magnetic poles.
Or the substrate processing apparatus according to 14.