JPH11265867A - Treatment of substrate and substrate treating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a foreign matter from being adhered at the exposed region on the surface of a substrate material by a method wherein a substrate is dipped into a chemical and thereafter, when the substrate in a state of the surface, which is mixedly provided with the exposed region on the surface of the substrate material and a film formation region, is immersed into pure water to clean the substrate, a surface active agent is added into the chemical and/or the pure water. SOLUTION: A silicon wafer W in the state of the surface, which is mixedly provided with a bare silicon region and an SiO2 film formation region, is put in a chemical tank 12, a prescribed amount of a surface active agent is previously added into a chemical (a hydrofluoric acid 10) in the tank 12 and under the condition where the chemical is evenly mixed with the surface active agent, the wafer W is put into the tank 12 and the wafer W is immersed into the hydrofluoric acid 10 to perform a cleaning or etching treatment on the wafer W. The surface active agent is orientated on the surface of the wafer W and in the case where an anion surface active agent is used, a hydrophilic group turned into a negativity is orientated on the side of the surface of the wafer W, a zeta potential in the surface of the wafer W is turned into a negative potential and the wettability of the surface of the wafer W is enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a semiconductor wafer,
The present invention relates to a substrate processing method and a substrate processing apparatus for cleaning or etching a substrate such as a glass substrate for a liquid crystal display device and an electronic component with a chemical solution and then cleaning the substrate with pure water.

[0002]

2. Description of the Related Art In a semiconductor device manufacturing process, for example, unnecessary substances attached to the surface of a substrate, for example, a silicon wafer, are removed, and a silicon oxide film (SiO ₂ ) and a silicon nitride film (Si ₃ When adjusting the film such as N ₄ ) to a desired film thickness or removing unnecessary portions according to a predetermined pattern, a chemical solution such as hydrofluoric acid, phosphoric acid aqueous solution, ammonia water, hydrogen peroxide solution or the like is used. The wafer is cleaned or etched, and thereafter foreign substances such as a chemical solution and reaction products remaining on the wafer are removed by cleaning with pure water. When performing this processing using a multi-tank type immersion treatment apparatus, the wafer is carried into a chemical solution tank containing a chemical solution such as hydrofluoric acid, and the wafer is immersed in the chemical solution to be washed or etched. After this,
The wafer is carried out of the chemical tank, the wafer is carried into a washing tank containing pure water, and the wafer is immersed in pure water to be washed with pure water.

[0003]

When a silicon wafer is washed or etched with a chemical solution using a multi-tank type immersion treatment apparatus and then washed with pure water, the surface of the wafer carried into the chemical solution tank originally has When the wafer material surface, that is, the exposed region of the silicon surface (hereinafter, referred to as “bare silicon region”) and the region where a film such as a silicon oxide film is formed are mixed, and the wafer is carried into the washing tank, ,
When the bare silicon region and the film formation region are mixed on the surface of the wafer, or when the surface of the wafer carried into the chemical solution tank is covered with the film and the wafer is contained in the chemical solution contained in the chemical solution tank. When the wafer is carried into the rinsing tank, the bare silicon area and the film forming area are mixed on the surface of the wafer when the wafer is carried into the washing tank by being immersed in the chemical tank. In chemicals, foreign substances such as colloidal SiO-based compounds (S
i, O, and F) are generated, and when the wafer is carried into the washing tank with the chemical solution containing the foreign matter adhered to the surface of the wafer, the pure water contained in the washing tank is In the process of immersion and cleaning of the wafer, foreign matter adheres to the bare silicon region on the surface of the wafer, thereby contaminating the wafer. A similar problem is that a plurality of silicon wafers housed in a wafer holder include a wafer having a bare silicon area (including a wafer having a bare silicon surface on the entire surface) and a wafer having a surface on which a coating such as a silicon oxide film is formed. It also occurs when they are mixed. That is,
At least, when a wafer holder containing a plurality of wafers is carried into the washing tank, if a wafer having a bare silicon region and a wafer having a film forming surface are mixed, the pure water contained in the washing tank is mixed. In the process of immersing a plurality of wafers in water and cleaning them, foreign substances in the chemical solution generated in the chemical solution tank and attached to the surface of the wafer are exposed to the bare silicon surface of the surface of the wafer adjacent to the wafer. Attached to
The wafer will be contaminated.

[0004] The present invention has been made in view of the above-described circumstances, and after cleaning or etching a substrate by immersing the substrate in a chemical solution, cleaning the substrate by immersing the substrate in pure water. When the substrate is immersed in pure water, even if the exposed region of the substrate material surface and the film forming region are mixed on the surface of the substrate, the substrate and the film having the exposed region of the substrate material surface Even when a substrate having a formation surface is mixed, it is possible to prevent foreign matter from adhering to an exposed region of the substrate material surface of the substrate and contaminating the substrate in a process of cleaning the substrate with pure water. It is an object of the present invention to provide a substrate processing method capable of performing the method and a substrate processing apparatus capable of suitably performing the method.

[0005]

Means for Solving the Problems Claims 1 and 2
The invention relates to a substrate processing in which a substrate in a surface state in which an exposed region of a substrate material surface and a film forming region are mixed is immersed in pure water for cleaning after the substrate is immersed in a chemical solution and washed or etched. In the method, a surfactant is added to the chemical solution and / or the pure water in the invention according to claim 1, and an alcohol is added in the invention according to claim 2, respectively.

[0006] Each of the inventions according to claims 3 and 4 is:
After cleaning or etching by immersing a plurality of substrates in a chemical solution, cleaning by immersing a plurality of substrates in which a substrate having an exposed region of the substrate material surface and a substrate having a film forming surface are mixed in pure water In the substrate processing method, a surfactant is added to the chemical solution and / or the pure water in the invention according to claim 3, and an alcohol is added in the invention according to claim 4. .

According to a fifth aspect of the present invention, in the substrate processing method according to any one of the first to fourth aspects, hydrofluoric acid is used as a chemical solution for cleaning or etching the substrate.

According to a sixth aspect of the present invention, there is provided a chemical solution tank for storing a chemical solution and immersing a substrate in the chemical solution to perform a cleaning process or an etching process, and a pure water for storing the same.
A substrate in which the exposed region of the substrate material surface and the film forming region are mixed, or a plurality of substrates in which the substrate having the exposed region of the substrate material surface and the substrate having the film forming surface are mixed, are immersed in pure water. In a substrate processing apparatus provided with a washing tank for performing a cleaning process, and a substrate transfer means for transferring a substrate from the chemical tank to the washing tank, the substrate processing apparatus includes: A surfactant or an alcohol is added to the stored pure water.

According to the substrate processing method of each of the first and third aspects of the present invention, a zeta potential (electrokinetic potential) on the surface of the substrate is added by adding a surfactant to a chemical solution and / or pure water. ) And the zeta potential of the particle surface of the foreign matter generated when the substrate is immersed in the chemical solution and washed or etched, have the same sign, respectively.
As a result, the surface of the substrate and the particle surface of the foreign matter electrically repel each other. That is, when the substrate is immersed in a chemical solution or pure water, the surfactant is oriented on the surface of the substrate. For example, when an anionic surfactant is used, the surface of the substrate has a negative hydrophilic group. Are oriented, and the zeta potential on the substrate surface becomes negative. On the other hand, foreign substances generated during the cleaning or etching of the substrate, for example, colloidal SiO-based compounds,
The anionic surfactant is oriented on the particle surface, and the zeta potential on the particle surface of the foreign substance becomes negative similarly to the above.
As a result, the surface of the substrate and the particle surface of the foreign matter electrically repel each other. For this reason, even if the exposed region of the substrate material surface and the film-forming region are mixed on the surface of the substrate, the substrate having the exposed region of the substrate material surface and the substrate having the film-formed surface on a plurality of substrates are also different. Even if they are mixed, it is possible to prevent foreign matter from adhering to the exposed region of the substrate material surface of the substrate in the process of immersing the substrate in pure water and cleaning.

Further, by adding a surfactant to the chemical solution and / or pure water, the wettability of the surface of the substrate immersed in the chemical solution or pure water is improved. That is, the bare silicon surface of a substrate, for example, a silicon wafer becomes a hydrophobic silicon clean surface or a hydrogen-terminated (terminal) silicon surface in a chemical solution, for example, hydrofluoric acid, but a surfactant is present in hydrofluoric acid. By doing
The contact angle of the wafer surface with the solution is reduced, and the wettability is improved. As a result, when the wafer is taken out of the chemical solution and immersed in pure water, the bare silicon surface of the wafer becomes hydrophilic, is covered with the solution, and does not come into contact with air, so that the foreign matter (Particles) are hardly generated, and a gas-liquid interface is not formed on the bare silicon surface of the wafer, so that foreign matters are hardly generated at the gas-liquid interface. Therefore, when the wafer is taken out of the chemical solution and immersed in pure water, foreign substances do not occur and adhere to the bare silicon surface of the wafer. Further, the presence of the surfactant in the pure water reduces the contact angle of the surface of the wafer with the pure water, thereby improving the wettability. As a result, the bare silicon surface of the wafer becomes hydrophilic and is covered with pure water containing a surfactant, so that foreign substances hardly adhere to the bare silicon surface of the wafer.

According to the second and fourth aspects of the present invention, the alcohol is added to the chemical solution and / or the pure water so that the substrate is immersed in the chemical solution for cleaning or etching. The contaminants, for example, a colloidal SiO-based compound, generated at this time are solvated with alcohols and stabilized. For this reason, even if the exposed region of the substrate material surface and the film-forming region are mixed on the surface of the substrate, the substrate having the exposed region of the substrate material surface and the substrate having the film-formed surface on a plurality of substrates are also different. Even if they are mixed, it is possible to prevent foreign matter from adhering to the exposed region of the substrate material surface of the substrate in the process of immersing the substrate in pure water and cleaning.

Further, by adding alcohols to the chemical solution and / or pure water, the wettability of the surface of the substrate immersed in the chemical solution or pure water is improved, and a surfactant is added. As in the case described above, the above-described operation prevents foreign matter from adhering to the exposed region of the substrate material surface of the substrate.

According to a fifth aspect of the present invention, there is provided a substrate processing method comprising:
As described above, even when the substrate is washed or etched with hydrofluoric acid to generate foreign matter, for example, a colloidal SiO-based compound including Si, O, and F,
The foreign matter does not adhere to the exposed region of the substrate material surface of the substrate.

In the substrate processing apparatus according to the present invention, a surfactant or an alcohol is added to the chemical solution contained in the chemical tank and / or the pure water contained in the washing tank. Accordingly, as described above, foreign matter is prevented from adhering to the exposed region of the substrate material surface of the substrate.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram showing an example of a schematic configuration of a substrate processing apparatus used to carry out a substrate processing method according to the present invention. This apparatus is provided with a chemical solution tank 12 in which a chemical solution, for example, hydrofluoric acid (aqueous HF solution) 10 is stored, and a washing tank 16 in which ultrapure water 14 is stored. A chemical solution inlet is formed at the bottom of the chemical solution tank 12, and a chemical solution supply pipe 18 is connected to the chemical solution inlet, and hydrofluoric acid is continuously supplied into the chemical solution tank 12 through the chemical solution supply pipe 18. It is supposed to be. The chemical liquid tank 12 is provided with an overflow liquid receiving portion 20, and the chemical liquid tank 1
The hydrofluoric acid that has overflowed from the upper part of 2 flows into the overflow liquid receiving portion 20. A drain pipe 22 communicates with the overflow liquid receiving section 20, and the hydrofluoric acid flowing into the overflow liquid receiving section 20 is discharged through the drain pipe 22 and is circulated. Then, a plurality of substrates to be processed, for example, silicon wafers W, are stored in a wafer holder (not shown), put into the chemical solution tank 12, and immersed in the hydrofluoric acid 10. Even when a wafer is put into the chemical solution tank 12, even if a bare silicon region and a film, for example, a region where a silicon oxide film is formed, are mixed on the surface, or the entire surface is covered with the film, either will do. Alternatively, even if a wafer having a bare silicon region and a film, for example, a wafer having a surface on which a silicon oxide film is formed, are mixed on a plurality of wafers housed in the wafer holder, the film is formed on the surface of all the wafers. Or either of them. The silicon wafer W immersed in the hydrofluoric acid 10 housed in the chemical solution tank 12 is cleaned or the coating is partially etched.

A pure water inlet is formed at the bottom of the washing tank 16, and a pure water supply pipe 24 is connected to the pure water introduction port.
Pure water is continuously supplied to the inside. The overflow tank 26 is provided with an overflow water receiving portion 26, and the pure water overflowing from the upper portion of the flush tank 16 flows into the overflow water receiving portion 26. Overflow water receiving part 26
Is connected to a drain pipe 28, and the pure water flowing into the overflow water receiving portion 26 is discharged through the drain pipe 28. Then, the plurality of silicon wafers W stored in the wafer holder unloaded from the chemical solution tank 12 are put into the washing tank 16 and immersed in the ultrapure water 14. When the wafer is put into the washing tank 16, a bare silicon region and a film (silicon oxide film) forming region are mixed on the surface. Alternatively, for a plurality of wafers stored in a wafer holder,
A wafer having a bare silicon region and a wafer having a coating (silicon oxide film) forming surface are mixed. Wash tank 1
The silicon wafer W immersed in the ultrapure water 14 housed in 6 is washed to remove foreign substances and hydrofluoric acid on its surface.

In this apparatus, a surfactant or an alcohol, for example, isopropyl alcohol (hereinafter, referred to as isopropyl alcohol) is used.
"IPA") is supplied into the washing tank 16 to supply ultrapure water 1
4 is provided with an additive supply pipe 30 for adding a surfactant or IPA. Alternatively, as shown by a two-dot chain line in FIG. 1, a surfactant or IPA is supplied toward the inside of the chemical solution tank 12 and the surfactant or IPA is supplied into the hydrofluoric acid 10.
An additive supply pipe 32 for adding A is provided. Note that additive supply pipes 30 and 32 for supplying a surfactant or IPA to both the washing tank 16 and the chemical solution tank 12 may be provided.

Next, a method for processing a substrate using the substrate processing apparatus as shown in FIG. 1 will be described with reference to a plurality of embodiments.

First, a silicon wafer W in a surface state in which a bare silicon region and a SiO ₂ formation region are mixed is placed in a chemical solution tank 1.
Insert into 2. At this time, a chemical solution previously stored in the chemical solution tank 12, for example, 50% hydrofluoric acid (50% HF aqueous solution):
A surfactant is added to hydrofluoric acid 10 prepared at a mixing ratio of pure water = 1: 100, for example, so as to have a concentration of about 100 ppm, and the solution is sufficiently circulated or stirred.
The silicon wafer W is charged into the chemical solution tank 12 with the solution being uniform. And hydrofluoric acid 10 in the chemical solution tank 12
A cleaning or etching process is performed by immersing the silicon wafer W therein. At this time, the surfactant is oriented on the surface of the wafer W. For example, when an anionic surfactant is used, the negative hydrophilic group is oriented on the surface side of the wafer W and the surface of the wafer W is oriented. Has a negative zeta potential.
In addition, since the surfactant is added to the hydrofluoric acid 10, the wettability of the surface of the silicon wafer W immersed in the hydrofluoric acid 10 is improved.

As the processing in the chemical solution tank 12 progresses, the etching of the SiO ₂ existing on the surface of the silicon wafer W progresses, and fine foreign matters such as colloidal SiO-based compounds are generated in the solution. Also, with respect to this foreign substance, the anionic surfactant is oriented on the particle surface, and the zeta potential on the particle surface of the foreign substance becomes negative as described above. As a result of such a phenomenon, the surface of the wafer W and the particle surface of the foreign matter have negative zeta potentials of the same sign, and repel each other. Therefore, foreign matter does not adhere to the surface of the wafer W.

When the processing in the chemical solution tank 12 is completed, the silicon wafer W is unloaded from the chemical solution tank 12 and is washed in the washing tank 16.
It is thrown in. At this time, as described above, the surface of the silicon wafer W is improved in wettability, becomes hydrophilic, becomes covered with the solution, and does not come into contact with air, so that foreign matter (particles) hardly occurs. Further, since no gas-liquid interface is formed on the surface of the wafer W, foreign matters are less likely to be generated at the gas-liquid interface. Therefore, when the wafer W is taken out of the hydrofluoric acid 10 in the chemical solution tank 12 and immersed in the ultrapure water 14 in the washing tank 16, foreign matter is generated and adheres to the bare silicon region on the surface of the wafer W. No such thing happens.

The silicon wafer W carried into the washing tank 16 is washed by being immersed in, for example, ultrapure water 14 at a flow rate of about 20 L / min to remove foreign substances and hydrofluoric acid on its surface. Is done. Incidentally, SiO ₂ on the surface of the wafer W when a silicon wafer W is loaded into the washing tank 16
When a hydrophilic portion such as is present, the wafer W is charged into the washing tank 16 with hydrofluoric acid containing foreign matter adhered to the surface. However, by cleaning the wafer W with the ultrapure water 14, even if the surfactant is gradually released from the surface of the wafer W, the bare silicon region on the surface of the wafer W has a low pH during hydrofluoric acid treatment. PH at the end of washing from the state =
The zeta potential remains negative until around 7 or a high pH state, and the pH value of the ultrapure water 14 in the washing tank 16 is 6 to 7 at the same time as the surfactant on the surface of the foreign particles is released. Therefore, the zeta potential becomes negative, so that no foreign matter adheres to the bare silicon region on the surface of the wafer W.

The hydrofluoric acid 1 contained in the chemical tank 12 is
The same effect as described above can be obtained by adding a surfactant to the ultrapure water 14 contained in the washing tank 16 instead of adding the surfactant to the water. That is, before the silicon wafer W, which has been treated with the hydrofluoric acid 10 in the chemical solution tank 12, is put into the washing tank 16, the ultrapure water 14 in the washing tank 16 is added.
When a surfactant is added to the inside and sufficiently mixed, the surface of the silicon wafer W immersed in the ultrapure water 14 in the washing tank 16 is oriented on the surface thereof. When the system surfactant is used, the negative hydrophilic group is oriented on the surface side of the wafer W, and the zeta potential on the surface of the wafer W becomes negative. On the other hand, S on the surface of the wafer W
Even for foreign substances such as SiO-based compounds contained in hydrofluoric acid adhering to hydrophilic portions such as iO ₂ and mixed in the ultrapure water 14 in the washing tank 16, an anionic surfactant is formed on the surface of the particles. Are oriented, and the zeta potential on the particle surface of the foreign matter becomes negative. As a result, the surface of the wafer W and the particle surface of the foreign matter have a negative zeta potential of the same sign, and repel each other, so that the surface of the wafer W has a bare silicon region. Foreign matter is prevented from adhering. Further, the presence of the surfactant in the ultrapure water 14 improves the wettability of the surface of the wafer W, and as a result, the bare silicon region on the surface of the wafer W becomes hydrophilic, and Therefore, foreign matters are less likely to adhere to the bare silicon region on the surface of the wafer W.

Next, the silicon wafer W in the surface state in which the bare silicon region and the SiO ₂ formation region are mixed is placed in the chemical tank 1.
At the time of injection into the chemical solution 2, alcohols, for example, I in a chemical solution previously stored in the chemical solution tank 12, for example, hydrofluoric acid 10 prepared at a mixing ratio of 50% hydrofluoric acid: pure water = 1: 100.
PA is added, for example, in an amount of about 100 ml, and the solution is sufficiently circulated or stirred, and the silicon wafer W is charged into the chemical solution tank 12 in a state where the solution is uniform. Then, the silicon wafer W is immersed in the hydrofluoric acid 10 in the chemical solution tank 12 to perform cleaning or etching. At this time, since the IPA is added to the hydrofluoric acid 10, even if a small foreign substance such as a colloidal SiO-based compound is generated in the solution when the wafer W is treated with the hydrofluoric acid, the foreign substance is not removed. It is solvated with IPA and stabilized. Therefore, foreign matter does not adhere to the surface of the wafer W. Further, since IPA is added to the hydrofluoric acid 10 in the chemical solution tank 12, the wettability of the surface of the silicon wafer W immersed in the hydrofluoric acid 10 is improved.

When the processing in the chemical solution tank 12 is completed, the silicon wafer W is unloaded from the chemical solution tank 12 and is washed in the washing tank 16.
It is thrown in. At this time, as described above, since the surface of the silicon wafer W has improved wettability, foreign substances (particles) are unlikely to be generated similarly to the case where a surfactant is added, and the surface of the wafer W Since no gas-liquid interface is formed, foreign matter is less likely to be generated at the gas-liquid interface. Therefore, when the wafer W is taken out of the hydrofluoric acid 10 in the chemical solution tank 12 and immersed in the ultrapure water 14 in the washing tank 16, foreign matter is generated and adheres to the bare silicon surface of the wafer W. Nothing happens.

The silicon wafer W carried into the washing tank 16 is washed by being immersed in, for example, ultrapure water 14 at a flow rate of about 20 L / min to remove foreign substances and hydrofluoric acid on the surface thereof. Is done. At this time, the silicon wafer W
Since the surface of the wafer W is charged into the washing tank 16 with the surface in a hydrophilic state, foreign substances hardly adhere to the bare silicon region on the surface of the wafer W in the process of being washed with the ultrapure water 14.

The hydrofluoric acid 1 stored in the chemical solution tank 12
The same effect as described above can be obtained by adding IPA to the ultrapure water 14 contained in the washing tank 16 instead of adding IPA to the water. That is, hydrofluoric acid 1 in the chemical solution tank 12
The silicon wafer W, which has been processed by the process
Before being charged into the inside, the IP is put into the ultrapure water 14 in the washing tank 16.
A, for example, about 100 ml is added and mixed well, and the silicon wafer W carried into the washing tank 16 is immersed in, for example, ultrapure water 14 at a flow rate of about 20 L / min for cleaning. In this case, even if a foreign substance such as a colloidal SiO-based compound generated when the wafer W is treated with hydrofluoric acid is included in the hydrofluoric acid and mixed into the ultrapure water 16 in the washing tank 14, The foreign matter is solvated with IPA and stabilized. This prevents foreign matter from adhering to the surface of the wafer W. Further, the presence of IPA in the ultrapure water 14 improves the wettability of the surface of the wafer W,
Since the bare silicon region on the surface of the wafer W becomes hydrophilic and is covered with pure water containing IPA, foreign substances are less likely to adhere to the bare silicon region on the surface of the wafer W.

In the above-described embodiment, a case has been described in which a silicon wafer W having a surface state in which a bare silicon region and a SiO ₂ formation region are mixed is processed, but a plurality of sheets of the same processing lot stored in a wafer holder are processed. Silicon wafer with bare silicon area and SiO
₂ and a wafer having a film-formed surface (such as a silicon wafer on the front side and a SiO ₂
The present invention is similarly applied to the case where a plurality of wafers having a surface on which a coating film is formed are stored in a wafer holder, and the same effects as described above can be obtained.

[0030]

According to the substrate processing method of each of the inventions according to claims 1 to 4, after the substrate is immersed in a chemical solution and washed or etched, the substrate is immersed in pure water for cleaning. When the substrate is immersed in pure water, even if the exposed region of the substrate material surface and the film forming region are mixed on the surface of the substrate, the substrate having the exposed region of the substrate material surface on a plurality of substrates Even if there is a mixture of a substrate having a film-forming surface and the substrate, in the process of cleaning the substrate with pure water,
It is possible to prevent foreign matter from adhering to the exposed region of the substrate material surface of the substrate and contaminating the substrate.

In the substrate processing method of the invention according to claim 5,
Even if a foreign substance, for example, a colloidal SiO-based compound composed of Si, O and F is generated by cleaning or etching the substrate with hydrofluoric acid, the foreign substance adheres to an exposed area of the substrate material surface of the substrate and Can be prevented from being contaminated.

When the substrate processing apparatus according to the sixth aspect of the present invention is used, the above effects can be obtained by suitably executing the substrate processing methods according to the first to fourth aspects of the present invention.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an example of a schematic configuration of a substrate processing apparatus used to carry out a substrate processing method according to the present invention.

[Explanation of symbols]

W Silicon wafer 10 Hydrofluoric acid 12 Chemical tank 14 Ultrapure water 16 Rinse tank 18 Chemical supply pipe 24 Pure water supply pipe 30, 32 Surfactant or alcohol additive supply pipe

Claims (6)

[Claims] 1. A substrate processing method of immersing a substrate in a chemical solution to clean or etch the substrate, and then immersing the substrate in a surface state in which an exposed region of a substrate material surface and a film-forming region are mixed in pure water for cleaning. The substrate processing method according to claim 1, wherein a surfactant is added to the chemical solution and / or the pure water. 2. A substrate processing method of immersing a substrate in a chemical solution to wash or etch the substrate, and then immersing the substrate in a surface state in which an exposed region of the substrate material surface and a film forming region are mixed in pure water to clean the substrate. The method according to any one of claims 1 to 3, wherein an alcohol is added to the chemical solution and / or the pure water. 3. After washing or etching a plurality of substrates by immersing the substrates in a chemical solution, the substrates having an exposed region of the substrate material surface and a substrate having a film formation surface are mixed together in pure water. A substrate processing method for washing by immersing in a substrate, wherein a surfactant is added to the chemical solution and / or the pure water. 4. After immersing a plurality of substrates in a chemical solution and washing or etching the substrates, a plurality of substrates in which a substrate having an exposed region of a substrate material surface and a substrate having a film formation surface are mixed are mixed with pure water. A substrate processing method for washing by immersing in a substrate, wherein an alcohol is added to the chemical solution and / or the pure water. 5. The substrate processing method according to claim 1, wherein the chemical for cleaning or etching the substrate is hydrofluoric acid. 6. A chemical solution tank for containing a chemical solution and immersing a substrate in the chemical solution to perform a cleaning process or an etching process, and containing pure water and exposing an exposed region of a substrate material surface in the pure water. A water washing tank that performs a pure water cleaning process by immersing a plurality of substrates in which a substrate having a film forming region and a substrate having a film forming surface and a substrate having an exposed region of a substrate material surface and a substrate having a film forming surface are mixed. And a substrate transfer means for transferring a substrate from the chemical tank to the washing tank. In the substrate processing apparatus, the substrate is transferred into a chemical solution contained in the chemical tank and / or pure water contained in the washing tank. A substrate processing apparatus to which a surfactant or an alcohol is added.