Restoration method

Abstract

The present invention provides a reduction treatment method for efficiently generating the amount of hydrogen free radicals required for reduction through a relatively simple treatment process and reducing the surface of the object to be treated. In the reduction treatment method, a hydrogen free radical source-containing substance is irradiated with ultraviolet light having a wavelength of 255 nm or less to generate hydrogen free radicals, and the generated hydrogen free radicals are brought into contact with the surface of the object to be treated to reduce the surface.

Description

Technical Field

[0001] The present invention relates to a reduction treatment method. Background Art

[0002] The reduction reaction of the surface material of solid matter is used in various fields. For example, copper, which is widely used as a conductive material for electrodes, wiring, etc., forms an oxide film on the surface that causes poor conduction due to organic cleaning using oxygen plasma, ultraviolet light, and the passage of time in an atmosphere containing oxygen or water. And, a reduction reaction is used to remove the oxide film. In addition, in order to make the oxide film with the desired purpose such as a gate insulating film as an oxide film arranged on the surface of a semiconductor such as silicon or gallium nitride play its function, it is important to control the film thickness, film quality and shape of the oxide film. And, a reduction reaction is used in this control. In addition, in order to make the surface of a solid material such as a resin hydrophobic, a reduction reaction is used to remove oxygen atoms from hydrophilic groups such as hydroxyl groups and carboxyl groups present on the surface.

[0003] Examples of methods for reducing the surface of a solid substance include a method using carbon monoxide, a method using formic acid, a method using hydrogen, etc. Among them, the following documents are known as methods using hydrogen.

[0004] Patent Document 1 states that a gas mixed with Ar and hydrogen is plasma-formed to activate hydrogen, thereby reducing a copper oxide film. Patent Document 2 states that microwave surface wave hydrogen plasma is generated from hydrogen gas in a vacuum environment, thereby reducing and removing rust (oxide) of a processed object. Patent Document 3 states that a hydrogen-containing gas is plasma-formed to generate hydrogen radicals, thereby reducing and removing a metal compound film on a metal layer of a heated wafer.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: International Publication No. 2012 / 063474

[0008] Patent Document 2: Japanese Patent Application Publication No. 2006-307255

[0009] Patent Document 3: Japanese Patent Application Publication No. 2009-010043 Summary of the invention

[0010] Problems to be solved by the invention

[0011] It is known to use hydrogen radicals to reduce the surface of a workpiece. However, the methods for generating hydrogen radicals described in Patent Documents 1 to 3 involve the following problems.

[0012] As for the treatment methods described in Patent Documents 1 and 3, since high-frequency power is used to convert the gas containing hydrogen into plasma, the treatment process and the device structure are complicated. In addition, from the perspective of safety and the ignition property of plasma, the gas containing hydrogen is usually mixed with an inert gas such as Ar. In this way, the composition ratio of hydrogen is low, so there is a limit to the improvement of the reduction efficiency.

[0013] The treatment method described in Patent Document 2 is limited to treatment in a vacuum environment, and since microwaves are used, the treatment process and device configuration for achieving the treatment environment are complicated. In addition, it is difficult to efficiently generate a large amount of hydrogen radicals.

[0014] Based on the above problem awareness, an object of the present invention is to provide a reduction treatment method for reducing the surface of a treatment object by efficiently generating an amount of hydrogen radicals required for reduction treatment through a relatively simple treatment process.

[0015] Methods used to solve problems

[0016] The inventors have conducted intensive research and have found a method for efficiently generating an amount of hydrogen radicals capable of reducing the surface of a treated object without using plasma generated by high-frequency power or microwaves. The details will be described later. The method is a method for generating hydrogen radicals by irradiating an object containing a hydrogen radical source with ultraviolet light having a wavelength of 255 nm or less.

[0017] In the reduction treatment method of the present invention, a substance containing a hydrogen radical source is irradiated with ultraviolet light having a wavelength of 255 nm or less to generate hydrogen radicals, and the generated hydrogen radicals are brought into contact with the surface of the object to be treated to reduce the surface.

[0018] Compared with the method using plasma generated by high-frequency power or microwaves, the method of generating hydrogen radicals by irradiating ultraviolet light with a wavelength of 255 nm or less can simplify the treatment process and the device structure used for the treatment. In addition, the method of generating hydrogen radicals by irradiating ultraviolet light with a wavelength of 255 nm or less can generate the amount of hydrogen radicals required for the reduction treatment.

[0019] The expressions "reducing" and "reducing treatment" described in this specification are paired with "oxidizing" and "oxidizing treatment." In other words, "reduction" refers to a reaction of removing oxygen from a target substance, a reaction of donating hydrogen, or a reaction of donating electrons.

[0020] The hydrogen radical source may contain one or more substances belonging to the group consisting of hydrogen, hydrocarbons, H2O, alcohols, phenols, NH3, amines, H2S and mercaptans. These substances can generate a large amount of hydrogen radicals.

[0021] The hydrogen radical source-containing substance may contain ROH (R represents a hydrogen atom or an alkyl group).

[0022] The hydrogen radical source-containing substance may contain ROH (R represents an alkyl group having 3 to 10 carbon atoms). The ultraviolet light for such a material may be light having a wavelength of 205 nm or less.

[0023] In the reduction treatment method, the hydrogen radical source-containing substance can be brought into contact with the surface of the object to be treated, and the hydrogen radical source-containing substance in contact with the surface of the object to be treated can be irradiated with the ultraviolet light. Since a large number of hydrogen radicals can be generated at the same time, a large area can be reduced at the same time, so the treatment efficiency is high.

[0024] In the reduction treatment method, the hydrogen radical source-containing material may be irradiated with the ultraviolet light to generate hydrogen radicals, and the generated hydrogen radicals may be sprayed onto the surface of the object to be treated, so that the hydrogen radicals can be selectively supplied to the area requiring reduction treatment.

[0025] The above-mentioned object to be treated may have a metal or semiconductor oxide film on the surface, or may have a resin containing a hydrophilic group on the surface.

[0026] The ultraviolet light may be ultraviolet light generated by a xenon excimer lamp.

[0027] In the reduction treatment method, a material containing hydrogen atoms is brought into contact with the surface of the object to be treated, and the material in contact with the surface of the object to be treated is irradiated with ultraviolet light having a wavelength of 255 nm or less to reduce the surface of the object to be treated.

[0028] Effects of the Invention

[0029] Thus, it is possible to provide a reduction treatment method for efficiently generating a required amount of hydrogen radicals and reducing the surface of a treatment object through a simple treatment process. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a graph showing the absorption spectrum of light with respect to water.

[0031] Figure 2 It is a graph showing the absorption spectrum of light with respect to methanol.

[0032] Figure 3 It is a graph showing the absorption spectrum of light with respect to ethanol.

[0033] Figure 4 It is a diagram showing the absorption spectrum of light with respect to ammonia.

[0034] Figure 5 This is a diagram showing the absorption spectrum of light with respect to hydrogen sulfide.

[0035] Fig. 6A It is a diagram for explaining a first embodiment of the reduction treatment method.

[0036] Figure 6B It is a diagram for explaining a modified example of the first embodiment of the reduction treatment method.

[0037] Figure 7 It is a diagram for explaining a second embodiment of the reduction treatment method.

[0038] Figure 8 It is a diagram for explaining a third embodiment of the reduction treatment method.

[0039] Fig.9A This is a diagram showing the results of XPS analysis of a copper plate with an oxide film.

[0040] Fig. 9B This is a diagram showing the results of XPS analysis of a copper plate subjected to a reduction treatment.

[0041] Fig.10 This is a diagram showing the results of XPS analysis of a copper plate subjected to a reduction treatment. DETAILED DESCRIPTION

[0042] [Overview of restoration process]

[0043] First, the outline of the reduction treatment is described. As the light used in the reduction treatment, ultraviolet light with a wavelength of 255 nm or less is used.

[0044] The "ultraviolet light with a wavelength of 255 nm or less" used in this specification refers to light having a luminescence band below 255 nm. The light includes, for example: light showing a luminescence spectrum with a peak luminescence wavelength showing the maximum intensity below 255 nm in wide wavelength light, and light showing a luminescence spectrum with a luminescence wavelength showing two or more maximum intensities (two or more peaks), any one of the peaks of which is included in the wavelength range below 255 nm. In addition, light below 255 nm that shows an integrated intensity of at least 30% relative to the total integrated intensity in the luminescence spectrum is also included in the "ultraviolet light with a wavelength of 255 nm or less". It should be noted that the same definition applies to the case where the upper limit of the wavelength is a value other than 255 (nm).

[0045] The details will be described later, and even in ultraviolet light with a wavelength of less than 255nm (hereinafter, when simply referred to as "ultraviolet light", it means light with a wavelength of less than 255nm), there is a more preferred wavelength depending on the hydrogen radical source. In addition, regarding the type of light source used, for example, a xenon excimer lamp can be used to obtain light with a wavelength of 172nm, and the light source used can be selected according to the wavelength of the desired light.

[0046] The details of the hydrogen radical source used in the reduction treatment method will be described later. Here, representative substances used as the hydrogen radical source include hydrogen or hydrocarbon (RH), water or monohydric alcohol (ROH), hydrogen sulfide or mercaptan (RSH), ammonia, primary amine or secondary amine (R 1 R 2 NH)(R, R 1 or R 2 The following is a reaction formula for generating hydrogen radicals (H·) by irradiating these substances with ultraviolet light (UV).

[0047] RH+UV→R·+H·

[0048] ROH+UV→RO·+H·

[0049] RSH+UV→RS·+H·

[0050] R 1 R 2 NH+UV→R 1 R 2 N·+H·

[0051] The hydrogen radical source is irradiated with ultraviolet light (UV) to generate hydrogen radicals (H ). The generation reaction is carried out independently of pressure, so it is usually not necessary to make the reaction site a reduced pressure environment, and the reduction treatment can be carried out under an atmospheric pressure environment. In addition, the details will be described later, and the hydrogen radical source can be in any state of gas, liquid and solid. In addition, if the concentration of the hydrogen radical source is increased, the generation efficiency of the hydrogen radical is easily improved.

[0052] When the generated hydrogen radical (H·) contacts the surface of the object to be processed, the surface of the object to be processed is reduced. As mentioned above, the reduction treatment can be used for various purposes such as removing the oxide film formed on the surface of the conductive material, controlling the film thickness, film quality and shape of the gate oxide film, and hydrophobizing the surface of the solid material.

[0053] [Hydrogen radical source]

[0054] The hydrogen radical source is described in detail. The hydrogen radical source is a substance containing hydrogen atoms before being radicalized. In particular, substances containing one or more substances belonging to the group consisting of hydrogen (H2), hydrocarbons, H2O, alcohols, phenols, NH3, amines, H2S and thiols are suitable as hydrogen radical sources. The above substances can generate a large number of hydrogen radicals. Among the above, as hydrocarbons, the following can be used: methane (CH4), ethane (C2H6), propane (C3H8), alkane (C n H 2n+2 ); and olefins represented by ethylene (C2H4), propylene (C3H6), ... n H 2n ); and acetylene (C2H2), methylacetylene (C3H4), alkynes (C n H 2n-2 ) and the like. In the above, as alcohols, not only monohydric alcohols represented by methanol (CH3OH), ethanol (C2H5OH), ... can be used, but also polyhydric alcohols such as ethylene glycol and glycerol can be used. In the above, phenols are a general term for substances having OH groups bonded to aromatics. In the above, as amines, in addition to primary amines such as methylamine (CH3NH2), ethylamine (C2H7NH2), ..., secondary amines (such as dimethylamine ((CH3)2NH)) and tertiary amines (such as trimethylamine) can be used. In the above, as thiols, in addition to alkylthiols represented by methyl mercaptan (CH3SH), ethyl mercaptan (C2H5SH), ..., substances having SH groups bonded to aromatics such as thiophenol (C6H5SH) can be used.

[0055] Among the above hydrogen radical sources, water or monohydric alcohol (ROH, R is hydrogen or an alkyl group) can be preferably used in consideration of various factors such as safety, ease of handling, availability, and economy.

[0056] In the case of water or methanol or ethanol having hygroscopicity, water or monohydric alcohol generates OH radicals as oxidizing chemical species simultaneously with hydrogen radicals by irradiating the water contained in the hydrogen radical source with UV. OH radicals may hinder the reduction reaction. Thus, monohydric alcohols having 3 or more carbon atoms with low hygroscopicity generate less OH radicals accompanying UV irradiation and are particularly suitable for reduction treatment. Considering the simplicity of treatment, monohydric alcohols having 10 or less carbon atoms are more preferred.

[0057] Figure 1 to Figure 5 Each figure shows the absorption spectrum of ultraviolet light relative to the main source of hydrogen radicals. Figure 1 to Figure 5 In the graph, the horizontal axis represents the wavelength of ultraviolet light [nm], and the vertical axis represents the absorption cross section of light per molecule [cm] on a logarithmic scale. 2· Molecule-1]. Based on Figure 1 to Figure 5 Each figure explains the wavelength of ultraviolet light suitable for the reduction treatment of each hydrogen radical source.

[0058] Figure 1 The absorption spectrum of light relative to water (H2O) is shown. Figure 1 When water is used as the hydrogen radical source, it is effective to use light below 190 nm. Figure 2 The absorption spectrum relative to methanol (CH3OH) is shown. Figure 3 The absorption spectrum relative to ethanol (C2H5OH) is shown. Figure 2 and Figure 3 When various alcohols are used as the hydrogen radical source, it is effective to use light below 205 nm. Figure 4 The absorption spectrum relative to ammonia (NH3) is shown. Figure 4 When ammonia is used as the hydrogen radical source, it is effective to use light below 225 nm. Figure 5 The absorption spectrum relative to hydrogen sulfide (H2S) is shown. Figure 5 When hydrogen sulfide is used as the hydrogen radical source, it is effective to use light below 255 nm.

[0059] In the above, in the absorption spectrum of any hydrogen radical source, the absorption cross-sectional area of ​​light per molecule is approximately 1×10 -20 (cm 2 ·molecular -1 ) or above. This is because the inventors have conducted in-depth research and found that regardless of the type of hydrogen radical source, the light absorption cross-sectional area of ​​each molecule is 1×10 -20 (cm 2 ·molecular -1 ) or above has the ability to absorb hydrogen radicals used for reduction treatment efficiently from the hydrogen radical source. It is more preferred that the absorption cross-sectional area of ​​light per molecule is 1×10 -19 (cm 2 ·molecular -1 ) The wavelength is set in the above manner. However, the preferred wavelength range for efficiently generating hydrogen radicals varies not only due to the absorption cross-sectional area of ​​light per molecule, but also due to the concentration of the hydrogen radical source in the hydrogen radical source-containing material and the distance between the light source and the object to be processed.

[0060] [Object to be processed]

[0061] As the object to be processed, for example, a metal or semiconductor having an oxide film on the surface can be cited. The oxide film on the surface is removed by a reduction reaction. In addition, the object to be processed can also be a material such as a resin having hydrophilic groups such as hydroxyl and carboxyl groups on the surface. The surface of the material is hydrophobized by removing the oxygen atoms in the hydrophilic group by a reduction reaction. It should be noted that the shape of the object to be processed is not limited to a plate-like object, and can also be composed of a shape with thickness or a shape with a three-dimensional structure.

[0062] <First embodiment>

[0063] An embodiment of the reduction treatment method is described with reference to the accompanying drawings. It should be noted that the drawings disclosed in this specification are only schematic drawings. That is, the dimension ratios on the drawings may not be consistent with the actual dimension ratios, and the dimension ratios between the drawings may not be consistent.

[0064] refer to Fig. 6A A first embodiment of the reduction treatment method is described. A workpiece 4 having an oxide on its surface is placed on a stage 3 of a treatment chamber 2 having a light source 1 (shadow area) emitting ultraviolet light inside. Then, a gas G1 containing a hydrogen radical source (for example, a gas obtained by adding an inactive gas such as nitrogen or a rare gas to a gas serving as a hydrogen radical source) is supplied from an inlet-side piping 8 connected to the treatment chamber 2, and an atmospheric gas G2 in the treatment chamber 2 is discharged from an outlet-side piping 9, and the inside of the treatment chamber 2 is replaced (purged) with the gas G1.

[0065] After the processing chamber 2 is purged with gas G1, ultraviolet light L1 (dashed arrow in the figure) is emitted to excite the hydrogen radical source contained in the gas G1 in the processing chamber 2 to generate hydrogen radicals (H·). The generated hydrogen radicals (H·) come into contact with the oxide on the surface of the processed object 4 to undergo a reduction reaction.

[0066] In this embodiment, since a relatively wide range of reduction treatment can be performed simultaneously, the surface reduction of a large area of ​​the object 4 can be treated in a short time. In addition, since hydrogen radicals are generated near the object 4, the utilization efficiency of the generated hydrogen radicals is high.

[0067] Regarding the arrangement of the object 4, since the ultraviolet light L1 is absorbed by the gas G1, in order to make the ultraviolet light L1 generate hydrogen radicals near the object, the object 4 is arranged in a manner not too far away from the light source 1. In addition, if the object 4 is too close to the light source 1, the amount of the hydrogen radical source that absorbs the light is reduced, so the object 4 is arranged in a manner not too close to the light source 1. That is, the object 4 is separated from the light source 1 to such an extent that hydrogen radicals are generated by the ultraviolet light L1 and the generated hydrogen radicals can contact the surface of the object 4.

[0068] During the reduction treatment, the gas G1 can be continuously supplied to the processing chamber 2 and the ultraviolet light L1 can be emitted while the inlet-side piping 8 and the processing chamber 2 and the outlet-side piping 9 are connected to the processing chamber 2, or the ultraviolet light L1 can be emitted while the supply of gas G1 is stopped by isolating the inlet-side piping 8 and the processing chamber 2 and the outlet-side piping 9 and the processing chamber 2 by valves etc.

[0069] Figure 6B Show Fig. 6A A modified example of the invention. Two objects to be processed (4a, 4b) are arranged with the light source 1 sandwiched between them. Figure 6B In the embodiment, the two processed objects (4a, 4b) are arranged at equal distances from the light source 1, thereby achieving uniform reduction processing speed. It should be noted that the two processed objects (4a, 4b) may not be arranged at equal distances from the light source 1.

[0070] <Second embodiment>

[0071] refer to Figure 7 A second embodiment of the reduction treatment method will be described. Matters other than the following description can be implemented in the same manner as the first embodiment. Figure 7 In the process, a liquid 5 containing a hydrogen radical source (hereinafter sometimes referred to as "hydrogen radical source liquid 5") is supplied in a manner to cover the object 4. For example, when the substance containing the hydrogen radical source is a liquid at normal temperature and pressure, the liquid (hydrogen radical source liquid 5) is injected into the object 4 to wet the surface of the object 4, or a liquid film composed of the hydrogen radical source liquid 5 is formed on the object 4. The hydrogen radical source liquid 5 is supplied in a manner to fill the space between the object 4 and the light source 1. The hydrogen radical source liquid 5 can be supplied to the object 4 from a supply nozzle not shown in the figure before the light source 1 is turned on in the treatment chamber 2. Alternatively, the hydrogen radical source liquid 5 can be supplied to the object 4 outside the treatment chamber 2 and the wetted (or liquid film-formed) object 4 can be moved into the treatment chamber 2. Here, the treatment chamber 2 is preferably filled with an inert gas such as nitrogen or a rare gas as an atmosphere gas.

[0072] The hydrogen radical source-containing substance may also be a solid. When the hydrogen radical source-containing substance is a solid at room temperature and pressure, the solid of the hydrogen radical source-containing substance may be arranged on the treated object 4. However, it is required to be a solid thinner than the thickness at which the ultraviolet light can reach the interface between the treated object 4 and the solid. In addition, when the hydrogen radical source-containing substance is more preferably a solid than a gas or a liquid, the hydrogen radical source-containing substance may be solidified by making the liquid treated object 4 at a low temperature.

[0073] <Third embodiment>

[0074] A third embodiment of the reduction treatment method will be described with reference to the accompanying drawings. Matters other than the following description can be implemented in the same manner as the first and second embodiments. Figure 8 In the embodiment, the gas G3 containing a hydrogen radical source passing through the pipe 6 is irradiated with ultraviolet light L1 from a light source 1 disposed outside the pipe 6 through which the gas G3 containing a hydrogen radical source flows, so that the gas G3 containing a hydrogen radical source is excited to generate hydrogen radicals (H·). Then, the gas containing hydrogen radicals (H·) is sprayed from the front end 7 of the pipe 6 toward the surface of the object 4 to be processed. When the hydrogen radicals come into contact with the oxide on the surface of the object 4 to be processed, a reduction reaction is performed. In the present embodiment, by moving the object 4 to be processed and the front end 7 of the pipe 6 relative to each other while maintaining the interval between the object 4 to be processed and the front end 7, it is possible to selectively process only the area that requires reduction treatment. In addition, in the present embodiment, it is not necessary to purge the processing space with the gas containing a hydrogen radical source.

[0075] In the present embodiment, the light source 1 is sandwiched between two or more pipes 6, but is not limited to this configuration. For example, the light source 1 may be inserted into the center of a pipe without contacting the inner wall of the pipe, or two or more light sources may surround one or more pipes. In addition, in the present embodiment, the light source 1 is arranged near the front end 7 of the pipe 6, but the light source 1 may also be arranged at the pipe 6 away from the front end 7. This embodiment can be used when the hydrogen radical source contains a fluid.

[0076] The first embodiment, the second embodiment and the third embodiment are described above. However, the present invention is not limited by the above embodiments, and various changes or improvements can be made to the above embodiments within the scope of the gist of the present invention. In addition, the first embodiment and the third embodiment can be combined to irradiate the above hydrogen radical source with the above ultraviolet light before contacting the surface of the object to be processed and irradiate the above ultraviolet light after the hydrogen radical source is contacted with the surface of the object to be processed. Thus, the generation efficiency of hydrogen radicals can be improved.

[0077] Example 1

[0078] A copper plate having an oxide film on its surface is prepared. The copper plate having an oxide film on its surface is referred to as a copper plate with an oxide film. Fig.9A The results of X-ray photoelectron spectroscopy (XPS) analysis of a copper plate with an oxide film are shown. The horizontal axis represents the binding energy of photoelectrons, and the vertical axis represents the relative value of the photoelectron intensity. Fig.9AIn the graph, the first peak P1 is observed near the binding energy of 935 eV, and the broad second peak P2 is observed near the binding energy of 940-945 eV. The first peak P1 indicates the presence of CuO with a binding energy of 933.8 eV (or Cu2O with a binding energy of 932.5 eV), and the second peak P2 indicates the satellite peak of CuO. Fig.9A It can be seen that a copper oxide film is detected on the surface.

[0079] Prepare 20 mL of IPA (isopropyl alcohol) as a hydrogen radical source. Place the copper plate with an oxide film at a distance of 2 mm from the light source in the first embodiment ( Fig. 6A ) is introduced into the processing chamber 2 shown in the figure, nitrogen gas is introduced into the prepared IPA at 1 L / min and bubbled, and the nitrogen gas containing IPA obtained thereby is introduced into the processing chamber 2.

[0080] When the processing chamber 2 is purged with nitrogen containing IPA, the light source (mainly emitting light with a wavelength of 172 nm and a radiation intensity of 30 mW / cm 2 The xenon excimer lamp of the present invention is lit for 15 minutes to perform reduction treatment on the copper plate with oxide film. In this embodiment, during the reduction treatment, nitrogen gas containing IPA is continuously introduced into the treatment chamber 2.

[0081] The results of XPS analysis of the copper plate after the reduction treatment are shown in FIG. Fig. 9B middle. Fig.9A The peaks (P1 and P2) indicating the presence of CuO and Cu2O that appeared in the graphene disappeared, and the third peak P3 (binding energy of 932.7 eV) indicating the presence of Cu was confirmed. Therefore, it was confirmed that the copper oxide was reduced to copper by the reduction treatment.

[0082] Example 2

[0083] Nitrogen gas containing ethanol instead of IPA was introduced into the same treatment chamber as in Example 1, and the reduction treatment of the copper plate with oxide film was performed in the same manner as in Example 1. Other treatment conditions were the same as in Example 1.

[0084] The results of XPS analysis of the copper plate after the reduction treatment are shown in FIG. Fig.10 middle. Fig.9A The peaks (P1 and P2) indicating the presence of CuO and Cu2O that appeared in the graph disappeared, and the third peak P3 (binding energy of 932.7 eV) indicating the presence of Cu was confirmed. Therefore, it was confirmed that copper oxide was reduced to copper due to hydrogen radicals formed by irradiating the ethanol gas with the light emitted from the light source 1.

[0085] Explanation of symbols

[0086] 1: Light source

[0087] 2: Processing room

[0088] 3: Stage

[0089] 4: Object to be processed

[0090] 5: Hydrogen free radical source liquid

[0091] 6: Piping

[0092] 7: Front-end

[0093] 8: Inlet side piping

[0094] 9: Outlet side piping

[0095] G1: Gas containing a source of hydrogen radicals

[0096] G2: Atmosphere gas in the treatment room

[0097] G3: Gas containing a source of hydrogen radicals

[0098] L1: Ultraviolet light

[0099] P1: First Peak

[0100] P2: Second Peak

[0101] P3: The third peak

Claims

1. A reduction treatment method, characterized in that: The alcohol-containing hydrogen radical source is irradiated with ultraviolet light having a wavelength of 205 nm or less to generate hydrogen radicals, and the generated hydrogen radicals are brought into contact with the surface of the object to be treated to reduce the surface, wherein the ultraviolet light having a wavelength of 205 nm or less is a light having an absorption cross-sectional area of ​​1×10 -20 (cm 2 ·molecular -1 ) or above wavelength.

2. The reduction treatment method according to claim 1, characterized in that: The hydrogen radical source-containing substance contains ROH, wherein R represents an alkyl group having 3 or more and 10 or less carbon atoms.

3. The reduction treatment method according to claim 1 or 2, characterized in that: bringing the hydrogen radical source-containing substance into contact with the surface of the object to be treated, The ultraviolet light is irradiated onto the hydrogen radical source-containing material in contact with the surface of the object to be processed.

4. The reduction treatment method according to claim 1 or 2, characterized in that: irradiating the substance containing the hydrogen radical source with the ultraviolet light to generate hydrogen radicals, The generated hydrogen radicals are sprayed onto the surface of the object to be processed.

5. The reduction treatment method according to claim 1 or 2, characterized in that: The object to be processed has a metal or semiconductor oxide film on the surface.

6. The reduction treatment method according to claim 1 or 2, characterized in that: The object to be treated has a resin containing a hydrophilic group on its surface.

7. The reduction treatment method according to claim 1 or 2, characterized in that: The ultraviolet light is ultraviolet light generated by a xenon excimer lamp.

8. A reduction treatment method, characterized in that: The alcohol-containing material is brought into contact with the surface of the object to be treated. The material in contact with the surface of the object to be treated is irradiated with ultraviolet light having a wavelength of 205 nm or less to reduce the surface of the object to be treated, wherein the ultraviolet light having a wavelength of 205 nm or less is further reduced by an absorption cross-sectional area of ​​1×10 -20 (cm 2 ·molecular -1 ) or above wavelength.

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