JP2011029148A - Post-treatment method and deposition/post-treatment device for conductive metal oxide - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve electrical characteristic of a conductive metal oxide film containing carbon. <P>SOLUTION: An oxidizing post-treatment step is executed by bringing the oxidizing gas having an oxidizing effect come into contact with the conductive metal oxide film 92 after the conductive metal oxide containing carbon is deposited. Preferably, the oxidizing effect is performed or accelerated by heating the conductive metal oxide film 92 or activating the oxidizing gas. A reduction post-treatment step is executed by bringing the reduction gas having a reduction effect come into contact with the conductive metal oxide film 92 after the oxidizing post-treatment step. Preferably, the reduction effect is performed or accelerated by heating the conductive metal oxide film 92 or activating the reduction gas. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a post-processing method and a film-forming / post-processing apparatus performed on a conductive metal oxide after film formation, and in particular, using a raw material containing an organometallic compound, a CVD (Chemical Vapor Deposition) method, a spray method, a sol-gel. The present invention relates to a post-processing method and a film forming / post-processing apparatus suitable for a crystalline conductive metal oxide formed by a method or the like.

  Conductive metal oxides are also used as materials for antistatic coatings, including transparent electrodes for flat panel displays and transparent electrodes for solar cells, and the demand is increasing year by year. As typical conductive metal oxides, ITO (Indium Tin Oxide), zinc oxide, tin oxide, titanium oxide, and the like are known. This type of conductive metal oxide is crystalline. A crystalline metal oxide has an arrangement in which atoms and molecules have a spatially repeated pattern, and generally acts as a diffraction grating for light having a wavelength of about X-rays, causing a phenomenon called X-ray diffraction. .

  The method for forming a conductive metal oxide is roughly classified into a physical film formation method using a physical action such as collision or vapor deposition, and a chemical film formation method using a chemical reaction. Examples of the physical film forming method include sputtering under vacuum and vacuum deposition. In these physical film forming methods, a sintered body of high-purity metal oxide is generally used as a film forming raw material. Examples of the chemical film forming method include a CVD method, a spray method, and a sol-gel method. In these chemical film forming methods, an organometallic compound is generally used as a film forming raw material.

  Conductive metal oxides may require post-treatment to improve electrical characteristics and workability after film formation. As post-treatments for improving electrical characteristics, reducing treatments and heat treatments are often used. As examples of reducing post-treatment aimed at lowering electrical resistivity by increasing oxygen vacancies, heat treatment in a hydrogen atmosphere of Non-Patent Document 1 and hydrogen plasma treatment of Patent Document 1 are known. ing. Patent Document 2 is an example of heat treatment aiming at a decrease in electrical resistivity due to an increase in the mobility of carrier electrons in the conductive thin film. Patent Document 3 is an example of heat treatment aimed at lowering electrical resistivity by suppressing oxygen adsorption to the conductive thin film. Patent Document 4 is an example of heat treatment aimed at lowering electrical resistivity by improving the crystallinity of the conductive thin film.

JP 2007-77456 A JP-A 63-170813 JP 2008-53118 A Japanese Patent Laid-Open No. 3-84816

Mie Prefectural Science and Technology Promotion Center Industrial Research Department Research Report No. 32 (2008)

A physical film formation method such as sputtering or vacuum evaporation uses a sintered body of high-purity metal oxide as a raw material, and thus the production cost of the conductive metal oxide thin film is high.
On the other hand, chemical film formation methods such as CVD, spraying, and sol-gel methods use an organometallic compound as a raw material, so that the production cost of the conductive metal oxide thin film can be reduced. However, since an organic metal compound is used as a raw material, organic impurities caused by the carbon component in the raw material are easily taken into the film surface or crystal grain boundaries. Such organic impurities serve as a barrier for conduction and cause an increase in the electrical resistivity of the film. This type of organic impurity is difficult to remove sufficiently only by the reducing post-treatment described above. In the case of heat treatment, if the treatment temperature is increased to a temperature at which organic impurities are removed (for example, about 700 ° C.), the film structure may be disturbed due to the difference in expansion coefficient between the film and the substrate, and the electrical resistivity may increase. is there.
In view of such circumstances, the present invention provides a post-treatment method that can reliably improve the electrical characteristics of a conductive metal oxide containing carbon.

Conventionally, when a conductive metal oxide film is post-treated in an oxidizing atmosphere, oxygen is adsorbed on the surface of the conductive metal oxide film or at the crystal grain boundary, and this adsorbed oxygen acts as a barrier for carrier electron transfer to cause electricity. It was thought to increase resistivity. Therefore, for the purpose of reducing the electrical resistivity, it has been considered desirable to perform post-treatment in a non-oxidizing atmosphere or an inert atmosphere.
However, the inventor removed the carbon component present on the surface of the conductive metal oxide film and the crystal grain boundary without raising the temperature to a temperature that induces disorder of the film structure by the treatment in an oxidizing atmosphere. It was found that this can be done (see Example 1 below). Furthermore, it has been found that the oxidative post-treatment can oxidize a metal-hydroxyl conjugate contained in the conductive metal oxide film to reduce the hydroxyl group concentration in the conductive metal oxide film (Example 1 described later). And FIG. 5).

The present invention has been made on the basis of such findings, and is a post-treatment method performed on the conductive metal oxide film after forming the conductive metal oxide containing carbon.
An oxidizing post-treatment step in which an oxidizing gas having an oxidizing action is brought into contact with the conductive metal oxide film;
A reducing post-treatment step of bringing a reducing gas having a reducing action into contact with the conductive metal oxide film after the oxidizing post-treatment step;
It is characterized by including.

The first action of removing organic impurities mainly composed of carbon at the surface of the conductive metal oxide film or at the grain boundary by the oxidizing post-treatment step, and the metal and hydroxyl group contained in the conductive metal oxide film The second effect of reducing the concentration of hydroxyl groups in the conductive metal oxide film by oxidizing the combined body can be achieved. The first effect can be achieved at a relatively low temperature without raising the temperature to a temperature (for example, about 700 ° C.) that induces disturbance of the film structure. By the first and second actions, the number of carrier electron capture sites in the conductive metal oxide film can be reduced, and the mobility of carrier electrons can be increased. By performing the reducing post-treatment step subsequent to the oxidizing post-treatment step, the surface of the conductive metal oxide film can be stabilized, and even if the conductive metal oxide film is exposed to the atmosphere, It is possible to prevent moisture from entering the surface of the conductive metal oxide film and crystal grain boundaries, and to prevent the invading oxygen and moisture from becoming a carrier electron capture site. Furthermore, oxygen vacancies having carrier electrons can be increased by reducing post-treatment.
As a result, the electrical resistivity of the conductive metal oxide film can be reduced. Furthermore, an increase in electrical resistivity of the conductive metal oxide film with time can be reduced.

  The conductive metal oxide is preferably subjected to the oxidative post-treatment step without being exposed to the air after film formation. Thereby, it can prevent that components other than oxygen including the water | moisture content in air | atmosphere touch an electroconductive metal oxide, and raise | generate an inappropriate reaction. Alternatively, oxygen in the atmosphere can be prevented from coming into contact with the conductive metal oxide to form an incomplete oxide film, and the subsequent oxidative post-treatment can be prevented from being inhibited. A conductive metal oxide film is formed on the surface of the substrate while heating the substrate with a heating means, and then continues to be heated by the residual heat at the time of film formation or after the film formation is completed until after the oxidizing post-treatment. Thus, moisture in the atmosphere may be prevented from adhering to the conductive metal oxide.

  Preferably, in the oxidizing post-treatment step, the oxidizing gas is activated by one activating means selected from the group consisting of plasma generating means, microwave irradiating means, and ultraviolet irradiating means, or the conductive metal oxide Heat the membrane. Thereby, the oxidation action can be surely caused. Only one of activation of the oxidizing gas and heating of the conductive metal oxide film may be performed. More preferably, both the activation of the oxidizing gas and the heating of the conductive metal oxide film are performed simultaneously.

The plasma generating means in the oxidizing post-processing step is activated by converting the oxidizing gas into plasma. For example, the plasma generating means has at least a pair of electrodes, applies an electric field between these electrodes to generate a discharge, and introduces an oxidizing gas between the electrodes to generate plasma. Plasmaization is preferably performed near atmospheric pressure. Here, the vicinity of atmospheric pressure refers to a range of 1.013 × 10 ⁴ Pa to 50.663 × 10 ⁴ Pa, and considering the ease of pressure adjustment and the simplification of the apparatus configuration, 1.333 × 10 ^4. Pa~10.664 × ¹⁰ 4 Pa, and more preferably still ^{9.331 × 10 4 Pa~10.397 × 10 4} Pa in the oxidative post-treatment step and the reducing post-treatment step. The film-forming step, and more preferably ^{5 × 10 4 Pa~10.397 × 10 4} Pa.
The microwave irradiation means in the oxidizing post-treatment step is activated by irradiating the oxidizing gas with microwaves.
The ultraviolet irradiation means in the oxidizing post-treatment step is activated by irradiating the oxidizing gas with ultraviolet rays. For example, when the oxidizing gas is an oxygen-containing gas, oxygen is ozonized (activated) by ultraviolet irradiation.
The heating temperature of the conductive metal oxide film in the oxidative post-treatment step is less than the temperature that induces disorder of the film structure, preferably about 100 ° C. to 300 ° C., more preferably 200 ° C. to 300 ° C. Degree. Since the conductive metal oxide is usually formed on the surface of a substrate such as glass or a semiconductor wafer, the conductive metal oxide film may be heated by heating the substrate.

The oxidizing gas contains oxygen (O ₂ ), nitrous oxide (N ₂ O), and other oxygen-containing compounds as an oxidizing component, and preferably contains oxygen (O ₂ ). The concentration of the oxidizing component such as oxygen in the oxidizing gas may be a trace amount, but is preferably 5% by volume or more, more preferably 50% by volume or more, and still more preferably 70% by volume or more. The oxidizing gas may be composed of 100% oxidizing components such as oxygen. When the concentration of an oxidizing component such as oxygen in the oxidizing gas is less than 100%, the remainder of the oxidizing gas is preferably an inert gas. Examples of the inert gas include nitrogen, argon, helium and the like. Part or all of oxygen (O ₂ ) of the oxidizing gas may be activated by the activating means to become ozone, oxygen plasma, or oxygen radical.

  The conductive metal oxide is preferably subjected to the reducing post-treatment step without being exposed to the air after the oxidizing post-treatment step. Thereby, it can prevent that the water | moisture content in air | atmosphere contacts an electroconductive metal oxide, and raise | generates an inappropriate reaction. It may be possible to prevent moisture in the atmosphere from adhering to the conductive metal oxide by continuing to heat the conductive metal oxide after the oxidizing post-treatment until the reducing post-treatment.

  Preferably, in the reducing post-treatment step, the reducing gas is activated by one activating means selected from the group consisting of plasmaizing means, microwave irradiating means, and ultraviolet irradiating means, or the conductive metal oxide Heat the membrane. Thereby, the reduction action can be surely caused. Only one of activation of the reducing gas and heating of the conductive metal oxide film may be performed. Both the activation of the reducing gas and the heating of the conductive metal oxide film may be performed simultaneously.

The plasma generating means in the reducing post-treatment step activates the reducing gas by converting it into plasma. For example, the plasma generating means has at least a pair of electrodes, generates an electric discharge by applying an electric field between these electrodes, and introduces a reducing gas between the electrodes to generate plasma. Plasma conversion is preferably performed under atmospheric pressure in the same manner as in the oxidizing post-treatment step.
The microwave irradiation means in the reducing post-treatment step is activated by irradiating the reducing gas with microwaves.
The ultraviolet irradiation means in the reducing post-treatment step is activated by irradiating the reducing gas with ultraviolet rays.
The heating temperature of the conductive metal oxide film in the reducing post-treatment step is preferably about 200 ° C to 500 ° C. By performing the oxidizing post-treatment step prior to the reducing post-treatment step, the heating temperature of the conductive metal oxide film in the reducing post-treatment step can be lowered. Also in the reducing post-treatment step, the conductive metal oxide film may be heated by heating the substrate on which the conductive metal oxide is to be coated, as in the oxidizing post-treatment step.

The reducing gas preferably contains reducing components such as hydrogen (H ₂ ), carbon monoxide (CO), hydrogen sulfide (H ₂ S), sulfur oxide (SOx), and formaldehyde. More preferably, the reducing gas contains hydrogen (H ₂ ). The concentration of the reducing component such as hydrogen in the reducing gas is preferably 0.5% by volume or more, more preferably 1% by volume or more, and the upper limit concentration is 100%. When the reducing component is hydrogen, from the viewpoint of safety, the upper limit of the hydrogen concentration in the reducing gas is preferably about 10% by volume, more preferably about 5% by volume. Moreover, it is preferable that reducing gas does not contain oxygen. Furthermore, it is preferable that oxygen does not exist in the processing space where the substrate to be deposited is placed. When oxygen can be completely excluded by replacing the treatment space with nitrogen or the like, the reducing gas may be composed of 100% hydrogen. When the concentration of a reducing component such as hydrogen in the reducing gas is less than 100%, the remainder of the reducing gas excluding the reducing component is preferably an inert gas such as nitrogen, argon, or helium.

  The conductive metal oxide is preferably crystalline and is an oxide of one or more metals selected from indium, zinc, titanium, tin, cadmium, gallium, aluminum, and antimony.

The conductive metal oxide is formed using a raw material containing an organometallic compound, for example. In that case, the conductive metal oxide includes carbon derived from an organometallic compound. Examples of the film forming method include a CVD method, a spray method, and a sol-gel method. The CVD method includes plasma CVD and thermal CVD.
Examples of the organometallic compound include zinc acetylacetonate [Zn (CH ₂ COCH ₂ COCH ₃ ) ₂ ; Zn (acac) ₂ ], gallium acetylacetonate [Ga (acac) ₃ ], and the like.

The film formation and post-treatment apparatus according to the present invention is an apparatus for forming a conductive metal oxide containing carbon and performing post-treatment after film formation,
(A) a support for supporting the substrate in the processing space;
(B) Plasmaizing means including an electrode that forms a plasma space that is the same as or continuous with the processing space;
(C) heating means for heating the substrate;
(D) A film forming gas containing the conductive metal oxide raw material, an oxidizing gas having an oxidizing action on the conductive metal oxide film, and a reducing action on the conductive metal oxide film A gas supply system that selects one of the reducing gases, supplies the plasma space, and supplies the processing space;
And the selection by the gas supply system is performed in the order of the film forming gas, the oxidizing gas, and the reducing gas.
Thereby, the film-forming process, the oxidizing post-treatment process, and the reducing post-treatment process can be performed sequentially and continuously using a common processing apparatus. As a result, a conductive metal oxide can be formed on the substrate, and further, the conductivity of the formed conductive metal oxide film can be increased. The substrate can be transferred from the film forming step to the oxidative post-treatment step and can be transferred from the oxidative post-treatment step to the reductive post-treatment step while the substrate is supported by the support portion and disposed in the processing space. Therefore, it is possible to easily prevent the conductive metal oxide film from being exposed to the atmosphere during the process transition, and to reliably prevent the oxidative post-treatment and the reductive post-treatment from being hindered.

The pressure of the plasma space and the processing space is preferably near atmospheric pressure.
By supplying a voltage to the electrode and operating the plasma generating means, the selected processing gas (film forming gas, oxidizing gas, or reducing gas) can be converted into plasma in a plasma space, and plasma processing is performed. The film forming step, the oxidizing post-processing step, or the reducing post-processing step can be executed. In parallel with the operation of the plasmarization means, the heating means may also be operated.
The operation of the plasmarizing unit may be stopped and the heating unit may be operated. Thereby, the film-forming process by heat processing, an oxidizing post-process, or a reducing post-process can be performed.

  According to the present invention, even when the conductive metal oxide contains carbon at the time of film formation, the electrical characteristics can be reliably improved.

It is a commentary front view showing a schematic structure of a processing device concerning one embodiment of the present invention in an execution state of a film formation process. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory front view showing a schematic configuration of a processing apparatus according to an embodiment of the present invention in an implementation state of an oxidizing post-treatment process. It is the explanation front view which shows the schematic structure of the processing apparatus which concerns on one Embodiment of this invention in the implementation state of a reducing post-process. It is the spectrum figure which showed the measurement result by the X ray diffraction method of the film | membrane after a film-forming process, and expanded the peak of the (002) plane in zinc oxide. It is the spectrum figure which showed the measurement result by X-ray photoelectron spectroscopy, and expanded the peak derived from the 1s orbital of oxygen, (a) shows after a film-forming process (unoxidized post-treatment), and (b) After oxidative post-treatment.

Hereinafter, an embodiment of the present invention will be described.
In the present invention, a conductive metal oxide is formed, and then the conductive metal oxide film is subjected to post-treatment for improving characteristics. The post-treatment includes an oxidative post-treatment step and a reducing post-treatment step. As shown in FIGS. 1 to 3, in this embodiment, the film forming process and the post-process are continuously performed using a common processing apparatus 1.

The conductive metal oxide film 92 (the phantom line in FIG. 1) is formed on the surface of the substrate 91 using an organometallic compound as a raw material. In this embodiment, for example, a zinc oxide film containing gallium is formed as the conductive metal oxide film 92. For example, zinc acetylacetonate [Zn (acac) ₂ ] is used as the zinc-containing organometallic compound that becomes the zinc source of the film 92. As the gallium-containing organometallic compound that becomes the gallium source of the film 92, for example, gallium acetylacetonate [Ga (acac) ₃ ] is used. Zinc acetylacetonate and gallium acetylacetonate are liquid at normal temperature and pressure.

As shown in FIG. 1, the film forming and post-processing apparatus 1 includes a processing unit 10 and a gas supply system 20. The processing unit 10 includes a chamber 19 and a pair of electrodes 11 and 12. The electrodes 11 and 12 are accommodated in the chamber 19. The pair of electrodes 11 and 12 has a parallel plate type electrode structure which is vertically opposed. A solid dielectric layer (not shown) is formed on the opposing surface of at least one of the electrodes 11 and 12. One (for example, the upper side) electrode 11 is connected to the power source 13. The other (eg, the lower) electrode 12 is electrically grounded. By supplying voltage from the power supply 13, the processing space 14 between the electrodes 11 and 12 becomes a plasma space near atmospheric pressure.
The processing unit 10 constitutes a plasma generating means or an activating means.

  A workpiece 90 is arranged in the processing space 14. The object 90 includes a substrate 91. A conductive metal oxide film 92 is formed on the upper surface of the substrate 91. The substrate 91 is made of, for example, a glass plate. A substrate 91 is placed on the lower electrode 12. The lower electrode 12 also serves as a substrate support portion. A heating means 15 is thermally connected to the electrode 12. The heating means 15 may be an electric heater or a temperature control medium path formed in the electrode 12. The substrate 91 is heated via the electrode 12 by the heating means 15.

  As shown in FIGS. 1 to 3, the gas supply system 20 of the film forming and post-processing apparatus 1 includes gas sources 21 to 25 and a gas supply path 28. The tip of the gas supply path 28 is connected to one end of the processing space 14 (the right end in FIG. 1). An exhaust passage 29 extends from the other end (the left end in FIG. 1) of the processing space 14.

  Gas sources 21 to 25 corresponding to processing steps are selectively connected to the gas supply path 28. As shown in FIG. 1, in the film forming process, the organometallic compound sources 21 and 22, the inert gas source 23, and the oxygen gas source 24 are connected to the gas supply path 28. As shown in FIG. 2, in the oxidizing post-treatment process, an inert gas source 23 and an oxygen gas source 24 (oxidizing component source) are connected to a gas supply path 28. As shown in FIG. 3, in the reducing post-treatment process, the inert gas source 23 and the reducing component source 25 are connected to the gas supply path 28. The gas supply system 20 selectively supplies a processing gas corresponding to the processing step to the processing space 14 (plasma space).

  In FIG. 1, the two organometallic compound sources 21 and 22 are each configured by a vaporizer. The vaporizer 21 stores liquid zinc acetylacetonate as a zinc raw material for the conductive metal oxide film 92. The vaporizer 22 stores liquid gallium acetylacetonate as a gallium raw material for the conductive metal oxide film 92.

The inert gas source 23 stores nitrogen (N ₂ ) as an inert gas. The gas of the inert gas source 23 serves as a carrier gas, a dilution gas, a plasma generation gas, or the like.
As shown in FIGS. 1 and 2, 100% oxygen gas (O ₂ ) is stored in the oxygen gas source 24.

As shown in FIG. 3, hydrogen gas (H ₂ ) is stored in the reducing component source 25 as a reducing component. In FIG. 3, instead of storing the nitrogen of the inert gas source 23 and the hydrogen of the reducing component source 25 separately, a mixed gas obtained by mixing nitrogen and hydrogen at a predetermined mixing ratio is used as one reducing gas source. You may store it. The volume mixing ratio of nitrogen and hydrogen is preferably N ₂ : H ₂ = 99.5: 0.5 to 90:10, more preferably N ₂ : H ₂ = 99: 1 to 95: 5.

The processing method by the processing apparatus 1 having the above configuration will be described in detail.
[Film formation process]
As shown in FIG. 1, a glass substrate 91 on which a conductive metal oxide film 92 is to be formed is placed on the electrode / substrate support portion 12. The temperature of the substrate 91 is adjusted to about 100 ° C. to 300 ° C. by the heating means 15.

In the film forming process, the two vaporizers 21 and 22 are connected to the gas supply path 28. Further, the inert gas source 23 and the oxygen gas source 24 are connected to the gas supply path 28. Oxygen (O ₂ ) from the oxygen gas source 24 in the film forming process becomes an oxygen source for the conductive metal oxide film 92 to be formed.

Nitrogen from the inert gas source 23 and oxygen from the oxygen gas source 24 are mixed and sent to the gas supply path 28. The oxygen content in the mixed gas (N ₂ + O ₂ ) is, for example, about O ₂ / N ₂ = 60 to 95 vol% with respect to nitrogen.

The mixed gas (N ₂ + O ₂ ) is used as a carrier gas, and the zinc raw material liquid (zinc acetylacetonate) is vaporized in the carrier gas in the vaporizer 21. In the vaporization method, a carrier gas (N ₂ + O ₂ ) is introduced into a space above the liquid level of the zinc raw material liquid in the vaporizer 21, and the saturated zinc raw material vapor existing in the space above the liquid level is transferred to the carrier gas. Extrusion while mixing with (N ₂ + O ₂ ). Instead of the extrusion method, a method of bubbling a carrier gas (N ₂ + O ₂ ) into the zinc raw material liquid in the vaporizer 21 may be adopted. The zinc raw material liquid may be heated to promote evaporation, and extrusion and heating, or bubbling and heating may be used in combination.

In the vaporizer 22, the carrier gas (N ₂ + O ₂ ) vaporizes a gallium raw material liquid (gallium acetylacetonate). The vaporization method is the same as that for the zinc raw material. Thereby, a film forming gas containing an organometallic compound (Zn (acac) ₂ and Ga (acac) ₃ ) is generated.

The film forming gas is introduced into the processing space 14 from the gas supply path 28. In parallel, a voltage is supplied from the power source 13 to the electrode 11 and an electric field is applied in the processing space 14 to generate an atmospheric pressure glow discharge. Thereby, the film-forming gas is turned into plasma. The plasma gas comes into contact with the substrate 9 to cause a reaction. As a result, a crystal of the conductive metal oxide can be vapor-phase grown on the surface of the substrate 1. This conductive metal oxide is based on zinc oxide and contains gallium. The gallium content of the formed conductive metal oxide film is, for example, Ga / Zn = 1-5 wt% in terms of the zinc element ratio.
By employing a chemical film formation method using an organometallic compound as a raw material, the film formation cost can be reduced compared to a physical film formation method such as sputtering or vacuum deposition.

  The film-forming gas that has been processed is discharged from the processing space 14 to the exhaust passage 29, and is discharged to the atmosphere through a detoxification process.

[Oxidative post-treatment process]
As shown in FIG. 2, after the conductive metal oxide film is formed, an oxidizing post-treatment process is performed. The processing apparatus 1 is also used in the oxidative post-processing step subsequent to the film-forming step. The workpiece 90 is placed on the electrode / substrate support 12 as it is without being taken out of the processing space 14 and thus outside the chamber 19. Therefore, the conductive metal oxide film 92 is not exposed to the atmosphere after the film formation process until the oxidizing post-treatment process. Thereby, it can prevent that the water | moisture content etc. in air | atmosphere touch an electroconductive metal oxide, and raise | generate an unsuitable reaction. Even if it is exposed to the atmosphere, since the heat during film formation remains in the object 90 after the film formation and before the oxidizing post-treatment, the influence of moisture in the air is small. Further, the heating means 15 can keep the object 90 to be heated even after the film forming process is completed, so that the influence of moisture in the atmosphere can be substantially avoided.

  In the oxidizing post-treatment step, the heating temperature of the object 90 to be treated by the heating means 15 is preferably adjusted to about 100 ° C. to 300 ° C., more preferably about 200 ° C. to 300 ° C. This temperature range is sufficiently lower than the temperature that induces disturbance of the film structure (about 700 ° C.).

  In the oxidizing post-treatment process, the organometallic compound sources 21 and 22 are disconnected from the gas supply path 28. About the inert gas source 23 and the oxygen gas source 24, the state connected to the gas supply path 28 as it is is maintained.

Oxygen (O ₂ ) from the oxygen gas source 24 is diluted with nitrogen (N ₂ ) from the inert gas source 23 to obtain an oxidizing gas (O ₂ + N ₂ ) for oxidizing post-treatment. The oxygen concentration O ₂ / (O ₂ + N ₂ ) in the oxidizing gas can be set, for example, in the range of 5% by volume to 100%, preferably 50% by volume or more, more preferably 70% by volume or more, More preferably, it is about 100%. When the oxidizing gas is 100% oxygen, the amount of nitrogen supplied from the inert gas source 23 is zero.

An oxidizing gas (O ₂ + N ₂ or O ₂ 100%) is introduced into the processing space 14 via the gas supply path 28, and the gas in the entire processing space 14 is replaced with the oxidizing gas. The gas in the entire chamber 19 may be replaced with an oxidizing gas. In parallel, a voltage is supplied from the power source 13 to the electrode 11, and a voltage is applied between the electrodes 11 and 12 to generate an atmospheric pressure discharge. As a result, the oxidizing gas is turned into plasma (activated), and oxygen-based active species such as oxygen plasma, oxygen radicals, and ozone are generated. As a result, the oxidizing action of the oxidizing gas is expressed or promoted.

  In order to develop or promote the oxidation action, the heating means 15 may be stopped while the oxidizing gas is turned into plasma (activated). On the contrary, the oxidizing action can be expressed or promoted only by heating the object 90 by the heating means 15 without converting the oxidizing gas into plasma (activation). In this case, voltage supply from the power supply 13 is not performed.

  The oxidized oxidizing gas is brought into contact with the heated conductive metal oxide film 92 of the workpiece 90. Thereby, an oxidation reaction (oxidation action) occurs at the surface of the conductive metal oxide or at the crystal interface. By this oxidation reaction, organic impurities derived from the raw materials present on the surface of the conductive metal oxide film and the crystal interface can be removed. The heating temperature can be made lower than when organic impurities are removed in a non-oxygen atmosphere, and the film structure can be prevented from being disturbed. Further, the concentration of hydroxyl groups in the conductive metal oxide film can be reduced by oxidizing the metal-hydroxyl conjugate contained in the conductive metal oxide film. Thereby, the capture site | part of the carrier electron of an electroconductive metal oxide can be reduced. As a result, the mobility of carrier electrons can be increased.

  The treated oxidizing gas is discharged from the treatment space 14 to the exhaust passage 29, and is discharged to the atmosphere through a detoxification process.

[Reducing post-treatment process]
As shown in FIG. 3, a reducing post-treatment step is performed after the oxidizing post-treatment step. The processing apparatus 1 is also used in the reducing post-processing step following the film forming step and the oxidizing post-processing step. The workpiece 90 is placed on the electrode / substrate support 12 as it is without being taken out of the processing space 14 and thus outside the chamber 19. Therefore, the conductive metal oxide film 92 is not exposed to the atmosphere after the oxidizing post-treatment process and before the reducing post-treatment process. Thereby, it can prevent that the water | moisture content etc. in air | atmosphere touch an electroconductive metal oxide, and raise | generate an unsuitable reaction. Even if it is exposed to the atmosphere, since the heat during the oxidizing post-treatment remains in the object 90 after the oxidizing post-treatment process and before the reducing post-treatment, the influence of moisture in the atmosphere is not affected. small. Furthermore, by continuing to heat the object 90 after the end of the oxidative post-processing step by the heating means 15, the influence of moisture in the atmosphere can be substantially avoided.

  In the reducing post-treatment step, the heating temperature of the object 90 to be treated by the heating means 15 is preferably adjusted to about 200 ° C to 500 ° C.

  In the reducing process, the oxygen gas source 24 is disconnected from the gas supply path 28 while the inert gas source 23 is connected to the gas supply path 28, and instead, the hydrogen gas source 25 is connected to the gas supply path 28.

Hydrogen (H ₂ ) from the hydrogen gas source 25 is diluted with nitrogen (N ₂ ) from the inert gas source 23 to obtain a reducing gas (H ₂ + N ₂ ) for reducing post-treatment. The hydrogen concentration in the reducing gas can be set in a range of H ₂ / (H ₂ + N ₂ ) = 0.5% by volume or more. When oxygen can be completely excluded from the processing space 14, the reducing gas may be 100% hydrogen, and in that case, the amount of nitrogen supplied from the inert gas source 23 is zero. The hydrogen in the reducing gas is preferably about 0.5% to 10% by volume, more preferably about 1% to 5% by volume.

A reducing gas (H ₂ + N ₂ or H ₂ 100%) is introduced into the processing space 14 via the gas supply path 28, and the gas in the entire processing space 14 is replaced with the reducing gas. The gas in the entire chamber 19 may be replaced with a reducing gas. In parallel, a voltage is supplied from the power source 13 to the electrode 11, and a voltage is applied between the electrodes 11 and 12 to generate an atmospheric pressure discharge. As a result, the reducing gas is turned into plasma (activated), and hydrogen-based active species such as hydrogen plasma and hydrogen radicals are generated. As a result, the reducing action of the reducing gas is expressed or promoted.

  In order to develop or promote the reducing action, the reducing gas may not be converted into plasma (activated) and the object to be processed 90 may be heated only by the heating means 15. In this case, voltage supply from the power supply 13 is not performed. On the contrary, the heating means 15 may be stopped while the reducing gas is turned into plasma (activated).

The reducing gas comes into contact with the heated conductive metal oxide film 92 of the workpiece 90. Thereby, a reduction reaction (reduction action) occurs at the surface of the conductive metal oxide or at the crystal interface. By this reduction reaction, the surface of the conductive metal oxide film 92 can be stabilized, and oxygen and moisture in the air can be prevented from entering the surface of the conductive metal oxide film 92 and the crystal grain boundary, thereby generating carrier electrons. Can prevent the capture site of. In addition, oxygen vacancies can be increased and sufficient carrier electrons can be secured.
As a result, the electrical resistivity of the conductive metal oxide thin film can be reduced. Furthermore, an increase in electrical resistivity of the conductive metal oxide film with time can be reduced.

  The treated reducing gas is discharged from the processing space 14 to the exhaust passage 29, and is discharged to the atmosphere through a detoxification process.

  After completion of the reducing post-treatment process, the object 90 is removed from the chamber 19. Since the surface of the conductive metal oxide film 92 is stabilized, it is possible to prevent the conductive metal oxide film 92 from being deteriorated even when exposed to the air thereafter.

The present invention is not limited to the above embodiment, and various modes can be adopted within the scope of the gist.
For example, in the plasma forming means 10 of the film forming and post-processing apparatus 1, the processing space 14 in which the object to be processed 90 is disposed and the plasma space between the electrodes 11 and 12 are the same, and the object to be processed 90 is placed in the plasma space. This is a so-called direct method in which the plasma is in direct contact with the workpiece 90, but the processing space and the plasma space are separated, the processing space is connected to the plasma space, and plasma gas is ejected from the plasma space. In other words, so-called remote-type plasmarizing means for contacting the target object 90 in the processing space may be used. In this case, the substrate support means is provided separately from the electrode 12.
The plasmatizing means 10 generates a plasma discharge near atmospheric pressure, but may generate a plasma discharge under vacuum.
The oxidizing gas or reducing gas activating means may be a microwave irradiating means for activating the gas by irradiating microwaves instead of the plasma generating means, and activating the gas by irradiating with ultraviolet rays. It may be an ultraviolet irradiation means.
The oxidizing component of the oxidizing gas is not limited to oxygen (O ₂ ) or ozone (O ₃ ), and may be any that exhibits an oxidizing action, or any gas containing oxygen atoms, such as nitrous oxide. (N ₂ O) or the like may be used.
The reducing component of the reducing gas is not limited to hydrogen (H ₂ ), but may be anything that exhibits a reducing action, such as carbon monoxide (CO), hydrogen sulfide (H ₂ S), sulfur oxide (SOx), Formaldehyde or the like may be used.
As the inert gas source 23, a rare gas such as argon or helium may be used instead of nitrogen.

The apparatus for performing the film forming process and the apparatus for performing the post-processing process may be separated from each other.
The apparatus that performs the oxidizing post-treatment process and the apparatus that performs the reducing post-treatment process may be separate from each other.
As a method for forming the conductive metal oxide film, vacuum plasma CVD may be applied instead of atmospheric pressure plasma CVD, or thermal CVD may be applied. The conductive metal oxide film may be formed by a spray method or a sol-gel method without being limited to the CVD method. In the spray method, a raw material liquid containing an organometallic compound is sprayed on a substrate and crystallized by heating. In the sol-gel method, a raw material liquid containing an organometallic compound is applied to a substrate, and a sol-gel reaction is caused to crystallize.
The metal contained in the conductive metal oxide film is not limited to zinc and gallium, and may be indium, tin, titanium, cadmium, aluminum, antimony, or the like. The conductive metal oxide film is not limited to the zinc oxide type, and may be ITO, tin oxide, titanium oxide, cadmium oxide, aluminum oxide, antimony oxide, or the like. An organic metal compound raw material is appropriately selected according to the components of the film to be formed.
The object to be treated of the present invention may be a metal oxide film containing carbon, and is not limited to a film formed using an organometallic compound as a raw material.

Examples of the present invention will be described, but the present invention is not limited thereto.
[Film formation process]
Film formation was performed using the film formation and post-treatment apparatus 1 shown in FIG. As the substrate 91, non-alkali glass (# 1737) manufactured by Corning was used. The flow rate ratio of nitrogen (N ₂ ) and oxygen (O ₂ ) as the carrier gas was N ₂ : O ₂ = 1: 5.5. The carrier gas was vaporized and mixed with zinc acetylacetonate [Zn (acac) ₂ ] as a zinc raw material and gallium acetylacetonate [Ga (acac) ₂ ] as a gallium raw material to obtain a film forming gas. This film forming gas was introduced into the atmospheric pressure plasma space 14 to be converted into plasma and brought into contact with the substrate 91. The substrate temperature was 300 ° C. Thereby, the thin film was vapor-phase grown on the surface of the substrate 91.

The crystallinity, composition, and electrical resistivity of the obtained thin film were measured. Crystallinity was measured by X-ray diffraction method. As a result, as shown in FIG. 4, it was confirmed that the obtained thin film was a crystalline zinc oxide film. FIG. 4 is an enlarged view of a peak derived from the (002) plane of zinc oxide. When the composition of the film was measured by X-ray photoelectron spectroscopy, the film contained an amount of gallium estimated to be Ga / Zn = 1 to 5 wt% in terms of the zinc element ratio. Furthermore, the film contained about 3% carbon. The electrical resistivity was measured by the four-end needle method (the same applies to the following examples and comparative examples).
This film formation process end stage is referred to as Comparative Example 1. That is, the sample of Comparative Example 1 is not subjected to an oxidizing post-treatment and a reducing post-treatment after film formation. In Table 1, the electrical resistivity of Comparative Example 1 was set to 100.

[Oxidative post-treatment process]
Next, an oxidative post-treatment was performed on the above film. Oxidative post-treatment was performed by atmospheric pressure plasma treatment. As the oxidizing gas, 100% oxygen (O ₂ ) gas was used. This oxidizing gas was introduced into the processing space 14 between the electrodes 11 and 12 to be turned into plasma and brought into contact with the film. The substrate temperature was 300 ° C. The applied voltage between the electrodes 11 and 12 was Vpp = 6 kV. The frequency of the applied voltage was 180 kHz. The gap between the electrodes 11 and 12 was 1.0 mm.

  The component composition of the film after the oxidative post-treatment was measured by X-ray photoelectron spectroscopy and compared with that after the oxidative post-treatment and before the oxidative post-treatment. The result is shown in FIG. FIG. 5 is an enlarged view of the peak derived from the 1s orbital of oxygen. FIG. 4A shows the state after the film formation and before the oxidation post-treatment, and FIG. 4B shows the state after the oxidation post-treatment. The hatched portion in the figure is a peak indicating a hydroxyl group in the conductive metal oxide film. It was confirmed that the hydroxyl group concentration in the film was reduced by performing the oxidizing post-treatment. The carbon content in the film after the film formation and before the oxidative post-treatment process was 3%, whereas the carbon content in the film after the oxidative post-treatment process was 1%.

[Reducing post-treatment process]
Next, the film was subjected to a reducing post-treatment. The reducing post-treatment was performed by heat treatment. The substrate temperature was adjusted to 500 ° C. by the heating means 15. A reducing gas was brought into contact with this substrate. As the reducing gas, a mixed gas of 95 vol% nitrogen and 5 vol% hydrogen was used. The power source 13 was stopped and the reducing gas was not converted into plasma.

  After the reducing post-treatment, the electrical resistivity of the film was measured. The results are as shown in Table 1, and the electrical resistivity could be greatly reduced to 2% of Comparative Example 1 (after film formation and before oxidative post-treatment).

In Example 2, after performing the film forming process under the same contents and the same conditions as in Example 1, heat treatment was performed as an oxidizing post-treatment. The substrate temperature was adjusted to 300 ° C. by the heating means 15. An oxidizing gas was brought into contact with this substrate. As the oxidizing gas, 100% oxygen (O ₂ ) gas was used. The treatment time was 5 minutes. The power source 13 was stopped and the oxidizing gas was not converted into plasma.
Subsequently, a post-reduction treatment step having the same contents and the same conditions as in Example 1 was performed. That is, the film was heat-treated by using a mixed gas of 95 vol% nitrogen and 5 vol% hydrogen as the reducing gas and setting the substrate temperature to 500 ° C.
Then, when the electrical resistivity of the film was measured, as shown in Table 1, it was confirmed that the electrical resistivity could be reduced to 23% of Comparative Example 1 (after film formation and before oxidative post-treatment).
From the results of Examples 1 and 2, it was found that the oxidative post-treatment using atmospheric pressure plasma can increase the film conductivity than the oxidative post-treatment using only heat treatment.

In Example 3, the film forming process was performed under the same contents and the same conditions as in Example 1. Furthermore, the oxidizing post-treatment process was performed under the same conditions and conditions as in Example 1. That is, 100% oxygen (O ₂ ) gas was used as the oxidizing gas, and the conductive metal oxide film was subjected to atmospheric pressure plasma treatment. The substrate temperature was 300 ° C. Thereafter, a reducing post-treatment step was performed. In the reducing post-treatment step of Example 3, the reducing gas composition was 0.5 vol% hydrogen and 99.5 vol% nitrogen, and the other conditions were the same as those of the reducing post-treatment step of Example 1. That is, using a reducing gas having the above composition, the film was heat-treated at a substrate temperature of 500 ° C.
Then, when the electrical resistivity of the film was measured, as shown in Table 1, it was confirmed that the electrical resistivity could be reduced to 6% of Comparative Example 1 (after film formation and before oxidative post-treatment).
From Examples 1 to 3, when the oxidizing post-treatment is performed by atmospheric pressure plasma, the conductivity of the film is higher than when the oxidizing post-treatment is performed only by heat treatment even if the hydrogen concentration of the reducing post-treatment is low. It turns out that you can.

[Comparative Example 2]
In Comparative Example 2, only an oxidative post-treatment step by atmospheric pressure plasma treatment was performed as a post-treatment after film formation. That is, the film forming process is performed under the same contents and the same conditions as in Example 1, and then the oxidizing post-treatment process (at 100% oxygen and 300 ° C. atmospheric pressure plasma treatment) having the same contents and the same conditions as in Example 1. And reductive post-treatment was omitted. As a result, as shown in Table 1, the electrical resistivity of the film increased to 207% of Comparative Example 1 (after film formation and before oxidative post-treatment).

[Comparative Example 3]
In Comparative Example 3, only an oxidative post-treatment step by heat treatment was performed as a post-treatment after film formation. That is, the film forming step is performed under the same contents and the same conditions as in Example 2, and then the oxidative post-processing step (heat treatment at 100% oxygen and the substrate temperature of 300 ° C.) of the same contents and the same conditions as in Example 2 is performed. And the reducing post-treatment was omitted. As a result, as shown in Table 1, the electrical resistivity of the film was 104% of Comparative Example 1 (after film formation and before oxidative post-treatment).
From Examples 1 and 2 and Comparative Examples 2 and 3, the effect of improving the conductivity of the film is insufficient or adversely affected only by the oxidizing post-treatment, and the conductivity is obtained by combining the oxidizing post-treatment and the reducing post-treatment. It was confirmed that the effect of improving sex could be achieved.

[Comparative Example 4]
In Comparative Example 4, only a reducing post-treatment process by heat treatment was performed as a post-treatment after film formation. That is, the film forming process is performed under the same contents and the same conditions as in Example 1, and then the reducing post-treatment process with the same contents and the same conditions as in Example 1 (substrate temperature in a mixed gas atmosphere of 5 vol% hydrogen and 95 vol% nitrogen). (Heat treatment at 500 ° C.). An oxidative post-treatment step was not performed. As a result, as shown in Table 1, the electrical resistivity of the film was 61% of Comparative Example 1 (after film formation and before oxidative post-treatment).

[Comparative Example 5]
In Comparative Example 5, only the reducing post-treatment step by atmospheric pressure plasma treatment was performed as post-treatment after film formation. That is, the film forming process was performed under the same contents and the same conditions as in Example 1, and then the reducing gas was turned into plasma and brought into contact with the substrate. As a reducing gas, a mixed gas of 95 vol% nitrogen and 5 vol% hydrogen was used. The applied voltage and frequency between the electrodes 11 and 12 and the gap between the electrodes 11 and 12 were the same as in the oxidizing post-treatment of Example 1. The substrate temperature was 300 ° C. No oxidative post-treatment was performed. As a result, as shown in Table 1, the electrical resistivity of the film was 84% of Comparative Example 1 (after film formation and before oxidative post-treatment).
Comparative Examples 4 and 5 are conventionally known post-processing methods, but the effect of lowering the electrical resistivity was small compared to Examples 1 and 2 according to the present invention.

[Comparative Example 6]
In Comparative Example 6, the order of post-processing after film formation was changed with respect to Example 1. That is, after performing the film forming process under the same contents and the same conditions as those in Example 1, a reducing post-treatment process having the same contents and the same conditions as in Example 1 (substrate temperature in a mixed gas atmosphere of 5 vol% hydrogen and 95 vol% nitrogen) (Heat treatment at 500 ° C.). Thereafter, an oxidative post-treatment step (atmospheric pressure plasma treatment with oxygen of 100% and substrate temperature of 300 ° C.) having the same contents and the same conditions as in Example 1 was performed. As a result, as shown in Table 1, the electrical resistivity of the film significantly increased to 444% of Comparative Example 1 (after film formation and before oxidative post-treatment).
Thereby, in order to improve the electroconductivity of a film | membrane, the order of post-processing was important, and it was confirmed that an oxidizing post-treatment should be performed first and then a reducing post-treatment should be performed.

[Comparative Example 7]
In Comparative Example 7, after performing the film forming process under the same contents and the same conditions as in Example 1, an oxidizing post-treatment process (at 100% oxygen and atmospheric pressure with a substrate temperature of 300 ° C.) having the same contents and the same conditions as in Example 1. Plasma treatment) was performed. Thereafter, the film was heat-treated in an atmosphere of 100% nitrogen. The substrate temperature for the heat treatment was 500 ° C. As a result, as shown in Table 1, the electrical resistivity of the film was 34% of Comparative Example 1 (after film formation and before oxidative post-treatment).
From Example 1 and Comparative Example 7, it was confirmed that in the heat treatment subsequent to the oxidative post-treatment, the conductivity of the film can be further increased if a reducing component such as hydrogen is included in the atmosphere.

[Comparative Example 8]
In Comparative Example 8, after performing the film forming process under the same contents and the same conditions as in Example 1, 100% nitrogen gas was converted into plasma, and the film was subjected to atmospheric pressure plasma treatment. The substrate temperature was 300 ° C. The conditions for atmospheric pressure plasma treatment were the same as in Example 1 except for the gas composition. No reducing post-treatment was performed. As a result, as shown in Table 1, the electrical resistivity of the film was 106% of Comparative Example 1 (after film formation and before oxidative post-treatment).

[Comparative Example 9]
In Comparative Example 9, after performing the film forming step under the same contents and the same conditions as in Example 1, the oxidizing gas consisting of 5% oxygen and the balance nitrogen was turned into plasma, and the film was subjected to atmospheric pressure plasma treatment. The substrate temperature was 300 ° C. The conditions for the oxidizing post-treatment were the same as in Example 1 except for the gas composition. No reducing post-treatment was performed. Thereafter, the electrical resistivity of the film was measured. As a result, as shown in Table 1, the electrical resistivity was 128% of Comparative Example 1 (after film formation and before oxidative post-treatment).

[Comparative Example 10]
In Comparative Example 10, the film forming process was performed under the same conditions and the same conditions as in Example 1, and then an oxidizing gas composed of 27% oxygen and the balance nitrogen was turned into plasma, and the film was subjected to atmospheric pressure plasma treatment. The substrate temperature was 300 ° C. The conditions for the oxidizing post-treatment were the same as in Example 1 except for the gas composition. No reducing post-treatment was performed. As a result, as shown in Table 1, the electrical resistivity of the film was 110% of Comparative Example 1 (after film formation and before oxidative post-treatment).

[Comparative Example 11]
In Comparative Example 11, the film forming process was performed under the same contents and the same conditions as in Example 1, and then an oxidizing gas composed of 73% oxygen and the balance nitrogen was converted into plasma, and the film was subjected to atmospheric pressure plasma treatment. The substrate temperature was 300 ° C. The conditions for the oxidizing post-treatment were the same as in Example 1 except for the gas composition. No reducing post-treatment was performed. As a result, as shown in Table 1, the electrical resistivity of the film was 64% of Comparative Example 1 (after film formation and before oxidative post-treatment).
From Comparative Examples 8 to 11, it was confirmed that the effect of improving the conductivity of the film was insufficient or adversely affected only by nitrogen plasma treatment or only by oxidizing post-treatment.

The results of the above examples and comparative examples are summarized in Table 1. In Table 1, the contents of the first post-processing after the film formation are described in the “post-processing 1” column, and the contents of the post-processing performed next are described in the “post-processing 2” column. It was confirmed that the conductivity of the conductive metal oxide can be significantly improved by performing the two-step post-treatment of the present invention.

Furthermore, the sample corresponding to Comparative Example 1, that is, the sample that was not subjected to any post-treatment and the sample of Example 1 were allowed to stand in an air atmosphere for 2 weeks, and then the electrical resistivity of these samples was measured. The results are shown in Table 2. In the sample corresponding to Comparative Example 1, the electrical resistivity increased to 278% of the initial value (immediately after film formation). In contrast, the electrical resistivity of the sample of Example 1 was 125% of the initial value (immediately after the oxidative post-treatment and immediately after the reductive post-treatment). It was confirmed that the post-treatment process according to the present invention can reduce the increase in electrical resistivity over time.

  The present invention can be applied, for example, to the field of manufacturing transparent electrodes for displays and solar cells.

DESCRIPTION OF SYMBOLS 1 Film-forming and post-processing apparatus 10 Processing part (Plasmaization means, activation means)
DESCRIPTION OF SYMBOLS 11 Upper electrode 12 Lower electrode and board | substrate support part 13 Power supply 14 Processing space, plasma space 15 Heating means 19 Chamber 20 Gas supply system 21 Vaporizer (zinc containing organometallic compound source)
22 Vaporizer (Gallium-containing organometallic compound source)
23 Inert gas source 24 Oxygen gas source (oxidizing component source)
25 Hydrogen gas source (reducing component source)
28 Gas supply passage 29 Exhaust passage

Claims (9)

A post-treatment method for forming a conductive metal oxide containing carbon and then performing the process on the conductive metal oxide film,
An oxidizing post-treatment step in which an oxidizing gas having an oxidizing action is brought into contact with the conductive metal oxide film;
A reducing post-treatment step of bringing a reducing gas having a reducing action into contact with the conductive metal oxide film after the oxidizing post-treatment step;
A post-treatment method for a conductive metal oxide film, comprising:   2. The oxidizing gas is activated by one activating means selected from the group of plasma forming means, microwave irradiating means, and ultraviolet irradiating means in the oxidizing post-treatment step. Post-processing method.   The post-treatment method according to claim 1, wherein the conductive metal oxide film is heated in the oxidizing post-treatment step.   The post-treatment method according to any one of claims 1 to 3, wherein the oxidizing gas contains 5% by volume to 100% of oxygen.   5. The reducing gas is activated by one activating means selected from the group of plasma forming means, microwave irradiating means, and ultraviolet irradiating means in the reducing post-treatment step. A post-processing method according to any one of the above.   The post-treatment method according to claim 1, wherein the conductive metal oxide film is heated in the reducing post-treatment step.   The post-treatment method according to claim 1, wherein the reducing gas contains 0.5% by volume or more of hydrogen.   The post-treatment method according to claim 1, wherein the conductive metal oxide is formed from a raw material containing an organometallic compound. An apparatus for forming a conductive metal oxide containing carbon and performing post-treatment after film formation,
(A) a support for supporting the substrate in the processing space;
(B) Plasmaizing means including an electrode that forms a plasma space that is the same as or continuous with the processing space;
(C) heating means for heating the substrate;
(D) A film forming gas containing the conductive metal oxide raw material, an oxidizing gas having an oxidizing action on the conductive metal oxide film, and a reducing action on the conductive metal oxide film A gas supply system that selects one of the reducing gases, supplies the plasma space, and supplies the processing space;
The film forming and post-processing apparatus is characterized in that the selection is performed in the order of the film forming gas, the oxidizing gas, and the reducing gas.