JPH0792447B2 - Manufacturing method of metal oxide film and manufacturing method of sensor array - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a metal oxide film and a method for producing a sensor array in which a metal oxide film is integrated in order to utilize the sensing function of the metal oxide film.

2. Description of the Related Art Conventionally, a method of manufacturing a metal oxide film is roughly classified into a method using a vacuum device and a method not using a vacuum device. As a method of using a vacuum apparatus, there are a sputtering method of forming a thin film by sputtering with a bulk sintered body as a target, a reactive vapor deposition method using an electron beam, and the like. As a method that does not use a vacuum device, plasma spraying method in which metal oxide is melted and vaporized by high temperature plasma to form a thin film on the substrate and then annealed, screen printing in which a paste containing a metal oxide is screen-printed and then annealed after the thin film is formed Method, a sol-gel method of hydrolyzing a metal alkoxide to produce a gelled product, and thermally anneal it to the substrate, then an organic acid salt solution that applies an organic acid salt solution to the substrate and anneals it after heat decomposition, a metal salt solution. A spray pyrolysis method in which a substrate is pyrolyzed and then annealed by spraying is used. Further, the metal oxide film produced by such a method has a characteristic that the electric conductivity changes due to adsorption of gas or moisture. This property has been applied to sensors.

Conventionally, this kind of sensor was used for numerical comparison of specific gases, but recently, by integrating multiple sensors with different gas detection sensitivities and performing arithmetic processing on the detection output of each sensor to form a pattern. , Qualitative comparison of gas components and feature extraction have been performed, and a sensor system having a recognition / learning function has been developed. For such a purpose, as a method of integrating a plurality of sensors, conventionally, a method of dispersing a metal oxide powder in an organic polymer and a solvent to form a paste, and printing the paste has been performed (Japanese Patent Laid-Open No. 2004-242242). Sho 60-29651).

Problems to be Solved by the Invention Metal oxide films obtained by a method using a vacuum device have a dense film quality, but costly because large-scale equipment is required for uniform film formation in a large area. Has become one of. The metal oxide film obtained by a method that does not use a vacuum device has a low cost, but has a defect that the film quality is not dense.

Further, in a sensor that uses the characteristic that the electric conductivity changes due to the adsorption of gas or moisture of the metal oxide film, the difference in the manufacturing method affects the sensor characteristic. That is, the method that does not use a vacuum device, which is a low-cost manufacturing method, has a drawback that the response speed is slow because the film quality is not dense. Further, when a sensor is integrated, when a metal oxide film formed by using a vacuum method is etched by a photolithographic method using a resist, the resistance of the resist to an etching solution limits the metal oxide.

The present invention has been made to improve such drawbacks, and is intended to obtain a dense film at a low temperature at a low temperature. When a sensor is integrated, the integration can be easily performed. Is.

Means for Solving the Problems The present invention applies a metal oxide film by applying at least one kind of an organometallic compound to a substrate and performing heat treatment in an oxidizing atmosphere consisting of a gas containing at least one of oxygen and ozone and ultraviolet rays. It is manufactured. Patterning ability can be provided by making the organometallic compound photosensitive. Further, as the organometallic compound having photosensitivity, a compound having a film-forming property of undergoing a crosslinking reaction by light is particularly preferable.

The method for producing the sensor array of the present invention comprises a step of applying at least one kind of film-forming organometallic compound that undergoes a crosslinking reaction by light to a substrate, a step of patterning the organometallic compound on the substrate with ultraviolet rays, and a developing solution. And a heat treatment in an oxidizing atmosphere composed of a gas containing at least one of oxygen and ozone and ultraviolet rays to obtain a metal oxide film.

The wavelength of ultraviolet rays used in the step of forming the pattern is preferably 350 nm or less.

Further, the method for manufacturing the sensor array of the present invention comprises the steps of applying an organometallic compound to a substrate, applying a resist on the organometallic compound, forming a pattern on the resist, and using the resist pattern as a mask. It includes a step of etching the organometallic compound and a step of obtaining a metal oxide film by heat treatment in an oxidizing atmosphere composed of a gas containing at least one of oxygen and ozone and ultraviolet rays.

Further, the method for manufacturing the sensor array of the present invention comprises a step of applying at least one kind of an organometallic compound to a substrate, and a step of applying the organometallic compound on the substrate in an oxidizing atmosphere composed of a gas containing at least one of oxygen and ozone and ultraviolet rays. Heat treatment to obtain a metal oxide film, a step of applying a resist on the metal oxide film, a step of forming a pattern on the resist, and a step of etching the metal oxide film using the resist pattern as a mask Is included.

Action In the present invention, since the atmosphere at the time of heat-treating the organometallic compound to obtain the metal oxide film is an oxidizing atmosphere consisting of a gas containing at least one of oxygen and ozone and ultraviolet rays, the ozone generation efficiency is As a result, the oxidation reaction is facilitated and the oxidation reaction can be carried out at a relatively low temperature.

The metal oxide film of the present invention obtained by the above-mentioned structure has a low cost and a dense film quality, and when the sensor is formed, the response speed becomes fast. When manufacturing a sensor array in which sensors are integrated, the number of steps is reduced, and since the oxidation reaction is performed at a low temperature, there is no restriction on the type of substrate.

Examples Examples of the present invention will be described below. Examples of the metal-containing organic compound used in the present invention include a halogen compound, a carbonyl compound, a compound having a hydroxyl group, and a chelate compound. Preferably, these compounds have film-forming properties.

Further, a polymer containing the above compound can also be used. The metal contained in the polymer may be contained in either the main chain or the side chain of the polymer, and may be a mixture of the polymer containing metal and the polymer containing no metal, or containing metal. It may be a mixture of a non-polymer and an organic compound containing a metal.

Further, the kind of metal is not limited to the examples, and any metal that can bond with an organic compound can be used.

Next, the present invention will be described with reference to the drawings.

Example 1 A 20% solution is prepared by using tin caprylate as an organic compound containing metal and butanol as a solvent. Next, as shown in FIG. 1, the above-mentioned prepared solution is applied onto the substrate 1 by spin coating. This substrate is dried in the atmosphere for 30 minutes and then at 120 ° C. for 30 minutes (FIG. 1b). Next, the above-mentioned substrate is put into a reaction vessel provided with the low-pressure mercury lamp 5 and the ozonizer 4 to cause an oxidation reaction. At this time, the substrate is heated to 200 degrees. Tin oxide 6 is obtained on the substrate 1. When the specific resistance at room temperature of the obtained tin oxide film was measured, it was 10 ⁷ ohms when the oxidation treatment time was 0 minutes, and decreased to 10 ³ ohms when the oxidation treatment time was 30 minutes.

(Example 2) Next, a method for producing a metal oxide pattern using the tin caprylate solution prepared in the same manner as in Example 1 will be described.
As in Example 1, the above-mentioned preparation liquid was applied to the substrate 1 and dried to obtain a substrate to which tin caprylate was attached (Fig. 2b).
Next, ultraviolet light (300 nm or less) 8 is irradiated through the mask 7 to crosslink the tin caprylate. Next, butanol is used as a phenomenon liquid to remove uncrosslinked tin caprylate (Fig. 2c). This substrate is oxidized similarly to the first embodiment. The specific resistance of the tin oxide obtained here was 10 ⁴ ohms.

(Example 3) Next, a method for manufacturing a sensor array by integrating metal oxides will be described with reference to process cross-sectional views FIGS. 3 and 4. The tin caprylate preparation liquid is applied to the substrate 1 on which the electrodes 9 are formed as shown in FIG. 3 in the same manner as in Example 1, and a substrate to which tin caprylate is attached is obtained after drying. Next, ultraviolet light (300 nm or less) 8 is irradiated through the mask 7 to crosslink the tin caprylate, and after the phenomenon, a substrate to which tin caprylate is attached is obtained. After that, oxidation treatment is performed to obtain a sensor array in which tin oxide films are integrated and arranged. The variation in the specific resistance of the sensor at this time was 5% in standard deviation.

FIG. 4 is a sectional view showing a process of integrating a sensor array by using ultraviolet light for patterning having a wavelength of 300 nm or more. The resist (CIR702 made by JSR) 10 is applied to the one to which tin caprylate is attached after the above-mentioned treatment. After that, after irradiating the ultraviolet light 11 through the mask 7, the resist phenomenon occurs (FIG. 4c). Then, using this as a mask, the tin caprylate is etched with butanol (Fig. 4d). Oxidation is performed with the resist left (4th
Figure e). In this way, a sensor array in which tin oxide films are integratedly arranged is obtained.

It is also possible to integrate and arrange a plurality of metal oxides using such an integration method.

INDUSTRIAL APPLICABILITY The present invention is not limited to a single metal oxide, but is effective even in a mixed or composite metal oxide as long as an organic compound containing an initial metal is mixed or a composite is used. For example, addition of impurities. Furthermore, it is obvious that such metal oxides are widely effective not only for sensors but also for electronic materials (wiring materials, electrode materials, superconducting materials, etc.) and electronic device manufacturing utilizing the characteristics of metal oxides. .

EFFECTS OF THE INVENTION As described above, according to the present invention, it is possible to obtain a dense metal oxide film at low temperature at low cost from a metal-containing organic compound, and it is possible to manufacture not only sensors but also electronic materials and electronic devices. It provides a new method and is extremely useful in industry. Further, when the sensor is integrated, the sensor array is not limited to the resist, and the sensor array can be easily manufactured, and at the same time, it provides an effective means in the integration method of other electronic materials and electronic devices. It is a thing.

[Brief description of drawings]

FIG. 1 is a process sectional view of a method of manufacturing an oxide film according to an embodiment of the present invention, and FIGS. 2, 3, and 4 are sectional views of manufacturing process of a sensor array. 1 ... Substrate, 2 ... Tin caprylate (organic compound containing metal) and butanol, 3 ... Tin caprylate, 5 ...
… Low-pressure mercury lamp, 6 …… tin oxide, 8 …… UV light.

Claims (6)

[Claims] 1. A metal oxide film is obtained by applying at least one kind of an organometallic compound to a substrate and heat-treating it in an oxidizing atmosphere consisting of a gas containing at least one kind of oxygen and ozone and ultraviolet rays. Manufacturing method of metal oxide film. 2. The method for producing a metal oxide film according to claim 1, wherein the organometallic compound has photosensitivity. 3. A step of applying at least one kind of an organometallic compound having a film-forming property which undergoes a crosslinking reaction by light to a substrate, a step of patterning the organometallic compound on the substrate with ultraviolet rays, and a step of developing with a developer. And a step of obtaining a metal oxide film by heat treatment in an oxidizing atmosphere composed of a gas containing at least one of oxygen and ozone and ultraviolet rays. 4. The method for producing a sensor array according to claim 3, wherein the wavelength of ultraviolet rays used in the step of forming the pattern is 350 nm or less. 5. A step of applying an organometallic compound to a substrate, a step of applying a resist on the organometallic compound, a step of forming a pattern on the resist, and a step of etching the organometallic compound using the resist pattern as a mask. And a step of obtaining a metal oxide film by performing a heat treatment in an oxidizing atmosphere composed of a gas containing at least one of oxygen and ozone and ultraviolet rays. 6. A step of applying at least one kind of an organometallic compound to a substrate, a heat treatment of the organometallic compound on the substrate in an oxidizing atmosphere consisting of a gas containing at least one of oxygen and ozone and ultraviolet rays to obtain a metal oxide. A step of obtaining a film, a step of applying a resist on the metal oxide film, a step of forming a pattern on the resist, and a step of etching the metal oxide film using the resist pattern as a mask. Manufacturing method of sensor array.