Titanium oxide photocatalyst thin film and production method of titanium oxide photocatalyst thin film

Abstract

The present invention provides a titanium oxide photocatalytic thin film having a surface layer containing silicon oxide and titanium oxide and a production method for producing a titanium oxide photocatalytic thin film having a surface layer containing silicon oxide and titanium oxide and comprising a step of radiating excimer beam to the titanium oxide thin film while heating substrate on which the titanium oxide thin film is disposed in vacuum or gas atmosphere in the presence of a silicon-including compound.

What is claimed is:  
     
         1 . A titanium oxide photocatalytic thin film comprising a surface layer including silicon oxide and titanium oxide.  
     
     
         2 . A titanium oxide photocatalytic thin film according to  claim 1 , wherein the titanium oxide photocatalytic thin film is disposed on a substrate.  
     
     
         3 . A titanium oxide photocatalytic thin film according to  claim 1 , wherein the titanium oxide photocatalytic thin film is disposed on a substrate and at least one of a reflection prevention film and a protection film is disposed between the titanium oxide photocatalytic thin film and the substrate.  
     
     
         4 . A titanium oxide photocatalytic thin film according to  claim 1 , wherein the film thickness of the titanium oxide photocatalytic thin film is in a range from 10 to 120 nm or 180 to 230 nm.  
     
     
         5 . A production method of a titanium oxide photocatalytic thin film comprising a surface layer including silicon oxide and titanium oxide, the production method comprising the steps of: 
 forming a titanium oxide thin film on a substrate; and    radiating excimer beam to the titanium oxide thin film while heating the substrate in a vacuum or a gas atmosphere in the presence of a compound, which includes silicon.    
     
     
         6 . A production method of a titanium oxide photocatalytic thin film according to  claim 5 , wherein the compound, which includes silicon, is a compound containing —Si—O— bond.  
     
     
         7 . A production method of a titanium oxide photocatalytic thin film according to  claim 5 , wherein the gas atmosphere is one of a reductive gas atmosphere and a nitrogen gas atmosphere.  
     
     
         8 . A production method of a titanium oxide photocatalytic thin film according to  claim 5 , wherein the heating temperature of the substrate is in a range from room temperature to 300° C.  
     
     
         9 . A production method of a titanium oxide photocatalytic thin film according to  claim 5 , wherein the heating temperature of the substrate is in a range from 50° C. to 230° C.  
     
     
         10 . A production method of a titanium oxide photocatalytic thin film according to  claim 5 , wherein the substrate comprises a plastic substrate and the substrate heating temperature is in a range from room temperature to the heat resistant temperature of the plastic substrate.  
     
     
         11 . A production method of a titanium oxide photocatalytic thin film according to  claim 5 , further comprising the step of disposing a reflection prevention film between the titanium oxide thin film and the substrate.  
     
     
         12 . A production method of a titanium oxide photocatalytic thin film according to  claim 11 , wherein the reflection prevention film comprises an inorganic oxide thin film.  
     
     
         13 . A production method of a titanium oxide photocatalytic thin film according to  claim 11 , wherein the refractive index of the reflection prevention film is within a range from 1.5 to 2.3.  
     
     
         14 . A production method of a titanium oxide photocatalytic thin film according to  claim 11 , 
 wherein the refractive index of the reflection prevention film is between the refractive index of the substrate and the refractive index of the titanium oxide photocatalytic thin film; and    the optical film thickness, as expressed by a product of the film thickness and the refractive index of the reflection prevention film, is one of ¼ of a wavelength and a whole number multiple of ¼ of the wavelength, wherein the wavelength is in the vicinity of the center of the visible light range.    
     
     
         15 . A production method of a titanium oxide photocatalytic thin film according to  claim 11 , wherein the optical film thickness of the reflection prevention film, as expressed by a product of the film thickness and the refractive index of the reflection prevention film, is in a range from 110 nm to 160 nm or 330 nm to 480 nm.  
     
     
         16 . A production method of a titanium oxide photocatalytic thin film according to  claim 5 , further comprising a step of disposing a protection film between the titanium oxide thin film and the substrate wherein the substrate comprises a plastic substrate.  
     
     
         17 . A production method of a titanium oxide photocatalytic thin film according to  claim 16 , wherein the protection film comprises an inorganic oxide thin film.  
     
     
         18 . A production method of a titanium oxide photocatalytic thin film according to  claim 17 , wherein the inorganic oxide thin film is selected from a group consisting of an amorphous titanium oxide thin film, SnO 2  thin film, a SiO 2  thin film, and an ITO thin film.  
     
     
         19 . A production method of a titanium oxide photocatalytic thin film according to  claim 16 , wherein the refractive index of the protection film is in a range from 1.4 to 2.3.  
     
     
         20 . A production method of a titanium oxide photocatalytic thin film according to  claim 16 , 
 wherein the refractive index of the protection film is between the refractive index of the substrate and the refractive index of the titanium oxide photocatalytic thin film; and    the optical film thickness, as expressed by a product of the film thickness and the refractive index of the protection film, is one of ¼ of a wavelength and a whole number multiple of ¼ of the wavelength, wherein the wavelength is in the vicinity of the center of the visible light range.