Method for producing glass with fine structure

Abstract

The present invention provides a method for producing a glass with a fine structure, the method being capable of avoiding forming a hole with a shallow wall angle and capable of producing a glass with a fine structure such as a deep hole or groove extending with high straightness in the thickness direction of a substrate. The present invention relates to a method for producing a glass with a fine structure, the method including an etching step of etching a glass by irradiating the glass with an ultrasonic wave, wherein: an etchant used in the etching step includes hydrofluoric acid, at least one inorganic acid selected from the group consisting of nitric acid, hydrochloric acid, and sulfuric acid, and a surfactant; and in the etchant, a concentration of the hydrofluoric acid is 0.05 mass % to 8.0 mass %, a concentration of the inorganic acid is 2.0 mass % to 16.0 mass %, and a content of the surfactant is 5 ppm to 1000 ppm.

1 . A method for producing a glass with a fine structure, the method comprising an etching step of etching a glass by irradiating the glass with an ultrasonic wave, wherein
 an etchant used in the etching step comprises:   hydrofluoric acid;   at least one inorganic acid selected from the group consisting of nitric acid, hydrochloric acid, and sulfuric acid; and   a surfactant, and   in the etchant, a concentration of the hydrofluoric acid is 0.05 mass % to 8.0 mass %, a concentration of the inorganic acid is 2.0 mass % to 16.0 mass %, and a content of the surfactant is 5 ppm to 1000 ppm.   
     
     
         2 . The method for producing a glass with a fine structure according to  claim 1 , further comprising, prior to the etching step, a step of forming a modified portion or a processing hole by irradiating the glass with a laser pulse. 
     
     
         3 . The method for producing a glass with a fine structure according to  claim 1 , wherein an oscillation frequency in the irradiation with the ultrasonic wave is 100 kHz or less. 
     
     
         4 . The method for producing a glass with a fine structure according to  claim 1 , wherein an intensity of the ultrasonic wave is 0.10 W/cm 2  to 5.0 W/cm 2 . 
     
     
         5 . The method for producing a glass with a fine structure according to  claim 1 , wherein the inorganic acid is nitric acid. 
     
     
         6 . The method for producing a glass with a fine structure according to  claim 1 , wherein the content of the surfactant is 10 ppm to 800 ppm. 
     
     
         7 . The method for producing a glass with a fine structure according to  claim 1 , wherein the surfactant is a non-ionic surfactant. 
     
     
         8 . The method for producing a glass with a fine structure according to  claim 1 , wherein the glass is a low-alkali glass or alkali-free glass containing TiO 2  in an amount of 0.1 mol % or more and less than 5.0 mol %. 
     
     
         9 . The method for producing a glass with a fine structure according to  claim 1 , wherein the glass is a low-alkali glass or alkali-free glass containing CuO in an amount of 0.1 mol % or more and 2.0 mol % or less. 
     
     
         10 . The method for producing a glass with a fine structure according to  claim 1 , wherein the fine structure in the glass subjected to the etching step is a through hole, and a wall angle of the through hole is 80° or more.