Method for making a silicon dioxide layer on a silicon substrate by anodic oxidation

Abstract

A method for forming silicon dioxide layer on a silicon substrate by anodic oxidation includes: providing a silicon substrate which has a polished face; providing an anodic oxidation apparatus which is filled with an electrolyte; providing a platinum piece and placing the platinum piece in the electrolyte as a cathode; placing the silicon substrate in the electrolyte as an anode with the polished surface of the silicon substrate facing to the cathode; applying a direct current to the cathode and the anode and irradiating the electrolyte with ultraviolet light for a predetermined period of time; taking out the silicon substrate and getting a finished silicon dioxide layer formed on the silicon substrate after cleaning, drying and cooling. The method can increase the reaction rate, and the silicon dioxide layer so formed has a uniform thickness and high purity.

Dependencies are inferred from the claim text.