Patent ID: 7955581

Claim:
A method for producing a silicon oxide, wherein: a vapor deposition apparatus is utilized, the vapor deposition apparatus comprising a vacuum chamber, a gas supply inlet for supplying an oxygen-containing gas into the vacuum chamber, a pressure reduction outlet for reducing pressure inside the vacuum chamber and an electron beam heater, and the method comprises steps of: (a1) disposing a metal substrate and a target essentially consisting of silicon inside the vacuum chamber; (a2) creating an oxygen atmosphere by supplying the oxygen-containing gas from the gas supply inlet, while reducing pressure inside the vacuum chamber; (a3) heating the target with the electron beam heater for evaporating silicon atoms from the target; (a4) forming a silicon oxide layer on the substrate by reaction between the evaporated silicon atoms and oxygen in the oxygen atmosphere; and (b) obtaining silicon oxide particles by separating the silicon oxide layer from the substrate and then pulverizing the separated silicon oxide layer, wherein a molar ratio of oxygen atoms to silicon atoms in the silicon oxide particles is 0.2 to 0.9.