| abstract |
A disclosed etching method involves (a) providing a substrate in a chamber of a plasma treatment system. The substrate includes a silicon-containing film. The method further involves (b) etching the silicon-containing film with a chemical species in plasma generated from a process gas in the chamber. The process gas includes a phosphorus gas component, a fluorine gas component, and a hydrogen gas component. The hydrogen gas component contains at least one component selected from the group consisting of hydrogen fluoride, H<sub>2</sub>, ammonia, and hydrocarbons. |