Residue free systems and methods for isotropically etching silicon in tight spaces

摘要

Systems and methods for etching a substrate include arranging a substrate including a first structure and a dummy structure in a processing chamber. The first structure is made of a material selected from a group consisting of silicon dioxide and silicon nitride. The dummy structure is made of silicon. Carrier gas is supplied to the processing chamber. Nitrogen trifluoride and molecular hydrogen gas are supplied to the processing chamber. Plasma is generated in the processing chamber. The dummy structure is etched.