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.

主权项

1. A method for etching a substrate, comprising:
arranging a substrate including a first structure and a dummy structure in a processing chamber, wherein the first structure is made of a material selected from a group consisting of silicon dioxide and silicon nitride, and wherein the dummy structure is made of silicon; supplying carrier gas to the processing chamber; supplying nitrogen trifluoride (NF3) and molecular hydrogen (H2) gas to the processing chamber, wherein the H2 is supplied at a greater flow rate than the NF3; and striking plasma in the processing chamber in the presence of the supplied NF3 and H2 gas to perform an NF3/H2 plasma etch process to etch the dummy structure.