Studies on the Reaction of Development-free Vapor Photolithography (DFVP).

Abstract

Based on the reaction of vapor HF and SiO2 at a temperature of above 100°C, development-free vapor photolithography (DFVP) eliminates the development step in conventional process. Under the etching condition, only in the presence of accelerators can the etching reaction occur. The accelerators catalyze this nucleophilic reaction by raising the nucleophilic activity of HF or activating the leaving group in substrate. Photochemical reaction leads to the concentration difference of accelerators between exposed area and unexposed area and thus results in the area-selective etching.