Properties of Interlayer Low Dielectric Polyimide during Aluminium Etching with Electron Cyclotron Resonance Etcher System

Abstract

The properties of polyimide for interlayer dielectrics application are investigated during plasma etching of Al on it. Cl-based plasma generally used for Al etching results ing an increase in the dielectrics constant of polyimide, while SF6 plasma exhibits a high polyimide etch rate and a reducing effect of the dieletric constant. The leakage current of polyimide is significantly suppressed after plasma wxposure. An optimal combination of al etch with Cl2 plasma and polyimide etch with SF6 plasma is expected to be a good tool for realizing multilevel metallization structures.