LOW DIELECTRIC CONSTANT MATERIAL DEPOSITED BY HDP-CVD FOR BARRIER AND ETCH STOP APPLICATION IN CU DAMASCENE STRUCTURE

摘要

A low dielectric constant barrier/etch stop material deposited by high density plasma CVD has been developed for use in copper damascene processes. The film is an amorphous silicon carbide material (a-Si,C:H), deposited using silane and methane as precursors. The film has a dielectric constant of ～3.8, a compressive stress of 1.0～1.5X10~9 dynes/cm~2, and leakage current density of 5X10~(-10) A/cm~2 at IMV/cm. HDP-CVD a-Si,C:H does not etch in ACT or EKC solutions. The film has been successfully integrated with fluorine-doped silicate glass (FSG) deposited using HDP-CVD for single and dual damascene structures. When integrated in-situ with HDP-FSG, an effective constant of 3.5 can be achieved.