Method for forming an interconnect structure using a CVD organic BARC to mitigate via poisoning

摘要

A method for forming a metal interconnect structure in a semiconductor device with the elimination of via poisoning during trench mask formation employs a CVD organic BARC that isolates the low k dielectric film. The CVD organic BARC is deposited over the low k dielectric film and in the via hole. Once the trench mask has been formed on the CVD organic BARC, the CVD organic BARC may be removed in the same process as the photoresist of the trench mask layer. A properly formed trench will have been created since the via poisoning and resist scumming were substantially eliminated by the presence of the CVD organic BARC.