Photoresist ashing in nitrogen gas using ferrite core inductively coupled plasmas

The characteristics of photoresist (PR) ashing using N 2 plasmas in a ferrite core inductively coupled plasma etcher have been studied and the effect of bias power and gas flow rate on PR ash rate and low- k material etch rate has been investigated. Fourier transform infrared spectroscopy revealed that the ashing process with N 2 gas produced less damage to the low- k material compared to the process with O 2 gas. The HF etch test was used to evaluate the ash damage to the low- k material.