Optimization of wet clean and its cost effectiveness in dual Damascene 14 nm BEOL

Abstract

The purpose of this paper is to study the effects of post etch residue cleaning process on Via first dual Damascene scheme for BEOL on 14 nm Technology. Wet clean process was optimized using different chemicals, their formulations and processing times to address the impact on POR critical dimensions, ULK stability, organic residue removal capability, via resistance performance, and electromigration lifetime. In order to visualize the equivalent cleaning process with reduced chemical cost for HVM implementation of wet cleans changes, the cost evaluations are focused. The study suggests that cost of the ownership for wet cleans process could be significantly reduced while maintaining the similar particle removal efficiency.