Challenges of Post Cu CMP Cleaning (II)

摘要

As people gain more experience and knowledge about Cu CMP and post Cu CMP cleaning processes, more issues are uncovered and beg for solutions. Beyond removing slurry abrasive particles and metallic contamination from all surfaces, Cu cleaning processes are required to be gentle to the Cu surface and liner material, as well as corrosion-free. In terms of production-worthiness, Cu cleaning process is also required to be robust across different CMP platforms and consumables, and perform consistently over a large number of wafers. Because of the evolving nature of the Cu CMP process, these requirements present significant challenges to post CMP cleaning. In this paper, long term performance of Lam's proprietary Cu cleaning process and concerns such as corrosions, Cu/Low K integration and electrical performance will be discussed.