Post-Etch Cleaning for Porous Low K Integration: Impact of HF wet etch on "Pore-sealing" and "k recovery"

We investigated the compatibility of "HF-Based" cleaning with porous low-k integration, and "pore-sealing" approach and specific attention was paid to ULK porosity evolution. We also tried to demonstrate if "k-recovery" could be achieved by thinning the modified surface layer in the pattern trench walls (plasma damaged layer).