Cleaning, rinsing and drying issues in post-Cu CMP cleaning: A case study
Fyen, Wim Vos, R Vrancken, E Grillaert, J Meuris, M Heyns, M #
Vsp bv-c/o brill acad publ
Particles of Surfaces 7: Detection, Adhesion and Removal pages:69-95
7th International Symposium on Particles on Surfaces location:Newark, NJ date:19-21 June 2000
In the development of wet cleaning processes for removal of submicrometer particles from semiconductor wafer surfaces attention is often paid to the cleaning chemistry alone. However, the subsequent rinsing and drying steps can be equally important. In this work some important issues in this area are illustrated by means of a case study. This study covers the removal of abrasive residues from a copper Chemical Mechanical Polishing (CMP) process by a wet etching mechanism. The main focus of this work is on the behavior of alumina based slurry after cleaning in an HF based chemistry. The surface after a CMP step is heterogeneous in nature, consisting of adjacent areas of different materials, in this case, e.g., copper and oxide. In the subsequent post-CMP cleaning step numerous particles, often residues from the abrasive in the polishing slurry, have to be removed.