An Acid-Based Electroless Cu Deposition Process: Chemical Formulation, Film Characteristics and CMP Performance

摘要

In this study, we developed an acid-based electroless Cu deposition system employing CuCl2-HNO3 chemistry in a HF-NH4F buffer solution. With the help of nitric acid, Cu can be deposited on Si/Ta/TaN substrate without the insertion of a Cu seed layer. The deposition rate is found to decrease with increasing [HNO3] in the solution as shown in Fig. 1.