Anisotropic Plasma Chemical Vapor Deposition of Copper Films in Trenches

摘要

An ion-assisted chemical vapor deposition method by which Cu is deposited preferentially from the bottom of trenches (anisotropic CVD) has been proposed in order to fill small via holes and trenches. By using Ar + H_2 + C_2H_5OH[Cu(hfac)_2] discharges with a ratio H_2 / (H_2 + Ar) = 83%, Cu is filled preferentially from the bottom of trenches without deposition on the sidewall and top surfaces. The deposition rate on the bottom surface of trenches is experimentally found to increase with decreasing its width.