Mechanism of Cu deposition from Cu(EDMDD)2 using H-assisted plasma CVD

Mechanism of high purity Cu thin film deposition from a new F-free Cu complex, Cu(EDMDD)2 have been studied using H-assisted plasma CVD (HAPCVD). The species of Cu(EDMDD) is the dominant neutral radical dissociated from Cu(EDMDD)2 by electron impact. In situ measurements by Fourier transform infrared (FTIR) spectroscopy show that H atoms are quite effective in removing impurities in Cu films. The simplified version of important surface reaction is Cu(EDMDD) + H→Cu + H(EDMDD). Cu films deposited by HAPCVD have a low as-deposited resistivity of 1.84 μΩ cm and is 20 nm thick in trenches 0.5 μm wide and 2.73 μm deep.