Growth Kinetics of Copper Films from Photoassisted CVD of Copperacetylacetonate

Abstract
Copper thin films have been deposited by thermal decomposition of copper acetylacetonateoxygen mixtures. Copper films of high quality as observed by Auger Electron Spectroscopy (AES) have been obtained at temperatures as low as 300°C. Under UV illumination, this temperature threshold decreased down to 225°C. The influence of substrate temperature and layer thickness on film roughness as observed by Atomic Force Microscopy is discussed. The kinetics of Cu(acac)₂ decomposition has been investigated as a function of precursor partial pressure and substrate temperature in the range of 200- 350°C, and the maximum deposition rate of 25 Å/min has been reached in the mass transport regime at a substrate temperature of 350°C and a precursor partial pressure of 0.04 Torr. The deposition rate could be substancially enhanced by UV photoassistance.