Diagnostics of laser-induced germanium growth by in situ spectroscopic ellipsometry

Nucleation and growth of high quality amorphous hydrogenated germanium (a-Ge:H) films was initiated by ArF laser-induced CVD and monitored in situ by real time spectroscopic ellipsometry. The UV-laser power was varied between 3 W and 10 W. The depositions were carried out at low partial pressures of digermane from 0.05 /spl mu/bar to 6 /spl mu/bar, chamber pressures between 0.5 mbar and 12 mbar and substrate temperatures between 250/spl deg/C and 310/spl deg/C. The influence of the deposition parameters such as substrate temperature, laser power, digermane partial pressure and total pressure in the deposition chamber on the growth rate and the film properties was investigated in detail. Typical deposition rates were in the nanometer per minute range.