Investigation of Growth Mechanism and Role of H_2 in Very Low Temperature Si Epitaxy

摘要

High quality crystalline homoepitaxial silicon film has been deposited in single-step growth using ultra-high vacuum plasma-enhanced chemical vapor deposition at 250°C. An investigation on the effects of key growth parameters such as temperature, hydrogen dilution, and plasma power has led to achievement of balanced growth conditions. Material Characterization reveals that the defect-free growth is due to the dominant role hydrogen plays in enhancing surface diffusion over selective etching of the amorphous phase. Absence of crystal defects, such as dislocations or stacking faults, shows that single-step growth, results in extremely high quality growth at low temperatures.