IN-SITU EXCIMER LASER ANNEALING OF LOW-TEMPERATURE LPCVD GROWN POLYCRYSTALLINE SILICON: INFLUENCE OF METAL DIFFUSION ON THE FILM MORPHOLOGY AND ON THE GROWTH RATE

摘要

Polycrystalline silicon films have been grown from Si_2H_6 by Low-Pressure Chemical Vapour Deposition (LPCVD) at 800K and in-situ laser annealing on amorphous silicon seed layers deposited on a metallic Ti/Pd/Ag multilayer. The crystalline volume fraction in the seed layer was controlled by thermal annealing. According to the Metal Induced Crystallization (MIC) effect, the presence of the metal induces a lower-temperature crystallizzation of silicon in the seed layers. XRD and SEM data show that the formation of palladium silicides in the seed layer drives the growth of wire-like columns which are found to change morphology depending on the seed layer microstructure and laser annealing parameters. Superficial palladium was found to affect also the growth rate by enhancing the Si_2H_6 dissociation.