Characteristics of laser annealing for amorphous Si films prepared by catalytic chemical vapor deposition and application to fabrication of polycrystalline Si thin-film transistors

摘要

Crystallinity of excimer-laser annealed polycrystalline Si (poly-Si) films using amorphous Si (a-Si:H) precursor films prepared by catalytic chemical vapor deposition (Cat-CVD) is presented. No dehydrogenation process is required for Cat-CVD a-Si:H films because of low H content about 1 at. % even at low-temperature deposition below 300℃. It was confirmed that the crystallinity is improved using a-Si:H precursor films prepared by Cat-CVD in comparison with that using a-Si:H precursor films prepared by plasma-enhanced CVD. Cat-CVD also has the advantages of high-rate and large-area deposition of a-Si:H precursor films. Top-gate type thin-film transistors fabricated using Cat-CVD a-Si:H precursor films show the mobility reaching 230 cm{sup}2/Vs being comparable to those using low-pressure CVD ones.