FORMATION OF LUMINESCENT SILICON BY LASER ANNEALING OF A-SIH

We report the preparation of luminescent Si by laser annealing of amor phous hydrogenated silicon (a-Si:H) deposited on a silica substrate by glow-discharge deposition. For this process, we have used XeCl excime r laser pulses with an energy density in the range of 0.3-0.7 J/cm2. W hile no visible photoluminescence (PL) has been observed at room tempe rature from the unirradiated a-Si:H the PL comparable to the PL spectr a of porous Si occurs in the irradiated part. The electron microscope studies reveal a microstructure which is a function of the pulse numbe r and the pulse energy density.