Patent ID: 7704862

Claim:
A system for reducing a surface roughness of a polycrystalline or single crystal thin film produced by the sequential lateral solidification process, comprising: (a) an excimer laser for generating a plurality of excimer laser pulses of a predetermined fluence; (b) an energy density modulator, optically coupled to said excimer laser, for controllably modulating said fluence of said excimer laser pulses emitted by said excimer laser such that said fluence is below that which is required to completely melt said polycrystalline or single crystal thin film; (c) a beam homoginizer, optically coupled to said energy density modulator, for homogenizing said modulated laser pulses in a predetermined plane; (d) a sample stage, optically coupled to said mask, for receiving said homogenized laser pulses to effect partial melting of portions of said polycrystalline or single crystal thin film corresponding to said laser pulses; (f) translating means, coupled to said sample stage, for controllably translating a relative position of said sample stage with respect to said laser pulses; and (g) a computer, coupled to said excimer laser, said energy density modulator, and said translating means, for controlling said controllable fluence modulation of said excimer laser pulses and said controllable relative positions of said sample stage and said laser pulses, and for coordinating said excimer pulse generation and said fluence modulation with said relative positions of said sample stage and said laser pulses, to thereby process said polycrystalline or single crystal thin film by sequential translation of said sample stage relative to said laser pulses at corresponding sequential locations thereon.