Preparation of single crystalline regions in amorphous silicon layers on glass by Arq laser irradiation

By melting amorphous silicon layers on glass by the beam of an Arq laser, large grained polycrystalline films as well as single crystalline regions at predefined positions were generated. If the layers are crystallized by scanning a circular laser beam at a rate of up to 5 cmrs the crystal size depends on the overlap between successive scanning traces. The lateral dimensions of the crystals exceed several 10 mm for an overlap slightly above 50%. Crystals with size dimensions of about 100 mm were produced by line scanning of a focused laser beam. Large single crystals were obtained by scanning a sickle-shaped or L-shaped beam profile. If the laser is switched on and off repeatedly, single crystalline regions are produced at predefined positions. q2000 Published by Elsevier Science B.V. All rights reserved.