Patent ID: 8278659

Claim:
An apparatus for making a laterally extending crystalline region in a film of semiconductor material on a substrate having at least a surface region comprising a material which is different from said semiconductor material and which is inert with respect to crystal growth in said film, comprising: (a) a pulsed radiation beam source for providing a plurality of radiation beam pulses; (b) a beam homogenizer to homogenize said radiation beam pulses, said homogenized laser pulses each having a substantially predetermined size; (c) a beam mask adapted to receive said plurality of homogenous radiation beam pulses and including a plurality of slits to define respectively a plurality of masked laser beam pulses, each masked laser beam pulse having a shape defined by a length and a width wherein said width being determined by said predetermined slit width and each having an intensity pattern for irradiating said film; (d) a sample translation stage optically coupled to said beam mask, and adapted for holding said substrate while at least a portion of said film is irradiated by said masked laser beam pulses and for translating said substrate in a lateral direction with respect to said masked laser beam pulses from a first position to at least a second position; wherein when said sample translation stage is in said first position, a first portion of said semiconductor film is positioned to be irradiated by a first of said masked laser beam pulses so as to melt said semiconductor material in a first portion throughout its thickness, and when said sample translation stage is in said second position, a second portion of said semiconductor film is positioned to be irradiated by a second of said masked laser beam pulses so as to melt said semiconductor material in a second portion throughout its thickness, and wherein said second portion overlaps said first portion such that at least one semiconductor crystal formed in said first portion as a result of said irradiating in said first position and subsequent solidification is in both said first portion and said second portion.