Patent ID: 6300176
Filing Date: 2001-10-09
Classification: B23K,H01L

Abstract:
A method of manufacturing a semiconductor device comprising the steps of:emitting a first laser beam from a laser device at an output energy;attenuating said first laser beam by using at least one light attenuating filter;condensing said first laser beam by an optical system;first scanning a semiconductor layer formed over a substrate with the condensed first laser beam for annealing said semiconductor layer,wherein an energy of said first laser beam applied to said semiconductor layer is lower than an output energy range that allows said laser device to operate most stably, andemitting a second laser beam from said laser device, said second laser beam having same output energy as said first laser beam;condensing said second laser beam by said optical system; andsecond scanning said semiconductor layer with the condensed second laser beam for annealing said semiconductor layer,wherein the energy of the first condensed laser beam is 150-250 mJ/cm.sup.2 and the energy of the second condensed laser beam is 200 to 380 mJ/cm.sup.2,wherein the energy of said condensed second laser beam applied to said semiconductor layer is higher than that of said condensed first laser beam.