Temperature distributions induced by laser pulses in an absorptive semiconductor film deposited on a non absorptive substrate have been calculated. For cases of a Si:H film and a Si:H/ a SiN x: H  multi quantum well structure on the quartz substrates irradiated by the KrF pulsed excimer laser, we analyzed the effect of film thickness, laser energy density and the ratio of sublayers′ thicknesses of a Si:H/ a SiN x: H  MQW structure on the temperature distribution and crystallization of a-Si:H and a-Si:H/a-SiNx:H MQW structure.