STUDY OF THE LASER IRRADIATION OF GAAS-GAALAS MULTIQUANTUM WELLS STRUCTURE

We have studied the effects produced by the laser irradiation, with 35 5 nm, photons on a heterostructure made of three independent GaAs/Ga0. 67Al0.33As quantum wells, By comparing the luminescence of the three-q uantum wells before and after the laser irradiation for different dura tions and fluence values one could determine if each of the quantum we ll has been altered or not. Then we achieved complementary observation s of the irradiated multi-quantum wells structures, using both scannin g and transmission electron microscopy, We came to the conclusion that the alteration of the multi-quantum wells structure results from two main effects: the laser ablation effect and the thermal diffusion effe ct.