Materials Science Forum, Vol.384-3, 291-296, 2002
Mechanism of generation of defects in a semiconductor by pulse laser radiation
Laser created intrinsic defects were studied on the base of new experimental data of laser irradiation of the p-CdTe:Cl/SiO2 Structures by second harmonic of the YAG:Nd (+3) laser (lambda = 530 nm) and on the analyses of the previous works with respect to laser treatment of p-Si, p-InSb. The photo luminescence spectra and IN characteristics in crossed electric (E<150V(.)cm(-1)) and magnetic fields (H=0.1 T) were investigated. It was found that irradiation of the structures of CdTe:Cl / SiO2 lead to creation of the donor centers (LDC). The threshold value for the process to take place was I-th 0.2 MW(.)cm(-2). It was determined that the decrease of recombination velocity S-int of the CdTe:Cl SiO2 interface relative to free surface velocity S-fs. Decrease of the S-int correlates with the increase of the potential barrier near interface due to laser radiation induced the temperature gradient. It was assumed that the mechanism of LDC formation is connected with rise of concentration of interstitial Cd at the interface and aggregation of doping atom Cl with defects V-Cl created by laser.
Keywords:laser irradiation;intrinsic defects;thermal gradient field;laser donor center;photoluminescence spectra