Study On Irradiation Effects Of GaAs/AlGaAs Multiple Quantum Wells

In this paper the author studied the effects of electron & free electron laser (PEL) irradiation on GaAs/AlGaAs multiple quantum wells. In order to simulate space environment the quantum wells were irradiated with 1 MeV electron beams and doses from 1013/cm2 to 1016/cm2. The relationship between photoluminescence (PL) character of the samples and electron irradiation doses was obtained. The results showed that the intensity of characteristic PL peaks of quantum wells were decreased much but they didn't disappear. PL and OTCS were performed on GaAs/AlGaAs quantum wells irradiated by mid-infrared PEL irradiation for 60 minutes. The experimental results showed that the characteristic PL peak of quantum wells was shifted to longer wavelength (red shift) and the intensity was decreased much after FEL irradiation. The reason was that the FEL irradiation caused the enhancement effects of interdiffusion and led to change the distribution of Al atom in quantum wells. From the analysis of OTCS, extrinsic defects were found after the FEL irradiation. These defects changed the structure of quantum wells.