Study of radiation-induced effects in GaAs(O):Cr under 2 Mev electron irradiation using Raman, FTIR and Hall effect measurements
Abstract
Abstract The GaAs(O):Cr sample was irradiated with 2 MeV electrons at fluences of 1 × 10 17 , 2 × 10 17 and 3 × 10 17 e cm −2 using an electron accelerator. In the Raman scattering spectrum of the as-grown sample, characteristic Raman peaks were observed at 267 and 290 cm −1 . After electron irradiation, a redshift of these peaks was detected, indicating the accumulation of radiation-induced defects and internal stress. Fourier-transform infrared (FTIR) spectroscopy revealed the presence of local vibrational modes in GaAs(O):Cr at 578, 620, 717, 733, 758, 815, and 946 cm −1 . The observed redshift of these peaks indicates the effect of radiation-induced defects on the local vibrational properties of GaAs(O):Cr. Hall effect measurements demonstrated that electron irradiation leads to a decrease in carrier concentration and an increase in mobility, depending on the electron fluence, within the temperature range of 100–300 K.