Deep electron trapping center in Si-doped InGaAlP grown by molecular-beam epitaxy

Abstract

The properties of a deep electron trapping center found in Si-doped In0.51Ga0.49−xAlxP (x=0.24) grown on Si-doped GaAs(100) substrates using molecular-beam epitaxy are studied. The trapping parameters for this center are determined as follows: thermal activation energy 0.48 eV, photoionization energy 1.25 eV, and capture barrier 0.10 eV. The concentration of this center is about seven times as high as that of the shallow donor state and is found to increase with an increasing amount of Si atoms incorporated into the crystal. The thermally activated persistent behaviors of photocarriers are also observed at low temperatures. These results suggest that this center can be regarded as a kind of DX center originally found in AlGaAs, which should be depicted as a state with large lattice relaxation using a configuration coordinate diagram.