Investigation of the effect of substrate orientation on the structural, electrical and optical properties of n-type GaAs1?xBix layers grown by Molecular Beam Epitaxy

Current-Voltage (I-V), Capacitance-Voltage (C-V), Deep Level Transient Spectroscopy (DLTS), Laplace DLTS, Photoluminescence (PL) and Micro-Raman techniques have been employed to investigate the effect of orientation substrates on structural, electrically optically active defects in dilute GaAs1?xBix epilayers structures having a Bi composition x = ~5.4%, grown by Molecular Beam Epitaxy (MBE) (100) (311)B GaAs planes. X-ray diffraction results revealed that in-plane strain Ga(As,Bi) layer samples (100)-oriented substrate (?0.0484) is significantly larger than (311)B-oriented substrate. The found noticeable impact incorporation electrical properties GaAsBi Schottky diodes. I-V characteristics showed diodes exhibited ideality factor higher barrier height compared with samples. DLTS measurements number traps were different for two orientations. In particular, three electron are detected substrates, respectively, activation energies ranging from 0.12 0.41 eV. Additionally, one hole trap was observed only sample energy 0.24 small attributed pair defects. photoluminescence Raman spectra evidenced compressive which affects considerably optical properties. Furthermore, PL also affected contributions Bi- related agreement results.