The enhanced optical property of chemical passivated n type GaSb
In the paper, Te-doped n type GaSb was passivated by (NH4)2S, the optical and surface properties of passivated GaSb were investigated by PL and AFM. After passivation treatment, the luminescence intensity of GaSb was enhanced. The passivation time would also affect luminescence intensity and the surface smooth of GaSb.
Effects of H2S adsorption on surface properties of GaAs {100} grown in situ by MBE
We report here results dealing with the effects of H2S adsorption on crystallographic and electronic surface properties of GaAs {100} layers grown in situ by molecular beam epitaxy (MBE). The adsorption was studied by AES, LEED and ELS. At room temperature, the adsorption is found to be very dependent on the electron irradiation, whereas this effect vanishes at 700 K. This behavior indicates that the mechanism of adsorption is temperature dependent: H2S is adsorbed mainly in molecular form at low temperature (300 K) and in dissociated form at higher temperature (700 K). Adsorption of the molecular form leads to a disordered layer, whereas the dissociative adsorption process induces a (2×1) reconstruction of the GaAs surface near the saturation coverage. This structural reordering is also associated with changes observed in the loss spectra. Moreover, Auger measurements indicate that it is characterized by significant changes in arsenic and gallium lines: it is most likely that the (2×1) structure correspo...
Photoluminescence studies in bulk gallium antimonide
A detailed analysis of Photo Luminescence spectroscopy (PL) on undoped and Te- and Zn-doped samples of high-quality GaSb is presented. Temperature variations of PL peak position and intensity have been used to find the origin of various transitions. The PL peaks of undoped samples have been assigned to unintentional impurities, native defects and excitons bound to the defect. The zinc- and tellurium-related peaks have been identified and the effect of doping concentration on their position and PL efficiency have been studied.