用喇曼光谱测定Ⅲ-Ⅴ族半导体带隙和载流子浓度

用共振喇曼散射研究半导体的能带结构,实验观察了Ga_(1-x)Al_xAs直接带隙单声子和GaP在间接带隙(г_(3v)—X_(3c))附近的双声子共振特性。阐述了由喇曼光谱测量确定Ⅲ—V族半导体的载流子浓度。     

半导体中单声子形变势引起共振喇曼散射(英文)

The resonant Raman scattering by TO1 and TO2 was studied near E0 gap of liquid-phase-epitaxy Ga0.39Al0.81As and Ga0.29Al0.71As samples. In order to tune the energy gap of a semiconductor with respect to a fixed gas laser line, the resonant Raman scattering was performed by means of the variation of the energy gap with the temperature in the sample. According to the quasistatic approximation, the resonant profiles of one-phonon deformation potential scattering were calculated. It was discussed in the microscopic theory that the resonance maxima occured at an energy 1/2hvp higher than the gap energies. These were applied to interpret the experimental data. From these measurements, it was found that the direct energy gap Eg was 2.44eV for Ga0.29As0.71As and 2.31eV for Ga0.39Al0.61As at room temperature.     

N型低阻GaAs单晶的表面势垒高度和表面态密度的变温光伏测定研究

本文报导了应用变温光伏方法无需制作特定样品结构而可以非破坏性地测定N型低阻GaAs单晶的表面势垒高度和表面态密度的研究。结合简并化影响的考虑,所得结果与有关报导一致。