摘要
在10K至292K温度范围内测量了GaAs/GaAlAs多量子阱结构的激子吸收谱.观察到轻、重空穴对应的激子吸收峰(LH和HH)及台阶状态密度.研究了轻、重空穴激子吸收峰的能量间隔及激子吸收峰的温度特性.发现多量子阱样品的LO声子展宽系数为6.1meV,比体GaAs的展宽系数略小.样品用国产MBE设备生长,采用化学选择腐蚀技术除去GaAs衬底.
The exciton absorption spectra of GaAs/GaAlAs MQW structures at temperatures between10k to 292k are measured.The exciton absorption resonaces (HH and LH) and step accumu-tive density Of state have been observed. The energy differences between light hole and heavyhole exciton absorption resonaces have been investigated. We also investigated the temperaturedependenc of the linewidth of HH exciton absorotion resonace.The LO phono broadenningconstant Fb in our sample is 6.1 meV which is smaller than that of the bulk GaAs, TheGaAs/GaAlAs MQW structures of 120 periods are grown on [100] oriented Cr-doped GaAs su-bstrate by MBE in the institute of semiconductors of chinese Academy of sciences.The GaAssubstrate is removed by selective chemical etching,leaving the MQW structures exposed over1mm^2 area.
