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用导纳谱技术研究了两类Ｓｉ基量子阱样品基态子能级的性质．基于量子阱中载流子的热激发模型，从导纳谱中得到的激发能值被认为是阱中重空穴基态位置到阱顶的距离．对于ＳｉＧｅ合金和Ｓｉ形成的组分量子阱，主要研究了退火对重空穴基态子能级的影响．发现样品的退火温度为８００℃时，随退火时间延长，激发能增加．对此现象的解释是，由于Ｓｉ，Ｇｅ互扩散，导致界面展宽，量子限制效应降低，重空穴基态位置下降，从而激发能增加．９００℃下退火，由于扩散系数增大和应变弛豫加强，激发能值单调下降，量子限制效应引起的变化被掩盖．对于Ｂ高浓度超薄层掺杂形成的量子阱结构样品，观察到在掺杂层掺杂浓度不变情况下，掺杂厚度的增加会导致量子阱中基态子能级位置下降，从而导致载流子激发能增加．
The properties of the ground states of two kinds of Si-based quantum wells were studied by admittance spectroscopy. Based on the thermal excitation model of the carrier in the quantum well, the excitation energy obtained from the admittance spectrum is considered as the distance from the ground position of the heavy hole in the well to the top of the well. For the quantum well formed by SiGe alloy and Si, the effect of annealing on the ground-state sub-level of heavy-hole is mainly studied. When the annealing temperature was found to be 800 ℃, the excitation energy increased as the annealing time prolonged. The explanation for this phenomenon is that due to the interdiffusion of Si and Ge, the interface broadens, the quantum confinement effect decreases, and the ground state of heavy cavities decreases. As a result, the excitation energy increases. Annealed at 900 ℃, the excitation energy decreases monotonically due to the increase of diffusion coefficient and strain relaxation, and the change caused by the quantum confinement effect is covered up. For the quantum well structure samples formed by the doping of the high-concentration ultra-thin layer B, it is observed that with the doping concentration of the doping layer unchanged, the increase of the doping thickness will lead to the drop of the ground state sub-level in the quantum well, The excitation energy of the flow increases.