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提出了用单频导纳谱法测量储硅单量子阶的能带偏移，与常规的多频导纳谱相比，它只需测一个频率的导纳谱就能得到更精确的实验结果。用该方法对Ｓｉ／Ｇｅ＿（０．３３）Ｓｉ＿（０．６７）／Ｓｉ单量子阱进行测试，得到激活能为Ｅ＝０．２０ｅＶ。为了计算出能带偏移值，必须能准确确定具有单量子阱结构样品中的费密能级位置，由于在单量子阱结构中费密能级的位置与阱材料、垒材料的掺杂浓度、阱的高度（即能带偏移）及温度等几个因素均有关。为此，本文通过解泊松方程，计算出结合本文样品参数的具体单量子阶能带图及费密能级位置。计算结果表明，费密能级位于阱材料的禁带之内，Ｅ＿Ｆ－Ｅ＿（Ｖ１）＝０．０４ｅＶ．由于单量子阱两边的载流子向阱内转移，使阱中平均载流子浓度（２×１０￣（１７）ｃｍ￣（－３））比掺杂浓度（１×１０￣（１６）ｃｍ￣（－３））要大一个数量级。并使界面附近阱和垒的能带发生弯曲，其分别为０．００６和０．１１ｅＶ，由此计算出的价带偏移为０．１６ｅＶ。通过理论模拟计算的结果表明，单频导纳谱的方法是切实可行的。
A single-frequency admittance spectroscopy method is proposed to measure the band offset of a single-order silicon-based storage silicon. Compared with the conventional multi-frequency admittance spectroscopy, it can obtain more accurate experimental results by simply measuring the admittance spectrum of one frequency . The Si / Ge_ (0.33) Si_ (0.67) / Si single quantum well was tested by this method and the activation energy was E = 0.20eV. In order to calculate the band offset value, the position of Fermi level in the sample with a single quantum well structure must be accurately determined. Since the position of the Fermi level in the single-quantum well structure is different from that of the well material and the dopant concentration of the barrier material , Well height (ie, band offset) and temperature and other factors are related. To solve this problem, we solve the Poisson’s equation and calculate the specific single-order energy band diagram and Fermi level position in the paper. The calculated results show that the Fermi level lies within the forbidden band of the well material, E_F-E_ (V1) = 0.04eV. The average carrier concentration (2 × 10 ~ (17) cm ~ (-3)) in the well is lower than that of the doping concentration (1 × 10 ~ (16) cm ~ (-3)) to an order of magnitude larger. And the energy bands of the wells and barriers near the interface are warped to 0.006 and 0.11 eV, respectively, and the valance band offset calculated is 0.16 eV. The theoretical simulation results show that the single-frequency admittance spectrum method is feasible.