InGaN单结太阳电池中的浅能级杂质的理论计算和模拟

通过氢有效质量理论(HEMT)对In0.65Ga0.35N(高In组分,Eg=1.31eV)太阳电池材料进行分析,计算出其浅能级施主和受主的重要性质参数电离能:ΔED～10.8meV,ΔEA～90meV.在此基础上得到了室温条件下In0.65Ga0.35N的浅能级施主和受主强电离时的杂质浓度范围:施主9.56×108～4.57×1016cm-3,受主9.56×108～7.84×1016cm-3;并估算了产生杂质能带的最低杂质浓度:施主～1×1018cm-3,受主～5.79×1020cm-3.然后借助AMPS-1D软件对含有部分电离的浅能级施主、受主In0.65Ga0.35N单结太阳电池进行模拟,详细讨论了施主能级和受主能级对载流子的俘获对太阳电池效率的影响.本文结果为InGaN单结和多结太阳电池的掺杂(尤其是p型掺杂)和制备提供了理论参考和帮助。

Theoretical calculation and simulation of shallow dopants in InGaN single junction solar cell

Hydrogenic effective-mass theory (HEMT) was adopted to study the photovoltaic property of In_0.65Ga_0.35N (E^g=1.31 eV). The ionization energy of shallow donors and acceptors in In_0.65Ga_0.35N was calculated to be ?E_D ~10.8 meV and ?E_A~90 meV, respectively. Based on these values, the doping concentration necessary to obtain strong ionization of shallow dopants was estimated to be 9.56×10⁸–4.57×10¹⁶ cm^–3 for donors and 9.56×10⁸–7.84×10¹⁶ cm^–3 for acceptors. The lowest doping concentration required to form impurity bands was found to be ~1×10¹⁸ cm^–3 for donors and ~5.79×10²⁰ cm^–3 for acceptors. Using AMPS-1D software, the property of single junction solar cell containing partially ionized shallow dopants, was simulated. The effects of recombination of shallow dopants on the efficiency of the solar cell were analyzed and discussed in detail. The results are useful for doping (especially for p-type doping) and fabrication of InGaN-based single junction and multijunction solar cells.