Abstract As the improvement in efficiency of CdTe solar cell becomes more and more difficult, it is very necessary to engage in research on CdTe solar cell with innovative structure or new materials. In this work, we first proposed a design idea of constructing cadmium telluride on silicon to form a CdTe/Si composite absorption layer and then achieving an innovative high efficiency solar cell with a basic structure of n-Zn1-xMgxO/p-CdTe/p-Si/Au. This kind of solar cell has the advantages of relatively high open-circuit voltage and large short-circuit current, because photons with a wavelength range of 825 nm–1100 nm can not be absorbed by CdTe with a bandgap of 1.5 eV while they can be absorbed by silicon with a bandgap of 1.12 eV, thereby extending the long-wave response of sunlight. Numerical simulation of solar cell was carried out by using SCAPS-1D software to study the impacts of materials parameters such as thickness, doping concentration, valence band offset (VBO) and interface state density of CdTe/Si on device performances. Results indicated that thinner CdTe and suitable thick Si were beneficial for the cell with high efficiency. Particularly, the interface states between CdTe and Si severely degraded cell performance, so an innovative CdSixTey layer was proposed for the first time to effectively reduce the lattice mismatch and modify the interface properties between CdTe and Si. Finally, the highest theoretical conversion efficiency of 28.36% accompanied by open-circuit voltage of 0.838 V, short-circuit current of 39.28 mA/cm2, and fill factor of 86.11% of solar cell with SnO2:F/Zn1-xMgxO/CdTe/CdSixTey/Si/ZnTe:Mo/Au structure was obtained by optimizing numerical simulation design.

中文翻译：

---

具有 CdTe/Si 复合吸收层的创新型高效太阳能电池的数值模拟

摘要 随着碲化镉太阳能电池效率的提高变得越来越困难，对具有创新结构或新材料的碲化镉太阳能电池进行研究是非常必要的。在这项工作中，我们首先提出了在硅上构建碲化镉形成 CdTe/Si 复合吸收层的设计思路，然后实现了具有 n-Zn1-xMgxO/p-CdTe/p 基本结构的创新型高效太阳能电池。 -Si/Au。这种太阳能电池具有较高的开路电压和较大的短路电流的优点，因为波长范围为 825 nm-1100 nm 的光子不能被带隙为 1.5 eV 的 CdTe 吸收，而可以被 CdTe 吸收。被带隙为 1.12 eV 的硅吸收，从而扩展了太阳光的长波响应。利用SCAPS-1D软件对太阳能电池进行数值模拟，研究了厚度、掺杂浓度、价带偏移(VBO)和CdTe/Si界面态密度等材料参数对器件性能的影响。结果表明，较薄的 CdTe 和合适的厚 Si 有利于电池的高效率。特别是 CdTe 和 Si 之间的界面态严重降低了电池性能，因此首次提出了一种创新的 CdSixTey 层，以有效减少晶格失配并改变 CdTe 和 Si 之间的界面特性。最后，最高理论转换效率为 28.36%，开路电压为 0.838 V，短路电流为 39.28 mA/cm2，填充因子为 86.11%，SnO2:F/Zn1-xMgxO/CdTe/ CdSixTey/Si/ZnTe：