Si衬底掺杂浓度对InGaN/Si异质单结太阳电池性能的影响

Effects of Si Substrate Doping on the Performances of InGaN/Si Heterojunction Solar Cells

关键词:  异质结  InGaN薄膜  太阳电池  AMPS-1D

Key words:  heterojunction  InGaN films  solar cells  AMPS-1D

摘要:

[目的]研究p-Si衬底掺杂浓度对InGaN/Si异质单结太阳电池性能的影响,为制备高效太阳电池提供理论基础。[方法]将器件的n-InGaN掺杂浓度固定为10¹⁶ cm^-3,在改变p-Si衬底掺杂浓度N_A的情况下,采用一维光电子和微电子器件结构分析模拟软件(AMPS-1D)对InGaN/Si异质单结太阳电池器件的各项性能参数进行模拟。[结果]随着掺杂浓度N_A的升高,电池的电流密度J_SC和填充因子FF随之升高,当到达一定高的掺杂浓度范围时(N_A>5.00×10¹⁷cm^-3),J_SC基本保持不变,约为28.12 mA/cm²,FF保持在0.85左右且变化不大。开路电压V_OC和光电转换效率E_ff与掺杂浓度的大小呈正相关关系,随着N_A的增大,V_OC、E_ff缓慢增大。[结论]高掺杂浓度下的太阳电池具有较好的光电转换效率。低掺杂浓度的太阳电池光电转换效率较低,这是因为其对应的尖峰势垒高度和宽度均较大,影响了光生载流子的输运。

Abstract:

[Objective] In order to provide a theoretical basis for the preparation of high efficiency solar cells, the effects of doping concentration of p-type Si on the performances of InGaN/Si heterojunction solar cells was studied.[Methods] In this paper, the n-type InGaN doping concentration was fixed at 10¹⁶cm^-3 when the doping concentration N_A of p-type Si substrate varied, then the results of the current density J_SC,the open circuit voltage V_OC, the filling factor FF, and the photoelectric conversion efficiency E_ff of the InGaN/Si heterojunction solar cell device could be obtained by using a one-dimensional device simulation program for the Analysis of Microelectronic and Photonic Structures (AMPS-1D).[Results] With the increase of the doping concentration N_A,the current density J_SC and the filling factor FF increased. When the doping concentration reached a certain range (N_A>5.00×10¹⁷cm^-3),J_SC basically unchanged,about 28.12 mA/cm², FF remained around 0.85 and did not change much. The open circuit voltage V_OC and the photoelectric conversion efficiency E_ff both had a positive correlation with the doping concentration N_A.As the NA increased, the V_OC and E_ff increased slowly.[Conclusion] The solar cells with higher doping concentration of Si substrate had better photoelectric conversion efficiency. Those with lower doping concentration had lower efficiency, because their corresponding peak height and width of potential barrier were large,affecting the transport of photo-generated carriers.