【摘要】 本文报道了Ga_1-xAl_xAs/GaAs电池正向暗I—V特性,示出暗I—V曲线,I₀₁、I₀₂、A₁、A₂及扩展区少子有效扩散长度等计算值。确定了以复合电流为主要暗电流的电流输运机理。用双指数模型讨论了暗特性和输出特性的关系。获得了开路电压V_oc随I₀₂降低而提高,填充因子FF随A₂的降低而增加的实验结果。EB1C扫描照片示出GaAs电池的有源区中存在无数不规则黑区,单束感生电流在这些区域明显减弱。电子探针测出黑区为Fe、Si、Al的杂质团。非火焰原子吸收光谱测出GaAs衬底中含有4×10¹⁵cm^-3的杂质铁。铁、硅杂质团是影响少子扩散长度和复合电流的主要因素。 通过改进工艺,降低了暗电流,提高了电池性能,V_oc（1.01-1.05）超过理论预期值,FF（0.81-0.82）达到理论预期值,转换效率（AM1）达18—19％。更多还原

【Abstract】 In this paper forward Ⅰ-Ⅴ characteristics were determined to identify the dominat current mechanisms and to calculate I01, I02, A1, A2 and the effective carrier lifetimes in the deplation region. Results show that the Voc and FF increase with the decreasing of I02 and A2 respectively.A number of dark region can be observed in EBIC determination where the induced current decreased dratically. The Electron prob analysis shows that the Fe, Si, Al impurity clusters are found in the p-GaAs region. Fe in GaAs substrate with concentration of 4×1015cm-3 is determined by flameless atomic adsorption spectropho-tometry.Having studied the junction characteristics a new procedure was developed for the preparation of the solar cell. High conversion efficiency of 18-19% at AM1 with a high Voc 1.01-1.05 and a high FF 0.81-0.82 were obtained together with the reduction in dark current and increasing in the effective minority lifetime.更多还原