离子束刻蚀HgCdTe环孔pn结I—V、RD—V特性的研究（上）

本文推导了一种可简便、准确、直观计算和分析pn结I-V特性的公式和方法,并应用该方法对两类典型HgCdTe环孔pn结的I-V、RD-V特性进行了计算和拟合;得到了表面欧姆(反型沟道)漏电导、二极管理想因子n随电压的分布等反映二极管结特性的重要参数.计算结果表明,对于长波HgCdTe光伏器件而言,表面漏电流在整个暗电流中所占的比重相当大,表面漏电流严重地制约着器件性能.HgCdTe材料的晶体缺陷会使二极管的理想因子n增大,从而使产生-复合电流及陷阱辅助隧穿电流增加.

Study of I-V and RD-V Characteristics of Ion Beam Milling HgCdTe Loophole pn Junction

In this paper, a simple, accurate and intuitionistic formula and method for calculating and analyzing the I-V characteristics of a pn junction is deduced. The method is used to calculate and analyze the I-V and RD-V characteristics of two typical HgCdTe loophole junctions. Some important parameters which reflect the characteristics of a diode, such as surface Ohm leakage conductance and the distribution of the ideal factor n with voltage are obtained. The calculation result shows that for a long wavelength HgCdTe photovoltaic device, the surface leakage current accounts for a significantly large amount of the total dark current and imposes a severe restriction on the performance of the device. Due to the crystal defect in HgCdTe material, the ideal factor n of the diode can be increased and hence both the generation-recombination current and the trap-assisted tunneling current can be increased.