砷掺HgCdTe长波红外光电二极管阵列的制备与性能

采用砷(As)掺杂HgCdTe材料研制了响应截止波长为12.5 μm,规格为256×1的长波红外光电二极管阵列.实验设计了一种新的pn结测量方法,测量发现砷掺长波HgCdTe材料离子注入形成pn结深度在3.6～5.3 μm之间,而其最大横向尺寸大约是设计尺寸的1.3倍.实验采用一种改进的表面处理工艺制备了砷掺HgCdTe长波红外光电二极管阵列,获得了良好的电学性能,该工艺与常规表面处理工艺相比可以使器件峰值阻抗提高2个量级,而-0.5v偏压下的动态电阻可提高约30倍.研究认为,器件性能提高的原因是由于改进工艺可以有效抑制器件表面漏电流.

Fabrication and performances of arsenic-doped HgCdTe long-wavelength infrared photodiode arrays

Long-wavelength (λc~12.5 μm) 256×1 infrared photodiode arrays based on liquid phase epitaxy (LPE) grown arsenic-doped HgCdTe were fabricated. The performances of the devices were investigated in this work. The profile of implanted pn junction on arsenic-doped HgCdTe was determined by a novel method. The results show that the junction depth is about 3.6~5.3 μm and the largest lateral size is about 130% of the designed value. In the experiment, HgCdTe long-wavelength photodiode arrays were fabricated by traditional and modified surface processing techniques. The modified process can improve the electrical properties of the devices significantly. The peak resistance and dynamic resistance at-05 V in the R-V curves of the devices by modified process is about 100 and 30 larger than those of the devices by traditional process, respectively. The reason of the improvement is assumed to be the suppression of surface leakage current.