碲镉汞pn结中少数载流子寿命的测量

采用改进的光致开路电压衰退方法测量了不同组分Hg1-xCd，Te光伏探测器中光生少数载流子寿命。激发光源为脉冲YAG激光泵浦的光学参量产生器／放大器形成的可调谐红外脉冲激光器。为了减小结电容和串联电阻的影响，引入稳态背景光照明。用存储示波器记录pn结两端开路状态下的电压变化。从指数衰退的曲线经拟合得到开路电压的衰退时间常数，认为其反映了碲镉汞pn结中光生载流子的寿命。实验结果表明：四种组分的探测器在液氮温度下其少数载流子寿命值范围在18—407ns之间。

Measurement of Minority Carrier Lifetime in HgCdTe p-n Junctions

A modified photo-induced open-circuit voltage decay method has been developed to measure the photo-generated minority carrier lifetime in HgCdTe photovoltaic detectors. The excitation light source is a wavelength-tunable pulsed infrared laser formed by a pulsed YAG laser pumped optical parametric generator/amplifier. A constant background illumination has been introduced to minimize the effect of the junction capacitor and the series resistance. The decay of the photo-generated voltage on a p-n junction has been recorded by a storage oscilloscope. By fitting the exponentially decayed photo-voltage curve, the time constant of the decay has been obtained and is regarded as the photo-generated minority cartier lifetime in the HgCdTe p-n junctions. Our results show that the carrier lifetime is in the range of 18 -407 ns at liquid nitrogen temperature for the measured detectors of four compositions.