摘要
基于二维数值模型,对光伏型中波(MW1/MW2)HgCdTe双色红外探测器作了模拟计算,器件采用n-p-p-p-n结构、同时工作模式.计算了双色器件光谱响应及量子效率,重点分析了两个波段间的信号串音问题,以及高组分势垒层的作用.模拟结果显示,MW1(中波1,波长较短)对MW2(中波2,波长较长)的串音是辐射透过MW1区在MW2区中吸收引起的,串音与光吸收比近似成正比,而载流子扩散效应可以忽略不计.高组分阻挡层对载流子扩散引起的串音有显著的抑制作用,如果没有势垒层,载流子扩散引起的串音十分明显,甚至成为串音的主导因素.对于60×60μm2探测单元MW1和MW2的结电容大约为1.75pF/pixel.
The performance of two-color middle wavelength infrared photovoltaic HgCdTe detector was simulated numerically based on a two-dimensional model. The structure of n-p-p-p-n was designed in simultaneous mode. The spectral response, quantum efficiency, and junction capacitance were calculated, and the crosstalk between two bands and the function of barrier layer were analyzed in detail. The calculation results show that the infrared radiation transmitted through MW1 （shorter wavelength in middle wavelength band） diode can be absorbed in MW2 （longer wavelength in middle wavelength band） diode, and this causes MWI-to-MW2 crosstalk. The crosstalk is linearly depended on the ratio of radiation absorbed in MW2 diode to that in MW1 diode. The barrier layer can remarkably suppress the crosstalk caused by photocarriers diffusion. Without the barrier layer, the MWI-to-MW2 crosstalk will increase as large as 10 times, and is dominated by photocarriers diffusion. The junction capacitance of MW1 and MW2 diode is about 1.75F/pixel for 60 ×60μm^2 detector.
出处
《红外与毫米波学报》
SCIE
EI
CAS
CSCD
北大核心
2007年第3期164-169,共6页
Journal of Infrared and Millimeter Waves
基金
国家重点基础研究发展规划资助项目(2004CB619004)
国家自然科学基金资助项目(10234040
60244002)
关键词
碲镉汞
中波双色红外探测器
光谱响应
串音
结电容
.HgCdTe
two-color infrared detector
spectral response
crosstalk
junction capacitance
