摘要
针对光伏型中波HgCdTe双色红外探测器作了优化模拟计算,器件采用典型n-p-p-p-n结构和同时工作模式,建立的二维模型考虑了辐射复合、俄歇复合和Shockley-Read-Hall(SRH)复合三种复合机理,以及深能级辅助隧穿和带间直接隧穿效应,载流子穿过阻挡层势垒的隧道效应采用传递矩阵法计算.分析了双色器件光谱响应随吸收区SRH复合少子(电子)寿命的变化关系,以及串音与阻挡层组分的关系.模拟结果显示,随吸收区少子寿命变短,量子效率迅速下降;为了使器件有较高的量子效率,HgCdTe材料的SRH复合电子寿命应该至少在10ns以上.随阻挡层组分增大,势垒增高,串音迅速减小,大约在阻挡层组分差为0.03时下降到光学串音决定的稳定值,得出了抑制电学串音,阻挡层组分差的临界值为0.03.
The performance of two-color middle wavelength photovohaic HgCdTe detector is simulated numerically for design optimization. Three recombination mechanisms （radiation, Auger, and Shockley-Read-Hall（SRH）recombination）, trap-assisted tunneling, and band-to-band tunneling are considered in two-dimensional model. The tunneling through barrier layer is calculated by transfer matrix method. The n-p-p-p-n structure is designed in simultaneous mode. The effect of SRH recombination electron lifetime in p-region on spectral response is examined, and the dependence of crosstalk on composition gradient of barrier layer is analyzed. Simulation results show that the quantum efficiency decreases rapidly with decrease of SRH electron lifetime in p-region, and at least about 10ns of SRH electron lifetime is essential for good performance of the detector. Crosstalk decreases to the steady value determined by optical crosstalk as the composition gradient of barrier layer increases to about 0.03, so critical composition gradient of about 0.03 is necessary for suppressing the electrical crosstalk.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2007年第5期2882-2889,共8页
Acta Physica Sinica
基金
国家重点基础研究发展规划项目(批准号:2004CB619004)
国家自然科学基金(批准号:10234040
60244002)资助的课题~~
关键词
HgCdTe中波双色红外探测器
光谱响应
光谱串音
少子寿命
HgCdTe middle wavelength two-color infrared detector, spectral response, spectral crosstalk, minority carrier lifetime
