A theory for image persistence in HgCdTe photodiodes

被引：43

作者：

Smith, Roger M. ^{[1
]}

Zavodny, Maximilian ^{[1
]}

Rahmer, Gustavo ^{[1
]}

Bonati, Marco ^{[2
]}

机构：

[1] CALTECH, Caltech Opt Observatories, MC105-24,1200 E Calif Blvd, Pasadena, CA 91125 USA

[2] Cerro Tololo Interamer Observ, La Serena, Chile

来源：

HIGH ENERGY, OPTICAL, AND INFRARED DETECTORS FOR ASTRONOMY III | 2008年 / 7021卷

关键词：

persistence; remnant image; HgCdTe; 1.7 mu m cutoff; depletion region; charge traps;

D O I：

10.1117/12.789372

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

Image persistence, an elevated dark current caused by prior illumination, has been a chronic problem in near infrared focal plane arrays. It has the potential to interfere with astronomical surveys requiring precision photometry, astrometry and/or shape measurement. We posit a mechanism whereby charge is captured by traps exposed to carriers as the depletion width shrinks when photo-generated charge accumulates on the electrically isolated photodiode. After the depletion width is reestablished by resetting the diode, trapped charge is slowly released, appearing to be a signal during the subsequent exposure(s). We present data illustrating the complex behavior of persistence for several 1.7 mu m cutoff HgCdTe arrays on Teledyne H2RG multiplexers, and show that our simple model predicts this behavior at least qualitatively. We identify one inconsistency that has yet to be resolved and discuss mitigation options.

引用

页数：12