Investigation on the failure of the space HgCdTe detector with long-term storage tests

Abstract

The HgCdTe detector is the core device of the infrared imaging system, its reliability directly restricts the performance of the whole imaging system. For some special applications, it maintains in a non-operating storage state for a long time, it is significant to study its storage reliability. Due to the long lifetime of detectors, most studies have been conducted with accelerated life tests, there is a lack of experimental information concerning the failure of these detectors after longtime storage. In this article, the performance degradation of Hg1-xCdxTe detector with the 127 months long-term storage test is studied. The failure mode and failure mechanism of detectors are investigated through the statistics analysis and optical photomicrography. The results indicate that there are three failure modes, such as low-temperature opening circuit, chip circuit opening, and signal reduction accompanied by increased noise. The main type of failure is in the mode of signal reduction accompanied by increased noise, which is a typical failure mode for long-term storage of HgCdTe detectors. In this typical failure mode, corrosion products are observed near the photosensitive surface in the failure detector, which prove to be a metal product of indium. The long-term storage results can provide data support for accelerating storage test and improve the HgCdTe detectors design.