Development of sensitive long-wave infrared detector arrays for passively cooled space missions

TL;DR

This paper discusses the development of advanced long-wave infrared detector arrays for space missions like NEOCam, emphasizing their performance at passively cooled temperatures suitable for detecting hazardous near-Earth objects.

Contribution

It reports the successful development and testing of 10 micron cutoff HgCdTe detector arrays with excellent performance metrics at passively cooled temperatures.

Findings

Arrays meet noise, dark current, and quantum efficiency goals

Performance achieved at 35-40 K focal plane temperatures

First arrays demonstrate promising technology readiness

Abstract

The near-earth object camera (NEOCam) is a proposed infrared space mission designed to discover and characterize most of the potentially hazardous asteroids larger than 140 m in diameter that orbit near the Earth. NASA has funded technology development for NEOCam, including the development of long wavelength infrared detector arrays that will have excellent zodiacal background emission-limited performance at passively cooled focal plane temperatures. Teledyne Imaging Sensors has developed and delivered for test at the University of Rochester the first set of approximately 10 micron cutoff, 1024 x 1024 pixel HgCdTe detector arrays. Measurements of these arrays show the development to be extremely promising: noise, dark current, quantum efficiency, and well depth goals have been met by this technology at focal plane temperatures of 35 to 40 K, readily attainable with passive cooling. The next set of arrays to be developed will address changes suggested by the first set of deliverables.