Development of III-V barrier diode radiation-hard infrared detectors for space applications

Opto-electronic devices destined for space must be suitably radiation-hard, meaning that they must be resilient to the effects of high energy radiation in space. For high performance IR (infrared) space-based applications, the current material of choice is MCT (Mercury Cadmium Telluride). MCT is difficult and therefore expensive to fabricate and the constituent materials are becoming increasingly restricted by regulation. The new generation of barrier diode detectors based on III-V materials offer a promising alternative to MCT, providing comparable performance whilst offering devices that are compatible with volume manufacturing processes. As part of a DASA Space-to-Innovate Phase 1 funded project we have developed a novel radiation hard unipolar barrierbased ABaT™ III-V MWIR diode detector. The detector is being subjected to gamma and proton radiation testing to demonstrate its suitability for space environments. To compare the radiation performance of this diode, a number of other typical III-V detector diode structures have been fabricated and tested. In this paper we present the results of the project so far and future plans to develop this into detector arrays.