Development of type II superlattice detector for future space applications at JAXA

The performance of space-borne infrared detectors is required higher sensitivity, higher resolution, or larger format in comparison with that of ground-based infrared detectors. In order to realize higher mission requirements, JAXA decided to position the infrared detector technology as one of the strategic technologies of JAXA and to promote the development of the infrared detectors. InAs/GaSb Type II superlattice (T2SL) is the only known infrared material that has a theoretically predicted higher performance than HgCdTe. If the T2SL detector is realized, it can be applied for high sensitivity infrared sensors, which are required for many advanced instruments such as an imaging Fourier Transform Spectrometer. The final goal of the T2SL detector development is to realize an array detector having a cutoff wavelength of lc=15mm. We have started a basic research on the T2SL detector. In this paper, we report on the first results of the development of T2SL detectors of mid-wave infrared regime. The detector structure is a pin photodiode with SL of 9 InAs monolayers (MLs) and 7 GaSb MLs. We present results of optical evaluation of the detector. The cutoff wavelength is 5.5mm at 30K. The responsivity is 0.33±0.05A/W at 4.5 mm.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.