Characterization of a 15-μm cutoff HgCdTe detector array for astronomy

Abstract

The University of Rochester infrared detector group is working together with Teledyne Imaging Sensors to develop HgCdTe 15 µm cutoff wavelength detector arrays for future space missions. To reach the 15 µm cutoff goal, we took an intermediate step by developing four ∼13 µm cutoff wavelength arrays to identify any unforeseen effects related to increasing the cutoff wavelength from the extensively characterized 10 µm cutoff wavelength detector arrays developed for the NEOCam mission. The characterization of the ∼13 µm cutoff wavelength HgCdTe arrays at the University of Rochester allowed us to determine the key dark current mechanisms that limit the performance of these HgCdTe detector arrays at different temperatures and bias when the cutoff wavelength is increased. We present initial dark current and well depth measurements of a 15 µm cutoff array which shows dark current values two orders of magnitude smaller at large reverse bias than would be expected from our previous best structures.

Mid-infrared detector development for the Origins Space Telescope

“…The results for 13-μm cutoff wavelength detector arrays were very promising with dark currents, well depths, and operabilities [23][24][25] similar to those of the earlier 10-μm cutoff wavelength detector array produced for NEOSM. For the 15-to 16-μm cutoff wavelength detector arrays produced in the second half of the UR development program, 26 the dark currents were higher and the well depths were lower than Origins requirements. However, those requirements are set by the needed sensitivity at shorter wavelengths, i.e., it would be possible to use HgCdTe arrays to cover from 2.8 to 16 μm using two or three cut-off wavelength arrays, e.g., 6, 11.5, and 16-μm cut-off wavelength detector arrays, and still meet Origins requirements at each of those bands.…”

MIRECLE: Science Yield for a Mid-IR Explorer-Class Mission to Study Non-Transiting Rocky Planets Orbiting the Nearest M-Stars Using Planetary Infrared Excess

“…Longer-wavelength HgCdTe arrays are now being developed by University of Rochester (UR) infrared detector group and Teledyne Imaging Systems (TIS) in support of the NEO Surveyor mission concept, with long-wavelength cut-offs of 10.5 (McMurtry et al 2016), 13 (Cabrera et al 2019), and now 15 µm (Cabrera et al 2020) now being demonstrated. These devices employed a proprietary design to mitigate quantum tunneling dark currents, and yielded three devices with excellent read noise (∼ 30e − ), QE ≥ 80% in the 6 -12 µm wavelength range (without anti-reflective coating), and reduced expected tunneling dark current behavior.…”

Large Interferometer For Exoplanets (LIFE)

“…On the technical side, missions such as PROBA-3 (Loreggia et al 2018) and Pyxis (Hansen & Ireland 2020, Hansen et al in prep) aim to demonstrate formation-flight control at the level required for interferometry, while the Nulling Interferometry Cryogenic Experiment (NICE) (Gheorghe et al 2020) aims to demonstrate MIR nulling interferometry at the sensitivity required for a space mission under cryogenic conditions. Other developments, such as in MIR photonics (Kenchington Goldsmith et al 2017;Gretzinger et al 2019) and MIR detectors (Cabrera et al 2020), have also progressed to the point where a space-based MIR interferometer is significantly less technically challenging.…”