Proton irradiation effects on InGaAs/InAsSb mid-wave barrier infrared detectors

Abstract

Semiconductor-based mid-wave infrared photon detectors that functionalize space-based imaging systems are susceptible to both cumulative ionization and displacement damage, especially due to proton irradiation. Here, the dark current density and quantum efficiency of a mid-wave infrared detector utilizing a strain-balanced InGaAs/InAsSb superlattice active region are examined as a function of a 63 MeV proton radiation dose. Proton-irradiation is performed in an incremental stepwise dose up to a total ionizing dose of 100 krad(Si) or an equivalent proton fluence of 6.1 × 1011 protons/cm2. All characterization work is conducted with the detectors held at an operating temperature of 130 K throughout the experiment to limit thermal annealing effects. Prior to irradiation, the quantum efficiency of the top-side illuminated device without anti-reflection coating is 59.5%. The quantum efficiency is largely independent of temperature below 150 K, indicative of an electron minority carrier. As irradiation progressed the typical linear increase in inverse quantum efficiency with increasing proton fluence was observed, which led to a quantum efficiency damage factor of 1.12 × 1013 e cm2/ph. This value is shown to be an order of magnitude lower than typically observed in III-V nBn devices and is likely due to the higher mobility of minority electrons in the active region of this device. A full analysis of the characterization results suggests that displacement damage creates a significant population of donor states that modify the doping profile, in addition to Shockley–Read–Hall recombination centers that generally form as a result of proton irradiation.

Auger-limited minority carrier lifetime in GeSn/SiGeSn quantum well

“…The energy imparted into the lattice results in displacement damage that takes the form of vacancy-interstitial pairs, which then potentially diffuse to form more complicated defects or self-annihilate, and the subset of the remaining lattice site defects that behave as SRH recombination centers degrade the material's SRH lifetime. A unit increase in SRH defect concentration imparted by the irradiation dose yields a proportional increase in the SRH recombination rate, which is observed as a linear increase in the reciprocal of the measured minority carrier lifetime when the recombination dynamics are SRH-limited, 23,24 and indeed this is the expected response for Ge as well. 25 TRPL from the GeSn/SiGeSn quantum well is measured after irradiation doses of 0.075, 0.150, 0.375, 0.750, and 1.5 Â 10 12 p þ /cm 2 and plotted in Fig.…”

A detector characterization setup for testing performance under space environmental conditions

“…The main effects of total ionizing dose on photon detectors include an increase of the dark current, changes in the charge transfer efficiency of CCDs, changes in the pixel amplifier gain, and reduced quantum efficiency. [3][4][5] Known total ionizing dose effects on microbolometers include changes in the offset and the noise equivalent temperature difference. 1 The main effects of displacement damage include an increase of the dark current, an increased number of hot spots, increased noise due to random telegraphic signals, reduced responsivity or photo current, and reduced quantum efficiency.…”

Comparative Study of Polarization‐Dependent Conversion Efficiency of GaAs and Si Solar Cells at Oblique Incident Angles Using Surface DLAR Coating of MgF2/ZnSe

“…[20] To increase the detection effectiveness of InGaAs detectors, He et al and Carrasco et al applied antireflection coatings such SiNx. [21,22] YF 3 and ZnS double-layer and multi-layer anti-reflection coatings for HgCdTe detectors were studied by D'souza et al and Saini et al, respectively, using theories and experiments. [23] At the wavelength range of 6-14 μm, De Vita et al achieved a transmission improvement ratio of 28% by depositing a ZnS-based anti-reflection coating on a Si plate.…”

“…applied anti‐reflection coatings such SiNx. [ 21,22 ] YF 3 and ZnS double‐layer and multi‐layer anti‐reflection coatings for HgCdTe detectors were studied by D'souza et al. and Saini et al., respectively, using theories and experiments.…”