A Study of Sidewall Effects in HgCdTe Photoconductors Passivated with MBE-Grown CdTe

Abstract

In order to evaluate the effectiveness of CdTe surface passivating layers, HgCdTe photoconductors with and without CdTe sidewall passivation were fabricated. As expected, photoconductors with CdTe sidewall passivation demonstrated significantly higher responsivity in comparison with those without sidewall passivation, indicating the effectiveness of molecular-beam epitaxially (MBE)-grown CdTe as a passivation layer in reducing surface recombination velocity. Characterization of the responsivity differences between photoconductors with and without sidewall CdTe passivation offers a potential method for measuring the interface/surface recombination velocity. This has been demonstrated in this paper by extracting the value of the surface recombination velocity using the Synopsys Sentaurus commercial modeling package to fit experimental responsivity data for fully and partially passivated devices.

The bulk generation-recombination processes and the carrier lifetime in mid-wave infrared and long-wave infrared liquid nitrogen cooled HgCdTe alloys

“…However, it should be mentioned that the applied modelling enables the analysis of the surface g-r processes which are sometimes very important for fabricated devices. 36,37 In Refs. 5 and 6, we have shown that the influence of the radiative mechanism on carrier lifetime in HgCdTe ternary alloys can be omitted.…”

Structural and electrical characterizations of InxGa1-xAs/InP structures for infrared photodetector applications

“…However, the lattice matched substrates with MCT as ZnCdTe are more expensive than III-V substrates and also the growing of MCT structures with low dislocation density on Si or GaAs as alternate substrates have some difficulties. 23 InGaAs along with HgCdTe (MCT) has also been extensively studied with a great potential for the infrared detector applications [24][25][26][27][28][29][30][31][32] such as metal-semiconductor-metal (MSM) photodetectors. [33][34][35] InGaAs detector performance agrees with that of MCT in the 1.5-3.7 lm wavelength range due to similar semiconductor band structures.…”

Temperature-sensitive junction transformations for mid-wavelength HgCdTe photovoltaic infrared detector arrays by laser beam induced current microscope

“…HgCdTe-based photodiodes are widely used in the fabrication of various infrared detectors for military and civil purposes. [1][2][3][4][5][6][7][8][9] They have the advantages of high sensitivity, tunable cutoff wavelength, and relatively wide operating temperature range. However, the performance of HgCdTebased infrared focal plane arrays (IRFPAs) is still strongly affected by different material defects and a complex doping mechanism in the manufacturing process.…”