Delta Doping in HgCdTe-Based Unipolar Barrier Photodetectors

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Abstract

A method is described whereby the valence band (VB) discontinuity that is present in mercury cadmium telluride (HgCdTe)-based alloy-barrier nBn detectors can be minimized. It is numerically demonstrated that compositionally graded layers can provide the required transition between the wide bandgap CdTe barrier layer and the lattice-matched HgCdTe absorber and contact layers, although a large VB discontinuity is present. In addition, the incorporation of delta-doped (δ -doped) layers in the vicinity of the barrier region can minimize the VB discontinuity, thus blocking the flow of majority carriers and allowing unimpeded flow of photogenerated minority carriers. This strategy results in diffusion-limited dark current at low reverse bias combined with efficient collection of photogenerated carriers. The nBn structure proposed in this paper can be applied to other semiconductor materials operating in various infrared wavelength bands. The method is not limited to the nBn structure and can be applied to any xBx barrier detector structure (with x = n, p) configuration in order to minimize the energy band discontinuity in the corresponding minority carrier band.

Original languageEnglish
Article number8435934
Pages (from-to)4340-4345
JournalIEEE Transactions on Electron Devices
Volume65
Issue number10
DOIs
Publication statusPublished - Oct 2018

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Photodetectors
Valence bands
Doping (additives)
Detectors
Cadmium telluride
Mercury (metal)
Dark currents
Electron transitions
Band structure
Energy gap
Semiconductor materials
Infrared radiation
Wavelength

Cite this

@article{d835e049fee9437bb6eec776c208b19e,
title = "Delta Doping in HgCdTe-Based Unipolar Barrier Photodetectors",
abstract = "A method is described whereby the valence band (VB) discontinuity that is present in mercury cadmium telluride (HgCdTe)-based alloy-barrier nBn detectors can be minimized. It is numerically demonstrated that compositionally graded layers can provide the required transition between the wide bandgap CdTe barrier layer and the lattice-matched HgCdTe absorber and contact layers, although a large VB discontinuity is present. In addition, the incorporation of delta-doped (δ -doped) layers in the vicinity of the barrier region can minimize the VB discontinuity, thus blocking the flow of majority carriers and allowing unimpeded flow of photogenerated minority carriers. This strategy results in diffusion-limited dark current at low reverse bias combined with efficient collection of photogenerated carriers. The nBn structure proposed in this paper can be applied to other semiconductor materials operating in various infrared wavelength bands. The method is not limited to the nBn structure and can be applied to any xBx barrier detector structure (with x = n, p) configuration in order to minimize the energy band discontinuity in the corresponding minority carrier band.",
keywords = "δ -doping, Cadmium compounds, Detectors, Doping, doping modulation, II-VI semiconductor materials, infrared (IR) detector, mercury cadmium telluride (HgCdTe), nBn, Photodetectors, Photonic band gap, Semiconductor process modeling, unipolar barrier, valence band (VB) discontinuity",
author = "Akhavan, {Nima Dehdashti} and Umana-Membreno, {Gilberto Armando} and Renjie Gu and Jarek Antoszewski and Lorenzo Faraone and Harris Fellow",
year = "2018",
month = "10",
doi = "10.1109/TED.2018.2861378",
language = "English",
volume = "65",
pages = "4340--4345",
journal = "IEEE Transactions on Electron Devices",
issn = "0018-9383",
publisher = "IEEE, Institute of Electrical and Electronics Engineers",
number = "10",

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TY - JOUR

T1 - Delta Doping in HgCdTe-Based Unipolar Barrier Photodetectors

AU - Akhavan, Nima Dehdashti

AU - Umana-Membreno, Gilberto Armando

AU - Gu, Renjie

AU - Antoszewski, Jarek

AU - Faraone, Lorenzo

AU - Fellow, Harris

PY - 2018/10

Y1 - 2018/10

N2 - A method is described whereby the valence band (VB) discontinuity that is present in mercury cadmium telluride (HgCdTe)-based alloy-barrier nBn detectors can be minimized. It is numerically demonstrated that compositionally graded layers can provide the required transition between the wide bandgap CdTe barrier layer and the lattice-matched HgCdTe absorber and contact layers, although a large VB discontinuity is present. In addition, the incorporation of delta-doped (δ -doped) layers in the vicinity of the barrier region can minimize the VB discontinuity, thus blocking the flow of majority carriers and allowing unimpeded flow of photogenerated minority carriers. This strategy results in diffusion-limited dark current at low reverse bias combined with efficient collection of photogenerated carriers. The nBn structure proposed in this paper can be applied to other semiconductor materials operating in various infrared wavelength bands. The method is not limited to the nBn structure and can be applied to any xBx barrier detector structure (with x = n, p) configuration in order to minimize the energy band discontinuity in the corresponding minority carrier band.

AB - A method is described whereby the valence band (VB) discontinuity that is present in mercury cadmium telluride (HgCdTe)-based alloy-barrier nBn detectors can be minimized. It is numerically demonstrated that compositionally graded layers can provide the required transition between the wide bandgap CdTe barrier layer and the lattice-matched HgCdTe absorber and contact layers, although a large VB discontinuity is present. In addition, the incorporation of delta-doped (δ -doped) layers in the vicinity of the barrier region can minimize the VB discontinuity, thus blocking the flow of majority carriers and allowing unimpeded flow of photogenerated minority carriers. This strategy results in diffusion-limited dark current at low reverse bias combined with efficient collection of photogenerated carriers. The nBn structure proposed in this paper can be applied to other semiconductor materials operating in various infrared wavelength bands. The method is not limited to the nBn structure and can be applied to any xBx barrier detector structure (with x = n, p) configuration in order to minimize the energy band discontinuity in the corresponding minority carrier band.

KW - δ -doping

KW - Cadmium compounds

KW - Detectors

KW - Doping

KW - doping modulation

KW - II-VI semiconductor materials

KW - infrared (IR) detector

KW - mercury cadmium telluride (HgCdTe)

KW - nBn

KW - Photodetectors

KW - Photonic band gap

KW - Semiconductor process modeling

KW - unipolar barrier

KW - valence band (VB) discontinuity

UR - http://www.scopus.com/inward/record.url?scp=85051626313&partnerID=8YFLogxK

U2 - 10.1109/TED.2018.2861378

DO - 10.1109/TED.2018.2861378

M3 - Article

VL - 65

SP - 4340

EP - 4345

JO - IEEE Transactions on Electron Devices

JF - IEEE Transactions on Electron Devices

SN - 0018-9383

IS - 10

M1 - 8435934

ER -