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Barrier infrared detectors

Martyniuk P., Kopytko M., Rogalski A.

Opto-Electronics Review

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2014

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Vol. 22, No. 2

127-146

EN

In 1959, Lawson and co-workers publication triggered development of variable band gap Hg1-xCdxTe (HgCdTe) alloys providing an unprecedented degree of freedom in infrared detector design. Over the five decades, this material system has successfully fought off major challenges from different material systems, but despite that it has more competitors today than ever before. It is interesting however, that none of these competitors can compete in terms of fundamental properties. They may promise to be more manufacturable, but never to provide higher performance or, with the exception of thermal detectors, to operate at higher temperatures. In the last two decades a several new concepts of photodetectors to improve their performance have been proposed including trapping detectors, barrier detectors, unipolar barrier photodiodes, and multistage detectors. This paper describes the present status of infrared barrier detectors. It is especially addressed to the group of III-V compounds including type-II superlattice materials, although HgCdTe barrier detectors are also included. It seems to be clear that certain of these solutions have merged as a real competitions of HgCdTe photodetectors.

2

HOT infrared photodetectors

Martyniuk P., Rogalski A.

Opto-Electronics Review

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2013

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Vol. 21, No. 2

239-257

EN

At present, uncooled thermal detector focal plane arrays are successfully used in staring thermal imagers. However, the performance of thermal detectors is modest, they suffer from slow response and they are not very useful in applications requiring multispectral detection. Infrared (IR) photon detectors are typically operated at cryogenic temperatures to decrease the noise of the detector arising from various mechanisms associated with the narrow band gap. There are considerable efforts to decrease system cost, size, weight, and power consumption to increase the operating temperature in so-called high-operating-temperature (HOT) detectors. Initial efforts were concentrated on photoconductors and photoelectromagnetic detectors. Next, several ways to achieve HOT detector operation have been elaborated including non-equilibrium detector design with Auger suppression and optical immersion. Recently, a new strategies used to achieve HOT detectors include barrier structures such as nBn, material improvement to lower generation-recombination leakage mechanisms, alternate materials such as superlattices and cascade infrared devices. Another method to reduce detector's dark current is reducing volume of detector material via a concept of photon trapping detector. In this paper, a number of concepts to improve performance of photon detectors operating at near room temperature are presented. Mostly three types of detector materials are considered - HgCdTe and InAsSb ternary alloys, and type-II InAs/GaSb superlattice. Recently, advanced heterojunction photovoltaic detectors have been developed. Novel HOT detector designs, so called interband cascade infrared detectors, have emerged as competitors of HgCdTe photodetectors.

3

High-operating temperature MWIR nBn HgCdTe detector grown by MOCVD

Kopytko M., Kębłowski A., Gawron W., Madejczyk P., Kowalewski A, Jóźwikowski K

Opto-Electronics Review

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2013

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Vol. 21, No. 4

402-405

EN

The paper reports on the first experimental results of the mid-wave infrared (MWIR) HgCdTe barrier detectors operated at near-room temperatures and fabricated using metal organic chemical vapor deposition (MOCVD). SIMS profiles let to compare projected and obtained structures and reveals interdiffusion processes between the layers. Undesirable iodine diffusion from cap to the barrier increase the valance band offset and is the key item in limiting the performance of HgCdTe nBn detector. However, MOCVD technology with a wide range of composition and donor/acceptor doping and without post grown annealing might be successfully adopted for barrier device architectures.

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Niechłodzone i minimalnie chłodzone detektory średniej i dalekiej podczerwieni nowej generacji

Piotrowski A., Gawron W., Kłos K., Rutkowski J., Orman Z. Z., Pawluczyk J., Stanaszek D., Mucha H., Piotrowski J., Rogalski A.

Elektronika : konstrukcje, technologie, zastosowania

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2008

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Vol. 49, nr 11

112-121

PL

Artykuł przedstawia wyniki prac badawczych uzyskanych w Vigo System S.A. i Instytucie Fizyki Technicznej Wojskowej Akademii Technicznej w ramach realizacji zadania nr 5.1 PBZ-MiN-009/T11/2003 pt.: Opracowanie i wykonanie niechłodzonych i minimalnie chłodzonych detektorów średniej i dalekiej podczerwieni nowej generacji. W ramach tej pracy opracowano technologie i przebadano właściwości dwu klas detektorów: detektorów do spektroskopii Fouriera zakresu 3...16 mm i detektorów do szerokopasmowej (1 Gb/s) łączności optycznej w otwartej przestrzeni.

EN

This article presents scientific results of works carried out in VIGO System S.A. and Institute of Applied Physics Military University of Technology, accomplished during realization of grant 5.1 PBZ-MiN-009/T11 /2003 supported by the Polish Ministry of Science and Higher Education and entitled Elaboration and realization of new generation near room temperature middle- and long-wavelength infrared detectors. The paper describes the technology and properties of two types of detectors: photodetectors for Fourier spectroscopy and photodetectors for wide band optical space communication.