Wyniki wyszukiwania - Biblioteka Nauki

1

Understanding the NEΔT of tactical infrared focal plane arrays

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Norton P.

Opto-Electronics Review

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2012

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tom Vol. 20, No. 3

275-278

EN

NEΔT is the commonly used figure-of-merit for infrared-imaging systems using focal plane arrays (FPAs). This paper discusses an intuitive approach to understanding what determines this value in the majority of MWIR and LWIR broad-band applications, namely, the available charge storage capacity of the FPA readout. This conclusion is a consequence of the negligible amount of dark current compared to photo-current for modern detector technology.

2

Theoretical modelling of XBn T2SLs InAs/InAsSb/B-AlAsSb mid-wave detector operating below thermoelectrical cooling

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Martyniuk P. , Michalczewski K. , Tsai T. Y. , Wu C. H. , Wu Y. R.

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2019

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tom Vol. 27, No. 3

275--281

EN

The paper reports on the barrier mid-wave infrared InAs/InAsSb (xSb = 0.4) type-II superlattice detector operating below thermoelectrical cooling. AlAsSb with Sb composition, xSb = 0.97; barrier doping, ND < 2×10¹⁶ cm⁻³ leading to valence band offset below 100 meV in relation to the active layer doping, ND = 5×10¹⁵ cm⁻³ was proved to be proper material not introducing extra barrier in valence band in the analyzed temperature range in XBn architectures. The detectivity of the simulated structure was assessed at the level of ∼ 1011 Jones at T ∼ 100K assuming absorber thickness, d = 3 μm. The detector’s architecture for high frequency response operation, τs = 420 ps (T ∼ 77K) was presented with a reduced active layer of d = 1 μm.

3

Fast Response Hot (111) HGCDTE MWIR Detectors

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Grodecki K. , Martyniuk P. , Kopytko M. , Kowalewski A. , Stępień D. , Kębłowski A. , Piotrowski A. , Piotrowski J. , Gawron W. , Rogalski A.

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tom Vol. 24, nr 3

509--514

EN

In this work we report simulation and experimental results for an MWIR HgCdTe photodetector designed by computer simulation and fabricated in a joint laboratory run by VIGO Sytems S.A. and Military University of Technology. The device is based on a modified N+pP+ heterostructure grown on 2”., epiready, semi-insulating (100) GaAs substrates in a horizontal MOCVD AIX 200 reactor. The devices were examined by measurements of spectral and time responses as a function of a bias voltage and operating temperatures. The time response was measured with an Optical Parametric Oscillator (OPO) as the source of ~25 ps pulses of infrared radiation, tuneable in a 1.55–16 μm spectral range. Two-stage Peltier cooled devices (230 K) with a 4.1 μm cut-off wavelength were characterized by 1.6 × 1012 cm Hz1/2/W peak detectivity and < 1 ns time constant for V > 500 mV.

4

MOCVD grown MWIR HgCdTe detectors for high operation temperature conditions

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Martyniuk P. , Koźniewski A. , Kębłowski A. , Gawron W. , Rogalski A.

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2014

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tom Vol. 22, No. 2

118-126

EN

The paper reports on photoelectrical performance of the mid-wave infrared HgCdTe detector for high operating temperature condition. Detector structure was simulated with APSYS numerical platform by Crosslight Inc. The comprehensive analysis of the detector performance such as dark current, detectivity, time response vs. device architecture and applied bias has been performed. The N⁺pP⁺n⁺ HgCdTe heterostructure photodiode operating in room temperature at a wavelength range of 2.6–3.6 μm enabled to reach: detectivity ~ 8.7×10¹⁰ cmHz¹/²/W, responsivity ~ 1.72 A/W and time response ~ 145 ps(V = 200 mV).

5

Demonstration of HOT photoresponse of MWIR T2SLs InAs/InAsSb photoresistors

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Michalczewski K. , Tsai T. Y. , Martyniuk P. , Wu C. H.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2019

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tom Vol. 67, nr 1

141--145

EN

We report on the photoresponse of mid-wavelength infrared radiation (MWIR) type-II superlattices (T2SLs) InAs/InAsSb high operating temperature (HOT) photoresistor grown on GaAs substrate. The device consists of a 200 periods of active layer grown on GaSb buffer layer. The photoresistor reached a 50% cut-off wavelength of 5 μm and 6 μm at 200 K and 300 K respectively. The time constant of 30 ns is observed at 200 K under 1 V bias. This is the first observation of the photoresponse in MWIR T2SLs InAs/InAsSb above 200 K..

6

Low-noise infrared and visible focal plane arrays

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Kozlowski L. , Vural K. , Luo J. , Tomasini A. , Liu T. , Kleinhans W. E.

Opto-Electronics Review

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1999

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tom Vol. 7, No. 4

259-269

EN

While charge-coupled device ( CCD ) technology is often perceived to provide nearly optimum signal multiplexing and very low imager noise, coupling high performance detectors ( at cutoff wavelengths from 0.6 žmto 17 um ) to CMOS multiplexers provides lower (<10 e-) read noise at high data rates using several pixel amplifier schemes. This superiority is fundamental and has been validated on infrared and visible focal plane arrays. Thus the robust pixel-based signal amplification facilitated by sub-micron CMOS is stimulating low-noise focal plane array (FPA) development for discriminating applications including infrared astronomy, wavefront sensing, spectroscopy, and spaceborne images. Enabled by Moore's Law and concomitant increases in integration density, commercial imagers for consumer video are also providing very low read noise and high sensitivity. Hence we report the ability to usefully detect quanta at non-cryogenic operating temperatures because read noise is at the single-electron level at high video rates. While such advances are typically first demonstrated on infrared sensors, the enhancements migrate to visible devices as soon as the available lithography of the prevailing silicon CMOS technology permits, because visible imager pixels are necessarily much smaller to match the optical blur.

7

Uncooled microbolometer detector: recent developments at ULIS

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Tissot J. L. , Trouilleau C. , Fieque B. , Crastes A. , Legras O.

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tom Vol. 14, No. 1

25-32

EN

Uncooled infrared focal plane arrays are being developed for a wide range of thermal imaging applications. Fire-fighting, predictive maintenance, process control and thermography are a few of the industrial applications which could take benefit from uncooled infrared detector. Therefore, to answer these markets, a 35-µm pixel-pitch uncooled IR detector technology has been developed enabling high performance 160x120 and 384x288 arrays production. Besides a wide-band version from uncooled 320x240/45 µm array has been also developed in order to address process control and more precisely industrial furnaces control. The ULIS amorphous silicon technology is well adapted to manufacture low cost detector in mass production. After some brief microbolometer technological background, we present the characterization of 35 µm pixel-pitch detector as well as the wide-band 320x240 infrared focal plane arrays with a pixel pitch of 45 µm.

8

Type-II InAs/GaSb photodiodes and focal plane arrays aimed at high operating temperatures

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Razeghi M. , Abdollahi Pour S. , Huang E. K. , Chen G. , Haddadi A. , Nguyen B. M.

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tom Vol. 19, No. 3

261-269

EN

Recent efforts to improve the performance of type II InAs/GaSb superlattice photodiodes and focal plane arrays (FPA) have been reviewed. The theoretical bandstructure models have been discussed first. A review of recent developments in growth and characterization techniques is given. The efforts to improve the performance of MWIR photodiodes and focal plane arrays (FPAs) have been reviewed and the latest results have been reported. It is shown that these improvements has resulted in background limited performance (BLIP) of single element photodiodes up to 180 K. FPA shows a constant noise equivalent temperature difference (NEDT) of 11 mK up to 120 K and it shows human body imaging up to 170 K.

9

Investigation of HgCdTe avalanche photodiodes for HOT condition

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Manyk T. , Sobieski J. , Matuszelański K. , Rutkowski J. , Martyniuk P.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2024

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tom Vol. 72, nr 3

art. no. e149173

EN

The performance of long-wave infrared (LWIR) x = 0.22 HgCdTe avalanche photodiodes (APDs) was presented. The dark currentvoltage characteristics at temperatures 200 K, 230 K, and 300 K were measured and numerically simulated. Theoretical modeling was performed by the numerical Apsys platform (Crosslight). The effects of the tunneling currents and impact ionization in HgCdTe APDs were calculated. Dark currents exhibit peculiar features which were observed experimentally. The proper agreement between the theoretical and experimental characteristics allowed the determination that the material parameters of the absorber were reached. The effect of the multiplication layer profile on the detector characteristics was observed but was found to be insignificant.