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C Weaverdyck - One of the best experts on this subject based on the ideXlab platform.
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measurement of reciprocity failure in near Infrared Detectors
Publications of the Astronomical Society of the Pacific, 2011Co-Authors: T Biesiadzinski, Michael Schubnell, Wolfgang Lorenzon, Robert Newman, G Tarle, C WeaverdyckAbstract:ABSTRACT. Flux-dependent nonlinearity (reciprocity failure) in HgCdTe near-Infrared Detectors can severely impact an instrument’s performance, in particular, with respect to precision photometric measurements. The cause of this effect is presently not understood. To investigate reciprocity failure, a dedicated test system was built. For flux levels between 1 and 50,000 photons s-1 50 , 000 photons s - 1 , a sensitivity to reciprocity failure of approximately 0.1% decade-1 0.1 % decade - 1 was achieved. A wavelength-independent nonlinearity due to reciprocity failure of about 0.35% decade-1 0.35 % decade - 1 was measured in a 1.7 μm HgCdTe detector.
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measurement of reciprocity failure in near Infrared Detectors
arXiv: Instrumentation and Methods for Astrophysics, 2010Co-Authors: T Biesiadzinski, Michael Schubnell, Wolfgang Lorenzon, Robert Newman, G Tarle, C WeaverdyckAbstract:Flux dependent non-linearity (reciprocity failure) in HgCdTe near Infrared Detectors can severely impact an instrument's performance, in particular with respect to precision photometric measurements. The cause of this effect is presently not understood. To investigate reciprocity failure, a dedicated test system was built. For flux levels between 1 and 50,000 photons/s, a sensitivity to reciprocity failure of approximately 0.1%/decade was achieved. A wavelength independent non-linearity due to reciprocity failure of about 0.35%/decade was measured in a 1.7 micron HgCdTe detector.
Yasuhiko Arakawa - One of the best experts on this subject based on the ideXlab platform.
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Tight binding analysis for quantum-wire lasers and quantum-wire Infrared Detectors
IEEE Journal of Quantum Electronics, 1991Co-Authors: T. Yamauchi, T. Takahashi, Yasuhiko ArakawaAbstract:The tight binding method is applied to the analysis of the energy band structure of GaAs-AlGaAs quantum-wire lasers and Infrared Detectors. The authors clarify the differences between the device characteristics based on the conventional Kronig-Penney model and those based on the tight binding method. The results show the importance of considering the band structure carefully when predicting the device characteristics. The tight binding method for the quantum wire is described. The gain and the differential gain characteristics, which are important parameters for the lasing characteristics are discussed using the band structures calculated by the tight binding method. The absorption spectral properties of the quantum-wire Infrared detector are discussed. >
T Biesiadzinski - One of the best experts on this subject based on the ideXlab platform.
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measurement of reciprocity failure in near Infrared Detectors
Publications of the Astronomical Society of the Pacific, 2011Co-Authors: T Biesiadzinski, Michael Schubnell, Wolfgang Lorenzon, Robert Newman, G Tarle, C WeaverdyckAbstract:ABSTRACT. Flux-dependent nonlinearity (reciprocity failure) in HgCdTe near-Infrared Detectors can severely impact an instrument’s performance, in particular, with respect to precision photometric measurements. The cause of this effect is presently not understood. To investigate reciprocity failure, a dedicated test system was built. For flux levels between 1 and 50,000 photons s-1 50 , 000 photons s - 1 , a sensitivity to reciprocity failure of approximately 0.1% decade-1 0.1 % decade - 1 was achieved. A wavelength-independent nonlinearity due to reciprocity failure of about 0.35% decade-1 0.35 % decade - 1 was measured in a 1.7 μm HgCdTe detector.
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measurement of reciprocity failure in near Infrared Detectors
arXiv: Instrumentation and Methods for Astrophysics, 2010Co-Authors: T Biesiadzinski, Michael Schubnell, Wolfgang Lorenzon, Robert Newman, G Tarle, C WeaverdyckAbstract:Flux dependent non-linearity (reciprocity failure) in HgCdTe near Infrared Detectors can severely impact an instrument's performance, in particular with respect to precision photometric measurements. The cause of this effect is presently not understood. To investigate reciprocity failure, a dedicated test system was built. For flux levels between 1 and 50,000 photons/s, a sensitivity to reciprocity failure of approximately 0.1%/decade was achieved. A wavelength independent non-linearity due to reciprocity failure of about 0.35%/decade was measured in a 1.7 micron HgCdTe detector.
M Kopytko - One of the best experts on this subject based on the ideXlab platform.
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Status of HgCdTe Barrier Infrared Detectors Grown by MOCVD in Military University of Technology
Journal of Electronic Materials, 2016Co-Authors: M Kopytko, W. Gawron, P. Martyniuk, K. Jóźwikowski, P. Madejczyk, A. Kowalewski, O. Markowska, A. Rogalski, J. RutkowskiAbstract:In this paper we present the status of HgCdTe barrier Detectors with an emphasis on technological progress in metalorganic chemical vapor deposition (MOCVD) growth achieved recently at the Institute of Applied Physics, Military University of Technology. It is shown that MOCVD technology is an excellent tool for HgCdTe barrier architecture growth with a wide range of composition, donor / acceptor doping, and without post-grown annealing. The device concept of a specific barrier bandgap architecture integrated with Auger-suppression is as a good solution for high-operating temperature Infrared Detectors. Analyzed devices show a high performance comparable with the state-of-the-art of HgCdTe photodiodes. Dark current densities are close to the values given by “Rule 07” and detectivities of non-immersed Detectors are close to the value marked for HgCdTe photodiodes. Experimental data of long-wavelength Infrared detector structures were confirmed by numerical simulations obtained by a commercially available software APSYS platform. A detailed analysis applied to explain dark current plots was made, taking into account Shockley–Read–Hall, Auger, and tunneling currents.
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challenges of small pixel Infrared Detectors a review
Reports on Progress in Physics, 2016Co-Authors: Aymeric Rogalski, Piotr Martyniuk, M KopytkoAbstract:In the last two decades, several new concepts for improving the performance of Infrared Detectors have been proposed. These new concepts particularly address the drive towards the so-called high operating temperature focal plane arrays (FPAs), aiming to increase detector operating temperatures, and as a consequence reduce the cost of Infrared systems. In imaging systems with the above megapixel formats, pixel dimension plays a crucial role in determining critical system attributes such as system size, weight and power consumption (SWaP). The advent of smaller pixels has also resulted in the superior spatial and temperature resolution of these systems. Optimum pixel dimensions are limited by diffraction effects from the aperture, and are in turn wavelength-dependent. In this paper, the key challenges in realizing optimum pixel dimensions in FPA design including dark current, pixel hybridization, pixel delineation, and unit cell readout capacity are outlined to achieve a sufficiently adequate modulation transfer function for the ultra-small pitches involved. Both photon and thermal Detectors have been considered. Concerning Infrared photon Detectors, the trade-offs between two types of competing technology-HgCdTe material systems and III-V materials (mainly barrier Detectors)-have been investigated.
Sarath D. Gunapala - One of the best experts on this subject based on the ideXlab platform.
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GaSb grass as a novel antireflective surface for Infrared Detectors
Infrared Technology and Applications XLV, 2019Co-Authors: Brian Pepper, Alexander Soibel, Arezou Khoshakhlagh, Karl Yee, Anita M. Fisher, Sam A. Keo, Sarath D. GunapalaAbstract:GaSb has a high numerical index (approximately 3.90 at a wavelength of 2 μm), leading to reflection of about 35% of incoming photons, depending on wavelength. This results in a significant loss of quantum efficiency for GaSb-based Infrared Detectors when backside-illuminated, since GaSb is the first material encountered. Here we demonstrate a way of etching broadband antireflective GaSb grass using an inductively coupled Cl2 plasma etch with O2 micromasking, and we examine the possibility for using this material as an antireflective surface for Infrared Detectors (a patent is pending concerning integration with GaSb-based Infrared Detectors). We demonstrate sub-10% reflectivity for wavelengths ranging from 200 nm to 12.2 μm and at angles of incidence up to 58°.
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hole effective masses and subband splitting in type ii superlattice Infrared Detectors
Applied Physics Letters, 2016Co-Authors: David Z. Ting, Alexander Soibel, Sarath D. GunapalaAbstract:We explore band structure effects to help determine the suitability of n-type type-II superlattice (T2SL) absorbers for Infrared Detectors. It is often assumed that the exceedingly large growth-direction band-edge curvature hole effective mass in n-type long wavelength Infrared (LWIR) T2SL would lead to low hole mobility and therefore low detector collection quantum efficiency. We computed the thermally averaged conductivity effective mass and show that the LWIR T2SL hole conductivity effective mass along the growth direction can be orders of magnitude smaller than the corresponding band-edge effective mass. LWIR InAs/GaSb T2SL can have significantly smaller growth-direction hole conductivity effective mass than its InAs/InAsSb counterpart. For the InAs/InAsSb T2SL, higher Sb fraction is more favorable for hole transport. Achieving long hole diffusion length becomes progressively more difficult for the InAs/InAsSb T2SL as the cutoff wavelength increases, since its growth-direction hole conductivity effect...
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High performance long-wave type-II superlattice Infrared Detectors
Journal of Vacuum Science & Technology B Nanotechnology and Microelectronics: Materials Processing Measurement and Phenomena, 2013Co-Authors: Arezou Khoshakhlagh, Linda Hoglund, Jean Nguyen, David Z. Ting, Alexander Soibel, Cory J. Hill, Sam A. Keo, Sarath D. GunapalaAbstract:The authors report on growth, material characterization, and device performance of Infrared photoDetectors based on type II InAs/GaSb superlattices using the complementary barrier Infrared detector (CBIRD) design. In this paper, control steps for improvement of material quality in terms of surface, structural, and optical properties of Infrared Detectors grown at Jet Propulsion Laboratory are described. For a specific CBIRD studied, these quality control steps indicate high structural and optical quality of the grown material. Furthermore, single-element detector from the optimized growth conditions exhibit dark current density less than 1 × 10−5 A/cm2 at applied biases up to Vb = 0.36 V (T = 77 K), so this material can be utilized for focal plane arrays development.
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type ii superlattice Infrared Detectors
Semiconductors and Semimetals, 2011Co-Authors: David Z. Ting, Linda Hoglund, Jean Nguyen, Alexander Soibel, Arezou Khoshakhlagh, Cory J. Hill, Sarath D. GunapalaAbstract:Publisher Summary This chapter provides an overview of type-II superlattice Infrared Detectors. The type-II InAs/GaSb superlattices have several fundamental properties that make them suitable for Infrared detection: (1) their band gaps can be made arbitrarily small by design, (2) they are more immune to band-to-band tunneling compared with bulk material, (3) the judicious use of strain in type-II InAs/GaInSb strained layer superlattice (SLS) can enhance its absorption strength over that of the type-II InAs/GaSb superlattice to a level comparable with HgVdTe (MCT), and (4) type-II InAs/Ga(In)Sb superlattices also reduce Auger recombination. In addition, the dark current characteristics of type-II superlattice-based single element long-wavelength Infrared (LWIR) Detectors are currently approaching state-of-the-art MCT detector. Noise measurements highlight the need for surface leakage suppression, which can be tackled by improved etching, passivation, and device design. The chapter also describes the principles behind advanced superlattice Infrared Detectors based on heterostructure designs. It also explores some aspects of device fabrication and characterization.
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Antimonide-based barrier Infrared Detectors
Infrared Technology and Applications XXXVI, 2010Co-Authors: David Z. Ting, Jean Nguyen, Alexander Soibel, Cory J. Hill, Sam A. Keo, Michael C. Lee, Jason M. Mumolo, John K. Liu, Sarath D. GunapalaAbstract:The nearly lattice-matched InAs/GaSb/AlSb (antimonide) material system offers tremendous flexibility in realizing high-performance Infrared Detectors. Antimonide-based alloy and superlattice Infrared absorbers can be customized to have cutoff wavelengths ranging from the short wave Infrared (SWIR) to the very long wave Infrared (VLWIR). They can be used in constructing sophisticated heterostructures to enable advanced Infrared photodetector designs. In particular, they facilitate the construction of unipolar barriers, which can block one carrier type but allow the unimpeded flow of the other. Unipolar barriers are used to implement the barrier infra-red detector (BIRD) design for increasing the collection efficiency of photo-generated carriers, and reducing dark current generation without impeding photocurrent flow. We report our recent efforts in achieving state-of-the-art performance in antimonide alloy and superlattice based Infrared photoDetectors using the BIRD architecture. Specifically, we report a 10 μm cutoff superlattice device based on a complementary barrier Infrared detector (CBIRD) design. The detector, without antireflection coating or passivation, exhibits a responsivity of 1.5 A/W and a dark current density of 1×10-5 A/cm2 at 77K under 0.2 V bias. It reaches 300 K background limited Infrared photodetection (BLIP) operation at 87 K, with a blackbody BLIP D* value of 1.1×1011 cm-Hz1/2/W for f/2 optics under 0.2 V bias.