A Uncooled α-Si Infrared Detector Using Polyimide as Thermal Isolation Layer

a new structure of the uncooled amorphous silicon (α-Si) infrared detector has been fabricated and characterized. The structure with thermal isolation and infrared absorption based on polyimide (PI) and bottom metal reflective layer is put forward. The fabrication process of the IR detectors is described. The temperature coefficient of resistance (TCR) of α-Si resistance has been investigated. The measurements show that the TCR is up to -2.8%. The detectivity of 1.7×108 cmHz1/2W-1 is achieved with chopping frequency of 30Hz at a bias voltage of 5V. Measurement results indicate that the polyimide layer exhibits excellent thermal isolating characteristics and the unique sandwich IR absorption structure is beneficial to the enhancement of detectivity. Compared with other techniques, the IR detectors using PI as thermal isolation layer are not only with simpler process, lower cost and higher yield, but also suitable for the application of large-scale uncooled infrared focal plane arrays (IRFPA).

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InAsSb-Based Infrared Photodetectors: Thirty Years Later On

Sensors ◽

10.3390/s20247047 ◽

2020 ◽

Vol 20 (24) ◽

pp. 7047

Author(s):

Antoni Rogalski ◽

Piotr Martyniuk ◽

Malgorzata Kopytko ◽

Pawel Madejczyk ◽

Sanjay Krishna

Keyword(s):

Focal Plane ◽

Infrared Detectors ◽

Lower Cost ◽

Review Paper ◽

Infrared Detector ◽

Focal Plane Arrays ◽

Large Area ◽

Technological Advances ◽

New Ideas ◽

Growth Methods

In 1989, one author of this paper (A.R.) published the very first review paper on InAsSb infrared detectors. During the last thirty years, many scientific breakthroughs and technological advances for InAsSb-based photodetectors have been made. Progress in advanced epitaxial methods contributed considerably to the InAsSb improvement. Current efforts are directed towards the photodetector’s cut-off wavelength extension beyond lattice-available and lattice-strained binary substrates. It is suspected that further improvement of metamorphic buffers for epitaxial layers will lead to lower-cost InAsSb-based focal plane arrays on large-area alternative substrates like GaAs and silicon. Most photodetector reports in the last decade are devoted to the heterostructure and barrier architectures operating in high operating temperature conditions. In the paper, at first InAsSb growth methods are briefly described. Next, the fundamental material properties are reviewed, stressing electrical and optical aspects limiting the photodetector performance. The last part of the paper highlights new ideas in design of InAsSb-based bulk and superlattice infrared detectors and focal plane arrays. Their performance is compared with the state-of-the-art infrared detector technologies.

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Anomalous temperature coefficient of resistance in graphene nanowalls/polymer films and applications in infrared photodetectors

Nanophotonics ◽

10.1515/nanoph-2017-0135 ◽

2018 ◽

Vol 7 (5) ◽

pp. 883-892 ◽

Cited By ~ 7

Author(s):

Hui Zhang ◽

Kangyi Zhao ◽

Songya Cui ◽

Jun Yang ◽

Dahua Zhou ◽

...

Keyword(s):

Temperature Coefficient ◽

Coefficient Of Thermal Expansion ◽

Ir Absorption ◽

Temperature Coefficient Of Resistance ◽

Ir Detector ◽

Ir Detectors ◽

Anomalous Temperature ◽

Ir Radiation ◽

Ir Photodetectors ◽

Ir Detection

AbstractGraphene nanowalls (GNWs) exhibit outstanding optoelectronic properties due to their peculiar structure, which makes them a great potential in infrared (IR) detection. Herein, a novel IR detector that is composed of polydimethylsiloxane (PDMS) and designed based on GNWs is demonstrated. Such detector possesses an anomalous temperature coefficient of resistance of 180% K−1 and a relatively high change rate of current (up to 16%) under IR radiation from the human body. It primarily attributes to the ultra-high IR absorption of the GNWs and large coefficient of thermal expansion of PDMS. In addition, the GNW/PDMS device possesses excellent detection performance in the IR region with a responsivity of ~1.15 mA W−1. The calculated detectivity can reach 1.07×108 cm Hz1/2 W−1, which is one or two orders of magnitude larger than that of the traditional carbon-based IR detectors. The significant performance indicates that the GNW/PDMS-based devices reveal a novel design concept and promising applications for the future new-generation IR photodetectors.

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Inverse Infiltration Modeling of Dike Covers Made of Dredged Material Using PEST and AMALGAM

Geosciences ◽

10.3390/geosciences11020041 ◽

2021 ◽

Vol 11 (2) ◽

pp. 41

Author(s):

Tim Jurisch ◽

Stefan Cantré ◽

Fokke Saathoff

Keyword(s):

Large Scale ◽

Measurement Data ◽

Fine Grained ◽

Dredged Materials ◽

Measurement Results ◽

Large Scale Field ◽

Eigenvalue Ratio ◽

Ill Posed ◽

Materials Used ◽

Installation Technology

A variety of studies recently proved the applicability of different dried, fine-grained dredged materials as replacement material for erosion-resistant sea dike covers. In Rostock, Germany, a large-scale field experiment was conducted, in which different dredged materials were tested with regard to installation technology, stability, turf development, infiltration, and erosion resistance. The infiltration experiments to study the development of a seepage line in the dike body showed unexpected measurement results. Due to the high complexity of the problem, standard geo-hydraulic models proved to be unable to analyze these results. Therefore, different methods of inverse infiltration modeling were applied, such as the parameter estimation tool (PEST) and the AMALGAM algorithm. In the paper, the two approaches are compared and discussed. A sensitivity analysis proved the presumption of a non-linear model behavior for the infiltration problem and the Eigenvalue ratio indicates that the dike infiltration is an ill-posed problem. Although this complicates the inverse modeling (e.g., termination in local minima), parameter sets close to an optimum were found with both the PEST and the AMALGAM algorithms. Together with the field measurement data, this information supports the rating of the effective material properties of the applied dredged materials used as dike cover material.

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A uncooled α-Si infrared detector with novel thermal isolation method

2009 4th IEEE International Conference on Nano/Micro Engineered and Molecular Systems ◽

10.1109/nems.2009.5068671 ◽

2009 ◽

Author(s):

Huajun Fang ◽

Xingming Liu ◽

Litian Liu

Keyword(s):

Infrared Detector ◽

Isolation Method ◽

Thermal Isolation

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Optbayesexpt: Sequential Bayesian Experiment Design for Adaptive Measurements

Journal of Research of the National Institute of Standards and Technology ◽

10.6028/jres.126.002 ◽

2021 ◽

Vol 126 ◽

Author(s):

Robert D. McMichael ◽

Sean M. Blakley ◽

Sergey Dushenko

Keyword(s):

Lower Cost ◽

Adaptive Algorithms ◽

Efficient Estimation ◽

Function Parameter ◽

Model Function ◽

Measurement Results ◽

Adaptive Measurements ◽

Order Of Magnitude ◽

Magnitude Increase ◽

Python Package

Optbayesexpt is a public domain, open-source python package that provides adaptive algorithms for efficient estimation/measurement of parameters in a model function. Parameter estimation is the type of measurement one would conventionally tackle with a sequence of data acquisition steps followed by fitting. The software is designed to provide data-based control of experiments, effectively learning from incoming measurement results and using that information to select future measurement settings live and online as measurements progress. The settings are chosen to have the best chances of improving the measurement results. With these methods optbayesexpt is designed to increase the efficiency of a sequence of measurements, yielding better results and/or lower cost. In a recent experiment, optbayesexpt yielded an order of magnitude increase in speed for measurement of a few narrow peaks in a broad spectral range.

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Using and Explaining Individual Dosimetry Data

Asia Pacific Journal of Public Health ◽

10.1177/1010539517693082 ◽

2017 ◽

Vol 29 (2_suppl) ◽

pp. 110S-119S ◽

Cited By ~ 11

Author(s):

Makoto Miyazaki

Keyword(s):

Nuclear Power ◽

Large Scale ◽

Measurement Data ◽

Lessons Learned ◽

Individual Dose ◽

Protection Measures ◽

Measurement Results ◽

Individual Dosimetry ◽

Dose Measurements ◽

Self Protection

Measurement of individual radiation dose is crucial for planning protective measures after nuclear accidents. The purpose of this article is to explain the various initiatives taken after the TEPCO Fukushima Daiichi Nuclear Power Plant accident, including the D-shuttle project wherein residents from affected areas wore a personal dosimeter to measure their own external exposure. The experience in Fukushima revealed several issues such as gaining residents’ trust and ensuring appropriate communication of the measured data. The D-shuttle project also revealed that obtaining individual dose measurement data had 2 purposes, as the information obtained was to be utilized by the residents for self-protection and by the authorities for deriving the dose distribution of the population to aid in designing large-scale protection measures. The lessons learned are that both the residents and the authorities need to understand and share the meaning of individual dose measurements and the measurement results must be used with due respect for the residents’ privacy and other concerns.

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An Architectural and Evaluative Review of Implicit and Explicit SIP Overload Handling

International Journal on Measurement Technologies and Instrumentation Engineering ◽

10.4018/ijmtie.2011100102 ◽

2011 ◽

Vol 1 (4) ◽

pp. 12-27 ◽

Cited By ~ 1

Author(s):

Marco Happenhofer ◽

Joachim Fabini ◽

Christoph Egger ◽

Michael Hirschbichler

Keyword(s):

High Risk ◽

Large Scale ◽

Internet Protocol ◽

Session Initiation Protocol ◽

High Availability ◽

Overload Control ◽

Overload Protection ◽

System Collapse ◽

Measurement Results ◽

Implicit And Explicit

Last year’s trend to migrate circuit-switched voice networks to packet switched Internet Protocol (IP) based networks has favored wide deployment of Session Initiation Protocol (SIP) based systems and networks. As a reaction to large-scale SIP deployment experiences in the field and the need to implement high availability and reliability within these new networks, the focus of SIP extension standardization has shifted from adding new SIP signaling functionality to operational and maintenance aspects, a particular importance being attributed to overload control. Overload denotes a situation in which the traffic injected into a system exceeds the system’s designed capacity. The authors present a detailed categorization of overload architectures and outline main reasons why SIP-based networks are at high risk to collapse when operating at overload. Using measurements in a real SIP infrastructure this paper compares the performance of two overload protection schemes, namely implicit and explicit overload protection, against the performance of non-protected systems. The measurement results recommend overload protection as a mandatory component of commercial SIP deployments to safeguard operation and prevent system collapse in case of overload.

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Surface Preparation and Treatment for Large-Scale 3D-Printed Composite Tooling Coating Adhesion

Coatings ◽

10.3390/coatings8120457 ◽

2018 ◽

Vol 8 (12) ◽

pp. 457 ◽

Cited By ~ 3

Author(s):

Philipp Sauerbier ◽

James Anderson ◽

Douglas Gardner

Keyword(s):

Additive Manufacturing ◽

Large Scale ◽

Lower Cost ◽

Numerical Control ◽

Fused Deposition Modelling ◽

Filler Materials ◽

Coating Adhesion ◽

Fused Deposition ◽

Composite Tooling ◽

3D Printed

Recent advances in large-scale thermoplastic additive manufacturing (AM), using fused deposition modelling (FDM), have shown that the technology can effectively produce large aerospace tools with common feed stocks, costing 2.3 $/kg, such as a 20% carbon-filled acrylonitrile butadiene styrene (ABS). Large-scale additive manufacturing machines have build-volumes in the range of cubic meters and use commercially available pellet feedstock thermoplastics, which are significantly cheaper (5–10 $/kg) than the filament feedstocks for desktop 3D printers (20–50 $/kg). Additionally, large-scale AM machines have a higher material throughput on the order of 50 kg/h. This enables the cost-efficient tool production for several industries. Large-scale 3D-printed tooling will be computerized numerical control (CNC)-machined and -coated, to provide a surface suitable for demolding the composite parts. This paper outlines research undertaken to review and improve the adhesion of the coating systems to large, low-cost AM composite tooling, for marine or infrastructure composite applications. Lower cost tooling systems typically have a lower dimensional accuracy and thermal operating requirements than might be required for aerospace tooling. As such, they can use lower cost commodity grade thermoplastics. The polymer systems explored in the study included polypropylene (PP), styrene-maleic anhydride (SMA), and polylactic acid (PLA). Bio-based filler materials were used to reduce cost and increase the strength and stiffness of the material. Fillers used in the study included wood flour, at 30% by weight and spray-dried cellulose nano-fibrils, at 20% by weight. Applicable adhesion of the coating was achieved with PP, after surface treatment, and untreated SMA and PLA showed desirable coating adhesion results. PLA wood-filled composites offered the best properties for the desired application and, furthermore, they have environment-friendly advantages.

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