A5084912340- Thin-Film Transistor Technologies
- Advanced Semiconductor Detectors and Materials
- Silicon and Solar Cell Technologies
- Silicon Nanostructures and Photoluminescence
- Phase-change materials and chalcogenides
- Chalcogenide Semiconductor Thin Films
- Radiation Detection and Scintillator Technologies
- Luminescence Properties of Advanced Materials
- Semiconductor materials and devices
- Fire effects on ecosystems
- CCD and CMOS Imaging Sensors
- X-ray Spectroscopy and Fluorescence Analysis
- Glass properties and applications
- Theoretical and Computational Physics
- Smart Agriculture and AI
- Electronic and Structural Properties of Oxides
- Bryophyte Studies and Records
- Infrared Target Detection Methodologies
- Yeasts and Rust Fungi Studies
- Transition Metal Oxide Nanomaterials
- Electronic Packaging and Soldering Technologies
- Liquid Crystal Research Advancements
- Wood and Agarwood Research
- Digital Radiography and Breast Imaging
- Semiconductor Quantum Structures and Devices
Universität Hamburg
2024
University of Saskatchewan
2011-2024
Queen's University
2022
Roscommon University Hospital
2005-2006
Annual Reviews
2006
University of Chicago
1984-1992
Forest and Wood Products (Australia)
1969
Commonwealth Scientific and Industrial Research Organisation
1969
We consider the charge collection efficiency (CCE) for semiconductors in which transport parameters, drift mobility μ, and carrier lifetime τ have spatial dependence, i.e., μ = μ(x) τ(x), where x is distance from radiation receiving top electrode toward rear electrode. The small signal packet analysis (CPDA) re-examined, CCE electrons holes formulated terms of μ(x)τ(x)F(x), F field. use two model variations that are linear exponential then calculate compare determined CPDA equation,...
This work presents the excess noise and thermoelectric (Seebeck) measurements on polycrystalline vanadium dioxide (VO2) thin films. Noise spectral power density (SPD) of current fluctuations in semiconducting (SC) phase had a typical flicker (f−γ) characteristic with an average slope parameter γ 1.13. Normalized SPD (Sn) values obtained SC-phase indicate that originates bulk film. On contrary, metallic (M)-phase, were greater than unity, observed Sn indicated origin is most likely from...
Stabilized amorphous selenium (a-Se) is one of the x-ray photoconductors that currently used in recently developed direct conversion flat panel image detectors. We have studied recombination free holes with trapped electrons stabilized a-Se. Electrons were deeply a-Se by carrying out repetitive electron time-of-flight (TOF) transient photoconductivity experiments. By using conventional and interrupted field hole (IFTOF) techniques a TOF, IFTOF, TOF sequence, we able to develop technique...
The authors have examined the relaxation of electrical properties vacuum-deposited x-ray photoconductor-type a-Se1−xAsx (x=0%–0.5%) films in terms time evaluation deep trapping τ, i.e., carrier lifetime, and drift mobility μ from samples were brought to 23 °C after they had been annealed at 55 (above glass-transition temperature Tg) for 30 min. changes lifetime arise structural-relaxation processes modeled using a stretched exponential-relaxation process, τ=τ∞+(τo−τ∞)exp[−(t/τsr)β], where τ∞...
Stabilized amorphous selenium (a-Se) photoconductive layers are currently used in the majority of modern digital x-ray flat panel imaging detectors mammography. We examine effects pre-exposure a-Se to high-dose irradiation on both hole and electron lifetimes, τe τh, respectively, without any field applied device. The was from an Al-filtered tungsten target tube. show that reduction τh depends only total or accumulated dose, D, absorbed a-Se, not rate dose delivery, dD/dt, over range 0.15...
Crop detection is integral for precision agriculture applications such as automated yield estimation or fruit picking. However, crop detection, e.g., apple in orchard environments remains challenging due to a lack of large-scale datasets and the small relative size crops image. In this work, we address these challenges by reformulating task semi-supervised manner. To end, provide large, high-resolution dataset MAD <sup xmlns:mml="http://www.w3.org/1998/Math/MathML"...
Hecht collection efficiency η0 and its formulations for exponential absorption have been widely used in modeling charge photoconductive detectors. The basic assumption of the formulation is that electric field device uniform, i.e., photoinjected carriers do not perturb field. Here, we Monte Carlo simulations to model initial injection electron hole pairs their subsequent transport trapping presence an field, which calculated from Poisson equation. Each injected carrier tracked as it moves...
Abstract We have measured conductance fluctuations in n-type hydrogenated amorphous silicon using current densities J the range 0·1 < 0·55 A cm−2 at various temperatures from 13°C to 170°C. The noise power density varies as 1/f 2 Hz 5 kHz and increases square of bias all studied expected for flicker noise. magnitude with temperature and, if assumed follow an Arrhenius curve, has activation energy eV. For exceeding about 1 cm −2, we find large abrupt changes superimposed on reminiscent random...
Published work on conductance fluctuations in hydrogenated amorphous silicon is surveyed. There are many reports of 1/f noise, some describing unusual features such as non-Gaussian statistics. The relative insensitivity to doping and temperature highlighted. In addition the random-telegraph-like noise often reported. successes failures generation–recombination models for current filament telegraph summarised.
The authors calculate the variance in output of an integrating sensor or detector when presence 1/fα noise input sensor. calculations are based on mapping onto a linear, time-invariant filter; approach is general and can be used for any that so mapped. Formulae signal-to-noise ratio given simple with three different methods background subtraction, including double sampling, has two integrations, triple sampling where average integrations before after signal subtracted from integration during...
In the present paper, we have investigated hole transport in stabilized a‐Se films using interrupted‐field‐time‐of‐flight (IFTOF) experiments with interruption times up to 600 μs. A distinct advantage of IFTOF measurements is that one can monitor average “free” concentration p ( t ) (= x , averaged over thickness sample L at a given location 1 inasmuch as applied field removed certain time for an period i . At + reapplied and recovered photocurrent 2 = measured respect original The...
Electron transport in vacuum-deposited a-Se films with thicknesses varying from 13 to 501 μm has been investigated by conventional time-of-flight (TOF) and interrupted field TOF experiments. To separate the influences of electric thickness, all experiments were performed at a constant field. It found that electron mobility is relatively thick (L > 50 μm) increases thinner < decreasing thickness. On other hand, lifetime thickness independent L μm, but drops sharply thin when μm. These...