Related papers: Investigation of charge sharing among electrode st…
We are currently investigating the spatial resolution of highly pixelated Cadmium Zinc Telluride (CZT) detector for imaging applications. A 20 mm {\times} 20 mm {\times} 5 mm CZT substrate was fabricated with 600 {\mu}m pitch pixels (500…
The geometry of electrodes is one of the most important factors in determining the performance of orthogonal-strip detectors. The aim of this work is to study the performance of a 5 mm thick cross-strip CdZnTe detector with different…
We propose a new strip configuration for CdTe X-ray detectors, named "Wide-gap CdTe strip detector", in which the gap between adjacent strips is much wider than the width of each strip. It has been known that the observed energies of an…
When a $\gamma$-ray interacts in a semiconductor detector, the resulting electron-hole charge clouds drift towards their respective electrodes for signal collection. These charge clouds will expand over time due to both thermal diffusion…
The development of CdZnTe detectors with an orthogpnal coplanar anode structure has important implications for future astrophysical instrumentation. As electron-only devices, like pixel detectors, coplanar anode strip detectors can be…
A pixel detector with a CVD diamond sensor has been studied in a 180 GeV/c pion beam. The charge collection properties of the diamond sensor were studied as a function of the track position, which was measured with a silicon microstrip…
We have evaluated the performance of a fine pitch CdTe Double-sided Strip Detector (CdTe-DSD), which was originally developed for the focal plane detector of a hard X-ray telescope to observe the Sun. The detector has a thickness of 750 um…
In an ideal germanium detector, fully-absorbed monoenergetic gamma-rays will appear in the measured spectrum as a narrow peak, broadened into a Gaussian of width determined only by the statistical properties of charge cloud generation and…
Surface charging is a phenomenon ubiquitously observable in in-situ transmission electron microscopy of non-conducting specimens as a result of electron beam/sample interactions or optical stimuli and often limits the achievable image…
We combined steady-state photoconductivity and laser-induced transient current measurements under above-band-gap illumination to study the space charge formation in CdZnTe. Analytical as well as numerical models describing space charge…
The purpose of this project is to investigate the use of charge couple devices (CCDs) to detect electrons directly. This can be done in transmission electron microscopy (TEM) for electrons over 100 KeV, but for space plasma instruments,…
We present an experimental study of electron-electron exchange interaction in self-assembled CdTe/ZnTe quantum dots based on the photoluminescence measurements. The character and strength of this interaction are obtained by simultaneous…
The charge collection properties in different particle sensor materials with respect to the shape of the generated signals, the electric field within the detector, the charge carrier mobility and the carrier lifetime are studied with the…
Measuring the depth of interaction in thick Cadmium-Zinc-Telluride (CZT) detectors allows improved imaging and spectroscopy for hard X-ray imaging above 100 keV. The Energetic X-ray Imaging Survey Telescope (EXIST) will employ relatively…
We studied the effects of bulk and surface conductivity on the performance of high-resistivity CdZnTe (CZT) pixel detectors with Pt contacts. We emphasize the difference in mechanisms of the bulk and surface conductivity as indicated by…
Charge multiplication (CM) in p$^+$n epitaxial silicon pad diodes of 75, 100 and 150 $\upmu$m thickness at high voltages after proton irradiation with 1 MeV neutron equivalent fluences in the order of $10^{16}$ cm$^{-2}$ was studied as an…
We report preliminary results from a synchrotron radiation study of Te inclusions in a large volume single crystal CdZnTe (CZT) coplanar-grid detector. The experiment was carried out by probing individual inclusions with highly collimated…
Distribution of charge induced by a gate voltage in a graphene strip is investigated. We calculate analytically the charge profile and demonstrate a strong(macroscopic) charge accumulation along the boundaries of a micrometers-wide strip.…
We study the emission of individual quantum dots in CdTe/ZnTe samples doped with a low concentration of Cr. In addition to dots with a photoluminescence (PL) split by the exchange interaction with a magnetic Cr atom, we observe another type…
A novel method to image charge is used to measure the diffusion coefficient of electrons in films of CdSe nanocrystals at room temperature. This method makes possible the study of charge transport in films exhibiting high resistances or…