TITLE

Suitability of epitaxial GaAs for x-ray imaging

AUTHOR(S)
Sun, G. C.; Talbi, N.; Verdeil, C.; Bourgoin, J. C.
PUB. DATE
September 2004
SOURCE
Applied Physics Letters;9/20/2004, Vol. 85 Issue 12, p2399
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Because the rate of indirect photon-electron conversion for scintillator materials coupled with arrays of photodiodes is at least 25 times smaller than the rate of direct conversion, we examine the conditions to be fulfilled by semiconductors undergoing such direct conversion to be applied to x-ray imaging. Bulk grown materials are not well suited to this application, because large defect concentrations give rise to strongly nonuniform electronic properties. We argue that only epitaxial layers are suitable for use as imaging devices and we illustrate our argument using the case of thick epitaxial GaAs layers. Detectors made with such layers exhibit a good energy resolution, a charge collection efficiency which approaches 1, linearity over more than three orders of amplitude, no afterglow (a response time shorter than 20 μs), and no charge-induced polarization effects.
ACCESSION #
14546652

 

Related Articles

  • Recent developments in the avalanche photodiode x-ray detector for timing and fast counting... Kishimoto, Shunji // Review of Scientific Instruments;Feb1995, Vol. 66 Issue 2, p2314 

    Describes an avalanche photodiode detector that was developed for x-ray timing measurements. Design of the apparatus; Bunch-purity measurements; Fast counting measurements.

  • Review on X-ray Detectors Based on Scintillators and CMOS Technology. Rocha, Jose G.; Lanceros-Mendez, Senentxu // Recent Patents on Electrical Engineering;Jan2011, Vol. 4 Issue 1, p16 

    This article describes the theoretical basis, design and implementation of X-ray microdetectors based on scintillating materials and CMOS technology. The working principle of such microdetectors consists in the absorption of X-rays by scintillators, which produce visible light. The visible light...

  • Light emission efficiency of GdAlO3:Ce (GAP:Ce) powder screens under X-ray radiography conditions. Toutountzis, A.; Michail, C.; Valais, I.; David, S.; Kalyvas, N.; Liaparinos, P.; Kandarakis, I. // e-Journal of Science & Technology;2009, Vol. 4 Issue 3, p23 

    The aim of this study was to evaluate the performance of GdAlO3:Ce powder scintillator screens for use in medical imaging applications. This powder phosphor, also known as GAP:Ce scintillator, is a non-hygroscopic material, emitting blue light with short decay time and it has never been used in...

  • Lanthanum Chloride Scintillator for X-ray Detection. Martin, T.; Allier, C.; Bernard, F. // AIP Conference Proceedings;2007, Vol. 879 Issue 1, p1156 

    In this presentation we describe the testing of a new cerium doped Lanthanum Chloride crystal (LaCl3:Ce), which makes an excellent scintillation material for X-ray counting applications. Detailed measurements were taken to determine the properties of the scintillator over an energy range of 5 to...

  • Soft x-ray array system with variable filters for the DIII-D tokamak. Hollmann, E. M.; Chousal, L.; Fisher, R. K.; Hernandez, R.; Jackson, G. L.; Lanctot, M. J.; Pidcoe, S. V.; Shankara, J.; Taussig, D. A. // Review of Scientific Instruments;Nov2011, Vol. 82 Issue 11, p113507 

    Recent upgrades to the soft x-ray (SXR) array system on the DIII-D tokamak are described. The system consists of two 32-channel arrays at one toroidal location and three toroidally distributed 12-channel arrays. The 32-channel arrays have been completely rebuilt to allow the switching of SXR...

  • A Streak-Camera Monitor for Hard X Rays. Kravchenko, A. G.; Litvin, D. N.; Murugov, V. M.; Senik, A. V. // Instruments & Experimental Techniques;Mar/Apr2004, Vol. 47 Issue 2, p247 

    The instrument is designed on the basis of a fast scintillator and a high-speed image-converter tube for hard X and ? rays (=10 keV). Using a scintillator, it is possible to obtain an almost constant spectral response over an energy range of 40�1000 keV. The time resolution of the camera is...

  • Spectral and kinetic characteristics of CdI2 and CdI2:Pb scintillators. Novosad, S. S.; Matviishin, I. M.; Novosad, I. S.; Novosad, O. S. // Journal of Applied Spectroscopy;Nov2008, Vol. 75 Issue 6, p826 

    We have studied the effect of lead dopant on the optical absorption, photoluminescence, and x-ray luminescence spectra, and the scintillation characteristics of CdI2 at room temperature. The crystals for the study were grown by the Stockbarger-Bridgman method. Activation of CdI2 from the melt by...

  • The luminescence of BaF2 nanoparticles upon high-energy excitation. Vistovskyy, V. V.; Zhyshkovych, A. V.; Halyatkin, O. O.; Mitina, N. E.; Zaichenko, A. S.; Rodnyi, P. A.; Vasil'ev, A. N.; Gektin, A. V.; Voloshinovskii, A. S. // Journal of Applied Physics;2014, Vol. 116 Issue 5, p054308-1 

    The dependence of X-ray excited luminescence intensity on BaF2 nanoparticle size was studied. A sharp decrease of self-trapped exciton luminescence intensity was observed when the nanoparticle size is less than 80 nm. The main mechanism of the luminescence quenching is caused by the escape of...

  • Light emission efficiency and imaging performance of YAlO: Ce (YAG: Ce) powder screens under diagnostic radiology conditions. Cavouras, D.; Kandarakis, I.; Nikolopoulos, D.; Kalatzis, I.; Kagadis, G.; Kalivas, N.; Episkopakis, A.; Linardatos, D.; Roussou, M.; Nirgianaki, E.; Margetis, D.; Valais, I.; Sianoudis, I.; Kourkoutas, K.; Dimitropoulos, N.; Louizi, A.; Nomicos, C.; Panayiotakis, G. // Applied Physics B: Lasers & Optics;Jun2005 Part 1, Vol. 80 Issue 7, p923 

    In this study YAlO: Ce powder scintillator was evaluated for use in X-ray imaging detectors. This phosphor, also known as YAG: Ce scintillator or P-46 phosphor, is a non-hygroscopic, emitting green light with very short decay time. These properties are very attractive for X-ray imaging. YAlO: Ce...

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics