Imaging with polycrystalline mercuric iodide detectors using VLSI readout

Citation
R. Turchetta et al., Imaging with polycrystalline mercuric iodide detectors using VLSI readout, NUCL INST A, 428(1), 1999, pp. 88-94
Citations number
12
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Spectroscopy /Instrumentation/Analytical Sciences","Instrumentation & Measurement
Journal title
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
ISSN journal
0168-9002 → ACNP
Volume
428
Issue
1
Year of publication
1999
Pages
88 - 94
Database
ISI
SICI code
0168-9002(19990601)428:1<88:IWPMID>2.0.ZU;2-N
Abstract
Potentially low cost and large area polycrystalline mercuric iodide room-te mperature radiation detectors, with thickness of 100-600 mu m have been suc cessfully tested with dedicated low-noise, low-power mixed signal VLSI elec tronics which can be used for compact, imaging solutions. The detectors are fabricated by depositing HgI2 directly on an insulating substrate having e lectrodes in the form of microstrips and pixels with an upper continuous el ectrode. The deposition is made either by direct evaporation or by screen p rinting HgI2 mixed with glue such as Poly-Vinyl-Butiral. The properties of these first-generation detectors are quite uniform from one detector to ano ther. Also for each single detector the response is quite uniform and no ch arge loss in the inter-electrode space have been detected. Because of the l ow cost and of the polycrystallinity, detectors can be potentially fabricat ed in any size and shape, using standard ceramic technology equipment, whic h is an attractive feature where low cost and large area applications are n eeded. The detectors which act as radiation counters have been tested with a beta source as well as in a high-energy beam of 100 GeV muons at CERN,con nected to VLSI, low noise electronics. Charge collection efficiency and uni formity have been studied. The charge is efficiently collected even in the space between strips indicating that fill factors of 100% could be reached in imaging applications with direct detection of radiation. Single photon c ounting capability is reached with VLSI electronics. These results show the potential of this material for applications demanding position sensitive, radiation resistant, room-temperature operating radiation detectors, where position resolution is essential, as it can be found in some applications i n high-energy physics, nuclear medicine and astrophysics. (C) 1999 Elsevier Science B.V. All rights reserved.