Monte Carlo simulation of charge sharing effects in silicon and GaAs photon-counting X-ray imaging detectors
Responsible organisation
2004 (English)In: IEEE Transactions on Nuclear Science, ISSN 0018-9499, E-ISSN 1558-1578, Vol. 51, no 4, p. 1636-1640Article in journal (Refereed) Published
Abstract [en]
In this work we present a numerical study of charge sharing in photon counting X-ray imaging detectors. The study is based on charge transport simulations combined with a system level Monte Carlo simulation code to calculate the energy resolution of different pixel detector configurations. Our simulations show that the charge sharing is very sensitive to the electric field distribution in the device, and that the higher doping levels used in GaAs detectors reduce the effect of charge sharing significantly. Our study concludes that one of advantage's in using very heavy semiconductor materials in X-ray imaging detectors is the possibility to suppress charge sharing utilizing structures with much higher electric field. A 100 mum thick epitaxial GaAs detector absorbs 52% of the photons, while a 300 pin thick Silicon detector absorbs only 8% of the photons (30keV source). In addition to the superior stopping power, the GaAs detector has 5 times lower charge diffusion, resulting in superior spatial and energy resolution.
Place, publisher, year, edition, pages
IEEE , 2004. Vol. 51, no 4, p. 1636-1640
Keywords [sv]
Röntgen bildsensorer, fotonräkning, simulering
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
URN: urn:nbn:se:miun:diva-2322DOI: 10.1109/TNS.2004.832577ISI: 000223391600056Local ID: 2492ISBN: 0-7803-8257-9 (print)OAI: oai:DiVA.org:miun-2322DiVA, id: diva2:27354
Conference
IEEE Nuclear Science Symposium/Medical Imaging Conference, Oct 19-25, 2003, Portland, OR
Note
Nuclear Science Symposium/Medical Imaging Conference/13th International Workshop on Room-Temperature Semiconductor X-and Gamma-Ray Dectectors/Symposium on Nuclear Power Systems, Oct 19-25, 2003, portland, OR
2008-09-302008-09-302017-12-12Bibliographically approved