High mobility AlGal\l/GaN devices for beta(-)-dosimetry

作者：Schmid Martin; Howgate John; Ruehm Werner; Thalhammer Stefan^*

来源：Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment , 2016, 819: 14-19.

DOI：10.1016/j.nima.2016.02.036

• beta Emitters
• GaN
• Radiation detectors
• Monte Carlo simulations

There is a high demand in modern medical applications for dosimetry sensors with a small footprint allowing for unobtrusive or high spatial resolution detectors. To this end we characterize the sensoric response of radiation resistant high mobility AlGaN/GaN semiconductor devices when exposed to beta-emitters. The samples were operated as a floating gate transistor, without a field effect gate electrode, thus excluding any spurious effects from 1 beta-particle interactions with a metallic surface covering. We demonstrate that the source-drain current is modulated in dependence on the kinetic energy of the incident beta-particles. Here, the signal is shown to have a linear dependence on the absorbed energy calculated from Monte Carlo simulations. Additionally, a stable and reproducible sensor performance as a beta-dose monitor is shown for individual radioisotopes. Our experimental findings and the characteristics of the AlGaN/GaN high mobility layered devices indicate their potential for future applications where small sensor size is necessary, like for instance brachytherapy.

• 出版日期2016-5-21