USE OF EPITAXIAL GALLIUM ARSENIDE IN DETECTORS

摘要

The results of investigations of semiconductor detectors on the basis of epitaxial layers of gallium arsenide for detecting x rays and low-energy radiation are examined. It is shown that epitaxial layers ranging in thickness from 60 to 300 μm with current carrier density ≤ 5.10~(13) cm~(-3) and electron mobility ≥ 6000 cm~2 /(V·sec) at 300 K hold promise for such detectors. A new type of photovoltaic x-ray detector based on the epitaxial structures p~+-n-n~i-n~+ GaAs is described. Such detectors possess high charge collection efficiency with zero bias at room temperature and can operate in two regimes - counting and current integration - and will substantially expand the dynamical range of image formation when used in scanning systems.