Pulsed x-ray detector based on Fe doped β-Ga₂O₃ single crystal

Abstract

Abstract β -Ga 2 O 3 has shown great potential for x-ray detection. In this paper, we demonstrate a nanosecond fast-response metal–semiconductor–metal x-ray detection based on Fe doped semi-insulating β -Ga 2 O 3 single crystal. Material characterizations revealed that the iron substituting for gallium (Fe Ga ) and oxygen vacancy ( V O ) were the main defects within the β -Ga 2 O 3 and led to a high resistivity property of the material. The detector feathered a low dark current ∼270 pA (955 × pA cm −2 ) at 800 V and the x-ray detection process was slightly affected by the photodonductive gain. To x-ray illumination, the detector exhibited a low noise-equivalent dose rate ∼4.1 × 10 −7 Gy air s −1 Hz −0.5 , a response sensitivity of 23.2 nC Gy air −1 and a fast transient response (<20 ms). In addition, a pulsed x-ray detection in 50 ns was achieved and the time resolution of the β -Ga 2 O 3 detector was revealed to be <2 ns. The results demonstrate that the β -Ga 2 O 3 -based detector was promising for fast x-ray detection application.