【Epitaxy Papers】High-performance X-ray detector based on amorphous Ga₂O₃ film

      Researchers from the Changchun University of Science and Technology have published a dissertation titled " High-performance X-ray detector based on amorphous Ga₂O₃ film " in Journal of Alloys and Compounds.

Abstract

      X-ray detectors are widely used in medical imaging, safety inspection, industrial non-destructive testing, and other fields. Amorphous Ga₂O₃ (a-Ga₂O₃) has become a candidate for next-generation X-ray detectors due to its high breakdown voltage and excellent radiation stability. However, the development of high-performance a-Ga₂O₃ detectors with a broad photon energy range is still challenging. In this work, a-Ga₂O₃ devices with coplanar metal-semiconductor-metal (MSM) structure were fabricated. Special attention was paid to the influence of air ionization on the detection performance of direct detectors and the analysis of multiple ionization mechanisms of hard X-rays. Optimizing the Compton scattering path in the active layer resulted in impressive performance of the detector over a wide photon energy range (40-120 keV) in a 1 kPa test environment. At a bias voltage of 80 V and the dose rate of 1.94 mGy_air s^-1 (40 kV), the detector achieved a 25 I_x-ray/I_dark value and a sensitivity of 21078 μC mGy_air⁻¹ cm⁻³. With a further increase in the dose rate to 14.27 mGy_air s^-1 (120 kV), the detector demonstrated a 795 I_x-ray/I_dark value and a sensitivity of up to 83299 μC mGy_air⁻¹ cm⁻³. These results prove that micro-sized a-Ga₂O₃ films have excellent application prospects for hard X-ray detection after reducing the effect of air ionization.

DOI：

https://doi.org/10.1016/j.jallcom.2025.183783