[TuP3G] Oxide Materials & Devices

[TuP3G-08] High-Sensitivity X-ray Detection Using Ga₂O₃-Based Devices

〇Sunjae Kim^1,2, Hyeong-Yun Kim¹, Dowon Lee¹, JungHun Choi¹, Ji-Hyeon Park¹, Wan Sik Hwang², Dae-Woo Jeon¹ (1. Korea Inst. of Ceramic Eng. and Tech. (Korea), 2. Korea Aerospace univ. (Korea))

This study evaluates the performance of a β-Ga₂O₃-based X-ray detector for discriminating the number of stacked A4 sheets under X-ray irradiation. The device was fabricated using an 11-µm-thick Si-doped n-type β-Ga₂O₃ epitaxial layer grown on an Sn-doped β-Ga₂O₃ substrate, forming Schottky and Ohmic contacts. The detector exhibits clear rectifying behavior with a high on/off current ratio (>10⁶) and low leakage current. The attenuation behavior follows the Beer–Lambert law, showing an exponential decrease in photocurrent with increasing cellulose thickness. Additionally, the device demonstrates fast and stable temporal responses with rise and fall times of 0.15 s and 0.13 s, respectively, independent of attenuation level. The detector successfully distinguishes up to seven stacked A4 sheets, highlighting its potential for low-dose X-ray imaging, document authentication, and material inspection applications.