Wang Jing, Zhou Leidang, Chen Liang, Zhang Silong, Wang Fangbao, Fan Tingting, Chen Zhuo, Bai Song, Ouyang Xiaoping
School of Microelectronics, Xidian University, Xi'an 710071, China.
Northwest Institute of Nuclear Technology, Xi'an 710024, China.
Micromachines (Basel). 2024 Dec 24;16(1):2. doi: 10.3390/mi16010002.
In this paper, a silicon carbide (SiC) phototransistor based on an open-base structure was fabricated and used as a radiation detector. In contrast to the exposed and thin sensitive region of traditional photo detectors, the sensitive region of the radiation detector was much thicker (30 μm), ensuring the high energy deposition of radiation particles. The response properties of the fabricated SiC npn radiation detector were characterized by high-energy X-ray illumination with a maximum X-ray photon energy of 30 keV. The SiC npn detector featured stable and clear response to the X-ray within 0.0766 Gy∙s to 0.766 Gy∙s below 300 V. Due to to the low leakage current of less than 1 nA and the fully depleted sensitive region, the bipolar-transistor-modeled SiC npn detector exhibited a clear common-emitter current gain of 5.85 at 200 V (under 0.383 Gy∙s), where the gain increased with bias voltage due to the Early effect and reached 7.55 at 300 V. In addition, the transient response of the SiC npn detector revealed a longer delay time than the SiC diode of the same size, which was associated with the larger effective capacitance of the npn structure. The npn detector with internal gain showed great potential in radiation detection.
本文制备了一种基于开路基极结构的碳化硅（SiC）光电晶体管，并将其用作辐射探测器。与传统光电探测器暴露且薄的敏感区域不同，该辐射探测器的敏感区域要厚得多（30μm），可确保辐射粒子的高能量沉积。通过最大X射线光子能量为30keV的高能X射线照射来表征所制备的SiC npn辐射探测器的响应特性。SiC npn探测器在300V以下对0.0766 Gy∙s至0.766 Gy∙s的X射线具有稳定且清晰的响应。由于漏电流小于1nA且敏感区域完全耗尽，基于双极晶体管模型的SiC npn探测器在200V（0.383 Gy∙s下）时共发射极电流增益为5.85，由于厄利效应，增益随偏置电压增加，在300V时达到7.55。此外，SiC npn探测器的瞬态响应显示其延迟时间比相同尺寸的SiC二极管更长，这与npn结构较大的有效电容有关。具有内部增益的npn探测器在辐射探测方面具有巨大潜力。
