Solar-blind imaging based on 2-inch polycrystalline diamond photodetector linear array

• Published in: Carbon (New York) Vol. 173; pp. 427 - 432
• Main Authors: Zhang, Zhenfeng, Lin, Chaonan, Yang, Xun, Tian, Yongzhi, Gao, Chaojun, Li, Kaiyong, Zang, Jinhao, Yang, Xigui, Dong, Lin, Shan, Chongxin
• Format: Journal Article
• Language: English
• Published: New York Elsevier Ltd 01.03.2021; Elsevier BV
• Subjects: carbon; Carrier mobility; Cut off wavelength; Diamonds; electric field; Electric fields; electronics; Energy gap; Heat conductivity; Linear arrays; Optoelectronics; Photodetector linear array; Photometers; Photovoltaic cells; Polycrystalline diamond; Polycrystals; radiation resistance; Radiation tolerance; Response time; semiconductors; Single crystals; Solar energy; Solar-blind imaging; Thermal conductivity; Thermal resistance; Thermal stability; Ultraviolet detectors; wavelengths; Polycrystalline diamond; Photodetector linear array; Solar-blind imaging
• ISSN: 0008-6223; 1873-3891
• DOI: 10.1016/j.carbon.2020.11.013

Diamond is a promising ultrawide-bandgap semiconductor, which has drawn much attention in deep-ultraviolet optoelectronics and high-power electronics, due to its unique properties, including the highest thermal conductivity, strong radiation resistance, high breakdown electric field, chemical and thermal stability, and high carrier mobility. However, the optoelectronics applications have been restricted greatly by the small growth size of the single-crystal diamond. In this work, we demonstrate a solar-blind photodetector linear array based on high-quality 2-inch polycrystalline diamond, which has the advantage of large-area growth. The photodetector cells exhibit good uniformity, a responsivity of 45 mA/W at 228 nm with a cut-off wavelength of 240 nm, and a short response time of <20 μs. Clear solar-blind images are obtained by using the photodetector linear array as sensing units. The results reported in this work promise the potential applications of polycrystalline diamond in deep-ultraviolet photodetectors. An electronic-grade 2-inch polycrystalline diamond free-standing film grown by microwave plasma chemical vapor deposition (MPCVD), from which a diamond photodetector linear array has been developed for solar-blind imaging. [Display omitted]