Ultrathin and Ultrasensitive Direct X‐ray Detector Based on Heterojunction Phototransistors

Journal Article · 05 July 2021 · Advanced Materials

DOI: https://doi.org/10.1002/adma.202101717 · OSTI ID:1805099

Gao, Yuanhong ^[1]; Ge, Yongshuai ^[2]; Wang, Xinwei ^[3]; Liu, Jin ^[4]; Liu, Wenquan ^[5]; Cao, Yong ^[1]; Gu, Kaichen ^[6]; Guo, Zheng ^[3]; Wei, Yu‐Ming ^[4]; Zhou, Ni ^[1]; Yu, De ^[1]; Meng, Hong ^[3]; Yu, Xue‐Feng ^[1]; Zheng, Hairong ^[2]; Huang, Wei  ^[7]; Li, Jia ^[1]

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1. Materials Interfaces Center Shenzhen Institute of Advanced Technology Chinese Academy of Sciences Shenzhen 518055 P. R. China
2. Paul C. Lauterbur Research Center for Biomedical Imaging Shenzhen Institute of Advanced Technology Chinese Academy of Sciences Shenzhen 518055 P. R. China, Center for Medical Artificial Intelligence Shenzhen Institute of Advanced Technology Chinese Academy of Sciences Shenzhen 518055 P. R. China
3. School of Advanced Materials Shenzhen Graduate School Peking University Shenzhen 518055 P. R. China
4. State Key Laboratory of Optoelectronic Materials and Technologies School of Physics Sun Tat‐sen University Guangzhou 510275 P. R. China
5. Center for Opto‐Electronic Engineering and Technology Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences Shenzhen 518055 P. R. China
6. Department of Chemical and Biological Engineering Princeton University Princeton NJ 08544 USA
7. Frontiers Science Center for Flexible Electronics Xi'an Institute of Flexible Electronics (IFE) and Xi'an Institute of Biomedical Materials & Engineering Northwestern Polytechnical University 127 West Youyi Road Xi'an 710072 P. R. China; State Key Laboratory of Organic Electronics and Information Displays & Institute of Advanced Materials (IAM) Nanjing University of Posts & Telecommunications 9 Wenyuan Road Nanjing 210023 P. R. China; Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM) Nanjing Tech University (NanjingTech) South Puzhu Road Nanjing 211816 P. R. China

Abstract Most contemporary X‐ray detectors adopt device structures with non/low‐gain energy conversion, such that a fairly thick X‐ray photoconductor or scintillator is required to generate sufficient X‐ray‐induced charges, and thus numerous merits for thin devices, such as mechanical flexibility and high spatial resolution, have to be compromised. This dilemma is overcome by adopting a new high‐gain device concept of a heterojunction X‐ray phototransistor. In contrast to conventional detectors, X‐ray phototransistors allow both electrical gating and photodoping for effective carrier‐density modulation, leading to high photoconductive gain and low noise. As a result, ultrahigh sensitivities of over 10 ⁵  μC Gy _air ⁻¹  cm ⁻² with low detection limit are achieved by just using an ≈50 nm thin photoconductor. The employment of ultrathin photoconductors also endows the detectors with superior flexibility and high imaging resolution. This concept offers great promise in realizing well‐balanced detection performance, mechanical flexibility, integration, and cost for next‐generation X‐ray detectors.

• Sponsoring Organization: USDOE
• Grant/Contract Number: SC0012704
• OSTI ID: 1805099
• Journal Information: Advanced Materials, Journal Name: Advanced Materials Journal Issue: 32 Vol. 33; ISSN 0935-9648
• Publisher: Wiley Blackwell (John Wiley & Sons)Copyright Statement
• Country of Publication: Germany
• Language: English