Highly responsive broadband Si-based MoS2 phototransistor on high-k dielectric

作     者：Ali IMRAN Xin HE Jiwei LIU Qinghai ZHU Muhammad SULAMAN Fei XUE Mingsheng XU Deren YANG 

作者机构：College of Integrated CircuitsState Key Laboratory of Silicon and Advanced Semiconductor MaterialsZhejiang University ZJU-Hangzhou Global Scientific and Technological Innovation Centre School of Materials Science and EngineeringState Key Laboratory of Silicon and Advanced Semiconductor MaterialsZhejiang University Beijing Key Lab of Nanophotonics and Ultrafine Optoelectronic SystemsSchool of PhysicsBeijing Institute of Technology 

出 版 物：《Science China(Information Sciences)》 (中国科学:信息科学(英文版))

年 卷 期：2024年第67卷第6期

页      面：180-189页

核心收录：

学科分类：0808[工学-电气工程] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0812[工学-计算机科学与技术（可授工学、理学学位）] 

基　　金：supported by National Natural Science Foundation of China (Grant Nos. 62090030, 62090031, 62274145) Natural Science Foundation of Zhejiang Province, China (Grant No. LZ20F040001) National Key R&D Program of China (Grant No. 2021YFA1200502) Fund of China Scholarship Council (CSC) 

主　　题：photogating photoconduction two-dimensional materials high $~k$ dielectric carrier scattering phototransistor 

摘      要：The demand for photodetectors and image sensors has grown exponentially in the past decade in biomedical, security surveillance, robotics, automotive, quality control, image recognition, and military applications, due to their superior quality, broadband detection, lower noise, and economic viability. Here,we report a MoS2channel-based phototransistor over an HfO2/n-Si substrate isolated by an h BN layer. The high photoresponse is achieved through the integration of the photoconduction, photogating, and mobility enhancement process by utilizing excellent features of MoS2, HfO2/Si, and h BN. The capacitive coupling of the photogenerated carriers by high-k dielectric HfO2leads to modulation of MoS2Fermi level due to electrostatic doping. Furthermore, the MoS2also contributes to the photogeneration of carriers due to its semiconducting nature, leading to additional photocurrent. Ultimately, the combination of photogating,photoconduction, and swift carrier extraction with remarkable mobility of 11.65 cm2· V-1· s-1results in high responsivity, external quantum efficiency, and detectivity of 4.5 × 10～8A · W-1, 0.72 × 10～6, and 6.20× 1016Jones at 266 nm illumination, respectively. The device also demonstrates broadband photoresponse from 266–1000 nm wavelengths. The high responsivity distinguishes the potential of our device for the future of optoelectronics and broadband image sensing applications.