A highly tunable photoelectric response of graphene field-effect transistor with lateral P–N junction in channel. (22nd October 2022)

• Record Type: Journal Article
• Authors: Zhang, Yantao; Wang, Zhong; Zhang, Guohe; Wang, Xiaoli; Han, Chuanyu; Li, Xin; Liu, Weihua
• Is Part Of: Nanotechnology. Volume 33:Number 43(2022)
• Publication Date: 2022-10-22
• Subjects: photoelectric response -- GFET -- P–N junction -- polarity of photocurrent -- back-gate voltage; Nanotechnology -- Periodicals; Nanotechnology -- Periodicals; Nanotechnology; Publications périodiques; Nanotechnologies; Periodicals; 620.5
• DOI: 10.1088/1361-6528/ac82f7
• Languages: English
• ISSNs: 0957-4484

Abstract

Abstract: This paper reports a highly tunable photoelectric response of graphene field-effect transistor (GFET) with lateral P–N junction in channel. The poly(sulfobetaine methacrylate) (PSBMA) provides strong N-type doping on graphene due to the dipole moment of pendent groups after ultraviolet annealing in high vacuum. A lateral P–N junction is introduced into the channel of the GFET by partially covering the graphene channel with PSBMA. With such P–N junction in the channel, the GFET exhibits a highly tunable photoelectric response over a wide range of exciting photon wavelength. With a lateral P–N junction in the channel, the polarity of photocurrent ( I ph ) of the GFET switches three times as the back-gate voltage ( V BG ) scan over two Dirac-point voltages. The underlying physical mechanism of photoelectric response is attributed to photovoltaic and photo-induced bolometric effect, which compete to dominating I ph at various V BG . This provides a possible strategy for designing new phototransistors or optoelectronic device in the future.