title: Ultrahigh near infrared photoresponsive organic field-effect transistors with lead phthalocyanine/C60 heterojunction on poly(vinyl alcohol) gate dielectric.
abstract: Performances of photoresponsive organic field-effect transistors (photOFETs) operating in the near infrared (NIR) region utilizing SiO2 as the gate dielectric is generally low due to low carrier mobility of the channel. We report on NIR photOFETs based on lead phthalocyanine (PbPc)/C60 heterojunction with ultrahigh photoresponsivity by utilizing poly(vinyl alcohol) (PVA) as the gate dielectric. For 808 nm NIR illumination of 1.69 mW cm(-2), an ultrahigh photoresponsivity of 21 A W(-1), and an external quantum efficiency of 3230% were obtained at a gate voltage of 30 V and a drain voltage of 80 V, which are 124 times and 126 times as large as the reference device with SiO2 as the gate dielectric, respectively. The ultrahigh enhancement of photoresponsivity is resulted from the huge increase of electron mobility of C60 film grown on PVA dielectric. AFM investigations revealed that the C60 film grown on PVA is much smooth and uniform and the grain size is much larger than that grown on SiO2 dielectric, which together results in four orders of magnitude increase of the field-effect electron mobility of C60 film.
authors: Institute of Microelectronics, School of Physical Science and Technology, Lanzhou University, South Tianshui Road 222#, Lanzhou 730000, People's Republic of China.
authors: Lei
authors: L
authors: Sun
authors: Jianping
authors: J
authors: Zhang
authors: Feiyu
authors: F
authors: Zhao
authors: Xiao
authors: X
authors: Luo
authors: Wenli
authors: W
authors: Lv
authors: Yao
authors: Y
authors: li
authors: Qiang
authors: Q
authors: Ren
authors: Zhanwei
authors: Z
authors: Wen
authors: Yingquan
authors: Y
authors: Peng
authors: Xingyuan
authors: X
authors: Liu