Regular Article

Performance improvement of organic thin film transistors by using active layer with sandwich structure

¹ College of Communication Engineering, Chongqing University, Chongqing 400044, P.R. China
² School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu 610054, P.R. China

^a e-mail: zjl4062002@163.com
^b e-mail: lhui@uestc.edu.cn

Received: 8 May 2017
Revised: 20 June 2017
Accepted: 21 June 2017
Published online: 2 August 2017

Abstract

We report organic thin film transistors (OTFTs) with pentacene/fluorinated copper phthalo-cyanine (F₁₆CuPc)/pentacene (PFP) sandwich configuration as active layers. The sandwich devices not only show hole mobility enhancement but also present a well control about threshold voltage and off-state current. By investigating various characteristics, including current-voltage hysteresis, organic film morphology, capacitance-voltage curve and resistance variation of active layers carefully, it has been found the performance improvement is mainly attributed to the low carrier traps and the higher conductivity of the sandwich active layer due to the additional induced carriers in F₁₆CuPc/pentacene. Therefore, using proper multiple active layer is an effective way to gain high performance OTFTs.