Eur. Phys. J. Appl. Phys. (2015) 70: 20102
https://doi.org/10.1051/epjap/2015150149

Improve the n-type performance in organic heterojunction transistors by controlling thickness of copper phthalocyanine

¹ Department of Electronic Engineering, College of Communication and Electronics, Chongqing University, Chongqing 400044, P.R. China
² State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054, P.R. China

^a e-mail: zjl4062002@163.com

Received: 11 March 2015
Revised: 9 April 2015
Accepted: 13 April 2015
Published online: 19 May 2015

Abstract

N-type C₆₀ thin film transistors with heterojunction were fabricated by introducing copper phthalocyanine (CuPc) modifying layer between polymer dielectrics and C₆₀ semiconductor. Comparing with conventional organic thin film transistors (OTFTs) based on single C₆₀ layer, such devices can not only boost the electron mobility up to 3 times, but also well control threshold voltage V_T and off current I_off by optimizing CuPc thickness. The performance improvement can be attributed to the increase of free electron carriers by the dipole effect at the C₆₀/CuPc interface, and better C₆₀ film quality grown upon CuPc.