Comparative analysis of doping and injection effects with discontinuous organic pn-heterojunctions in OFETs. (October 2020)

• Record Type: Journal Article
• Authors: Liu, Xueqiang; Kang, Haobo; Qiao, Zhen; Liu, Yanyan
• Is Part Of: Solid state communications. Volume 320(2020)
• Publication Date: 2020-10
• Subjects: Organic field-effect transistor -- Organic pn-heterojunction -- Channel doping -- Electrode injection -- Tunneling effect; Solid state chemistry -- Periodicals; Solid state physics -- Periodicals; Chimie de l'état solide -- Périodiques; Physique de l'état solide -- Périodiques; 530.41
• DOI: 10.1016/j.ssc.2020.114013
• Languages: English
• ISSNs: 0038-1098

Abstract

Abstract: OFETs with discontinuous accumulative heterojunction have been fabricated with the pair of pentacene and F16 CuPc. Four structures were designed to compare the channel doping and enhancing electrode injection effects both caused by carrier accumulation at different positions in OFETs. The tunneling mechanism of enhancing electrode injection efficiency is further investigated. Moreover, the E LUMO of F16 CuPc is pinned to the E F of pentacene by employing the organic-organic interface energy level alignment (OOI ELA) theory, which demonstrates the significant increase of carrier concentration theoretically at both sides of the organic pn-heterojunction surface. Due to the dual modification effects of channel doping and enhancing electrode injection, the mobility of pentacene OFET has reached at 0.2 cm 2 /Vs, which is 14.4 times higher than the pristine device. Highlights: TThe tunneling mechanism of the enhanced electrode injection efficiency with discontinuous pn-heterojunction was investigated further. We revealed the reason of the dramatic increase of carrier concentration in organic layer. Four OFET structures were employed for the comparison research on channel doping and electrode injection effects.