A striking performance improvement of fullerene n-channel field-effect transistors via synergistic interfacial modifications. (17th September 2015)

• Record Type: Journal Article
• Authors: Du, Lili; Luo, Xiao; Wen, Zhanwei; Zhang, Jianping; Sun, Lei; Lv, Wenli; Li, Yao; Zhao, Feiyu; Zhong, Junkang; Ren, Qiang; Huang, Fobao; Xia, Hongquan; Peng, Yingquan
• Is Part Of: Journal of physics. Volume 48:Number 40(2015)
• Publication Date: 2015-09-17
• Subjects: fullerene -- n-channel -- organic field-effect transistor -- interfacial modifications -- gap state -- time stability; Physics -- Periodicals; 530
• DOI: 10.1088/0022-3727/48/40/405105
• Languages: English
• ISSNs: 0022-3727

Abstract

Abstract: For fullerene based n-channel transistors, remarkably improved device characteristics were achieved via charge injection and transport interfacial synergistic modifications using low-cost aluminium source/drain electrodes. Compared with the reference device without any modifications (device A), the as-fabricated transistor (device H) showed a dramatic improvement of saturation mobility from 0.0026 to 0.3078 cm 2 V −1 s −1 with a maximum on–off current ratio of 10 6 and a minimum subthreshold slope of 1.52 V decade −1 . AFM and XRD analysis manifested that the deposited C60 films on PVA/OTS successive-modified SiO2 substrate were highly dense polycrystalline and uniform with larger crystalline grain and less grain boundary. A gap state assisted electron injection mechanism was proposed to explicate the enhanced electrical conductivity considering BCP modification for charge injection interface, which has been well corroborated by a diode-based injection experiment and a theoretical calculation of contact resistances. We further demonstrated the application of the concept modification method to enable comparative time-stable operation of fullerene n-channel transistors. Given many key merits, we believed that this general method using multi-interface modifications could be extended to fabricate other n-channel OFETs with superior electrical performance and stability.