Enhanced Performance of Organic Field-Effect Transistors by a Molecular Dopant with High Electron Affinity

Organic field-effect transistors (OFETs) are attractive for next-generation electronics, while doping plays an important role in their performance optimization. In this work, a soluble molecular dopant with high electron affinity, CN6-CP, is investigated to manipulate the performance of OFETs with a p-type organic semiconductor as the transport layer. The performance of the model 2,7-didodecyl[1]benzothieno[3,2-b][1]benzothiophene (C12-BTBT) bottom-gate top-contact (BGTC) OFETs is greatly optimized upon doping by CN6-CP, and the field-effect mobility is improved from 5.5 to 11.1 cm²V^-1s^-1, with a widely tunable threshold voltage from -40 to +5 V. Improvements in performance also appear in CN6-CP doped BGBC OFETs. As compared with commonly used molecular dopant F4-TCNQ, CN6-CP exhibits excellent doping effects and great potential for organic electronic applications.