Organic field-effect transistors integrated with Ti₂CT_x electrodes

Recently, MXenes, which are two-dimensional early transition metal carbides and carbonitrides, have attracted wide attention because of their unique properties. In this study, the electrode applications of Ti₂CT_x, a member of the MXene family, in pentacene organic field-effect transistors (OFETs) are assessed. Kelvin probe force microscopy analysis was performed to determine the work function of Ti₂CT_x, which is estimated to be around 5.1 eV. Devices with Ti₂CT_x electrodes and pentacene channels were fabricated and their electronic performances were evaluated. The contact resistance between Ti₂CT_x and pentacene is as low as 3 kΩ cm, superior to those of other reported electrode materials. The temperature-dependent current-voltage transfer characteristics of the devices were used to extract activation energy, estimated to be 0.17 eV. This activation energy value is much lower than those of other electrode materials and demonstrates that Ti₂CT_x is a promising electrode for high performance OFET applications.