Tuning on threshold voltage of organic field-effect transistor with a copper oxide layer

Organic field-effect transistors (OFETs) based on the pentacene semiconductor with an embedded thin layer of copper oxide (CuO) were investigated. The drain current of OFETs with a thin CuO layer embedded in pentacene increases more than three times compared to that of traditional OFETs without the CuO layer, and the threshold voltage shifts from -17.5 V to -7.9 V. A possible mechanism for OFETs with the CuO layer was discussed via analysis of electron transfer near the contact between CuO and pentacene. OFETs with the CuO layer exhibit an interesting result of a systematic tuning of threshold voltage by controlling the initial voltage of gate-to-source upon scanning transfer curves. (C) 2011 Elsevier B. V. All rights reserved.