Performance improvement of pentacene-based organic thin-film transistor with the planar bottom-contact structure and the bi-layer gate dielectric

This study reports the performance improvement of pentacene-based organic thin-film transistor (OTFT) with the proposed planar bottom-contact structure and the bi-layer gate dielectric. The planar bottom-contact (pBC) structure can provide a continuous plane to enhance the grain growth continuity of pentacene layer, further improving the charge carriers injection or/and transportation near the edge of source/drain electrodes; hence, the pBC structure reduces the contact resistance between the organic semiconductor and the source/drain metals, resulting in the improved field-effect mobility. In addition, the bi-layer gate dielectric is used for the etching selectivity to control the planarization process well.