Structural Design of Flexible Electric Devices on Polymer Substrates and Application to Organic FET

Abstract

A structural design principle of flexible electric devices based on material mechanics is proposed, and it is applied to flexible organic field-effect transistors (OFETs). In order to prevent bending stress caused by deformation, we fabricated OFETs on a thickness-controlled polymer substrate. Polyimide precursor has been spin coated on a glass substrate and annealed. The channel layer of the OFET is pentacene deposited in a vacuum system. Correlations between curvature radius and electric characteristics have been evaluated. Consequently, the use of ultra thin film substrate is effective to control the strain on the deformed devices. Electrical property of the OFET, such as I_d-V_d characteristics is constant against the curvature radius. These results are promising for future flexible electronics technologies.