A Pentacene -Based Organic Mis Structures

Abstract

Organic devices based on pentacene thin film are demonstrated. Gold nanoparticles were used as the charge storage elements while pentacene has been used as the active semiconductor layer of Metal-Insulator-Semiconductor (MIS) structures. Polymethylmethacrylate (PMMA) formed the gate insulator. Four devices at different evaporation rates were fabricated and characterised by the atomic force microscopy and electrical characteristics. An optimal deposition rate was identified and supporting topographical images are presented. The device performance strongly correlates with the surface morphology, and the structural properties of the organic thin films have been investigated. The Atomic Force Microscopy (AFM) investigation of very slow evaporated pentacene showed larger grain sizes. Evaporating of gold electrodes on pentacene layers proved to change the morphology of the pentacene surface. The characteristics of bottom contact structures showed much-improved pentacene structures.