Anodically Produced Alumina Dielectric for Organic Electronic Devices

Abstract

The properties of the dielectric strongly influence the performance of organic electronic devices. We see the influence of the roughness on the dielectric, used in the fabrication of Organic thin film transistor (OTFT).OTFTs are particularly interesting as their fabrication processes are much less complex compared with conventional Si technology, which involves high-temperature and high-vacuum deposition processes and sophisticated photolithographic patterning methods. In general, lowtemperature deposition and solution processing can replace the more complicated processes involved in conventional Si technology. The achieved hole mobilities went up to 5 cm 2 /Vs in the case of pentacene. Major influences on the mobility have been the purification, deposition conditions of the organic semiconductor and the properties of the dielectric surface. Variations in the surface chemistry cause large changes in the mobility of the OTFT. In addition, several publications mention a reduction in mobility due to increased surface roughness. In this paper, we show experimental results that quantify the influence of the roughness of the dielectric on the mobility.