Friction Transfer of Teflon to Template the Growth of Organic Semiconductors

Abstract

Organic field effect transistors (OFET) based on the latest generation of p-type organic semiconductors (DNTTT, C10-DNTT) display excellent characteristics, with charge transport mobility of up to 10 cm2/Vs. These materials reach the quality levels of n-type oxide semiconductors (IGZO), potentially enabling the development of a complementary technology (CMOS) for low-cost electronic circuits on large area flexible foils. Examples of potential applications for such circuits are RFID tags, smart packaging, flexible displays and numerous biomedical applications. Among other things, the performance of OFET depends on the degree of crystallinity of the organic semiconductors. Higher ordering delivers better performance, and, the best OFETs are based on defect free single organic crystals. The production of thin films of defect free organic single crystals over large area is therefore highly desirable. This, however, remains a considerable challenge since the presence of only a few defects will negatively impact the spread of TFT characteristics. As the spread increases, the yield of circuits dramatically decreases. Templating that relies on a good match between the crystal structures of the substrate and the grown material is very well known in the field of epitaxial growth of inorganic materials. In the field of organic electronics, however, much remains to be done. Therefore we aim to develop a method to transfer a thin, uniform and aligned film of Polytetrafluoroethylene (PTFE) on the substrate as a template to grow organic semiconductors and increasing their degree of order following by making OFET. The influence of the PTFE layer on the performance of OFET is studied.