Latest Developments in Organic Semiconductors

M.A.Cowin

Advances in High Performance Organic Semiconductors for Flexible Displays

M.A.Cowin, R.Griffiths, K.Crowley.

SmartKem Ltd, Hexagon Tower, Delaunays Road, Blackley, Manchester, M9 8ZS United Kingdom. Tel.:+44 (0)161 795 3157, E-mail: m.cowin@smartkem.com

Keywords: Mobility, Organic Semiconductor, Flexible, Display. Abstract

We report on high mobility, high stability, solution processed p-type organic semiconductor (OSC) inks used in flexible Organic Thin Film Transistors (OTFTs). The results demonstrate that the semiconductor materials are readily processed at room temperature and in ambient conditions whilst affording high levels of OTFT performance, field effect mobilities up to ~ 4 cm2/Vs were measured. This high performance OSC is well suited to both the manufacturing process requirements and application performance requirements for future flexible OTFT backplane applications. of ~ 5 microns are desirable. In this work we focus on the spin coating method to deposit our high stability OSC ink and show how to fabricate OTFTs on a plastic substrate having mobilities greater than 3 cm2/Vs at short channel length. When considering the application of OTFTs to AMOLED displays, organic transistor materials have the capacity to offer many of the same advantages as OLEDs such as light weight, inherent mechanical flexibility, and compatibility with flexible substrates. Organic transistors are made often with similar tools and processes used for OLEDs, so a combined fabrication process may be more easily implemented and thus may offer additional manufacturing advantages [2]. Here we demonstrate a novel, high performance class of OSC inks with mobility superior to a-Si, good electrical stability and thermal stability in excess of 250ºC.

1. Introduction

Organic thin film transistors (OTFTs) have the potential for use as an alternative to silicon based or Indium Gallium Zinc Oxide based (IZGO) TFT backplanes for a wide range of display technologies. The...