Towards low-voltage organic thin film transistors (OTFTs) with solution-processed high-&lt;em&gt;k&lt;/em&gt; dielectric and interface engineering

Yaorong Su,Weiguang Xie,Jianbin Xu

doi:10.3934/matersci.2015.4.510

Abstract

Although impressive progress has been made in improving the performance of organic thin film transistors (OTFTs), the high operation voltage resulting from the low gate capacitance density of traditional SiO2 remains a severe limitation that hinders OTFTs'development in practical applications. In this regard, developing new materials with high-k characteristics at low cost is of great scientific and technological importance in the area of both academia and industry. Here, we introduce a simple solution-based technique to fabricate high-k metal oxide dielectric system (ATO) at low-temperature, which can be used effectively to realize low-voltage operation of OTFTs. On the other hand, it is well known that the properties of the dielectric/semiconductor and electrode/semiconductor interfaces are crucial in controlling the electrical properties of OTFTs. By optimizing the above two interfaces with octadecylphosphonic acid (ODPA) self-assembled monolayer (SAM) and properly modified low-cost Cu, obviously improved device performance is attained in our low-voltage OTFTs. Further more, organic electronic devices on flexible substrates have attracted much attention due to their low-cost, rollability, large-area processability, and so on. Basing on the above results, outstanding electrical performance is achieved in flexible devices. Our studies demonstrate an effective way to realize low-voltage, high-performance OTFTs at low-cost.

Highlights

During the past decades, rapid progress has been achieved in both the designing of novel organic semiconducting materials and the optimization of device fabrication techniques for organic thin film transistors (OTFTs) due to their potential applications in low-cost and flexible consumable electronics, such as such as RFID tags, flat panel displayers, and portable electronics [1,2,3,4]
Abstract: impressive progress has been made in improving the performance of organic thin film transistors (OTFTs), the high operation voltage resulting from the low gate capacitance density of traditional SiO2 remains a severe limitation that hinders OTFTs’ development in practical applications
Our results demonstrate a simple and feasible route to fabricate high-performance OTFTs with solution-processed dielectric and low-cost electrode material, which is of great technical importance to realize large-scale application of organic electronics

Summary

Introduction

Rapid progress has been achieved in both the designing of novel organic semiconducting materials and the optimization of device fabrication techniques for organic thin film transistors (OTFTs) due to their potential applications in low-cost and flexible consumable electronics, such as such as RFID tags, flat panel displayers, and portable electronics [1,2,3,4]. The high operation voltage resulting from intrinsically low charge carrier mobility of organic semiconductors and the small gate capacitance density of traditional SiO2 remains a severe limitation that hinders their development in the market of commercial electronics [5]. This issue can be addressed through increasing the capacitance density of the gate dielectrics (Ci) by means of either increasing the dielectric constant (k) or decreasing the thickness (d) (Ci = 0k/d). It is of significant importance to develop a low-temperature, solution-based technique for the fabrication of high-k metal-oxides as gate dielectrics, in order to turn OTFTs into more reliable applications for low-cost, large-area devices

Methods

Results

Conclusion