Organic Thin-Film Transistors Fabricated with Alignment-Free Printing Technique
- PDF / 534,718 Bytes
- 6 Pages / 595 x 842 pts (A4) Page_size
- 6 Downloads / 304 Views
I10.19.1
Organic Thin-Film Transistors Fabricated with Alignment-Free Printing Technique Masahiko Ando1, 2, Masahiro Kawasaki 1, 2, Shuji Imazeki 1, 2 1 Optoelectronic Industry and Technology Development Association (OITDA) 1-1, Higashi 1-Chome, Tsukuba-shi, Ibaraki-ken, 305-8565, Japan 2 Adavanced Research Laboratory, Hitachi, Ltd. 1-1, Omika-cho 7-chome, Hitachi-shi, Ibaraki-ken, 319-1292, Japan Hiroshi Sasaki Hitachi Research Laboratory, Hitachi, Ltd. 1-1, Omika-cho 7-chome, Hitachi-shi, Ibaraki-ken, 319-1292, Japan Toshihide Kamata National Institute of Advanced Industrial Science and Technology (AIST) 1-1, Higashi 1-Chome, Tsukuba-shi, Ibaraki-ken, 305-8565, Japan ABSTRACT A novel process for fabricating alignment-free, printable, organic thin-film transistors is presented. This process exploits a self-assembly phenomenon in which soluble nanomaterials such as metal nanoparticles and organic molecules are self-assembled into a device structure. To demonstrate this process, solution-processed source and drain electrodes were self-aligned to a gate electrode by using a hydrophobic self-assembled monolayer (SAM) optically patterned onto the gate electrode with a back-substrate exposure technique. An organic semiconductor film deposited on the patterned SAM was selectively ordered and substantially self-aligned to the gate electrode. A field-effect mobility of 0.15 cm2/Vs and on/off current ratio of 105 were experimentally demonstrated when pentacene molecules were used as the semiconductor and silver nanoparticles were used as electrode materials. INTRODUCTION The demand for low-cost, large-area arrays of thin-film transistors (TFTs) is increasing; these are needed to supply the huge number of electronic devices, such as electronic paper and IC tags, required for new forms of ubiquitous and mobile communication. Organic TFTs have potential for use as building blocks for electronic devices based on flexible substrates since they can be manufactured using inexpensive solution processing and direct printing processes rather than expensive vacuum deposition and photolithographic patterning [1]. Semiconductor organic molecules and polymers that are self-assembled from solutions into ordered structures have field-effect mobility comparable to that of inorganic films such as amorphous silicon. However, their practical application requires the development of novel printing techniques and device structures that provide accurate definition of device patterns with micrometer resolution but without highly complex processing. Alignment of the device components in a Thin Film Transistor (TFT) is one of the most important factors in the preparation of an organic high performance TFT. Especially, this is very serious problem in the preparation of an organic TFT on a flexible substrate when using a printing technique. The problem occurs because the flexible substrate often becomes deformed during device preparation and causes misalignment of the individual device components leading to degradation of TFT performance.
I10.19.2
I
Data Loading...
