Ultra-high gain diffusion-driven organic transistor

• Published in: Nature communications Vol. 7; no. 1; p. 10550
• Main Authors: Torricelli, Fabrizio, Colalongo, Luigi, Raiteri, Daniele, Kovács-Vajna, Zsolt Miklós, Cantatore, Eugenio
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.02.2016; Nature Publishing Group; Nature Portfolio
• Subjects: 639/301/119/995; 639/766/25; 639/925; Humanities and Social Sciences; multidisciplinary; Science; Science (multidisciplinary)
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms10550

Emerging large-area technologies based on organic transistors are enabling the fabrication of low-cost flexible circuits, smart sensors and biomedical devices. High-gain transistors are essential for the development of large-scale circuit integration, high-sensitivity sensors and signal amplification in sensing systems. Unfortunately, organic field-effect transistors show limited gain, usually of the order of tens, because of the large contact resistance and channel-length modulation. Here we show a new organic field-effect transistor architecture with a gain larger than 700. This is the highest gain ever reported for organic field-effect transistors. In the proposed organic field-effect transistor, the charge injection and extraction at the metal–semiconductor contacts are driven by the charge diffusion. The ideal conditions of ohmic contacts with negligible contact resistance and flat current saturation are demonstrated. The approach is general and can be extended to any thin-film technology opening unprecedented opportunities for the development of high-performance flexible electronics. Organic field-effect transistors offer limited gain due to the large contact resistance and the channel length modulation. Here, Torricelli et al. show a new transistor architecture where the charge injection and extraction are driven by the charge diffusion and a gain larger than 700 is achieved.