Marina Feric
University:
Gradation Date: May 2010
Hometown:
My Project:
This summer I have been working on the organic electronics project that involves manipulating microstructure to achieve high performance Organic Thin Film Transistors (OTFTs). Organic electronics have great potential for applications in sensors, smart cards, RFID tags, and electronic paper. In particular, organic electronics can be processed at low costs and at low temperatures, resulting in their compatibility with flexible substrates. New and simple procedures are being investigated that allow relatively cheap processing while utilizing self-patterning and self-assembling molecules. Specifically, I have been investigating two similar organic molecules, tri-isopropylsilylethynyl perifluoropentacene (TIPS PFP) and tri-isopropylsilylethynyl catafluoropentacene (TIPS CFP), that solely differ in the position of the fluorine atom and that can be used as OTFTs. The chemical interactions associated with the organic molecules and with pentafluorobenzenethiol (PFBT), which was used for contact treatment, influence the crystallization, microstructure, and finally the overall electrical behavior of the OTFTs.
This work will be published as: High Performance Organic Thin-Film Transistors Made Simple Through Molecular Design and Processing, Oana D. Jurchescu, Marina Feric, Behrang H. Hamadani, Devin A. Mourey, Sankar Subramanian, Balaji Purushothaman, John E. Anthony, Thomas N. Jackson, and David J. Gundlach, in ECS Transactions - Honolulu, HI, Volume 13, "Thin Film Transistors 9 (
The treated devices of tri-isopropylsilylethynyl catafluoropentacene (TIPS CFP) show no crystallization or grain growth, which is reflected in the relatively low charge carrier mobilities. On the contrary, when the contacts are treated with pentafluorobenzenethiol (PFBT), then large crystalline grains grow from the contacts and into the channel. As seen in the schematic diagram, the PFBT treatment induces enhanced order of the organic molecules. As a result, the treated devices have much higher charge carrier mobilities. We observe that the high charge carrier mobilities, associated with the crystallization due to contact treatment, are a general feature that characterizes this class of organic molecules.
