Abstract: We investigated the electrical stabilities of two types of pentacene-based organic thin-film transistors (OTFTs) with two different polymeric dielectrics: polystyrene (PS) and poly(4-vinyl phenol) (PVP), in terms of the interfacial charge depletion. Under a short-term bias stress condition, the OTFT with the PVP layer showed a substantial increase in the drain current and a positive shift of the threshold voltage, while the PS layer case exhibited no change. Furthermore, a significant increase in the off-state current was observed in the OTFT with the PVP layer which has a hydroxyl group. In the presence of the interfacial hydroxyl group in PVP, the holes are not fully depleted during repetitive operation of the OTFT with the PVP layer and a large positive gate voltage in the off-state regime is needed to effectively refresh the electrical characteristics. It is suggested that the depletion-limited holes at the interface, i.e., interfacial charge depletion, between the PVP layer and the pentacene layer play a critical role on the electrical stability during operation of the OTFT.
This is an open access article distributed under the
Creative Commons Attribution License which permits unrestricted use, distribution,
and reproduction in any medium, provided the original work is properly cited.
Export to BibTeX
MDPI and ACS Style
Park, J.; Bae, J.-H.; Kim, W.-H.; Kim, M.-H.; Keum, C.-M.; Lee, S.-D.; Choi, J.S. Effects of Interfacial Charge Depletion in Organic Thin-Film Transistors with Polymeric Dielectrics on Electrical Stability. Materials 2010, 3, 3614-3624.
Park J, Bae J-H, Kim W-H, Kim M-H, Keum C-M, Lee S-D, Choi JS. Effects of Interfacial Charge Depletion in Organic Thin-Film Transistors with Polymeric Dielectrics on Electrical Stability. Materials. 2010; 3(6):3614-3624.
Park, Jaehoon; Bae, Jin-Hyuk; Kim, Won-Ho; Kim, Min-Hoi; Keum, Chang-Min; Lee, Sin-Doo; Choi, Jong Sun. 2010. "Effects of Interfacial Charge Depletion in Organic Thin-Film Transistors with Polymeric Dielectrics on Electrical Stability." Materials 3, no. 6: 3614-3624.