An organic field effect transistor memory adopting octadecyltrichlorosilane self-assembled monolayer

Abstract

An organic nonvolatile memory is proposed based on octadecyltrichlorosilane self-assembled monolayer (ODTS SAM) and copper hexadecafluorophthalocyanine (F16CuPc) heterostructure, where F16CuPc acts as the active layer of the organic thin film transistor memory device, and ODTS SAM functions as the charge trapping layer. By adopting N-type active layer, sufficient electrons ensure the erasing process that is independent of the light illumination, indicating a fully electrically driving memory device, where large memory window is obtained. AFM images demonstrates that the monolayer provides the trapping sites. The trapping mechanism is analyzed based on the electric dipoles theory, the dipoles orientation in the monolayer is critical for providing trapping sites, which fixes the mobile carriers at the ODTS SAM/F16CuPc interface. The writing–reading–erasing–reading (WRER) tests and the retention time are shown, and they can be further optimized by involving a thin polystyrene tunneling layer between active layer and charge trapping layer, with an retention time of approximately 125 d, and a sufficient WRER reading current ratio of more than 103 for practical fully electrically driving binary nonvolatile memory device applications.