Authors: J. Dong, B.A. Parviz, H.L. Yip, H. Ma and A.K-Y. Jen
Affilation: University of Washington, United States
Pages: 188 - 191
Keywords: self-assembly, self-assembled monolayers, charge transport, nano-channel
Molecular self-assembly can yield well-defined systems for charge carrier transport for the construction of a variety of devices such as field effect transistors and biosensors. We report a simple method to create an extremely confined charge carrier transport channel between two metal electrodes over a silicon dioxide surface using self-assembly of pyryl phosphonic acid (PYPA). The use of phosphonic acid group has allowed us to form the self-assembled monolayer (SAM), constituting the charge transport channel, on silicon dioxide. This ability provides the opportunity to integrate the channels with complementary metal oxide semiconductor integrated circuits in a one-step post-process procedure. We were able to create micron-domain sized multilayer crystals of PYPA between the electrodes by allowing self-assembly at room temperature and form a dense uniform 0.9 nm thin monolayer between the electrodes if the condensation reaction is allowed to proceed. We characterized the charge transport behavior of the multilayer nano-channels between the electrodes and observed an exponential dependence between the device current and the applied bias. We also studied the device current under constant biases when temperature was varied between 270°K and 310°K and observed a strong temperature dependence. These measurements indicate shallow trap dominated conduction behavior in the molecular system.