Reactive metal contact at indium–tin–oxide/self-assembled monolayer interfaces

With the aim of improving the electrical and adhesion properties of the indium–tin–oxide (ITO) electrode/organic interface, we tested Cl- and CF3-terminated self-assembled monolayers (SAMs), which react with the indium atoms of the electrode, and compared the results to those obtained using a CH3-terminated SAM. The contact resistance of the interface between the Cl-terminated surface and the ITO electrode (1.5kΩ) was found to be much lower than that of the interface between the ITO and the CF3-terminated surface (21.3kΩ), which can be attributed to the higher dipole moment of the In–Cl complex compared to the In–F complex. In the ITO films deposited on the CH3-terminated surface, the contact resistance (138.0kΩ) was much higher than those of the reactive metal contacts because the ITO thin film deposited on the CH3-terminated surface does not react with the SAM.