Boundary research between organic conductors and transistors: new trends for functional molecular crystals

In organic transistors, the contact resistance at the interface between the organic semiconductor (OSC) and electrode reduces the device performance. To solve this problem, a buffer layer is inserted between the electrode and OSC layer to decrease the depletion layer that forms at the OSC surface. Especially in bottom-contact transistors, the effects of interfacial potentials and carrier traps can be suppressed using high-conductivity organic-conductors and carbon pastes as electrodes. Accordingly, a "self-contact" transistor was proposed based on chemically doping OSCs. This technique enables us to fabricate organic conductor electrodes specific to each OSC, resulting in transistors with low contact resistance. However, organic conductors based on OSCs are essential to expand the fabrication of these devices using the doping method. Consequently, OSCs have been used to develop a promising new class of organic conductors with high conductivity and excellent thermoelectric properties. Although developing organic conductors based on OSCs remains relatively unexplored, it is expected to become a new trend in functional molecular compounds.