A compact Spice model for organic TFTs and applications to logic circuit design

This work presents Spice implementation of a compact DC model developed for Organic Thin Film Transistors (OTFTs) that uses small molecules in binder matrix as active layer, and the simulation results of an inverter and a ring oscillator circuit which are built with this type of transistors. The DC model relies on a modified version of the Gradual Channel Approximation (GCA) that takes into account the contact effects occurring at non-ohmic metal/organic semiconductor junctions. The model also comprises channel length modulation and scalability of drain current with respect to channel length of the device. The experimental data of the fabricated device and Spice simulation results match well with each other. As an application example, an inverter and a ring oscillator circuit are simulated with Spice. Circuit simulation results show that it is possible to design further logic circuits using the presented model.