Methods of pentacene and related organic molecules for semiconductor applications

Emily Reith

Document Type Dissertation/Thesis

Abstract

This work explored the electronic properties of pentacene at the molecular level. Transistors made from thin films of pentacene have shown promise for large area electronic applications, such as liquid crystal displays. The mechanism for charge transport in pentacene, which is a p-type semiconductor, is not yet fully understood. Investigations into this question were carried out using AMI semi-empirical calculations, which included studies of electron density distributions of molecules and their radical cations. In these calculations, the geometry of one molecule of pentacene was first optimized. Next, a molecule of the radical cation of pentacene was placed at a set distance from the neutral molecule, and the dependence of the electronic delocalization on the dimer symmetry was calculated. In addition, charge transfer mechanisms were investigated between other molecules having different substituents at various positions on the pentacene rings. These systems may also exhibit favorable conductive properties.