Vapor Phase Deposition of Organic Semiconductors

The coming of age of organic circuits requires the development of high-performance and cost-effective processing techniques. In this work, the Organic Vapor Phase Deposition (OVPD™) is investigated for the production of thin semiconducting films used as the active layer of circuits. Two OVPD systems are described: A Static system that is inspired from a chemical vapor phase deposition tool and an In-line system that accommodates a linearly moving substrate and is roll-to-roll compatible. These two tools are tested for the growth of pentacene and PTCDI-C13, two high-mobility organic semiconductors. State of the art transistors and circuits on flexible substrates based on films of these materials are demonstrated. By means of transport and growth modeling supported by experimental results, it is shown how growth parameters can be optimized to lead to high material utilization efficiencies, to high thickness uniformities and to record film growth speeds. As a conclusion, this work shows that OVPD is a very promising candidate for the low-cost production of high-performance organic semiconducting thin films.