Contactless Droplet Manipulation for Highly Aligned Organic Semiconductors

The introduction of innovative manufacturing techniques is steadily revolutionising the way we live in the UK and globally. Specifically, the possibility of printing materials and devices (including flexible printed electronics) herald a new era with unparalleled solutions to tackle many global economic and societal challenges, such as personalised healthcare, energy harvesting, information processing and sustainability. Organic semiconductors are a class of lightweight and flexible organic molecules with unprecedented potential for printing electronic devices, such as wearable sensors for personalised health monitoring. The electronic performance of thin films of these molecules critically depends on the degree of their molecular alignment in the deposited patterns. Nonetheless, current printing techniques (e.g., inkjet printing) are limited in the level of alignment that can be realistically achieved while patterning OSC films, thus ultimately hindering the integration of organic semiconductors in devices. In this project, we propose to develop a novel non-contact printing technique capable of improving molecular alignment in thin polymer films and, thus, of boosting the electronic performance of printed organic semiconducting films. Our approach will be based on the contactless transport of tiny droplets containing dissolved organic semiconductor molecules. While moving, these droplets can deposit material on a substrate with a preferential direction, thus enhancing processes of molecular alignment and self-assembly. We envisage that our novel approach to printing organic semiconductors will not only generate fundamental understanding about phenomena of molecular deposition, alignment and self-assembly, but it will also enable us to improve the performance of flexible printed electronics for the development of flexible electronic devices based on organic semiconductors.