Material Selection for Biodegradable Organic Thin Film Transistors

Biodegradable organic thin film devices allow flexible electronics devices which decompose after an intended period of operation. Examples are devices that can be recycled by industrial composting facilities or medical implants which are absorbed by the living organism. In literature, the feasibility of thin film transistor (TFT) structures based on various nature-inspired or biodegradable materials has been demonstrated (e.g. [1, 2]). The focus of our work was on biodegradable conductive traces on PLA substrates and TFT using hybrid polymers and now we employ gelatin as gate-insulator and potential substrate. Gelatin as a common food component is a particularly interesting material which has already been investigated as gate dielectric for TFT [3]. As top contacts, we use MoO3/Mg structures and as semiconductor quinacridone. The vacuum deposition of biodegradable conductive tracks on a biodegradable substrate such as PLA is not strait forward due to extremely poor sticking, but can be solved by suitable pre-treatment or interlayers. In this way, we expect that all materials used are suitable for potential application in compostable/bioresorbable devices.