Patterning and Encapsulation of Organic Optoelectronic Devices for Interfacing Neurons

In the last few years, organic optoelectronic devices, notably organic photodetectors (OPD) and organic light emitting diodes (OLED) have demonstrated exceptional performances in recording and stimulating neurons. Intrinsic properties of these polymers, electronic materials and devices, as well as their soft nature and mechanical conformability, make them excellent candidates for interacting with biological systems. Despite these important advancements, neuroscience applications of these devices are still limited due to important constraints of scalability and miniaturization technique. These challenges prevent these devices from efficiently interfacing with the brain for single cell recording and stimulation, due to low spatial resolution. Micro patterning and optimization of the optoelectronic properties of µ-scale OPD pixels will provide the advantage of optical recording from the brain at both cellular and population levels. Furthermore, a reliable mechanically-flexible encapsulation technology is essential to prevent the degradation of these devices while interfacing the brain. We have successfully patterned the active layer of OPDs and achieved miniaturized devices. Then, subsequently we studied the influence of micro-patterning on the fundamental physical properties of these devices. These OPDs are based on fullerene as acceptor and P3HT as donor. Different sizes of the active layer were patterned and encapsulated with a novel encapsulation approach. These miniaturization and encapsulation methods are also expandable to OLEDs.