June 8, 2019
- A team of researchers in the group of Professor Russell Holmes has recently reported a novel phenomenon in which micron-scale, aligned, periodic patterns can be realized in organic semiconductor thin films during crystallization. The team consisted of current graduate students John Suddard-Bangsund, Kaicheng Shi, and Catherine Clark, former graduate student Tom Fielitz, and undergraduate students Trevor Steiner and Jack Van Sambeek. The team found that when initially glassy thin films were annealed under certain conditions, the resulting crystallization yielded a periodic film topography. Patterning extends through almost the full thickness of the film and its period can be tuned with thickness over a range of 800 nm to 2400 nm. This phenomenon presents a promising method for direct patterning of organic semiconductor thin films, which is generally challenging due to their incompatibility with conventional photolithography. The ability to realize patterns by self-assembly at optically-relevant length-scales is expected to have application for light management in organic light-emitting devices (OLEDs), solar cells, and other photonic devices.
Related Link: https://doi.org/10.1038/s41563-019-0379-3