Constructing Gossamer Electronics

Ideal biocompatible electronics are like Olympic gymnasts: thin and flexible. That’s because devices with thin, flexible substrates can bend to the body’s curves, hugging organs and tissues in a way rigid devices cannot. Now, Giovanni A. Salvatore, Niko Münzenrieder, and coworkers at ETH Zurich have come up with a new way to make ultraflexible, lightweight, transparent electronics (Nat. Commun. 2014, DOI: 10.1038/ncomms3982). They construct the electronics on substrates made of a poly(p-xylylene) film just 1 μm thick and an underlayer of polyvinyl alcohol. After the fabrication is complete, the underlayer can be dissolved in water, leaving behind a gossamer device that still works when wrapped around a human hair. Because the poly(p-xylylene) is biocompatible, the thin electronics could be incorporated into biomedical devices. For example, the ETH team used the technique to create a thin-film transistor into which they incorporated a strain gauge. They then transferred the device to a contact lens. Such a sensor, they say, could be used to monitor intraocular pressure in glaucoma patient.