Scientists Invent Electronic Circuits That Dissolve in Water
For most of us, an ideal electronic device is durable and long-lasting. An interdisciplinary team of researchers, though, has developed a new class of circuits that forces us to rethink our concept of what electronics can do in the world.
Their invention—an ultrathin, clear, silicon-based circuit that functions for a precise period of time, ranging from minutes to years, then dissolves completely in water—could lead to routine implantation of tiny electronics inside the body or in the environment without any need to extract them after use. The research team, from Tufts University, Northwestern University and the University of Illinois, reveals their advance in a paper published today in Science. They refer to it as an initial entry into a new field called “transient electronics.”
“These electronics are there when you need them, and after they’ve served their purpose they disappear,” said Yonggang Huang, who led the Northwestern portion of the team, which focused on theory, design and modeling. “This is a completely new concept.”
The circuits inside conventional electronics are made of silicon, a material that naturally dissolves in water over time but at rates that mean a typical circuit would take hundreds of years to disappear. The sheets of silicon that make up these new transient electronics, however, are just a few nanometers thick, so they can dissolve over the course of minutes when they come in contact with even a tiny volume of water or a body fluid. Watch how the circuit dissolves (almost like a breath-freshening strip) when it gets sprinkled with water, 15 seconds into this video: