The team first used standard clean-room techniques—including photolithography, metal sputtering, and atomic layer deposition—to create data storage circuits from zinc oxide, aluminum oxide, and silicon. Similar techniques yielded separate aluminum-based electronics to act as sensors for humidity or pressure. Making all these circuits microscopically thin ensured they would be flexible, but also fragile. To address this frailty, the team turned to a less mature technology. A commercial 3-D printer created flexible and custom-shaped polylactic acid enclosures to protect a sticker’s electronics. The researchers also “printed” additional wires to complete electrical connections with an ink-jet printer and a conductive silver ink.
by Matt Davenport |
October 18, 2016