The lab of Rice University chemist James Tour has developed transparent, flexible memories using silicon oxide as the active component. Tour revealed today in a talk at the national meeting and exposition of the American Chemical Society in San Diego that the new type of memory could combine with the likes of transparent electrodes developed at Rice for flexible touchscreens and transparent integrated circuits and batteries developed at other labs in recent years.
Rice’s transparent memory is based upon the 2010 discovery that pushing a strong charge through standard silicon oxide, an insulator widely used in electronics, forms channels of pure silicon crystals less than 5 nanometers wide. The initial voltage appears to strip oxygen atoms from the silicon oxide; lesser charges then repeatedly break and reconnect the circuit and turn it into nonvolatile memory. A smaller signal can be used to poll the memory state without altering it. That discovery was reported on the front page of the New York Times. The Rice lab has since developed a working two-terminal memory device that can be stacked in a three-dimensional configuration and attached to a flexible substrate.