Memory device may archive data

Engineers at Princeton University and Hewlett-Packard have invented a combination of materials that could lead to cheap and super-compact electronic memory devices for archiving digital images or other data.

The invention could result in a single-use memory card that permanently stores data and is faster and easier to use than a compact disk.

The researchers achieved the result by discovering a previously unrecognised property of a commonly used conductive polymer plastic coating. Their memory device combines this polymer, which is inexpensive and easy to produce, with very thin film, silicon-based electronics.

The device would be like a CD in that writing data onto it makes permanent physical changes in the plastic and can be done only once. But it also would be like a conventional electronic memory chip because it would plug directly into an electronic circuit and would have no moving parts.

The discovery was made behind the device by experimenting with polymer material called PEDOT, which is clear and conducts electricity. It has been used for years as an anti-static coating on photographic film and more recently as an electrical contact on video displays that require light to pass through the circuitry.

It was found that PEDOT conducts electricity at low voltages but permanently loses its conductivity when exposed to higher voltages (and thus higher currents), making it act like a fuse or circuit breaker.