The day is not far when electronic memory chips would gain the ability to be bended and twisted, for engineers at the National Institute of Standards and Technology (NIST) have found a way to build a flexible memory component out of inexpensive, readily available materials.
Although the new device is not ready to debut in the market, but it holds promise not only because of its potential applications in medicine and other fields, but also because it has the characteristics of a memristor. A memristor is a fundamentally new component for electronic circuits that industry scientists developed in 2008.
Scientists seek electronic components that can flex without breaking for many reasons-for example they could be worn on the skin to monitor heart rate or blood sugar. Although there exist some flexible components, the NIST researchers think that creating flexible memory is a technical barrier.
Thus, while hunting for a solution, the researchers took polymer sheets-the sort that transparencies for overhead projectors are made from-and experimented with depositing a thin film of titanium dioxide, an ingredient in sunscreen, on their surfaces.
They deposited the material by a sol gel process, which consists of spinning the material in liquid form and letting it set, like making gelatin.
They added electrical contacts and created a flexible memory switch that operates on less than 10 volts, maintains its memory when power is lost, and still functions after being flexed more than 4,000 times.
In fact, the switch's performance strongly resembles to that of a memristor-a component theorised in 1971 as a fourth fundamental circuit element (along with the capacitor, resistor and inductor).
A memristor is essentially a resistor that changes its resistance depending on the amount of current that is sent through it-and retains this resistance even after the power is turned off.
The NIST component demonstrates similar electrical behaviour like a memristor, and is also flexible. And, thus, they can begin to explore the metrology that may be necessary to study the device's unique electrical behaviour.
"We wanted to make a flexible memory component that would advance the development and metrology of flexible electronics, while being economical enough for widespread use. Because the active component of our device can be fabricated from a liquid, there is the potential that in the future we can print the entire memory device as simply and inexpensively as we now print a slide on an overhead transparency," said NIST researcher Nadine Gergel-Hackett.