Some 2,000 years ago, the ancient Greeks built a comprehensive and wide-ranging library at Alexandria in Egypt. Its goal was to collect, in one location, no less than an archive of every written work then in existence. It's thought that, at its peak, the library was home to hundreds of thousands of scrolls and texts found throughout the breadth of the known world.
But data does nothing if not accumulate and that flood of data is piling up at a staggering rate. By the year 2000, scientists said the printed contents of the U.S. Library of Congress alone would have taken up 10 terabytes of memory, and that a petabyte of memory could store one copy of every bit of written information known to man.
It's thought that all the data currently stored in the world amounts to 1,200 exabytes, or a thousand petabytes. How much data is that? It's enough to cover the surface of the earth in a layer of printed books 50 deep.
In the era where Big Data has penetrated down to the small business level, how will all that information be stored?
A team of Taiwanese researchers say they've arrived at a process they use to 3D print a type of RRAM memory, and they do it on common printer paper. The idea is that computer memory could be printed locally with readily available materials to keep up with the staggering demand for storage we'll face in the future. The work was done at the Institute of Photonics and Optoelectronics at National Taiwan University and King Abdullah University of Science & Technology in Saudi Arabia.
The team says the memory is created by coating plain paper in layers of carbon, and then using titanium dioxide as ink, dots are printed to function as electrodes. Each bit of storage printed on paper is made up of an insulator between a pair of electrodes.
Using a sequence of inkjet and screen-printing techniques, the researchers made what they call a "simple metal–insulator–metal device structure" which can be used as a resistive random access memory device.
They say the results demonstrated reproducible switching endurance, reliable retention, a tunable memory window, and the capability to operate under extreme bending conditions.
And it's that ability to bend and retain its functional capabilities that the researchers say will prove invaluable. They foresee multifunctional, wearable, on-skin, and biocompatible applications.
And the construct has additional benefits as well; it's much less finicky when it comes to handling than a typical memory chip.
"The disposability and the high-security data storage of the paper-based memory are also demonstrated to show the ease of data handling, which are not achievable for regular silicon-based electronic devices. We envision that the PPMDs manufactured by this cost-effective and time-efficient all-printing approach would be a key electronic component to fully activate a paper-based circuit and can be directly implemented in medical biosensors, multifunctional devices, and self-powered systems."
Scientists Zhen-Kai Kao, Teng-Han Huang, Ying-Chih Liao, Der-Hsien Lien, Si-Chen Lee and Jr-Hau He say their results indicate that a single sheet of standard, 8.5" x 11" paper could hold up to 1MB of memory.
A visiting student at UC Berkeley, Lien says the method might ultimately be used to apply electronics to plastic foils as well as paper.
The individual dots which make up the memory matrix are just 50 microns in width and spaced 25 microns apart.