TORONTO--There's a lot of talk about developing small, low-power memories for connected devices for the rapidly growing Internet of Things (IoT) market. But there are opportunities for memory where devices need not be connected, and that's where printed memory can play a role.
Thin Film Electronics ASA (ThinFilm) is one company that has a developed printed electronics and smart systems, including memory, which was recently demonstrated at Drupa, the world's largest printing equipment exhibition, by Xerox. It licensed the technology in January 2015 and is modifying a production line in one of its existing facilities in Webster, N.Y., to produce the memory labels.
In a telephone interview with EE Times, Xerox Printed Memory Marketing Manager Patrick de Jong said its printed memory can add low-cost intelligence to objects or packaging by printing thin circuitry on a substrate such as a plastic label.
“It's flexible, so it fits into many types of applications," de Jong said. The thin, non-volatile memory labels can be placed on products at any stage of the manufacturing or supply-chain process and can store up to 36 bits of information. That doesn't seem like a lot, but it actually enables 68 billion distinct data combinations.
Unlike IoT devices, which by definition are connected to a network, data on Xerox Printed Memory is written and read offline, and a reader needs to make physical contact. This eliminates interference and enhances security. Data retention is up to 10 years, de Jong said, and everything from lot codes and serial numbers to expiration dates and geographic IDs can be stored on the labels.
Data stored on the printed memory might be about product itself or the customer, de Jong said. And despite the small capacity of the memory, the data can be significant, he added. Applications include smart consumables to provide authentication and intelligence for prescription refills, for example, or any dispensing device, including coffee machines.
Printed memory can also be used for brand protection, and not just because counterfeiting can cost companies billions to trillions of dollars in damage, but also for safety. Fighting counterfeit pharmaceuticals in third-world countries is a matter of life or death.
“In the pharmaceutical industry security is everything because they play with people's lives," de Jong said. “You could be swallowing washing powder instead of the drug you are being supplied with."
The printed memory was invented by ThinFilm with help from collaborator Xerox PARC, which came up with the cryptographic capabilities, combined with tried and true bar code technology. Memory and unique code are printed on the substrate, with encryption enabled by a unique printed code, such as QR code, in combination with the printed memory. Data can be written and read offline using an inexpensive contact reader that interfaces with an existing smartphone.
Memory and unique code are printed on the substrate, with encryption enabled by a unique printed code, such as QR code, in combination with the Xerox printed memory.
De Jong said Xerox Printed Memory does not want to supplant existing technology but aims to enhance what is already on the market by striking a balance between cost and security.
“RFID is contactless but it has limitations," he said. “It's expensive compared to printed memory and for smart consumables it's prohibitive."
ThinFilm's printed memory is not the only option on the market, said Jim Handy, principal analyst with Objective Analysis. The company's strengths has been that it can make printed electronics at a low cost, and it had the complete breadth of a solution--not just memory, but the logic elements, liquid crystal display technology and battery.
To be viable, Handy said, printed memory needs to be cheap. While 3D printing is a cheap way to produce a custom-made item, it doesn't make sense for mass production. He equated it to CNC tooling, which goes back several decades.
Printed memory does make sense for certain uses cases, he said, citing the ability to authenticate a product, particularly valuable items--truffles, for example--that come in limited quantities. It would provide a method of verifying the product and even the specific farm those truffles came from.
Similar to EEPROM, said Handy, which stores 256 bits and is the cheapest thing you can put on a board, printed memory makes sense for “small data." But it you calculated the dollars per gigabyte, the cost would be astronomical compared to NAND flash.
Printed memory has a long history. For example, research on paper electronics goes back as far as the 1960s, when a group at Westinghouse experimented with paper as a substrate for thin-film transistors that could be built into switching arrays to control individual pixels in a liquid-crystal display.
Research has shown that so-called printed-paper-based memory devices (PPMDs) exhibit reproducible switching endurance, reliable retention, a tunable memory window, and the capability to operate under extreme bending conditions. A PPMD can be used as a labeled on electronics or living things for multifunctional, wearable, on-skin, and biocompatible applications. PPMDs could be directly implemented in medical biosensors, multifunctional devices, and self-powered systems.
—Gary Hilson is a general contributing editor with a focus on memory and flash technologies for EE Times.