Since the dawn of digital computing, innovators have been in search of greater computing power and efficiency. The ENIAC used nearly 18,000 vacuum tubes and could perform calculations in seconds that would have taken weeks by human effort. Transistors later reduced the size and cost of electronic devices. And the integrated circuit progressed from containing just a handful of transistors and logic gates to billions on one chip. But the next great leap in computing technology may be more about ubiquity than power.
The solution? Sensors, sensors everywhere! Professor Donald Lupo of the Tampere University of Technology (TUT) in Finland is working on ideas that will facilitate the development of the Internet of Things (IoT). Current production of silicon chips amounts to about 20 billion per year. But in anticipation of the requirement for trillions of sensors, Prof. Lupo and his colleagues are working on a broader concept. Their projects are focused on the Internet of Everything (IoE). (For more on IoT, see What are the Top Driving Forces for the Internet of Things (IoT)?)
I became fascinated with Prof. Lupo's work after reading an IEEE article for which he was interviewed. To meet the increasing requirements for connectivity on demand, Prof. Lupo and his teams are working to make low-cost, environmentally sustainable ubiquitous electronics possible. TUT, located in Finland's third-largest city, Tampere, is rated 11th in the world in terms of industry collaboration. Prof. Lupo is involved in two projects there in TUT's Laboratory of Future Electronics. I took advantage of my friendship with the multi-talented professor to ask him about them.
Prof. Lupo: “One is called Printed, energy Autonomous UniversaL (PAUL) platform for multifunctional wireless sensors and devices, which is a 5-year project funded by Tekes aiming at developing the technology to enable printing the Internet of Everything. The other one is a large Tekes-funded “Strategic Opening” called The Naked Approach, coordinated by VTT and with University of Oulu, Aalto University, Demos Helsinki and University of Lapland participating in addition to TUT. This project looks more globally at the vision of moving from a gadget-focused society to a gadget-free hyperconnected life, in which services appear as needed and disappear when no longer needed.”
Prof. Paul Berger of Ohio University has taken up a FiDiPro professorship at TUT. Professors Lupo and Berger as well as their team come from various backgrounds and fields to form a multi-disciplinary, international approach to technical innovation. The PAUL project has four objectives:
- Improved energy harvesting
- High-speed electronic devices
- Hybrid integration technology
- Full integration of roll-to-roll atomic layer deposition (ALD)
This is all about printed electronics. The Internet of Everything will use sensors anywhere and everywhere. I asked Prof. Lupo about the major obstacles to the integration of ALD and the mass production of high-speed electronic devices. (To learn more about IoT devices, see Are Wearable Devices a Threat to Corporate Networks?)
Prof. Lupo: “The obstacle for a long time was the fact that it was a very slow serial process where you needed to put down materials essentially an atomic layer at a time and pump out the reaction chamber each time. Recently leading ALD equipment manufacturers (e.g. Picosun and Beneq, both Finnish companies, but I think others are active too) have been developing continuous ALD machines and even roll-to-roll machines that can deposit onto flexible substrates. There is still work to be done in this area and we are actively pursuing the combination of ALD and printing, but for thin films (not more than a few tens of nanometers) I think it can be a good manufacturing solution.”
Prof. Lupo has heard rumors that ALD has already been in use in silicon chip production since 2007. But PAUL's printed electronics is something different. My next question: Is he proposing the end of silicon?
Prof. Lupo: “Absolutely not! Or at least not its replacement by printing. The density of devices you get on CMOS chips in computers is amazing and so is the speed. Printing will always have larger structures and therefore fewer chips. So the big data crunching (computers, servers) will probably be CMOS for a long time, and the replacement may be something completely different based on quantum phenomena. Printed electronics will open up areas for electronics and ubiquitous intelligence where silicon is already too powerful and overdimensioned.”
The second project in Prof. Lupo's portfolio works hand-in-hand with printed electronics. “The Naked Approach” makes use of sensors anywhere and everywhere the user goes. Imagine a digital world without gadgets. Whether at home, at work, at the mall, in a restaurant or even walking down the street, services materialize when needed, then disappear when the user is done with them. This YouTube video illustrates the concept. The Naked Approach website explains more. “Issues such as roaming, recognition, privacy and interfaces are looked at as well as so-called 'stick-it-on-devices,'” says Prof. Lupo.
Sensing some bewilderment in my questions, Professor Lupo kindly provided another summary of the technology:
Prof. Lupo: “The solution to enabling smart devices everywhere includes:
- Energy autonomy with non-toxic materials. This is the harvesting and storage part. It can also be applied to devices that include silicon chips, and in fact we expect this to come to market earlier than fully printed circuitry, probably in a few years.
- Printed, flexible, low-cost circuitry: this is the part about making printed electronics have good enough performance (speed, low energy, etc.) to be used in these ubiquitous devices. We think a combination of ALD and printing will be one way forward, but this is a longer term effort, where I expect proof of principle in the lab in coming years but a few more years before such things can be commercialized.”
This has the look of a breakthrough technology. Does he have any illusions that PAUL or The Naked Approach could represent an evolutionary step on the scale of the transistor or the integrated circuit?
Prof. Lupo: “Probably not in our groups alone, but if you consider the work that is being done in the world today, I think that the work that we and others are doing on energy autonomy and on silicon-free circuitry ('macroelectronics'?) could have a similar effect on our lives that the earlier development of microelectronics has had on our lives, by making the idea of 'Internet of Everything' or 'trillion sensors' feasible and ecologically sustainable.”
My initial approach was to probe Professor Lupo for a comparison to existing technologies. What is the future of printed electronics, and what will be its place in the market in the shadow of powerful silicon chip technology?
Prof. Lupo: “Printed electronics will probably never catch up with CMOS or a similar successor for high density, high-speed microprocessors and complex chips. But we believe that these ubiquitous sensors won’t need that level of processing capability, and that at this level (enough to do measurement of some simple parameters, do some data processing and communicate with a wireless node) printing can enable numbers of devices that aren’t really feasible with silicon. We also think that ALD will be a key part of this equation.”
So we all may look forward to a daily experience of the Internet of Everything that takes advantage of printed electronics and ubiquitous sensors. Everyone wants more connectivity. But Prof. Lupo spoke with excitement about potential uses for medical technology, such as wireless EKG sensors, remote telemetry of vital signs or a host of other diagnostic applications. A gadget-less future with a broad distribution of connectivity will doubtless characterize the exponential growth of the internet, and the evolution toward the Internet of Everything. Cheap, environmentally-friendly printed smart circuits may make all the difference.