Imec gears up for the Internet of Things economy
It is the imec's CEO's first trip to Israel and around us the room is being prepared for an afternoon of presentations the Belgium nanoelectronics research centre will give on its work in such areas as the Internet of Things and 5G wireless to an audience of Israeli start-ups and entrepreneurs.
Luc Van den hove
iMinds merger
Imec announced in February its plan to merge with iMinds, a Belgium research centre specialising in systems software and security, a move that will add 1,000 staff to imec's 2,500 researchers.
At first glance, the world-renown semiconductor process technology R&D centre joining forces with a systems house is a surprising move. But for Van den hove, it is a natural development as the company continues to grow from its technology origins to include systems-based research.
"Over the last 15 years we have built up more activities at the system level," he says. "These include everything related to the Internet of Things - our wireless and sensor programmes; we have a very strong programme on biomedical applications, which we sometimes refer to as the Internet of Healthy Things - wearable and diagnostics devices, but always leveraging our core competency in process technology."
Imec is also active in energy research: solar cells, power devices and now battery technology.
For many of these systems R&D programmes, an increasing challenge is managing data. "If we think about wearable devices, they collect data all the time, so we need to build up expertise in data fusion and data science topics," says Van den hove. There is also the issue of data security, especially regarding personal medical data. Many security solutions are embedded in software, says Van den hove, but hardware also plays a role.
Imec expects the Internet of Things to generate massive amounts of data, and more and more intelligence will need to be embedded at different levels in the network
"It just so happens that next to imec we have iMinds, a research centre that has top expertise in these areas [data and security]," says Van den hove. "Rather than compete with them, we felt it made more sense to just merge."
The merger also reflects the emergence of the Internet of Things economy, he says, where not only will there be software development but also hardware innovation: "You need much more hardware-software co-development". The merger is expected to be completed in the summer.
Internet of Things
Imec expects the Internet of Things to generate massive amounts of data, and more and more intelligence will need to be embedded at different levels in the network.
"Some people refer to it as the fog - you have the cloud and then the fog, which brings more data processing into the lower parts of the network," says Van den hove. "We refer to it as the Intuitive Internet of Things with intelligence being built into the sensor nodes, and these nodes will understand what the user needs; it is more than just measuring and sending everything to the cloud."
Van den hove says some in the industry believe that these sensors will be made in cheap, older-generation chip technologies and that processing will be performed in data centres. "We don't think so," he says. "And as we build in more intelligence, the sensors will need more sophisticated semiconductors."
Imec's belief is that the Internet of Things will be a driver for the full spectrum of semiconductor technologies. "This includes the high-end [process] nodes, not only for servers but for sophisticated sensors," he says.
"In the previous waves of innovation, you had the big companies dominating everything," he says. "With the Internet of Things, we are going to address so many different markets - all the industrial sectors will get innovation from the Internet of Things." There will be opportunities for the big players but there will also be many niche markets addressed by start-ups and small to medium enterprises.
Imec's trip to Israel is in response to the country's many start-ups and its entrepreneurship. "Especially now with our wish to be more active in the Internet of Things, we are going to work more with start-ups and support them," he says. "I believe Israel is an extremely interesting area for us in the broad scope of the Internet of Things: in wireless and all these new applications."
Herzliya
Semiconductor roadmap
Van den hove's background is in semiconductor process technology. He highlights the consolidation going on in the chip industry due, in part, to the CMOS feature nodes becoming more complex and requiring greater R&D expenditure to develop, but this is a story he has heard throughout his career.
"It always becomes more difficult - that is Moore's law - and [chip] volumes compensate for those challenges," says Van den hove. When he started his career 30 years ago the outlook was that Moore's law would end in 10 years' time. "If I talk to my core CMOS experts, the outlook is still 10 years," he says.
Imec is working on 7nm, 5nm and 3nm feature-size CMOS process technologies. "We see a clear roadmap to get there," he says. He expects the third dimension and stacking will be used more extensively, but he does not foresee the need for new materials like graphene or carbon nanotubes being used for the 3nm process node.
Imec is pursuing finFET transistor technology and this could be turned 90 degrees to become a vertical nanowire, he says. "But this is going to be based on silicon and maybe some compound semiconductors like germanium and III-V materials added on top of silicon." The imec CEO believes carbon-based materials will appear only after 3nm.
"The one thing that has to happen is that we have a cost-effective lithography technique and so EUV [extreme ultraviolet lithography] needs to make progress," he says. Here too he is upbeat pointing to the significant progress made in this area in the last year. "I think we are now very close to real introduction and manufacturing," he says.
We see strong [silicon photonics] opportunities for optical interconnect and that is one of our biggest activities, but also sensor technology, particularly in the medical domain
Silicon Photonics
Silicon photonics is another active research area with some 200 staff at imec and at its associated laboratory at Ghent university. "We see strong opportunities for optical interconnect and that is one of our biggest activities, but also sensor technology, particularly in the medical domain," he says.
Imec views silicon photonics as an evolutionary technology. "Photonics is being used at a certain level of a system now and, step by step, it will get closer to the chip," he says. "We are focussing more on when it will be on the board and on the chip."
Van den hove talks about integrating the photonics on a silicon interposer platform to create a cost-effective solution for the printed circuit board and chip levels. For him, first applications of such technology will be at the highest-end technologies of the data centre.
For biomedical sensors, silicon photonics is a very good detector technology. "You can grow molecules on top of the photonic components and by shining light through them you can perform spectroscopy; the solution is extremely sensitive and we are using it for many biomedical applications," he says.
Looking forward, what most excites Van den hove is the opportunity semiconductor technology has to bring innovation to so many industrial sectors: "Semiconductors have created a fantastic revolution is the way we communicate and compute but now we have an opportunity to bring innovation to nearly all segments of industry".
He cites medical applications as one example. "We all know people that have suffered from cancer in our family, if we can make a device that would detect cancer at a very early stage, it would have an enormous impact on our lives."
Van den hove says that while semiconductors is a mature technology, what is happening now is that semiconductors will miniaturise some of the diagnostics devices just like has happened with the cellular phone.
"We are developing a single chip that will allow us to do a full blood analysis in 10 minutes," he says. DNA sequencing will also become a routine procedure when visiting a doctor. "That is all going to be enabled by semiconductor technology."
Such developments is also a reflection of how various technologies are coming together: the combination of photonics with semiconductors, and the computing now available.
Imec is developing a disposable chip designed to find tumour cells in the blood that requires the analysis of thousands of images per second. "The chip is disposable but the calculations will be done on a computer, but it is only with the most advanced technology that you can do that," says Van den hove.
Start-up Sicoya targets chip-to-chip interfaces
“The trend we are seeing is the optics moving very close to the processor,” says Sven Otte, Sicoya’s CEO.
Sicoya was founded last year and raised €3.5 million ($3.9 million) towards the end of 2015. Many of the company’s dozen staff previously worked at the Technical University of Berlin. Sicoya expects to grow the company’s staff to 20 by the year end.
Otte says a general goal shared by silicon photonics developers is to combine the optics with the processor but that the industry is not there yet. “Both are different chip technologies and they are not necessarily compatible,” he says. “Instead we want the ASPIC very close to the processor or even co-packaged in a system-in-package design.”
Vertical-cavity surface-emitting lasers (VCSELs) are used for embedded optics placed alongside chips. VCSELs are inexpensive to make, says Otte, but they need to be packaged with driver chips. A VCSEL also needs to be efficiently coupled to the fibre which also requires separate lenses. ”These are hand-made transceivers with someone using a microscope to assemble,” says Otte. “But this is not scalable if you are talking about hundreds of thousands or millions of parts.”
He cites the huge numbers of Intel processors used in servers. “If you want to put an optical transceiver next to each of those processors, imagine doing that with manual assembly,” says Otte. “It just does not work; not if you want to hit the price points.”
In contrast, using silicon photonics requires two separate chips. The photonics is made using an older CMOS process with 130nm or 90nm feature sizes due to the relatively large dimensions of the optical functions, while a more advanced CMOS process is used to implement the electronics - the control loops, high-speed drivers and the amplifiers - associated with the optical transceiver. If an advanced CMOS process is used to implement both the electronics and optics on the one chip, the photonics dominates the chip area.
“If you use a sophisticated CMOS process then you pay all the money for the electronics but you are really using it for the optics,” says Otte. “This is why recently the two have been split: a sophisticated CMOS process for the electronics and a legacy, older process for the optics.”
Sicoya is adopting a single-chip approach, using a 130nm silicon germanium BiCMOS process technology for the electronics and photonics, due to its tiny silicon photonics modulator. “Really it is an electronics chip with a little bit of optics,” says Otte.
You can’t make a data centre ten times larger, and data centres can’t become ten times more expensive. You need to do something new.
Modulation
The start-up does not use a traditional Mach-Zehnder modulator or the much smaller ring-resonator modulator. The basic concept of the ring resonator is that by varying the refractive index of the ring waveguide, it can build up a large intensity of light, starving light in an adjacent coupled waveguide. This blocking and passing of light is what is needed for modulation.
The size of the ring resonator is a big plus but its operation is highly temperature dependent. “One of its issues is temperature control,” says Otte. “Each degree change impacts the resonant frequency [of the modulator].” Moreover, the smaller the ring-resonator design, the more sensitive it becomes. “You may shrink the device but then you need to add a lot more [controlling] circuitry,” he says.
Stefan Meister, Sicoya’s CTO, explains that there needs to be a diode with a ring resonator to change the refractive index to perform the modulation. The diode must be efficient otherwise, the resonance region is narrow and hence more sensitive to temperature change.
Sicoya has developed its own modulator which it refers to as a node-matched diode modulator. The modulator uses a photonic crystal; a device with a periodic structure which blocks certain frequencies of light. Sicoya’s modulator acts like a Fabry-Perot resonator and uses an inverse spectrum approach. “It has a really efficient diode inside so that the Q factor of the resonator can be really low,” says Meister. “So the issue of temperature is much more relaxed.” The Q factor refers to the narrowness of the resonance region.
Operating based on the inverse spectrum also results in Sicoya’s modulator having a much lower loss, says Meister.
Sicoya is working with the German foundry IHP to develop its technology and claims its modulator has been demonstrated operating at 25 gigabit and at 50 gigabit. But the start-up is not yet ready to detail its ASPIC designs nor when it expects to launch its first product.
5G wireless
However the CEO believes such technology will be needed with the advent of 5G wireless. The 10x increase in broadband bandwidth that the 5G cellular standard promises coupled with the continual growth of mobile subscribers globally will hugely impact data centres.
“You can’t make a data centre ten times larger, and data centres can’t become ten times more expensive, says Otte. “You need to do something new.”
This is where Sicoya believes its ASPICs can play a role.
“You can forward or process ten times the data and you are not paying more for it,” says Otte. “The transceiver chip is not really more expensive than the driver chip.”