SAN FRANCISCO Ambient intelligence is the next wave of information technology, driven by software and both enabled and constrained by nanoscale physics, according to a researcher speaking at the International Solid State Circuits Conference here.
Hugo De Man, senior research fellow at the Interuniversity Microelectronics Center (IMEC, Leuven, Belgium), said the emergence of ambient intelligence will not require devices based solely on CMOS technologies. Instead, technologies emerging around CMOS, such as 3D packaging, microelectromechanical systems (MEMS) and polymer displays will also play key roles. Nanoscale biosensors could also connect electronics to biotechnology via IPv6, the next generation Internet protocol that enables every object on earth to have its own unique IP address.
In his ISSCC keynote address, De Man said Moore's Law scaling can only go so far. He called for a "more-than-Moore" strategy, the cost-effective integration of CMOS with MEMS, optical and passive components, new materials, biosilicon interfaces, autonomous energy sources and grain-size 3D packaging.
Complexity rests not in the number of transistors but in combining technologies with networking architectures to obtain simple sensor nodes. These microwatt devices are low-duty-cycle, low-throughput microsystems that unify a design into a single package: sensor, signal conditioning, A/D conversion, signal processing, a power-aware MAC layer, antennas, energy management and energy scavenging.
IMEC has developed a 1.4-cm3 2.4GHz sensor based on laminate packaging of bare dies, a
solar-cell battery charger and an integrated antenna, De Man said. The system consumes 500 microwatts at 400 bits/s and has a 1 percent duty cycle. For true energy scavenging, only solar cells, piezoelectric MEMS and thermal generators have proven successful, but their average power capacity is limited to 100 microWatts/cm3.
Massive sensor deployment will require cost reductions down to the single-cent range. That not a problem with standard CMOS, but will be with non-CMOS devices such as passive components and MEMS.
The goal is to move ambient intelligence from the laboratory into the market. Ambient intelligence seeks to surround the environment with enabling technologies in a nonintrusive way by conspicuously hiding the technology behind its own "intelligence."
Healthcare could be an important application for ambient intelligence, providing the interface between electronics and biotissues. Other progress in this area was reported at the ISSCC.
Peter Fromherz at the Max Planck Institute for Biochemistry (Munich, Germany) is attempting to use neural circuits for technological applications. Since computers and the human brain use different charge carriers, the challenge for neuroelectronics is finding interfaces that are noninvasive for cells and noncorrosive for chips.
Meanwhile, a hybrid IC/microfluidic system developed at Harvard Univeristy's medical school could provide precise spatial control of individual biological cells using programmable magnetic fields. The system IC was made with SiGe, but it can be fabricated using CMOS technology, according the research team. A full CMOS/microfluidic hybrid system could serve as a single-use disposable device for performing biological experiments.
The IC produces spatially patterned magnetic fields created by an integrated microelectromagnet array. The magnetic fields can manipulate individual cells that are tagged by magnetic beads suspended in the microfluidic system.
De Man said IMEC is collaborating with Philips and Bosch on developing a technique to make integrated poly-SiGe gyroscopes. The fabrication technique is based on larger CMOS wafers and uses three extra mask steps. The 0.35-micron CMOS process includes five metal layers and standard passivation.
The process has the potential to become a generic technology in which different MEMS devices such as resonators and accelerometers can be processed together on top of standard CMOS, De Man said.