Three-dimensional rolled-up inductors have a footprint more than 100 times smaller without sacrificing performance. The researchers published their new design paradigm in the journal Nano Letters.
“It’s a new concept for old technology,” said team leader Xiuling Li, a professor of electrical and computer engineering at the University of Illinois.
Inductors, often seen as the sprawling metal spirals on computer chips, are essential components of integrated circuits. They store magnetic energy, acting as a buffer against changes in current and modulating frequency – especially important in radio-frequency wireless devices. However, they take up a lot of space. Inductance depends on the number of coils in the spiral, so engineers cannot make them smaller without losing performance.
In addition, the larger the area the inductor occupies, the more it interfaces with the substrate the chip is built on, exacerbating a hindering effect called parasitic capacitance. Researchers have developed some three-dimensional inductor structures to solve the dual problems of space and parasitic capacitance, but these methods are complex and use techniques that are difficult to scale up to manufacturing levels.
The new inductor design uses techniques Li’s group previously developed for making thin films of silicon nitrate, merely tens of nanometers in thickness, that roll themselves up into tubes. The research team used industry-standard two-dimensional processing to pattern metal lines on the film before rolling, creating a spiral inductor.
“We’re making 3-D structures with 2-D processing,” Li said. “Instead of spreading this out in a large area to increase inductance, we can have the same inductance but packed into a much smaller area.”
Using the self-rolling technique, the researchers can shrink the area needed for a radio-frequency inductor to a scant 45 microns by 16 microns – more than 100 times smaller than the area an equivalent flat spiral would require.
The design can be adjusted to fit target parameters including metal thickness and type, frequency, tube diameter and number of turns. According to Li, this technique could be used for capacitors and other integrated circuit elements as well.
Now, Li’s group is working to produce high-performance inductor prototypes, in collaboration with electrical and engineering professor Jose Schutt-Aine. Preliminary experimental data show strong correlation with the modeled designs.
“Once we have optimized this process, we should be able to make an integrated circuit with a completely different platform that could be much smaller,” Li said. “It’s an ambitious goal.”
The National Science Foundation and the Office of Naval Research supported this work. U. of I. visiting researcher Wen Huang, postdoctoral researcher Xin Yu, graduate student Paul Froeter and mechanical science and engineering professor Placid Ferreira were co-authors of this study. Li also is affiliated with the Beckman Institute for Advanced Science and Technology, the Micro and Nanotechnology Lab, and the Frederick Seitz Materials Research Lab, all at the U. of I.
Liz Ahlberg | Source: EurekAlert!
Further information: www.illinois.edu
Further Reports about: 2-D processing > 3-D structure > design paradigm > high-performance electronics > Illinois River Watershed > inductors > magnetic energy > parasitic capacitance > radio-frequency wireless devices > Science TV > specimen processing
More articles from Power and Electrical Engineering:
Successful start of the EU project SMARTIE: Security for Smart Cities
18.12.2013 | Leibniz-Institut für innovative Mikroelektronik GmbH
Offshore wind energy: Drilling instead of driving
18.12.2013 | Fachinformationszentrum Karlsruhe
A 12-year study of massive stars has reaffirmed that our Galaxy has four spiral arms, following years of debate sparked by images taken by NASA's Spitzer Space Telescope that only showed two arms.
The new research, which is published online today [17 December] in the Monthly Notices of the Royal Astronomical Society, is part of the RMS Survey, which was launched by academics at the University of Leeds.
Astronomers cannot see what our Galaxy, which is called the Milky Way, looks like because we ...
In collaboration with the University of Basel, an international team of researchers has observed a strong energy loss caused by frictional effects in the vicinity of charge density waves.
This may have practical significance in the control of nanoscale friction. The results have been published in the scientific journal Nature Materials.
Friction is often seen as an adverse phenomenon that leads to wear and causes energy loss. Conversely, however, too little friction can be a disadvantage as well – ...
A new type of transistor that could make possible fast and low-power computing devices for energy-constrained applications such as smart sensor networks, implantable medical electronics and ultra-mobile computing is feasible, according to Penn State researchers.
Called a near broken-gap tunnel field effect transistor (TFET), the new device uses the quantum mechanical tunneling of electrons through an ultrathin energy barrier to provide high current at low voltage.
Penn State, the National Institute of Standards and Technology and IQE, a specialty wafer manufacturer, jointly presented their findings at ...
The team of Johannes Zuber at the IMP in Vienna, Austria, managed to overcome remaining key limitations of RNA interference (RNAi) - a unique method to specifically shut off genes.
By using an optimized design, the scientists were able to inhibit genes with greatly enhanced efficiency and accuracy. The new method facilitates the search for drug targets and improves the interpretation of experimental results.
The IMP will make this „RNAi toolkit“ available to researchers. Results of the study are published in ...
Research The dangerous parasite Schistosoma mansoni that causes snail fever in humans could become significantly less common in the future a new international study led by researchers from the University of Copenhagen predicts.
The results are surprising because they contradict the general assumption that climate change leads to greater geographical spread of diseases. The explanation is that the parasite’s host snails stand to lose suitable habitat due to climate change.
“Our research shows that the expected effects of climate change will lead ...
18.12.2013 | Life Sciences
18.12.2013 | Medical Engineering
18.12.2013 | Studies and Analyses
11.12.2013 | Event News
10.12.2013 | Event News
05.12.2013 | Event News