Nano@Illinois

Scientists break light modulation speed record - twice Milton Feng (left) and Nick Holonyak have constructed a light-emitting transistor that has set a new record with a signal-processing modulation speed of 4.3 gigahertz (Photo:  L. Brian Stauffer).

Aluminum-oxide nanopore beats other materials for DNA analysis Rashid Bashir (center), a Bliss Professor of electrical and computer engineering and of bioengineering, led the researchers who developed a new solid-state nanopore sensor. He is flanked by graduate students Murali Venkatesan (left) and Sukru Yemenicioglu. (Photo by L. Brian Stauffer)

Nanowires create smaller, faster transistors Electrical and computer engineering professor Xuling Li (right) and graduate research assistant Seth Fortuna have found a new way to make transistors smaller and faster. (Photo: L. Brian Stauffer)

New silver-based ink has applications in printed electronics Flexible silver microelectrodes printing on a polyimide substrate (Jennifer Lewis, et al., 2009, Illinois)

TEAM stage recognized in 2009 R&D 100 Awards TEAM nano-positioning stage for electron microscopy.

Scientists break light modulation speed record - twice

Researchers at the Illinois Micro and Nanotechnology   Laboratory, and the Center for Nanoscale Science and   Technology have constructed a light-emitting transistor  that has set a new record with a signal-processing  modulation speed of 4.3 gigahertz, breaking the previous  record of 1.7 gigahertz held by a light-emitting diode.   However, the researchers Nick Holonyak Jr., a John  Bardeen Chair Professor of Electrical and Computer Engineering and Physics, and Milton Feng, the Holonyak Chair Professor of Electrical and Computer Engineering at Illinois, and co-authors of recent papers on the new breakthrough, did not stop there. By internally connecting the base and collector of a light-emitting transistor, they created a new form of light-emitting diode, which modulates at up to 7 gigahertz, breaking the speed record once again. top

 

Aluminum-oxide nanopore beats other materials for DNA analysis

Fast and affordable genome sequencing has moved a step closer with a new solid-state nanopore sensor being developed by researchers at the University of Illinois.  The nanopore sensor, made by drilling a tiny hole through a thin film of aluminum oxide, could ultimately prove capable of performing DNA analysis with a single molecule, offering tremendous possibilities for personalized medicine and advanced diagnostics.

 

"Solid-state nanopore sensors have shown superior chemical, thermal and mechanical stability over their biological counterparts, and can be fabricated using conventional semiconductor processes," said ECE Professor Rashid Bashir.  "The aluminum-oxide nanopore sensors go a step further, exhibiting superior mechanical properties, enhanced noise performance and increased lifetime over their silicon-oxide and silicon-nitride counterparts," said Bashir, who is a Bliss Professor of Engineering and the director of the university's Micro and Nanotechnology Laboratory, and is affiliated with the University of Illinois Center for Nanoscale Science and Technology, Beckman Institute, FS Materials Research Laboratory, and the Institute for Genomic Biology. 

 

"The researchers describe the fabrication and operation of the aluminum-oxide nanopore sensor in a paper accepted for publication in Advanced Materials, and posted on the journal's Web site.  "More work must be done to achieve single base resolution, however," Bashir said. "Our next step is to detect and measure significantly shorter molecules." top

 

Nanowires create smaller, faster transistors

Researchers at the University of Illinois have found a new way to make transistors smaller and faster. The technique uses self-assembled, self-aligned, and defect-free nanowire channels made of gallium arsenide.

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In a paper in the IEEE (Institute of Electrical and Electronics Engineers) journal Electron Device Letters, U. of I. electrical and computer engineering professor Xiuling Li and graduate research assistant Seth Fortuna described the first metal-semiconductor field-effect transistor fabricated with a self-assembled, planar gallium-arsenide nanowire channel.

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Nanowires are attractive building blocks for both electronics and photonics applications. Compound semiconductor nanowires, such as gallium arsenide, are especially desirable because of their better transport properties and versatile heterojunctions. However, a number of challenges - including integration with existing microelectronics - must first be overcome.

 

""Our new planar growth process creates self-aligned, defect-free gallium-arsenide nanowires that could readily be scaled up for manufacturing purposes," said Li, who also is affiliated with the university's Micro and Nanoelectronics Laboratory and the Beckman Institute. "It's a non-lithographic process that can precisely control the nanowire dimension and orientation, yet is compatible with existing circuit design and fabrication technology." top

 

New silver-based ink has applications in printed electronics

A new ink developed by researchers at the University of Illinois allows them to write their own silver linings.

 

"The ink, composed of silver nanoparticles, can be used in electronic and optoelectronic applications to create flexible, stretchable and spanning microelectrodes that carry signals from one circuit element to another. The printed microelectrodes can withstand repeated bending and stretching with minimal change in their electrical properties.

 

"In a paper published by Science Express, the online version of the journal Science, Jennifer Lewis, the Thurnauer Professor of Materials Science and Engineering and director of the university's Frederick Seitz Materials Research Laboratory, and her collaborators demonstrate patterned silver microelectrodes by omnidirectional printing of concentrated nanoparticle inks with minimum widths of about 2 microns on semiconductor, plastic and glass substrates.

 

""Unlike inkjet or screen printing, our approach enables the microelectrodes to be printed out-of-plane, allowing them to directly cross pre-existing patterned features through the formation of spanning arches," Lewis said. "Typically, insulating layers or bypass electrode arrays are required in conventional layouts."

 

"Their approach consisted of creating highly integrated systems from diverse classes of electronic materials on a broad range of substrates.  Omnidirectional printing overcomes some of the design constraints that have limited the potential of printed electronics.

 

"In addition to Lewis, Ahn and Duoss, the paper's co-authors included chemistry professor Ralph Nuzzo and materials science and engineering professor John Rogers, as well as members of their research groups.   The work was funded by the U.S. Department of Energy. top

 

TEAM stage recognized in 2009 R&D 100 Awards

A novel nano-positioning stage for electron microscopy, co-invented by FSMRL staff members Eric Olson and Todor Donchev, and FSMRL Central Facilities Director Ivan Petrov, has been awarded a 2009 R&D 100 Award by R&D Magazine. The R&D 100 Awards are selected annually to recognize the most technologically significant new products or processes. The stage is used to hold and position samples inside electron microscopes with unprecedented stability, position-control accuracy, and range of motion. The invention is a collaboration between physicists, engineers, and designers from Lawrence Berkeley National Laboratory, the University of Illinois at Urbana-Champaign, Attocube Systems, and the FEI Company as part of the DOE-funded Transmission Electron Aberration-corrected Microscope (TEAM) project. top

 

NSF Renews NANO-CEMMS Center

"The Center for Nanoscale Chemical-Electrical-Mechanical Manufacturing Systems (Nano-CEMMS) at Illinois recently received a National Science Foundation $12.5 million grant renewal for an additional five years.   Since its inception Nano-CEMMS has been led by Placid Ferreira, Professor of Mechanical Science and Engineering. top

 

Illinois-Purdue Awarded I/UCRC Planning Grant

"Working jointly Illinois and Purdue faculty received an NSF planning grant for their Industry/University Collaborative Research Center proposed Center for Agricultural and Pharmaceutical Nanotechnology.  The proposed Center will be led by Brian Cunningham, Associate Professor, at ECE, Illinois, with Richard Linton, Food Science, at Purdue as the co-lead.  The inaugural workshop is scheduled for August 31-September 1, 2009 at the University of Illinois, to which industry, federal, state, and academic partners are invited.  www.cnst.illinois.edu/capn.htm top

 

Sources:  University of Illinois