Nanotechnology switches back to vacuum transistors at low voltage
July 03, 2012 // Peter Clarke
Researchers at the University of Pittsburgh have come up with a device structure that allows a switch back to vacuum, in contrast to the solid-state, as the medium for electron transport in transistors.
The team is proposing a MOS vertical structure with a triple layer of metal/silicon dioxide/silicon exposed on the side by a deep trench. The metal and silicon layers form the anode and cathode of the device, separated by the insulating silicon dioxide, and the electron transport occurs in the vertical direction through the vacuum.
The work is discussed in a research paper entitled Metal-oxide-semiconductor field effect transistor with a vacuum channel, published in Nature Nanotechnology July 1.
The work represents a return to the roots of electronics. The solid-state transistor was invented in 1947 as a replacement for the bulky, unreliable vacuum tube. Vacuum tube style electronics in miniature made using solid-state semiconductor manufacturing techniques have been tried before, but the concept has struggled to overcome requirements for high voltage and issue of compatibility with the incumbent solid-state CMOS technology.
A team under Hong Koo Kim, principal investigator on the project and a Professor in the University of Pittsburgh's Swanson School of Engineering, has redesigned the structure of the vacuum electronic device. With the assistance of PhD candidate Siwapon Srisonphan and postdoctoral fellow Yun Suk Jung Kim and his team discovered that electrons trapped inside a semiconductor at the interface with an oxide or metal layer can be easily extracted out into the air. The electrons at the material interface form a sheet of charges, a two-dimensional electron gas and Kim found that the Coulombic repulsion of the electrons for each other enables the easy emission of electrons out of the silicon.
This allows the creation of a low-voltage device in which the electrons travel ballistically in air in a nanometer-scale channel without any collisions or scattering.
The channel length is of the order of 20-nm and the team measured a transconductance of 20-nS per micron and an on/off ratio of 500 and turn-on gate voltage of 0.5-V under ambient conditions, according to the paper's abstract.
"The emission of this electron system into vacuum channels could enable a new class of low-power, high-speed transistors, and it's also compatible with current silicon electronics, complementing those electronics by adding new functions that are faster and more energy efficient due to the low voltage," said Professor Kim, in a statement.
Nature Nanotechnology article
Trinamic's stepper motor package gets you started
August 29, 2014
This month, Trinamic Motion Control is offering you to win one of four TMCM-1043 development kits for its highly integrated, ...
Winged parcel delivery: Google's way
Two-inch Super AMOLED display fits Samsung smartwatch plans
Dutch startup shrinks 60GHz radars, increases precision
Google glass: App measures facial expression
Forget iPhone: 4 megatrends in China’s smartphone market
August 28, 2014
Touch Taiwan, an international touch-panel and optical film exhibition that opened here Wednesday, is exposing some of Asia’s ...
Foldable AMOLED features interactive touch control
Lantronix to fill digital classrooms' printing gap with PAL programme
Circular P-OLED display gives wearable device classic style
- Power Modules: The New Super Power
- Digital Power Management Reduces Energy Costs While Improving System Performance
- Using RF Recording Techniques to Resolve Interference Problems
- How to Protect & Monetize Android Apps
InterviewCEO interview: Tronics' Langlois makes moves in MEMS
Pascal Langlois has been CEO at Tronics for nine months. He discusses plans for the company and directions for the complex and diverse MEMS technology sector.
Filter WizardCheck out the Filter Wizard Series of articles by Filter Guru Kendall Castor-Perry which provide invaluable practical Analog Design guidelines.
Linear video channel
READER OFFERRead more
This month, Trinamic Motion Control is offering you to win one of four TMCM-1043 development kits for its highly integrated, NEMA 17-compatible TMCM-1043 stepDancer stepper motor module.
Offering designers an easy-to-use PC-based GUI that allows one-click modification of motor drive current, micro-stepping and other key parameters, the intuitive kits are custom designed and developed for...Read more
December 15, 2011 | Texas instruments | 222901974
Unique Ser/Des technology supports encrypted video and audio content with full duplex bi-directional control channel over a single wire interface.