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
Mouser launch design contest around NXP's dual PCB configurable logic
November 26, 2014
At electronica, NXP Semiconductors N.V. introduced its line of multi-gate, multifunction, dual PCB configurable logic devices ...
Smart PCBs for smaller ECUs: Infineon invests in PCB manufacturer
FTTH solutions for MDUs
Tiny LED makes bionic contact lenses realistic
How does a Blu-ray disc improve solar cell performance?
CEO interview: Vicor powers after higher volume applications
November 26, 2014
Patrizio Vinciarelli, is one of the longest serving CEOs in electronics, having founded Vicor in 1981 and led the company ...
Wireless power receiver enables compact and efficient contactless battery charging
Advanced wheel hub drive passes extensive driving tests
CEO interview: Murata succumbs to IoT temptation
- Power Systems Design eBook
- Halogen-free options and increased performance for terminal blocks
- Wireless Power User Guide
- Secure is the New Smart
InterviewCEO interview: Vicor powers after higher volume applications
Patrizio Vinciarelli, is one of the longest serving CEOs in electronics, having founded Vicor in 1981 and led the company ever since. At Electronica he told EE Times Europe that his company is investing ...
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, Cherry is giving away five of its Energy Harvesting Evaluation kits, worth over 266 Euros each, for EETimes Europe's readers to win. Cherry's energy harvesting technology benefit mostly applications where a complex wire assembly and/or batteries would be inappropriate.
The required RF-energy is created by the mechanical actuation of the switch and the data is transmitted...MORE INFO AND LAST MONTH' WINNERS...
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.
Most popular news
- Could magnesium battery innovation end lithium's dominance?
- From warm to cool white: colour-temperature tunable LEDs
- Li-Fi communication module wirelessly transfers data at 1-Gbps
- Rebranding the revolution: the future of IoT is embedded
- Supercapacitor innovation promises panel-powered cars in five years