Bulletin

Issue: January/February 2008

News

Microchip with cosmic potential

At the Innovation Award ceremony, Mr Andrew Brawley, left, Executive Director of Peregrine Semiconductor Australia, and Dr Hai (Harris).

Electronics engineers and researchers from La Trobe University's Centre for Technology Infusion, Peregrine Semiconductor Australia and the CSIRO's Australia Telescope National Facility (ATNF), have jointly won an international design award for a prototype microchip with cosmic capabilities.

The three partners received the 2007 EDN Innovation Award for best Application of Analogue Design by international electronics publisher EDN magazine, for a Low Noise Amplifier (LNA) integrated chip — a chip so small it is barely visible, yet so powerful it could help detect signals from the birth pangs of the universe.

The chip is now undergoing rigorous performance testing to meet the requirements of the world's next generation listening device for monitoring the sounds of the universe. If it meets these requirements, it could be an integral part of the $1.8 billion multinational mega-science project known as the Square Kilometre Array, or SKA, the world's first global radio telescope.

Involving 17 countries and more than 50 research institutions across five continents, SKA will comprise a network of thousands of antennas straddling 3000 kilometres, with half the antennas concentrated in a five-square-kilometre radioquiet location yet to be decided, but likely to be in mid-west Western Australia or South Africa.

More than 50 times more sensitive than any existing radio telescope, the SKA will allow astronomers to detect the faintest signals from space, from the immediate aftermath of the 'Big Bang' to the death of galaxies — and all things in between, including intelligent life on other planets, if it exists, pulsars, magnetic fields, black holes and dark matter.

The project will provide science with its most technologically-advanced listening post on the planet for new answers to the riddles of existence.

In inverse proportion to its size (2.3 x 1.9 mm), the award-winning LNA microchip has been designed to address one of the SKA's most critical challenges: minimising unwanted noise in the receiver system so that radio astronomy signals from space can be more clearly distinguished.

From little things… La Trobe's Dr Hai (Harris) Le, Project Manager and Chief Designer, holds the 'cosmic' microchip on a ballpoint pen.

Fitted to the front end of hundreds of super-sensitive radio receiver circuits inside the SKA radio telescope's antennas, the chip would amplify the tiniest of intergalactic hums from outer space by 25 times, operating with very low power consumption — an extremely difficult set of electronic engineering specifications.

According to the Director of La Trobe University's Centre for Technology Infusion, Professor Jack Singh, designing the amplifier presented a formidable challenge.

'The big challenge — and the innovative design in this — is to overcome the inherent noise in an integrated circuit, and to produce an amplifier with the lowest noise possible, with broad frequency band and high gain,' Professor Singh said. 'To overcome the inherent noise, the La Trobe team used with great ingenuity the unique features of the Ultra CMOS process, using very highlinearity, high-speed transistors in combination with high Q indicators.

'The result is an excellent example of collaboration between the rare and brilliant design skills of our group at La Trobe, the domain expertise in radio astronomy at CSIRO, and a leading-edge technology process from Peregrine Semiconductor.'

After three months in design at the University's Centre for Technology Infusion, Bundoora, the chip was fabricated at Peregrine's foundries in Australia and the United States. It was then put through its paces in performance testing at CSIRO's ATNF facilities at Marsfield.

Only stringent testing will reveal whether the performance of the LNA is as good as the design model suggests. Buoyed by the results so far, the LNA team are now considering as their next project the design and implementation of a fullyintegrated receiver system using the same advanced Peregrine process.

According to Mr Andrew Brawley, Managing Director of Peregrine Semiconductor Australia, the LNA will serve not only as a prototype for developing a world-leading integrated receiver design, but — because of its capacity to operate at milli-Kelvin temperatures — will also offer prospects for the Quantum Computing Project (a multimillion dollar research quest for a supercomputer that operates at near-zero temperatures).