All eyes on GaAs
GaAs demand from military sectors is poised for growth, but will the industry favourite fend off competition from up and coming GaN alternatives? Compound Semiconductor reports.
More than 60% of GaAs military market revenue comes from radar applications [US Navy]
With global spending on defence set to increase by 2.25% year-on-year to more than $2.1 trillion by 2023, the market for GaAs chips looks very solid.
In his recent report, 'GaAs Industry Outlook 2013-2018', Strategy Analytics analyst, Asif Anwar, predicts GaAs device demand for defence sectors will grow at almost triple the rate of commercial GaAs markets, with one of the biggest pushes coming from communications applications.
"The growth rate is higher than commercial sectors as you are starting from a relatively low level," says Anwar. "But certainly in communications applications, military markets have been catching up with a commercial sector that already has LTE-based, data-centric and IP-based communications."
As Anwar highlights, users of today's wireless devices demand Internet access, video-streaming, cameras and more. And, of course, these technologies demand linear and highly efficient compound semiconductors.
"GaAs semiconductors are the incumbent and state-of-the-art technology in cellular handsets that typically employ more than one GaAs-based power amplifier to enable operation across a spate of different frequency bands," he says. "But now we will see this GaAs-based technology being used more and more in the handheld terminals used by your war-fighters on the ground."
The second critical application for GaAs devices is, of course, radar. This sector currently accounts for more than 60% of GaAs military market revenue and will remain a hefty income earner for the technology, for some time yet.
According to Anwar, GaAs transmit/receive (T/R) modules, now standard in the active electronically scanned array radars of fighter aircraft, are rapidly transferring to different platforms. Manufacturers of naval- and land-based radar systems, for example, are turning to such solid state technology to extend capabilities of future systems.
"You may not get the same kind of volume in a naval radar system as you do in a fast-jet platform, but a naval radar can be much larger and require as many as 20,000 transmit-receive modules," says Anwar.
And as the analyst adds: "We're also seeing a replacement of traditional RF technology in systems that use a passive electronically scanned array fed by a transmitter, with a solid state-based transmitter displacing travelling wave tube-based technology."
Make way for GaN
But what about GaN? From radars to tactical jammer systems, the defence industry has spent more than a decade developing GaN for military applications.
Thanks to its high power density and efficiency, the technology has clear benefits in high performance systems, with the likes of Raytheon, TriQuint, Northrop Grumman and Cree proving its manufacturability through US Department of Defence programs.
"New radar systems are looking towards GaN as being the go-to technology," says Anwar. "Raytheon, for example, is looking to GaN for the Patriot radar while Airbus Defence & Security introduced the GaN-based TRS-4D naval radar."
But as Anwar highlights, manufacturers of GaAs-based systems don't need to worry yet. In the same way that TWT-based technologies currently underpin many radar systems and will be in operation for the next decade or more, GaAs-based technologies are not going to disappear overnight.
For starters, current military platforms, be they fighter jets or naval vessels have very long lifetimes. Mid-life upgrades are likely to see GaN-based radar systems replacing GaAs technologies, but this scenario could be at least a decade away. And right now, even the latest platforms are emerging with GaAs T/R modules.
According to Anwar, SAAB Gripen's latest fighter jet, the NG (next generation), is set to come into service come 2018 using a GaAs active electronically scanned array antenna. Similarly, planned upgrades to the Eurofighter Typhoon combat jet radar will also be underpinned by GaAs technology.
"My understanding is the Eurofighter radar is a modular design, so when the craft comes for a mid-life platform upgrade, its GaAs radar could eventually be replaced with the latest GaN-based T/R modeules," says Anwar. "Yes, GaAs technologies will see a squeeze, but developments take time in the military world and we will not see the GaAs market crashing overnight."
