Technical Insight
All change for silicon carbide
With continued growth projected for SiC markets, up and coming Japan-based manufacturers prepare to steal the show, reports Compound Semiconductor.
As manufacturers of photovoltaic inverters and high-end power supplies embrace SiC diodes and transistors, wide bandgap device makers are braced for growth and change.
Highlighting how the SiC device market bucked the power electronics downturn and grew 38% in 2012, Yole Developpement analyst, Philippe Roussel, forecasts continued growth, but not necessarily for the likes of Cree, Infineon, Microsemi and ST Microelectronics.
“It's a funny story but come 2020 the dominant country in the silicon carbide business will be Japan,” he says. “In the coming seven years, Japan will grow from zero to [holding] the majority of the business, some 35%.”
Looking east, Rohm is Japan's key SiC device manufacturer right now, but many other Japan-based businesses have also been rapidly developing related technologies.
As Roussel puts it: “Japanese companies are really pushing like hell on silicon carbide development and now have plenty of really smart technology in-house. We've seen them really expand their businesses in the last two years and now they are moving to the next phase; commercialisation.”
Indeed, the nation's electronics conglomerates from Fuji Electric and Mitsubishi Electric to Panasonic and Toshiba have already unveiled myriad SiC discrete diodes, transistors and power modules. Following in the footsteps of Cree and Rohm, a key focus right now is MOSFETs with integrated diodes, but more can be expected.
“We are in touch with these companies and know they have everything they need to compete with state-of-the-art technologies,” he adds. “So now they are really pushing to launch commercial versions.”
Crucially, the majority of Japan-based electronic heavyweights have focused on the MOSFET. Could a plentiful source of MOSFETs finally sway industry favour towards this tried and tested transistor? As Roussel puts its: “Hitachi, Mitsubishi, Nissan, Panasonic and Toshiba... yes, they are all working on the MOSFET.”
The answer is not yet obvious. And as the likes of Infineon, Fairchild and United SiC continue to focus on JFET, BJT and IGBT development, key questions remain.
What markets will the new wave of wide bandgap product manufacturer target? And will these electronics heavyweights actually deliver discrete devices or implement ICs into modules?
Looking at markets, today's leading lights have targeted many applications. For example, Germany-based Infineon has set its sights on existing smart power modules and PV inverters while and Cree, US, with its diversified product range targets these and other markets. Japan-based players appear to be choosier.
“Rohm is really promoting silicon carbide for hybrid electric vehicles while Mitsubishi is producing silicon carbide for train traction,” he says. “My feeling is if the hybrid electric vehicle market [takes off]... the Japanese will be well positioned to address it.”
But markets aside, the jury is out on whether these players will supply discretes or modules. Roussel now sees the entire SiC industry re-shaping, moving from a discrete device business to a power module business. As he points out, this was initiated by the likes of MicroSemi and GeneSiC delivering hybrid silicon/silicon carbide products while other players such as Rohm and Mitsubishi have now unveiled full-SiC modules.
While the analyst predicts this trend will prevail in the coming years, exactly what the Japan-based players do next remains to be seen.
“Fuji for example proposes to build a silicon carbide manufacturing line with a government-founded national program. This line will be shared between several partners and the idea is to develop devices,” he explains. “And so the question is what are these companies going to do with these devices. Will they be sold as discretes or implemented in a power module?”
As Roussel highlights, Fuji Electric already manufactures power modules, Panasonic develops devices but sells systems while Mitsubishi Electric uses its SiC diodes and MOSFETs internally for, say, air conditioning systems.
“It really is a question of, say, will Fuji sell discrete devices? I just don't know,” he asserts. “My feeling is Japan already has an established domestic market and so [these players] can do whatever they want.”
