Toyoda Gosei Co Ltd of Kiyosu, Aichi Prefecture, Japan has developed what is claimed to be the first 1.2kV-class power semiconductor device chip capable of large-current operation exceeding 20A.
Picture: Forward current–voltage characteristics.
Using gallium nitride (GaN) crystal growth technology developed since 1986 for the production of blue LEDs, Toyoda Gosei began research on GaN-based power semiconductor devices in 2010. Previously, low-loss 1.2kV-class MOSFETs were fabricated on GaN substrates and then empirically tested (achieving 1.8mΩcm2, when current is passed via a structure in which current flow is perpendicular to the substrate and gate trenches).
Toyoda Gosei says that it has now established wiring technology for parallel operation of elements, passing a current exceeding 20A in a vertical GaN transistor with a 1.5mm x 1.5mm chip size (the first time that this has been achieved, reckons the firm).
Picture: Toyoda Gosei's new MOSFET chip (photomicrograph).
The technology can be applied to circuits for power controllers in hybrid vehicles that handle large amounts of power, and to power converters such as those in solar power generation, promising to contribute significantly to making these devices more compact and efficient.
Toyoda Gosei says that it will continue research to increase the current-handling capacity and test reliability, with the aim of developing commercial applications by 2018-2020 in collaboration with semiconductor and electronics manufacturers.
A report on this technology was presented as a 'late news' paper at the 28th IEEE International Symposium on Power Semiconductor Devices and ICs (ISPSD) in Prague, Czech Republic (12-16 June).
