Power Device Development Division
Silicon carbide (SiC) is a promising material for high power and high efficiency power devices which promote an advanced, energy-saving society. We are developing SiC crystals and epitaxial wafers using high-quality and cost effective growth technology (MPZ?*). Newly designed SiC power transistors and modules with low power loss and high blocking voltage are also being developed. Our power system equipment will incorporate these SiC power devices in the near future.
* MPZ: Multi-Parameter and Zone controlled SiC Growth Technology
High Quality SiC Crystal and Epitaxial Wafer
We are developing high quality and large diameter SiC crystals using MPZ? technology that accurately controls temperature and reaction processes during crystal growth. Single crystal epitaxial layers are grown on sliced and mirror polished SiC wafers using chemical vapor deposition (CVD). MPZ? offers high quality epitaxial wafers with world top-level uniformity, and enables a defect-free area of more than 99% of the wafer surface. The wafers have been rolled out under the trade name of EpiEra?, and were awarded 2018 Semiconductor of the Year Grand Prix Award in the electronic material division, which is sponsored by Electronic Device Industry News.
SiC power transistors are fabricated on epitaxial wafers through semiconductor processes such as ion implantation, insulating film formation, and electrode formation.
High-Efficiency SiC Power Transistor
V-grooved trench metal oxide semiconductor field effect transistors (VMOSFETs) have been newly developed by utilizing unique crystal planes. VMOSFETs have superior features such as high efficiency, high blocking voltage, and high stability under severe environments. A large current (200 A per single chip) has been achieved, which is suitable for electric vehicles (EVs) and hybrid electric vehicles (HEVs).
Furthermore, as the theoretical limit of SiC is approached, we are developing next-generation VMOSFETs with the world's lowest on-resistance in collaboration with the National Institute of Advanced Industrial Science and Technology.