Associate Prof. Kei Kamata (concurrently serving as President of C&A,Tohoku University Venture) and Prof. Akira Yoshikawa (concurrently serving as IMR) have developed a new crystal growth method, Oxide Crystal growth from Cold Crucible method, which does not use precious metal crucibles, and succeeded in producing Gallium oxide crystals (up to about 5 cm in diameter), which are expected to be used as next-generation power semiconductors, have been successfully fabricated.
Conventional crystal growth methods use iridium (crucible material: approx. 15,000 yen/g, market price in February 2022), a precious metal, for the crucible that holds the melt, which causes the following problems: (1) it is extremely difficult to reduce crystal costs, and (2) oxygen defects are generated by the manufacturing process.
In this development, based on the skull-melt method, which is a crucible-free crystal growth method, C&A has succeeded in producing high-quality gallium oxide crystals without the use of precious metal crucibles by developing original equipment.
This achievement makes it possible to produce gallium oxide substrates at low cost and is expected to contribute significantly to the realization of low-loss gallium oxide power semiconductors.
This research was conducted under the “Miyagi Prefecture New Energy and Other Environment Related Equipment Development Support Project” and the “Fundamental Technology Development Project for Innovative Power Electronics” of the Ministry of Education, Culture, Sports, Science and Technology of Japan.
Related materials:
Tohoku University press release page (Japanese) (click here)
IMR press release page (Japanese) (click here)