Hiroyuki Matsunami wins Honda prize for SiC research
Professor emeritus of Kyoto University recognised for contributions to pioneering research on SiC power devices and their practical applications
Honda Foundation has announced that the Honda Prize 2017 will be awarded to Hiroyuki Matsunami, professor emeritus, Kyoto University for his contributions to pioneering research on SiC power devices and its practical applications.
Established in 1980, the Honda Prize is Japan's first international award in the field of Science and Technology. It is awarded annually to an individual or group to recognise accomplishments in the field of ecotechnology, which works to advance human achievement while concurrently preserving the natural environment.
Matsunami is the 38th Honda Prize laureate. The award ceremony will be held at the Imperial Hotel in Tokyo, Japan on November 16, 2017. In addition to the prize medal and the diploma, the laureate will be awarded 10 million yen.
As a new material, research on SiC started in mid 1950s in the United States. Matsunami had an interest in SiC from early on, and started basic research from the late 1960s to develop electronic devices usng SiC's excellent physical properties - high-temperature operability and radiation resistance.
While Si has a characteristics of a single crystal with a regular diamond structure, SiC is a hard-to-handle material as performing crystal growth with few defects was difficult. Also SiC has 200 different types of crystal structure states (crystal polymorphism), the most appropriate crystal polymorphism for commercialisation was not yet determined. Furthermore, with a robust structure as hard as diamond, SiC makes its processing extremely difficult and challenging. Although many research institutes attempted to realise SiC's practical applications, none overcame the difficulties in processing and most of them withdrew from the project.
Matsunami continued basic research on SiC and, about 20 years from the commencement of his research, in 1987, he published a method called 'Step-Controlled Epitaxy' enabling production of homogeneous SiC thin membrane with uniformed crystal polymorphism by tilting the surface of a substrate a few degrees. Around 1990, as Si power devices were facing their performance limit, thanks to his discovery, the SiC utilisation came under the world's spot light and development of the SiC power devices dramatically advanced.
Around 2010, a practical application of SiC power devices has started. Using SiC in power devices led to a tremendous reduction in power loss, enabling high-speed, high-efficiency power control. Likewise, as SiC has high-voltage resistance and high-temperature resistance characteristics, cooling systems became more compact, leading to downsizing of power control mechanisms. In 2013, SiC power devices were introduced to Tokyo Metro subway and registered a 30 percent energy reduction compared to the amount of energy required by conventional train cars.
In recent years, SiC power devices have been installed on such as suburban trains, high-speed elevators, power conditioners for solar batteries, fuel cell vehicles, and experiments for installation on hybrid cars and the Tokaido Shinkansen have been started as well.
Although there are still some challenges in dissemination of SiC power devices including establishment of mass-production technology, cost reduction, and so forth, its application to electric vehicles is also expected when further reduction in power consumption, space-saving through downsizing of the devices, and cost reduction are achieved.
Starting with Step-Controlled Epitaxy developed through long years of Matsunami's research, SiC production method and the technologies enabling the practical applications of SiC to power devices have paved the way for new possibilities for SiC as a novel material. As realisation of the practical uses of SiC power devices would also lead to resolution of a rapid increase in fossil fuel consumption and the amount of waste from power generation accompanied by a surge in power consumption on a global scale, his accomplishments were considered appropriate for the Honda Prize recognition.