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Research paper−245−Synthesiology - English edition Vol.3 No.4 pp.245-258 (Mar. 2011) in relation to the changes in the changes in the organization of AIST. Finally, the future issues will be discussedNote 1 (Table 1).2 Goals of R&D at various periods2.1 Position of R&D in the whole pictureRecently in Japan, the energy issue in 2100 was discussed in terms of the limited resources and environment, and the direction of the technological development was laid out to deal with the issue[1]. It is estimated that sustainable development will be possible only through thorough energy saving by using electric power that is superior in efficiency, convenience, and economy, and such power is attainable by the massive introduction of renewable energy and nuclear power. Needless to say, power electronics will become important as the common basic technology that will be the key to the effective use of electric power. The key technology of power electronics is power device. While the researchers try to increase performance by improving the design of the structure of the current silicon semiconductor power device, it is approaching the theoretical limit calculated from the physical parameters of silicon. The major performance index of a power device is how low the loss is. To achieve the low-loss property, the low on-resistance (where the resistance during current conducting is low) and high switching speed are required. In the SiC wide-bandgap semiconductor that has a band gap about three times greater than silicon, the dielectric breakdown field is about one digit greater than silicon, and the theoretical limit of the on-resistance is less by two digits. In silicon, a power device with low on-resistance yet with low switching speed (IGBT) has been developed, although its application is limited. The SiC power device that allows low on-resistance and high-speed 1 IntroductionAt the 15 institutes under the former Agency of Industrial Science and Technology that was the precursor of the current National Institute of Advanced Industrial Science and Technology (AIST) in the 1990s, majority of the researchers were material researchers. In the long-term material research, how we can present our importance to society was a subject of frequent discussions. In the late 1980s, the United States was experiencing economic slowdown, and the American basic researchers were visiting Japan to sell their research. The Japanese national research institutes at the time were in the phase of “shift to basics” or putting emphasis on leading-edge basic research. Some material researchers armed with their specialties engaged in the study of whatever material that was in vogue at the time. At the Electrotechnical Laboratory (ETL), a consciousness shift was promoted under the concept “material is useful only when it is used”. The ETL was being left behind in the state-of-art technological development of silicon LSI, but was starting a series of pioneering R&D in the field of materials. It was concluded that to study the material group with prospects for practical utilization in future electronic devices, emphasis should be placed on the wide-bandgap semiconductors such as silicon carbide (SiC) as well as gallium nitride (GaN) and diamond that were expected to achieve low-loss high-frequency operation and high-temperature high-radiation resistance (Fig. 1).In this paper, the development of the SiC semiconductor power device and the activities toward its practical utilization will be explained in terms of 1) the research goal, 2) the individual issues and strategies for solutions and the results, and 3) the evaluation of the adequacy of the strategy, - The role of AIST in developing new semiconductor devices-Kazuo AraiPlanning Division, Research and Innovation Promotion Headquarters, AIST Tsukuba Central 2, 1-1-1 Umezono, Tsukuba 305-8568, Japan E-mail : Original manuscript received March 6, 2009, Revisions received March 15, 2010, Accepted March 29, 2010The realization of SiC semiconductor power devices has been highly expected to contribute to energy saving, however, it requires overcoming various technological barriers. AIST has been contributing to this objective for more than 15 years mainly through participation in national projects. Corresponding to the changes of organization of the institute, in this paper, R&D activities for the past years are described in three parts, i.e., 1) the R&D targets, 2) the major issues and strategies for overcoming them and the main results, 3) the evaluation of the validity of the strategies, and lastly, future issues are suggested.R&D of SiC semiconductor power devices and strategy towards their practical utilizationKeywords : Silicon carbide, wide-gap semiconductor, wafer technology, power semiconductor device, power electronics[Translation from Synthesiology, Vol.3, No.4, p.259-271 (2010)]

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