Co-Investigator(Kenkyū-buntansha) |
佐藤 純一 昭和電工(株), セラミックス事業部, 部長
ISHIGURO Takashi Nagaoka University of Technology, Department of Electrical Engineering, Associat, 工学部, 助教授 (10183162)
SATOH Junich Showa Denkou Co., Ltd., Ceramic Section, Head of Ceramic Section
|
Research Abstract |
Present research has been performed with the aim of forming large single crystals of diamond or especially cubic boron nitride (cBN) by means of the plasma CVD method. It was thought to be important to choose materials for substrate to make epitaxial crystal growth. When an ordinary silicon substrate was used, only polycrystal film could be obtained. Compared with this, on the silicon substrate scratched by diamond, the production rate of cBN was improved because of remaining of diamond fine seed crystals. For the next step, cBN or diamond with a mu m size were used as seed crystals, however, the deposited matter was polycrystallized due to the plasma irradiation. To avoid the degradation in cBN or diamond, a hot-filament CVD method, in which excitation level of raw material was lower than that of rf plasma CVD method, was adopted. In this method, the required conditions in formation of cBN, i. e., thermal stability of cBN and preferential etching effect, were confirmed, but the deposition of hexagonal BN was too fast to confirm cBN synthesis. As a final result, the methodological contradiction in a plasma CVD method to form large single crystals was cleared.
|