PURPOSE: To make a high frequency window superior in pass rate and resist the transmission of the high frequency of high output by using ceramics whose principal components are Si-Al-C-N as the material of the high frequency window, and compounding, for instance, AIN ceramics and SiC ceramics.
CONSTITUTION: The ceramics consists of aluminum nitride particles and matrix to bond the aluminium particles, and the matrix occupies 0.1-50weight%. The ceramics consists of the matrix a part more than 50weight% of which is SiC and the rest of which is the oxides of Al, Si, and its principal components are Si-Al-C-N. In this case, since the fine-grained sintered body is difficult to obtain by using only AIN and SiC, and airtightness is difficult to secure, a little quantity of sinter assistant is added. The oxides of Al, Si of low induced radioactivity are added by less than 15weight% as the sintering assistant. The ceramics of the principal components of Si-Al-C-N is fitted to the waveguide by a well-known method.
MURAKAMI YOSHIO
HIROKI SEIJI
MATSUNUMA KENJI
MIYAKE MASAYA
OOKA SHINYA
SUMITOMO ELECTRIC INDUSTRIES