| 摘要 |
PROBLEM TO BE SOLVED: To obtain a proper coefficient of thermal expansion without lowering insulating properties of a circuit board by mixing glass powder composed of SiO2, BaO and an alkali metal oxide and having a specific glass transition temperature with CuO-MnO-MoO3-Cr2O3-based compound oxide powder in a specified ratio. SOLUTION: A composition comprising 90-98 wt.% of glass powder composed of 45-60 wt.% of SiO2, 32-54 wt.% of BaO and 0.5-2.5 wt.% of an alkali metal oxide as essential components and, having 600-750 glass transition temperature and 2-10 wt.% of a compound oxide composed of 10-40 wt.% of CuO, 1-10 wt.% of MnO, 0.1-5 wt.% of MoO3 and 40-70 wt.% of Cr2O3, is baked at a temp. of 800-900 deg.C to give an electrical insulating glass ceramic circuit board constituted of a baked body having 10-18 ppm/ deg.C average coefficient of thermal expansion from a room temperature to 30 deg.C. The board can be mounted on a mother board of a glass-epoxy substrate, etc., having the similar coefficient of thermal expansion without reducing reliability and can be simultaneously baked together with metallized wiring with silver, etc. |
