| 摘要 |
PURPOSE:To improve the yield in the production of an AlN board by firing an AlN green sheet while interposing a W green sheet or a cushioning material consisting of a W paste between a setter and the AlN green sheet and between the AlN green sheet and a flatting board. CONSTITUTION:Cushioning materials 5 and 6 are interposed between a green sheet 3 and a setter 2 or between the green sheet 3 and a flatting board 4, heated in an inert gas atmosphere and burned. In this case, the materials 5 and 6 are the green sheet or paste not reacting with the green sheet 3, the m.p. of tungsten is 3387 deg.C which is the highest of all the metallic elements, and hence tungsten hardly reacts and is optimally used. Molybdenum (having 2610 deg.C m.p.) can also be used, and a green sheet or paste consisting essentially of the inorg. chemical powder having a high m.p. or decomposition temp. such as titanium nitride (having 2950 deg.C decomposition temp.), zirconium nitride (having 2700 deg.C m.p.), titanium boride and zirconium boride is conveniently used. |
