| 摘要 |
PURPOSE:To improve yield of article with good quality by further calcining a semiconductor porcelain substrate in a nitrogen atmosphere in a specific temperature range while applying uniform load to the whole surface of the substrate before grain boundary insulating treatment. CONSTITUTION:Raw material components consisting essentially of SrTiO2 are weighed, mixed with a binder and molded. Further, this flat board-like molded article is calcined to remove the binder component, then reduced and calcined, burnt and made into a semiconductor to give semiconductor porcelain substrates 11. Then the semiconductor porcelain substrates are vertically laminated while sandwiching setters 12 for further calcination made of ZrO2 for further calcination between the semiconductor porcelain substrates 11. The setters 12 for further calcination are used under the lowermost semiconductor porcelain substrate 11 and on the uppermost semiconductor porcelain substrate 11. 2-14g/cm<2> load is uniformly applied to the whole surface of the substrates by taking advantage of a load source or empty weight of the setters 12 for further calcination and further calcined in an atmosphere of mixed gas of N2 and H2 having <=50vol.% H2 volume ratio at 1,200-1,400 deg.C to give porcelain substrates of grain boundary insulation type. |
