| 摘要 |
PURPOSE:To enable lead metallic layers to be effectively prevented from being shorted, by piling a second unfired ceramic sheets having perforated holes, whose diameters are different from that of the perforated hole of a first ceramic sheet, on the first unfired ceramic sheet so that their perforated holes are disposed to be essentially matched to each other. CONSTITUTION:First and second unfired ceramic sheets 2 and 3 are piled in order so that centers 5 and 6 of respective perforated holes are matched to each other, and be thermally pressed by using a hot press to form a piled unfired ceramic body 1. Successively metallic layers 8 for lead, coated with metallic paste by printing method, are formed on the inner walls and upper planes of the perforated holes 6 of the second unfired ceramic sheets 3 in this piled unfired ceramic body 1. The unfired ceramic body 1 is fired in a reduction atmosphere, so that metallic layers 4 and 8 for die attachment and lead, respectively, are sintered/unified with the piled unfired ceramic body 1, to form a fired ceramic body, die attachment, metallic layer, and a lead metallic layer. Finally the fired ceramic body formed in this way is cut/separated along a division line C which is determined by disposal of the perforated holes. |
