| 摘要 |
PURPOSE:To reduce baking time and cost of a multilayer ceramic circuit board in which copper is employed as a wiring material by introducing a firing step in the air atmosphere particularly in case of binder removing. CONSTITUTION:Paste containing copper power having 0.05-1.0m<2>/g of BET specific surface area as main ingredient is printed on a green tape made of a ceramic material to be fired at a lower temperature than the melting point of copper and thermoplastic resin, laminated, thermally press-adhered, and integrated unfired material is fired. It is so fired to remove binder in the air atmosphere that carbon residue becomes 600-1500ppm at a temperature of buckling point or less of glass component in the unfired material. Then, it is so sintered in a nitrogen atmosphere that carbon residue becomes 300ppm or less at 800-1000 deg.C. An example of the ceramic material includes mixture powder of glass component of CaO-(MgO)-Al2O3-SiO2-(B2O3) and Al2O3 as low temperature fired ceramic material sintered at 800-1000 deg.C. |
