| 摘要 |
PROBLEM TO BE SOLVED: To enhance fine line printing of an upper conductor circuit on a glass layer by immersing the glass layer formed on a lower conductor circuit into an aqueous solution of organic acid thereby making the surface smooth. SOLUTION: A lower conductor material is applied and printed onto a support board of alumina or the like and then dried and fired to form a lower conductor circuit. In order to ensure insulation between the upper and lower conductor circuits, a glass material is applied and printed onto the lower conductor circuit and then it is dried and fired to form an insulator, i.e., a glass layer. The glass layer is then immersed into an aqueous solution of organic acid, e.g. citric acid or ammonium citrate, for the purpose of surface treatment. In this regard, the glass layer required as an insulator is left as it is and only the irregular part on the surface is removed thus forming a glass layer having a smoothed surface. Finally, the upper conductor circuit is formed on the glass layer. According to the method, a conductor circuit excellent in fine line printing can be formed. |
