| 摘要 |
PURPOSE:To dispense with a wet process, to facilitate the quality control of a wiring board, and to accurately connect layered conductive circuits by a method wherein a through-hole is provided in a required position on an insulating layer, and conductive paste is filled into the through-hole to form a through- stud. CONSTITUTION:A circuit pattern is printed on an insulating board 1 of glass epoxy with Cu conductive paste, which is dried up by heating tc form a conductive circuit 2 of a first layer. Then, insulating paste of polyurethane resin is printed covering the circuit 2, which is dried up by heating to form an insulating layer 3. Holes 4 are provided in required positions on the layer 3 by a CO2 gas laser, and Cu conductive paste is filled into the holes 4, which are dried up by heating to form through-studs 5. In succession, a conductive circuit 6 of a second layer and a pad 9 are formed through the same method as above, and lastly insulating paste of epoxy resin is printed on the conductive circuit 6, which is dried up by heating to form an insulating layer 7, and thus a two- layered circuit board can be obtained. |
