| 摘要 |
In a method of producing a printed wiring board, solder layers are formed on pads beforehand. After the solder layers have been covered with a solder resist, the solder layers are caused to flow so as to render only the portion of the solder resist overlying the pads fragile. Then, the fragile portions of the solder resist are removed by roughening with the result that solder resist dams for preventing the solder from flowing are formed. This kind of procedure allows thick solder layers to be formed simultaneously with the solder resist dams without resorting to a great number of steps or an extra mask.
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