| 摘要 |
PROBLEM TO BE SOLVED: To prevent failure of soldering in a mounting land at the end of a substrate by outwardly and excessively coating cream solder on a mounting land provided at the end of the substrate compared to the inner mounting lands. SOLUTION: Cream solder 6 is outwardly and excessively coated on part foot lands 5a and 5b provided at the end of a substrate compared to an inner part foot land 5. When the cream solder 6 is excessively coated, extrusion of the cream solder 6 is enlarged outside the part foot lands 5a and 5b at the end of the substrate in introducing into a reflowing furnace. In this state, when introducing into the reflowing furnace, the cream solder 6 begins melting and also cohering, but a large quantity of cream solder 6 is not drawn toward the inner part foot land 5 because a large quantity of cream solder 6 is present outside the part foot lands 5a and 5b at the end of the substrate. Consequently, solders 7 can be formed without insufficient solder on part foot lands 5, 5a and 5b.
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