| 摘要 |
PROBLEM TO BE SOLVED: To suppress formation of bridge with a solder flowing-out between adjoining bumps when a BGA main body is soldered to a printed board, by providing a solder resist clearance with a flat-surface pattern regulating flow of a molten solder to a specific direction at soldering. SOLUTION: A protruding region provided at a part or the pattern of a solder resist removal part which is a solder resist clearance 2 cylindrically provided in the formation region of a pad 1 and its periphery, while a solder resist 3 is formed around it. The direction of projection of the resist clearance 2 provided around each pad 1 is so arranged as to be different each other by 90 deg. between adjoining pads. So, the flow-out direction of excessive solder regulated in the projection region of the solder resist clearance 2 is changed by 90 deg. to each other at adjoining pads, resulting in farthest relation in solder's flow-out direction between adjoining pads, for prevented occurrence of bridge.
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