A fabrication method and structure for a PCBA, and tool for assembly of the structure. The structure includes a circuit board, at least one first solder joint, a plurality of second solder joints, and an electronic device. The circuit board has a solder mask, having a plurality of openings exposing at least one first pad and a plurality of second pads arranged beyond the first pad, on a surface. The first solder joint has a maximum width J1 and electrically connects to the first pad. The second solder joints respectively have a maximum width J2 exceeding J1 and respectively electrically connect to the second pads. The electronic device has a plurality of third pads, arranged substantially corresponding to the openings, respectively electrically connecting to the first pad and second pads.