Method for supplying solder

• Main Authors: OHASHI YUJI, FURUNO MASAHIKO, ANDOU HARUHIKO, ONOZAKI JUNICHI, SHIRAI MASARU, SAITO HIROSHI, SAKAMOTO ISAO
• Format: Patent
• Language: English
• Published: 01.04.2008
• Subjects: BASIC ELECTRIC ELEMENTS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; MACHINE TOOLS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS; METAL-WORKING NOT OTHERWISE PROVIDED FOR; PERFORMING OPERATIONS; PRINTED CIRCUITS; SEMICONDUCTOR DEVICES; SOLDERING OR UNSOLDERING; TRANSPORTING; WELDING; WORKING BY LASER BEAM

Obtained are fine-pitched pad electrodes and also solder bumps with a large amount of solder and a less difference in the amount. First, in an inert liquid in a liquid tank, a substrate is positioned with a surface facing up. Subsequently, the inert liquid containing solder fine particles is fed from a solder fine particle forming unit to the liquid tank and the solder fine particles are dropped from a supply pipe onto the substrate in the inert liquid. The solder fine particles naturally fall down by the gravity, thereby reaching the substrate. The solder fine particles reached on the pad electrodes on the substrate stay there due to the gravity, and spread on the surfaces of the pad electrodes after the solder wet time, thereby forming solder coating.