| 摘要 |
PROBLEM TO BE SOLVED: To simplify works by a method, wherein a space enclosed with a soft sheet and a mounting tool is decompressed, and by making use of a pressing force of the soft sheet due to compression, apexes of a plurality of bump-like connection terminals exposed through transparent holes are flattened. SOLUTION: The entire surface on the upper face of a plurality of wiring boards is coated with a soft sheet 14 composed of silicon rubber, and a reinforcing plate 2 and a wiring substrate main body 6 overlaid via an adhesive sheet 10A are enclosed with the soft sheet 14 and a mounting tool 11. Next, a space enclosed by the soft sheet 14 and the mounting tool 11 and surrounded by an exhaust pipe 12 is decompressed. After a preliminary heating is performed under the decompression, the adhesive sheet 10A is heated at 170 deg.C for 60 min and is cured, and pressure from the soft sheet 14 due to compression is exploited, while the reinforcing plate 2 is adhered to the wiring substrate main body 6. Here at the same time, after the apex of a solder bump 8 is flattened under a pressure from the soft sheet 14, the soft sheet 14 is removed to complete a wiring substrate. |
