| 摘要 |
<p>PROBLEM TO BE SOLVED: To suppress warpage of a solder ball transfer sheet as well as disloca tion of a solder ball which has been transferred by forming a reinforcing plate on an opposite surface, where no conductor element is formed, on a base resin which is to be a base for a solder ball transfer sheet. SOLUTION: A solder ball transfer sheet 1 comprises a base resin 2, conductor terminal 3, and reinforcing plate 30. Firstly, a reinforcing plate 30' is laminated on a surface of the base resin 2, one of a 2-layer sheet comprising the base resin 2 and a metal plate 6, which does not contact the metal plate 6. An etching mask 7 is formed on the metal plate 6, which is etched to form a metal core 4. Then the etching mask 7 is released and a solder coat 6 constituting a part of a conductor terminal 3 is formed on the surface of the metal core 4 by electroless plating to provide a ball transfer sheet 6. The reinforcing plate 30 may be of any such material as suppresses warping of the solder ball transfer sheet 1.</p> |
