摘要 |
A method of forming a semiconductor device mounts solder balls on a resin board which has holes formed therethrough and conductive sheets formed therebeneath to cover bottom ends of the holes. The method includes the steps of applying solder paste on the holes, melting the solder paste by heat to make solder of the solder paste flow into the holes and establish contact with the conductive sheets, and connecting the solder balls to the solder filled in the holes. |