ELECTRONIC PART DEVICE AND METHOD OF MANUFACTURING IT AND ELECTRONIC PART ASSEMBLY AND METHOD OF MANUFACTURING IT

摘要

If solder for joining a metal sheet to the metal surface of a board melts and erodes solder for joining an electronic part element to the metal sheet when an electronic part device in which the metal sheet is joined to the electronic part element is mounted on the board, the reliability of joining between the electronic part element and the metal sheet is lowered. A ridge (38) extending along the periphery of the bottom surface (34) of the electronic part element (22) is formed by a part of a first solder (37) for joining the electronic part element (22) to the metal sheet (23). The ridge (38) intercepts a second solder (53) for joining the metal sheet (23) to a board (32) serving as a mother board to prevent the first solder (37), which contributes to the joining of the electronic part element (22) to the metal sheet (23), from being melted and eroded.