PURPOSE: To enhance mounting density of a device by connecting a component mounted on a conductive pattern covering the surface of a metal plate through a thermoplastic polyimide film and contracted, to a flat platelike second board, and sealing it.
CONSTITUTION: A predetermined electronic component is mounted on a predetermined bonding pad on a copper foil 14, formed in a cap state by covering the surface of a metal plate 12 with a thermoplastic polyimide film 13, covering thereon with the foil 14 to form a first board 11 and contracting the board 11, and electrically connected to the pad. It is placed at a predetermined position of a flat platelike second board 21 similarly formed thereto, so disposed as to electrically connect between predetermined conductor patterns, and the first board is soldered 28 to the second board. Further, after the connecting position is hermetically sealed with a sealing material 29, the peripheral edge of the board 21 is bent, and a conductive foil 24 is disposed downward. Thus, mounting density of a hermetic type electric circuit device can be enhanced by an inexpensive structure.
HOSONO YOICHI
ISHIKAWA TAKAYUKI
