Patent ID: 8003894

Claim:
A soldering structure comprising: a bus bar made of a good heat conducting metal and having a pair of parallel planar surfaces with a predetermined uniform thickness defining an aperture extending across said thickness between said surfaces, said aperture having a conical wall with a central axis substantially normal to said planar surfaces and having a cone angle at least 30°, wherein said aperture has a smaller circular opening at a first one of said planar surfaces and a larger circular opening at a second opposite one of said planar surfaces; and a terminal lead of a semiconductor device inserted in said aperture of said bus bar through said smaller circular opening so as to extend substantially along said axis of said conical aperture between said first and second planar surfaces, with said semiconductor device facing said smaller circular opening and said first planar surface, and with the terminal lead ending at or beyond said second surface, wherein at most a small gap is provided between said terminal lead and said smaller circular opening; and, a soldering material substantially filling the space formed between said terminal lead and said smaller circular aperture, said soldering material being bonded both to said terminal lead and to said conical wall of said aperture.