Active solid-state devices (e.g. – transistors – solid-state diode – Lead frame
Patent
1997-06-30
1999-05-18
Williams, Alexander Oscar
Active solid-state devices (e.g., transistors, solid-state diode
Lead frame
257671, 257669, 257687, 257676, H01L23/495;23/498;23/48;23/06
Patent
active
059053003
ABSTRACT:
A method and apparatus for a reinforced leadframe to substrate attachment in a semiconductor assembly. In one embodiment, a printed circuit board having a plurality of electrically coupled electrical contact regions and wire bond areas formed thereon has a leadframe attached thereto such that each of the bonding fingers of the leadframe is coupled to a respective electrical contact region on the printed circuit board. A ribbon of B-staged epoxy is disposed on the leadframe such that the leadframe is disposed between the ribbon of B-staged epoxy and the printed circuit board. An integrated-circuit die is mounted on the printed circuit board with the bonding fingers of the leadframe peripherally surrounding the integrated circuit die. The bonding pads on the integrated-circuit die are electrically coupled to respective wire bond areas on the printed circuit board. By placing the ribbon of B-staged epoxy over the leadframe, the connection between each bonding finger of the leadframe and the respective electrical contact region is reinforced. Thus, the present claimed invention reduces separation between each bonding finger of the leadframe and the respective electrical contact region of the printed circuit board thereby providing improved reliability and yield in such semiconductor assemblies.
REFERENCES:
patent: 3999285 (1976-12-01), Lewis et al.
patent: 4048438 (1977-09-01), Zimmerman
patent: 4139859 (1979-02-01), Lewis et al.
patent: 4385202 (1983-05-01), Spinelli et al.
patent: 4472762 (1984-09-01), Spinelli et al.
patent: 4546374 (1985-10-01), Olsen et al.
patent: 4546406 (1985-10-01), Spinelli et al.
patent: 4631805 (1986-12-01), Olsen et al.
patent: 4721994 (1988-01-01), Mine et al.
patent: 4736236 (1988-04-01), Butt
patent: 4967260 (1990-10-01), Butt
patent: 5079673 (1992-01-01), Kodai et al.
patent: 5086334 (1992-02-01), Eberlein
patent: 5107325 (1992-04-01), Nakayoshi
patent: 5173766 (1992-12-01), Long et al.
patent: 5175060 (1992-12-01), Enomoto et al.
patent: 5243496 (1993-09-01), Mermet-Guyennett
patent: 5279029 (1994-01-01), Burns
patent: 5281851 (1994-01-01), Mills et al.
patent: 5316204 (1994-05-01), Takehashi et al.
patent: 5359222 (1994-10-01), Okutomo et al.
patent: 5410182 (1995-04-01), Kurafuchi et al.
patent: 5528077 (1996-06-01), Tane et al.
patent: 5552631 (1996-09-01), McCormick
patent: 5637919 (1997-06-01), Grabbe
patent: 5704593 (1998-01-01), Honda
patent: 5731631 (1998-03-01), Yama et al.
patent: 5751060 (1998-05-01), Laine et al.
patent: 5767570 (1998-06-01), Rostoker
King Patrick T.
VLSI Technology Inc.
Williams Alexander Oscar
LandOfFree
Reinforced leadframe to substrate attachment does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Reinforced leadframe to substrate attachment, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Reinforced leadframe to substrate attachment will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1761580