Active solid-state devices (e.g. – transistors – solid-state diode – Lead frame – With bumps on ends of lead fingers to connect to semiconductor
Reexamination Certificate
2009-08-27
2010-12-28
Lindsay, Jr., Walter L (Department: 2812)
Active solid-state devices (e.g., transistors, solid-state diode
Lead frame
With bumps on ends of lead fingers to connect to semiconductor
C257S676000, C257S735000, C257S775000, C257S787000, C257S023000, C257SE23048, C257SE23052
Reexamination Certificate
active
07859090
ABSTRACT:
In one aspect of the invention, a method of attaching a semiconductor die to a microarray leadframe is described. The method comprises stamping an adhesive onto discrete areas of the microarray leadframe using a multi-pronged stamp tool. The adhesive is applied to the leadframe as a series of dots, each dot corresponding to an associated prong of the stamping tool. In some embodiments the adhesive used to attach the semiconductor die to a leadframe is a black epoxy based adhesive material. In an apparatus aspect of the invention, lead traces in a microarray leadframe are arranged to have tails that extend beyond their associated contact posts on the side of the contact post that is opposite a wire bonding region such that such lead traces extends on two opposing sides of their associated contact posts. The tails do not attach to other structures within the lead frame (such as a die attach structure). The width of at least some of these tailed lead traces in a region that overlies their associated contact post is narrower than their associated contact post. Thus, these narrowed lead traces have extensions that extend beyond their associated contact posts. The extensions provide additional surface area that gives an adhesive applied to the narrowed lead trace (as for example by stamping) room to bleed (flow) along the top surface of the lead trace on both sides of the associated contact pad.
REFERENCES:
patent: 5816158 (1998-10-01), Ross
patent: 6100594 (2000-08-01), Fukui et al.
patent: 6774659 (2004-08-01), Chiang
patent: 6965159 (2005-11-01), Miks et al.
patent: 6975022 (2005-12-01), Sakamoto et al.
patent: 7001798 (2006-02-01), Yamaguchi
patent: 7095096 (2006-08-01), Mostafazadeh
patent: 2004/0089929 (2004-05-01), Chiu et al.
Bayan Jaime A.
Fong Lim
Tu Nghia Thuc
Yeen Chan Peng
Beyer Law Group LLP
Lindsay, Jr. Walter L
National Semiconductor Corporation
Pompey Ron
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