Cut-out heat slug for integrated circuit device packaging
View Patent ↗In a package, a heat slug, encapsulated by molding compound, encases an integrated circuit device (IC). In an example embodiment, a semiconductor package structure comprises a substrate having conductive traces and pad landings. The conductive traces have pad landings. An IC is mounted on the substrate. The IC has bonding pads. With conductive wires, the IC bonding pads are connected to the pad landings, which in turn, are connected to the conductive traces. A heat slug, having predetermined height, is disposed on the substrate surface. The heat slug includes a plurality of mounting feet providing mechanical attachment to the substrate. A cavity in the heat slug accommodates the IC. A plurality of first-size openings surrounds the IC. A second-size opening constructed from one of the first size-openings, is larger than the first-size opening. The second size-opening facilitates the introduction of molding compounds into the cavity of the heat slug.
1. A semiconductor package structure, comprising:
a substrate, the substrate having conductive traces, the traces having pad landings; an integrated circuit device (IC) mounted on the substrate, the IC having bonding pads; a plurality of conductive wires connecting the IC bonding pads with the pad landings connected to the traces;
a heat slug having a predetermined height disposed on the surface of the substrate, the heat slug including a plurality of mounting feet the mounting feet providing mechanical attachment of the heat slug to the substrate,
a cavity to accommodate the IC device,
a plurality of first-size openings, the plurality of first-size openings surrounding the IC device;
a second-size opening, the second size opening constructed from one of the first-size openings the second-size opening being larger than the first-size opening, the second-size opening facilitating the introduction of molding compound into the cavity of the heat slug.
2. The semiconductor package structure of claim 1 , wherein the second-size opening is larger than one of the first-size openings.
3. The semiconductor package structure of claim 1 , wherein the second-size opening displaces a location otherwise adapted for one of the plurality of mounting feet.
4. The semiconductor package structure of claim 1 , wherein the predetermined height of the heat slug is greater than or equal to that of a cavity of an encapsulating mold.
5. A heat slug comprising:
a lower portion, the lower portion having a plurality of mounting feet;
an upper portion, the upper portion having a cavity, the cavity of sufficient size to accommodate an integrated circuit device;
a plurality of first-size openings, the plurality of first-size openings surrounding the IC device;
a second-size opening, the second size opening constructed from one of the first-size openings, the second-size opening being larger than the first-size opening, the second-size opening facilitating the introduction of molding compound into the cavity of the heat slug.
6. The heat slug of claim 5 , wherein the second-size opening displaces a location otherwise adapted for one of the plurality of mounting feet.
7. The heat slug of claim 5 , wherein the upper portion has a height greater than that of a cavity of an encapsulating mold.
8. The heat slug of claim 5 , wherein the plurality of mounting feet is at least three.
9. The heat slug of claim 8 , wherein the plurality of mounting feet further includes additional mounting feet in the vicinity of the second size opening.
10. A high performance ball grid array (HBGA) package structure, comprising:
a substrate, the substrate having conductive traces, the traces having pad landings; an integrated circuit device (IC) mounted on the substrate, the IC having bonding pads; a plurality of conductive wires connecting the IC bonding pads with the pad landings connected to the traces;
a heat slug having a predetermined height disposed on the surface of the substrate, the heat slug including
a cavity to accommodate the IC device,
a plurality of first-size openings, the plurality of first-size openings surrounding the IC device;
a second-size opening, the second size opening constructed from one of the first-size openings the second-size opening being larger than the first-size opening, the second-size opening facilitating the introduction of molding compound into the cavity of the heat slug; and
a plurality of mounting feet the mounting feet providing mechanical attachment of the heat slug to the substrate, wherein the plurality of mounting feet further include additional mounting feet in the vicinity of the second size opening.
11. A method of bonding an integrated circuit die (IC) to a substrate, the method comprising:
placing the IC on the substrate;
attaching the IC to the substrate;
wire bonding the IC to the substrate;
disposing a heat slug over the IC and attaching the heat slug to the substrate, the heat slug including,
a plurality of mounting feet, providing mechanical attachment of the heat slug to the substrate,
a cavity to accommodate the IC device, and a plurality of first-size openings surrounding the IC;
a second-size opening constructed from one off the first-size openings the second-size opening being larger than the first-size opening, the second-size opening facilitating the introduction of molding compound into the cavity of the heat slug; and
injecting molding compound into the second-size opening of the heat slug.
12. The method of claim 10 , wherein injecting the molding compound, includes prior to injecting the molding compound, surrounding the heat slug with an encapsulation mold.