Underside heat slug for ball grid array packages

Details Underside heat slug for ball grid array packages Underside heat slug for ball grid array packages

2000-03-27

2003-04-08

Williams, Alexander O. (Department: 2826)

Active solid-state devices (e.g., transistors, solid-state diode

Housing or package

With provision for cooling the housing or its contents

C257S737000, C257S738000, C257S675000, C257S676000, C257S717000, C257S707000, C257S713000, C257S684000, C257S797000, C257S796000, C257S668000, C257S780000, C257S782000, C257S720000, C257S760000, C257S718000, C361S718000, C361S719000, C361S720000, C361S760000

Reexamination Certificate

active

06545351

ABSTRACT:

BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an integrated circuit package.
2. Background Information
Integrated circuits are typically assembled into a package that is mounted to a printed circuit board.
FIG. 1
shows an integrated circuit package commonly referred to as a plastic ball grid array (PBGA) package. The PBGA package includes an integrated circuit
1
that is mounted to a substrate
2
. Bond wires
3
may connect the integrated circuit
1
to a top surface of the substrate
2
. The integrated circuit
1
and bond wires
3
may be enclosed by an encapsulant
4
.
The package has a plurality of solder balls
5
that are attached to a bottom surface of the substrate
2
. The substrate
2
is typically a printed circuit board which has routing traces, vias, etc. which electrically connect the integrated circuit
1
to the external solder balls
5
. The solder balls
5
are reflowed to attach the package to a printed circuit board
6
.
The integrated circuit
1
generates heat which must be removed from the package. Some integrated circuit packages incorporate heat slugs, heat sinks and other thermal elements which are attached to the top surface of the package. The additional thermal elements can add to the complexity and cost of mass producing the package.
A portion of the heat generated by the integrated circuit
1
may flow into the printed circuit board
6
through the solder balls
5
. The thermal impedance through the solder balls
5
is inversely proportional to the area of the balls
5
. The solder balls
5
have a relatively small cross-sectional area. The relatively small solder ball area therefore creates a relatively high thermal impedance. The junction temperatures of the integrated circuit are proportional to the thermal impedance of the balls. A higher impedance increases the junction temperatures for a given amount of heat. It would be desirable to provide a PBGA package that more efficiently transfers heat into the printed circuit board than packages of the prior art.
SUMMARY OF THE INVENTION
One embodiment of the present invention is an integrated circuit package which includes an integrated circuit that is attached to a first side of a substrate. The package may also have a solder ball and a heat slug that are both attached to a second side of the substrate.


REFERENCES:
patent: 4602314 (1986-07-01), Broadbent
patent: 5168926 (1992-12-01), Watson
patent: 5172301 (1992-12-01), Schneider
patent: 5285352 (1994-02-01), Pastore et al.
patent: 5287247 (1994-02-01), Smits et al.
patent: 5444602 (1995-08-01), Banerjee et al.
patent: 5444909 (1995-08-01), Mehr
patent: 5450283 (1995-09-01), Lin et al.
patent: 5489801 (1996-02-01), Blish, II
patent: 5530295 (1996-06-01), Mehr
patent: 5557502 (1996-09-01), Banerjee et al.
patent: 5583377 (1996-12-01), Higgins, III
patent: 5612576 (1997-03-01), Wilson et al.
patent: 5617294 (1997-04-01), Watson et al.
patent: 5706178 (1998-01-01), Barrow
patent: 5721454 (1998-02-01), Palmer
patent: 5751063 (1998-05-01), Baba
patent: 5796589 (1998-08-01), Barrow
patent: 5805419 (1998-09-01), Hundt et al.
patent: 5812379 (1998-09-01), Barrow
patent: 5815372 (1998-09-01), Gallas
patent: 5834839 (1998-11-01), Mertol
patent: 5851337 (1998-12-01), Chen
patent: 5856911 (1999-01-01), Riley
patent: 5883782 (1999-03-01), Thurston
patent: 5894410 (1999-04-01), Barrow
patent: 5895972 (1999-04-01), Paniccia
patent: 5898219 (1999-04-01), Barrow
patent: 5903436 (1999-05-01), Brownell et al.
patent: 5917702 (1999-06-01), Barrow
patent: 5920117 (1999-07-01), Sono et al.
patent: 5920120 (1999-07-01), Webb et al.
patent: 5923086 (1999-07-01), Winer et al.
patent: 5936848 (1999-08-01), Mehr et al.
patent: 5952709 (1999-09-01), Kitazawa et al.
patent: 5972736 (1999-10-01), Malladi et al.
patent: 5990552 (1999-11-01), Xie et al.
patent: 5991156 (1999-11-01), Bond et al.
patent: 6008988 (1999-12-01), Palmer
patent: 6064117 (2000-05-01), Barrett
patent: 6156980 (2000-12-01), Peugh et al.
patent: 6194782 (2001-02-01), Katchmar
patent: 6196002 (2001-03-01), Newman et al.
patent: 6242075 (2001-06-01), Chao et al.

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