Contact structure for semiconductor device

Details Contact structure for semiconductor device Contact structure for semiconductor device

2002-12-10

2004-07-20

Pham, Long (Department: 2814)

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

Combined with electrical contact or lead

C257S341000, C257S777000

Reexamination Certificate

active

06765292

ABSTRACT:

FIELD OF THE INVENTION
This invention relates to semiconductor devices, and more specifically relates to a novel contact structure for such devices.
BACKGROUND OF THE INVENTION
Semiconductor devices used for higher current ratings (power devices which are generally those which handle in excess of one watt of power) have various types of contact structures which help to remove heat from the semiconductor die to areas external of the die or its package.
One structure which is very efficient for that purpose is the “Copper Strap” package of International Rectifier Corporation in which the top electrode, for example, the source electrode of a Power MOSFET, is contacted by a thick copper contact which efficiently extracts heat from the die, and also serves as a source contact for the device. This device is shown in U.S. Pat. No. 6,040,626, the disclosure of which is incorporated by reference herein.
Another International Rectifier Corporation patent, U.S. Pat. No. 6,396,127, discloses a semiconductor package including a semiconductor power MOSFET die having a bottom surface defining a drain connection and a top surface on which a first metalized region defining a source and a second metalized region defining a gate are disposed, the bottom surface being coupled to a first terminal; a copper plate coupled to and spanning a substantial part of the first metalized region defining the source connection, the copper plate including at least one chamfered edge extending upward and away from the first metalized region; and at least one beam portion being sized and shaped to couple the copper plate portion to the at least one second terminal such that it is electrically coupled to the source.
Another device, known as a “Direct FET” device, also made by International Rectifier Corporation, employs a flip chip type die, for example, a MOSFET with source and gate balls on one surface of the die. The back surface of the die (the drain electrode) receives a cup-shaped metal drain contact which has a flange telescoped over the edge of the die, which flange terminates in the plane of the source and gate balls. Thus, the device is easily surface mounted on a printed circuit board or the like. Such a device is shown in copending application Ser. No. 09/819,774, filed Mar. 28, 2001 entitled CHIP SCALE SURFACE MOUNTED DEVICE AND PROCESS OF MANUFACTURE in the names of Martin Standing and Hazel Deborah Schofield, pending; the disclosure of which is incorporated by reference herein.
It would be desirable to retain or improve the thermal characteristics of existing devices while also simplifying the manufacture process.
BRIEF DESCRIPTION OF THE INVENTION
The present invention relates to a novel bump strap package which has a flip-chip die with bottom source and gate bumps (for a MOSFET for example) and having a top U-shaped stress-relieving copper drain contact strap with connection ear portions at its opposite ends. A second semiconductor die (for example, an IC for the first die) can be mounted on the top surface of the drain strap.


REFERENCES:
patent: 3972062 (1976-07-01), Hopp
patent: 4646129 (1987-02-01), Yerman et al.
patent: 6040626 (2000-03-01), Cheah et al.
patent: 6127727 (2000-10-01), Eytcheson
patent: 6262489 (2001-07-01), Koors et al.
patent: 6396127 (2002-05-01), Munoz et al.
patent: 6521982 (2003-02-01), Crowley et al.
patent: 2003/0127729 (2003-07-01), Fukumoto et al.

Affiliated with

Also associated with

Rating

Contact structure for semiconductor device does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Contact structure for semiconductor device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Contact structure for semiconductor device will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3256853