Method for controlling solder bump height for flip chip integrat

Details Method for controlling solder bump height for flip chip integrat Method for controlling solder bump height for flip chip integrat

1994-02-22

1995-03-28

Heinrich, Samuel M.

Metal fusion bonding

Process

Plural joints

2282481, H05K 334

Patent

active

054009502

ABSTRACT:
A method is provided for flip-chip bonding a flip chip to a substrate, which may be a ceramic substrate, printed wiring board, flexible circuit, or a silicon substrate, in which a number of input/output solder bumps are reflowed to both bond the flip chip to the circuit board as well as provide the necessary electrical connection between the flip chip and the circuit board's circuitry. The method enables the height of the input/output solder bumps to be closely controlled thereby providing sufficient spacing between the chip and its substrate, thus optimizing the cleanability and stress relief of the package. Generally, the preferred method involves the use of non-input/output, or "dummy" solder bumps which are present in sufficient numbers to overcome the tendency for the input/output solder bumps to draw the flip chip excessively close to the circuit board. Because the dummy solder bumps are electrically inactive, their height can be governed by electrically isolated pads on the surface of the circuit board. Consequently, definition of the input/output solder bumps and the dummy solder bumps does not require the use of solder stops or masks during formation or reflow of the solder bumps.

REFERENCES:
patent: 4764804 (1988-08-01), Sahara et al.
patent: 5186383 (1993-02-01), Melton et al.
patent: 5222014 (1993-06-01), Lin
patent: 5281772 (1994-01-01), Myers et al.
patent: 5323084 (1994-01-01), Haitz

Affiliated with

Also associated with

Rating

Method for controlling solder bump height for flip chip integrat does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method for controlling solder bump height for flip chip integrat, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for controlling solder bump height for flip chip integrat will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2245220