[sci.electronics] Salvaging Defective IC's

mmm@cup.portal.com (Mark Robert Thorson) (09/21/89)

In the latest issue of NASA Tech Briefs, there is an interesting article
on a technique for eliminating cracks and voids in aluminum lines of
chips.  The technique is to bake the chip at 200-400 degrees C for 30 minutes
then plunge it into liquid nitrogen.  The article shows photos of an
aluminum interconnect line both before and after treatment.  No discussion
of the mechanism is presented.

BTW, NASA has applied for a patent on this technique.

I've heard of a similar technique being used to treat defective EPROM's.
I believe the old (circa 1975) Intel memory design books mentioned that
defective 1702's could sometimes be recovered by baking in an oven for
roughly the temperature and period of time used by the NASA people.