Method for testing encapsulation integrity

Chemistry: electrical and wave energy – Processes and products – Processes of treating materials by wave energy

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

204401, G01N 2726

Patent

active

050769065

ABSTRACT:
A procedure is disclosed for detecting and documenting flaws in the glassivation layer protecting the active device region of an integrated circuit. A droplet of dilute sulfuric acid solution is placed on top of the glassivation layer and a positively biased electrode is immersed in it. The leads coupled to circuit under the glassivation layer are coupled to a more negative voltage. The release of hydrogen bubbles into the solution through flaws in the glassivation via an electrolysis reaction are readily observable. Defects in a glassivation layer over nichrome devices may be documented by reversing the polarity of the bias to cause a reversal of the electrolysis process and a release of oxygen from the defective sites. This causes oxidation and disfigurement of the nichrome which can be documented using ordinary photographic means. Defects in a glassivation layer over aluminum may be documented by replacing the droplet of dilute sulfuric acid with a droplet of dilute sodium chloride; the resulting disfigurement may be photographed.

REFERENCES:
patent: 3408270 (1968-10-01), Gentile
patent: 3494837 (1966-10-01), Messner et al.
patent: 4514436 (1985-04-01), Moerschel
patent: 4919766 (1990-04-01), Kotowski et al.
patent: 4981567 (1991-01-01), Wolcott

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Method for testing encapsulation integrity 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 testing encapsulation integrity, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for testing encapsulation integrity will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-1507670

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.