The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 27, 1983
Filed:
Oct. 19, 1981
Applicant:
Inventor:
Howard A Froot, Hartsdale, NY (US);
Assignee:
International Business Machines Corporation, Armonk, NY (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
C09K / ;
U.S. Cl.
CPC ...
264 21 ; 264 22 ; 264 61 ; 264 63 ; 264 67 ;
Abstract
To detect residual glass, such as appears at semiconductor chip pads and via holes during the fabrication of alumina/glass ceramic substrates that are used as supports for the semiconductor devices, the glass used for forming the ceramic substrates is doped with a rare earth oxide. During the manufacturing process, the ceramic structures are irradiated after firing with radiation of wavelengths in the range 350-500 nanometers to induce the glass to fluoresce, thereby revealing the residual glass on the surface of the metallic interconnector pads. If residual glass is present, the parts are reworked, or scrapped if necessa