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:
May. 30, 1989
Filed:
Nov. 26, 1986
Applicant:
Inventors:
Eric A Barringer, Waltham, MA (US);
Brian C Foster, Sutton, MA (US);
James D Hodge, Medway, MA (US);
Roger S Lind, Acton, MA (US);
Assignee:
Ceramics Process Systems Corporation, Cambridge, MA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B32B / ; C03C / ; C03C / ; B22F / ;
U.S. Cl.
CPC ...
428210 ; 428209 ; 428428 ; 428432 ; 428901 ; 501 15 ; 501 17 ; 501 32 ; 106-105 ;
Abstract
A tungsten paste suitable for co-sintering with 98+% alumina substrate can be produced by adding selected compositions of glass to the paste. Circuit packages produced in accordance with the present invention exhibit superior thermal conductivity, low shrinkage variability, and smoother and more homogeneous surface finish. A preferred embodiment of the invention utilizes a substrate comprising narrow size range alumina powder, thus yielding lower sintering temperature and further improvements in shrinkage variability and surface finish.