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:
Mar. 22, 1994
Filed:
Apr. 28, 1992
Sung K Kang, Chappaqua, NY (US);
Sampath Purushothaman, Yorktown Heights, NY (US);
John J Ritsko, Mount Kisco, NY (US);
Jane M Shaw, Ridgefield, CT (US);
Subhash L Shinde, Croton-on-Hudson, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
Methods of fabricating powders of metal particles containing grain growth control additives are described. A powder, metal particles, e.g., copper particles, are mixed with a powder of additive particles, e.g., alumina particles. The mixture is milled in a high energy ball mill to provide metal particles having substantially uniformly distributed therein of additive particles. The ball milled powder contains elongated high aspect ratio particles. The high aspect ratio particles are reduced in size by jet impact milling. The jet impact milled powder can be used to form a conductor forming paste in the fabrication of a metallized ceramic substrate for semiconductor chip packaging application. The jet impact milled powder has particles of sufficiently small in size to fill vias between metallization layers in the green ceramic precursor to the ceramic substrate. During sintering of the combination of ceramic precursor and conductor forming paste, the grain growth control additive results in a substantially void free via filled with metal having a fine grain morphology.