Robert A Curtis

US Patent:

50873962, Feb 11, 1992

Filed:

Feb 21, 1991

Appl. No.:

7/662314

Inventors:

Gordon O. Zablotny - San Diego CA
Robert D. Curtis - Encinitas CA
James W. Horner - San Diego CA
Ronald A. Norell - Carlsbad CA

Assignee:

Unisys Corporation - Blue Bell PA

International Classification:

B29C 3702

US Classification:

264 25

Abstract:

Via holes in a thin planar layer of unfired ceramic which consists essentially of a mixture of an inorganic nonmetallic powder having a high melting temperature and a binder having a lower vaporizing temperature, are formed by the steps of: directing a laser beam, in a sequence, at certain locations on the layer where the via holes are to be formed; controlling the power density in the directed laser beam to a low level at which the binder vaporizes at each of the locations while the powder stays unsintered and unmelted; and removing from the directed laser beam during the above steps, both the vaporized binder and the unbound powder which remains where the binder vaporizes. Preferably, the vaporizing temperature of the binder and the melting temperature of the binder and the melting temperature of the powder are selected such that they differ by at least 200. degree. C. ; the power density of the laser is controlled to be between 5 kW/cm. sup. 2 and 75 kW/cm. sup.

Address:

2902 E Ksel Dr, Sandy, UT 84092

VIN:

1HGCM553X7A086165

Make:

HONDA

Model:

ACCORD SDN

Year:

2007