04894115 is referenced by 155 patents and cites 4 patents.

The surface of a polymer dielectric layer is scanned repeatedly with a high energy continuous wave laser in a pattern to create via holes of desired size, shape and depth. This is followed by a short plasma etch. The via holes are produced at commercial production rates under direct computer control without use of masks and without damage to conductor material underlying the dielectric layer. A two-step technique usable to form a large hole to a partial depth in the dielectric layer and several smaller diameter holes within the large hole through the remainder of the dielectric layer depth allows formation of a large number of holes in a given area of a thick dielectric layer.

Title
Laser beam scanning method for forming via holes in polymer materials
Application Number
7/310149
Publication Number
4894115
Application Date
February 14, 1989
Publication Date
January 16, 1990
Inventor
Kenneth B Welles II
Scotia
NY, US
Robert J Wojnarowski
Ballston Lake
NY, US
Charles W Eichelberger
Schenectady
NY, US
Agent
James C Davis Jr
Marvin Snyder
Assignee
General Electric Company
NY, US
IPC
C03C 25/06
C03C 15/00
B29C 37/00
B44C 1/22
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