Browse Prior Art Database

Coating Protection for Laser Cutting and Welding Operations

IP.com Disclosure Number: IPCOM000084829D
Original Publication Date: 1976-Jan-01
Included in the Prior Art Database: 2005-Mar-02
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

Rosenbaum, SB: AUTHOR [+2]

Abstract

In the more complex modules for integrated circuit semiconductor devices, it frequently becomes necessary to sever printed-circuit stripes on the surface of the module to make engineering changes, or modify or repair the circuitry. This severing and also welding operation can be achieved with a laser.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 1

Coating Protection for Laser Cutting and Welding Operations

In the more complex modules for integrated circuit semiconductor devices, it frequently becomes necessary to sever printed-circuit stripes on the surface of the module to make engineering changes, or modify or repair the circuitry. This severing and also welding operation can be achieved with a laser.

In this process, a coating of POLYOX*, a thermoplastic water soluble series of high-molecular weight, crystalline ethylene oxide polymers, are applied on the surface of the module as an aqueous solution, particularly over the site to be deleted or welded. Upon drying, the material forms a transparent or transluscent film being dependent on polymer concentration

When the laser is applied to the stripe to cut or weld, the film performs the following functions: (1) performs as an optical window to cause the laser beam to produce a dimensionally predictable deletion; (2) serves to normalize the variations in plating thicknesses to make possible deletions at fixed settings; (3) significantly reduces edge buildup at the deletions; (4) vaporizes when exposed to the laser beam so that there is no carbonaceous residue; and (5) facilitates the removal of the spattered material. In addition, the POLYOX coating is advantageous for wafer dicing to eliminate edge buildup and spattering. * Trademark of Union Carbide Corporation.

1