Browse Prior Art Database

Laser Etching of Core Loading Matrix Adhesives

IP.com Disclosure Number: IPCOM000088676D
Original Publication Date: 1977-Jul-01
Included in the Prior Art Database: 2005-Mar-04
Document File: 2 page(s) / 62K

Publishing Venue

IBM

Related People

Cooper, JT: AUTHOR [+4]

Abstract

The illustration shows top and sectional views of a laminated support 1 for holding magnetic cores in a core memory array. Magnetic cores are held in the slots 3. Metal layers 5, 6, 7, 8 are bonded together by an epoxy adhesive to form support 1. The layers contain openings which must be critically aligned to form the slots 3. The slot width of approximately .003 inch is tailored to receive magnetic cores .0025 inch thick.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 97% of the total text.

Page 1 of 2

Laser Etching of Core Loading Matrix Adhesives

The illustration shows top and sectional views of a laminated support 1 for holding magnetic cores in a core memory array. Magnetic cores are held in the slots 3. Metal layers 5, 6, 7, 8 are bonded together by an epoxy adhesive to form support 1. The layers contain openings which must be critically aligned to form the slots 3. The slot width of approximately .003 inch is tailored to receive magnetic cores .0025 inch thick.

During the bonding/laminating process, excess adhesive is squeezed out into the slots. This excess must be removed from the slots to make room for the cores. Removal by chemical etching poses a problem inasmuch as over-etching may degrade the adhesion bond between layers and under-etching must be followed by laborious manual removal of excess adhesive.

Laser etching is considerably more effective inasmuch as substantially all excess adhesive is removed without degradation of the adhesion bond. An infrared laser beam, such as that from a CO2 laser operating at 10.6 microns wavelength, is heavily absorbed by the adhesive in the slots and highly reflected by the surface of the (metal) laminate. The high absorption of laser energy results in rapid and complete vaporization of all excess adhesive in the slots.

Another advantage of laser etching is that the workpiece (support) is not contacted by chemicals or potential contaminants and, therefore, does not require cleansing after etching.

1

Page 2 of 2

2...