Browse Prior Art Database

Diffusion Bonding

IP.com Disclosure Number: IPCOM000040823D
Original Publication Date: 1987-Jan-01
Included in the Prior Art Database: 2005-Feb-02
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

Andreshak, J: AUTHOR [+2]

Abstract

Lead attachment is accomplished simply and reliably by diffusion bonding of copper to copper without need of solder.

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

Page 1 of 1

Diffusion Bonding

Lead attachment is accomplished simply and reliably by diffusion bonding of copper to copper without need of solder.

In the figure, component 1 having copper leads 2 is positioned by pick-and- place tool 3 so that leads 2 are placed on corresponding copper pads 4 of circuit board 5. Tool 3 carries multiple pressure tips 6, each coincident with a lead 2. The tips are suitably heated by pulsing or laser to above 0.5 Tm where Tm is the absolute melting temperature of the metal. For copper, 0.5 Tm is approximately 400oC. The leads are compressed on their mating pads by tips 6 at approximately the yield strength of copper or between 5,000 and 10,000 psi. For a contact diameter of 0.006 in. the tip pressure is about 100 grams. This technique lends itself to bonding simultaneously on opposite sides of a board and to a wide range of lead spacings.

Disclosed anonymously

1