Browse Prior Art Database

High Density Bonding Tweezers

IP.com Disclosure Number: IPCOM000093520D
Original Publication Date: 1967-Oct-01
Included in the Prior Art Database: 2005-Mar-06
Document File: 2 page(s) / 60K

Publishing Venue

IBM

Related People

Steranko, JJ: AUTHOR

Abstract

This device positions a wire for bonding to a circuit board in situations where a large number of other wires tend to obscure the point. Surface 1 has a large number of pads 2 which are interconnected by discrete wires 3. Wires 3 are fixed to pads 2 by ultrasonic bonding head 4. Where high-density wiring is used to reduce the size of the finished circuit, there can be many layers of wires 3. These wires tend to obscure the pad to which a connection is to be made, making it difficult for bonding head to reach the pad without damage to the wires already in place.

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 55% of the total text.

Page 1 of 2

High Density Bonding Tweezers

This device positions a wire for bonding to a circuit board in situations where a large number of other wires tend to obscure the point. Surface 1 has a large number of pads 2 which are interconnected by discrete wires 3. Wires 3 are fixed to pads 2 by ultrasonic bonding head 4. Where high-density wiring is used to reduce the size of the finished circuit, there can be many layers of wires 3. These wires tend to obscure the pad to which a connection is to be made, making it difficult for bonding head to reach the pad without damage to the wires already in place.

To allow head 4 to penetrate the multilayer maze of wire, a sheath in the form of tweezers 5 and 6 serves to cover head 4 as it probes toward the selected contact area. Assuming that one end of an interconnecting wire 7 is already bonded as shown in drawing A, head 4 is raised slightly with respect to tweezers 5 and 6. This allows tweezers 5 and 6 to accommodate head 4 and close, as in drawing B. Notches 8 and 9 in the tweezers combine in the closed position to provide slot 10 for wire 7. Slot 10 allows head 4 to move laterally across the workpiece and still maintain the wire parallel to the bonding groove.

The wire should be stressed sufficiently while traveling to the second point to maintain the set in the wire. This insures contact between the welder and wire after the tweezer opens and the welder travels downward. A positive wire holder can be incorporated in the device b...