Accession Number : ADD006007

Title :   Ultrasonic Wire-Bonding Apparatus for Negating Torsional Forces Present in a Transversely-Driven Wire-Bonding Tool.

Descriptive Note : Patent Application,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Salzer,Thomas E ; Cheriff,Frank J ; Zaffini,James A

Report Date : 26 Feb 1979

Pagination or Media Count : 14

Abstract : Ultrasonic bonding is used to electrically couple terminal and other wires to an active semiconductor chip. Conventionally, a magnetostrictive transducer having a longitudinal driving mode causes a bonding tool to vibrate while holding the wire in intimate contact with the chip. However, bond quality has not been consistently good due primarily to certain torsional moments of forces present in the longitudinal driving mode. This problem can be avoided by modifying the conventional manner in which the bonding tool is coupled to the transducer. Specifically, the tool and its clamping surfaces are specially-shaped to provide a Vee-block clamping arrangement in which the tool is held in a symetric two-point line contact with the clamping pressure being supplied by a set-screw engaging the tool midway of the two points. (Author)

Descriptors :   *Patent applications, *Lead wires, *Bonding, *Ultrasonic welding, Laboratory equipment, Torsion, Tools, Electric terminals, Coupling(Interaction), Semiconductors, Chips(Electronics), Transducers, Magnetostrictive elements, Vibration

Subject Categories : Electrical and Electronic Equipment
      Mfg & Industrial Eng & Control of Product Sys

Distribution Statement : APPROVED FOR PUBLIC RELEASE