Effect of Ca Content on Mechanical Properties of 4N Gold Wire for Quad Flat Nolead (QFN) Stacked Die Package

Abstract:

This paper discusses the effect of two similar gold wire (wire A and wire B) used mainly as a wire bonding material for Quad Flat Nolead (QFN) package. Both wires with diameter of 25.4 μm were bonded using automatic wire bonder by maintaining the temperature at 200°C. The effect of trace elements on the mechanical properties of 4N gold wire has not been widely investigated for some years despite the important of wire-bonding and the move towards fine pitch applications. Due to the element analysis, atomic percentage of Ca in wire B is higher than wire A. Pull strength increase with the increasing of the trace element. The higher pull strength of wire B could improve the yield strength, elastic modulus and recrytallization temperature.

• Periodical: Advanced Materials Research (Volumes 97-101)
• Pages: 36-39
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.97-101.36
• Online since: March 2010
• Authors: Azman Jalar, Saidatul Azura Radzi, Muhammad Azmi Abd Hamid
• Keywords: Ball Bonding, QFN Packaging, Ultrasonic (USG) Current, Wire Bonding

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