Papers by Keyword: Ball Bonding

Abstract: Copper wire bonding has obtained prevalent owning to its economic advantage and superior electrical property. However, the replacement of gold wire with copper wire introduces hardness related issues as copper is much harder than gold. This article reports investigations of the process optimization of ball bonding for 1.8mil copper wire. The results showed that the suitable ranges of the three key parameters were: contact force was 100~120gf, bond time was 15~25ms, and bond power was 100~110dac. When the input energy was too low, it was hard to get effective bonding. However, excessive input energy would cause chip crater and serious extrusion of metallization layer.

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.