引張り矯正による金極細線の直進性改善

抄録

With the recent advances in the semiconductor industry, the demand for gold, copper and aluminum bonding wires has been increasing. Wire diameter has been decreasing due to the market demand for small and highly functional products. Also, a high degree of wire straightness is required to prevent short-circuit defects caused by contact between looped wires. Although methods of improving the straightness of superfine wires by tensile straightening have been examined, the number of such studies is limited and the mechanism of improving the straightness of wires has not yet been clarified. In this study, tensile straightening was carried out for superfine gold wires to examine the change in wire straightness under various conditions. We proposed a residual stress measurement method that allows us to quantitatively measure the residual stress in a wire specimen, which obtained by removing a part of the wire using a focused ion beam (FIB). We also demonstrated the relationship between straightness and residual stress. Furthermore, the effect of tensile strain on the crystalline structure was examined to clarify the effect of the tensile strain on the straightness of the wire and the crystal orientation rate.