Au Alloy Bonding Wire

Abstract

Provided is a thin Au alloy bonding wire having desired strength, good bondability and stability over time, and improved circularity of a squashed ball and sphericity of a melted ball. The Au alloy bonding wire contains, in an Au alloy matrix containing 0.05 to 2 mass % in total of at least one selected from Pd and Pt of high purity in Au of high purity, as trace elements, 10 to 100 ppm by mass of Mg, 5 to 100 ppm by mass of Ce, and 5 to 100 ppm by mass of each of at least one selected from Be, Y, Gd, La, Eu and Si, the total content of Be, Y, Gd, La, Eu and Si being 5 to 100 ppm by mass, or as trace elements, Mg, Be, and at least one selected from Y, La, Eu and Si, or as trace elements, 10 to 100 ppm by mass of Mg, 5 to 30 ppm by mass of Si, 5 to 30 ppm by mass of Be, and 5 to 30 ppm by mass of at least one selected from Ca, Ce and Sn.

1 . An Au alloy bonding wire comprising an Au alloy in which trace elements are contained in an Au alloy matrix containing 0.05 to 2 mass % in total of at least one selected from Pd and Pt of high purity of at least 99.9 mass % in Au of high purity of at least 99.99 mass %; wherein said trace elements comprise 10 to 100 ppm by mass of Mg, 5 to 100 ppm by mass of Ce, and 5 to 100 ppm by mass of each at least one selected from Be, Y, Gd, La, Eu and Si, the total content of Be, Y, Gd, La, Eu and Si being 5 to 100 ppm by mass.  
     
     
         2 . An Au alloy bonding wire comprising an Au alloy in which trace elements are contained in an Au alloy matrix containing 0.05 to 2 mass % in total of at least one selected from Pd and Pt of high purity of at least 99.9 mass % in Au of high purity of at least 99.99 mass %; 
 wherein saidtrace elements comprise 10 to 100 ppm by mass of Mg, 5 to 100 ppm by mass of Be, and at least one selected from Y, La, Eu and Si, the content of each of Y, La, Eu and Si among the trace elements being 5 to 100 ppm by mass, and the total content of Y, La, Eu and Si being 100 ppm by mass or lower.    
     
     
         3 . An Au alloy bonding wire comprising an Au alloy in which trace elements are contained in an Au alloy matrix containing 0.05 to 2 mass % in total of at least one selected from Pd and Pt of high purity of at least 99.9 mass % in Au of high purity of at least 99.99 mass %; 
 wherein said trace elements comprise 10 to 100 ppm by mass of Mg, 5 to 30 ppm by mass of Si, 5 to 30 ppm by mass of Be, and 5 to 30 ppm by mass of either of Ca and Sn.    
     
     
         4 . An Au alloy bonding wire comprising an Au alloy in which trace elements are contained in an Au alloy matrix containing 0.05 to 2 mass % in total of at least one selected from Pd and Pt of high purity of at least 99.9 mass % in Au of high purity of at least 99.99 mass %; 
 wherein said trace elements comprise 10 to 100 ppm by mass of Mg, 5 to 30 ppm by mass of Si, 5 to 30 ppm by mass of Be, and 5 to 30 ppm by mass each of, and 10 to 60 ppm by mass in total of, two selected from Ca, Ce and Sn.    
     
     
         5 . An Au alloy bonding wire comprising an Au alloy in which trace elements are contained in an Au alloy matrix containing 0.05 to 2 mass % in total of at least one selected from Pd and Pt of high purity of at least 99.9 mass % in Au of high purity of at least 99.99 mass %; 
 wherein said trace elements comprise 10 to 100 ppm by mass of Mg, 5 to 30 ppm by mass of Si, 5 to 30 ppm by mass of Be, and 5 to 30 ppm by mass each of, and 15 to 90 ppm by mass in total of, all three of Ca, Ce and Sn.    
     
     
         6 . The Au alloy bonding wire according to any of claims  1  through  5 , wherein the total content of said trace elements is 100 ppm by mass or lower.  
     
     
         7 . The Au alloy bonding wire according to any of claims  1  through  5 , having a wire diameter of 23 μm or smaller.