Patent ID: 7597231
Filing Date: 2009-10-06
Classification: B23K,H01L

Abstract:
1. A bonding tool for bonding a fine wire to a substrate, said bonding tool comprising: a first substantially cylindrical portion having a first latitudinal cross-sectional average width and a length, wherein the first latitudinal cross-sectional average width is substantially constant along the length of the first substantially cylindrical portion; a second substantially cylindrical portion adjacent to the first substantially cylindrical portion and having a second latitudinal cross-sectional average width and a length, wherein the second latitudinal cross-sectional average width is substantially constant along the length of the second substantially cylindrical portion, and the second latitudinal cross-sectional average width is smaller than the first latitudinal cross-sectional average width; a third cylindrical portion adjacent to the second substantially cylindrical portion and having a third latitudinal cross-sectional average width and a length, wherein the third latitudinal cross-sectional average width is substantially constant along the length of the third cylindrical portion, and the third latitudinal cross-sectional average width is smaller than the second latitudinal cross-sectional average width; and a working tip portion having a length and a width adjacent to an end of the third substantially cylindrical portion and being tapered toward a tip of the working tip portion, said working tip portion having an annular chamfer at the tip thereof; wherein each of the first, second, and third substantially cylindrical portion defines therein a concentric capillary through which the fine wire runs; wherein the concentric capillary opens into the annular chamfer of the working tip; and wherein the first substantially cylindrical portion transitions to the second substantially cylindrical portion at a first discrete interval, and the second substantially cylindrical portion transitions to the third substantially cylindrical portion at a second discrete interval alone a length of the bonding tool.