Electrical interconnections for semiconductor devices and methods for forming the same

Abstract

An electrical interconnection includes a wire loop having a first end bonded to a first bonding site using a first bonding portion, and a second end bonded to a second bonding site using a second bonding portion. The second bonding portion includes a folded portion having a wire that extends from the second end of the wire loop and is folded on the second bonding site. The folded portion includes a first folded portion connected to the second end of the wire loop and extending toward the first bonding site, a second folded portion provided on the first folded portion, and a tail protruding from a portion of the second folded portion. An interface is formed between the first and second folded portions. A top surface of the second folded portion includes an inclined surface recessed toward the first folded portion.

What is claimed is: 
     
         1 . An electrical interconnection for a semiconductor device, the electrical interconnection comprising:
 a wire loop having: a first end bonded to a first bonding site using a first bonding portion; and a second end bonded to a second bonding site using a second bonding portion,   wherein the second bonding portion comprises: a folded portion having a wire that extends from the second end of the wire loop and is folded on the second bonding site,   wherein the folded portion comprises:   a first folded portion connected to the second end of the wire loop and extending toward the first bonding site;   a second folded portion extending from the first folded portion and provided on the first folded portion; and   a tail end protruding from an end portion of the second folded portion,   wherein a bottom surface of the second folded portion is in contact with the first folded portion to form an interface therebetween, and   wherein a top surface of the second folded portion includes an inclined surface recessed toward the first folded portion.   
     
     
         2 . The electrical interconnection of  claim 1 , wherein the first folded portion comprises:
 a first end connected to the second end of the wire loop; and   a second end being opposite to the first end of the first folded portion and facing the first end of the wire loop,   wherein the first folded portion extends from the first end of the first folded portion to the second end of the first folded portion along a surface of the second bonding site.   
     
     
         3 . The electrical interconnection of  claim 2 , wherein the second folded portion comprises:
 a first end extending from the second end of the first folded portion; and   a second end being opposite to the first end of the second folded portion and facing the first end of the first folded portion,   wherein the first end of the second folded portion and the second end of the first folded portion are connected to each other to constitute a curve-shaped end portion.   
     
     
         4 . The electrical interconnection of  claim 3 , wherein the second end of the second folded portion is provided on the first end of the first folded portion, and
 wherein the interface is spaced apart from the second bonding site.   
     
     
         5 . The electrical interconnection of  claim 3 , wherein the second end of the second folded portion surrounds the first end of the first folded portion, and
 wherein the interface is connected to the second bonding site.   
     
     
         6 . The electrical interconnection of  claim 3 , wherein the tail end protrudes from the second end of the second folded portion in a direction away from the second bonding site. 
     
     
         7 . The electrical interconnection of  claim 1 , wherein the first folded portion extends from the second end of the wire loop toward the first end of the wire loop, and
 wherein the second folded portion extends from one end of the first folded portion toward the second end of the wire loop.   
     
     
         8 . The electrical interconnection of  claim 1 , wherein the first bonding portion comprises: a ball provided on the first bonding site and electrically connected to the first bonding site,
 wherein the first end of the wire loop is connected to the ball,   wherein the first end of the wire loop is connected to the second end of the wire loop by a wire.   
     
     
         9 . The electrical interconnection of  claim 1 , wherein the first bonding site and the second bonding site are disposed at substantially the same level or at different levels. 
     
     
         10 . The electrical interconnection of  claim 1 , wherein the first bonding portion ball-bonded to the first bonding site; and
 wherein the second bonding portion stitch-bonded to the second bonding site.   
     
     
         11 . A method of forming an electrical interconnection for a semiconductor device, the method comprising:
 performing a first bonding process using a bonding apparatus in which a wire is provided to connect the wire to a first bonding site;   providing the wire from the bonding apparatus to a second bonding site to form a wire loop between the first bonding site and the second bonding site; and   performing a second bonding process on the second bonding site using the bonding apparatus, to bond the wire loop to the second bonding site,   wherein the performing of the second bonding process comprises: moving the bonding apparatus along an overlapping trajectory on the second bonding site to form a folded portion on one end of the wire loop bonded to the second bonding site,   wherein the overlapping trajectory comprises:   a first trajectory along a first upward direction moving vertically away from the one end of the wire loop;   a second trajectory moving along a first downward diagonal direction beginning over the one end of the wire loop, moving horizontally toward the first bonding site, and becoming vertically closer to the second bonding site;   a third trajectory moving along a second upward direction vertically away from the one end of the wire loop; and   a fourth trajectory moving along a second downward diagonal direction beginning from nearer the first bonding site and moving horizontally toward and vertically closer to the second bonding site over the one end of the wire loop.   
     
     
         12 . The method of  claim 11 , wherein the performing of the second bonding process further comprises:
 lowering the bonding apparatus toward the second bonding site after moving the bonding apparatus along the fourth trajectory; and   raising the bonding apparatus from the second bonding site.   
     
     
         13 . The method of  claim 11 , wherein the folded portion comprises:
 a first folded portion connected to the one end of the wire loop and extending toward the first bonding site;   a second folded portion extending from the first folded portion and provided on the first folded portion; and   a tail end protruding from an end portion of the second folded portion,   wherein a bottom surface of the second folded portion is in contact with the first folded portion, and   wherein a top surface of the second folded portion includes an inclined surface recessed toward the first folded portion.   
     
     
         14 . The method of  claim 13 , wherein the first folded portion comprises:
 a first end connected to the one end of the wire loop; and   a second end being opposite to the first end of the first folded portion and facing an opposite end of the wire loop,   wherein the first folded portion extends from the first end of the first folded portion to the second end of the first folded portion along a surface of the second bonding site, and   wherein the opposite end of the wire loop is bonded to the first bonding site.   
     
     
         15 . The method of  claim 14 , wherein the second folded portion comprises:
 a first end extending from the second end of the first folded portion; and   a second end being opposite to the first end of the second folded portion and facing the first end of the first folded portion,   wherein the first end of the second folded portion and the second end of the first folded portion are connected to each other.   
     
     
         16 . An overlapping stitch bond for a semiconductor device having a wire loop comprising an end bonded to a bonding site using the overlapping stitch bond, the overlapping stitch bond comprising:
 a folded portion having a segment that extends from the end of the wire loop and is folded over the end of the wire loop on the bonding site.   
     
     
         17 . The overlapping stitch bond according to  claim 16 , wherein the folded portion comprises a double-folded portion having:
 a first folded portion connected to the end of the wire loop and extending over the end of the wire loop; and   a second folded portion extending from the first folded portion and provided on the first folded portion.   
     
     
         18 . The overlapping stitch bond according to  claim 17 , wherein an end of the second folded portion extends beyond the first folded portion and contacts the bonding site. 
     
     
         19 . The overlapping stitch bond according to  claim 17 , wherein the second folded portion does not contact the bonding site. 
     
     
         20 . The overlapping stitch bond according to  claim 19  further comprising a tail end, wherein the tail end is spaced apart from the bonding site.