Method of manufacturing semiconductor device and wire bonding apparatus
View Patent ↗A terminal of a compact wire loop with a great strength of bonding is formed by a method including: a first folding step in which a tip end of a capillary is raised by a height of H 1 from a point 86 a where the center of the capillary is positioned during second bonding on a lead 74 to a point “p”, and then moved horizontally by a first distance of L 1 toward a pad 73 , and lowered to a point “r”; a second folding step in which the tip end of the capillary is raised from the point “r” to a height of H 2 and then moved horizontally toward the lead 74 by a second distance of L 2 ; and a third bonding step in which the center of the capillary is aligned with and then lowered to a point 87 a on the lead 74 adjacent to the point 86 a.
1. A method of manufacturing a semiconductor device having a wire loop to be connected to a first bonding point and a second bonding point with a capillary, the method comprising:
a first bonding step of bonding a wire to a first bonding point by means of a capillary;
a second bonding step of, after the first bonding step, bonding the wire to a second bonding point by means of the capillary in such a manner that the capillary is raised while feeding the wire out of the tip end of the capillary and subsequently looped to the second bonding point along a predetermined trajectory, and then the wire is bonded to the second bonding point, thereby forming a wire loop connecting to the first bonding point and the second bonding point;
a first trampling bonding step of, after the second bonding step, trampling the wire to the wire loop by means of the capillary in such a manner that the capillary is raised while feeding the wire out of the tip end of the capillary and subsequently moved toward the first bonding point by a first predetermined distance, and then the capillary is lowered to the wire loop to bond the wire fed out of the tip end of the capillary onto the wire loop and the portion where the wire has bonded to the second bonding point, thereby forming a first trampled portion while folding and trampling thereon;
a third folding step of, after the first trampling bonding step, folding the wire to the first trampled portion by means of the capillary in such a manner that the capillary is raised while further feeding the wire out of the tip end thereof and subsequently moved in a direction opposite to the first bonding point by a second predetermined distance, and then the capillary is lowered, thereby forming the wire further fed out of the tip end of the capillary into a third folded portion having a shape that follows the upper face on the first trampled portion; and
a second trampling bonding step of, after the third folding step, bonding the wire by means of the capillary in such a manner that the capillary is lowered to bond the wire to immediately adjacent to the bonded portion where the wire has bonded to the second bonding point, thereby bonding the wire thereon while causing the capillary to trample at least a portion of the third folded portion located at the second bonding point side with a face portion of the capillary located at the first bonding point side in such a manner as to be overlapped onto the first trampled portion.
2. The method of manufacturing a semiconductor device according to claim 1 , wherein
the first trampling bonding step is arranged such that the wire fed out of the tip end of the capillary is folded onto the wire loop and the portion where the wire has bonded to the second bonding point, and trampled until a portion of the surface thereof is made into a flat.
3. The method of manufacturing a semiconductor device according to claim 1 , wherein
the second trampling bonding step is arranged such that at least a portion of the third folded portion located at the second bonding point side is trampled onto the first trampled portion with the face portion located at the first bonding point side of the capillary until a portion of the surface thereof is made into a flat.