Patent ID: 8143155

Claim:
A wire-bonding method of connecting between a first bonding point and a second bonding point by a wire, the method comprising the steps of: a first bonding step of bonding an initial ball formed at a tip end of the wire to the first bonding point using a capillary, thereby forming a pressure-bonded ball and a ball neck; a ball neck treading step, after the first bonding step, of moving the capillary upward, away from the second bonding point, and immediately downward into contact with the ball neck, thereby treading on a portion of the ball neck facing toward the second bonding point until a surface of the portion is made into a flat surface with a first face portion facing toward the second bonding point of the capillary; a pressing step, after the ball neck treading step, of moving the capillary upward and then toward the second bonding point until a second face portion facing away from the second bonding point of the capillary is positioned above the ball neck such that the wire is folded back toward the second bonding point, and subsequently moving the capillary downward, thereby pressing a surface of the wire that has been folded back on the portion of the ball neck that has been trodden on and flattened with the second face portion facing away from the second bonding point of the capillary while bonding and contacting the surface of the wire to the ball neck; an oblique-upward raising step, after the pressing step, of moving the capillary obliquely upward toward the second bonding point; and a second bonding step, after the oblique-upward raising step, of moving the capillary upward and then toward the second bonding point, and bonding the wire to the second bonding point by pressure-bonding.