Wire bonding method

A wire bonding method comprising sequentially:

• forming a ball at the tip of a fine metal wire passing through a capillary tip;
• joining the ball by pressing the ball with the capillary tip against a first electrode;
• moving the capillary tip from the first electrode toward a second electrode while the fine metal wire is paid out through the capillary tip;
• clamping the fine metal wire with a first clamp and moving the first clamp and the capillary tip closer to the second electrode;
• releasing the first clamp from the fine metal wire;
• moving the capillary tip still closer to the second electrode;
• clamping the fine metal wire and the first clamp;
• moving the first clamp away from the capillary tip, thereby drawing an excess length of the fine metal wire protruding from the end of the capillary tip back into the capillary tip;
• clamping the fine metal wire with a second clamp located farther from the capillary tip than the first clamp;
• releasing the first clamp from the fine metal wire;
• moving the capillary tip toward the second electrode and joining the fine metal wire at the end of the capillary tip to the second electrode by pressing the capillary tip against the second electrode;
• and
• releasing the second clamp form the fine metal wire.