| 摘要 |
PURPOSE:To form a bump in a short time by a method wherein an external force is applied to a wire so as to leave a connected part on an object and cut and separate the rest of the wire to form a bump material, which is pressed and formed into a shape with a flat upper face of a prescribed height. CONSTITUTION:A ball 5 is formed on the tip of a wire through a spark by applying a high voltage between the wire 1 and an electric torch rod 4 through the rod 4. Then, loosening a clamp 2, a capillary 3 is made to be pulled down to the prescribed position on an object such as a wafer and the like so as to bond the ball 5. Next, tightening the clamp 2, the capillary 3 is made to be pulled up above the ball 5 1-3 times as far as the length of a diameter of the wire 5 and the wire 5 is made to be swayed right and left with the clamp 2, so that cracks or the like takes place at the joint between the ball section and the wire section. And, the wire is pulled up through the clamp 2 so as to cut off the ball section from the wire section. Thereafter, the clamp 2 is made to be pulled down and the wire 1 is made to extend from the tip of the capillary 3, and this process is continuously performed in a repeating way. And thus, a ball bump 9 is formed, of which upper face is flattened through a ball forming plate 8. |
