| 摘要 |
PURPOSE:To provide a semiconductor device having an extremely high durability against heat cycles or against leaving it at a high temperature, by a method in which after an end of a copper based wire is melted to form a ball, the ball is reduced in a reducing gas atmosphere over a predetermined temperature and is then joined to an electrode pad. CONSTITUTION:A copper based wire 5 is cut at the outlet of the capillary 4 with gas flame poured from an oxygen-hydrogen tourch 7 to form a ball 5a at the outlet the capillary 4. Next, the capillary 4 is lowered toward an electrode pad 2A of a semiconductor chip 2 so that the copper based wire 5 can be joined to the electrode pad 2A. In this case, when the ball is formed, the ball temperature is raised over a melting temperature and the semiconductor chip 2 is heated at a desired temperature, for example 300 deg.C, by a heater 3. Since reducing gas 8 is being supplied in the space belot the movable cover 6, the surface of the ball 5a with a temperature above 200 deg.C being placed in the reducing gas 8 is in a reduced state. |
