| 摘要 |
PURPOSE:To prevent the damage to an Si chip surface at the time of ball bonding at high speed, by setting the contents of S and C components as unavoidable impurities at specified values respectively, and making the total content of the unavoidable impurities less than or equal to 5ppm. CONSTITUTION:The contents of S and C components as unavoidable impurities are set as follows; S is less than or equal to 0.5ppm, and C is less than or equal to 1ppm. The total content of unavoidoble impurities is made less than or rqual to 5ppm. As the result, the hardness of a ball part formed at the tip of a wire becomes relatively low, and the change of hardness of the ball part before and after the ball bonding becomes small. Thereby, on the occasion of a high speed ball bonding, the damage to an Si chip surface is reduced. |
