| 摘要 |
PURPOSE:To inexpensively manufacture a high density mounting flip chip by bonding a predetermined quantity of solder balls on the electrode pad of a wafer by an ultrasonic wire bonder having a hydrogen flame torch, and then wetting back the balls in a reflow furnace. CONSTITUTION:When a wafer 1 is positioned on a holder 22 from a loader 7, a bonding arm 11 is operated with the signal of a controller 20, and solder balls 18 formed at the lower end of a capillary 14 are bonded on an aluminum electrode pad 4. That is, the capillary 14 is secured to the end of the arm 11 to which an ultrasonic wave oscillator 13 is attached at its base end, and the end of a solder wire 15 is heated and melted by a hydrogen flame torch 17 provided near it, thereby forming solder balls 18. Then, the wafer is covered with flux, conveyed to a reflow furnace 23 disposed adjacent to a bonding head 9, and wetted back in a nonoxidative or reducing atmosphere. Then, the balls 18 are melted to form semispherical solder bumps 24 on the pad 4. |
