| 摘要 |
An improved means and method for forming leads to a power device is provided by use of a one-piece leadframe (12,30) on which the die (16) is mounted and a separate connecting clip (40) between the leadframe (12,30)and the bonding pad (22) on the semiconductor die (16). The leadframe (12,30) has an alignment dimple or groove (32) for receiving a mating alignment feature (42) on one end of the connecting clip (40). The other end (46) of the connecting clip (40) is located over the bonding pad (22) on the die (16). Solder (2) is placed between die (16)and the leadframe (12,30) and between the connecting clip (40) and the bonding pad (22) and between the mating alignment surfaces (44,34) on the clip (40) and leadframe (30). When the solder is liquid during assembly the die (16) and clip (40) float thereon and automatically align by surface tension so that the die (16) is centrally located on the die flag (13), the connection point (48) on the clip (40) is centered on the bonding pad (22) and the mating alignment surfaces (44,34) on the clip (40) and leadframe (30) are engaged. The self-aligning process is dominated by the mating alignment regions (42,32) on the connecting clip (40) and leadframe (30) which have a larger area and solder wetted periphery than the other regions being soldered. |
