| abstract |
An assembly of a semiconductor chip having pads to a substrate having pads aligned to receive the semiconductor chip is provided, whereby at least one of the semiconductor chip pads and substrate pads include solder bumps. The solder bumps are deformed against the substrate pads and the semiconductor chip pads, whereby an underfill material is applied to fill the gap between the semiconductor chip and substrate. The underfill material does not penetrate between the deformed solder bumps, the semiconductor chip pads, and the substrate pads. At least one of the solder bumps have not been melted or reflowed to make a metallurgical bond between the semiconductor chip pads and the substrate pads, and at least another one of the solder bumps have been melted or reflowed to make a metallurgical bond between the semiconductor chip pads and the substrate pads. |