Abstract: A method of underfilling a space between a semiconductor flip chip and a substrate to encapsulate a plurality of electrical connections with a viscous underfill material. The flip chip is mounted to the substrate with a plurality of electrical connections thereby forming a gap between opposed surfaces of the flip chip and substrate. The viscous underfill material is dispensed adjacent at least one edge of the flip chip. The flip chip and substrate are the rotated to move the underfill material into the gap under the influence of centrifugal force. The underfill material is cured after fully encapsulating the electrical connections.