US Patent 7843074 Underfill for light emitting device

A light emitting chip is disposed on a support surface. A plurality of bonding bumps are disposed in a gap between the light emitting chip and the support surface. The plurality of bonding bumps provide at least one electrical power input path to the light emitting chip. An underfill comprising underfill material is disposed in the gap between the light emitting chip and the support surface such that the underfill substantially fills the gap but does not form a fillet extending outside the gap over sidewalls of the light emitting chip. The underfill is configured to provide at least one of (i) mechanical support for the light emitting chip and (ii) a thermal conduction path from the light emitting chip to the support surface.