Patent ID: 8471280

Claim:
A light emitting device comprising: a light emitting diode (LED) die, the LED die having a bottom surface; a submount on which the LED die is mounted, there being a gap between the LED die and the submount; the LED die having a plurality of metal posts electrically connected to the bottom surface, there being substantially transparent areas between the metal posts along a bottom surface of the LED die so that light emitted downward by the LED die passes between the metal posts; and a substantially reflective underfill material filling voids between the bottom surface of the LED die and the submount, the underfill material comprising silicone and a reflective powder having a thermal conductivity greater than 20 W/m/K, the underfill material reflecting light from the LED die generally upward and conducting heat between the LED die and the submount wherein the underfill material further comprises silicone infused with TiO2, wherein the TiO2 comprises more than about 5%, by weight, of the underfill material.