A light emitting device with a heat sink composed of two materials is provided. The device comprises: a light emitting material; and, a heat sink comprising: a first material configured to cool the light emitting material, the first material comprising a first coefficient of thermal expansion (CTE); and, a second material bonded to the first material at an interface there between, the second material comprising a second CTE lower than the first CTE, the light emitting material bonded to the first material but not the second material.