Methods for packaging light emitting devices and related microelectronic devices

Abstract

A method for forming a light emitting device includes providing a light emitting diode (LED) configured to emit light of a first color and providing a plurality of semi-spherical lenses made of a silicone material that contains no phosphor material. Each of the lenses has a layer of phosphor material attached thereto. The method also includes testing the plurality of lenses to select a subset of lenses that converts light of the first color to light of a second color. The method further includes forming the light emitting device using the LED, one of the selected subset of lenses, and a heat conductive substrate. In an embodiment, after the testing of the plurality of lenses, one of the selected subset of lenses is disposed overlying the LED. In another embodiment, the testing of the plurality of lenses is conducted with a light source other than the LED.

1 . A light emitting device, comprising
 a heat conductive substrate;   at least one semiconductor light emitting diode (LED); and   an encapsulant overlying the at least one LED, the encapsulant comprising a substantially uniform layer of wavelength-converting material,   wherein the encapsulant is preformed and pre-characterized for optical properties prior to being disposed overlying the LED.   
     
     
         2 . The light emitting device of  claim 1 , wherein the wavelength-converting material comprises LED phosphor. 
     
     
         3 . The light emitting device of  claim 1 , wherein the encapsulant comprises LED lens. 
     
     
         4 . The light emitting device of  claim 1 , wherein the heat conductive substrate comprises an electrical circuit for wiring connection. 
     
     
         5 . The light emitting device of  claim 1 , wherein the heat conductive substrate further comprises an integrated optical reflector being shaped with part of the heat conductive substrate. 
     
     
         6 . The light emitting device of  claim 1 , further comprising a bond-wire loop that does not exceed the very top surface of a circuit board on the heat conductive substrate. 
     
     
         7 . The light emitting device of  claim 1 , wherein the encapsulant comprises a semi-spherical surface and a flat surface, and the layer of light-conversion material is attached to the flat surface. 
     
     
         8 . The light emitting device of  claim 1 , wherein the encapsulant comprises a semi-spherical surface and a flat surface, and the layer of light-conversion material is attached to the semi-spherical surface. 
     
     
         9 . The light emitting device of  claim 1 , wherein the encapsulant comprises a convex surface and a concave surface, and the layer of light-conversion material is attached to the convex surface. 
     
     
         10 . The light emitting device of  claim 1 , wherein the encapsulant comprises a convex surface and a concave surface, and the layer of light-conversion material is attached to the concave surface.