Systems and methods for producing white-light emitting diodes

1. A method for fabricating a phosphor n-GaN up light-emitting diode (LED) wafer, comprising:

providing a carrier substrate;

depositing an n-GaN layer above the carrier substrate;

depositing active layers above the n-GaN portion;

depositing a p-GaN layer above the active layers;

depositing one or more metal layers;

applying a masking layer;

etching the metal, the p-GaN layer, the active layers, and the n-GaN layer;

removing the masking layer;

depositing a passivation layer;

removing a portion of the passivation layer on top of the p-GaN layer to expose the metal,

depositing one or more layers;

depositing a metal substrate;

removing the carrier substrate to expose the n-GaN surface; and

applying a phosphor layer above the n-GaN surface.

2. The method of claim 1 , wherein the phosphor n-GaN up LED wafer is substantially smooth and flat.

3. The method of claim 2 , wherein the phosphor n-GaN up LED wafer has a surface roughness less than 10000 angstrom before the phosphor layer is applied.

4. The method of claim 1 , wherein the carrier substrate is sapphire.

5. The method of claim 1 , wherein the metal substrate is deposited using one of: electro-chemical plating, electroless chemical plating, sputtering, chemical vapor deposition, e-beam evaporation, thermal spray.

6. The method of claim 1 , wherein the metal substrate is a metal or metal alloy comprising one of Copper, nickel, aluminum.

7. The method of claim 1 , wherein the carrier substrate is removed using one of: laser lift-off (LLO), wet etching, chemical mechanical polish.

8. The method of claim 1 , wherein the p-contact comprises a light reflector.

9. The method of claim 1 , comprising a bond pad coupled to the phosphor layer.

10. The method of claim 1 , wherein the phosphor layer applied at the wafer level is coupled to n-GaN surface of the n-side up vertical LED.