Methods for growing light emitting devices under ultra-violet illumination
Described herein are methods for growing light emitting devices under ultra-violet (UV) illumination. A method includes growing a III-nitride n-type layer over a III-nitride p-type layer under UV illumination. Another method includes growing a light emitting device structure on a growth substrate and growing a tunnel junction on the light emitting device structure, where certain layers are grown under UV illumination. Another method includes forming a III-nitride tunnel junction n-type layer over the III-nitride p-type layer to form a tunnel junction light emitting diode. A surface of the III-nitride tunnel junction n-type layer is done under illumination during an initial period and a remainder of the formation is completed absent illumination. The UV light has photon energy higher than the III-nitride p-type layer's band gap energy. The UV illumination inhibits formation of Mg—H complexes within the III-nitride p-type layer resulting from hydrogen present in a deposition chamber.
1. A method for forming a light emitting diode (LED), the method comprising:
epitaxially growing a III-nitride p-type layer having a band gap energy;
epitaxially growing a first portion of a non p-type layer over the III-nitride p-type layer under illumination by light having a photon energy higher than the band gap energy of the III-nitride p-type layer; and
epitaxially growing a second portion of the non p-type layer absent light illumination.
2. The method of claim 1 , wherein the light is provided through a window in a deposition chamber.
3. The method of claim 2 , wherein the deposition chamber is a MOCVD chamber.
4. The method of claim 1 , wherein the light is one of an ultraviolet light and a higher energy light.
5. The method of claim 1 , wherein the non p-type layer is an active layer.
6. The method of claim 1 , wherein the non p-type layer is a III-nitride n-type layer.
7. The method of claim 1 , wherein the III-nitride p-type layer is a tunnel junction III-nitride p-type layer and the non p-type layer is a III-nitride tunnel junction n-type layer.
8. The method of claim 7 , wherein epitaxially growing the III-nitride p-type layer further comprises:
illuminating the tunnel junction III-nitride p-type layer with light having a photon energy higher than the band gap energy of the III-nitride p-type layer during a growth period of the tunnel junction III-nitride p-type layer.
9. The method of claim 8 , further comprising:
annealing the tunnel junction III-nitride p-type layer.