Nanowire sized opto-electronic structure and method for modifying selected portions of same
View Patent ↗A LED structure includes a support and a plurality of nanowires located on the support, where each nanowire includes a tip and a sidewall. A method of making the LED structure includes reducing or eliminating the conductivity of the tips of the nanowires compared to the conductivity of the sidewalls during or after creation of the nanowires.
1. A method of making a LED structure that comprises a support and a plurality of multilayer nanowires located on the support, wherein each nanowire comprises a tip and a sidewall, wherein the method comprises depositing a GaN layer of the nanowires by MOCVD using a carrier gas that comprises H 2 to reduce or eliminate a conductivity of the tips of the nanowires compared to the conductivity of the sidewalls during creation of the nanowires.
2. The method of claim 1 , wherein the nanowires comprise a multilayer structure and the GaN layer of the nanowires is formed using a carrier gas that comprises the H 2 and an inert MOCVD carrier gas.
3. The method of claim 2 , wherein the H 2 in the carrier gas is provided at 500 sccm or less.
4. The method of claim 1 , wherein the GaN layer of the nanowires comprises a GaN barrier layer for an active region of the LED structure.
5. The method of claim 4 , wherein the active region comprises an InGaN light emitting layer.
6. The method of claim 5 , wherein the GaN barrier layer is deposited by the MOCVD on the InGaN light emitting layer.
7. The method of claim 5 , wherein the InGaN light emitting layer is selectively deposited on a m-plane of the nanowires but not on a p-plane of the nanowires.
8. The method of claim 5 , wherein the InGaN light emitting layer is deposited over a GaN core of the nanowires by MOCVD using a carrier gas that does not contain H 2 .
9. The method of claim 5 , wherein the InGaN light emitting layer is etched on a p-plane of the nanowires during deposition of the GaN barrier layer by the MOCVD using the carrier gas that comprises H 2 .
10. The method of claim 5 , wherein deposition of the GaN barrier layer by the MOCVD using the carrier gas that comprises H 2 reduces a growth rate of the active region on a p-plane of the nanowire without reducing the growth rate of the active region on a m-plane of the nanowire.
11. The method of claim 1 , wherein a conductivity of the tip is reduced by at least one order of magnitude by using the carrier gas that comprises H 2 compared to the conductivity of the tip deposited without using the carrier gas that comprises H 2 .