Light emitting diode containing oxidized metal contacts
A method of forming a light emitting device includes forming a semiconductor light emitting diode, forming a metal layer stack including a first metal layer and a second metal layer on the light emitting diode, and oxidizing the metal layer stack to form transparent conductive layer including at least one conductive metal oxide.
1. A direct view display device, comprising:
a first light emitting diode bonded to a backplane; and
a second light emitting diode bonded to the backplane;
wherein:
the first light emitting diode is configured to emit light of a first peak wavelength and comprises a transparent conductive layer located between a first doped semiconductor layer and an aluminum or silver reflector layer; and
the second light emitting diode is configured to emit light of a second peak wavelength longer than the first peak wavelength and comprises a gold reflector layer directly contacting a second doped semiconductor layer.
2. The direct view display device of claim 1 , wherein:
the transparent conductive layer in the first light emitting diode comprises at least one of gold or nickel oxide layers having a thickness in a range from 1 nm to 10 nm;
the gold reflector layer of the second light emitting diode has a thickness of at least 100 nm;
the first light emitting diode is configured to emit blue or green light; and
the second light emitting diode is configured to emit red light.
3. The direct view display device of claim 2 , wherein:
the transparent conductive layer contacts a first gold doped semiconductor region in the first doped semiconductor layer in the first light emitting diode;
the gold reflector layer contacts a second gold doped semiconductor region in the second doped semiconductor layer in the second light emitting diode; and
the gold reflector is configured to shift a center of emission spectrum of light emitted by the second light emitted diode to a longer wavelength.
4. The direct view display device of claim 1 , wherein the transparent conductive layer contacts the aluminum or silver reflector layer.
5. The direct view display device of claim 1 , wherein the transparent conductive layer comprises a transparent conductive metal oxide material.
6. The direct view display device of claim 1 , wherein the first light emitting diode comprises a first gold doped region in the first doped semiconductor layer, and wherein the gold doped region contacts the transparent conductive layer.
7. The direct view display device of claim 6 , wherein the first gold doped region comprises a gold doped III-nitride semiconductor region.
8. The direct view display device of claim 6 , wherein the second light emitting diode comprises a second gold doped region in the second doped semiconductor layer, and wherein the gold doped region contacts the gold reflector layer.
9. The direct view display device of claim 1 , wherein the gold reflector layer comprises gold at an atomic percentage in a range from 90% to 100%.
10. The direct view display device of claim 1 , wherein:
the first light emitting diode is configured to emit blue or green light;
the second light emitting diode is configured to emit red light; and
the gold reflector layer induces red shift of a center of an emission spectrum of light that is emitted from an active region of the second light emitting diode.
11. The direct view display device of claim 1 , wherein:
the first and second light emitting diodes comprise III-V semiconductor, bottom emitting, vertical light emitting diodes;
the transparent conductive layer and the aluminum or silver reflector are formed on the first doped semiconductor layer; and
the gold reflector layer is formed on the second doped semiconductor layer.