Light emitting diode device with tunable emission
Described at light emitting diode (LED) devices emitting different colors on the same wafer, which facilitates their integration with close packing density (not requiring transfer of devices from two different wafers to a third substrate module). The LED devices and driving methods allow light of different colors and similar luminance levels to be emitted for given input current.
1. A light emitting diode (LED) device comprising:
a mesa array comprising a first mesa and a second mesa separated by a trench, the first mesa and the second mesa comprising semiconductor layers, the semiconductor layers including an n-type layer, an active layer, and a p-type layer, the trench having at least one side wall and extending to the n-type layer, the first mesa having a first width and the second mesa having a second width, the first width greater than the second width;
an anode contact comprising a first anode region on a top surface of the first mesa and a second anode region on a top surface of the second mesa, the first anode region larger than the second anode region; and
a cathode contact adjacent the first mesa and second mesa.
2. The LED device of claim 1 , wherein the first anode region comprises a material selected from one or more of silver (Ag), indium tin oxide (ITO), nickel (Ni), palladium (Pd), platinum (Pt), and zinc oxide (ZnO).
3. The LED device of claim 1 , wherein the second anode region comprises a material selected from one or more of silver (Ag), indium tin oxide (ITO), nickel (Ni), palladium (Pd), platinum (Pt), and zinc oxide (ZnO).
4. The LED device of claim 1 , further comprising a first anode terminal on the first anode region.
5. The LED device of claim 1 , further comprises a second anode terminal on the second anode region.
6. The LED device of claim 1 , further comprising a cathode terminal on the cathode contact.
7. The LED device of claim 1 , further comprising a dielectric layer on the at least one sidewall of the trench.
8. The LED device of claim 7 , wherein the dielectric layer comprises one or more of silicon oxide (SiO 2 ), aluminum oxide (Al 2 O 3 ), silicon nitride (SiNx), titanium oxide (TiO 2 ), niobium oxide (Nb 2 O 5 ), zirconium oxide (ZrO 2 ), and hafnium oxide (HfO 2 ).
9. A method of operating the LED device of claim 1 , the method comprising:
flowing a current through the first anode region to emit light having a centroid wavelength less than 590 nm.
10. A method of operating the LED device of claim 1 , the method comprising:
flowing a current through the second anode region to emit light having a centroid wavelength greater than 610 nm.
11. A light emitting diode (LED) device comprising:
a first mesa array comprising a plurality of first mesas separated by a first trench, the first trench filled with a dielectric layer;
a second mesa array comprising a plurality of second mesas separated by a second trench, the second trench filled with the dielectric layer;
a first anode region on a top surface of the plurality of first mesas;
a second anode region on a top surface of the plurality of second mesas, the first anode region larger than the second anode region; and
a cathode contact adjacent to the first mesa array and the second mesa array,
the plurality of first mesas and the plurality of second mesas comprising semiconductor layers, the semiconductor layers including an n-type layer, an active layer, and a p-type layer, and the first trench and the second trench extending to the n-type layer.
12. The LED device of claim 11 , wherein the first anode region comprises a material selected from one or more of silver (Ag), indium tin oxide (ITO), nickel (Ni), palladium (Pd), platinum (Pt), and zinc oxide (ZnO).
13. The LED device of claim 11 , wherein the second anode region comprises a material selected from one or more of silver (Ag), indium tin oxide (ITO), nickel (Ni), palladium (Pd), platinum (Pt), and zinc oxide (ZnO).
14. The LED device of claim 11 , further comprising a first anode terminal on the first anode region.
15. The LED device of claim 11 , further comprising a second anode terminal on the second anode region.
16. The LED device of claim 11 , further comprising a cathode terminal on the cathode contact.
17. The LED device of claim 11 , wherein the dielectric layer comprises one or more of silicon oxide (SiO 2 ), aluminum oxide (Al 2 O 3 ), silicon nitride (SiNx), titanium oxide (TiO 2 ), niobium oxide (Nb 2 O 5 ), zirconium oxide (ZrO 2 ), and hafnium oxide (HfO 2 ).
18. A method of operating the LED device of claim 11 , the method comprising:
flowing a current through the first anode region to emit light having a centroid wavelength less than 590 nm.
19. A method of operating the LED device of claim 11 , the method comprising:
flowing a current through the second anode region to emit light having a centroid wavelength greater than 610 nm.