HIGH-EFFICIENCY LIGHT EMITTING DIODE
A light emitting diode (LED) includes a semiconductor material with an active region. The active region is disposed in the semiconductor material to produce light in response to a voltage applied across the semiconductor material. The active region includes a wide bandgap region disposed to inhibit charge transfer from a central region of the LED to the lateral edges of the LED. The active region also includes a narrow bandgap region disposed in the central region with the wide bandgap region disposed about the narrow bandgap region, and the narrow bandgap region has a narrower bandgap than the wide bandgap region.
1 . A light emitting diode (LED), comprising:
a semiconductor material including an active region, wherein the active region is disposed in the semiconductor material to produce light in response to a voltage applied across the semiconductor material, and wherein the active region includes:
a wide bandgap region disposed adjacent to lateral edges of the LED, wherein the wide bandgap region is disposed to inhibit charge transfer from a central region of the LED to the lateral edges of the LED; and
a narrow bandgap region disposed in the central region with the wide bandgap region disposed about the narrow bandgap region, wherein the narrow bandgap region produces the light, and wherein the narrow bandgap region has a narrower bandgap than the wide bandgap region.
2 . The LED of claim 1 , wherein the wide bandgap region and the narrow bandgap region have different elemental compositions.
3 . The LED of claim 2 , wherein the wide bandgap region includes Al(GaIn)AsP or AlAs.
4 . The LED of claim 1 , wherein at least part of the wide bandgap region is oxidized.
5 . The LED of claim 1 , wherein the wide bandgap region and the narrow bandgap region have the same elemental composition, and wherein the narrow bandgap region has a higher density of states than the wide bandgap region.
6 . The LED of claim 1 , further comprising trenches disposed in the semiconductor material, wherein the trenches extend from a surface of the semiconductor material through the narrow bandgap region, and wherein the wide bandgap region is disposed in the trenches to surround the narrow bandgap region.
7 . The LED of claim 1 , further comprising a substrate including a trench disposed in the substrate, wherein the wide bandgap region is conformally disposed on walls of the trench, and wherein the semiconductor material is disposed in the trench.
8 . The LED of claim 1 , further comprising a first electrode and a second electrode, wherein the semiconductor material is disposed between the first electrode and the second electrode.
9 . The LED of claim 8 , wherein the first electrode is transparent.
10 . The LED of claim 1 , further comprising a plurality of LEDs including the LED, wherein the plurality of LEDs is arranged into an array including rows and columns.
11 . The LED of claim 10 , further comprising control logic coupled to the plurality of LEDs, wherein the control logic controls operation of the plurality of LEDs.
12 .- 23 . (canceled)