Strain balanced direct bandgap aluminum indium phosphide quantum wells for light emitting diodes
Described herein are optoelectronic devices and methods incorporating strain balanced direct bandgap Al x In 1-x P multiple quantum wells. The described devices are strain balanced in that the net strain between the ordered quantum wells and barriers is low, or in some cases zero. Advantageously, the described devices may be specifically designed for higher efficiency than existing Al x In 1-x P and may be grown on commercially available GaAs substrates.
1 . An optoelectronic device comprising:
a well layer of ordered Al x In 1-x P quantum wells;
a barrier layer of ordered Al x In 1-x P quantum barriers in electronic communication with said well layer;
wherein said well layer and said barrier layer are strain balanced;
wherein said well layers have an Al fraction less than the Al fraction of said barrier layers.
2 . The device of claim 1 , wherein the well layer comprises CuPt atomically ordered Al x In 1-x P quantum wells.
3 . The device of claim 1 , wherein the well layer, the barrier layer or both are zero order.
4 . The device of claim 1 comprising a plurality of well layers and a plurality of barrier layers.
5 . The device of claim 4 , wherein said well layers and said barrier layers are in an alternating configuration.
6 . The device of claim 1 further comprising one or more Al x In 1-x P clad layers.
7 . The device of claim 1 further comprising a disordered Al x In 1-x P n-type clad layer and a disordered Al x In 1-x P p-type clad layer.
8 . The device of claim 1 , wherein strain balanced refers to a net strain between said well layers and said barrier layers is substantially zero.
9 . The device of claim 8 , wherein said well layers have a non-zero compressive strain and said barrier layers have a non-zero tensile strain.
10 . The device of claim 1 , wherein said well layers, said barrier layers or both are capable of being grown on a GaAs substrate.
11 . The device of claim 10 , wherein said well layers, said barrier layers or both are grown on a GaAs substrate using an intermediate metamorphic buffer.
12 . The device of claim 1 , wherein said well layers, said barrier layers or both further comprise Ga and have the formula (Al 1-y Ga y ) x In 1-x P.
13 . The device of claim 12 , wherein said Ga has a fraction less than or equal to 0.1.
14 . The device of claim 6 , wherein said Al x In 1-x P clad layers further comprises Ga and has the formula (Al 1-y Ga y ) x In 1-x P.
15 . The device of claim 14 , wherein said Ga has a fraction less than or equal to 0.1.
16 . The device of claim 1 , wherein the device is capable of selectively emitting light at a wavelength selected from the range of 560 nm to 650 nm.
17 . The device of claim 1 , wherein the device is a light emitting diode.