Substrate independent distributed bragg reflector and formation method
AssigneeThe Board of Trustees of the University of Illinois
InventorsKuang-Chien Hsieh, Keh-Yung Cheng
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Abstract
Distributed Bragg reflectors may be formed in fewer layers by the method, which is capable of producing greater differences in indexes of refraction. Group III-V alternating layers are deposited. The microstructure of alternating layers is controlled to be different. A combination of alternating polycrystalline layers or amorphous and polycrystalline layers results. Alternate ones of the layers oxidize more quickly than the others. A lateral wet oxidation of the alternate ones of the layers produces a structure with large differences in indexes of refraction between adjacent layers. The microstructure between alternating layers may be controlled by controlling Group V overpressure alone or in combination with growth temperature.
Claims13
A method for forming a distributed Bragg reflector upon a device structure or a substrate, the method comprising steps of:
- forming a first Group III-V layer, the first layer being one of an Aluminum bearing material and a non Al bearing polycrystalline material;
- forming a second Group III-V layer upon the first layer, the second layer being the other of said Aluminum bearing material and said non Al bearing polycrystalline material;
- and
- laterally wet oxidizing Al bearing material layers formed in said step of forming.
A method for forming a distributed Bragg reflector upon a device structure or a substrate, the method comprising steps of:
- forming multiple material layers of Group III-V materials;
- altering at least one of a growth temperature, growth rate and a Group V overpressure while conducting said forming alternate microstructure of said multiple material layers from layer to layer;
- and
- laterally wet oxidizing a group of layers formed in said step of forming.
Dependencies are inferred from the claim text.