Method of fabricating waveguide using sacrificial spacer layer
AssigneeThe United States of America as represented by the Director, National Security Agency
InventorsJohn L. Fitz, Daniel S. Hinkel, Scott C. Horst
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Abstract
The present invention is a method of fabricating a waveguide using a sacrificial spacer layer. The first step in this process is to fabricate the underlying optical semiconductor structure. A trench is then etched in this structure and a sacrificial spacer layer is deposited in the trench. The waveguide is then created in the trench on the sacrificial spacer layer. User-defined portions of the sacrificial spacer layer are subsequently removed to create air gaps between the waveguide and the sidewalls of the trench in the optical semiconductor.
Claims17
A method for creating an optical semiconductor device comprising the steps of:
- a) selecting a base structure;
- b) depositing a first cladding layer on the base structure;
- c) depositing a core layer on the first cladding layer;
- d) depositing a second cladding layer on the core layer;
- e) depositing a cap layer on the second cladding layer;
- f) depositing an upper contact on the cap layer;
- g) forming a trench in through a user-definable portion of the upper contact, cap layer, second cladding layer, the core layer, the first cladding layer, to at least a user-definable depth in the first cladding layer, wherein the trench is of a user-definable width, and where the trench has two walls and a floor;
- h) depositing a sacrificial spacer layer on the two walls and floor of the trench;
- i) fabricating a waveguide on the sacrificial spacer layer;
- and
- j) removing a user-definable portion of the sacrificial spacer layer, where a user-definable portion of the sacrificial spacer layer remains on the floor of the trench to anchor the waveguide.
Dependencies are inferred from the claim text.