Monolithic optoelectronic twe-component structure for high frequencies and low optical insertion loss
AssigneesCogo Optronics, Inc., Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
InventorsKelvin Prosyk, Ronald Kaiser, Karl-Otto Velthaus
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Abstract
A monolithic optoelectronic device has a spot-size converter optically connected to a waveguide. The overclad extending over the core of the waveguide is thinner and more highly doped that the overclad of the spot-size converter. This structure can be made by applying a process of selective etching and enhanced regrowth to create selective regions of the overclad of different thickness or doping.
Claims14
A monolithic optoelectronic device comprising;
- a waveguide containing a core, an overclad adjacent to the core, and at least one electrode connected to at least a portion of the waveguide;
- and
- a spot-size converter optically connected to the waveguide, said spot-size converter containing a core and an overclad adjacent to the core;
- wherein the overclad of the waveguide is more highly doped than the overclad of the spot-size converter.
A monolithic optoelectronic device comprising:
- a waveguide containing a core, an overclad adjacent to the core, and at least one electrode connected to at least a portion of the waveguide;
- and
- a spot-size converter optically connected to the waveguide, said spot-size converter containing a core and an overclad adjacent to the core;
- wherein the overclad of the waveguide is thinner than the overclad of the spot-size converter.
A method for fabricating a monolithic optoelectronic device having a waveguide containing a core, an overclad adjacent to the core, and at least one electrode connected to at least a portion of the waveguide;
- and a spot-size converter optically connected to the waveguide containing a core and an overclad adjacent to the core;
- said method comprising:
- providing a wafer having a core and a overclad adjacent to the core made of a highly-doped semiconductor material;
- placing a mask on the wafer covering those areas of the overclad on which electrodes of the waveguide are to be formed;
- etching away at least a portion of areas of the overclad that are not covered by the mask;
- replacing the etched areas of the overclad with semiconductor material that is less highly doped and having areas if different thickness, so that the overclad of the waveguide is thinner than the overclad of the spot-size converter;
- and
- forming electrodes of the waveguide on selected unetched areas of the overclad.
Dependencies are inferred from the claim text.