Northrop Grumman Systems Corporation

Wisconsin Alumni Research Foundation

University of Illinois

Michael P Nesnidal

David V Forbes

Luke J Mawst

Nelson Tansu

Eric Warren Stiers

Steven Meassick

Darren M Hansen

Troy J Goodnough

An optical device () including a first semiconductor layer () on which is deposited a dielectric layer that is patterned and etched to form dielectric strips () as part of a diffraction grating layer. Another semiconductor layer () is grown on the first semiconductor layer () between the dielectric strips (), resulting in alternating dielectric sections () and semiconductor sections. In an alternate embodiment, a dielectric layer is deposited on a first semiconductor layer (), and is patterned and etched to define dielectric strips (). The semiconductor layer () is etched to form openings () between the dielectric strips (). Another semiconductor material () is grown within the openings () and then another semiconductor layer () is grown over the entire surface after removing the dielectric strips (). Either embodiment may be modified to provide diffraction grating with air channels ().

High index-step grating fabrication using a regrowth-over-dielectric process

An optical device including a first semiconductor layer on which is deposited a dielectric layer that is patterned and etched to form dielectric strips that are part of a diffraction grating layer. A second semiconductor layer is grown on the first semiconductor layer between the dielectric strips to provide alternating dielectric sections and semiconductor sections. Via channels can be patterned and etched through the second semiconductor layer so that dielectric strips can be removed to form dielectric air channels.

Process for fabricating a semiconductor diffraction grating using a sacrificial layer

As edge-emitting semiconductor laser incorporating a narrow waveguide design is disclosed. The narrow waveguide expands the lateral mode size, creates a large modal spot size, and insures higher-order modes are beyond cutoff. Separate current confinement allows the current injection region to match the mode size. The resulting device exhibits single-mode operation with a large spot-size to high output powers.

Narrow lateral waveguide laser

An optical device ( ) including a first semiconductor layer ( ) on which is deposited a dielectric layer that is patterned and etched to form dielectric strips ( ) as part of a diffraction grating layer. Another semiconductor layer ( ) is grown on the first semiconductor layer ( ) between the dielectric strips ( ) to provide alternating dielectric sections ( ) and semiconductor sections. In an alternate embodiment, a dielectric layer is deposited on a first semiconductor layer ( ), and is patterned and etched to define dielectric strips ( ). The semiconductor layer ( ) etched to form openings ( ) between the dielectric strips ( ). A semiconductor material ( ) is grown within the openings ( ) and then another semiconductor layer ( ) is grown over the entire surface after removing the dielectric strips. Either embodiment may be modified to provide a diffraction grating with air channels ( ).

Growing community of inventors

Oregon, WI, United States of America

Michael P Nesnidal