Buried heterostructure lasers using mocvd growth over patterned substrates
CA 2084820 C · Owner: Berger, Paul Raymond · Inventors: Berger, Paul Raymond; Lopata, John; Dutta, Niloy Kumar
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention pertains to buried heterostructure lasers which have been fabricated using a single step MOCVD growth of an MQW laser structure over a pattern etched GaAs substrate. The wet chemical etching of grooves having a dovetailed cross-section and being parallel to the 011 direction in GaAs substrates produced reentrant mesas which resulted in isolated laser active regions buried by the AlGaAs cladding layer. The 250 µm long uncoated lasers emit at about 1 µm. Lasers with coated facets have threshold currents of 20 mA and emit >100 mW per facet under room temperature operation. The external differential quantum efficiency for currents of from 30 mA to about 50 mA is found to be …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed December 8, 1992 and granted December 9, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 8, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 8, 2014.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.