Multiple cavity etched-facet DFB lasers
AssigneeBinOptics Corporation
InventorsAlex Behfar, Malcolm Green, Norman Kwong, Cristian Stagaresen
Life of this patent
Estimating the term…
Abstract
A semiconductor chip has at least two DFB etched facet laser cavities with one set of facets with AR coatings and a second set of etched facets with HR coatings that have a different relative position with respect to the gratings. This creates a difference in the phase between each of the etched facets and the gratings which changes the operational characteristics of the two laser cavities such that at least one of the lasers provides acceptable performance. As a result, the two cavity arrangement greatly improves the yield of the fabricated chips.
Claims21
A semiconductor chip, comprising:
- a substrate;
- an epitaxial laser structure on said substrate, said epitaxial laser structure including a grating layer;
- a periodic grating formed in said grating layer;
- at least first and second independent distributed feedback laser cavities formed in said epitaxial structure, said first and second laser cavities being spaced apart from one another in said epitaxial structure;
- said first distributed feedback laser cavity having a first etched facet defining a first end of said first distributed feedback laser cavity and forming a first phase with said grating;
- and
- said second distributed feedback laser cavity having a first etched facet defining a first end of said second distributed feedback laser cavity and forming a second phase with said grating, said second phase being different than the first phase,
- whereby the likelihood of at least one of said first and second laser cavities being operational is increased.
A semiconductor chip, comprising:
- a substrate;
- an epitaxial laser structure on said substrate;
- said epitaxial laser structure having a grating layer with a periodic grating of pitch Λ formed therein;
- at least first and second independent distributed feedback laser cavities formed in said epitaxial structure, said first and second laser cavities spaced apart from one another in said epitaxial structure;
- said first distributed feedback laser cavity having a first length and a first etched facet defining a first end of said first distributed feedback laser cavity that forms a first phase with said grating;
- and
- said second distributed feedback laser cavity having a second length and a first etched facet defining a first end of said first distributed feedback laser cavity that forms a second phase with said grating;
- wherein said first and second lengths are different from one another and said first and second phases are different from one another.
Dependencies are inferred from the claim text.