Patent ID: 7598527

Claim:
A photonic device comprising: a substrate; at least first and second epitaxial structures, said first epitaxial structure being a semiconductor laser structure and superimposed on a first portion of said second epitaxial structure and said second epitaxial structure being a semiconductor p-i-n photodetector structure and superimposed on said substrate; a trench passing through said second epitaxial structure and separating said second epitaxial structure into said first portion and at least a second portion; at least a first etched-facet laser fabricated in said first epitaxial structure, said first etched-facet laser having an etched reflective end facet passing downwardly into said first epitaxial structure but not completely through said substrate, an etched emitter end facet passing downwardly into said first epitaxial structure but not completely through said substrate, and an optical axis extending between said reflective end and said emitter end; and at least a monitoring photodetector fabricated in said second portion of said second epitaxial structure to monitor operation of said laser, said monitoring photodetector being positioned adjacent said reflective end facet of said laser and having a horizontal detector surface positioned to detect at least a portion of light being emitted from said reflective end facet of said laser; whereby said laser and said monitoring photodetector are monolithically integrated on said substrate.