Abstract: Our wafer scale processing techniques produce chip-laser-diodes with a diffraction grating that redirects output light out the top and/or bottom surfaces. Noise reflections are carefully controlled, allowing significant reduction of the signal fed to the active region. In GaAs substrate embodiments, prior art gratings have generally been in AlGaAs. By using a InGaP layer epitaxially grown over (preferably directly on the top of) the core, our lasers can have an etch-stop-layer for accurate vertical location of the grating, and provides an aluminum-free grating (avoiding problems of aluminum oxidation), and also enables fabrication of saw-tooth gratings using anisotropic etching of InGaP.

Abstract: This narrow-band coherent light, (light that is virtually all in-phase and at, or essentially at, the same wavelength) grating-coupled, diode-chip-laser improvement enables, for the first time, combining the functional advantages of non-semiconductor-chip (e.g., fluid) lasers with the efficiency, economy, and convenience of semiconductor-chip-manufacturing (wafer processing), while providing significantly higher power than prior art semiconductor-chip diodes. It utilizes a manufacturable grating that couples output light “vertically” out of a horizontal, active-region-containing core, and generally minimizes reflections that would cause loss and noise. All reflections from the grating back into the active region are essentially eliminated (to less than 0.1% and preferably less than 0.01% of the light diffracted out of said structure).