Large intermixing in the InGaP/InAlGaP laser structure using stress engineering at elevated temperature

Abstract

In this paper, a thermally induced dielectric strain on quantum well intermixing (QWI) technique is employed on tensilestrained InGaP/InAlGaP laser structure, to promote inter-diffusion, in conjunction with cycle annealing at elevated temperature. A bandgap blueshift as large as large as ~250meV was observed for samples capped with a single and bilayer of the dielectric film (1μm-SiO2 and 0.1μm-Si3N4) and annealed at a high temperature (700-1000oC) for cycles of annealing steps. Samples subjected to this novel QWI technique for short duration and multiple cycle annealing steps shown a high degree of intermixing while maintaining strong photoluminescence (PL) intensity, narrow full wave at half maximum (FWHM) and good surface morphology. Laser devices fabricated using this technique, lased at a wavelength of 608nm with two facet power of ~46mW, indicating the high quality of the material. Our results show that thermal stress can be controlled by the engineering dielectric strain opening new perspectives for QWI of photonics devices.