Weakly index guided buried-stripe type 980 nm laser diodes grown by a combination of gas source molecular beam epitaxy and metalorganic vapor phase epitaxy with an AlGaAs/InGaP/GaAs double etch stop structure

In order to fabricate weakly index guided buried-stripe type 980 nm laser d iodes (LDs) precisely and reproducibly; we have developed a novel double et ch stop (DES) structure which consists of AlGaAs/ZnGaP/GaAs layers. By empl oying the DES structure, an effective refractive index step (Delta n(eff)) of 3.6 x 10(-3) and a waveguide bottom width (W-b) of 2.2 mu m were realize d to maintain a stable transverse mode. The LDs were fabricated by a combin ation of gas-source molecular beam epitaxy (GS-MBE) and metalorganic vapor phase epitaxy (MOVPE) on a 2-inch wafer and showed uniformly high performan ce, especially in the region within a 15.5 mm radius from the center. A hig h kink level of 315 +/- 15 mW was achieved. Considering wafer uniformity, w e estimated that Delta n(eff) and W-b should be controlled to about 3.6 x 1 0(-3) +/- 3.5 x 10(-4) and 2.22 +/- 0.06 mu m, respectively, under the cond ition of a vertical optical confinement factor Gamma is approximately equal to 1.16%/well. We have also confirmed the high quality of the Entire proce ss, including the DES method, by employing a reliability test at 200 mW lig ht output power up to 2500 h.