Buried-heterostructure lasers fabricated by in situ processing techniques

We describe, for the first time, the preparation of InGaAs/InP homojunction confined buried-heterostructure lasers by high vacuum processing techniques. Lithography and waveguide mesa etching were carried out using ultrathin native oxide masking, focused Ga ion beam writing, and free Cl2 etching. Base laser structures and overgrowth were carried out by atmospheric pressure metalorganic vapor phase epitaxy. The resulting lasers have low-threshold currents of ∼62 mA.