Reactive ion etching of InAlAs with Ar/Cl₂ mixtures for ridge waveguide lasers

We have investigated the etching characteristics of InAlAs for reactive ion etching (RIE) with mixtures of argon (Ar) and chlorine (Cl2). Nearly vertical walls and a smooth surface morphology can be achieved for etch rates of up to 200 nm/min. For an application we have produced dry-etched ridge waveguide lasers in the In(Ga)AlAs/InGaAs material system with threshold currents as low as 12 mA. © 1993.