Fabrication of low-threshold InGaAs/GaAs ridge waveguide lasers by using in situ monitored reactive ion etching

In situ laser-monitored reactive ion etching is used to control ridge formation with 150-AA accuracy in fabricating double heterostructure InGaAs-GaAs strained layer single-quantum-well ridge waveguide lasers grown by molecular-beam epitaxy. Continuous-wave threshold current as low as 3.6 mA was obtained on devices with cleaved mirrors. High-reflectivity (96-70%) coated devices have the lowest threshold current at 2.1 mA.>