Oxidation smoothing of sidewall roughness in AlGaAs heterostructure waveguides

A 10-100 fold reduction in sidewall roughness of etched AlGaAs ridge structures is demonstrated using a wet thermal oxidation process modified through addition of <1% O/sub 2/ to the N/sub 2/ carrier gas, potentially enabling high index contrast waveguides with ultra-low scattering loss for ring resonator and other photonics device applications.