Facet protection of (AlGa)As lasers using SiO2 sputter deposition

Abstract
Sputter‐deposited SiO2 films on (AlGa)As DH laser facets were found by chemical erosion tests and Auger spectroscopy to have strong adhesion and an abrupt film‐facet interface profile. Half‐wave coatings by sputtering allowed stable long‐term operation of lasers over several thousand hours at 10–20‐mW (0.7–1.2 mW/μm) power levels at room temperature, almost without change from the initial value of threshold current and optical power.