Deposition and Measurements of Electron-Beam-Evaporated SiO sub x Anti-Reflection Coatings on InGaAsP Injection Laser Facets.

We describe in-situ monitored, electron-beam evaporated, non- stoichiometric silicon monoxide (SiO sub x) anti-reflection coatings on 1.5micron laser facets. We demonstrate reflectivities of 0.05% on devices with one facet coated and mean reflectivities of 0.07% for traveling-wave amplifiers with both facets coated. The polarization dependent reflectivities were measured at several wavelengths for both device types and were found to be broad-band (R 0.1% over an approximate wavelength range of 400angstroms). The reflectivities obtained using measurements of the noise and gain spectra were compared. We conclude that measurements using the noise spectrum tend to under-estimate the reflectivities.