Abstract: The present invention concerns an anti-reflection coating for semiconductor lasers, in particular a coating on the laser facet with advantageous properties resulting in improved reliability and reduced probability of specific breakdowns, especially so-called catastrophic optical damages (CODs). It is a quarter-wave coating with a predetermined reflectivity, preferably between 0 and 10% and consists of or comprises SiNx:H. It is preferably applied by a Plasma-Enhanced Chemical Vapor Deposition (PE-CVD) process whose process parameters are controlled such that a desired optical thickness and refractive index of the coating are achieved. The PE-CVD process may be controlled to result in an Si/N ratio between about 0.5 and 1.5 and/or to produce a coating of essentially amorphous SiNx:H whose density approaches the density of crystalline Si3N4.

Abstract: The present invention concerns an anti-reflection coating for semiconductor lasers, in particular a coating on the laser facet with advantageous properties resulting in improved reliability and reduced probability of specific breakdowns, especially so-called catastrophic optical damages (CODs). It is a quarter-wave coating with a predetermined reflectivity, preferably between 0 and 10% and consists of or comprises SiNx:H. It is preferably applied by a Plasma-Enhanced Chemical Vapor Deposition (PE-CVD) process whose process parameters are controlled such that a desired optical thickness and refractive index of the coating are achieved. The PE-CVD process may be controlled to result in an Si/N ratio between about 0.5 and 1.5 and/or to produce a coating of essentially amorphous SiNx:H whose density approaches the density of crystalline Si3N4.

Abstract: A semiconductor laser arranged to emit at a given wavelength has a light emitting facet carrying a phase-shifting anti-reflection coating, whose thickness is one quarter that of the given wavelength. Coupling at the light emitting facet is arranged to take place at the minimum of the standing wave.

Abstract: A semiconductor laser diode, and a method for producing the semiconductor laser diode, includes a waveguide being terminated by a back facet and a front facet and a front facet coating and a back facet coating having a reflectivity providing for controlled decoupling of light at the front facet from the standing lightwave in the waveguide. The front facet coating includes a stack of layers providing for a phase shift of the standing lightwave within the waveguide such that the intensity of the lightwave at the front facet, where the light is decoupled from the standing lightwave, has a relative minimum.

Abstract: One or more monolayers of cerium arrayed on the surface of a niobium metal acts as a catalyst to oxidation of the niobium at ambient temperature and results in a very thin, very high quality insulating layer which may be configured by patterning of the catalyst. Significant amounts of Nb.sub.2 O.sub.5 are formed at pressures as low as 6.6.times.10.sup.-6 Pa, promoted by the presence of the cerium. This catalytic activity is related to the trivalent to tetravalent valence change of the cerium during oxidation. The kinetics of Nb.sub.2 O.sub.5 formation beneath the oxidized cerium shows two stages:the first stage is fast growth limited by ion diffusion;the second stage is slow growth limited by electron tunneling.Other catalytic rare earths usable instead of cerium are terbium and praseodymium; other substrate materials usable instead of niobium are aluminum, hafnium, silicon and tantalum, or oxidizable alloys thereof.