International Business Machines Corporation

Marcel Gasser

Ernst E Latta

Peter Vettiger

Peter Roentgen

Christoph S Harder

Abram Jakubowicz

Ronald F Broom

Albertus Oosenbrug

Ernst-Eberhard Latta

Heinz Richard

Hans Peter Dietrich

Eberhard Latta

Ernst Eberhard Latta

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.

Semiconductor lasers and method for making the same

A method for cleaving semiconductor wafers, or segments thereof, which comprises placing the wafer, provided with scribe lines defining the planes where cleaving is to take place, inbetween a pair of flexible transport bands and guiding it around a curved, large radius surface thereby applying a bending moment. With a moment of sufficient magnitude, individual bars are broken off the wafer as this is advanced, the bars having front-and rear-end facets. On cleaving, each bar, while still pressed against the curved surface, is automatically separated whereby mutual damage of the facets of neighboring bars is prevented. For further handling, e.g. for the transport of the bars to an evaporation station for passivation layer deposition, provisions are made to keep the bars separated. Cleaving and the subsequent passivation coating can be carried out in-situ in a vacuum system to prevent facet contamination prior to applying the passivation.

Method for batch cleaving semiconductor wafers and coating cleaved facets

A method for passivating mirrors in the process of fabricating semiconductor laser diodes is disclosed. Key steps of the method are: (1) providing a contamination-free mirror facet, followed by (2) an in-situ application of a continuous, insulating (or low conductive) passivation layer. This layer is formed with material that acts as a diffusion barrier for impurities capable of reacting with the semiconductor but which does not itself react with the mirror surface. The contamination-free mirror surface is obtained by cleaving in a contamination-free environment, or by cleaving in air, followed by mirror etching, and subsequent mirror surface cleaning. The passivation layer consists of Si, Ge or Sb.

Method for mirror passivation of semiconductor laser diodes

A process for reducing the particle current in the sub-gap range of all-Nb Josephson junctions. The process results in junctions having substantially increased values of V.sub.m. In order to reduce the single particle current, the reaction between the barrier layer oxide and the counter electrode is prevented by additional process steps. After forming the tunnel barrier (4) and before depositing the counter electrode (9), the tunnel barrier surface is covered with a thin, non-continuous layer (5) of a material such as gold which is not reacting with oxygen at process conditions. Subsequently, the non-covered barrier layer surface regions (7) are strongly oxidized thereby forming an oxide layer (8) of sufficient thickness to prevent electron tunneling in these regions.

Process for producing niobium Josephson junctions

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Zurich, Switzerland

Marcel Gasser