U.S. Philips Corporation

North American Philips Corporation

Jens-Peter Krumme

Volker Doormann

Klaus Witter

Heinrich Heitmann

Christoph Schmelzer

Reimar Spohr

Hans O Dammann

Bernhard Hill

Hans-Jurgen Schmitt

Klaus Drews

Jurgen Seidenberg

Wolfgang Radtke

John Petruzello

Wolfgang J Radtke

Norbert Thorweihe

Volker Doorman

A method of manufacturing ion garnet layers having refractive indices n adjusted in a defined manner and lattice constants a.sub.o adjusted in a defined manner, in which the layers are deposited on a substrate by means of rf cathode sputtering using a target comprising substantially a garnet phase besides residual phases of substantially the same sputtering rates in a noble gas plasma of an ion energy of the ions bombarding the growing layer of smaller than 10.sup.2 eV and at a pressure in the range from 0.1 to 2.0 Pa, the noble gas being doped with up to 5% by volume of at least one reactive gas.

Method of manufacturing iron garnet layers

The invention relates to a planar optical isolator having a magneto optical gyrotropic layer and an anisotropic birefringent layer which are proportioned so that the non-reciprocal rotation of polarisation of the light (Faraday rotation) resulting from the action of a magnetic field in the forward direction of the isolator is at least substantially negatively equal to the reciprocal rotation of polarisation as a result of the birefringence, so that a TE-mode in the forward direction is guided with low damping, measures being taken for the intensive attenuation of at least one TM-mode. An isolator having a high isolating effect in which magneto optical gyrotropic layers and anisotropic birefringent layers can be connected epitaxially is obtained in that the waveguiding core layer comprises two rare earth-iron garnet (YIG) layers which are differently doped to obtain different specific birefringence.

Planar optical isolator

A method of manufacturing iron garnet layers on a substrate, in a layer sequence of different order by means of RF-cathode sputtering in an inert gas plasma, using a target comprising predominantly an iron garnet phase in addition to residual phases having a substantially equal sputtering rate, the ions of said inert gas plasma bombarding the growing layer having an ion energy of less than 10.sup.2 eV and a pressure in the range from 0.1 to 2.0 Pa, in which method RF-power is fed into the target electrode (cathode) at a RF-voltage of approximately 200 V.sub.rms, thereby first depositing an amorphous to X-ray amorphous iron garnet layer as an intermediate layer at a substrate temperature below 460.degree. C. and, subsequently, a polycrystalline iron garnet layer at a substrate temperature exceeding 520.degree. C., while simultaneously applying a RF-voltage of approximately 50 V.sub.rms to the substrate electrode, which voltage is linearly reduced during the deposition of the first 5-10 nm of the layer to a floating potential relative to earth.

A method is disclosed of manufacturing an optical stripline waveguide for use in non-reciprocal optical components, in which a monocrystalline waveguide strip having a refractive index n.sub.2, which is surrounded by material with a lower refractive index n.sub.1, is provided on a monocrystalline substrate, the waveguide strip and the material surrounding it being deposited on a substrate by means of RF cathode sputtering (sputter epitaxy) in an inert gas plasma, making use of a target which contains mainly iron garnet phase, together with other phases with an almost equal sputtering rate, the crystal lattice of said substrate being locally disturbed in the surface regions where no waveguide strip is to be grown, thereby forming a lattice disorder.

Method of manufacturing an optical stripline waveguide for

A method of manufacturing structured epitaxial layers is discribed having monocrystalline layer regions adjacent to layer regions of a different order situated on a monocrystalline substrate whose crystal lattice is disturbed in locally bounded surface regions. A lattice disorder is formed with, the layers being manufactured by means of RF cathode sputtering (sputter epitaxy) in an inert gas plasma, and making use of a target containing the elements which contribute in the form of phases with an almost identical sputtering rate to the formation of the layer.

Method of manufacturing structured epitaxial layers on a substrate

A magnetic layer for storing information in the form of a fixed, two-dimensional array of magnetic domains. The magnetic layer can be magnetized in either of two opposite directions normal to the plane of the layer. The walls of the domains are fixed by local gradients in the value and direction of the magnetic anistropy and in the value and direction of the magnetic exchange energy of the magnetic layer. The local gradients may be caused by a relatively high defect density at the domain wall locations, by implanting ions into the magnetic layer at the locations of the domain walls thereby causing a local expansion of the crystal lattice of the layer, and/or by etching a multiplicity of nonconnected tapering channels in and substantially perpendicular to the plane of the magnetic layer at these locations. Where tapering channels are used, the magnetic layer is provided on a substrate such that the crystal lattice constant of the magnetic layer is different from the crystal lattice constant of the substrate. In another embodiment, the local gradients can be the result of the epitaxial growth of a magnetic layer on a substrate which has a plurality of nonconnected etched channels at the domain wall locations.

Method of making a magnetic memory layer

A magnetic layer for storing information in the form of a fixed, two-dimensional array of magnetic domains. The magnetic layer can be magnetized in either of two opposite directions normal to the plane of the layer. The walls of the domains are fixed by local gradients in the value and direction of the magnetic anisotropy and in the value and direction of the magnetic exchange energy of the magnetic layer. The local gradients may be caused by a relatively high defect density at the domain wall locations, by implanting ions into the magnetic layer at the locations of the domain walls thereby causing a local expansion of the crystal lattice of the layer, and/or by etching a multiplicity of non-connected tapering channels in and substantially perpendicular to the plane of the magnetic layer at these locations. Where tapering channels are used, the magnetic layer is provided on a substrate such that the crystal lattice constant of the magnetic layer is different from the crystal lattice constant of the substrate. In another embodiment, the local gradients can be the result of the epitaxial growth of a magnetic layer on a substrate which has a plurality of non-connected etched channels at the domain wall locations.

Magnetic memory layer

Substrate holder for etching thin films by means of an ion beam in which a driving device moves the surface of a substrate placed on a turntable with respect to the ion beam, which holder includes a friction disk which rotates in rolling contact with a surface of a driving disk carrying the turntable and is spaced from the axis of the driving disk by a distance equal to that at which the point of impact of the ion beam on the substrate is located.

Substrate holder for etching thin films

The invention relates to a device for magneto-optic memories controlled by light and/or heat in an external magnetic field, in which the magneto-optic material of the memory has a photoconductive layer which can be activated by the control beam and which can be controlled by means of electrodes provided thereon via a current or voltage source.

Growing community of inventors

Hamburg, Germany

Jens-Peter Krumme