Abstract: Method of providing a substrate with a patterned metal layer disposed thereon, wherein a patterned metal mask is employed in conjunction with ion milling to form the pattern in the metal layer on the substrate. The metal mask as contemplated herein is made of a metallic masking mterial taken from the group consisting of vanadium, tantalum, titanium, and a titanium-tungsten alloy--vanadium being a preferred material because of its resistance to erosion or etching from ion milling coupled with its relatively fast etch rate in a plasma atmosphere. This method has particular application to magnetic bubble domain technology, wherein successive layers of a magnetically soft material, vanadium, and photoresist are deposited on a magnetic film capable of supporting magnetic bubble domain propagation. The layer of magnetically soft material is typically permalloy, and upon being patterned in a selected configuration, defines a bubble propagation path on the magnetic bubble-supporting film.

Abstract: Magnetic bubble domain generator and annihilator for use in a magnetic bubble domain memory device of the major-minor bubble propagation path type. The magnetic bubble domain generator and annihilator structure employs a thin metallic loop which is disposed adjacent to a bubble propagation path and is alternatively operable in both a bubble generation and bubble annihilation mode. A DC bias field is provided to the magnetic bubble domain memory circuit device and exists within the metallic loop of the bubble generator and annihilator structure. Upon applying a current pulse to the thin metallic loop from a pulse generator, the bubble generator and annihilator structure is caused to operate in one of the two possible modes. When the current pulse reduces the DC bias field below a predetermined value, the metallic loop operates as a generator to generate a magnetic bubble.

Abstract: Magnetic bubble domain replicator structure as employed in a magnetic bubble domain memory circuit device of the major-minor bubble propagation path type. The magnetic bubble domain replicate structure comprises a thin metallic conducting loop whose opposite sides are in contact with consecutive elements of magnetically soft material (e.g., permalloy) defining a propagation path aligned transversely with respect to a minor bubble propagation path employed for data storage. A DC bias field is provided for the magnetic bubble domain memory circuit and exists within the thin metallic loop of the replicate structure. The occurrence of a current pulse from a pulse generator directed to the thin metallic loop so as to reduce the DC bias field therein below a predetermined value at the same time that a magnetic bubble is within the metallic loop causes replication splitting the magnetic bubble into a pair of bubbles.

Abstract: Magnetic bubble domain memory circuit design in which magnetizable overlay patterns of magnetically soft material, e.g. permalloy, are provided on a magnetic bubble-supporting magnetic layer to define bubble propagation paths including transfer gate elements and combined replicate/transfer gate elements. The replicate/transfer gate elements are operable in two modes either combining the replicate and transfer bubble functions in a first mode or operable to effect a bubble transfer function in a second mode, wherein a magnetic bubble is transmitted from one section of a bubble circuit propagation path to another. Processing of data through the use of the magnetic bubble domains may occur in a first-in/first-out basis in one embodiment and on a last-in/last-out basis in another embodiment of the bubble memory. A pulse generator is associated with the transfer gate and the replicate/transfer gate structures.

Abstract: A magnetic bubble domain memory device employing a major row of contiguous regions for major loop bubble travel and a plurality of minor rows of contiguous regions for minor loop bubble travel, wherein the remainder of the magnetic domain-supporting layer in which the respective major and minor rows are provided includes ion-implanted regions. The edges of the ion-implanted regions adjacent the major and minor rows form rails to which magnetic bubble domains adhere and along which they may be propagated. The end region of each minor row is preferably positioned abreast a cusp between regions in the major row to effect zero degree phase transfer. Thin metallic loops are used for bubble generation and annihilation and, with respect to a Permalloy expansion detector, for replication. Metal masking improves the reliability of the boundaries between the non-implanted regions and the ion-implanted regions, especially with respect to the definition of the cusps between adjacent non-implanted regions in a row.

Abstract: A gapless propagation path structure for magnetic bubbles in a magnetic bubble domain memory system employing permalloy elements, wherein the drive field requirements for the in-plane rotating magnetic field may be reduced for high magnetization materials. An overlay pattern of magnetizable material, e.g. permalloy, is provided on a layer of magnetic material of a type suitable for the propagation of magnetic bubble domains therein. The magnetizable overlay pattern includes respective magnetizable elements forming the propagation paths for the magnetic bubble domains, the elements being so arranged as to provide a continuous track of magnetizable material included in the magnetizable overlay pattern, thereby defining a gapless propagation path for the magnetic bubble domains.

Abstract: A magnetic bubble detector utilizing a thin film optical waveguide. Light is optically coupled into the guide for propagation of linearly polarized light along a first axis thereof. Magnetic bubbles from a memory storage location are moved past the sensor on a second axis transverse the first. A sensor is provided for sensing changes in the polarization mode of the light propagating along the axis of the waveguide. The sensor includes an optical device for coupling light out of the waveguide. The passage of a magnetic bubble along the second axis past the waveguide will modulate the polarized light by the fringing field of the bubble and provide a light output signal from the sensor indicating the passage of each bubble.