Abstract: A voltage equal to the threshold value of a TFT (106) is held in capacitor unit (109). When a video signal is inputted from a source signal line, the voltage held in the capacitor unit is added thereto and a resultant signal is applied to a gate electrode of the TFT (106). Even when a threshold value is varied for each pixel, each threshold value is held in the capacitor unit (109) for each pixel. Thus, the influence of a variation in threshold value can be eliminated. Further, holding of the threshold value is conducted by only the capacitor unit (109) and a charge does not move at writing of a video signal so that a voltage between both electrodes is not changed. Thus, it is not influenced by a variation in capacitance value.

Abstract: A voltage equal to the threshold value of a TFT (106) is held in capacitor unit (109). When a video signal is inputted from a source signal line, the voltage held in the capacitor unit is added thereto and a resultant signal is applied to a gate electrode of the TFT (106). Even when a threshold value is varied for each pixel, each threshold value is held in the capacitor unit (109) for each pixel. Thus, the influence of a variation in threshold value can be eliminated. Further, holding of the threshold value is conducted by only the capacitor unit (109) and a charge does not move at writing of a video signal so that a voltage between both electrodes is not changed. Thus, it is not influenced by a variation in capacitance value.

Abstract: An extensible three dimensional circuit having parallel array channels includes an access layer and crossbar array layers overlying the access layer and being electrically connected to the access layer. The crossbar array layers include parallel channels, the parallel channels being formed from two classes of vias, the first class being pillar vias connected to relatively short stub lines, and the second class being traveling-line vias connected to long lines that travel away from the via; pillar vias and traveling-line vias being configured to connect to crossing lines such that each crossing point between the lines is uniquely addressed by one pillar via and one traveling-line via. Programmable crosspoint devices are disposed between the crossing lines.

Abstract: Systems and methods are provided for digital transport of paramagnetic particles. The systems and methods may include providing a magnetic garnet film having a plurality of magnetic domain walls, disposing a liquid solution on a surface of the magnetic garnet film, wherein the liquid solution includes a plurality of paramagnetic particles, and applying an external field to transport at least a portion of the paramagnetic particles from a first magnetic domain wall to a second magnetic domain wall of the plurality of magnetic domain walls.

Abstract: A separation procedure for separating a selected desired or undesired population from a biological sample utilizing relatively heavy, dense particles and gravity sedimentation. The particles have one or more reactants bound thereto which are specific to and will bind with the selected population. The particles preferably are mixed with the sample by repeatedly causing the particles to settle through a substantial portion of the sample to bind to the selected population. The particles with the bound selected population then are allowed to preferentially settle in the sample and the supernatant including an enriched population is separated from the particles with the selected population bound thereto. The enriched populations in the biological sample supernatant can be further enriched by multiple removal steps.

Abstract: Disclosed is a flow through particle analyzing cell differentiating apparatus for optical and electronic measurements on a stream of particles in which a hydrodynamically focoussed stream is passed into and through a point focussed beam of radiated energy whereby the beam is scattered by the stream to impinge upon light responsive signal operating members disposed adjacent the cell at angular positions relative to the beam axis of from about 10.degree. to 70.degree..

Abstract: An improved magnetic bubble memory device includes a continuous propagator overlay on a sheet of magnetic material. The propagator overlay being adapted to reduce the statistical switching effects and overall coercivity of the propagator overlay. The propagator overlay consists of multiple layers of soft magnetic material being alternately arranged with non-magnetic material, in a geometric pattern specified so as to produce domain walls only internal to the pattern boundary, the soft magnetic material being chosen for its initial low coercivity characteristics and having characteristics approaching zero magneto-striction.

Abstract: A magnetic bubble memory device comprises a bubble propagation path defined by a wide-gap pattern. This bubble propagation pattern has a geometry which is favorable for gaining an increase in density and which can provide a high propagation characteristic.

Abstract: A magnetic-bubble memory device having a bubble propagation track, defined by patterns of magnetically soft material, along which magnetic bubbles propagate in response to an in-plane rotating magnetic drive field. The bubble propagation track has a first track and a second track interconnected by a turn and defined by known hook-shaped wide-gap patterns or by modified wide-gap patterns. The turn includes a crooked bar-shaped pattern. An end portion of the last pattern of the first track is positioned opposite the inner edge of the crooked bar-shaped pattern, and an end portion of the crooked bar-shaped pattern is positioned adjacent to the first pattern of the second track. Such a bubble propagation track makes it possible to realize a 4 .mu.m period, 4 Mb bubble memory.

Abstract: A highly density magnetic bubble memory device has bubble propagation paths having different pattern periods. The distance between a propagation path having shorter period and a magnetic film for holding magnetic bubbles is made smaller than that between propagation path having longer period and the magnetic film. An insulating layer formed between the propagation path and the magnetic film through another insulating layer has a declining slope having an angle of 60.degree. or less, thereby ensuring steady propagation of the magnetic bubbles along the propagation path.

Abstract: A magnetic bubble memory device is disclosed which is equipped with a minor loop of a magnetic bubble propagation track formed by ion implantation and a major loop or major line of a magnetic bubble propagation track consisting of a soft magnetic film and in which the thickness of an insulating film at at least the junction between the minor loop and the major loop or major line is less than the thickness of insulating film at the major line or major loop.

Abstract: A magnetic-bubble memory device comprising a bubble propagation path defined by patterns of magnetically soft material, along which magnetic bubbles propagate in response to an in-plane rotating magnetic drive field. The bubble propagation path has a first track and a second track and a connection for interconnecting the first track and the second track. The first track is defined by conventional propagation patterns, and the second track is defined by known hook-shaped wide-gap patterns or modified wide-gap patterns. The connection includes a connection pattern having one end portion arranged with respect to the terminal pattern of the first track in the same constructional relationship as that between the successive patterns of the first track and another end portion arranged with respect to the terminal pattern of the second track in the same constructional relationship as that between the successive patterns of the second track. Such a bubble propagation track makes it possible to realize a 4 .mu.

Abstract: A solid state device including glass containing SiO.sub.2, consisting essentially of the composition, in percent by weight, in the range of:______________________________________ SiO.sub.2 95-99.5 Al 0.5 to 5.0.

Abstract: A field-access bubble memory chip has a plurality of permalloy elements overlying an insulating layer. The permalloy elements are configured and positioned to define a plurality of paths for propagating magnetic bubbles under the influence of a Z bias magnetic field and a rotating XY magnetic drive field. A first portion of the paths are located in control function areas of the chip and a second portion of the paths are located in a storage area of the chip. The period of the permalloy elements in the control function areas is substantially greater then the period of the permalloy elements in the storage area. The thickness of the insulating layer immediately beneath the permalloy elements is less in the storage area than in the control function areas. This difference in thickness is sufficient so that the propagation margins for magnetic bubbles in the control function areas and in the storage area are substantially equal.

Abstract: A conductorless transfer is provided for a large-gap tolerant Permalloy pattern for moving magnetic bubbles. The transfer capitalizes on the symmetry of the elements for enabling a field reversal to achieve transfer.

Abstract: A new geometry for the propagation elements of a field-access magnetic bubble memory is disclosed which is tolerant of relatively wide gaps between elements and lower drive fields. The elements have shapes which define bubble "traps" operative to hold bubbles for relatively high efficiency transfers between elements. In alternate embodiments, the elements have an L-shape or a "pickaxe" shape.

Abstract: A magnetic bubble memory device and a method of fabricating the device are disclosed in which a conductor pattern lies at least between a film for maintaining magnetic bubbles therein, and a soft magnetic material pattern. Further, the magnetic bubble memory device can be formed precisely without suffering from errors due to mask alignment, by employing a mask provided with a plurality of patterns which are different in transmittance.

Abstract: A permalloy-first bubble switch has two curved propagation elements positioned on a layer of bubble domain supporting material. A curved conductor is superimposed on top of the propagation elements so that a current passing through the conductor element permits a bubble to be moved from one curved propagation element to the second curved propagation element.

Abstract: The method of manufacturing predetermined microcircuit conductor patterns, which includes forming on the surface plane of a substrate a layer of insulator material, forming a layer of resist on the layer of insulator material, patterning the layer of resist to define a channel pattern, etching the channel pattern with relatively overwide channels, conditioning the channel bases to receive plating material, and thereafter filling the overwide channels with the plating material to a height at least substantially co-planar with the insulator material to define the predetermined conductor patterns, removing the mask and plated material thereon to uncover completely the conductor pattern.

Abstract: A bubble memory includes a garnet film and a pattern of overlying propagation elements, each made of a layer of permalloy and a layer of manganese. The elements define a plurality of paths for propagating magnetic bubble domains under the influence of a Z bias magnetic field and a rotating XY magnetic drive field. The configuration and positioning of the propagation elements is such that the magnetic bubble domains can be selectively routed, e.g. to bypass defective minor loops, by creating barriers over which the magnetic bubble domains will not propagate. Preselected ones of the elements are preferably heated with a laser beam to a temperature which is approximately 75-90% of the melting point of the permalloy. This diffuses the manganese in the permalloy sufficiently to quench the magnetization in the permalloy to thereby create the barriers to bubble propagation.

Abstract: A technique and structure is described in which bubble domain devices can be made, and particularly bubble domain devices comprisng contiguous propagation elements. A thin magnetoresistive layer, such as permalloy, is blanket deposited over a substrate including a bubble domain film, and is then selectively "poisoned" to destroy its magnetization except in those areas where thin sensors are to be provided. The poisoned portions of the magnetoresistive layer serve as a plating base for conductor metallurgy which can be used as an ion implantation mask, and for carrying electrical current. This eliminates some process steps which had been required in the prior art, and does not leave magnetic permalloy in those areas of the bubble domain chip were they would adversely affect propagation of domains by ion implanted contiguous propagation elements. This technique can also be used to make bubble domain devices having gapped propagation elements.

Abstract: The basic elements of a magnetic bubble device are laminated. A spacer conductor pattern layer is formed on the same plane as a control conductor pattern layer interposed between a magnetic film which forms and holds magnetic bubbles and a propagation circuit pattern layer adapted to control the magnetic bubbles so as to make substantially uniform the distance between the propagation path and the magnetic film.

Abstract: A thin-film bubble domain detection device for use in a magnetic bubble memory comprises two metallic conductor leads formed with sloped opposing edges on the SiO.sub.2 spacer layer of a garnet substrate and a permalloy magnetoresistive sensing element formed therebetween. A method for making the device uses a first photoresist mask in ion milling in a conductor layer to expose an area of spacer, followed by deposit of a permalloy film over the substrate and onto the exposed spacer before removal of the first mask. Extraneous permalloy is lifted off when the first photoresist is removed. A second mask is used to simultaneously ion mill the final conductor lead and sensing element configurations. In one embodiment, first and second dielectric layers are added to the device to improve bubble propagation and provide an easily planned product.

Abstract: An active replicate/transfer magnetic bubble domain switch which is especially compatible with gap tolerant structures is provided. The switch includes a broadfaced corner element of relatively massive structure which retains the bubble domain for more than one field cycle. The switch characteristics are superior to those of existing switches both at the 8 .mu.m and 16 .mu.m periods. The switch offers the advantages of good bias and phase margins, ease of fabrication and reduced drive field requirements. In the 8 .mu.m, version the device requires a substantially lower drive field than the pickax design by virtue of reduced bubble-bubble interaction in the minor loops.

Abstract: Method of fabricating a magnetic bubble memory device in which the magnetizable upper overlay pattern of magnetically soft material, e.g. permalloy, defining bubble propagation elements and bubble function-determining components as located above a bubble-supporting magnetic film is disposed in a wholly planar configuration to avoid bubble propagation anomalies encountered with typical non-planar overlay patterns of magnetically soft material. The fabrication method provides for the consecutive deposition onto a substrate having a magnetic film capable of supporting magnetic bubbles of a layer of non-magnetic electrically conductive material, a layer of insulating material, and a layer of magnetically soft material, such as permalloy.

Abstract: A magnetic bubble circuit and process for the manufacture of same is disclosed in which a pattern of permalloy elements is overlaid on a substantially planar surface contiguous with the top surface of an underlying pattern of conducting elements. This structure is fabricated by including a metal or metal alloy film on the substrate and selectively anodizing the film to produce conducting and nonconducting regions having coplanar surfaces.

Abstract: A close-packed magnetic bubble propagation device includes a pattern having a plurality of propagation elements positioned in at least four adjacent rows. These elements are spaced to provide a period or spacing of bubbles in these rows of less than three bubble diameters. Upon application of a rotating in-plane field to the elements, bubbles in adjacent rows move in opposite directions. A preferred embodiment of this propagation device has at least two storage loops which contain at least four adjacent horizontal rows of propagation elements. A preferred device utilizing this pattern has at least two storage loops and an access path which passes through each of the loops. An electrical conductor is associated with the propagation elements in the access path so that the passing of a current through the conductor together with the application of an in-plane rotating field to the elements causes bubbles associated with the elements in the access path to move along the access path.

Abstract: A magnetic bubble domain storage device comprising a plurality of storage shift registers and at least one major shift register, which serves to provide bubble domains to the storage register and to receive bubble domains from the storage registers. A novel transfer switch, or gate, is located between each of the storage registers and the major register, which is typically configured in the conventional major/minor loop type of storage organization. This transfer switch can be made using single level masking or multiple level masking and is characterized in that the locus of bubble domain propagation paths through the switch element generally defines the letter "Y". These propagation paths are from one arm of the Y to the other arm, from one arm of the Y to the stem or base portion, or the reverse where a bubble domain travels from the stem (base) of the Y to one of the arms of the Y.

Abstract: Guard rails are described for particular use with magnetic bubble domain chips using contiguous propagation elements. These guard rails generally surround the active device area (storage area) of the chip and are used to move stray bubble domains from the storage area to the edge of the chip, or to a collapser etc., and also to prevent stray bubbles from entering the active device area. These guard rail structures are comprised of contiguous propagation elements characterized by an undulating edge and a smooth edge, both of which generally move bubble domains away from the active device area in response to the reorientation of the same magnetic drive field. In one embodiment, the guard rail is a spiral structure surrounding the active device area, having one end in the interior of the magnetic bubble chip adjacent to the active device area, and another end near the edge of the chip, or near a bubble annihilator, etc.

Abstract: A magnetic bubble Y-bar corner for use at the end of a minor loop. The Y-bar corner includes a Y-bar corner element and a canted I-bar positioned between the Y-bar corner element and each of the two adjacent storage elements in the minor loop. The ends of the arm of the Y-bar corner element are positioned adjacent the apex portions of the canted I-bars. The distance between the ends of the arms of the Y-bar is larger than the distance between the opposing ends of the two canted I-bars. With this corner a bubble propagates in either direction along a path from a minor loop storage element to the end of the canted I-bar and then to the apex portion of the canted I-bar and from there across to the end of the arm of the Y-bar.

Abstract: A bubble memory chip is manufactured using the following processing steps:a first dielectric insulation layer is deposited on the epitaxial garnet substrate, next,a comparatively thicker layer of a second dielectric insulator is deposited on the surface of the first layer of dielectric insulation, next,the reverse of the desired conductor image is printed on the surface of the second layer of dielectric insulator using a resist material such as a photoresist, next,a straight wall etching process is used to achieve a straight wall etching of the second layer of dielectric insulation but not affecting the first layer of dielectric insulation, next,the selected conductor material is deposited into the exposed groove from the previous etching process and over any remaining resist material such as a photoresist, next,a resist material is applied over the resulting conducting surface from the previous step, next,a course featured pattern is printed over the desired conductor regions leaving exposed the extensive su

Abstract: The disclosed fault transparent bubble memory has a plurality of minor loops for storing magnetic bubbles, a serial-parallel input path for writing bubbles into the minor loops, and a parallel-serial output path for reading bubbles from the minor loops. Between the parallel inputs and parallel outputs of the minor loops lie pairs of bubble propagation elements. Each element propagates the bubbles by a single predetermined distance. Lying between each pair of these propagation elements is a shorting bar. It converts a pair of single distance propagation elements into one double distance propagation element. Defective minor loops are made transparent by selectively destroying those shorting bars that lie between fault-free minor loops. This selective destruction preferably is performed by a laser beam.

Abstract: A magnetic domain device comprising a layer of a magnetic material for the formation of magnetic domains, for example bubbles, under the influence of a bias magnetic field and a propagation structure with magnetically operating elements for driving the magnetic domains by the sequential formation thereon of preferred positions for the domains. The current conductors used to propagate the domains, either meander conductors or rotary field "coils", are arranged on a layer of silicon, so that the heat developed in the current conductors can readily be carried off by the silicon which exhibits a good thermal conductivity.

Abstract: A magnetic bubble circuit and process for the manufacture of same is disclosed in which a pattern of permalloy elements is overlaid on a substantially planar surface contiguous with the top surface of an underlying pattern of conducting elements. This structure is fabricated by including a metal or metal alloy film on the substrate and selectively anodizing the film to produce conducting and nonconducting regions having coplanar surfaces.

Abstract: A magnetic bubble switch operates in a drive-to-transfer mode when a rotating magnetic field is applied. The switch has a magnetic element in the shape that defines the letter "Y" having two arms and a stem. The switch has at least one serration on the arm of the Y in the vicinity of the stem. The switch has a conductor which is positioned across the end of the stem of the Y. A magnetic element is positioned so as to form a gap with the stem of the Y.

Abstract: A two-dimensional storage system having two dimensional access is described which offers advantages of speed and effective utilization of available storage area. The system is comprised of a plurality of bubble domain storage arrays, each of which has means therein for moving bubble domains in two dimensions. For instance, in each storage array bubbles can be moved either right-left or up-down. A functional area is provided between adjacent storage arrays to accommodate bubble movement to perform read, write, and clear functions and possibly logic functions. In one embodiment, the functional areas are comprised of sensors which simultaneously function as translation elements to map the information in one storage array into an adjacent array. Magnetic bubble domain sensors are provided for detecting bubble domains moved in one or two dimensions. For example, one sensor can be used to detect bubble domains moving right-left while another sensor is used to detect bubble domains moving up-down.

Abstract: These improved current controlled transfer switches are particularly useful for changing the propagation path of very small bubble domains without requiring large amounts of transfer current. The underlying principle is that the transfer operation occurs when the magnitude of the magnetic drive field used to move bubble domains has diminished to a small value, or is zero. This means that the magnetic field due to current in the switch does not have to overcome the effect of the drive field and therefore can be very small while still being effective. This is termed a "start/stop" operation and in one embodiment, current-assisted transfer is achieved by utilizing a change in the sequence of the magnetic drive field (generally an in-plane rotating field) at the time of transfer. In another embodiment, a continuous "three-quadrant" magnetic drive field is used instead of the customary 360.degree. rotating drive field.

Abstract: In a gate arrangement, an information input bubble is deflected from an input path into an output path when moving in proximity of a control bubble on a control path in the interaction zone. T- and I-shaped permalloy elements of the control path pattern are so disposed in the interaction zone to create a very stable control bubble position. At the intersection of the output and input paths the latter is situated at most at three times the nominal bubble diameter from the stable control bubble position. Past the intersection, the input path is as close as one bubble diameter to the control bubble so that the information bubble is necessarily deflected. With the gate layout described a bias margin as high as 11,5% is obtained.

Abstract: Magnetic bubble domain memory circuit in which magnetizable overlay patterns of magnetically soft material, e.g. permalloy, are provided as bubble propagation elements on a bubble-supporting magnetic layer to define major and minor bubble propagation paths. The major bubble propagation paths provide interchangeable bubble input and output sections, and the minor bubble propagation paths are in the form of closed storage loops providing a bubble storage section comprising first and second pairs of blocks. Bubble generators are provided for each of the blocks included in the first and second pairs thereof comprising the bubble storage section, along with first and second detectors and input/output tracks of bubble propagation elements associated with the respective pairs of blocks of storage loops. Swap transfer/replicate gates are disposed between the input/output tracks and each of the storage loops included in the blocks of storage loops.

Abstract: A switch for transferring magnetic bubble domains from one propagation path to another using a magnetic charged wall is described. The magnetic charged wall bridges the two propagation paths and causes the domain to strip out along the charged wall. By pulsing an overlying conductor, the charged wall and the associated strip domain will shrink away from one side of the conductor in order to translate the domain to the other side. In contrast with previous transfer gates using current carrying conductors where the magnetic field produced by current through the conductors served as the major bubble translational force, the present switch utilizes a magnetic charged wall as the driving source, the current through the conductor being used only for modification of the charged wall. Therefore, the switching margins are maximized to be substantially the same as the bubble propagation margins and the switching currents required are reduced from those in previously used transfer gates.

Abstract: A cylindrical domain memory has a storage medium constructed in layer form which is provided with cylindrical domains which are magnetized at right angles to the layer plane, the magnetization being directed opposite to the magnetization of the surrounding material and to that of the magnetic bias field. A propagation structure has an overlay pattern of individual elements of magnetizable material applied in the form of layers to the one layer plane and a rotary magnetic field is directed parallel to the layer plane, which field causes displacement of the cylindrical domains along a path determined by the propagation structure. The propagation structure comprises L-shaped individual elements which are staggered in stepped fashion relative to one another.

Abstract: An improved magnetic bubble domain nucleator is provided which uses a magnetic wall, such as a charged wall, Neel wall, or Bloch wall, to assist nucleation. In a preferred embodiment, a magnetic charged wall is produced in an ion implanted region of a magnetic material with an in-plane magnetic field, and an applied nucleating magnetic field is produced by current in a conductor. The combination of the first magnetic field associated with the charged wall and the second magnetic field produced by current through the conductor is sufficient to nucleate a bubble domain in the magnetic medium whereas each of these fields acting alone is not sufficient for nucleation. Since the first magnetic field provides a component of the total nucleating field, the amount of nucleation current required in the conductor is reduced.

Abstract: A crossover circuit for propagating magnetic domain bubbles in different directions under the drive of an in-plane rotating magnetic field. The crossover circuit includes intersecting vertical and horizontal elements and a pair of L combinations each having a vertical element and a horizontal element. The L combinations are linked to the intersection by a pair of inclined elements. There is also a short horizontal element and a short vertical element linked to the intersection by a second pair of inclined elements.

Abstract: Composite mutually exclusive field-accessed circuit elements common to a plurality of bubble paths. A channel composed of mutually exclusive circuit elements is linked to an adjacent parallel channel of mutually exclusive circuit elements by means of circuit element portions common to both channels. The interconnected channels are operated mutually exclusively by means of corresponding pulsed field sequences. Transfer between the linked channels is via the common circuit element portion. Several new types of propagation circuits are also discussed along with organizations for mutually exclusive major and minor closed loops featuring controlled transfer via common circuit element portions.

Abstract: A magnetic bubble propagation device comprising a pattern of magnetic material formed of the so-called gap tolerant elements, positioned over a bubble supporting material to define a bubble propagation path. Each element of the pattern is spaced from the bubble material such that a gradient is formed in the spacing between the element and the bubble material in the direction of the propagation path. A rotating magnetic field of sufficient strength to magnetize the pattern is applied in the plane of the material and the spacing gradient causes the bubble to move from one element to an adjacent element in one complete field rotation. This device is particularly characterized in that, with the combination of the pattern elements and the spacing gradient thereof, the gaps between the elements are eliminated.

Abstract: A storage device comprising a main magnetic field generator, a rotary magnetic field generator and a number of plates of magnetic material which are arranged transverse to the main magnetic field and in which magnetic domains can be formed and transported along a domain guide structure consisting of discrete element. The domain guide structure comprises a switching device incorporating diverging switches which are arranged according to four orientations which correspond to corresponding orientations of discrete elements of said domain guide structure. The domain guide structures comprise diverging switches which may be arranged to be shifted with respect to each other over one or more discrete elements of the domain guide structure in different plates, each plate having a specific rotary magnetic field sequence.

Abstract: A cylindrical magnetic domain element is disclosed which utilizes a cylindrical magnetic domain (a magnetic bubble) produced by the application of a bias magnetic field to a magnetic sheet of orthoferrite, garnet or the like. Propagation patterns for the cylindrical magnetic domain are composed of a plurality of sets formed on one side of the magnetic sheet and have a multilayer construction with a non-magnetic film of SiO.sub.2 or the like between the layers. This multilayer construction allows for the formation of a propagation pattern having a relatively narrow pattern gap. Further, the propagation pattern is disclosed as having uniaxial magnetic anisotropy, which facilitates the magnetic bubble propagation and ensures retaining of the magnetic bubble.

Abstract: There is disclosed an improved circuit element or structure for use in propagation of magnetic bubble domains. The improved circuit element permits a more desirable gap-to-period ratio than conventional element patterns. The improved circuit element provides portions thereof which are substantially parallel to similar portions of adjacent, similar circuit elements. As a consequence, the magnetic poles developed in the adjacent circuit elements by the application of the in-plane magnetic field are substantially identical at a given time thus facilitating interelement transfer.The circuit element structures are arranged in various propagation paths and operational components. Propagation paths and inter-propagation path elements are described.

Abstract: A large capacity bubble memory device using a basic major-minor loop storage cell design. The basic storage cell is repeated, typically in matrix form, on a suitable bubble domain structure. The cell design is arranged so that interconnecting elements between respective cells permit magnetic bubble domains to be selectively transferred between cells in accordance with the status of switch elements. Control signals control the switch status. The cells include redundancy features so that cells can be interconnected to form a large capacity storage loop whereby chip yield is increased.

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.