Abstract: A thin film transistor array substrate capable of reducing degradation of a device due to degradation of an oxide semiconductor pattern and a method of fabricating the same are provided. The thin film transistor array substrate may include an insulating substrate on which a gate electrode is formed, a gate insulating film formed on the insulating substrate, an oxide semiconductor pattern disposed on the gate insulating film, an anti-etching pattern formed on the oxide semiconductor pattern, and a source electrode and a drain electrode formed on the anti-etching pattern. The oxide semiconductor pattern may include an edge portion positioned between the source electrode and the drain electrode, and the edge portion may include at least one conductive region and at least one non-conductive region.

Abstract: Each device of a family of removable digital media devices may be plugged into a host to permits the host to store data in it or to retrieve data from it. The form factors of the digital media devices and the connector system used by them are compact for minimizing the volume of space occupied in portable devices and for easy storage. Preferably, the digital media devices of the family use serial memory requiring few power and signal lines, so that few electrical contacts are required. For example, a small number of durable contact pads form the contact arrays on the digital media devices, which in conjunction with corresponding contact pads mounted into a suitable socket provide for easy and convenient insertion and removal and for robust and reliable electrical contact over a long insertion lifetime. The digital media devices interface to the host either directly or through adapters.

Abstract: A fatigue resistent ferroelectric element having a ferroelectric body, and regions of enhanced oxide ion mobility on opposite sides of the body to which are attached electrodes. In one embodiment, an element made from the known ferroelectric material PZT is treated at each of two surfaces where the electrodes are to be attached with a fast ion conductor, such as doped yttria stabilized zirconia. In another embodiment, a ferroelectric element constructed essentially of strontium tantalite (SrTaO.sub.6) has each of its surfaces where electrodes are to be attached treated with bismuth oxide (Bi.sub.2 O.sub.3) that is then diffused into surface regions of the element during an annealing process.

Abstract: An integrated circuit includes a layered superlattice material having the formula A1.sub.w1.sup.+a1 A2.sub.w2.sup.+a2 . . . Aj.sub.wj.sup.+aj S1.sub.x1.sup.+s1 S2.sub.x2.sup.+s2 . . . Sk.sub.xk.sup.+ak B1.sub.y1.sup.+b1 B2.sub.y2.sup.+b2 . . . Bl.sub.yl.sup.+bl Q.sub.z.sup.-2, where A1, A2 . . . Aj represent A-site elements in a perovskite-like structure, S1, S2 . . . Sk represent superlattice generator elements, B1, B2 . . . Bl represent B-site elements in a perovskite-like structure, Q represents an anion, the superscripts indicate the valences of the respective elements, the subscripts indicate the number of atoms of the element in the unit cell, and at least w1 and y1 are non-zero. Some of these materials are extremely low fatigue ferroelectrics and are applied in non-volatile memories. Others are high dielectric constant materials that do not degrade or breakdown over long periods of use and are applied in volatile memories.

Abstract: Detection device for a magnetic bubble memory having a detection zone (6) constituted by rows (7) of patterns (8) suitable for the propagation of bubbles in strip form, as well as a transition zone (10) making it possible to draw out the bubbles in strip form. The transition zone 10 has at least one row (18) of soft magnetic material patterns, (18) which has at least one central pattern (22) and a second pattern (24) adjacent to the central pattern (22). The central pattern (22) has a first part (22a) able to guide a magnetic bubble and a second part (22b) able to aid the propagation of a bubble in strip form. The second pattern (24) is able to aid the propagation of a bubble in strip form, while not disturbing the propagation of a bubble along the first part (22a) of the central pattern (22).

Abstract: Magnetic bubble memory in hybrid technology using rows of chevron patterns. The memory detection system has an active detection zone (4) constituted by rows of chevrons, in order to stretch into the form of a strip the bubbles from a propagation path (2), and a first detector (8); a bubble elimination zone (12) constituted by forcing back means (18) for stopping the advance of the bubbles and for forcing them outside the detection system; and a passive detection zone (6) located following the bubble elimination zone (12) and incorporating a second detector (9), to which no bubble must be exposed, in order to eliminate the unwanted signal due to the influence of a rotary magnetic field necessary for the propagation of the bubbles. According to the invention, elimination zone (12) is provided with at least one barrier (20) produced by ion implantation in order to block the passage of the bubbles from active zone (4) to passive zone (6).

Abstract: A magnetic bubble memory has a reading zone with thin detection elements, coated with an insulating layer which carries thick bubble propagation patterns of high magnetic permeability material, and a bubble stretching zone also including thick propagation patterns of shapes such that the rotating field of the device causes the bubbles to progress along the patterns. The device further includes, out of the detection zone, additional thin localized elements of high magnetic permeability material having a thickness much lower than that of the patterns, obtainable by photolithography and located at the same level as the thin detection elements. When located in the stretching zone, the thin patterns are arranged to cooperate with thick patterns so that the voltage well generated by the rotating field of the device has a substantially constant value while moving along the thick patterns.

Abstract: A magnetic bubble memory, in which the PI junction between a first propagation track defined by deposited patterns and a second propagation track defined by the boundary between an implanted zone and a non-implanted zone is defined by an overlap between such propagation tracks, wherein the overlap zone has a surface substantially equal to the surface of a magnetic bubble and forms a stable position for each of the two propagation paths.

Abstract: A bubble memory with a hybrid junction formed between a first propagation track defined by a boundary between an implanted area and a non-implanted area and a second propagation track defined by a sequence of deposited patterns. The overlap zone between the tracks has a surface substantially equal in size to the magnetic bubble. The boundary cleared by the magnetic bubble has a direction perpendicular to an easy magnetization axis of the magnetic material of the memory, and an implanted area is formed beneath one leg of the deposited pattern.

Abstract: A magnetic bubble stretcher comprises a bubble fanning part for propagating a magnetic bubble while gradually stretching the bubble and a bubble propagation part for propagating the stretcher bubble. The bubble fanning and propagation parts include a bubble propagation patterns as fundament elements for stretching or propagating the bubble the bubble propagation patterns in the bubble fanning part are different in shape and/or dimension from the bubble propagation patterns in the bubble propagation part.

Abstract: A high density magnetic bubble memory device comprises first magnetic bubble propagation tracks formed through ion implantation and second magnetic bubble propagation tracks formed of a soft magnetic material. Regions exclusive of those destined for realization of the second magnetic bubble propagation tracks are deeply ion-implanted. Gaps between the adjacent soft magnetic material films are also deeply ion-implanted. The second magnetic bubble propagation tracks may be shallowly ion-implanted or not implanted with ions.

Abstract: A magnetic bubble domain system including a layer of magnetic material in which magnetic bubble domains can be propagated and a bubble domain guide structure coupled to the layer for defining first and second channels for the movement of domains. The bubble domain is injected from the first channel into the second channel at a point where the end of the domain does not experience the isolated end of an element of the guide structure. One implementation of this structure is an arrangement of guide structures so that the direction of propagation in the first channel is substantially perpendicular to the direction of propagation in the second channel.

Abstract: A method for selecting permalloy propagation elements for a magnetic bubble memory is described. The invented method recognizes that propagation characteristics are not symmetrical for a given propagation element. Different propagation elements are fabricated and their propagation characteristics are determined in different directions. Then propagation elements are selected so as to optimize propagation for each direction.

Abstract: An apparatus for controllable propagation of magnetic domains, or bubbles, through an arrangement of closely spaced magnetic propagating elements arranged in an input stage, a strip-former stage, and a decoder stage. Binary logic circuitry results from selective control of bubble movement through alternate paths of elements, with at least one of said paths producing a domain strip extending the full height of the strip-former stage. The decoder stage includes a propagating element spaced apart from the strip-former stage a distance sufficient to prevent propagation of all domains in the strip-former stage except for the full-height strip. The asymmetric geometry of the strip former stage makes the full elongation of a bubble dependent upon which input provided the bubble.

Abstract: In a magnetic bubble memory device comprising a number of magnetic bubble propagation paths each including magnetic bubble propagation bit segments arrayed in the direction of propagation of magnetic bubbles, the propagation paths being arranged in the direction perpendicular to the propagation direction of magnetic bubbles, d/.lambda..sub.x is set to less than 0.2, where .lambda..sub.x is the period of arrangement of the magnetic bubble propagation paths and d is the distance between close adjoining magnetic bubble propagation bit segments of adjacent magnetic bubble propagation paths.

Abstract: In a magnetic bubble memory device comprising a number of magnetic bubble propagation bit segments arrayed to form a magnetic bubble propagation path and having each a pattern of a length L in a direction of propagation of magnetic bubbles being less than 3.4 D where D is the average diameter of the magnetic bubbles and is not greater than 2.0.mu., the height H of the pattern of the magnetic bubble propagation bit segments in a direction perpendicular to the propagation direction of magnetic bubbles is set to be in a range of 0.75.times.L.ltorsim.H.ltorsim.1.1.times.L.

Abstract: A field-access magnetic bubble memory includes an improved expander-detector arrangement. An optimized element shape provides for a constant magnetic field strength at critical points in the drive field cycle. Improved high bias operation results.

Abstract: A magnetic bubble memory has a first bubble propagation track formed with an ion-implanted pattern and a second bubble propagation track formed with permalloy members connected to each other to form a storage loop. The arrangement is such that a position of an attractive magnetic pole created in one of the permalloy members coincides with a position of an attractive charged wall appearing in the ion-implanted layer at a junction of the first and second bubble propagation tracks when a driving magnetic field is in a particular range of direction.

Abstract: An apparatus for controllable propagation of magnetic domains, or bubbles, through an arrangement of closely spaced magnetic propagating elements arranged in an input stage, a strip-former stage, and a decoder stage. Binary logic circuitry results from selective control of bubble movement through alternate paths of elements, with at least one of said paths producing a domain strip extending the full height of the strip-former stage. The decoder stage includes a propagating element spaced apart from the strip-former stage a distance sufficient to prevent propagation of all domains in the strip-former stage except for the full-height strip.

Abstract: A side feed expander for magnetic bubble devices is disclosed. The side feed expander includes a row of expander elements and an input propagation element associated with one of the sides of an expander element in the row of expander elements. In a preferred embodiment, the input element is associated with the apex portion on one side of one of the expander elements. In another embodiment one propagation element is associated with the side of an expander element on one end of the row of the expander and a second propagation element is associated with the side of an expander element positioned on the other end of the row. A side expander permits the dummy sensor to be positioned in several positions, including the opposite end of the expander from where the active sensor is located.

Abstract: A magnetic bubble detector which includes chevron propagation elements and underlying thin film magnetoresistive members is described. A portion of the dummy detection member is misaligned from its overlying chevrons. This misalignment provides a bias to the detection circuitry. A negative voltage is detectable when no bubble is present and a positive potential when a bubble is present. This allows easy matching between the detector and sense amplifier.

Abstract: A magnetic bubble detector according to this invention is constructed of a bubble expander, a bubble detecting element and a bubble sweeper. Moreover, at least the width of soft magnetic material-elements constituting the bubble detecting element as taken in the propagating direction of magnetic bubbles is greater than that of soft magnetic material-elements constituting the bubble expander. As a result, the distances or distance between the magnetic bubble in the bubble detecting element and the magnetic bubbles or bubble in the bubble expander and/or the bubble sweeper increase or increases, so that a magnetic bubble detector of high signal-to-noise ratio is provided.

Abstract: In a bubble memory, propagation elements are configured so that shorts between adjacent elements as a result of fabrication inaccuracies do not destroy their poles and create barriers to bubble propagation. In designing the bubble memory, the gaps can thus approach the resolution limit of the photolithography, resulting in a higher storage density and a reduced operating drive field. In one embodiment permalloy chevrons which overlie a garnet film have opposing side edges defining a gap therebetween which increases in width moving in a direction away from the poles.

Abstract: There is shown and described a magnetic bubble domain device organization using certain propagation elements which have expanded size relative to the remainder of the propagation elements in order to improve device or system operation.

Abstract: Replicate/swap gating circuitry comprising separate gates oriented to be responsive to different phases of an in-plane magnetic field for transferring data to and from an adjacent storage loop in a bubble memory, said gate being formed of magnetic domain propagate elements arranged in propagation paths to perform several independently operable gating functions by a single current conductor on application of current pulses at selected phases of the rotating in-plane magnetic field.

Abstract: A passive annihilator comprising an annihilator element in the form of a spiral located at the end of a path of propagate elements whereby bubbles, entering the spiral element in response to the rotating in-plane magnetic field, will follow the spiral path to its center, and any subsequent bubbles, in a stream of bubbles, entering the spiral will help hold the prior bubble captive in the spiral. The final bubble in a bubble stream under high magnetic bias conditions will be annihilated near the spiral center while the final bubble under low magnetic bias conditions will circulate in response to the in-plane rotating field indefinitely in the spiral, but is not free to escape, and will be annihilated by the entry of new bubbles from a subsequent bubble stream.

Abstract: Consecutive bit bubble memory devices employ a dummy detector element separated from the detector element. This arrangement causes substantial background magnetoresistor noise. The dummy detector of the present invention is located in a novel dummy array which minimizes the magnetoresistor noise, enhances the signal-to-noise ratio and enables the detection of bubble domains without error.

Abstract: A logical operation circuit for performing a desired logical operation by transferring at least one magnetic bubble on a plurality of magnetic bubble transfer routes paths employing chevron patterns, in which two neighboring ones of the magnetic bubble transfer routes provides with a first magnetic bubble transfer section which is formed by narrowed transfer routes or by magnetic bubble elongating means, so that a magnetic bubble transferred through one of the two magnetic bubble transfer routes is stably held across the two magnetic bubble transfer routes of the first magnetic bubble transfer section, while two magnetic bubbles transferred through the two magnetic bubble transfer routes on the two magnetic bubble transfer routes respectively.

Abstract: Input swap transfer/replicate gate and output replicate gate for use in a magnetic bubble memory arrangement between the bubble storage loops and the input and output sections respectively on opposite sides thereof. The input swap transfer/replicate gate and the output replicate gate are of double level construction, each type of gate including a hairpin element at the first level and mounted on a planar layer of bubble-supporting magnetic material on which bubble propagation elements of magnetically soft material are disposed. The bubble propagation elements are arranged to form propagation paths defining a bubble input section, a bubble output section, and a plurality of closed storage loops defining a bubble storage section interposed between the input and output bubble sections. The second levels of the swap transfer/replicate gate and output replicate gate are situated at the input and output ends of the storage loops, forming the opposite bights of the loop.

Abstract: An expander-detector arrangement for a conductor-access, magnetic bubble memory is realized by the inclusion in an electrically-conducting layer in which bubble propagation currents are impressed sets of apertures operative to enlarge a bubble laterally. For this purpose increasingly greater numbers of apertures are arranged laterally with respect to the axis of bubble movement through successive stages of the expander-detector arrangement. The actual detector is formed at the stage including the maximum number of apertures.

Abstract: A magnetic bubble memory structure having an enhanced storage density is made possible by reducing the circuit period, that is the distance between bubbles, in the storage section of the device. This reduction of the circuit period is made possible by using a gap tolerant propagation element, e.g. asymmetrical chevrons. The bubble storage sections are structured such that the areas closest to the transfer gates have a larger circuit period than the remainder of the storage section. The bubble chip architecture utilizing this means of enhancing the storage density may be of the major-minor loop configuration or the block-replicate configuration. Bubble storage sections in the form of loop structures may have a folded loop or an h loop configuration as well as a closed loop configuration. The reduction in circuit period accomplishes enhancement of the storage density without reducing the bubble diameter and other minimum circuit features to achieve this goal.

Abstract: A bubble storage system includes a closed loop propagation pattern suitable for use with a bubble lattice. The closed loop propagation pattern is folded and contains, for example, segments of a hexagonal lattice connected by 60.degree. turns to obtain a close pack bubble storage configuration. The bubbles are propagated along the pattern consisting, preferably, of C-bar or chevron type permalloy elements by a rotating magnetic field in the plane of the pattern. In a preferred embodiment, the folded closed loop propagation pattern is surrounded by a region of non-propagating bubbles retained by permalloy dot confinement means. There are substantially the same number of elements in the propagation pattern as there are bubbles in the lattice that are affected by the propagation elements.

Abstract: A magnetic domain memory in which domains are driven along a structure of discrete elements which includes at least two domain detection elements formed by interconnected chevrons. The detection signal is based upon the magnetoresistive effect of the series of chevrons. The domain detection elements are pair-wise connected to inputs of a difference determining unit. The detection elements of a pair are disposed 180.degree. relative to each other in the plane of the plate, but are otherwise substantially identical. The detection elements are generally asymmetrical in the sense that a majority of pairs of successive chevron elements are interconnected in positions situated between their center and a corresponding end. Thus, upon passage of a domain within a period of the rotary magnetic field, a comparatively large and a comparatively small domain signal can periodically be generated.

Abstract: There is provided a switch which is useful in magnetic bubble domain devices. The switch can be used to replicate, transfer or annihilate any bubble domains in a magnetic bubble domain system. The switch comprises a "BOOMERANG" shaped element which is disposed adjacent to two juxtaposed magnetic bubble domain propagation paths. A re-entrant current path conductor is integrally connected to the boomerang shaped element and associated with at least one of the propagation paths whereby magnetic bubble domains can be stretched, cut, annihilated or the like in response to a control current signal. Optional bar shaped elements are associated with various components of the switch in order to improve the operating characteristics of the switch.

Abstract: There is provided a switch which is useful in magnetic bubble domain devices. This switch can be used to replicate, transfer or annihilate bubble domains in a magnetic bubble domain memory system. The switch comprises a half-disk (or pick-axe) shaped element which is disposed adjacent to two juxtaposed magnetic bubble domain propagation paths.A re-entrant current path conductor is integrally connected to the half-disk element and associated with at least one of the propagation paths whereby magnetic bubble domains can be stretched, cut, annihilated or the like in response to a control current signal.Optional bar elements are associated with the half disk elements of the switch to improve the operating characteristics thereof.

Abstract: There is described a magnetic bubble domain device particularly adapted for bubble domain detection. A bubble is supplied via a standard input propagation path, expanded to an elongated bubble comfiguration and replicated into a plurality of bubbles. The plurality of bubbles propagate along a respective plurality of propagation paths and reach a detector portion, preferrably at different times. The detector portion is arranged to receive bubbles along the respective plurality of paths and to produce enlarged bubbles representative of each of the bubbles replicated from the original bubble. Consequently, the original bubble has been enlarged by elongation and by replication wherein detection of the original bubble is enhanced.

Abstract: A bias field control arrangement for correcting the bias field in accordance with stability range variations in magnetic domain thin film layers. A thin film layer is provided auxiliary to the layers, which auxiliary layer responds to external environmental conditions such as temperature in a manner substantially identical to that of the magnetic domain layers. A pair of register-detectors are defined on the layer in the form of permalloy domain propagating elements, the dimensions of the elements of one being optimized to propagate domains of a diameter larger than that of a domain of a diameter which is optimum in view of the stability range of the layers and the dimensions of the elements of the other being optimized to propagate domains of a diameter smaller than that of the optimum diameter domain. For normal operation, the domains will be propagated along both channels with equal facility and an output comparison section at the output of the detectors produces no control signal.

Abstract: A set of three input, three output bubble logic gates forms all of the possible distinct output functions for conservative three variable gates. The magnetic interaction between single wall domains propagating through separate channels defined by closely spaced circuit element paths causes the domains to switch to or remain on alternate paths via between-path transfer means in a predetermined fashion. In addition to vertically graded element transfer means, several new circuit arrangements are introduced including non-graded elements, strong and weak S-curves, elements having uneven gradation, and other circuit techniques. A group of primitive realizations are described which can be combined to produce other gates having output functions in each of 31 equivalence classes. A methodology for using the gates in logic design is suggested, and several new building block gates producing functions of two variables are presented.

Abstract: A magnetic bubble information writing device in which a conductor loop is disposed on the magnetic bubble propagation circuit and in which magnetic bubbles are generated by sending pulse current through the conductor loop, the device having a means which after having sent the bubble generating pulse current through the conductor loop, sends pulse current for annihilating stray bubbles through the same, the stray bubble annihilating pulse current having a polarity opposite to that of the bubble generating pulse current.

Abstract: A magnetic bubble expander-detector circuit comprising a pattern of magnetic material, forming Chevron elements positioned over a bubble-supporting material to define a bubble expander-detector circuit. 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 expansion and detection. A rotating magnetic field of sufficient strength to magnetize the pattern is applied in the plane of the material and the gradient of the spacing causes the bubbles to move from one element to an adjacent element as the bubbles are expanded and ultimately detected by suitable detection devices. This invention is particularly characterized in that, with the combination of the pattern elements and the gradient spacing thereof, gaps between adjacent elements are eliminated.

Abstract: A switch device which is disposed between adjacent magnetic bubble domain propagation paths to permit selective, substantially concurrent, exchange of information (i.e. magnetic bubble domains) from one path to the other. The switch is a unique arrangement of substantially conventional components which are selectively activated by application of a current through a control conductor. In one condition, the magnetic bubble domains propagate through the respective paths in the normal manner. In another condition, as a function of the control current supplied to the conductor, the bubbles are exchanged (simultaneously transferred) between the respective paths. In yet another condition, the bubbles in one path are replicated and supplied to another path.

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: An on-chip bubble domain circuit organization utilizing a multi-chip concept is provided. One or more storage registers are separately connected to each of a plurality of propagation channels whereby data in the form of magnetic bubble domains (bubbles) may be transferred into and out of the storage registers. Each of the propagation channels includes a generator for producing the initial bubbles which are supplied to a multiple output replicator via an input propagation path. The initial bubbles are replicated into any desired number of new bubbles by a multiple output replicator. The input propagation paths for the several channels have different lengths of propagation times between the generator and the replicator. Input decoders are utilized to determine to which storage register the bubbles from the replicators will be directed along the propagation channel. Those bubbles not selected are, typically, annihilated.

Abstract: A single-level process in which a precision registration process step is replaced by a gross alignment process step in delineation of magnetic and non-magnetic levels in magnetic bubble domain devices. In the instant process, one fine definition and two gross definition process steps are used to define the propagation structure and the fine control conductors simultaneously. This process permits certain fabrication advantages and improved device operation.A compact transfer/replicate switch is fabricated by the new process. This switch permits the transfer of magnetic bubbles between more compactly arranged propagation paths, such as storage tracks and access tracks, in magnetic bubble domain devices and systems.

Abstract: A plurality of stretcher detector segments are connected in series whereby detector signals generated when a bubble passes thereby are added together. Each of the stretcher detector segments is disposed an identical propagation distance away from passive replicators wherein bubbles are replicated from a propagation path and applied, simultaneously, to the stretcher detector segments. The stretcher detector segments are arranged to include both dummy and active portions thereof which are arranged to permit the geometry of both the dummy and active portions of the segment to be substantially matched.

Abstract: A large capacity bubble memory device using a basic 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 transferred between cells. The cells include redundancy features so that the cells can be interconnected to form a large capacity storage loop.

Abstract: Propagation of a lattice of magnetic bubble domains by field access techniques is achieved by using a periodic array of magnetic chevron elements. In response to the reorientation of a magnetic drive field in the plane of the chevron elements, magnetic poles are established to directly drive the lattice bubble domains. Those lattice domains not directly driven by magnetic poles are driven by repulsive forces within the lattice, such as those due to bubble-bubble interactions. The chevron arrays are designed to conform to the bubble lattice framework and patterns are established in which multiple bubble domains are associated with each chevron. The chevron elements can be symmetrical elements or skewed elements, and patterns are provided which can be used to drive multiple rows or columns of bubbles per chevron row or column. Generally, bubble domains alternate between being directly driven by magnetic poles along the chevrons and being indirectly driven by repulsive forces in the lattice.

Abstract: There is described an improved switching device for use in magnetic bubble domain systems. In this device, chevron propagation paths are utilized. A pair of substantially parallel conductors are interconnected at appropriate locations via the chevrons in the respective propagation paths. The pair of conductors permits reduced amplitude requirements in the control current signal. In addition, a return path for the current signal is provided to simplify interconnection in major/minor loop chip configurations. The chevrons are arranged such that the apex of one chevron group is contained between the pair of conductor lines. The ends of adjacent chevron groups in another propagation path are disposed between the pair of conductor lines. Consequently, the magnetic bubble domain "sits" on the chevron ends longer whereby wider phase margins during a transfer operation are achieved. Annihilation of magnetic bubble domains can be achieved by reversing the current direction.

Abstract: A field-access, magnetic bubble memory organized in a major-minor configuration includes an extra set of minor loops dedicated to fault correction. The loops of the extra set are coupled to a major path in a manner to move the information in the loops of the set controllably out of synchronism with respect to the information in the remaining loops. Thus, information in the loops of the extra set can be inserted into the data stream originating from the remaining loops at positions of missing data from faulty ones of those loops.

Abstract: There is described a passive replicator device to be used in magnetic bubble domain systems. The replicator is passive, i.e., does not require an active element such as a current source or the like, and both propagates and replicates bubble domains. In a preferred embodiment, the replicator uses chevron type elements arranged in an appropriate pattern so as to interact with a pair of propagation paths wherein bubble domains are propagated. A bubble in one propagation path is routinely transferred therealong and, concurrently, replicated by the instant device into another propagation path. A plurality of elements arranged in juxtaposition to the chevrons assists in controlling the propagation of the bubbles through the respective propagation paths and, at the appropriate time, provides a cutting action wherein a bubble which is elongated between the chevrons of the two propagation paths is split into two separate bubbles.