CN101273412A - Memory access - Google Patents

Memory access Download PDF

Info

Publication number
CN101273412A
CN101273412A CNA2006800353488A CN200680035348A CN101273412A CN 101273412 A CN101273412 A CN 101273412A CN A2006800353488 A CNA2006800353488 A CN A2006800353488A CN 200680035348 A CN200680035348 A CN 200680035348A CN 101273412 A CN101273412 A CN 101273412A
Authority
CN
China
Prior art keywords
magnetic
magnetic circuits
substrate
data
circuit
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CNA2006800353488A
Other languages
Chinese (zh)
Inventor
鲁塞尔·P·考伯恩
丹·奥尔伍德
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ingenia Technology Ltd
Original Assignee
Ingenia Technology Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ingenia Technology Ltd filed Critical Ingenia Technology Ltd
Publication of CN101273412A publication Critical patent/CN101273412A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11C—STATIC STORES
    • G11C19/00—Digital stores in which the information is moved stepwise, e.g. shift registers
    • G11C19/02—Digital stores in which the information is moved stepwise, e.g. shift registers using magnetic elements
    • G11C19/08—Digital stores in which the information is moved stepwise, e.g. shift registers using magnetic elements using thin films in plane structure
    • G11C19/0808—Digital stores in which the information is moved stepwise, e.g. shift registers using magnetic elements using thin films in plane structure using magnetic domain propagation
    • G11C19/0816—Digital stores in which the information is moved stepwise, e.g. shift registers using magnetic elements using thin films in plane structure using magnetic domain propagation using a rotating or alternating coplanar magnetic field

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Hardware Design (AREA)
  • Computing Systems (AREA)
  • General Engineering & Computer Science (AREA)
  • Mathematical Physics (AREA)
  • Hall/Mr Elements (AREA)
  • Mram Or Spin Memory Techniques (AREA)

Abstract

A magnetic logic device can comprise a generally planar first substrate for an electrical circuit and a plurality of generally planar second substrates for a magnetic circuit, formed in a stacked arrangement over the first substrate. Each said second substrate can have formed thereon a magnetic circuit and each magnetic circuit can have a plurality of logic elements, a data writing element and a data reading element. The data writing element of each magnetic circuit can correspond in planar positioning to a respective magneto-electrical writing element of the first substrate and the data reading element of each magnetic circuit can correspond in planar positioning to a respective magneto-electrical reading element of the first substrate.

Description

Storage access
Technical field
The present invention relates to storage access, but and not exclusively relate to especially and writing data in the magnetic logical device and from sense data wherein.
Background technology
The various data storage devices that multiple storage medium are used for multiple application become available in recent years.Different data storage devices on function at different storage demands.Therefore for some of plurality of optional feature, for example capacity, write/rewrite capability, stability/integrality (having or do not have power supply), size, soundness, portability etc., adopt the various different technologies of data storage.
Known data storage device comprises tape memory, magnetic hard-disk storer and optical disc memory.All all provide the advantage of good memory capacity with relative fast data access, and all can be applicable to writing and rewriteeing of data.All all need the moving component of the form of motor machine or optical reader.This can limit the degree that the equipment that comprises this data storage medium can narrow down to, and the use of limiting device in high vibration environment.Though in each case, surface dielectric is the key of data storage, and the mechanism that relates to also needs the careful control of the character of any support substrate.Therefore, this equipment must have the structure of careful control.And all need reader to have access to equipment surface, the design freedom that this can limiting device.
Other given data memory devices comprise for example flash memory of solid-state electrical storage.These are certain form of EERPOM (Electrically Erasable Read Only Memory) typically, but these suffer to write the problem that persistence and write latency are associated with limited.Especially, before reliability and performance degradation generation, flash memory has the life cycle up to about 1000 write operations.And the write latency height of flash memory is because need the big electric capacity of charging to be used for data storage.In addition, flash memory has about 40Mbit/mm 2(about 25Gbit/in 2) storage density restriction.
Summary of the invention
The present invention considers the problem of conventional system and shortcoming at least in part and creates.
From first aspect, the invention provides a kind of magnetic storage apparatus, it can be operated with storage never has the data that the electric circuit that connects to the direct physical of magnetic storage circuit writes.
From other aspect, the invention provides the solid-state magnetic storage apparatus of a kind of high density.
From other aspect, the invention provides a kind of magnetic storage apparatus that does not have moving component.
From other aspect, the invention provides a kind of use not physical connection to the electric circuit of magnetic storage apparatus data are write method in the magnetic storage apparatus.
From other aspect, the invention provides and a kind ofly respond long-range field generator data are write magnetic circuits element in the magnetic circuits.
From other aspect, the invention provides a kind of magnetic circuits element, its can operate so that long-range field sensor can be from magnetic circuits sense data.
A kind of magnetic logical device can comprise first substrate of the general plane that is used for electric circuit, and second substrate that forms, is used for a plurality of general plane of magnetic circuits on first substrate with stacked arrangement.Each described second substrate can have magnetic circuits formed thereon, and each magnetic circuits can have a plurality of logic elements, data write element and data sensing element.The data write element of each magnetic circuits can be corresponding to each magnetoelectricity write element of first substrate aspect plane positioning, and the data sensing element of each magnetic circuits can be corresponding to each magnetoelectricity sensing element of first substrate aspect plane positioning.Thus, the multi-layered magnetic logical device can be written into and read, and do not need magnetic circuits and related electric read and the write circuit system between be electrically connected.
In some embodiments, logitron comprises at least one data storage elements.Therefore magnetic circuits can be used for data storage.
In some embodiments, second substrate is separated by non-ferromagnetic layer.Non-ferromagnetic layer can comprise the material that is selected from dielectric substance, polymeric material and non-ferromagnetic metal material.Therefore can avoid the interference between the circuit on the different substrate layers.
In some embodiments, each described second substrate can have a plurality of magnetic circuits formed thereon.Therefore can realize highdensity Circuits System.
In some embodiments, magnetic circuits is formed by the nano wire of magnetic material.Each logic element can be by being connected to form between the nano wire, and its function is limited by the geometric configuration that connects.Therefore, single magnetic material can be used for forming a plurality of circuit components, and each has the function that is limited by component shape.
In some embodiments, data write element and data sensing element are the physics discrete components.Therefore can provide the magnetic circuits that compacts.
In some embodiments, the magnetic logical device may further include the magnetic field generator that produces the rotating magnetic field be used to drive magnetic circuits.In some embodiments, magnetic field generator can be operable to and produce magnetic field clockwise and/or counterclockwise.Therefore, be kept in the magnetic circuits data easily mode propagate so that allow easy data locking in the circuit.
In some embodiments, the data write element can comprise the amplification stump of logic NOT door.In some embodiments, the data write element can comprise that coercivity is lower than the circuit part of adjacent circuit part.Can form the circuit part that coercivity is lower than adjacent circuit part and have the geometric configuration different with the adjacent circuit part.Therefore, whole magnetic circuits can be made by single magnetic material, and its function is set up by the geometric configuration of change.
In some embodiments, magnetic circuits can comprise and wipes part.In some embodiments, wipe part each electric part of wiping aspect plane positioning corresponding to first substrate.Therefore, can use special-purpose erasing system to carry out remote wipe.
In some embodiments, in first second substrate magnetic circuits write part and read part can be from second second substrate the writing part and read the part skew of magnetic circuits.Therefore, can avoid interference between the circuit in the different magnetic circuits layers.
Can provide and comprise the data storage device of magnetic logical device as mentioned above.
From other aspect, the present invention can provide a kind of magnetic circuits equipment.This equipment can comprise the substrate of a plurality of general plane that form with stacked arrangement, and each described substrate has magnetic circuits formed thereon.Each magnetic circuits can have a plurality of logic elements, data write element and data sensing element.The data write element of each magnetic circuits can be corresponding to the desired location of each magnetoelectricity write element aspect plane positioning, and the data sensing element of each magnetic circuits can be corresponding to the desired location of each magnetoelectricity sensing element aspect plane positioning.Therefore, the multi-layered magnetic circuit arrangement can be written into and read, and do not need magnetic circuits and related electric read and the write circuit system between be electrically connected.
From other aspect, the present invention can provide a kind of method of making the magnetic logical device.This method can be included on first substrate and form electric circuit, and electric circuit comprises a plurality of magnetoelectricity write elements and sensing element; And second substrate that on first substrate, forms a plurality of general plane with stacked arrangement, each described second substrate has magnetic circuits formed thereon.Each magnetic circuits can comprise a plurality of logic elements, data write element and data sensing element.The data write element of each magnetic circuits can be corresponding to each magnetoelectricity write element of first substrate aspect plane positioning, and the data sensing element of each magnetic circuits can be corresponding to each magnetoelectricity sensing element of first substrate aspect plane positioning.
From other aspect, the present invention can provide a kind of method of making the magnetic logical device.This method can be included in and form first environment division that comprises electric circuit on first substrate, and electric circuit comprises a plurality of magnetoelectricity write elements and sensing element; Form second environment division of second substrate of a plurality of general plane that comprise stacked arrangement on the 3rd substrate, each described second substrate has magnetic circuits formed thereon, and it comprises a plurality of logic elements, data write element and data sensing element; And connect first and second environment divisions, make second substrate be arranged between the first and the 3rd substrate, and make the data write element of each magnetic circuits aspect plane positioning corresponding to each magnetoelectricity write element of first substrate, and the data sensing element of each magnetic circuits aspect plane positioning corresponding to each magnetoelectricity sensing element of first substrate.
From other aspect, the present invention can provide a kind of method that data is write magnetic circuits.This method can be included in the rotating magnetic field in the write element of the data at least position of locating magnetic circuits and modulation magnetic circuits in the rotating magnetic field.In some embodiments, the data write element can comprise that coercivity is lower than the circuit part of adjacent circuit part.In some embodiments, magnetic circuits is not electrically connected the modulation source of showing up.Therefore, magnetic circuits can use electric simple physics scheme to write, and it is made simply and still provides high-performance and packing density.
Inventor of the present invention has developed the magnetic logic architecture of a kind of being called ' domain wall logic ', and it does not use transistor and shows the very little heat that factor causes according to conversion.Domain wall is the moving boundary of aiming at relatively between the magnetized zone.Especially, by soft magnetic material permalloy (Ni for example 80Fe 20) the sub-micron planar nano wire made shown the fabulous conduit that forms domain wall (21-23).The height shape anisotropy of nano wire guarantees to magnetize and preferably aims at the major axis of line.These two kinds possible directions form the basis that binary message is represented, neticdomain wall is as the conversion edge in the variable signal.Domain wall can be propagated the complex network by nano wire under the effect of externally-applied magnetic field.This magnetic field rotates in the equipment plane and as clock and power supply.How previous work can use most advanced and sophisticated shape plane nano line reverse magnetization direction if having shown.Comprise reference in order to provide, hereinafter, logic ' 1 ' is defined as the magnetization of pointing on the domain wall direction of propagation, and logic ' 0 ' is defined as and domain wall direction of propagation opposing magnetization.Therefore, in fact actuating logic NOT operation of tip.Thereby can realize data storage function.
In order to realize any logic function, it is necessary having some other basic functions.For example AND or OR allow to carry out any calculating to replenish the NOT function to add at least one 2 input function.Two routing functions also are essential for complicated logic circuits: produce the fan-out structure of two identical copies of input signal, and allow two signals to pass over each other and not have the decussate texture of interference.In the context of this magnetic circuits structure, the externally-applied magnetic field demand of function should be compatible, makes single overall rotating magnetic field can be applied to entire circuit, and it also is necessary that all difference in functionalitys are operated together.Have been found that this can realize for the architecture that comprises logic NOT, logic AND, fan-out and intersection knot.In addition, provide data to develop and added to the above-mentioned tabulation of element, thereby allow data to write the magnetic circuits neutralization from wherein reading from electronic circuitry involved with the field address data input element of operation thereon to logical circuit.
Concrete and preferred aspect and embodiment are also stated in accessory claim.
Description of drawings
Referring now to appended drawings specific embodiments of the present invention is only described as an example, wherein:
The sketch map provide with the magnetic circuits element of the logic functionality of NOT door equivalence is provided Fig. 1;
Fig. 2 shows that domain wall passes through the sketch map of the motion of magnetic NOT door;
Fig. 3 A and 3B show the sketch map with heteroid magnetic storage circuit;
Fig. 4 A-4G shows the operation of write element in the magnetic storage circuit;
Fig. 5 shows the write element of magnetic storage circuit;
Fig. 6 A-6F shows the operation of the data erasing process of magnetic storage circuit;
Fig. 7 shows the sketch map of multi-layered magnetic circuit arrangement;
Fig. 8 shows the perspective illustration of multi-layered magnetic circuit arrangement;
Fig. 9 shows the schematic plan view of multi-layered magnetic circuit arrangement;
Figure 10 shows the synoptic diagram of rotating magnetic field generator;
Figure 11 shows the synoptic diagram of magnetic storage circuit;
Figure 12 shows the synoptic diagram of magnetic storage circuit;
Figure 13 shows that magnetic opens the synoptic diagram of shift-register circuit;
Figure 14 shows the synoptic diagram of magnetic storage circuit;
Figure 15 A-15C shows the operation of multicomponent magnetic circuits; And
Figure 16 A and 16B show the operation of multicomponent magnetic circuits.
Though the present invention allows various modifications and alterative version, specific embodiments shows as an example in the accompanying drawings and here describes in detail.But, be to be understood that, accompanying drawing and describe in detail and not plan to limit the invention to disclosed particular form, but on the contrary, the present invention plans to cover and drops on as the essence of the present invention that limited by accessory claim and all modifications, equivalent and the alternatives in the scope.
Embodiment
Digital microelectronics is the combination of storer and logic.Basis boolean logic function for example AND, NOT, XOR allows digital IC to make up numeral from storer in arithmetic computation.MRAM uses cmos compatible technology manufacturing, therefore will have semiconductor microprocessors to affect indirectly the microelectronics logic by allowing a large amount of high-speed and high-density nonvolatile memories to embed.The emerging field of magnetic logic manages to redesign the principle of operation of microelectronics logic directly to utilize ferromagnetism in minimum rank.
Attempt (referring to R.P.Cowbum, M.E.Welland, science 287,1466 (2000), G.Csaba, W.Porod, A.I.Csurgay, Int.J.Circ.Theor.Appl.31,67 (2003), and A.Imre, G.Csaba, V.Metlushko, G.H.Bernstein, W.Porod, Physica F 19,240 (2003)) with based on realizing the magnetic logic by the single-electronic transistor architecture of Notre Dame university design people such as (, science 284,289 (1999)) J.Amlani.These schemes that are called the magnetic cell automat are used the network of the magnetic element of magnetostatic coupling.Information is crossed the magnetic soliton of the lattice of interaction magnetic element and is propagated by operation, and by coming the actuating logic function having the node place summation stray magnetic field that clearly limits switching threshold.Be that about one of challenge of this scheme magnetostatic interacting field between the ferromagnetic element is usually than a little less than the demagnetizing field in the element; So any physical imperfection of magnetic element shape stops easily that the propagation of information and equipment become and extremely can't stand manufacturing defect.
The many kinds of magnetic logical scheme based on MTJ have been proposed.In these schemes of a class (referring to people such as G.Reiss, Phys.Stat.Sol.A291,1628 (2004), A.Ney, C.Pampuch, R.Koch, K.H.Ploog, nature 425,485 (2003), and people such as R.Richter, solid-state electronic 46,639 (2002)), information enters logic gate via the electric current in a plurality of bit lines.The what is called of MTJ ' free layer ' will rotate in the direction from the clean magnetic field of combination current, effectively as non-linear summator.This changes the resistance of knot again, and it can be used for controlling the electric current in the bit line subsequently.This scheme has many advantages, and the considerable equipment that is can be programmed by the direction of magnetization that changes reference layer in the MTJ based on existing MTJ technology and logic function.This makes them attractive (referring to Z.Navabi for field programmable gate array (FPGA), DigitalDesign and Implementation with Field Programmable Devices (using the digital Design and the realization of field programmable device) (publishing house of Kluwer institute, 2005)), wherein many different application are used identical hardware; Accurate hardware capability limits by the structure of program storage element.Perhaps in addition more attractive forces be the prospect of quick reconfigurability, because the magnetic hard layer of attributive function can reverse nanosecond, allow hardware self-adapting ground to follow the tracks of the optimal architecture (G.A.Prinz, science 282,1660 (1998)) of ongoing calculating.The shortcoming of these schemes is must change high current density when data change, and this needs high magneto resistive ratio and megacryst pipe.The variation of this scheme exists, wherein the MTJ conventional electrical logic gate (W.C.Black, B.Das, J.Appl.Phys.87,6674 (2000)) that is used for setovering.In this case, MTJ only is used for limiting logic function; Actual computation is carried out in classical electron is learned fully.
Conventional microelectronic integrated circuit (IC) is by the electron stream work of control through transistor switch.Digital signal in IC by the existence of electric charge or there is not expression.It is more that but electronics can provide.Except electric charge, electronics also has the quantum-mechanical nature of spin.But image charge not, spin can have both direction, is called ' making progress ' and ' downwards ' routinely, allows binary digital selection to represent.For example, the magnetization of little ferromagnetic element is the classics restriction of electron spin and is used for for a long time information stores in magnetic recording.In the past decade, many researchers have set up the new technology of spintronics, and wherein electronic spin and electric charge are used for representing the position and carry out data processing in microelectronics IC.This expects to be used for making up lower-wattage, fair speed, the nonvolatile devices of computing technique of future generation usually.
The spintronics development follows diverse ways in semiconductor and magnetics corporations.Semiconductor approach is included in and produces and handle spinning polarized electron in the semiconductor substrate, and information representation is ' making progress ' spin or ' downwards ' spin.At that time, suitably the shortage of room temperature ferromagnetic semiconductor had limited the development of function device, though obtained many progress aspect understanding the spin of using in the optical probe manipulation semiconductor.
The magnetics method of spintronics has followed different paths.Find by metal ferromagnetic/giant magnetoresistance (referring to people such as M.N.Baibich, Phys.Rev.Lett.61,2472 (1988)) that non magnetic multilayer shows afterwards, for example nickel, iron and cobalt are developed many room temperature equipment to the researcher by using feeromagnetic metal.Information is represented by the direction of magnetization in the little ferromagnetic element in these equipment.A kind of this equipment that is called MTJ (MTJ) forms the building block of magnetic RAM (MRAM), a kind of non-volatile, high density, high-speed memory technology are (referring to people such as G.Grynkenich, MRS Bulletin 29,818 (2004)).In addition, the nearest of spin momentum transfer effect proved (referring to J.C.Slonczewski, J.Magn.Magn.Mater.159, L1 (1906), L.Berger.Phys.Rev.B 54,9353 (1996), J.A.Katine, F.J.Albert, R.A.Buhrman, E.B.Myers, D.C.Ralph, Phys.Rev.Lett.84,3149 (2000), people such as S.J.Kiselev, nature 425,380 (2003) and W.H.Rippard, M.R.Pufall, S.Kaka, S.E.Russek, T.J.Silva, Phys.Rev.Lett.), wherein magnetization is directly operated thereon by impressed current, arrives this exciting field by the further heat that increases of new interface mechanism between the electronics and the magnetics world is provided.Inventor of the present invention is working with expansion magnetic nonvolatile memory always, is the essential element of feasible magnetic logic technology development.
So apparently, electronic spin and electric charge all are used for the spintronics field of logic and memory operation and can use the technical foundation that is different from conventional semiconductors electronics that logical device is provided.Use these technology, can use the plane magnet-wire structure complete logic architecture of width less than micron.Logic NOT, logic AND, signal fan-out and signal cross element can be constructed to have simple geometric design and can use together in single circuit.The other element permission information of data input writes the neticdomain wall logical circuit.
Use technology that so-called nanometer magnet forms so-called magnon cellular automaton (MQCA) equipment at Cowburn and Welland, discuss among the science Vol 287 pp 1466-1468.Utilize this technology, the circuit of magnetic circuits element and this element of use is discussed in International Patent Application PCT/GB01/05072 (WO02/41492) and PCT/GB03/01266 (WO03/083874).Therefore, there is existing Knowledge Base aspect the ball bearing made using of these elements making the magnetic circuits element based on the disclosure of these papers and patented claim and use.
In the context of this example, a kind of NOT of being door of the circuit component that in the magnetic storage circuit, uses, as shown in fig. 1.The NOT door 10 of this example can perhaps be made of the nanometer-level plane magnet-wire the chain of the nanoscale point of magnetic material.The arrow that shows among Fig. 1 represents to form the direction in magnetic field in the arrowband material of NOT door.The ultimate principle of the operation of NOT door 10 is that the magnetic field domain wall that enters is propagated by door, and the magnetic direction counter-rotating takes place when the domain wall process is followed the tracks of pattern.Therefore, the physical influence by the magnetic direction counter-rotating provides logic NOT door function.
In the use, door is arranged in the magnetic field that vector rotated on the equipment plane along with the time.Because magnetic shape anisotropy, the magnetization in the line limit the major axis that is positioned at along line usually.Therefore, in most of the cases, there are two kinds of magnetization possibilities, can realize that the traditional binary of data is represented.The change of direction of magnetization is by being regulated along the neticdomain wall of line sweep by impressed field in the line.The fact of magnetic field rotation means and can transmit domain wall around corner.
The operation of NOT door 10 and the more details of structure are showed in WO03/083874 (Cowburn), quote its full content as a reference at this, therefore here further do not discuss.But the ultimate principle of the operation of NOT door is clearly.
In the example below, can use and similar NOT door structure unit or multidigit memory circuit shown in Fig. 1.The NOT door that uses in these circuit has cycloid shape.Door can be by the thick permalloy (Ni of 5nm on the silicon substrate 80Fe 20) the focused ion beam grinding of film makes.Fig. 2 provide cycloid commutation action explanation and show how the delay of a semiperiod exists between input variable condition and output variable condition.
Under the downfield condition, the direction of magnetization in the sub-micron ferromagnetic in-plane line trends towards major axis along line because of strong magnetic shape anisotropy.When meeting in the magnetization of two opposite orientation is online, rearranging of atomic magnetic moment is not unexpected in succession, thereby but domain wall takes place to form gradually on certain distance.
Now known by with the applying of the magnetic field of line parallel, domain wall can be propagated along straight line sub-micron magnet-wire.In this example, can apply magnetic field, thereby propagate domain wall along the magnet-wire that also changes direction and turn with the vector that in sample plane, rotates along with the time.Clockwise or be rotated counterclockwise and limit the magnetic field chirality.Domain wall should be propagated around the magnet-wire corner, supposes that magnetic field and corner have identical chirality.But the chirality of corner depends on the direction that domain wall is propagated, and makes that domain wall will only can pass through given corner in one direction in the rotating magnetic field of given chirality.This satisfies the important need of any flogic system that clear and definite directions of signal flow must exist.Two stable magnetization direction in the sub-micron magnet-wire provide the natural method of two boolean logic state of expression, and the basis of the operation of this each logical block that becomes memory device with applying of rotating magnetic field.
The NOT door was functional when cycloid illustrated in fig. 2 provided commutation function and explanation in being in suitable rotating magnetic field.Suppose that magnetic field rotates in the counterclockwise direction.The domain wall 20 that arrives the terminal ' P ' (referring to Fig. 3 B) of knot will be propagated (referring to Fig. 3 C) around first corner of knot, and along with magnetic field rotates to vertical direction by arriving terminal ' Q ' from horizontal direction.Magnetization between ' P ' and ' Q ' will be continuous (referring to Fig. 3 D) now.Then, along with magnetic vector continues towards opposite horizontal direction rotation, domain wall 20 should be propagated (referring to Fig. 3 E) around second corner of knot, leaves away and recovers continuous magnetization between ' Q ' and ' R ' at terminal ' R '.Compare with the line before being located immediately at knot, the magnetization that is located immediately at knot line afterwards should be reversed now.Therefore, this knot should be with the NOT function of half magnetic field cycle propagation delay carry out desired.This operation is similar by carrying out 3 its directions of rotation counter-rotating with automobile.
Therefore in domain wall arrival input with from there being the total delay of half period between output is left.In the example below, get back to input, realize the memory function that is associated with this synchronization delay by a large amount of magnetic NOT doors being cascaded then the output of chain is carried.
As shown in Fig. 3 A, many these cycloid tips can be joined together to form the shift register 30 of multicomponent, function cocycle.By on direction A rotating magnetic field being applied to whole shift register 30, the domain wall in the shift register 30 will drive around shift register on the sense of rotation of magnetic field.Therefore, the shift register 30 of this example comprises loop-coupled many cycloids tip 32.Shift register 30 also can comprise data input element 33 and data sensing element 34, its each will discuss in more detail below.
As discussed above, data loop is arranged in the magnetic field that vector rotated on the plane, loop along with the time.In this example, this rotation has the frequency in the 1Hz-200MHz scope.Magnetic field amplitude can be constant along with the magnetic field rotation, thereby forms the circular trace of magnetic vector, and perhaps it can change, thereby forms the elliptical path of magnetic vector.This can make below the loop exchange current through strip line and realize in small size equipment by the electromagnetism strip line is placed on then.In larger area equipment, the substrate in carrying loop is arranged in the quadrapole electromagnet.
Magnetic field amplitude should enough can be pushed through each NOT door with the assurance domain wall by force on the way, but can be so strong so that can irrespectively assemble new domain wall with scanning machine system.
Promoting domain wall regulates by the width and being used in thickness, the loop magnetic material of making the loop that the required magnetic field of each NOT door can be by changing the loop.This magnetic field should be enough big so that equipment can not suffer wiping from spuious environmental magnetic field.If it is a problem that stray magnetic field is wiped, can use Mumetal shielding the present invention.In one group of example, can use the best externally-applied magnetic field intensity in 50-200 Oe (3980-15920A/m) scope.
Alternatives about the relative position of the data input element 33 of shift register and data sensing element 34 shows in Fig. 3 B.When circuit component position control principle behind is the hand facility of element, can produce many this alternative configurations, make all in single rotating magnetic field, operate together collaboratively.
In the circuit of this example, a data bit is stored by two circuit components.Each circuit component with domain wall from circuit component begin to be sent to the output of circuit component the time have half period delay.This storage effect allows to carry out data storage by circuit.In the context of Fig. 3 A and 3B, each of NOT door 32 (comprising data write element 33), the fan-out of sensing element 34 knot, and each regards circuit component as to tie relative flush end with fan-out.Therefore, the circuit that illustrates in each of Fig. 3 A and 3B is 5 (10 circuit component) shift registers.
The magnetic circuits that uses the odd number circuit component to form the type is possible and feasible.But should be noted that in sort circuit each data bit centers on each complete rotation of circuit by this and reverses.Therefore, in some applications, follow the tracks of at any given time circuit " even number " still be " odd number " on the cycle operation may be necessary, to avoid after data are read, the causing data reversal of losing destruction.Use the even number circuit component, this data reversal does not take place, thereby period tracking is unnecessary.
Show about more the going through of the operation of shift register referring now to Fig. 4, comprise the operation of data write element 34.In the figure, be given in the example of the ball bearing made using of constructing on the nanoscale.The direction Hx of magnetic-field component and Hy, the position that the direction (Rot) of magnetic field rotation and MOKE measure ( *) indication in the figure.
Hereinafter, term " level " and " vertical " when using for magnetic field amplitude, refer to scheme as shown the field intensity on x and the y direction respectively.Circuit need not remain on the particular order direction in order successfully to use.
Those skilled in the art will recognize that, be used for storing or the circuit of deal with data must be able to receive data from the external world.Fig. 4 A shows 5 magnetic circulating register structures that comprise eight NOT doors and fan-out knot.In this circuit, the stump zone, center (stub region) that of NOT door has an amplification to be reducing the coercivity of line, thereby reduces to cause the necessary intensity of the externally-applied magnetic field of magnetization inversion, and making becomes data input element 33.Stray magnetic field from current can be used for magnetic data directly and is partly write amplification stump (enlarged stub).But at this example, design stump (stub) makes data is write the opereating specification that wherein required magnetic field amplitude is positioned at other NOT doors and fan-out knot.Therefore, it is possible writing data by the amplitude of modulating the rotating magnetic field that the overall situation applies.Rotating magnetic field is therefore simultaneously as power supply, clock and serial data channel.
Fig. 4 B-E shows the principle of work of data input element in the magnetic field that turns clockwise.From initial magnetization state (Fig. 4 B), magnetic field H significantly x WriteAssemble domain wall in element, it is propagated by NOT door knot and along input/output line and is divided into domain wall DW1 and DW2 (Fig. 4 C).Domain wall DW1 centers on same hand corner transmission easily along with the impressed field rotation and will continue to propagate (Fig. 4 D) around shift register.On the contrary, domain wall DW2 initially around and impressed field rotation mutually backhand easily corner transmit, so along with magnetic field is further rotated, necessarily reverse its direction and pass through NOT door (Fig. 4 D) backward of domain wall.At the NOT door, the domain wall that returns necessarily is divided into two once more.A part will be propagated along the output arm (Fig. 3 E) of NOT door knot, and after original domain wall postpones half period, and another part will be propagated to recover initial magnetization state (Fig. 4 E) backward along the data input element.In order to prevent the destructive vibration condition of possibility, design element 33 makes this return domain wall and eliminates when arriving element end.Therefore, the output from the data input element 33 of this sequence with single assembly incident is a pair of domain wall.
As shown in Figure 5, can have the physical size of selecting for the residue element with respect to circuit causes must reducing of reversing magnetic field intensity as the write element 33 that uses in the example circuit of in Fig. 4 A, describing, and the desired characteristic of eliminating the domain wall that arrives stump.In this example, whole element has the about 3 microns total length from the knot in input and output signal path to stump.This is divided into length is that 225nm and length are the initial part of 500nm, is that 200nm and length are the narrowed portion of 350nm succeeded by width, grows and reach the broadening part of 325nm width succeeded by 1 μ m.Next the long part of another 1 μ m keeps the width of 325nm, and final stump forms the long blunt end of about 300nm.These physical sizes have been presented in the circuit that illustrates among Fig. 4 A and have worked, and wherein width and all corner of magnet-wire with 200nm has the radius-of-curvature of 1 μ m.
Sense data is the problem that magnetic field sensor is aimed at fan-out sensing element 34 from shift register.Along with each domain wall by rotating magnetic field around drives, for example domain wall is through fan-out, domain wall is divided into two, continuation is around circuit and another transmission enters sensing element 34.This magnetic direction in the sensing element 34 is identical with field direction in the appropriate section of circuit.As write element 33, the stump of sensing element is shaped so that eliminate domain wall, thereby prevents that destructive vibration condition from taking place.
The data that the external signal that shows among use Fig. 4 F is carried out in the shift register write.5 bit sequence example write field patterns once apply to use 5 bit data to fill shift register, and only the part between the dotted line is carried out data and write (the last magnetic field cycle is used for guaranteeing that all domain walls correctly enter the shift register loop).Before ablation process, eliminate all domain walls by applying the low amplitude rotating magnetic field.For write the individual data position in the circuit of this example, the range weight of a semiperiod in magnetic field is H x Write=138 Oe (10984.8A/m) and Hy 0=50Oe (3980A/m) makes the magnetic data input element change as mentioned above.The magnetic field condition that does not write data is H x No-write=90 Oe (7164A/m) and Hy 0=50 Oe (3980A/m).In its initial configuration, use H x 0=90 Oe (7164A/m) and Hy 0The shift register MOKE of=50Oe (3980A/m) (magneto-optic Kerr effect) measures and confirms not exist domain wall (Fig. 3 G, trace I).After single the applying of write field pattern, shift register comprises several two domain wall bags, the binary data stream of its expression ' 11010 ' (Fig. 3 G, trace II).Notice that in this case low MOKE signal is corresponding to logic ' 1 ', because 180 ° of rotations between input element and the sense wire.This data stream is ideally corresponding to the data stream in the write field pattern (Fig. 4 F), and confirms the principle of aforesaid data input element.
Under experiment condition, correct bit sequence is returned in one hour delay between writing and reading, and proves the intrinsic non-volatile of shift register.But the final storage at room temperature time is in fact considerably beyond one hour, and can the design lines width and thickness to guarantee that the data holding time was above 10 years.All information in the whole shift register can be passed through amplitude H x 0The single removal that applies of wiping the half-sinusoid magnetic field pulse of=243 Oe (19342.8A/m) and 1.85ms pulse length uses ten domain walls to fill shift register (Fig. 4 G, trace III) at once, and no matter the initial magnetization arrangement.
Therefore now described the example of complete feasible and available magnetic circuits shift register, the selectivity by the magnetic drive signal changed applies, its can be written into with data storage in wherein.Data can be by reading with the magnetic field sensor of given signaling bearer element alignment.This circuit can be by the NOT function removal or interpolation reduce or expand, to preserve the data bit of arbitrary number.The magnetic storage circuit with read and write circuit (it can be traditional electrical circuit) between interface do not need to have direct physical and be connected because these functions can use can indirect operation and the magnetic field of sensing carry out.
In an example, relative with the fan-out of data sensing element 34 removing end 35 can be used for the selective data deletion.Fig. 6 A-F illustrates this process about the example shift register of describing with reference to figure 4 in the above.In this example, suppose that each data element has been loaded with domain wall in advance.In order to carry out selectively removing, from horizontal component ofmagnetic field is zero (to make each NOT door and fan-out have domain wall at their input end, and also have domain wall removing end) the position begin, the driving magnetic field of change circuit during the first half in cycle, so that make the domain wall of removing on the end move and eliminate, thereby delete their previous information of preserving with another domain wall collision.The driving magnetic field of change illustrates that in Fig. 6 A it is presented at the horizontal magnetic field amplitude that the first half reduced in the cycle.This underswing that reduces enough makes domain wall propagate by toe-in, so all domain walls pinned (pinned) at NOT door and fan-out knot place and not mobile.But amplitude is enough big so that domain wall is propagated along removing end, does not have the toe-in that need pass through there.Therefore this domain wall propagates into next memory element (when it is unique mobile domain wall) during the first half in cycle.Back during half in the cycle, two domain walls collisions in the identical memory element and eliminating mutually, so deleted data.This shows in Fig. 6 B, and data bit is deleted there is clearly.
The continuous application of this process shows in Fig. 6 C-F, and wherein in each continuous figure, another domain wall is to deleted, thus the ground selectively removing of the data in the shift register.Should be appreciated that this deletion can non-ly sequentially apply, make some data bit can preserve and other deletions, no matter they are around the relative position of shift register.
Only take place in a zone of shift register because domain wall is eliminated, domain wall ratio to be deleted must move in this zone.Wipe second full field cycle of magnetic field pattern by turn and propagate all domain walls, and do not have domain wall to eliminate through two memory elements.This " foundation " next domain wall to be eliminated is right.Do not eliminated if this time is a pair of, then can apply " normally " drive signal should be to passing through scratching area to move.
The deletion that should be appreciated that domain wall should begin when the correct symbol in horizontal drive magnetic field.When using correct symbol, the domain wall of elimination is those of description stored data bit, does not influence any other data in the register thereby the permission data bit is deleted.But if the symbol of horizontal magnetic field is incorrect, then Shan Chu domain wall will be each one from two stored data bits, but therefore two this positions all will be destroyed any one all intactly delete.In order to correct this situation, can wipe register (just deleting all data) and write data again, perhaps new data can be written to the influenced position in the shift register.
This effect also can be by whole halt circuit driving magnetic field, make domain wall in circuit, keep static and produce.Then, the end generation is being removed so that move single domain wall along removing end in local orientation magnetic field.Because in not having other domain walls to be at that time to move, the domain wall that moves will be in the other end of removing end and domain wall collision, cause that mutual domain wall eliminates, thereby deletion is by the data of this domain wall to preservation.This local magnetic field applies and can use long-range magnetic field production process to apply, to write the identical mode of data with using data write element 33.
And in alternate example, the selective data delete procedure that outlines above can instead be used for ablation process.In this pattern operation, circuit pre-loaded complete " 1 ", and can be by using overall magnetic field mobile data sequence by circuit, and stop this magnetic field and write with the selectivity of in the Data Position of needs, carrying out " 0 ", use selectively removing to write " 0 " in the position of needs.
(electrical circuit) is the same with conventional electrical circuit, and a plurality of magnetic circuits (magnetic circuit) can be formed on the single substrate side by side.Each circuit can be read out and write independently as mentioned above.Optimum balance in the number in loop and each loop between the number of NOT door will be sought for given application.Each comprises that a small amount of loop of a large amount of NOT doors is integrated into and will be very easy in the encapsulation and cheaply, if but single NOT door fail by manufacturing defect, will tend to the fault of entire equipment.This combination also will have long data time, because must wait for that average a large amount of clock period is so that given data block is recycled to read-out position.Each comprises that a large amount of loops of small amount of N OT door will have resistibility (loop that comprises failure door can take out and reduce indistinctively whole memory capacity) for the fault of each NOT door very much from circuit, and will have fast access time, go out and write point (thereby on higher cost and the substrate lower packing density) but will introduce mutiread more, and integrated a large amount of loop is more complicated in the single integrated circuit encapsulation.All figure in the document show the loop of 8 doors.This signifies that in fact purely each loop can comprise the door of any number from several to thousands of doors.
Except placing a plurality of circuit on single layer, magnetic circuits discussed above also can form in a plurality of layers as shown in Figure 7.Here, can make many substrate layers 40, each has one or more magnetic circuits 42 formed thereon, thereby produces high density magnetic circuits equipment.In an example, multi-layer device can be by each substrate layer of deposition, and is followed successively by every layer before the next substrate in deposition and produces circuit and form.Layer of material can be deposited between the circuit carrying substrate layer to separate the magnetic circuits in the different layers.In an example, this storeroom is apart from providing the interlayer spacing of about 20nm to prevent the magnetostatic coupling between the circuit on the different layers.The material that separates these layers can be any nonferromagnetic material.Suitably the example of material can comprise dielectric substance, polymeric material and nonferromagnetic material.In some instances, parting material is the material that can easily deposit in based on the manufacturing process of layer.
With reference now to Fig. 8,, be presented at the example that individual layer electrical circuit system (for example cmos circuit) goes up the multi-layered magnetic equipment that forms, the electrical circuit system provides reading and write-in functions for the magnetic circuits in all layers of equipment.
As shown in Figure 9, silicon substrate 50 can have many electrical circuit elements 51 formed thereon.These can take to be designed to produce the element that extends to the magnetic field outside substrate 50 planes, and the form that is designed to detect the magnetic field sensor of substrate 50 plane external magnetic fields.
Magnetic field generator for fear of given circuit writes another circuit, and the generator and the corresponding data write element that are offset different circuit are necessary.Similarly, read out data from the data sensing element of wrong circuit for fear of magnetic field sensor, the sensor and the corresponding data sensing element that are offset different circuit are necessary.Required side-play amount depends on many factors, comprises the number of plies in the equipment.For 50 layers of equipment and interlayer spacing is the example of 20nm, and the distance from electronic circuit to the magnetic circuits of going up most approximately is 1 μ m.Therefore the field intensity that is produced by generator need be enough to have effect with electronic circuit at a distance of this distance.The situation that extend on all directions comparably in this magnetic field that is normally produced by electronics or electric circuit.Therefore, for fear of the interference between different generators and sensor and the magnetic circuits except that their respective magnetic circuit, equal at least that the about side-play amount of twice maximum effect radius normally advises.In some cases, if the power of each generator/sensor for it must write/sense data the layer particularly the design, can realize lower side-play amount.In some examples of 50 layers of equipment, the spacing in the zone of 5-10 μ m can be used to provide the balance between noiseless and the current densities.Higher side-play amount can be used in other examples.
Being formed in the layer on the silicon substrate 50 is many magnetic circuits layers 40, and each has and is formed at one or more magnetic circuits 42, and is separated by dielectric layer 41.Each magnetic circuits 42 comprises write element 33 and sensing element 34.For each magnetic circuits in the equipment, write element 33 and sensing element 34 are located immediately at the difference magnetic field generator and the magnetic field sensor top of electrical circuit layer 50.In order to make each magnetic circuits to write independently and to read, each magnetic circuits has not write element or overlapping write element 33 and the sensing element 34 of sensing element with any other magnetic circuits.
The magnetic circuits element further specifies with respect to being aligned among Fig. 9 relatively of electronic circuit component, and its expression sees that by magnetic circuits layer 40 plane of the equipment on the electrical circuit layer 50 penetrates.As seeing from Fig. 9, the magnetic circuits 42a on the first magnetic circuits layer (showing with solid line) has write element 33a that aims at the magnetic field generator 52a of electrical circuit and the sensing element 34a that aims at the magnetic field sensor 53a of electrical circuit.Similarly, the magnetic circuits 42b on the second magnetic circuits layer (showing with dotted line) has write element 33b that aims at the magnetic field generator 52b of electrical circuit and the sensing element 34b that aims at the magnetic field sensor 53b of electrical circuit.Therefore the multi-layered magnetic circuit can be arranged on the same area of electrical circuit, as long as the part of reading and write of magnetic circuits is offset each other.
Therefore, can encourage the magnetic field generator of electrical circuit to change the rotating magnetic field that is applied to entire equipment partly independently.By this method, the part change that single rotating magnetic field can be applied to entire equipment and can carry out magnetic field is written in magnetic circuits 42 more selected to allow data.Similarly, when expectation from given magnetic circuits during sense information, thereby can encourage the sensing element 34 corresponding magnetic field sensors with this circuit that data are read into the electrical circuit from magnetic circuits.
The selective erasing function of describing in the above with reference to figure 6 also goes for as Fig. 7 the multi-layer device that shows in any one of 8 or 9.This can act on all circuit globally or can carry out partly based on each circuit or every group of circuit.Under the situation that a plurality of circuit are driven by common rotating magnetic field, can realize being used for the change driving magnetic field of selective erasing partly, thereby not need to wipe the data of all circuit in the self-magnetic field.When expectation is wiped, cause that the drive signal of deletion is applied to entire equipment.But, for the circuit that does not need to delete, the electrical circuit element that can encourage on the electrical circuit layer suitable location " to fill it up with " for those circuit thus magnetic field guarantees domain wall normally propagates around circuit.As selection, can be by stopping driving magnetic field and using the electrical circuit element of suitably aiming on the electrical circuit substrate 50 to provide the drive signal of part intensity to handle this deletion with mobile domain wall to the removing end of circuit.
Therefore, the example that can use single electrical circuit layer to write and read the multi-layered magnetic memory device of multi-layered magnetic memory circuit has been described now.Therefore, it is low that the production cost of equipment can keep, because do not need to be formed into directly being electrically connected of each magnetic circuits layer.
By adopting this a plurality of layers that have, each has the strategy of a plurality of data storage circuitries, can realize very high storage density.For example, the size of circuit of using in the example of Fig. 4 above using, and 50 magnetic circuits layers in the hypothesis equipment, packing density is up to 16Gbit/inch 2(about 25.4Mbit/mm 2, use 1mm 2=0.00155inch 2Conversion).If the width of magnetic circuits track is decreased to 90nm (and radius-of-curvature correspondingly is reduced to 450nm), this packing density can be increased to 77Gbit/inch so 2(122Mbit/mm 2).Can see, can use little physical equipment to form the very memory device of high power capacity.
Though described abovely can make multi-layer device, can use other manufacturing technologies by deposition magnetic circuits layer on the substrate that is formed with electronic circuit.For example, for fear of the necessity of magnetic material being introduced in the electronic circuit manufacturing equipment, individual equipment can be made and be assembled into to electronic circuit substrate and a plurality of magnetic circuits layer individually.Therefore electronic circuit can be formed on silicon (or other semiconductors) substrate, and is known as routine.In independent manufacture process, can be based on substrate, for example silicon or other Semiconductor substrate are made the magnetic circuits layer as mentioned above.In this process, will stop as layer away from electronic circuit near the layer of substrate.After this two parts manufacturing, they can be assembled and make the substrate of magnetic circuits layer at the far-end of electronic circuit substrate.Can use any suitable fixing means to realize two-part assembling.In an example, can use and apply pressure to two substrates and make them force together mechanics fixing means.In another example, can use based on producing the fixing means of vacuum between two parts so that they are fixed together by being pumped in.Therefore, can see that many kinds of manufacture methods can be used for producing the multi-layered magnetic circuit arrangement.
Now, with reference to Figure 10, the example of the structure that produces rotating magnetic field will be shown.In this structure, a pair of coil 61 and 63 is arranged with cross conformation, and the track of each coil substantially perpendicularly intersects.Therefore by applying alternating signal, can produce rotating magnetic field to coil.In this example, use cosine waveform signal Iy drive coil 61 at 62 places, and use sine wave-shaped signal Ix drive coil 63 to produce rotating magnetic field in the part that coil intersects at 64 places.Relative phase sinusoidal and cosine signal is determined the direction of magnetic field rotation.Therefore, the magnetic circuits that is arranged in the volume vertical with indicating area 65 will be driven by the rotating magnetic field that produces.As shown in Figure 9, thus the coiler part that does not form the part of intersection region can spatially compact and reduces the overall dimensions of magnetic generation circuit.
Should be appreciated that and to use the alternative approach that produces rotating magnetic field.A kind of standby selection is to use the strip line on the electronic circuit substrate for example to produce rotating magnetic field.These can use sinusoidal as discussed above and cosine wave (CW) drives.This signal based on strip line produces and can be used for producing rotating magnetic field into entire equipment.In other examples, can use multiple magnetic field generator scheme to produce different rotating magnetic fields as the zones of different of equipment.Therefore, frequency drives that the zones of different of equipment can be different and/or access asynchronously.During the zone that is driven by the different rotary magnetic field generator can comprise every layer more than a circuit, circuit in every layer, only single circuit in the perhaps single layer.In this last example, rotating magnetic field generator can be used for carrying out data writing to circuit by the direct modulation of rotating magnetic field rather than by using independent local generator to carry out magnetic field modulation for writing.
Realize equipment by for example using by the many magnetic circuits in the rotating magnetic field of the circuit generation that shows among Figure 10, and by with reference to figure 7-9 in the above by drive the many magnetic circuits many layers from single electrical circuit with discussing, it is possible producing the equipment that nucleus that all heater elements are positioned at equipment periphery and equipment produces considerably less used heat.Therefore, the magnetic circuits equipment that forms according to these principles can be operated and not have because of inadequate cooling provision risk of overheating.In great majority were used, the equipment of Zhi Zaoing can be operated and continuously without any need for effective cooling by this way.
Therefore, a kind of system, apparatus and method that are used to form the magnetic circuits equipment that can remotely drive, write and read have been described now.Therefore, can use not have and form the high density data memory device to reading of equipment with the magnetic circuits element that directly is electrically connected of write circuit.And data can optionally be deleted in the slave unit, and do not need directly being electrically connected between erasing circuit and the magnetic circuits.Therefore the manufacturing cost of equipment can keep low because there be not essential being electrically connected.And, use the equipment of this magnetic circuits to make very for a short time and a large amount of logic gates still are provided.
The alternative circuit structure that can be used for making the magnetic circuits that is suitable for using in magnetic apparatus is described referring now to Figure 11-14.
Figure 11 shows that the crooked stump that uses the NOT door provides simple (2) shift register of data writing capability.This scheme need be used clockwise and (inhour) magnetic field rotation counterclockwise.Should be appreciated that the sense of rotation that changes driving magnetic field is the problem of the relative phase of the level of change drive signal and vertical component.For this structure, read operation turns clockwise magnetic field so that domain wall spreads into fan-out element 34 is used to read with use.When domain wall arrival is connected with the NOT door of data input element 36, it will be divided into two.A part will be propagated by output line and continue to pass through shift register.Another part will be propagated along the middle stump of NOT door with around (clockwise) corner before arriving data input element 36.Here, domain wall or eliminate at the stump place, obstructions that perhaps become simply because it can not be escaped to propagate into backward in the circuit, makes the data write element be used as the domain wall black hole.
For writing, use counterclockwise (inhour) magnetic field so that domain wall propagates into outside the data write element 36 and enters the NOT door that it is connected to.When data bit was written into, the vertical magnetic field amplitude was increased to and reaches the full field cycle on " writing threshold value ", assembles two domain walls.When first domain wall arrives NOT door knot, it will be divided along NOT door input and output line.The domain wall of propagating around counterclockwise corner continues to advance around shift register.Another domain wall has first corner that turns clockwise advancing to advance to before turning back to the NOT door.Thereby this domain wall runs into second then assembles the domain wall elimination.If do not produce second domain wall, first domain wall " returning " part will be vibrated in stump in the middle of the NOT door and use domain wall to fill shift register.
The more complex way of this scheme (5) show in Figure 12.This operates in the mode identical with the simple scheme that shows among Figure 11.These circuit can use with top selective erasing function with reference to figure 6 descriptions.
Therefore, the example of the alternative magnetic shift register configuration of using bi-directional drive magnetic field has been described now.This scheme can be used the electrical circuit system drive that is not directly connected to magnetic circuits, be write, reads and delete, and can form in every layer of multi-layer device that has more than a magnetic circuits element.
With reference to Figure 13, the example of 7 serial shift registers will be described now.Because data input element 36 is parts of shift register, this example apparatus is 5 equipment.A plurality of fan-out parts 37 allow each domain wall to be read out more than once, although the destructive data of this equipment is read.As shown, domain wall can be read simultaneously four positions.This provides the output of 4 multiplying factors to amplify effectively.Therefore can increase the signal to noise ratio (S/N ratio) that data are read.The scheme of this a plurality of fan-outs that data are read is not limited to use and go for any magnetic circuits in the destructive data sensing circuit.
Because the shift register of this example be open rather than the loop, it is mainly as delay circuit, is reading data delay 5 bit periods that part 37 places will write at write element 36 places before reading.
The example shift register that the input of Figure 14 video data connects via fan-out.Here, data input element 38 is free of attachment to the NOT door via the introducing of fan-out element.Show ' level ' data input element in this example, but suitable corner will allow to use ' vertically ' equivalent.This equipment uses clockwise and counterclockwise driving magnetic field direction.In readout mode, domain wall is propagated around the loop in the clockwise direction.The domain wall of incident will be divided into two on fan-out, a part continue around the loop and another part before the end of data input element 38 is eliminated along fan-out arm advance (to allow reading) by long-range magnetic field sensor.The pattern of writing will be used the rotation of counterclockwise magnetic field.The domain wall that arrives the fan-outs knot from data input element 38 should be divided and opposite direction advance (so fan-out knot in this pattern effectively as the NOT door) major loop initially.Domain wall continues around the loop and another will run into the corner of clockwise turning and turn back to the fan-out knot.Along with its is propagated by fan-out, a domain wall will continue in the loop, produce second of two domain walls of the equipment that is input to, and another will be advanced along data input element arm.For ' level ' element, this domain wall will be eliminated.For ' vertically ' element, thereby the assembly of second domain wall will be the necessary vibration condition of avoiding as described in reference Figure 11.
This scheme provides the advantage of density of equipment aspect, because inside, NOT door loop does not have the occupied input element that holds according to this in space.Though input element self occupies relatively little area, any increase of the width in master shift register loop is to hold input element necessarily for the whole length in loop and continue.Use the interdigitation of relative NOT door, inner removal data input element can produce the twice coefficient difference of density of equipment from the shift register loop.
Therefore, described now the example of the alternatives of the magnetic circuits shift register that uses unidirectional and bi-directional drive magnetic field, can be driven all, write and read and do not need directly being electrically connected to magnetic circuits.In some instances, circuit also can be optionally from wherein deletion, and do not need directly being electrically connected to magnetic circuits.
Describe referring now to Figure 15 and 16 and can be used for making the more multicircuit element that is suitable for the magnetic circuits that in above-mentioned magnetic apparatus, uses and the example of structure.
Figure 15 A shows the magnetic logical circuit that comprises NOT door tip 71, fan-out knot 72 and intersect knot 73.Entire circuit is arranged in rotating magnetic field (being rotated counterclockwise in this example).The NOT door makes at least one domain wall will be present in the loop to allow to be easy to experiment test with the loop structure manufacturing.But in the circuit of this example, the domain wall that propagate in the loop in Figure 15 A necessarily also passes through decussate texture, as signal indication among Figure 15 B.In order before measuring, to obtain the clear initial state of single domain wall, using the low amplitude rotating magnetic field to eliminate adjacent domain wall to before, the equipment magnetization is at first saturated in big (＞200 Oe (15920A/m)) magnetic field.Because the synchronizing characteristics of logical device, circuit geometries will be defined as around the domain wall travel-time in NOT door/loop by 1/2 magnetic field cycle of NOT door and 1 magnetic field cycle of per 360 ° of loops.Therefore, single domain wall round trip spent for 5/2 magnetic field cycle, caused the magnetization change-over period in 5 magnetic field cycles.The fan-out element forms the part in this loop, but does not influence the domain wall round trip cycle.The output of fan-out feeds back in the loop, thereby and another extend to long-armed in to provide the sensing element can the monitoring loop magnetization.
Suitably be rotated counterclockwise in the magnetic field, from position among Figure 15 A " *" magneto-optic Kerr effect (MOKE) mgnetic observations indicate change-over period (Figure 15 C) in 5/2 magnetic field cycle, confirm that NOT door, fan-out and crossing member correctly work.Therefore the circuit of Figure 15 provides the simple cycle counter-rotating, alternately keeps logical one and " 0 " state, once reaches for 5/2 magnetic field cycle.
In four kinds of logic architecture elements (NOT, AND, fan-out and intersection), intersect that solid existing get up may tool challenge, because its operation can be to the nanowire size sensitivity of knot.
In order to cross crossing member 73, domain wall must expansion be crossed over knot, a kind of very expensive technology fully before can further propagating along output line.But, allow domain wall to propagate scarcely along the perpendicular line direction, otherwise the numerical information in will restructuring.On the contrary, the domain wall of propagating by the fan-out knot will broaden and expand gradually from incoming line along with knot, when the arrival output line time, be divided into two independent domain walls before.Form in this example of track at the magnet-wire that uses the 200nm width, intersection has following size.For the distance of any side 500nm that ties on whole four directions, track is narrow to the 183nm width.Track also perpendicular meets, so that guarantee that knot is as intersecting rather than fan-out.Can in WO02/41492, find about the more details that how can form the intersection knot.
Being integrated in the nanometer line network that shows among Figure 16 A of whole four kinds of logic elements finished, and comprises NOT door, AND door, two fan-out knots and an intersection knot.Previous work (people such as C.C.Faulkner, IEEE Trans.Magn.39,2860 (2003) and WO02/41492) show, the converts magnetic field of AND door output line depend on incoming line any one not, one of them still be two all comprise domain wall, converts magnetic field reduces along with the incident domain wall that increases number.Functional in order to realize logic AND, the AND door has DC field biasing H x DCThe elliptical rotating field in the operation.This is similar to previous pseudo-AND operation and how has realized (R.P.Cowbum, M.E.Welland, people such as science 287,1466 (2000) and D.A.Allwood, Appl.Phys.Lett.81,4005 (2002)) in other individual layer magnetic systems.The remainder of magnetic circuits is designed to sequentially provide whole four kinds of two input equipments may the logic input make up to the AND door among Figure 16 A.But all toe-ins must be able to be tolerated the biasing of DC field, because this is applied globally.
NOT door 81 in the backfeed loop is as the signal generator (providing alternating logic " 1 " and " 0 " signal via fan-out 82) of network remainder.This NOT door 81 had for 3 change-over periods in magnetic field cycle, because need three cycles to propagate domain wall around the loop.Therefore it is outside and to the second fan-out element 83 in succession, domain wall is divided into two paths once more there that this backfeed loop supplies to domain wall the loop.The MOKE of position I measures the change-over period (Figure 16 B, trace I) in 3 magnetic field cycles of indication among Figure 16 A, and confirmation NOT door 81 and fan-out element 82,83 are in succession correctly worked.Between position I and II (Figure 16 A), domain wall will postpone for 1/2 magnetic field cycle, because this is to propagate domain wall by the required holocyclic amount (referring to Figure 16 B, trace II) of this circuit part.But in order to make the domain wall in-position III from second fan-out knot, they must be through tying the 84 other loops that form by comprising to intersect, and this provides the propagation delay in a magnetic field cycle in this domain wall path.Therefore, II compares with the position, and the magnetization of position III will postpone 1 magnetic field cycle (Figure 16 B, trace III).The direction of magnetization at position II and III place is determined the logic input state of AND door 85.Only the qualification of the logic of AND door is that it has output valve ' 1 ' when two inputs all are ' 1 ', and has output ' 0 ' for every other situation.The measurement of the position IV of magnetic circuits (Figure 16 B, trace IV) shows that this is (the using high MOKE signal to refer to the agreement of logic ' 1 ') of setting up here, illustrates that the AND door correctly operates with other three kinds of component types.
Therefore, described the example circuit of making by circuit component now, can operate the magnetic circuits of carrying out the complex logic function in various combination thereby it can make up to form.With reference to figure 3, thereby the 4 and 5 data write elements of describing can allow valid data to be input in the logical circuit with any use of these more complicated logic functions.Therefore, can use the magnetic circuits in the multi-layer device to carry out complicated logic function, wherein use not have to drive, write and read magnetic circuits to the electrical circuit that directly is electrically connected of magnetic circuits.
According to very common thermodynamics basis, the energy that consumes in each domain wall logic element is necessarily less than each output conversion 2M sH aV, wherein M sBe that (for permalloy is 800emu cm for the saturated magnetization of magnetic material -3, 1emu=10 wherein -3Am 2), H aBe that the amplitude of externally-applied magnetic field and V are the volumes of the magnetic material changed in door and its output nano wire.For the experimental facilities of describing in this paper, the representative value of the energy of each operation is 10 -5PJ (2000k under the room temperature BT, wherein K BBe that Boltzmann constant and T are temperature), with each typical energy 10 for the CMOS of 200nm minimum feature size -2PJ compares.This can allow big 3 dimension domain wall logical circuits operations and can be not overheated.Should be noted that not necessarily Low-power Technology of domain wall logic, because when producing magnetic field, may have sizable inefficiencies.Use small size (hundreds of μ m by strip line being used for the local magnetic field generation 2) domain wall CMOS promiscuous device, absolute power consumption can keep low.But, may finally solve these inefficiencies fully by the domain wall propagation of spin transfer.
The following zoom capability of domain wall logic depends on the interaction between thermodynamic stability and the required externally-applied magnetic field amplitude.These two all depend on F, form the width of the nano wire of logic element.If the width of nano wire and thickness is convergent-divergent together, then shape anisotropy remains unchanged.For at first ordering, therefore the intensity of the externally-applied magnetic field that the manufacturing edge roughness of solution logic element and uncontinuity are required keep constant.In this case, the energy of each conversion and the volume of magnetic material are proportional, with F 3Proportional.Therefore, when F=70nm, the magnetic logical device that 1.8nm is thick should consume 3 * 10 -7PJ (70kBT under the room temperature), this is the lower limit of thermodynamic stability.For further reducing of F, device thickness should by with F -1/2Proportional and increase so that keep the constant in energy of each conversion.This will cause that shape anisotropy increases, thereby domain wall is propagated by required externally-applied magnetic field of line and the structure uncontinuity that is associated with toe-in.The same with MRAM, the final restriction of convergent-divergent will be when required externally-applied magnetic field becomes big unrealisticly.
The special characteristic of some of top example is 2 dimensional planes that are not limited to when placing circuit.The same unlike CD, tape with the magnetic hard-disk storer, do not need the machinery or the access of circuit surface.And, unlike electronic circuit, do not need the electrical access of circuit surface.Substrate may be positioned to push up each other to be gone up to form 3 dimension logical organizations.This has the advantage that allows to realize higher current densities.Under the situation of data storage circuitry, realize that therefore the very high density of data storage is possible.If desired, all substrates can be shared identical applying rotating magnetic field in the structure, thereby keep layer synchronized with each other and reduce the complexity of equipment.Circuit can be configured to the single serial data stream of I/O, perhaps if desired, can store the data word stream of multidigit width by using several rings or layer concurrently.
Memory device based on magnetic shift register can be used for widely applying as mentioned above.Should be appreciated that for the access time that is stored in the data in this equipment depend on each shift register size (bit address stand-by period just) and the rotation driving magnetic field clock speed.The storer of different access times can be suitable for different purposes.For example, the storer of low access time can be carried out the function relevant with hard disk drive usually, thereby eliminates the Mechanical Reliability problem of interior mass data of computing machine and procedure stores.
The storer of higher access time can be used for for example interim storage of the digital music of MP3 player of for example pocket digital audio-frequency player (this application need usually continuously the numerical information of playback low cost, non-volatile, can rewrite storage), the interim storage of digital photos in the digital camera (this function is current to be realized by flash electronic memory expensive and that have a finite population rewrite cycle), the non-volatile offline storage of mobile phone, individual affair management, palmtop computer and SMART card.
An attractive feature of the domain wall logic of using in foregoing circuit and equipment is its very big simplicity.Logic NAND uses three transistors to realize in CMOS, yet the domain wall logic is used two elements (NOT and AND).Usually need six transistorized logic AND functions of CMOS to realize by two magnetic nanometers are put together simply.The fact is that unlike silicon CMOS architecture, domain wall intersection knot can be realized in single plane and not need multistage method for metallising, can produce the equipment of very low cost in principle.Though the great majority of magnetic logic are used (the in fact more wide-range of spintronics) and be will be referred to comprise that the SOC (system on a chip) that mixes based on the CMOS of silicon, some application examples such as biomedicine are implanted maybe can wear the ability that computing hardware will be benefited from manufacturing equipment on flexible polymer substrate for example.Can imagine the nano wire that is configured to 3 dimension neural networks or extremely intensive 3 dimension nonvolatile memories.All provide the ability of power supply, clock, master reset and serial input attractive especially under 3 limited dimension situations of signal access as shown in Figure 4 via single externally-applied magnetic field.Also may have the possibility of the emerging dilution ferromagnetic semiconductor of domain wall logical and interface, this allows magnetized electrical control and sensing.
Though described in detail above-mentioned embodiment, in case the disclosure above understanding fully, many variations and modification will become obvious to those skilled in the art.Following claim plan is interpreted as comprising all this variations and modification and their equivalent.

Claims (44)

1. magnetic logical device comprises:
First substrate that is used for the general plane of electrical circuit;
On first substrate, form, be used for second substrate of a plurality of general plane of magnetic circuits with stacked arrangement;
Each described second substrate has magnetic circuits formed thereon;
Each magnetic circuits has a plurality of logic elements, data write element and data sensing element;
Wherein the data write element of each magnetic circuits aspect plane positioning corresponding to each magnetoelectricity write element of first substrate; And
Wherein the data sensing element of each magnetic circuits aspect plane positioning corresponding to each magnetoelectricity sensing element of first substrate.
2. according to the magnetic logical device of claim 1, wherein logitron comprises at least one data storage elements.
3. according to the magnetic logical device of claim 1 or 2, wherein each second substrate is separated by non-ferromagnetic layer.
4. according to the magnetic logical device of claim 3, wherein non-ferromagnetic layer comprises the material that is selected from dielectric substance, polymeric material and non-ferromagnetic metal material.
5. according to the magnetic logical device of any one front claim, wherein each described second substrate has a plurality of magnetic circuits formed thereon.
6. according to the magnetic logical device of any one front claim, wherein magnetic circuits is formed by the nano wire of magnetic material.
7. according to the magnetic logical device of claim 5, wherein each logic element is by being connected to form between the nano wire.
8. according to the magnetic logical device of any one front claim, wherein data write element and data sensing element are the physics discrete components.
9. according to the magnetic logical device of any one front claim, also comprise the magnetic field generator that produces the rotating magnetic field that is used to drive magnetic circuits.
10. according to the magnetic logical device of claim 9, wherein magnetic field generator can be operated to produce magnetic field clockwise and/or counterclockwise.
11. according to the magnetic logical device of any one front claim, wherein the data write element comprises the amplification stump of logic NOT door.
12. according to the magnetic logical device of any one front claim, wherein the data write element comprises that coercivity is lower than the circuit part of adjacent circuit part.
13., wherein form the circuit part that coercivity is lower than adjacent circuit part and have the geometric configuration different with the adjacent circuit part according to the magnetic logical device of claim 12.
14. according to the magnetic logical device of any one front claim, wherein magnetic circuits also comprises and wipes part.
15., wherein wipe part each electric part of wiping aspect plane positioning corresponding to first substrate according to the magnetic logical device of claim 14.
16. according to the magnetic logical device of any one front claim, the writing part and read part the writing part and read part skew of magnetic circuits from second second substrate of magnetic circuits in first second substrate wherein.
17. according to the magnetic logical device of any one front claim, wherein the magnetic of magnetic circuits depends on the physical geometry of circuit.
18. one kind comprises the data storage device according to the magnetic logical device of any one front claim.
19. a magnetic circuits equipment comprises:
The substrate of a plurality of general plane that form with stacked arrangement, each described substrate has magnetic circuits formed thereon;
Each magnetic circuits has a plurality of logic elements, data write element and data sensing element;
Wherein the data write element of each magnetic circuits aspect plane positioning corresponding to the desired location of each magnetoelectricity write element; And
Wherein the data sensing element of each magnetic circuits aspect plane positioning corresponding to the desired location of each magnetoelectricity sensing element.
20. according to the magnetic circuits equipment of claim 19, wherein each second substrate is separated by non-ferromagnetic layer.
21. according to the magnetic circuits equipment of claim 20, wherein non-ferromagnetic layer comprises the material that is selected from dielectric substance, polymeric material and non-ferromagnetic metal material.
22. according to any one magnetic circuits equipment of claim 19-21, wherein each described second substrate has a plurality of magnetic circuits formed thereon.
23. according to any one magnetic circuits equipment of claim 19-22, wherein magnetic circuits is formed by the nano wire of magnetic material.
24. according to any one magnetic circuits equipment of claim 19-23, wherein data write element and data sensing element are the physics discrete components.
25. according to any one magnetic circuits equipment of claim 19-24, wherein each magnetic circuits can be operated to be driven by rotating magnetic field.
26. according to any one magnetic circuits equipment of claim 19-25, wherein the data write element comprises the amplification stump of logic NOT door.
27. according to any one magnetic circuits equipment of claim 19-26, wherein the data write element comprises that coercivity is lower than the circuit part of adjacent circuit part.
28., wherein form the circuit part that coercivity is lower than adjacent circuit part and have the geometric configuration different with the adjacent circuit part according to the magnetic circuits equipment of claim 27.
29. according to any one magnetic circuits equipment of claim 19-28, wherein magnetic circuits also comprises and wipes part.
30., wherein wipe part desired location corresponding to each magnetoelectricity erased element aspect plane positioning according to the magnetic circuits equipment of claim 29.
31. according to any one magnetic circuits equipment of claim 19-30, the writing part and read part the writing part and read part skew of magnetic circuits from second substrate of magnetic circuits in first substrate wherein.
32. according to any one magnetic circuits equipment of claim 19-31, wherein the magnetic of magnetic circuits depends on the physical geometry of circuit.
33. one kind comprises the data storage device according to the magnetic circuits equipment of any one claim 19-32.
34. a method of making the magnetic logical device, this method comprises:
Form electrical circuit on first substrate, electrical circuit comprises a plurality of magnetoelectricity write elements and sensing element;
Form second substrate of a plurality of general plane on first substrate with stacked arrangement, each described second substrate has magnetic circuits formed thereon;
Wherein each magnetic circuits comprises a plurality of logic elements, data write element and data sensing element; And
Wherein the data write element of each magnetic circuits aspect plane positioning corresponding to each magnetoelectricity write element of first substrate; And
Wherein the data sensing element of each magnetic circuits aspect plane positioning corresponding to each magnetoelectricity sensing element of first substrate.
35. a method of making the magnetic logical device, this method comprises:
Form first environment division that comprises electrical circuit on first substrate, electrical circuit comprises a plurality of magnetoelectricity write elements and sensing element;
On the 3rd substrate, form second environment division of second substrate of a plurality of general plane that comprise stacked arrangement, each described second substrate has magnetic circuits formed thereon, magnetic circuits comprises a plurality of logic elements, data write element and data sensing element; And
Connect first and second environment divisions, make second substrate be arranged between the first and the 3rd substrate, and make the data write element of each magnetic circuits aspect plane positioning corresponding to each magnetoelectricity write element of first substrate, and the data sensing element of each magnetic circuits aspect plane positioning corresponding to each magnetoelectricity sensing element of first substrate.
36. a method of making memory device comprises according to claim 24 or 35 and makes the magnetic logical device and the magnetic logical device is merged in the memory device.
37. one kind writes the method for magnetic circuits with data, this method comprises:
In rotating magnetic field, locate magnetic circuits; And
At least the rotating magnetic field in the data write element position of modulation magnetic circuits.
38. according to the method for claim 37, wherein the data write element comprises that coercivity is lower than the circuit part of adjacent circuit part.
39. according to the method for claim 37 or 38, wherein magnetic circuits is not electrically connected the modulation source of showing up.
40. one kind basically as mentioned with reference to the magnetic logical device of any one description of figure 3-16.
41. one kind basically as mentioned with reference to the magnetic circuits of any one description of figure 3-16.
42. one kind basically as mentioned with reference to the memory device of any one description of figure 3-16.
43. one kind basically as mentioned with reference to the method for the manufacturing magnetic logical device of any one description of figure 3-16.
44. one kind basically as mentioned with reference to the method that data is write magnetic circuits of any one description of figure 3-16.
CNA2006800353488A 2005-08-03 2006-07-19 Memory access Pending CN101273412A (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
GB0516003.1 2005-08-03
GB0516003A GB2430318B (en) 2005-08-03 2005-08-03 Memory access
US60/707,196 2005-08-03

Publications (1)

Publication Number Publication Date
CN101273412A true CN101273412A (en) 2008-09-24

Family

ID=34984048

Family Applications (1)

Application Number Title Priority Date Filing Date
CNA2006800353488A Pending CN101273412A (en) 2005-08-03 2006-07-19 Memory access

Country Status (2)

Country Link
CN (1) CN101273412A (en)
GB (1) GB2430318B (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103026417A (en) * 2010-07-09 2013-04-03 国际商业机器公司 Magnetic spin shift register memory

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2403080B (en) * 2000-11-17 2005-07-13 Eastgate Invest Ltd Data storage device

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103026417A (en) * 2010-07-09 2013-04-03 国际商业机器公司 Magnetic spin shift register memory
CN103026417B (en) * 2010-07-09 2016-02-03 国际商业机器公司 Magnetic spin shift register memory

Also Published As

Publication number Publication date
GB2430318A (en) 2007-03-21
GB2430318B (en) 2007-08-22
GB2430318A8 (en) 2007-03-23
GB0516003D0 (en) 2005-09-07

Similar Documents

Publication Publication Date Title
US7554835B2 (en) Memory access
JP5634422B2 (en) High-speed and low-power magnetic devices based on current-induced spin moment transfer
US20100128510A1 (en) Magnetic Data Storage
US8879307B2 (en) Magnetoresistive device and nonvolatile memory with the same
US7502244B2 (en) Data storage device
CN111768806A (en) Magnetic skynet based memory device and method for storing information by using same
EP2649620A1 (en) Magnectic structure
CN101273412A (en) Memory access
Parkin Racetrack Memory: a high capacity, high performance, non-volatile spintronic memory
KR100912436B1 (en) Data storage device
JP4463564B2 (en) Data storage
Cockburn Tutorial on magnetic tunnel junction magnetoresistive random-access memory
JP2006504210A5 (en)
GB2436490A (en) Multiple layer magnetic logic memory device
Lenssen et al. Expectations of MRAM in comparison with other non-volatile memory technologies
Cockburn The emergence of high-density semiconductor-compatible spintronic memory
Katti et al. GMRAM: giant magneto-resistance random-access memory
JP6555256B2 (en) Magnetic element, initialization method thereof, and semiconductor integrated circuit
Roxy Reading and Programming Spintronic Devices for Biomimetic Applications and Fault-tolerant Memory Design
Goldfarb et al. AS CONTEXT for this book, computer memory hierarchy ranges from cache (fastest and most expensive) to main memory, to mass storage (slowest and least expensive). Cache memory, immediately accessible by the central processing unit, is usually static random-access memory (SRAM). Main memory is usually dynamic random-access memory (DRAM); like SRAM, it requires power to maintain its
Shi Magnetic switching in high-density MRAM
Cowbum Digital logic using magnetic nanostructures
Tian High Density Three-Dimensional Nanomagnetic Logic Systems Composed of Material with Crystalline Anisotropy
Prince Magnetic RAMs
Vijayaraghavan An analysis of MRAM based memory technologies

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
AD01 Patent right deemed abandoned

Effective date of abandoning: 20080924

C20 Patent right or utility model deemed to be abandoned or is abandoned