DE1424515A1 - Magnetic storage of thin layers - Google Patents

Description

DIPL-ING. HANS BEGRICH - DIPL-ING. ALFQNS WASMEIER

REGENSBURG 3 - LESSINGSTRASSE IQ 1 A? Δ 5 1 Patent attorney »Beschich-Waimeler, 8400 Regensburg 3, Pastfach

To the

German Patent Office

8 Munich 2 Zweibrüekenstr. 12th

TJ _- / ~ £ _ψ JQ XT) I B

* P

ifon 0941/31055 ■. State Bank, Regensburg 507 Check account: Munich 89369

Telegrams; Begpatent Regensburg Your sign Your message from

Please state our reference in the answer

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lay

March 2, 1964 W / E

I 22 477 IXc / 42m

International Computers and Tabulators Irbd.

"Magnetic storage of thin layers"

The invention "relates to magnetic memories with thin ferromagnetic layers and in particular on magnetic memory with a matrix of magnetic memory elements, a Variety of magnetic drive elements that make up the storage elements selectively drive; and a plurality of conductors that support the drive elements couple inductively with the storage elements.

Various types of memory matrices with thin magnetic layers are already known. In memories having multi-level, each level of an aluminum plate which iirägt- a coating of a thin magnetic layer and a matrix of fuel and query conductors "word blowing head build a field in a small angle to the heavy magnet of the thin layer isierungsriehtung and digits blowing head a field at a small angle to the easy direction of magnetization. Be query

880/089?

Patent attorneys Dipl.-Ing. Hans Gründlch - German-lng. Alfons Wasmeler - Regensburg, LesslngstraQ »10 Biau g ^ iw8dir.aeavom2.3.64 W / E ^ani I 22 477 IXo / 42m ICT I / p

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Ladders are parallel to the digit ladder. The number writers are common to all levels of a memory, while the word divider is assigned to each level individually are. A word is written into memory by that the corresponding digit writers together with the Word dribblers are excited at the desired point in the word.

Such a memory of thin layers shows a problem * that occurs in all memory systems geared towards words, namely the selective control of the one desired " Word dribble from the many existing ladders in one big memory. Where a memory from a matrix of Magnetic storage cores exists, has already been prescjaierg & n, to provide a matrix of drive cores that performs this selective control process. In this way becomes a definite Drive core selected and using a two-coordinate system switched by conductors that are inductively kogelt with the drive cores are. Each word divider of the memory is inductive with coupled to another drive core. A magnetic field is generated by a word conductor when the corresponding drive core is switched will. This magnetic field in conjunction with fields that generated by the excitation of selected digit letterheads causes a desired word to be written into the memory will.

A. such a matrix of driver cores can be selected for controlling Elements of a magnetic memory thin film used However, this arrangement would have the following disadvantages. First the switching of the magnetic core takes place in comparison to that with thin magnetic layers slowly; the use of cores would therefore limit the operating speed of the memory;

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Patent attorneys Dipl.-Ing. Han * Begldi - Dipl.-Ing. Alfont Watmeier - Regensburg, Lessingstrasse 10

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keep it relatively low. Second, a thin layer storage layer can be made entirely by vacuum evaporation or the conductors can be applied to the thin layer in the form of printed circuits will. On the other hand, a core matrix requires a completely different manufacturing process, with wires running through the Cores need to be threaded. e can be used to drive a thin film memory these wires have to be soldered to the conductors, for example of the memory. If a large string is to be created, the core matrix and the connection of this matrix to the memory / Obviously very difficult and time-consuming. If the feeder with a to work at a high operating speed, the Driving cores with the Speieherlementen connecting conductors very be short so that the inductance of the conductors is kept as small as possible. This means that the driving cores must all be very close to the thin layer of the storage tank, and the production and the connection of the drive core matrix is consequently even more difficult and expensive.

The use of a / diode array to drive a memory thinner layer would allow a higher operating speed of the memory, such a diode matrix would, however can be very expensive and complex to manufacture. Furthermore, there arises the difficulty of connecting a core drive matrix with a memory thin layer also in the case of a diode friction matrix,

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• S 3.5.1966 "« / He. J 22 477 IXc / 42m · ~ "

It is the aim of the present invention to provide switching elements, which are the selected areas of thin-film magnetic storage media drive, which even surfaces of anisotropic, ferromagnetic, thinner films are and therefore both in terms of speed as well as the construction with / the memory areas can work together. In this context it was established that that the operating speed of the driving elements is also increased by placing these elements between two states are switched, in which the magnetization vector in a from two opposite directions along the heavy axis is aligned instead of the usual easy axis alignment of the vector. This method of switching these elements also results in an increase in the available memory switching current, which of a given thickness of the film for the elements themselves are generated.

According to the invention, a switching element for driving an anisotropic, thin, ferromagnetic film memory characterized in that there is a further, well-known surface anisotropic, ferroroagnetic films with perpendicular to each other standing light and heavy magnetization axes that a magnetic bias field of the surface, e.g. by applying of an electric current is applied to a conductor which is normally coupled to the surface in order to generate the magnetization f vector to keep the surface aligned with the heavy axis in one direction and that the magnetization vector in alignment with the heavy axis switched in the opposite direction, giving the area a sufficiently large magnetic Switching field is abandoned so that the influence of the preload field is overcome, e.g. by supplying electrical current to the Surface coupled switching conductor is applied.

909850/0997

3.3.1966 W / He ■ J 22 477 IXc / 42m

Preferably, the conductor generating the biasing field is common to a number of switching elements, the conductors being arranged in matrix formation in two groups, with a different pair of conductors, namely one conductor from each group being coupled to each of the switching elements, and only the combined PeId, that is generated by currents flowing in each of the L _e iter coupled with the surface conductor pair, enough to get over the influence of the bias field in this area FU and to bring the face for shifting.

In the following the invention is based on an embodiment explained in more detail in connection with the drawing. The figure

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■ shows a schematic representation of a storage tank with --thin. Layers, . . .

In the drawing, two levels are shown, the part of a memory with thin layers made up of many Layers consists of an aluminum base 21, which has a thin ferromagnetic layer 22 for storing the information a thin ferromagnetic layer 23- £ um application of Control currents on the storage layer '2JkUfWe is en.

The various'! 'Parts of the arrangement shown in the drawings are not drawn to scale and the Figure shows the construction of a specific embodiment of an arrangement' according ä. Epfinetofcg sehematicich it again. For this reason, various parts of the arrangement are drawn in exaggerated size for the sake of better illustration, e.g. B. the relative thickness of the layers and the control conductors as well as the insulating layers, the relative dimensions of the various cables shown do not reflect the actual sizes of these parts.

The storage layer 22 is arranged so that it contains a matrix of storage areas by means of the conductors 2 * 4, 25, 26 which are arranged along two axes running at right angles to one another. The current conductors 25 and 26 are arranged in one direction and each conductor 's 5 is net angeord over a conductor 26. The conductors 25 work as / Jiffersteuerleiter and the conductors 26 are interrogators. Both groups of conductors are received by a carrier which has a basic insulating covering 13 and an intermediate insulating covering 14. The word control conductors 24 are perpendicular to the conductors 25 vjclq. 2t classified and are supported by a further IsolierbelaiX 15. The essay mentioned at the beginning describes the structure of the insulating coverings, the control ladder fvl: reii arranged in this ¥ eise, also a method for actuating the i / peicherbereicae of the ÜCiii 22. ^ ^:

This forms the part of the layer 22 which is below the central point a ladder 24 and a ladder 25 are included '«90 9850/0997 BAD

is chained to the ladders, an individual dining area for storing a single binary digit, with all digit storage areas a complete port along the word conductor 24- are arranged ..

In the Pigur there are only a few conductors for the sake of simplicity Representation shown - t, in practice the number is used Head so large, however, that a thousand or nioiir storage elements to be provided on "each storage slot *

The ErMger for conductors 25 and 2 <. is uia the inäe bent over two plates 21 and led back on the opposite side of the second level, as shown in the drawing, love of the two levels shown, additional levels can be provided, with the conductors 25, 26 and their support through the planes arranged in parallel ye-ye e +) can be carried out in the manner of a ye-ye e +), so that the conductors are linked * with storage film areas on each of the planes.

Each word conductor 24 is electrically connected at one end 27 to an aluminum support and runs transversely to the two layers 22 and 23 j; the other end 28 of the conductor is also electrically connected to the aluminum support. Each "forward conductor" together with the base thus forms a closed loop of low inductance which is coupled to a strip of each layer 22 and 25. The loop has a low inductance because the word conductor is only a short distance from the conductive base ΖΛ is arranged.

Every change in the flow in a rope of layer 23, which is connected to a word conductor 24-, i._duces an electric motor I see force in this conductor. This EMi ¹ .. generates a loop astrom that is a. magnetic! field on the strip of the film 22 is formed, the DFTC is coupled to the particular hoarder. In the form of the structure already described, the resistance of the loop and the portion of the flux that is not coupled to the layer can be neglected.

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without a noticeable error occurring. Hit those assumptions and taking into account the fact that the shift has a limited magnetic saturation value . the maximum value of the loop enatroiaes I is about:

where Lp and L * 'are the lengths of layers 22 and 23 coupled to the word conductor, Dp u ^ -cL E ~ ^ ^ie thicknesses of layers 22 and 23, W is the width of word line conductor 24, and H ₁ ~ the effective Designate the anisotropy field of the layer 23. <

_{The current I D} necessary to generate the required flow change in the layer 23 results from:

where Hjj 2 & ^{as is the} anisotropy field of the layer 22.

The thickness Dr, & ^eT storage well and the value of the loop current I are determined by the requirements for optimal operation of the storage system. It is useful to make L ₂ and L, about the same size. In this case, D can be made twice as large as Dg so that it is ensured that the loop current is greater than the minimum value required to control the storage layer. In a special .h. exemplary embodiment, the layers. 22 and 23 thicknesses of 1,000 Å, 2,000 pages and the word lemt ^ a width of 1 mm. A current I ^ of 3 amps would then result in a loop current on the order of 2 amps. If the current pulse I ^ has a short rise time, the loop current rises at approximately the same rate and then falls exponentially.

It was assumed above that the control layer 23 is driven in this way will that the Hagne-fcisierun ^ svektor differ from the easy ;;, direction of magnetization to the heaviness.; ·! K ^ .gnetization direction turns. The cross-sectional area of the layer that is used to generate

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3.

A certain loop current is required, is, is halved when the layer L! 3 from saturation with the alignment vector in the direction of the heavy axis into saturation is steered in the opposite direction.

From the above description it can be seen that it is possible that the To use control layer 23 to achieve the word control current for memory layer 22, the strips of layer 22, which is doubled with a word conductor, forms one Control area for the memory areas of layer 22, which are coupled with identical word conductors. So that works Layer 23 as the control for the storage element that by the. Layer 22 is formed. However, it is still necessary to make a selection of the particular word conductor 24 that is desired will make. This is done with the help of a half-current selection and to achieve a maximum output by switching the layer 23 from the orientation in one direction and the other in the difficult one ^ chse to achieve, become the erroderate tax manager about iir. Eh the easy axis of the ociiicht 23 aligned. In somewhat similar to how the peiciating element conductors become the öteuerelemeiit-steierladder carried by insulating coverings. The first! Irägerbelp.g 16 contains a group of word selection control conductors 31 * £ for each C-.th word control area of layer 23 one Ladder. As in the case of the beams 13 and 14, the beam becomes preferably vserpehtinen-shaped around the planes, namely in the L "rh.e of the control layer 23 of each level, so that the Conductor 51 with the corresponding word control film areas of each Jbene ·· '. chained iüt. Second and third insulating support coverings 17 and 18 the: ii] ra> er 16 are correspondingly superimposed .., the covering 17 ni: .-: nt a prestressing control ladder 29 that has ropes., those above ladders 24 and 31 in the word control areas of " Layer 23 lie. The conductor 29 is also provided with interconnection pass away, so that the above ; rende; i! 'rush connected in series over a single level. The conductors 29 of each subsequent level are shaded with the help of strips 19 in Heihe. The third carrier covering 8 takes an electric selection conductor 30, which is designed similarly to the conductor 29.

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• The intermediate lengths of the control currents that the control conductors 29, 30 and 31 will be considered in the following in detail, since they are the word control maturity of the layer 23 influence, each word being out of the range of layer 23, which lies under the control conductors and is concatenated with. these * The prestressing conductor 29 is with all Strips of the layer 23 coupled, which in turn are coupled to the word conductors 24 again. Am Voropannstrom from one Speisecra- elle 32 becomes kon tinnier Ii cii by d ^ n head 29 ' led »The resulting Vorspannfelä, which by deu Yorspämileiter generated vird * is enough to do. the stripes of the Layers 23 in a heavier direction below the Sfittigüngsweft to keep.

All strips of the layers 23 are also provided with a so-called X selection conductor (conductor 30) and a Y selection conductor (conductor 31) coupled. Each X_conductor 30 is connected to a power source 33 connected to select the plane and coupled to all strips of layer 23 of a single plane.

The supply source 33. v / e is separate output connections for ;. Each ₁ -de level, on and is s, o developed, that it has a current outlet ^ on only fB§. a level results in j. in which a Viort area is * -_. - should be chosen. Selection devices for such Zwe.pk.e -..-.- are known in the art. Each Y-conductor is, "a further StroHiq.Lielle 3 ^ _v ... connected to the 1st ^r orta, UPS ^ ahl. .Di ^ e., Food q.tieile has outputs for every position of one, .. ip> e-. ne and the same word positions in all levels are connected by the .: '.- .. Stromleiter Jffi utiil Jügul V) in Heine. The supply source 3% is designed in a similar way as a dBr supply source 33, and so, _s . that they are only. the desired location _> in, all. Levels of electricity supplies. . . . . . ..-, .....,., ·

In order to control a particular 'wordstroke' in a certain layer ..., 23, the X-conductor, dex *** ii8ebene, is coupled, _. excitement and; simultaneity, tivS, y. ^r is also excited. the Y-lead, which is connected with the corresponding word stripes "fc. The exciters

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The currents of the X and Y conductors are selected in such a way that the pressure generated by an excited conductor is sufficient to partially overcome the pre-spam field, so that a strip which, under the action of the pre-voltage field, creates a hollow conductor field , is brought into a state in which ⁷ T is just saturated in the one more blessed axis. In a strip of a layer that lies on the tension field and two ejector conductors, is controlled in the opposite heavy gauge to the state of saturation When each combination of an X-conductor and a Y-conductor is excited, a different strip of the films 23 is returned to the opposite saturation state and, as a result, a torque current is applied to a corresponding location of the storage elements of one of the layers 22.

As already stated, a courtesy to the operation of the memory areas is discussed in the above article. In this mode of operation, the selection results in a 3 pilot control strip, dr.f; a control current is induced in the assigned forward control conductor 24 and this generates a local control field, dr-s iJt the iiusgev, "lilten" / local control areas linked a üiffernfeld vird supplied to the einaelnen storage areas or not, depending on whether the Ciffernleiter .t5 erre; t were ■: ■ he niciit Jährend a ^ bIeeevorgangee v.ird only aas * ^r ortfeld zUiTeflüirt and Ausgan · is made... received the Abfrai'eleitem 26. Jn.mit are aie Lifiernleiter-25 ait -iueHF. Ziffemsteuerstron ^ enerat'or 35 and the ^ b- "'questionelGxter 2j with Aub; & ii _t * sver; V'r.: eri. , 6 v

The jvriiuüui ^ '"" - vii'de biox.er in Verbii.dim; hit the Vei "'.. ^; ~ fciKrjui-. d'uiiier Schic-τ eis. ι Ie -i.usw.j1i1- viii oxeverelemeiite for a certain X ¹ OrL". O:. o-ieiciierii described with thin schicäteii, iviiiiliche Jaipi'äi-uc-i '·:. aind jeloc; aaclj. i..with other - ^ types of bpeicr.er: i düimer kept nüjlich tmd it köiUi.e: i other SteuerGUsw'υ-: iora - ""in;; en for üie kept 2y ve ^. 'ei .üet 'v / ei ⁴ -aer .. \ ienii z. ~. Lweirichtuiv'cs-Zifi'ti-nsteuerfelaer for Xese. and öchrei "" A- ^ T- "ai: e in the individual lJ ^ eicherbereicnen' Yeri-feii-

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det v / ground, it can be useful to ensure that the three-way direction of the Haguetisierungsvelrtor of the control areas is given and constant for all! forte. In this case, as described in the above-mentioned article, the slight xi.chse of the layer 25 compared to the .u-chse. the after-school care center leader 24 can be tilted. Further die.Leiter 29 and 20 so arranged Seih that the over (Leu v'iortsteuerbereicnen the ^T Ji ilme 23 parts lying in parallel rather than in series, as shown in the drawing. In the latter case, it is expedient dia conductor 29 and 30 in such a way that the current flows in the same direction in all ropes of the corresponding current conductors reversed and current flows in the same direction in all conductors 51. This ensures that the polarities of the fields generated by conductors 29, «. 30 and? 1 remain in the same relationship to one another.

In the case in which the axis of the layer is tilted with respect to each conductor, the magnitude of the tilting movement is only a few degrees, so that the orientation of the magnetization vector of the control elements before and after switching still remains in the difficult direction. ,

The invention is not restricted to use for information storage devices with thin layers. A control element with stupid rails can expediently e.g. ß. to produce: un; of shift pulses can be used for a group of memory elements ...

Furthermore, a shift control element can also be used for controlling a other control element with thin bcLic.iten in the manufacture! - lunr of Io-iöoaen wchaltanordnuiif-eii be vervrejidet at which elements with aüni \ e :. Layers used v / era. "

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The distance between layers 22 and 23 is shown in the drawing to be much too large for better illustration, the distance; between the layers should be as small as possible, in order to keep the indu3.itivitut of the .ortclileife as small as n. -.lieh. It has "already been stated that the use of a conductive pad" helps to "" create a low inductance apart from rows and an appropriate path back for the conductors. However, a non-conductive pad can be used and the S. \! Cl-cv; eg for the word conductor is then formed by a conductor on the opposite ... side of the ociiiii.

The equation for the maximum loop current shows that it is a function of both the length of the control layer 23 coupled to the loop and the thickness of the control film. It is normally not desirable to make L much larger than Lp, as this would result in the de-act being spatially larger than the controlled activity. i> er '.ert of L-, can, smaller r-.as that of L "be ^{rushed by:.: 0} , α?.; ΐ the;) thickness of the layer 25 proportions! Encrypt / • jrü.-ert vircl, ^c -.ber it is not practically zv / eckmä.vig, _relative: i - o / e oonichtstürl: to use eii because the anisotropy with wachae: \ cier I> io..e rr.rölüer '..- ird and as a result the "dteuerströi.ie, - .. if.ο requireaerlicii ίάϋά, aiierwünscht gi * öii" will be.

l »ie ^ ej ehr ei'.van. ;; yü.sa memory, dvanier bein ducks according to the ii .. "·.: .. be-t, ueJ ü.F.ü üteueraysten in my training · - with 'each ¹ : ·. ¹ :; · ^ .. vorria. '^ uren., ■, \ ie c ..'. rnie ^ ciii hurries ei ·, use .., vereiia- ", '? i --- t. 'Jis Schicliteii 'λ'-j iier: ei through welder in the scm / eren .lic .tuiv- vcccc so rngejteuert, Ö ..-. 2 aie iaideruiig des ^ nst; aidea c j.ü.ell erf ol- ^ Gie x-olerai-izeij. with the ateuerströ-Men 'do not litter siüd. 3s it was also found that the minimum distance between Deii: -. Chbarteii control areas "of the film 23 is less -. In the minimum distance between word lines in memory" systh..i3xv. with thinner, ochichten. The structure of the control system is eilUIClJIlLIb v / e.jentiich simplified in comparison to x ϊι. '· Ι: ί b rti'i.'ithenieu or transistors "

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Claims (3)

1. Switching element for driving an anisotropic, thin, ferromagnetic film memory, characterized in that it has a further, per se known surface of an anisotropic, ferromagnetic film (23) with mutually perpendicular light and heavy magnetization axes, that a magnetic bias field of the surface, for example by applying an electric current to a conductor (29) which is normally coupled to the surface to keep the magnetization vector of the surface aligned with the heavy axis and that the magnetization vector in alignment with the heavy axis is switched in the opposite direction by applying a sufficiently large magnetic switching field to the surface so that the influence of the bias field is overcome, for example by applying electrical current to the switching conductors (30, 31) coupled to the surface. 2. Switching element according to claim 1, characterized in that the conductor (29) generating the biasing field has a number of switching elements What is common is that the switching conductors (30, 31) in matrix- training are arranged in two groups, with one different Pair of ladders, one from each group, with each one of the switching elements is coupled, and that only the combined field, that has been produced by currents flowing in each conductor of the with the surface coupled conductor pair flow, sufficient to overcome the influence of the prestressing field on this surface and the To bring the surface to switch. 3. Switching element according to claim 1, characterized in that a central storage element drive conductor (24) magnetically with a 90 98 5 0 / O ' 3.35.1966 W / He J 22 477 IXc / 42m Switching element and with a plurality of areas of a storage film (22) is coupled, and that an electrical signal that is generated in the Speieherelementtreibler in response to the switching of the switching element is induced, all storage areas of the Variety of land is abandoned. 909850/0997 BATH ORIGINAL Blank page