DE1519842A1 - Process for embedding or enclosing polycrystalline substances in single-crystalline material - Google Patents

Description

American Aviation, Ineο »El Segundo, California,

Process for embedding or enclosing polycrystalline substances in single-crystalline material "

The invention "relates to an ATo storage process for embedding or enclosing polycrystalline materials in single crystalline material ,,

Previous attempts to convert a polycrystalline material into single crystalline Embedding material or enclosing the polycrystalline material with the monocrystalline material, lead to a polycrystalline deposit on the surface of the encapsulated polycrystalline material «In effect, a polycrystalline material was encapsulated in a polycrystalline deposit Embedding or sealing in a single crystal not recognized «,

For example, as the name suggests, has the material of a single crystal has an uninterrupted crystalline structure and is constant throughout its structure Properties »The properties of a production

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walk to the other constant. The opposite result applies to polycrystalline production runs: “It is difficult to produce essentially identical properties in polycrystalline materials. On the other hand, the properties of single crystals can be better predicted and they are therefore easier to control.

Single crystals, which consist of magnetic substances, are anisotropic and can easily be seen in a given crystallographic Direction to be magnetized. Single crystalline materials can therefore be used as magnetic storage devices.

In a polycrystalline material, the direction of easy magnetizability is not the same for all crystals aligned and therefore the magnetization reasons are statistically distributed. Tn substances made from a single crystal consists, shows the direction of easy magnetizability in certain and known directions and is with respect to an electrically induced magnetic force rotated more predictably.

Ba the monocrystalline material in its entirety Its magnetic properties are more similar than poly-, crystalline material, is used to magnetize a selected Less force required in the area. The saturation of the single crystal material can be achieved more easily than with polycrystalline 'substances and therefore less electricity

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'■■■'. ■ ■ ■. ^-5::: ■■■■■■

needed. E.g. you can, if the material is used for it is going to make the core of a miniature choke coil, by encapsulating a polycrystalline conductor, "with the same amount of current a higher and similarly recoverable Inductance "obtained in a single crystal device compared to a polycrystalline device. .

It is also possible to embed a polycrystalline material in the structure of a single crystal or with it to enclose it and then to dissolve the encapsulated polycrystalline substance, resulting in holes, openings or Leaves channels in the single crystal. Such a structure can be useful in laser devices in which single crystals be used frequently. The holes or channels can be used to 'coolant' through the crystal to circulate to dissipate heat,

"Embedding or enclosing", in addition to the ordinary meaning of these words, includes "encapsulating" and "include" where, for example, a polycrystalline Substance is completely surrounded by a single crystal. the Terms also include cases where the polycrystalline Material is not completely surrounded.

Another use of the procedure is to [To form transistors with a metal base, which have layers of a semiconductor single crystal on each side.

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Other circuits and devices can also be fabricated by the egg bedding or encasing process will.

Accordingly, it is an object of the invention to embed polycrystalline substances in monocrystalline substances, or to enclose them in monocrystalline substances. .

It is another object of the invention to make improved magnetic devices by using a Process for embedding or enclosing polycrystalline substances in monocrystalline substances is used.

Another object of the invention is to provide methods of manufacturing a magnetic memory device ·

It is a process of embedding or enclosing polycrystalline material in a single crystal Material invented It has been shown that when a polycrystalline material and a single crystalline Underground material are housed in a chemical evaporation chamber at a short distance from each other, and if the crystal structure of the monocrystalline substrate material is similar to that of the deposited reaction product, the single crystal subsurface is the preferred deposition site It has also been shown that a critical reaction rate can be established in this way

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may have the entire deposit on the "preferred single crystal .Substrate material occurs, and therefore no polycrystalline deposition on the polycrystalline material permitted. Therefore, the critical reaction rate can be found empirically by observing the deposit in an environment. The speed of response can be changed by changing the flow rate of the gases of the reacting elements until a growth rate of the single crystal is reached which is the formation rate of Crystal nuclei predominate.

A critical reaction rate can be for each material that is deposited and for the subsurface to be determined. Each combination of the deposited material and the subsurface material is different critical reaction speed. That means that each Combination of deposited material and subsurface material has a growth rate at which the deposit single crystal instead of polycrystalline. Therefore, no material is deposited on a polycrystalline Material that may be present in the reaction chamber as this will require the formation of crystal nuclei would. Although the polycrystalline material on the way the crystal growth of the deposited material the crystal structure of the deposit is only influenced by the monocrystalline substrate,

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and the polycrystalline material is different from the single crystalline Deposition without polycrystalline deposition inclusions embedded or enclosed.

In one embodiment of this invention, a polycrystalline material and a monocrystalline background material housed in an evaporation chamber a short distance from each other «The crystal structure of the monocrystalline substrate material is similar to that of a reaction product to be deposited, so that the monocrystalline Subsurface a preferred storage location is ο one critical reaction rate is established and all deposition occurs on the preferred single crystal There is no polycrystalline deposit on the substrate or on the polycrystalline material.

In another embodiment, a monocrystalline material is first placed on a monocrystalline substrate deposited and then the polycrystalline material is deposited. After the deposition of polycrystalline Material at a predetermined location on the single crystal Material, the single crystal deposition continues until the polycrystalline material is as desired is embedded or enclosed.

In a particular application of the method, a magnetic storage device is made by that a monocrystalline ferrite body is produced which is magnetically anisotropic and easy in a given

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crystallographic direction can be magnetized. In one embodiment of the device produced ■ a number of electrical conductors are crossed and insulated embedded in the ferrite body and essentially surrounded by it, so that a magnetic alignment in the ferrite is obtained by passing an electric current through one or more of the conductors'.

In another embodiment of the invented process is manufactured storage device, after the electric wires have been placed on the single crystal ferrite surface and one in advance have chosen direction with respect to the ferrite crystal and are approximately isolated at the crossing points, additional single crystalline ferrite material deposited over it, to first find the crossing point in a single crystalline Encapsulate ferrite material. For example, the direction of the ladder can be a selected crystal direction be parallel or perpendicular, or form an angle with it.

A special feature of the method of the present Invention consists in the fact that the ferrite body is formed by reacting selected metal halides and water vapor around the ferrite material epitaxially deposited in a preselected crystallographic shape.

In the following description and examples

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the method is under the conditions of manufacturing a magnetic storage device by encapsulation polycrystalline conductor in a single crystalline ferrite material te schriet) en β The description and the examples have only the purpose of the embodiments of the broad-based invented method for embedding or enclosing polycrystalline substances in monocrystalline Substances and the description and examples describe neither the application nor the scope of the invention exhaustive,. As indicated above, the method have many uses and many different devices can be made by the method will.

Other objects and features of the invention will become apparent from the following description.

Fig. 1 is an illustration of an apparatus used to do so is used to embed or enclose polycrystalline material in monocrystalline material.

Figure 2 is a cross-sectional view of the apparatus of Figure 1 taken along line 2-2.

Figo 5 is a cross section of part of the magnetic Memory device that can be manufactured by the present invention.

Fig. 4 is a perspective view of a storage system using a magnetic storage device manufactured by the present invention.

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Pig. 5 is a cross-sectional view of the storage device; showing the insulation between the conductors.

Referring to Figure 1, the apparatus of the present invention a chamber 1, which "preferably has a T-shape and inlet means 2 for blowing gases into one end of chamber 1 and an outlet 18 at the other End of part 4 includes. The cross part 4 is of one Surround heating element to regulate the temperature in part 4-. Inside the chamber 1 a number are spatially separated from each other separately arranged melting pots 5 carried. Everyone

these spatially separated melting pots,

'/ are attached to the central support rod 6, but can be held in their central position by any other known means. On the outer surface of the Chamber T is a heating element 7 which is arranged so that it surrounds each melting pot 5. Each element 7 can be controlled by itself so that the area in which each melting pot is located is set in advance Temperature can be heated. In the cross part 4 there is a quartz holder 8, the sub-plots or crystals 10 carries o the crystals 10 are along the cross part 4 of Arranged at a point from where the chamber 1 in the cross part 4 enters in the direction of the outlet port so that each is exposed to a mixture of gases entering from inlets 2 and 3. Inlet 2 is connected to a source (not shown) of a dry mixture of He and Ar

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tied together. Inlet 3 is connected to a source (not shown) connected, in the helium, argon and oxygen through Water being passed through to produce a mixture of noble gases, oxygen and water vapor, i.e. He, Ar, Op and H ^ O.

Sub-plots 10, on which the ferrite crystal is deposited or grows, "consist of a material whose crystalline structure is similar to that of the material to be deposited -. For the purpose of describing the ferrite storage produced by the invention, MgO is selected as the sub-base material, although other sub-materials, such as MgAl ₂ O ,, Al ₂ O, and other substances ^{having the formula Me 1} MeVo, can also be used to make the memory. The terms Me ¹ and Me "are explained below.

It should be noted that the method is not limited to the use of any particular substrate or crystal orientation. It is not limited to the use of the spinel materials mentioned here. The method and materials used in the process are limited only by the crystalline orientation of the material deposited and the method used in the deposition. For example, _0, the material may be deposited by chemical vapor working method. If so, many different substances can be deposited. Then a sub-

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base material with a crystal orientation selected, which allows a single crystal to be deposited on it. The rate of deposition depends on the type of subsoil and the deposited material.

The underground 10 is prepared by optically high quality MgO (optical grade MgO) along a (100) cleavage plane is split or by the MgO along its other crystal faces in plates of the desired configuration is cut. The panels are evenly primed to obtain a panel that has a selected one Size and a selected crystallographic Level, and the panels are then chemically cleaned in an acid etching solution.

The subsurface st lic ke 10 are carried inside the cross part 4- by holders 8 and a ferrite layer can be deposited as detailed below ο

The source materials 11 for producing the ferrite deposit on the substrate 10 are accommodated in containers 5 and are heated by various heating elements 7 until they evaporate. The source materials housed in the containers 5 may be Me ¹ Z ₀ , Me ¹¹ X _n, or a mixture of both, and Me 'may be Li, Mg, Mn, Fe, Co, Ni, Cu, Zn or Cd; where Me '' can be Al, Cr, Mn, Fe 'or Tij and where X is a halogen (F, Cl, Br or J), provided that one of Me'

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or Me "is Fe and the subscript" a "is either 1, 2, 3 or 4, depending on the valence of the cation. Simultaneously with the heating of the material 11, the above-described Carrier gases admitted through inlets 2 and 5.

The following reaction takes place on the surface of the Subsurface 10 instead of a ferrite film on the subsurface crystals deposited from MgO.

Me ¹ X ₀ + 2Me "X _n + 3H ₉ O + 1/2 Q ₀ + noble gases ^ -

Me ^f (Me "+ Fe) ₂ O. + 6HX + noble gases

As used herein, the term "ferrite" refers to compositions consisting only of bis-iron oxide, or of an iron oxide in chemical combination with at least one other metal oxide to form a magnetic material. Therefore, the term Me '(Me' * + Fe) ₂ Q * ^ ¹⁰ generally refers to these ferrite materials without a necessary reference to a particular stoichiometric or empirical composition or two metal oxides in chemical association with iron oxide ο Therefore, the ferrites formed are preferably ferrites which are of commercial interest and have small coercive force, ie, MnFe ₉ O., MFe ₀ O ,,, MgFe ₂ Q ^, ZnFe ₂ Q ^, CuFe ₂ O ^ uHd compositions of these compounds. Other ferrite material may vary depending on the

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desired application. be used »

After the first ferrite layers have been deposited on the substrate, the substrate is removed and placed in a conventional vacuum storage chamber (not shown). In the chamber are one or more polycrystalline conductors having a first set of parallel conductors deposited in a preselected direction relative to the crystal structure of the ferrite to the Oberfläche'des substrate according to known methods that is, j by vacuum deposition or atomization _β Electrically conductive materials such as gold, silver, platinum or copper can be used, but gold is preferred because of its excellent electrical properties. These conductors are preferably aligned with respect to the crystal plane in order to provide magnetizations along different directions. (See Smith et al. Ferrite- John Wiley & Sons- 1959) «.

After the first row of conductors has been deposited is, samples of the insulating material are deposited in a selected mister, around portions of the first row of conductors to cover. Such insulating materials, such as MgO, AlgO-z and BaFp can be made by common deposit working methods be deposited. There, after will be one or more Conductors that form a second row of conductors in a vacuum deposited in a way that they are the first row

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crossing at a prepaid angle and yet by the previously deposited insulation materials from you insulated

After the rows of conductors have been deposited with the appropriate insulation at each crossing point, the underground preferably in the chamber, housed, and a second ferrite body is existing on top of this Ferrite layer and deposited around the conductor to at least to enclose the crossing points of the rows of conductors within the single-crystalline ferrite mass »Of course you can the entire conductor must be enclosed.

In some cases, instead of embedding or enclosing a number of conductor templates or rows, it can also be advantageous to enclose a single conductor row and then to deposit and enclose a second row. In this embodiment, single crystal ferrite would separate the rows of conductors, whereas in the previous embodiment, the rows of conductors ^; separated by an insulating material other than ferrite. ·

Figure 2 is a cross-sectional view of the chamber showing more clearly the location of the cross member 4 and the crystals within the chamber.

In Fig. 3 there is shown in cross section an encapsulated conductor made in accordance with the preferred method described above,

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As shown therein, layer 12a is the first Deposition layer of the ferrite on the substrate 13, The conductor 14 represents one of the conductors of a row, while the second conductor row is perpendicular to the conductor 14 runs and cannot be seen in this cross-section can. The ferrite material 12b completes the enclosure. A perspective bar position of the one shown in FIG The device shown is shown in Fig. 4, which shows the rows of conductors 14 and 1.6, arranged at an angle to one another, the enclosure of which is closed off by the ferrite 12b. Ferrite has been deposited on a substrate 13 and the conductors are insulated from one another by the insulation 17. Fig. 5 is a cross-sectional view of a healing the figure 4, which shows the insulation 17 between the rows of conductors 14 and 16,

The application of the invented method to making a ferrite epitaxial memory device is shown in FIG an embodiment with reference to the following Describe examples in more detail.

Example I.

The base material% Q is prepared by the crystal along a (100) cleavage plane in subsurface thicknesses which are approximately 6.45 cm (one inch square). After splitting, the subsoil becomes mechanically with a row of metallographic papers

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just primed to size 4/0 «You will then be chemical brushed in an etching solution, the HJPO concentrated in a ratio of 3: 1. and concentrated HpSO, which contains for the duration of 2 hours is heated to 125 ° 0 ,, after two hours of etching treatment are the sub-plots washed thoroughly in hot water «,

A T-shaped quartz apparatus of Fig. 1 with an inner diameter of 45 mm was used as the deposition chamber. A quartz holder is used to hold a number of MgO crystals in the center of the cross part 4 of the apparatus • 6 were carried, the source materials contained 11 _O Each of these melting pots is carefully placed in the chamber ΐ, each source material has an individually controlled heater 7 «In this example, the source material consists of MnBr ^, FeBr ₂ and NiBr ^ ■ ^ where the substances are arranged in the stated order from top to bottom in chamber 1 «This order is determined by the temperatures» which are necessary »to evaporate the various source materials«. After that, the crystals and the containers Cross part. Been housed .4, Video- * are the, grass: adjusted flows and, on hung en JJ ^ ^ ergrund tüeke be to the desired temperature VQN about 1000 ⁰ C. The heated various heating elements 7 for the source materials 11 in the Chamber 1 will then be employed «

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The MnBr ₂ is heated to 800 ⁰ C, which PEBR ₂ to about 700 ⁰ G, and NiBr ₂ to about 60O ⁰ C.

In order to obtain the greatest possible interaction between the vapors of the source materials, mixtures of helium and argon are used to carry the vapors of the source materials and the water vapor to contact with the underground surfaces «A mixture of 141.5 liters / hour (5 cubic feet per hour) helium and 283.1 liters / hour (10 cubic feet per hour) argon are used to carry the vapors of the source materials ", a mixture of 169.8 liters / hour (6 ef ₀ p" h ₀ ) helium and 84.9 liters / hour (3 c "f _o ph">) argon is used to carry the water vapor. When the desired temperatures are reached, the carrier gases are passed back through a wash bottle containing water, causing the water vapor is carried into the reaction space. The flow rates of the liquids have been empirically determined to cause the growth of a single crystal rather than the formation of crystal nuclei. The divalent iron (Pe) becomes trivalent iron (Pe) by adding 2.26 liters / hour (0.08 cfopoho) O ₂ oxidized in the Reaktiohskammer, and at the instant the desired temperature is reached _r da "

The reaction that formed the ferrite layer was:

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0.3 MnBr ₂ ■ * - 0.55 IiBr ₂ + 2.15 FeBr ₂ + 3H ₂ O + 1/2

Mn _n ^ _n Ii _{n ςς} Fe ⁺² FeJ ³ O, + 6HBr
0.20 0, ί? 5 ο 15

100O ⁰ O

(He ₁ Ar)

As a result of this reaction an epitaxial single crystal ferrite layer or body is deposited on the MgO XJntergrund _a

An X-ray examination can be used to confirm that the ferrite layer is a single crystal is ο

The crystal is then placed in an ordinary vacuum chamber brought to deposit the first row of gold conductors through a cover that was placed on the ferrite layer This row can be deposited parallel to the (110) or (100) direction of the crystal be o

The 6-old conductors were 2 mm wide and 0.25 mm thick and were spaced 10 mm from one another on the substrate layer (spaced on 10 mil centers). The size of the conductor can be changed. The conductor cover is then removed and is replaced by a transverse cover for the deposition of insulating material on the conductors * The insulation, BaF ₂ , can be limited to the conductors at the crossing point by a cover or an equivalent device, »On the other hand, it can also cover and etch the entire row of conductors

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be to the desired establishment of Isolieruagspo.lster Manufacture «The insulation material can be deposited by any method known in the art v / earth »

Once the insulation has been deposited, a second cover is inserted into the chamber to define a second row of conductors that will cross the first row of conductors at a preselected angle. In this example, the pre-selected angle between the second row of conductors and the first was a right one, although other angles can be used _o In this way, the second row of deposited conductors crosswise overlaps the first row of conductors and is crossed by it through the previous one deposited insulation material isolated

After the second row of conductors has been deposited, the substrate with the conductors thereon is placed in the reaction deposition chamber of Fig. 1 and a second layer of single crystal ferrite is "deposited _{on top of it 9} as described above" I) the second layer of ferrite single crystals encloses together "with the" first ferrite layer on which it was deposited "the rows of conductors within the single-crystal" epitaxial ferrite, thereby providing an epitaxial ferrite storage device "of the" monocrystalline "structure of the first layer

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-20-example II

By using the apparatus and the process steps of the Example I is used, the substrate material cut so that a (110) crystallograph! sees plane the subsurface surface will, * the rows of ladders will then deposited on a ferrite layer as described above, parallel to the (001) sighting in the (110) plane or at 45 ° against that direction «, Me einkri st alline Ferrite layer was then as described in Example I. deposited, creating an epitaxial ferrite storage device is provided β ^

Example III

By the apparatus and the Yerfahrenssehritte of Example I are used, the substrate material is cut so that a (111) crystallographic plane of the substrate surface is _o i) ie conductor lines are then as described above parallel to the (111) -MiAchtung in (iii } -Mene or deposited parallel to the (1i2) -direction, whereby an epitaxial storage fermentation device is provided »» '' -.- ν, -;> ■ '.. ^. .-.'; ■ '■■ -; - , - ■ - -, - ■ .-. - -.. ■■■ · -

'■■■ "-'- ^~: -''*■" * ■ Example IV ^";' '■"^{-' :: ·:} ~

In the meantime, the apparatus and materials are used which are described in Example I »are used

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are, the temperature of the heating of the source material -was varied to controlled variations in the ferrite compositions to be obtained The temperature range of the source ranged from 500 to about 90O ⁰ C, whereby the ferrite of ferrites with high nickel and low manganese contents for low nickel and high levels of manganese. Therefore, with the right choice of temperature, the deposition can be controlled to provide a desired ferrite composition. " All temperature conditions within the range produced single crystal ferrite memory devices of acceptable grade _β

Example V

By the apparatus and the process steps which have been described in Example I were _t used, the bromides of Mn and B "i were as used in the example replaced by the bromides of Mg and Go., The modified procedure produced on an MgAl ₂ O, substrate single-crystal ferrite storage devices of acceptable quality «,

Other changes can be made without the invention from the spirit and scope of departing, "For example, both other polycrystalline materials can be used as well as other electrical conductors rows ₀ ladder or other substances can polykristailine

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be embedded or enclosed to form miniature inductors ,, Both transistors with metal base and other parts of a circuit, including integrated circuits can be formed at least in part by applying the method ₀ For example, polycrystalline precious metals, copper, and other conductive metals, Oxides, and soluble inorganic "compounds are embedded or enclosed in a similar manner in Si, Ge, GaAs, CdTe, OdS, AlgO, and MgO, the latter substances growing around such polycrystalline substances in the form of a single crystal". The invention can be used to make other devices that can tolerate encapsulation of a polycrystalline material in a single crystalline material ”.

- patent claims -

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Claims (1)

rll-i ^ 4f ^ | l 519842 -23-
-P ate η ta η s ρ r ü che to method of growing or growing a single crystal Material in addition to a polycrystalline material, characterized in that an element that polycrystalline material is deposited on a single crystal body and the single crystal material next to the polycrystalline material. and in a single crystal form, which is determined by the "single crystal body", is made to grow * 2 «Method according to claim 1, characterized in that the" monocrystalline material is a ferrite _e 3 «. Method according to claim. 1 or 2, characterized in that the polycrystalline material in ein.Einkristall is embedded or enclosed * 4ο Method according to claim 1, 2 or 3, characterized in that j αειβ. the monocrystalline material consists essentially of substances that. Formula Me '(Me''+ Fe) ₂ O * have j where Me * and Me''is at least one element from a group j that of Li, Mg, Mn * Fe, Co, M, Cu, Zn ι Cd, Al , Cr and 5? I consists _o 5i method according to claim 1, 2, 3 or 4 »thereby characterizedi that the single crystal body on a substrate is deposited and the substrate consists of either MgO or ÄlpO-z « 9 Ö 9 8 0 8/0 9 3% Z Ϊ 0 \ ^; <:: ^r '* ^: ■ " 6. The method according to claim 1, characterized in that the single crystal body and the deposited single crystal are a ferrite which, according to the formula Me ¹ (Me ¹¹ + Fe) _? O. is composed, wherein Me ^f and Me ^{11 is} at least one element from a group consisting of Li, Mg, Mn, Fe, Ni, Co, Cu, Zn, Cd, Al, Cr and Ti «, 7. The method according to claim 1, characterized in that the single crystal body and the deposited single crystal are at least one ferrite from a group consisting of MnFe ₂ O., NiFe ₂ O., MgFe ₂ O., ZnFe ₂ O. and CuFe ₂ O. , consists, 8. The method according to claim 1, 2, 3 or 4, characterized in that the single crystal body is deposited on a substrate and the substrate consists of MgO and the single crystal body and the deposited monocrystalline material of (Mn, Ni) FeFe ₂ O. consists. 9. The method according to claim 2, 6 or 7, characterized in that the ferrite by vapor deposition from the decomposition of an iron halide and a halide of at least one metal selected from a group consisting of Li, Mn, Eg, Fe, Co, Ni, Cu , Zn, Cd, Al, Cr and Ti . TO. Process according to claim 9, characterized in that the halides are the bromides of Mn, Ni and Fe 11. 909808/0933 ' 11 * Method of embedding or containment a polycrystalline electrically conductive material into a single crystalline material, characterized in that the polycrystalline material is arranged on a single crystal body and the single crystal material on the single crystal body is deposited to make the polycristalline Embed and enclose material * 12ο Method according to any one of the preceding claims, characterized in that the polycrystalline Mat'eriäl is a semiconductor material. 13 »method of any of Vora.ngega.ngenen _j claims, characterized in that the polycrystalline material is a soluble inorganic material" 14ο Method of embedding or containment of a polycrystalline electrical conductor in a Perrit single crystal, characterized in that a single ■ "...- - ■ - · ■ - ■ - '■■■: • ^{Xo'f.ts-kt':: -:} - · ■ '■. crystalline ferrite body on a monocrystalline base * At least one conductor is deposited epitaxially on the single crystal ferrite body in advance chosen magnetic orientation deposited Yfird, at least part of the first conductor is insulated, At least one second conductor is deposited across the first conductor yd.rd, eödaß the two, sigh überkretizön & ön head ' At the creation point, isolated from one another, a single crystal ferrite is deposited on the ferrite body S Oi 8 0 S / 0 9 3 S - ' _BATH so that at least a crossing point through einkrlstallines Ferrite is embedded or enclosed "