US3849193A - Method of preparation of single crystal films - Google Patents

Method of preparation of single crystal films Download PDF

Info

Publication number
US3849193A
US3849193A US00255549A US25554972A US3849193A US 3849193 A US3849193 A US 3849193A US 00255549 A US00255549 A US 00255549A US 25554972 A US25554972 A US 25554972A US 3849193 A US3849193 A US 3849193A
Authority
US
United States
Prior art keywords
constituents
crystal
solution
crystal substrate
rare earth
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.)
Expired - Lifetime
Application number
US00255549A
Inventor
B Ferrand
F Forrat
J Mareschal
Y Grange
J Joubert
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.)
Commissariat a lEnergie Atomique et aux Energies Alternatives CEA
Original Assignee
Commissariat a lEnergie Atomique CEA
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 Commissariat a lEnergie Atomique CEA filed Critical Commissariat a lEnergie Atomique CEA
Application granted granted Critical
Publication of US3849193A publication Critical patent/US3849193A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B19/00—Liquid-phase epitaxial-layer growth
    • C30B19/12—Liquid-phase epitaxial-layer growth characterised by the substrate
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G49/00—Compounds of iron
    • C01G49/0018—Mixed oxides or hydroxides
    • C01G49/0054—Mixed oxides or hydroxides containing one rare earth metal, yttrium or scandium
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B19/00—Liquid-phase epitaxial-layer growth
    • C30B19/02—Liquid-phase epitaxial-layer growth using molten solvents, e.g. flux
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
    • C30B29/10—Inorganic compounds or compositions
    • C30B29/16—Oxides
    • C30B29/22—Complex oxides
    • C30B29/28—Complex oxides with formula A3Me5O12 wherein A is a rare earth metal and Me is Fe, Ga, Sc, Cr, Co or Al, e.g. garnets
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/30—Three-dimensional structures
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/31504—Composite [nonstructural laminate]
    • Y10T428/31826—Of natural rubber
    • Y10T428/31841—Next to cellulosic
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/31504—Composite [nonstructural laminate]
    • Y10T428/31855—Of addition polymer from unsaturated monomers
    • Y10T428/3188—Next to cellulosic
    • Y10T428/31895—Paper or wood
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/31504—Composite [nonstructural laminate]
    • Y10T428/31855—Of addition polymer from unsaturated monomers
    • Y10T428/31909—Next to second addition polymer from unsaturated monomers
    • Y10T428/31913—Monoolefin polymer
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/31504—Composite [nonstructural laminate]
    • Y10T428/31855—Of addition polymer from unsaturated monomers
    • Y10T428/31931—Polyene monomer-containing
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/31504—Composite [nonstructural laminate]
    • Y10T428/31971—Of carbohydrate
    • Y10T428/31975—Of cellulosic next to another carbohydrate
    • Y10T428/31978—Cellulosic next to another cellulosic
    • Y10T428/31982—Wood or paper

Definitions

  • ABSTRACT A method of preparation of a single-crystal thin film of a rare earth mixed oxide having a garnet structure of the formula T M O where M respresents iron and T represents Yttrium.
  • a single-crystal substrate is placed in an aqueous solution which is capable of liberating the constituents of the single-crystal film in situ; the solution is brought to a high temperature in order to dissolve the constituents of the single-crystal film; and these constituents are then deposited on the single-crystal substrate by recrystallization.
  • This invention relates to a method of preparation of single-crystal films, especially thin films of mixed oxides having a garnet structure.
  • the invention applies more particularly to the preparation of films of rare-earth single-crystals, synthetic double oxides corresponding to the formula T3M5O12 in which is oxygen, M is iron which may be replaced either wholly or in part by aluminum, gallium or one of the transition elements having an atomic number within the range of 21 to 28 inclusive and in which T represents yttrium or one of the rare-earth elements having an atomic number within the range of 62 to 71, or alternatively a mixture of said rare-earth elements with each other or with yttrium.
  • the single-crystal films defined in the foregoing exhibit advantageous magnetic properties which permit their use in particular in the ultra-high frequency range (as resonant insulators, transducers, surface-wave amplifiers). These films can also be employed in logic and storage devices of the domain-displacement type.
  • One of the methods employed up to the present time for obtaining films of rare-earth single-crystals consists in growing a single crystal T M O, on a seed of T M O by hydrothermal synthesis. This method was carried out in practice as follows: the T M O was dissolved in the polycrystalline form in a 20 M sodium hydroxide solution, in the bottom portion of an autoclave which was heated to 400C; the single crystal was then recrystallized on a seed of T M O in the top portion of the autoclave which was heated to 375C.
  • Another conventional method of formation of a single-crystal film consisted in growing a single crystal of T M O, on a seed of GdGaG (gadolinium-galliumgarnet).
  • a solution of 20 M NaOH or 20 M KOH at a temperature in the vicinity of 400C was employed as solvent. But it proved difficult to apply this method to the preparation of thin films since the seed was frequently attacked by the solvent.
  • the dissolution of the polycrystal T M O in the ammonium chloride was a very slow process, the seed of GdGaG was attacked by NH Cl and the single-crystal deposit was not uniform.
  • the method according to the invention overcomes the disadvantages recalled in the foregoing, especially insofar as it permits rapid dissolution of the constituents of the single crystal and consequently results in thin and homogeneous single-crystal films.
  • One of the advantages ofthc invention lies in the fact that a singlecrystal film can be deposited on a single-crystal substrate having a different chemical composition.
  • the method under consideration is primarily distinguished by the fact that a single-crystal substrate is placed in an aqueous solution which contains compounds having a base of constituents destined to form the single-crystal film and which is capable ofliberating said constituents in situ, said solution is brought to a high temperature so as to dissolve said constituents, and said constituents are then deposited by recrystallization on said single-crystal substrate.
  • thin single crystal films of a rare-earth mixed oxide having a garnet structure, and corresponding to the formula T M O as hereinabove defined. are deposited on a single-crystal substrate consisting of gadoliniumgallium-garnet-(GdGaG).
  • composition is not intended to imply any limitation of the invention and the method can be employed for any other deposition of a single-crystal film of mixed oxides having a garnet structure on a predetermined single-crystal substrate.
  • the method can also be applied to the preparation of single-crystal thin films of different magnetic compounds of garnets such as, for example, the orthoferrites of rare earths or the spinel ferrites.
  • the method according to the invention is carried out in an autoclave of heat-resisting steel lined with platinum, gold or silver.
  • This autoclave is hermetically sealed by means of a system of gaskets of the Bridgman type and connected to a manometer by a highpressure flexible capillary wire.
  • the autoclave is placed in a furnace having two separate heating zones which are regulated independently in order that it may thus be possible to control the temperature difference between the top and the bottom of the autoclave.
  • the constituents which are intended to yield in situ the mixed oxide having a garnet structure by double decomposition are placed in an aqueous solution in the bottom of the autoclave which is the hot portion,
  • the single-crystal substrate is placed in the top of the autoclave which is the cold portion,
  • the aqueous solution is brought to a high temperature and high pressure in such manner as to decompose and dissolve the constituents of the mixed oxide, then to transport them into the cold portion of the autoclave in which they crystallize on the single-crystal substrate.
  • the temperature difference existing within the autoclave gives rise to convection currents which facilitate the transport of material from the hot portion to the cold portion.
  • the aqueous solution is constituted by a solution of a mixed salt of a metal and of an alkali metal and a hydroxide or a salt of rare earth or of yttrium.
  • a mixed salt of a metal and of an alkali metal and a hydroxide or a salt of rare earth or of yttrium for example, it is possible to employ NaFeO or KFeO and Y (Oi-U Double decomposition results in formation on the one hand of sodium hydroxide or of potassium having a low concentration which acts as transporting and mineralizing agent and on the other hand of single-crystal film constituents which will be deposited on the single-crystal substrate.
  • the aqueous solution is constituted by a solution of a mixed salt of rare earth or of yttrium and of an alkali metal and a hydroxide or a salt of a metal.
  • the operational temperature is within the range of 450C to 550C. A temperature difference of 20C to 70C is maintained between the bottom portion and the top portion of the autoclave.
  • the coefficient of filling in the autoclave is 0.4 to 0.6.
  • EXAMPLE Use is made of an autoclave having a useful volume of 130 cm and lined with silver.
  • the autoclave is closed and placed in a furnace having two temperature zones in order that the bottom portion of the autoclave should be at a temperature of 500C and that the top portion should be at a temperature of 450C.
  • the pressure is then 600 bars.
  • the seeding process is carried out for a period of 24 hours.
  • T being a substance selected from the group consisting of the rare earth elements having an atomic number within the range of 62 to 71.
  • the aqueous solution being a solution of a mixed salt of a metal and of an alkali metal and a hydroxide or a salt of rare earth or of yttrium.
  • the aqueous solution being a solution of a mixed salt of rare earth or of yttrium and of an alkali metal and a hydroxide or a salt of a metal.

Abstract

A method of preparation of a single-crystal thin film of a rare earth mixed oxide having a garnet structure of the formula T3M5O12 where M respresents iron and T represents Yttrium. A single-crystal substrate is placed in an aqueous solution which is capable of liberating the constituents of the single-crystal film in situ; the solution is brought to a high temperature in order to dissolve the constituents of the single-crystal film; and these constituents are then deposited on the single-crystal substrate by recrystallization.

Description

Ferrand et al.
Commissariat a lEnergie Atomique, Paris, France Filed: May 22, 1972 Appl. No.: 255,549
Assignee:
Foreign Application Priority Data May 25, 1971 France 71.18889 US. Cl 117/235, 117/113, 423/263, 423/594 Int. Cl. H011 10/02 Field of Search 117/235-240, 117/113, 65.2; 423/594, 263
References Cited UNITED STATES PATENTS 7/1962 Stoller et al. 117/235 Nov. 19, 1974 3,100,158 8/1963 Lemaire et a1 ll7/235 X 3,404,026 10/1968 Skudera et al. 117/235 UX 3,429,740 2/1969 Mee 117/235 X 3,486,937 12/1969 Linares 117/235 X 3,573,099 3/1971 Moore et al. 117/235 X 3,607,390 9/1971 Comstock 117/235 X 3,697,320 10/1972 Hiskes 117/235 X Primary ExaminerWilliam D. Martin Assistant Examiner-Bernard D. Pianalto Attorney, Agent, or FirmCameron, Kerkam, Sutton, Stowell & Stowell [5 7] ABSTRACT A method of preparation of a single-crystal thin film of a rare earth mixed oxide having a garnet structure of the formula T M O where M respresents iron and T represents Yttrium. A single-crystal substrate is placed in an aqueous solution which is capable of liberating the constituents of the single-crystal film in situ; the solution is brought to a high temperature in order to dissolve the constituents of the single-crystal film; and these constituents are then deposited on the single-crystal substrate by recrystallization.
10 Claims, No Drawings METHOD OF PREPARATION OF SINGLE CRYSTAL FILMS This invention relates to a method of preparation of single-crystal films, especially thin films of mixed oxides having a garnet structure.
The invention applies more particularly to the preparation of films of rare-earth single-crystals, synthetic double oxides corresponding to the formula T3M5O12 in which is oxygen, M is iron which may be replaced either wholly or in part by aluminum, gallium or one of the transition elements having an atomic number within the range of 21 to 28 inclusive and in which T represents yttrium or one of the rare-earth elements having an atomic number within the range of 62 to 71, or alternatively a mixture of said rare-earth elements with each other or with yttrium.
The single-crystal films defined in the foregoing exhibit advantageous magnetic properties which permit their use in particular in the ultra-high frequency range (as resonant insulators, transducers, surface-wave amplifiers). These films can also be employed in logic and storage devices of the domain-displacement type.
One of the methods employed up to the present time for obtaining films of rare-earth single-crystals consists in growing a single crystal T M O, on a seed of T M O by hydrothermal synthesis. This method was carried out in practice as follows: the T M O was dissolved in the polycrystalline form in a 20 M sodium hydroxide solution, in the bottom portion of an autoclave which was heated to 400C; the single crystal was then recrystallized on a seed of T M O in the top portion of the autoclave which was heated to 375C.
Another conventional method of formation of a single-crystal film consisted in growing a single crystal of T M O, on a seed of GdGaG (gadolinium-galliumgarnet). A solution of 20 M NaOH or 20 M KOH at a temperature in the vicinity of 400C was employed as solvent. But it proved difficult to apply this method to the preparation of thin films since the seed was frequently attacked by the solvent. There was also employed as solvent a percent solution of NH Cl at temperatures in the vicinity of 550C. However, the dissolution of the polycrystal T M O in the ammonium chloride was a very slow process, the seed of GdGaG was attacked by NH Cl and the single-crystal deposit was not uniform.
The method according to the invention overcomes the disadvantages recalled in the foregoing, especially insofar as it permits rapid dissolution of the constituents of the single crystal and consequently results in thin and homogeneous single-crystal films. One of the advantages ofthc invention lies in the fact that a singlecrystal film can be deposited on a single-crystal substrate having a different chemical composition.
The method under consideration is primarily distinguished by the fact that a single-crystal substrate is placed in an aqueous solution which contains compounds having a base of constituents destined to form the single-crystal film and which is capable ofliberating said constituents in situ, said solution is brought to a high temperature so as to dissolve said constituents, and said constituents are then deposited by recrystallization on said single-crystal substrate.
In a preferred mode of execution of the invention, thin single crystal films of a rare-earth mixed oxide having a garnet structure, and corresponding to the formula T M O as hereinabove defined. are deposited on a single-crystal substrate consisting of gadoliniumgallium-garnet-(GdGaG).
It will be readily understood that this composition is not intended to imply any limitation of the invention and the method can be employed for any other deposition of a single-crystal film of mixed oxides having a garnet structure on a predetermined single-crystal substrate. The method can also be applied to the preparation of single-crystal thin films of different magnetic compounds of garnets such as, for example, the orthoferrites of rare earths or the spinel ferrites.
The method according to the invention is carried out in an autoclave of heat-resisting steel lined with platinum, gold or silver. This autoclave is hermetically sealed by means of a system of gaskets of the Bridgman type and connected to a manometer by a highpressure flexible capillary wire. The autoclave is placed in a furnace having two separate heating zones which are regulated independently in order that it may thus be possible to control the temperature difference between the top and the bottom of the autoclave.
The method is carried into effect as follows:
The constituents which are intended to yield in situ the mixed oxide having a garnet structure by double decomposition are placed in an aqueous solution in the bottom of the autoclave which is the hot portion,
The single-crystal substrate is placed in the top of the autoclave which is the cold portion,
The aqueous solution is brought to a high temperature and high pressure in such manner as to decompose and dissolve the constituents of the mixed oxide, then to transport them into the cold portion of the autoclave in which they crystallize on the single-crystal substrate.
The temperature difference existing within the autoclave gives rise to convection currents which facilitate the transport of material from the hot portion to the cold portion.
In accordance with one advantageous feature of the method forming the subject of this invention, the aqueous solution is constituted by a solution of a mixed salt of a metal and of an alkali metal and a hydroxide or a salt of rare earth or of yttrium. For example, it is possible to employ NaFeO or KFeO and Y (Oi-U Double decomposition results in formation on the one hand of sodium hydroxide or of potassium having a low concentration which acts as transporting and mineralizing agent and on the other hand of single-crystal film constituents which will be deposited on the single-crystal substrate.
In accordance with another feature of the method which forms the subject of the invention, the aqueous solution is constituted by a solution of a mixed salt of rare earth or of yttrium and of an alkali metal and a hydroxide or a salt of a metal.
For example, it is possible to carry out a double decomposition reaction between NaFeO and an yttrium salt such as, for example, YCI 6 H O; Y (N09 The salts which are formed, namely NaCl, NaNO accordingly act as transporting and mineralizing agents. It is also possible to carry out a double decomposition reaction between YNaO or YKO and newly precipitated Fe (OH) or a ferric salt such as, for example, FeCl Fe (N09 Fe (SO In the method according to the invention, the operational temperature is within the range of 450C to 550C. A temperature difference of 20C to 70C is maintained between the bottom portion and the top portion of the autoclave.
The coefficient of filling in the autoclave is 0.4 to 0.6.
One example of application of the method according to the invention is given hereinafter without any implied limitation.
EXAMPLE Use is made of an autoclave having a useful volume of 130 cm and lined with silver.
There are placed at the bottom of said autoclave 6 g of NaFeO 2.5 g of Y(OH) and a sodium hydroxide solution consisting of 2.6 g of caustic soda in 60 cm of water.
There is then fitted in position a platinum frame provided with a central screen having an opening of 20 percent.
At the top of said frame, there is placed a seed of Gd Ga 0. which is cut at right angles to the direction (1, l,
The autoclave is closed and placed in a furnace having two temperature zones in order that the bottom portion of the autoclave should be at a temperature of 500C and that the top portion should be at a temperature of 450C.
The pressure is then 600 bars. The seeding process is carried out for a period of 24 hours.
At the end of this period, the autoclave is cooled rapidly and there is thus obtained a thin single-crystal film of Y Fe O, having a thickness of 2.5 11..
What we claim is:
l. A method of preparation of a single-crystal thin film of a rare earth mixed oxide having a garnet structure of the formula T M O where M represents iron and T represents yttrium, the steps of placing a singlecrystal substrate in an aqueous solution in an autoclave which contains compounds having a base of Constituents to form the single-crystal film by liberating said constituents in situ by double decomposition, bringing said solution to a high temperature and high pressure to dissolve said constituents and then depositing said constituents by recrystallization on said single-crystal substrate, a temperature difference within the range of 20C to C being maintained between dissolution and deposition of the constituents.
2. A method according to claim 1, the coefficient of filling of the autoclave being between 0.4 to 0.6.
3. A method according to claim 1, the iron being at least partially replaced by a substance selected from the group consisting of aluminum, gallium and the transition elements having an atomic number within the range of 21 to 28 inclusive.
4. A method according to claim 1, T being a substance selected from the group consisting of the rare earth elements having an atomic number within the range of 62 to 71.
5. A method according to claim 1, the single-crystal substrate having a chemical composition different from that of the single-crystal film.
6. A method according to claim 1, the single-crystal substrate being gadolinium-gallium-garnet.
7. A method according to claim 1, the aqueous solution being a solution of a mixed salt of a metal and of an alkali metal and a hydroxide or a salt of rare earth or of yttrium.
8. A method according to claim 1, the aqueous solution being a solution of a mixed salt of rare earth or of yttrium and of an alkali metal and a hydroxide or a salt of a metal.
9. A method a-cording to claim 8, wherein the solution contains NaFeO and YCl 6H O.
10. A method according to claim 1, the high temperature being between 400C. and 550C.

Claims (10)

1. A METHOD OF PREPARATION OF A SINGLE-CRYSTAL THIN FILM OF A RARE EARTH MIXED OXIDE HAVING A GARNET STRUCTURE OF THE FORMULA T3M5O12 WHERE M REPRESENTS IRON AND T REPRESENTS YTTRIUM, THE STEPS OF PLACING A SINGLE-CRYSTAL SUBSTRATE IN AN AQUEOUS SOLTUION IN AN AUTOCLAVE WHICH CONTAINS COMPOUND HAVING A BASE OF CONSTITUENTS TO FORM THE SINGLE-CRYSTAL FILM BY LIBERATING SAID CONSTITUENTS IN SITU BY DOUBLE DECOMPOSITION, BRINGING SAID SOLUTION TO A HIGH TEMPERATURE AND HIGH PRESSURE TO DISSOLVE SAID CONSTITUENTS AND THEN DEPOSITING SAID CONSTITUENTS BY RECRYSTALLIZATION ON SAID SINGLE-CRYSTAL SUBSTRATE, A TEMPERATURE DIFFERENCE WITHIN THE RANGE OF 20*C TO 70*C BEING MAINTANED BETWEEN DISSOLUTION AND DEPOSITION OF THE CONSTITUENTS.
2. A method according to claim 1, the coefficient of filling of the autoclave being between 0.4 to 0.6.
3. A method according to claim 1, the iron being at least partially replaced by a substance selected from the group consisting of aluminum, gallium and the transition elements having an atomic number within the range of 21 to 28 inclusive.
4. A method according to claim 1, T being a substance selected from the group consisting of the rare earth elements having an atomic number within the range of 62 to 71.
5. A method according to claim 1, the single-crystal substrate having a chemical composition different from that of the single-crystal film.
6. A method according to claim 1, the single-crystal substrate being gadolinium-gallium-garnet.
7. A method according to claim 1, the aqueous solution being a solution of a mixed salt of a metal and of an alkali metal and a hyDroxide or a salt of rare earth or of yttrium.
8. A method according to claim 1, the aqueous solution being a solution of a mixed salt of rare earth or of yttrium and of an alkali metal and a hydroxide or a salt of a metal.
9. A method a-cording to claim 8, wherein the solution contains NaFeO2 and YCl2, 6H2O.
10. A method according to claim 1, the high temperature being between 400*C. and 550*C.
US00255549A 1971-05-25 1972-05-22 Method of preparation of single crystal films Expired - Lifetime US3849193A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR717118889A FR2138410B1 (en) 1971-05-25 1971-05-25

Publications (1)

Publication Number Publication Date
US3849193A true US3849193A (en) 1974-11-19

Family

ID=9077594

Family Applications (1)

Application Number Title Priority Date Filing Date
US00255549A Expired - Lifetime US3849193A (en) 1971-05-25 1972-05-22 Method of preparation of single crystal films

Country Status (6)

Country Link
US (1) US3849193A (en)
CA (1) CA968677A (en)
FR (1) FR2138410B1 (en)
GB (1) GB1384745A (en)
IL (1) IL39507A (en)
IT (1) IT958962B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2120147C1 (en) * 1996-09-06 1998-10-10 Акционерное общество закрытого типа "Тетра" Thin-film magnetic material

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3047429A (en) * 1959-03-27 1962-07-31 Rca Corp Magnetic recording medium comprising coatings of ferrite particles of the molar composite amno.bzno.cfe2o3
US3100158A (en) * 1960-11-02 1963-08-06 Rca Corp Methods for obtaining films of magnetic spinel crystals on substrates
US3404026A (en) * 1965-04-06 1968-10-01 Army Usa Method of forming magnetic ferrite films
US3429740A (en) * 1965-09-24 1969-02-25 North American Rockwell Growing garnet on non-garnet single crystal
US3486937A (en) * 1967-03-24 1969-12-30 Perkin Elmer Corp Method of growing a single crystal film of a ferrimagnetic material
US3573099A (en) * 1969-12-22 1971-03-30 Ibm Process for making garnet films
US3607390A (en) * 1969-09-29 1971-09-21 Ibm Single crystal ferrimagnetic films
US3697320A (en) * 1971-01-11 1972-10-10 Hewlett Packard Co Method and flux for growing single crystals of garnet or ortho ferrites

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1544556A (en) * 1966-11-15 1968-10-31 Western Electric Co Method of growing magnetic garnets and materials thus obtained

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3047429A (en) * 1959-03-27 1962-07-31 Rca Corp Magnetic recording medium comprising coatings of ferrite particles of the molar composite amno.bzno.cfe2o3
US3100158A (en) * 1960-11-02 1963-08-06 Rca Corp Methods for obtaining films of magnetic spinel crystals on substrates
US3404026A (en) * 1965-04-06 1968-10-01 Army Usa Method of forming magnetic ferrite films
US3429740A (en) * 1965-09-24 1969-02-25 North American Rockwell Growing garnet on non-garnet single crystal
US3486937A (en) * 1967-03-24 1969-12-30 Perkin Elmer Corp Method of growing a single crystal film of a ferrimagnetic material
US3607390A (en) * 1969-09-29 1971-09-21 Ibm Single crystal ferrimagnetic films
US3573099A (en) * 1969-12-22 1971-03-30 Ibm Process for making garnet films
US3697320A (en) * 1971-01-11 1972-10-10 Hewlett Packard Co Method and flux for growing single crystals of garnet or ortho ferrites

Also Published As

Publication number Publication date
CA968677A (en) 1975-06-03
FR2138410B1 (en) 1973-05-25
IL39507A (en) 1976-05-31
IT958962B (en) 1973-10-30
GB1384745A (en) 1975-02-19
IL39507A0 (en) 1972-07-26
FR2138410A1 (en) 1973-01-05

Similar Documents

Publication Publication Date Title
Blank et al. The growth of magnetic garnets by liquid phase epitaxy
Teague et al. Dielectric hysteresis in single crystal BiFeO3
Shafer Preparation and crystal chemistry of divalent europium compounds
SAVAGE et al. Growth and properties of single crystals of hexagonal ferrites
US2957827A (en) Method of making single crystal garnets
Tressler et al. Pressure‐Temperature Study of Sulfospinels
Laudise et al. Hydrothermal crystallization of yttrium‐iron garnet on a seed
Kolb et al. The hydrothermal growth of rare earth orthoferrites
US2879154A (en) Acicular metal particles and method of making the same
US3429740A (en) Growing garnet on non-garnet single crystal
Glass et al. Growth and characterization of LPE hexagonal ferrites
Harbison et al. MBE growth of ferromagnetic metastable epitaxial MnAl thin films on AlAs/GaAs heterostructures
Laudise et al. The hydrothermal crystallization of yttrium iron garnet and yttrium gallium garnet and a part of the crystallization diagram Y2O3—Fe2O3—H2O—Na2CO3
US3849193A (en) Method of preparation of single crystal films
Kolb et al. Hydrothermal growth of hematite and magnetite
Soxman Hollow crystals of hexagonal ZnS
Brunner Hydrothermal and supercritical water processing of inorganic substances
Chai et al. Synthesis of rare-earth carbonates under hydrothermal conditions
US4671885A (en) Process for the preparation of magnetized hexagonal ferrites, use of these ferrites as base materials for magnets or for magnetic recording
Nielsen Properties and preparation of magnetic materials for bubble domains
Lefever et al. Synthetic emerald
DE3064319D1 (en) Process for producing polycrystalline garnet comprising aluminium and/or gallium and/or indium and at least one element of the group constituted by the rare earths and yttrium, polycrystalline garnet thus obtained
Gibart et al. Epitaxial growth of ferrite
US4499061A (en) Strontium ferrite borate
US3846322A (en) Method of producing large single crystals of mixed ferrites