WO2024016379A1 - 一种多铁薄膜前驱体及其制备方法和制得的柔性多铁薄膜 - Google Patents

一种多铁薄膜前驱体及其制备方法和制得的柔性多铁薄膜 Download PDF

Info

Publication number
WO2024016379A1
WO2024016379A1 PCT/CN2022/109488 CN2022109488W WO2024016379A1 WO 2024016379 A1 WO2024016379 A1 WO 2024016379A1 CN 2022109488 W CN2022109488 W CN 2022109488W WO 2024016379 A1 WO2024016379 A1 WO 2024016379A1
Authority
WO
WIPO (PCT)
Prior art keywords
multiferroic
film
salt
cofe
flexible
Prior art date
Application number
PCT/CN2022/109488
Other languages
English (en)
French (fr)
Inventor
任传来
安峰
钟高阔
李江宇
Original Assignee
深圳先进技术研究院
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 深圳先进技术研究院 filed Critical 深圳先进技术研究院
Publication of WO2024016379A1 publication Critical patent/WO2024016379A1/zh

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G49/00—Compounds of iron
    • C01G49/009—Compounds containing, besides iron, two or more other elements, with the exception of oxygen or hydrogen
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G23/00—Compounds of titanium
    • C01G23/003—Titanates
    • C01G23/006—Alkaline earth titanates
    • 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
    • C01G49/0036—Mixed oxides or hydroxides containing one alkaline earth metal, magnesium or lead
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G51/00—Compounds of cobalt
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G55/00—Compounds of ruthenium, rhodium, palladium, osmium, iridium, or platinum
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N50/00—Galvanomagnetic devices
    • H10N50/01—Manufacture or treatment
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N50/00—Galvanomagnetic devices
    • H10N50/80—Constructional details
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N50/00—Galvanomagnetic devices
    • H10N50/80—Constructional details
    • H10N50/85—Magnetic active materials
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
    • C01P2002/72—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by d-values or two theta-values, e.g. as X-ray diagram

Definitions

  • the present application relates to the field of microelectronic devices, and more specifically, it relates to a multiferroic film precursor, its preparation method and the prepared flexible multiferroic film.
  • Multi-state memories based on multiferroic magnetoelectric materials
  • Software can store multiple information states in one storage unit, can increase storage capacity exponentially, and has the advantages of fast reading and writing speed, long data storage time, and low power consumption.
  • this application provides a multiferroic film precursor, a preparation method thereof, and a prepared flexible multiferroic film.
  • this application provides a multiferroic film precursor, adopting the following technical solution:
  • a multiferroic film precursor is prepared from a metal salt, a complexing agent, and a solvent.
  • the metal salt includes an ion molar ratio of (0.8-0.9): (0.64-0.72): (0.08-0.09): (0.1- 0.2): (0.19-0.28) bismuth salt, iron salt, magnesium salt, calcium salt and titanium salt.
  • the complex reaction By using the above types to prepare the multiferroic film precursor, and controlling the type of metal salt and the ion molar ratio, the complex reaction generates (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 under the action of the complexing agent.
  • Iron film precursor used in the preparation of flexible films, can form a uniform and stable multiferroic functional layer.
  • the doping of Ti, Mg and other elements of the B-site cation can stabilize the structure of the Bi-based perovskite, making (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 multiferroic
  • the functional layer solid solution has strong ferroelectric polarization and room-temperature weak ferromagnetism near the quasi-isotropic phase boundary, that is, it has room-temperature multiferroicity, and its magnetism and magnetoelectric coupling effects are enhanced.
  • the metal salt is composed of bismuth salt, iron salt and magnesium salt with an ion molar ratio of (0.8-0.9): (0.64-0.72): (0.08-0.09): (0.1-0.2): (0.19-0.28) , calcium salt and titanium salt.
  • the molar concentration of the multiferroic film precursor is 0.1-0.4moL/L; the addition amount of the complexing agent is 23-25% of the metal salt.
  • the metal salts can be complexed to form a stable (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 multiferroic film.
  • the precursor when applied to the preparation of flexible films, can be uniformly spin-coated on the surface of the bottom electrode layer. After pre-annealing and annealing, a stable multiferroic functional layer can be formed, which can exhibit ferroelectricity and magnetism at room temperature.
  • the solvent is ethylene glycol methyl ether
  • the complexing agent is citric acid
  • the bismuth salt is bismuth nitrate pentahydrate
  • the iron salt is ferric nitrate nonahydrate
  • the magnesium salt is nitric acid hexahydrate.
  • Magnesium the calcium salt is calcium acetate monohydrate
  • the titanium salt is tetrabutyl titanate.
  • the complexation of the metal salts can be promoted to form a stable multiferroic film precursor system, which can be evenly coated on the surface of the bottom electrode layer during the preparation of the flexible film to form a room temperature A multiferroic thin film with excellent ferroelectricity and magnetism at the same time, and a coupling of linear magnetoelectric effects.
  • this application provides a method for preparing a multiferroic film precursor, adopting the following technical solution:
  • the (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 multiferroic film precursor is produced, which has stable quality and is easy to coat and prepare. flexible film.
  • this application provides a flexible multiferroic film that adopts the following technical solution:
  • a flexible multiferroic film including a flexible substrate and a buffer layer, a bottom electrode layer and a multiferroic functional layer arranged in sequence from bottom to top on the surface of the flexible substrate;
  • the flexible substrate is a mica substrate, and the buffer layer
  • the layer is a CoFe 2 O 4 thin film layer
  • the bottom electrode layer is a SrRuO 3 thin film layer
  • the multiferroic functional layer is a (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 thin film layer
  • the mica substrate used has excellent flexibility and thermal stability, so that the multiferroic film produced has excellent flexibility, and the thermal stability of the mica substrate can be used to prepare CoFe 2 O 4 films, SrRuO 3 films, (1-x )BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 thin film process, the mica substrate is not easily heated and causes quality damage.
  • a CoFe 2 O 4 film, a SrRuO 3 film, a (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 film, and (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 - are arranged in sequence.
  • xCaTiO 3 thin films can be epitaxially grown with CoFe 2 O 4 thin films and SrRuO 3 thin films, with good lattice matching and high film formation quality.
  • the flexible multiferroic thin films that can be produced can not only have good ferroelectricity and Magnetic and has linear magnetoelectric effect coupling; and can control the polarization domain state of the flexible multiferroic film by adjusting the external magnetic field to achieve eight logical storage states (000, 001, 010, 011, 100, 101, 110 and 111 ).
  • the thickness of the buffer layer is 10-20 nm
  • the thickness of the bottom electrode layer is 25-50 nm
  • the thickness of the multiferroic functional layer is 30-80 nm.
  • the prepared flexible multiferroic film can be thinner, more flexible, and have both excellent ferroelectricity and magnetism at room temperature. And it has the coupling of linear magnetoelectric effect.
  • this application provides a method for manufacturing a flexible multiferroic film, adopting the following technical solution:
  • a method for manufacturing a flexible multiferroic film including the following steps:
  • the preparation of the CoFe 2 O 4 thin film and the SrRuO 3 thin film in this application are preferably prepared by using a pulse laser deposition process.
  • the pulse laser deposition process refers to using a high-power pulse laser generated by a pulse laser to ablate a target made of the required material. On the surface of the material, high-temperature and high-pressure plasma is generated. The plasma expands and emits towards the substrate surface in the deposition atmosphere, and is deposited on the substrate to form a thin film.
  • the CoFe 2 O 4 thin film can be stably deposited on the surface of the flexible substrate, and the SrRuO 3 thin film can be stably deposited on the surface of the CoFe 2 O 4 thin film; and , the SrRuO 3 film has good electrical conductivity and stable structure, so that the (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 film can be directly epitaxially grown on the surface of the SrRuO 3 film by spin coating and annealing treatment, and, SrRuO 3 film and (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 film are both perovskite structures and have similar lattice parameters, making (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 film achieves epitaxial growth with CoF
  • the (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 multiferroic film precursor is directly spin-coated onto the surface of the SrRuO 3 film by spin coating, combined with pre-annealing treatment and annealing treatment, to reduce (1-x)
  • the defects inside the BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 film improve the interlayer bonding between the (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 film and the SrRuO 3 film.
  • the CoFe 2 O 4 film is specifically prepared using pulsed laser deposition, using the CoFe 2 O 4 target as the laser target, the target-base distance is 65-75mm, and the laser energy is 300-350mJ.
  • the laser wavelength is 230-250nm
  • the heating temperature of the flexible substrate is 580-620°C
  • the deposition atmosphere is 25-55mTorr oxygen
  • the deposition time is 4-7min.
  • the CoFe 2 O 4 film can be stably generated on the surface of the flexible substrate, and the CoFe 2 O 4 film is stably combined with the surface of the flexible substrate. .
  • a pulsed laser deposition method is used to prepare the SrRuO 3 film, the SrRuO 3 target is used as the laser target, the target-base distance is 65-75mm, the laser energy is 300-350mJ, and the laser wavelength is 230-250nm, the heating temperature of the flexible substrate is 585-615°C, the deposition atmosphere is 70-90mTorr oxygen, and the deposition time is 5-10min.
  • the SrRuO 3 film can be stably generated on the surface of the flexible substrate, and the SrRuO 3 film is stably combined with the surface of the CoFe 2 O 4 film.
  • the operation of spin coating the precursor solution on the surface of the bottom electrode layer of the mica/CFO/SRO composite film is to first spin coating at a rotation speed of 550-650 rpm for 6-10 s, and then Spin coating at 3800-4200 rpm for 35-45 seconds.
  • the surface of the bottom electrode layer of the mica/CoFe 2 O 4 /SrRuO 3 composite film can be evenly spin-coated.
  • Iron thin film precursor Specifically, the (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 multiferroic functional layer of the present application is prepared by coating the surface of the SrRuO 3 film generated by pulse laser deposition with a multiferroic thin precursor and then annealing it. The SrRuO 3 film is generated by pulsed laser deposition.
  • the (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 multiferroic film precursor can be Evenly coated, it can grow epitaxially along the crystal lattice of the SrRuO 3 film, making the surface of the prepared flexible multiferroic film smooth.
  • the specific operation is to first place the mica/CoFe 2 O 4 /SrRuO 3 composite film stably on the suction cup of the glue leveling machine, and then drop the (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 multiferroic film precursor.
  • the rotation speed of low-speed spin coating and the rotation speed of high-speed spin coating are both the rotation speed of the set glue leveler.
  • the pre-annealing treatment is performed by first heating to 120-150°C within 4-7 minutes, and then maintaining the temperature at 360-400°C for 8-12 minutes.
  • the annealing treatment is performed by first heating to 430-480°C within 4-7 minutes, and then maintaining the temperature at 790-810°C for 13-17 minutes.
  • the (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 multiferroic film precursor can be fully crystallized to form (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 film, and has good combination with SrRuO 3 film.
  • the prepared (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 film can be epitaxially combined with SrRuO 3 film and CoFe 2 O 4 film growth, good lattice matching, and high film quality.
  • the precursor may not be fully crystallized.
  • the surface of the (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 film may be over-annealed and internal defects may exist, resulting in (1 -x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 film has low bonding ability with SrRuO 3 film.
  • the pre-annealing treatment and annealing treatment process of the present application maintain flowing high-purity oxygen, specifically high-purity oxygen with a concentration greater than 99.999%.
  • the multiferroic film precursor of the present application when used in the preparation of flexible films, can form a uniform and stable multiferroic functional layer, and can make the multiferroic functional layer have strong ferroelectric polarization and room temperature weak ferromagnetism, that is, it has Room-temperature multiferroic and enhanced magnetism and magnetoelectric coupling effects.
  • the mica substrate used in this application has excellent flexibility and thermal stability.
  • CoFe 2 O 4 film, SrRuO 3 film, (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 - can be sequentially placed on the surface of the mica substrate.
  • xCaTiO 3 film, the flexible multiferroic film that can be produced not only has good ferroelectricity and magnetism at room temperature, but also has the coupling of linear magnetoelectric effects; and can control the polarization of the flexible multiferroic film by adjusting the external magnetic field.
  • Domain state realizing eight logical storage states (000, 001, 010, 011, 100, 101, 110 and 111).
  • the pulse laser deposition process is preferably used to prepare the CoFe 2 O 4 film and the SrRuO 3 film, which can enable the CoFe 2 O 4 film to be stably deposited on the surface of the flexible substrate, and the SrRuO 3 film to be formed on the CoFe 2 O 4 film.
  • the SrRuO 3 film has good conductivity and stable structure, allowing direct epitaxial growth of (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO on the surface of the SrRuO 3 film using spin coating and annealing treatments 3 thin film, it can also achieve epitaxial growth of (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 thin film, CoFe 2 O 4 thin film, and SrRuO 3 thin film, with good lattice matching and high film formation quality.
  • the (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 thin film is prepared by directly applying the (1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 precursor solution by spin coating.
  • Figure 1 is the X-ray diffraction (XRD) spectrum of the flexible multiferroic film prepared in Application Example 3 of the present application;
  • Figure 2 is a piezoelectric force microscope test result of the flexible multiferroic film produced in Application Example 3 of the present application;
  • Figure (a) is the morphology after applying a voltage of 8V, and
  • Figure (b) is the amplitude after applying a voltage of 8V Figure,
  • (c) is the phase diagram after applying a voltage of 8V;
  • Figure 3 is a graph showing the polarization domain test results of the flexible multiferroic film produced in Application Example 3 of the present application under different magnetic fields;
  • Figure 4 is a schematic diagram of eight logical storage states of the flexible multiferroic film produced in Application Example 3 of this application.
  • a flexible multiferroic film including a mica substrate and a CoFe 2 O 4 film layer, a SrRuO 3 film layer and a 0.9BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -0.1CaTiO 3 film layer arranged sequentially from bottom to top on the surface of the mica substrate. ;
  • Its manufacturing method includes the following steps:
  • the SrRuO 3 target is used as the laser target through pulsed laser deposition.
  • the target-base distance is 70mm
  • the laser energy is 330mJ
  • the laser wavelength is 248nm
  • the heating temperature of the flexible substrate is 600°C
  • the deposition atmosphere is 80mTorr oxygen
  • the deposition time is 7 minutes
  • a SrRuO 3 film layer with a thickness of 46nm is deposited and grown on the surface of the CoFe 2 O 4 film layer to prepare mica/CoFe 2 O 4 /SrRuO 3 composite film;
  • the mica/CoFe 2 O 4 /SrRuO 3 composite film spin-coated with the precursor solution is heated to 120°C within 5 minutes, and then kept at 380°C for 10 minutes to perform pre-annealing treatment; then heated to 450°C within 5 minutes. °C, then keep it at 800°C for 15 minutes, and perform annealing treatment. Keep flowing high-purity oxygen throughout the pre-annealing treatment and annealing treatment, and then crystallize on the surface of the SrRuO 3 film layer of the mica/CoFe 2 O 4 /SrRuO 3 composite film.
  • a flexible multiferroic film is obtained by preparing a 0.9BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -0.1CaTiO 3 film layer with a thickness of 46nm.
  • a flexible multiferroic film including a mica substrate and a CoFe 2 O 4 film layer, a SrRuO 3 film layer and a 0.8BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -0.2CaTiO 3 film layer arranged sequentially from bottom to top on the surface of the mica substrate. ;
  • Its manufacturing method includes the following steps:
  • the SrRuO 3 target is used as the laser target through pulsed laser deposition.
  • the target-base distance is 65mm
  • the laser energy is 330mJ
  • the laser wavelength is 248nm
  • the heating temperature of the flexible substrate is 600°C
  • the deposition atmosphere is 80mTorr oxygen
  • the deposition time is 6 minutes
  • a SrRuO 3 film layer with a thickness of 30nm is deposited and grown on the surface of the CoFe 2 O 4 film layer to prepare mica/CoFe 2 O 4 /SrRuO 3 composite film;
  • the mica/CoFe 2 O 4 /SrRuO 3 composite film spin-coated with the precursor solution is heated to 120°C within 5 minutes, and then kept at 380°C for 10 minutes to perform pre-annealing treatment; then heated to 450°C within 5 minutes. °C, and then kept at 810°C for 15 minutes, and then annealed.
  • the entire pre-annealing treatment and annealing treatment kept flowing high-purity oxygen, and then crystallized on the surface of the SrRuO 3 film layer of the mica/CoFe 2 O 4 /SrRuO 3 composite film.
  • a flexible multiferroic film is obtained by preparing a 0.8BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -0.2CaTiO 3 film layer with a thickness of 40nm.
  • a flexible multiferroic film including a mica substrate and a CoFe 2 O 4 film layer, a SrRuO 3 film layer and a 0.86BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -0.14CaTiO 3 film layer arranged sequentially from bottom to top on the surface of the mica substrate. ;
  • Its manufacturing method includes the following steps:
  • the SrRuO 3 target is used as the laser target through pulsed laser deposition.
  • the target-base distance is 70mm
  • the laser energy is 330mJ
  • the laser wavelength is 248nm
  • the heating temperature of the flexible substrate is 600°C
  • the deposition atmosphere is 70-90mTorr oxygen
  • the deposition time is 8 minutes
  • a SrRuO 3 film layer with a thickness of 50nm is deposited and grown on the surface of the CoFe 2 O 4 film layer to prepare mica/ CoFe 2 O 4 /SrRuO 3 composite film;
  • the mica/CoFe 2 O 4 /SrRuO 3 composite film spin-coated with the precursor solution is heated to 120°C within 5 minutes, and then kept at 380°C for 10 minutes to perform pre-annealing treatment; then heated to 460°C within 5 minutes. °C, and then kept at 790°C for 17 minutes, and then annealed.
  • the entire pre-annealing treatment and annealing treatment kept flowing high-purity oxygen, and then crystallized on the surface of the SrRuO 3 film layer of the mica/CoFe 2 O 4 /SrRuO 3 composite film.
  • a flexible multiferroic film is obtained by preparing a 0.86BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -0.14CaTiO 3 film layer with a thickness of 70nm.
  • a flexible film including a mica substrate and a CoFe 2 O 4 thin film layer, a SrRuO 3 thin film layer and a 0.6BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -0.4CaTiO 3 thin film layer arranged sequentially from bottom to top on the surface of the mica substrate;
  • Its manufacturing method includes the following steps:
  • the SrRuO 3 target is used as the laser target through pulsed laser deposition.
  • the target-base distance is 70mm
  • the laser energy is 330mJ
  • the laser wavelength is 248nm
  • the heating temperature of the flexible substrate is 600°C
  • the deposition atmosphere is 70-90mTorr oxygen
  • the deposition time is 8 minutes
  • a SrRuO 3 film layer with a thickness of 50nm is deposited and grown on the surface of the CoFe 2 O 4 film layer to prepare mica/ CoFe 2 O 4 /SrRuO 3 composite film;
  • the mica/CoFe 2 O 4 /SRO composite film spin-coated with the precursor solution is heated to 120°C within 5 minutes, and then kept at 380°C for 10 minutes to perform pre-annealing treatment; then heated to 460°C within 5 minutes. , and then kept at 790°C for 17 minutes, and then annealed.
  • the entire pre-annealing treatment and annealing treatment kept flowing high-purity oxygen, and then crystallized on the surface of the SrRuO 3 film layer of the mica/CoFe 2 O 4 /SrRuO 3 composite film.
  • a 0.6BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -0.4CaTiO 3 film layer with a thickness of 60nm is obtained, and a flexible film is obtained.
  • the flexible multiferroic film prepared in Application Example 3 was subjected to X-ray diffraction (XRD) testing, and a flat and smooth mica substrate was taken as a reference sample.
  • XRD X-ray diffraction
  • Figure 1 Referring to Figure 1, it can be seen that CoFe 2 O 4 /SrRuO 3 /(1-x)BiTi 0.1 Fe 0.8 Mg 0.1 O 3 -xCaTiO 3 flexible multiferroic films are epitaxially grown along the BTFM (111) direction with preferential orientation. Other impurity peaks appear, indicating good crystal quality.
  • the flexible multiferroic film prepared in the above Application Example 3 was subjected to a piezoelectric force microscope polarization test.
  • the test results are shown in Figure 2, in which (a) is the morphology after applying a voltage of 8V, and (b) is the amplitude diagram after applying a voltage of 8V, (c) is the phase diagram after applying a voltage of 8V; as can be seen from Figure 2, when the voltage is applied to 8V, the shape of the sample does not change, and the amplitude only changes at the junction of the positive and negative voltages.
  • the domain structure shows a 180° phase flip, indicating that the sample can switch between two polarization states under voltage application and has good ferroelectricity.
  • the flexible multiferroic film prepared in the above Application Example 3 was subjected to polarization domain testing under different magnetic fields, and the ferroelectric domain test was observed by applying a magnetic field.
  • the test results are shown in Figure 3.
  • the picture (e) shows the morphology when an external magnetic field of -5000Oe is applied
  • the picture (f) shows the in-plane phase diagram when an external magnetic field of -5000Oe is applied
  • the picture (g) shows the picture when -5000Oe is applied
  • the picture (h) shows the crystal model diagram when an external magnetic field of -5000Oe is applied. It can be seen that the morphology [image (e)] and out-of-plane phase [image (f)] have not changed, while the in-plane phase [image (g)] in some areas has undergone a 180° flip.
  • Figure 4 shows eight logical storage states of the flexible multiferroic film prepared in Application Example 3, which are 000 (a picture), 001 (b picture), 010 (c picture), 011 (d picture), 100 (e picture), 101 (f picture), 110 (g picture) and 111 (h picture), it can be seen that the flexible multiferroic film prepared by this application can realize eight logical storage states and can be used for flexible multi-state storage devices.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Environmental & Geological Engineering (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Inorganic Insulating Materials (AREA)
  • Semiconductor Memories (AREA)

Abstract

一种多铁薄膜前驱体及其制备方法和制得的柔性多铁薄膜。多铁薄膜前驱体由金属盐、络合剂、溶剂制得，金属盐包括铋盐、铁盐、镁盐、钙盐和钛盐；柔性多铁薄膜包括由下至上依次设置柔性衬底、缓冲层、底电极层和多铁功能层；缓冲层为CoFe 2O 4薄膜层，底电极层为SrRuO 3薄膜层，多铁功能层为(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜层；其中，x＝0.1-0.2。采用多铁薄膜前驱体制得的柔性多铁薄膜能在室温下同时具有良好的铁电性与磁性，且具有线性磁电效应的耦合；能通过调整外加磁场调控柔性多铁薄膜的极化畴状态，实现八种逻辑存储态。

Description

一种多铁薄膜前驱体及其制备方法和制得的柔性多铁薄膜 技术领域
本申请涉及微电子器件领域，更具体地说，它涉及一种多铁薄膜前驱体及其制备方法和制得的柔性多铁薄膜。
背景技术
近年来，柔性电子器件以其优异的柔性和通用性引起了人们的广泛关注，尤其是多态存储器，它是柔性集成电路和系统的重要组成部分，基于多铁性磁电材料的多态存储器件能够在一个存储单元中存储多个信息状态，可以以指数形式增加存储容量，并且具有读写速度快、数据保存时间长、功耗低等优点。
目前基于多铁性磁电材料的多态存储技术中，大部分多铁性磁电单相材料的磁化和铁电极化都很小，而大部分多铁性磁电单相材料只在极低温下才表现出铁电性和磁性的共存，实际应用操作难度较大。而对于多铁性磁电复合材料，虽然磁化和铁电极化较强，但是复合相之间还存在着共烧匹配不稳、界面扩散的问题，制约着多铁性磁电材料的磁电耦合性能。而且，多铁性磁电复合材料中铁电相的压电效应和铁磁相的磁致伸缩效应之间的弹性应变/应力耦合过程中，也难以避免存在着能量损失，也都会制约多铁性磁电材料在柔性多态储存领域的应用。
因此，申请人认为，为实现多铁性磁电材料在柔性多态存储领域的应用推广，研发一种能在室温下同时具有较强磁化、铁电极化和耦合性能的多铁性磁电材料是本领域亟需要解决的技术难题。
发明内容
为了解决多铁性磁电单相薄膜需要在及低温下才表现出铁电性和磁性的共存，而多铁性磁电复合薄膜的复合相存在共烧匹配不稳、界面扩散而导致磁电耦合性能受制约的问题，本申请提供一种多铁薄膜前驱体及其制备方法和制得的柔性多铁薄膜。
第一方面，本申请提供一种多铁薄膜前驱体，采用如下的技术方案：
一种多铁薄膜前驱体，由金属盐、络合剂、溶剂制得，所述金属盐包括离子摩尔比为(0.8-0.9)：(0.64-0.72)：(0.08-0.09)：(0.1-0.2)：(0.19-0.28)的铋盐、铁盐、镁盐、钙盐和钛盐。
通过采用上述种类制备多铁薄膜前驱体，且控制金属盐的种类及离子摩尔比，在络合剂的作用下络合反应生成(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3多铁薄膜前驱体，应用于柔性 薄膜的制备中，能形成均匀且稳定的多铁功能层。其次，采用的上述金属盐中，B位阳离子的Ti、Mg等元素的掺杂能稳定Bi基钙钛矿的结构，使得(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3多铁功能层固溶体在准同型相界附近具有强铁电极化和室温弱铁磁性,即具有室温多铁性，并增强了其磁性以及磁电耦合效应。
优选的，所述金属盐由离子摩尔比为(0.8-0.9)：(0.64-0.72)：(0.08-0.09)：(0.1-0.2)：(0.19-0.28)的铋盐、铁盐、镁盐、钙盐和钛盐组成。
优选的，所述多铁薄膜前驱体的摩尔浓度为0.1-0.4moL/L；所述络合剂的添加量为金属盐的23-25％。
通过控制金属盐的组成、前驱体溶液的浓度以及络合剂的添加量，能使金属盐之间络合形成稳定的(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3多铁薄膜前驱体，在应用至制备柔性薄膜过程中，能在底电极层表面均匀旋涂，经过预退火处理及退火处理后形成稳定的多铁功能层，能在室温下表现出铁电性和磁性。
优选的，所述溶剂为乙二醇甲醚，所述络合剂为柠檬酸；所述铋盐为五水合硝酸铋，所述铁盐为九水合硝酸铁，所述镁盐为六水合硝酸镁，所述钙盐为一水合乙酸钙，所述钛盐为钛酸四丁酯。
通过采用上述的溶剂、络合剂以及金属盐，能促进金属盐络合形成稳定的多铁薄膜前驱体体系，便于在制备柔性薄膜过程中，能均匀涂布在底电极层的表面，形成室温下同时具有优良铁电性与磁性的多铁薄膜，且具有线性磁电效应的耦合。
第二方面，本申请提供一种多铁薄膜前驱体的制备方法，采用如下的技术方案：
将铋盐、铁盐、镁盐、钙盐、钛盐加入至溶剂中，搅拌、充分溶解；然后加入络合剂进行络合反应，搅拌均匀后静置2-3天，制得前驱体溶液。
通过采用溶剂将金属盐溶剂后，再加入络合剂促进金属络合生成(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3多铁薄膜前驱体，质量稳定，且易于涂布制备稳定的柔性薄膜。
第三方面，本申请提供一种柔性多铁薄膜，采用如下的技术方案：
一种柔性多铁薄膜，包括柔性衬底以及在所述柔性衬底表面由下至上依次设置的缓冲层、底电极层和多铁功能层；所述柔性衬底为云母衬底，所述缓冲层为CoFe 2O 4薄膜层，所述底电极层为SrRuO 3薄膜层，所述多铁功能层为(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜层，该(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜层是由上述的多铁薄膜前驱体制得，或是由上述制备方法所得的多铁薄膜前驱体制得，其中，x＝0.1-0.2。
采用的云母衬底具有优良的柔性和热稳定性，使制得的多铁薄膜柔性优良，且云母 衬底的热稳定性，能在制备CoFe 2O 4薄膜、SrRuO 3薄膜、(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜过程中，云母衬底不易受热而导致质量受损。而在云母衬底上依次设置CoFe 2O 4薄膜、SrRuO 3薄膜、(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜，(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜可以与CoFe 2O 4薄膜、SrRuO 3薄膜实现外延生长，晶格匹配度好、成膜质量高，能制得的柔性多铁薄膜能在室温下不仅同时具有良好的铁电性与磁性，且具有线性磁电效应的耦合；并能通过调整外加磁场调控柔性多铁薄膜的极化畴状态，实现八种逻辑存储态(000、001、010、011、100、101、110和111)。
优选的，所述缓冲层的厚度为10-20nm，所述底电极层的厚度为25-50nm，所述多铁功能层的厚度为30-80nm。
通过控制缓冲层的厚度、底电极层的厚度以及多铁功能层的厚度，能使制得的柔性多铁薄膜厚度较薄，柔性好，在室温下不仅同时具有优良的铁电性与磁性，而且具有线性磁电效应的耦合。
第四方面，本申请提供一种柔性多铁薄膜的制造方法，采用如下的技术方案：
一种柔性多铁薄膜的制造方法，包括如下步骤：
(1)取云母衬底作为柔性衬底；
(2)在柔性衬底的表面制备CoFe 2O 4薄膜作为缓冲层，制得云母/CoFe 2O 4复合薄膜；
(3)在云母/CoFe 2O 4复合薄膜的缓冲层表面制备SrRuO 3薄膜作为底电极层，制得云母/CoFe 2O 4/SrRuO 3复合薄膜；
(4)将前驱体溶液旋涂至云母/CoFe 2O 4/SrRuO 3复合薄膜的底电极层表面，旋涂均匀后进行预退火处理以及退火处理，制得云母/CoFe 2O 4/SrRuO 3/(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3柔性多铁薄膜。
本申请CoFe 2O 4薄膜的制备、SrRuO 3薄膜的制备，均优选采用脉冲激光沉积工艺进行制备，脉冲激光沉积工艺是指使用脉冲激光器产生的高功率脉冲激光烧蚀所需材料制成的靶材表面，产生高温高压的等离子体，等离子体在沉积气氛中向衬底表面膨胀发射，并在衬底上沉积而形成薄膜。通过采用脉冲激光沉积工艺制备CoFe 2O 4薄膜、SrRuO 3薄膜，能使CoFe 2O 4薄膜在柔性衬底表面稳定沉积成型，能使SrRuO 3薄膜在CoFe 2O 4薄膜表面稳定沉积成型；而且，SrRuO 3薄膜的导电性能好，结构稳定，使得能在SrRuO 3薄膜表面采用旋涂及退火处理来直接外延生长(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜，而且，SrRuO 3薄膜和(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜都是钙钛矿结构，具有相近的晶格参数，使得(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜与CoFe 2O 4薄膜、SrRuO 3薄膜实现外延生长，晶格匹配度 好、成膜质量高，解决目前多铁性磁电复合薄膜的复合相存在共烧匹配不稳、界面扩散而导致磁电耦合性能受制约的问题。
而(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜的制备，则将预先制备好的(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3多铁薄膜前驱体，采用旋涂的方式直接将(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3多铁薄膜前驱体旋涂至SrRuO 3薄膜的表面，结合预退火处理及退火处理，降低(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜内部的缺陷，提高(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜与SrRuO 3薄膜的层间结合性。优选的，所述步骤(2)中，具体采用脉冲激光沉积方式制备CoFe 2O 4薄膜，以CoFe 2O 4靶材作为激光靶材，靶基距为65-75mm，激光能量为300-350mJ，激光波长为230-250nm，柔性衬底的加热温度为580-620℃，沉积气氛为25-55mTorr氧气，沉积时间为4-7min。
通过控制上述CoFe 2O 4薄膜的脉冲激光沉积制备过程的激光条件参数、沉积条件参数，能在柔性衬底表面稳定生成CoFe 2O 4薄膜，且CoFe 2O 4薄膜与柔性衬底表面结合稳定。
优选的，所述步骤(3)中，具体采用脉冲激光沉积方式制备SrRuO 3薄膜，以SrRuO 3靶材作为激光靶材，靶基距为65-75mm，激光能量为300-350mJ，激光波长为230-250nm，柔性衬底的加热温度为585-615℃，沉积气氛为70-90mTorr氧气，沉积时间为5-10min。
通过控制上述SrRuO 3薄膜的脉冲激光沉积制备过程的激光条件参数、沉积条件参数，能在柔性衬底表面稳定生成SrRuO 3薄膜，且SrRuO 3薄膜与CoFe 2O 4薄膜表面结合稳定。
优选的，所述步骤(4)中，在云母/CFO/SRO复合薄膜的底电极层表面旋涂前驱体溶液的操作，具体是先在转速为550-650rpm条件下旋涂6-10s，然后在转速为3800-4200rpm条件下旋涂35-45s。
通过采用先低速旋涂、后高速旋涂的方式，并控制低速旋涂及高速旋涂的转速和时间，能在云母/CoFe 2O 4/SrRuO 3复合薄膜的底电极层表面均匀旋涂多铁薄膜前驱体。具体地，本申请的(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3多铁功能层是在脉冲激光沉积生成的SrRuO 3薄膜表面涂布多铁薄前驱体后经退火制得，SrRuO 3薄膜是由脉冲激光沉积生成的，其表面相比于干净基片表面的表面起伏度更大，使得(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3多铁薄膜前驱体均匀旋涂的难度也相应较大。因而先采用低速旋涂的方式，控制旋涂转速和时间，能将前驱体溶液充分旋涂于SrRuO 3薄膜表面的起伏微结构中，提高SrRuO 3薄膜与(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜的结合性，减少由于前驱体溶液未有充分旋涂于SrRuO 3薄 膜表面的起伏微结构中而导致SrRuO 3薄膜与B(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜之间容易分层；再而采用高速旋涂的方式，控制旋涂转速和时间，能将(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3多铁薄膜前驱体均匀涂覆，能沿着SrRuO 3薄膜的晶格外延外延生长，使制得的柔性多铁薄膜表面平整。
具体操作是先将云母/CoFe 2O 4/SrRuO 3复合薄膜稳定放置于匀胶机吸盘上，然后将(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3多铁薄膜前驱体滴加至云母/CoFe 2O 4/SrRuO 3复合薄膜的底电极层表面，低速旋涂的转速以及高速旋涂的转速，均为设置的匀胶机的转动转速。
优选的，所述步骤(4)中，预退火处理的操作，具体是将先在4-7min内加热升温至120-150℃，然后在360-400℃下保温8-12min。
优选的，所述步骤(4)中，退火处理的操作，具体是将先在4-7min内加热升温至430-480℃，然后在790-810℃下保温13-17min。
通过采用先较低温预退火、后较高温退火，能使(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3多铁薄膜前驱体充分结晶形成(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜，且与SrRuO 3薄膜的结合性好，制得的(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜能与SrRuO 3薄膜、CoFe 2O 4薄膜实现外延生长，晶格匹配度好，成膜质量高。
若采用直接高温退火，则容易使得前驱体未充分结晶完全，另外，亦会使得(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜表面过度退火，存有内部缺陷，导致(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜与SrRuO 3薄膜的结合性较低。另外，本申请的预退火处理以及退火处理过程均保持流动的高纯氧气通入，具体是浓度大于99.999％的高纯氧。
综上所述，本申请具有以下有益效果：
1、本申请的多铁薄膜前驱体，应用于柔性薄膜的制备中，能形成均匀且稳定的多铁功能层，且能使多铁功能层具有强铁电极化和室温弱铁磁性,即具有室温多铁性，并增强了其磁性以及磁电耦合效应。
2、本申请采用的云母衬底具有优良的柔性和热稳定性，能在云母衬底表面依次设置CoFe 2O 4薄膜、SrRuO 3薄膜、(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜，能制得的柔性多铁薄膜能在室温下不仅同时具有良好的铁电性与磁性，且具有线性磁电效应的耦合；并能通过调整外加磁场调控柔性多铁薄膜的极化畴状态，实现八种逻辑存储态(000、001、010、011、100、101、110和111)。
3、本申请中优选采用脉冲激光沉积工艺进行制备CoFe 2O 4薄膜、SrRuO 3薄膜，能使CoFe 2O 4薄膜在柔性衬底表面稳定沉积成型，能使SrRuO 3薄膜在CoFe 2O 4薄膜表面稳定沉 积成型；而且，SrRuO 3薄膜的导电性能好，结构稳定，使得能在SrRuO 3薄膜表面采用旋涂及退火处理来直接外延生长(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜，亦能使得(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜与CoFe 2O 4薄膜、SrRuO 3薄膜实现外延生长，晶格匹配度好、成膜质量高。
4、本申请(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜的制备，采用旋涂的方式直接将(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3前驱体溶液旋涂至SrRuO 3薄膜的表面，结合预退火处理及退火处理，降低(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜内部的缺陷，提高(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜与SrRuO 3薄膜的层间结合性。
附图说明
图1是本申请应用例3制得的柔性多铁薄膜的X射线衍射(XRD)谱图；
图2是本申请应用例3制得的柔性多铁薄膜的压电力显微镜测试结果图；其中，(a)图是施加8V电压后的形貌图，(b)图是施加8V电压后的振幅图，(c)是施加8V电压后相位图；
图3是本申请应用例3制得的柔性多铁薄膜在不同磁场下的极化畴测试结果图；
图4是本申请应用例3制得的柔性多铁薄膜的八种逻辑储存态示意图。
具体实施方式
以下结合附图和实施例对本申请作进一步详细说明。
前驱体溶液的实施例
实施例1
将14.7006g五水合硝酸铋、8.8597g九水合硝酸铁、0.6993g六水合硝酸镁、0.5339g一水合乙酸钙、1.9594g钛酸四丁酯溶解于100mL乙二醇甲醚中，搅拌，使上述组分充分溶解；再加入6.3359g柠檬酸缓进行络合反应，搅拌均匀后静置2天，得到均一稳定透明的0.9BiTi 0.1Fe 0.8Mg 0.1O 3-0.1CaTiO 3前驱体溶液。
实施例2
将13.0672g五水合硝酸铋、7.8754g九水合硝酸铁、0.6216g六水合硝酸镁、1.0678g一水合乙酸钙、2.8876g钛酸四丁酯溶解于100mL乙二醇甲醚中，搅拌，使上述组分充分溶解；再加入6.3359g柠檬酸缓进行络合反应，搅拌均匀后静置3天，得到均一稳定透明的0.8BiTi 0.1Fe 0.8Mg 0.1O 3-0.2CaTiO 3前驱体溶液。
实施例3
将14.0472g五水合硝酸铋、8.4660g九水合硝酸铁、0.6682g六水合硝酸镁、0.7474g一水合 乙酸钙、2.3307g钛酸四丁酯溶解于100mL乙二醇甲醚中，搅拌，使上述组分充分溶解；再加入6.3359g柠檬酸缓进行络合反应，搅拌均匀后静置2天，得到均一稳定透明的0.84BiTi 0.1Fe 0.8Mg 0.1O 3-0.14CaTiO 3前驱体溶液。
实施对比例1
将9.8004g五水合硝酸铋、5.9065g九水合硝酸铁、0.4662g六水合硝酸镁、2.1355g一水合乙酸钙、4.7439g钛酸四丁酯溶解于100mL乙二醇甲醚中，搅拌，使上述组分充分溶解；再加入6.3359g柠檬酸缓进行络合反应，搅拌均匀后静置2天，得到均一稳定透明的0.6BiTi 0.1Fe 0.8Mg 0.1O 3-0.4CaTiO 3前驱体溶液。
应用例
应用例1
一种柔性多铁薄膜，包括云母衬底以及在云母衬底表面由下至上依次设置的CoFe 2O 4薄膜层、SrRuO 3薄膜层和0.9BiTi 0.1Fe 0.8Mg 0.1O 3-0.1CaTiO 3薄膜层；
其制造方法包括如下步骤：
(1)取光滑平整的云母衬底作为柔性衬底；
(2)在柔性衬底的表面通过脉冲激光沉积方式，以CoFe 2O 4靶材作为激光靶材，控制靶基距70mm，激光能量为330mJ，激光波长为248nm，柔性衬底的加热温度为600℃，沉积气氛为50mTorr氧气，沉积时间为5min，在云母衬底上沉积生长制备厚度为15nm的CoFe 2O 4薄膜层，制得云母/CoFe 2O 4复合薄膜；
(3)在云母/CoFe 2O 4复合薄膜的CoFe 2O 4薄膜层表面，通过脉冲激光沉积方式，以SrRuO 3靶材作为激光靶材，靶基距为70mm，激光能量为330mJ，激光波长为248nm，柔性衬底的加热温度为600℃，沉积气氛为80mTorr氧气，沉积时间为7min，在CoFe 2O 4薄膜层表面沉积生长制备厚度为46nm的SrRuO 3薄膜层，制得云母/CoFe 2O 4/SrRuO 3复合薄膜；
(4)将云母/CoFe 2O 4/SrRuO 3复合薄膜稳定放置于匀胶机吸盘上，然后将实施例1制得的前驱体溶液滴加至云母/CoFe 2O 4/SrRuO 3复合薄膜的SrRuO 3薄膜层表面，然后先在转速为600rpm条件下旋涂8s，再在转速为4000rpm条件下旋涂40s；
再将旋涂有前驱体溶液的云母/CoFe 2O 4/SrRuO 3复合薄膜在5min内加热升温至120℃，然后在380℃下保温10min，进行预退火处理；再在5min内加热升温至450℃，然后在800℃下保温15min，进行退火处理，整个预退火处理以及退火处理保持流动的高纯氧气通入，则在云母/CoFe 2O 4/SrRuO 3复合薄膜的SrRuO 3薄膜层表面结晶制得厚度为46nm的 0.9BiTi 0.1Fe 0.8Mg 0.1O 3-0.1CaTiO 3薄膜层，则制得柔性多铁薄膜。
应用例2
一种柔性多铁薄膜，包括云母衬底以及在云母衬底表面由下至上依次设置的CoFe 2O 4薄膜层、SrRuO 3薄膜层和0.8BiTi 0.1Fe 0.8Mg 0.1O 3-0.2CaTiO 3薄膜层；
其制造方法包括如下步骤：
(1)取光滑平整的云母衬底作为柔性衬底；
(2)在柔性衬底的表面通过脉冲激光沉积方式，以CoFe 2O 4靶材作为激光靶材，控制靶基距为65mm，激光能量为330mJ，激光波长为248nm，柔性衬底的加热温度为610℃，沉积气氛为50mTorr氧气，沉积时间为4min，在云母衬底上沉积生长制备厚度为10nm的CoFe 2O 4薄膜层，制得云母/CoFe 2O 4复合薄膜；
(3)在云母/CoFe 2O 4复合薄膜的CoFe 2O 4薄膜层表面，通过脉冲激光沉积方式，以SrRuO 3靶材作为激光靶材，靶基距为65mm，激光能量为330mJ，激光波长为248nm，柔性衬底的加热温度为600℃，沉积气氛为80mTorr氧气，沉积时间为6min，在CoFe 2O 4薄膜层表面沉积生长制备厚度为30nm的SrRuO 3薄膜层，制得云母/CoFe 2O 4/SrRuO 3复合薄膜；
(4)将云母/CoFe 2O 4/SrRuO 3复合薄膜稳定放置于匀胶机吸盘上，然后将实施例2制得的前驱体溶液滴加至云母/CoFe 2O 4/SrRuO 3复合薄膜的SrRuO 3薄膜层表面，然后先在转速为650rpm条件下旋涂8s，再在转速为4200rpm条件下旋涂40s；
再将旋涂有前驱体溶液的云母/CoFe 2O 4/SrRuO 3复合薄膜在5min内加热升温至120℃，然后在380℃下保温10min，进行预退火处理；再在5min内加热升温至450℃，然后在810℃下保温15min，进行退火处理，整个预退火处理以及退火处理保持流动的高纯氧气通入，则在云母/CoFe 2O 4/SrRuO 3复合薄膜的SrRuO 3薄膜层表面结晶制得厚度为40nm的0.8BiTi 0.1Fe 0.8Mg 0.1O 3-0.2CaTiO 3薄膜层，则制得柔性多铁薄膜。
应用例3
一种柔性多铁薄膜，包括云母衬底以及在云母衬底表面由下至上依次设置的CoFe 2O 4薄膜层、SrRuO 3薄膜层和0.86BiTi 0.1Fe 0.8Mg 0.1O 3-0.14CaTiO 3薄膜层；
其制造方法包括如下步骤：
(1)取光滑平整的云母衬底作为柔性衬底；
(2)在柔性衬底的表面通过脉冲激光沉积方式，以CoFe 2O 4靶材作为激光靶材，控制靶基距为70mm，激光能量为330mJ，激光波长为248nm，柔性衬底的加热温度为600℃，沉积气氛为50mTorr氧气，沉积时间为8min，在云母衬底上沉积生长制备厚度为20nm的 CoFe 2O 4薄膜层，制得云母/CoFe 2O 4复合薄膜；
(3)在云母/CoFe 2O 4复合薄膜的CoFe 2O 4薄膜层表面，通过脉冲激光沉积方式，以SrRuO 3靶材作为激光靶材，靶基距为70mm，激光能量为330mJ，激光波长为248nm，柔性衬底的加热温度为600℃，沉积气氛为70-90mTorr氧气，沉积时间为8min，在CoFe 2O 4薄膜层表面沉积生长制备厚度为50nm的SrRuO 3薄膜层，制得云母/CoFe 2O 4/SrRuO 3复合薄膜；
(4)将云母/CoFe 2O 4/SrRuO 3复合薄膜稳定放置于匀胶机吸盘上，然后将实施例3制得的前驱体溶液滴加至云母/CFO/SRO复合薄膜的SrRuO 3薄膜层表面，然后先在转速为600rpm条件下旋涂8s，再在转速为4000rpm条件下旋涂40s；
再将旋涂有前驱体溶液的云母/CoFe 2O 4/SrRuO 3复合薄膜在5min内加热升温至120℃，然后在380℃下保温10min，进行预退火处理；再在5min内加热升温至460℃，然后在790℃下保温17min，进行退火处理，整个预退火处理以及退火处理保持流动的高纯氧气通入，则在云母/CoFe 2O 4/SrRuO 3复合薄膜的SrRuO 3薄膜层表面结晶制得厚度为70nm的0.86BiTi 0.1Fe 0.8Mg 0.1O 3-0.14CaTiO 3薄膜层，则制得柔性多铁薄膜。
应用对比例
应用对比例1
一种柔性薄膜，包括云母衬底以及在云母衬底表面由下至上依次设置的CoFe 2O 4薄膜层、SrRuO 3薄膜层和0.6BiTi 0.1Fe 0.8Mg 0.1O 3-0.4CaTiO 3薄膜层；
其制造方法包括如下步骤：
(1)取光滑平整的云母衬底作为柔性衬底；
(2)在柔性衬底的表面通过脉冲激光沉积方式，以CoFe 2O 4靶材作为激光靶材，控制靶基距为70mm，激光能量为330mJ，激光波长为248nm，柔性衬底的加热温度为600℃，沉积气氛为50mTorr氧气，沉积时间为8min，在云母衬底上沉积生长制备厚度为15nm的CoFe 2O 4薄膜层，制得云母/CoFe 2O 4复合薄膜；
(3)在云母/CoFe 2O 4复合薄膜的CoFe 2O 4薄膜层表面，通过脉冲激光沉积方式，以SrRuO 3靶材作为激光靶材，靶基距为70mm，激光能量为330mJ，激光波长为248nm，柔性衬底的加热温度为600℃，沉积气氛为70-90mTorr氧气，沉积时间为8min，在CoFe 2O 4薄膜层表面沉积生长制备厚度为50nm的SrRuO 3薄膜层，制得云母/CoFe 2O 4/SrRuO 3复合薄膜；
(4)将云母/CoFe 2O 4/SrRuO 3复合薄膜稳定放置于匀胶机吸盘上，然后将实施对比例1制得的前驱体溶液滴加至云母/CoFe 2O 4/SrRuO 3复合薄膜的SrRuO 3薄膜层表面，然后先在转速为 600rpm条件下旋涂8s，再在转速为4000rpm条件下旋涂40s；
再将旋涂有前驱体溶液的云母/CoFe 2O 4/SRO复合薄膜在5min内加热升温至120℃，然后在380℃下保温10min，进行预退火处理；再在5min内加热升温至460℃，然后在790℃下保温17min，进行退火处理，整个预退火处理以及退火处理保持流动的高纯氧气通入，则在云母/CoFe 2O 4/SrRuO 3复合薄膜的SrRuO 3薄膜层表面结晶制得厚度为60nm的0.6BiTi 0.1Fe 0.8Mg 0.1O 3-0.4CaTiO 3薄膜层，则制得柔性薄膜。
性能检测试验
(一)柔性多铁薄膜的X射线衍射(XRD)测试
对上述应用例3所制得的柔性多铁薄膜进行X射线衍射(XRD)测试，并取一平整光滑的云母衬底作为参照样，测试结果如附图1所示。参照附图1，可见CoFe 2O 4/SrRuO 3/(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3柔性多铁薄膜都是沿着BTFM(111)方向择优取向外延生长的，没有其他杂峰出现，结晶质量好。
(二)柔性多铁薄膜的压电力显微镜极化测试
对上述应用例3所制得的柔性多铁薄膜进行压电力显微镜极化测试，测试结果如附图2所示，其中，(a)图是施加8V电压后的形貌图，(b)图是施加8V电压后的振幅图，(c)是施加8V电压后相位图；从附图2可以看出，当电压施加8V时样品形貌没有变化，振幅只在正负电压交界处出现变化，而畴结构出现180°相位翻转，说明样品在电压施加下能够实现两种极化态的切换，具有良好的铁电性。
(三)柔性多铁薄膜的极化畴测试
对上述应用例3所制得的柔性多铁薄膜进行不同磁场下的极化畴测试，通过施加磁场观察铁电畴测试，测试结果如附图3所示，附图3中，其中，(a)图为未施加磁场时的形貌图，(b)图为面内相位图，(c)图为面外相位图，(d)图为晶体模型图。
当施加-5000Oe的外加磁场时，(e)图为施加-5000Oe外加磁场时的形貌图，(f)图为施加-5000Oe外加磁场时的面内相位图，(g)图为施加-5000Oe外加磁场时的面外相位图，(h)图为施加-5000Oe外加磁场时的晶体模型图。可以看出形貌[(e)图]和面外相位[(f)图]没有发生变化，而部分区域的面内相位[图(g)]发生了180°翻转。
当再次施加反向+5000Oe的外加磁场时，(i)图为施加+5000Oe外加磁场时的形貌图，(j)图为施加+5000Oe外加磁场时的面内相位图，(k)图为施加+5000Oe外加磁场时的面外相位图，(l)图为施加+5000Oe外加磁场时的晶体模型图。可以看出形貌[(i)图] 和面外相位[(j)图]没有发生变化，而部分区域的面内相位[(k)图]恢复到初始状态；说明当面外极化方向为单一向上时，磁场方向的改变会使样品存在两种状态，且表明磁场施加下能存在两种状态的切换，具有良好的铁磁性。
(四)柔性多铁薄膜的逻辑状态
附图4中呈现了应用例3所制得的柔性多铁薄膜的八种逻辑储存态，分别为000(a图)、001(b图)、010(c图)、011(d图)、100(e图)、101(f图)、110(g图)和111(h图)，可见本申请制得的柔性多铁薄膜可实现八种逻辑储存态，可用于柔性多态储存器件。
而应用对比例1制得的0.6BiTi 0.1Fe 0.8Mg 0.1O 3-0.4CaTiO 3柔性薄膜无法在室温下实现磁电耦合。
本具体实施例仅仅是对本申请的解释，其并不是对本申请的限制，本领域技术人员在阅读完本说明书后可以根据需要对本实施例做出没有创造性贡献的修改，但只要在本申请的权利要求范围内都受到专利法的保护。

Claims (11)

  1. 一种多铁薄膜前驱体，其特征在于：该多铁薄膜前驱体由金属盐、络合剂、溶剂制得，所述金属盐包括离子摩尔比为(0.8-0.9)：(0.64-0.72)：(0.08-0.09)：(0.1-0.2)：(0.19-0.28)的铋盐、铁盐、镁盐、钙盐和钛盐。
  2. 根据权利要求1所述的多铁薄膜前驱体，其特征在于：所述金属盐由离子摩尔比为(0.8-0.9)：(0.64-0.72)：(0.08-0.09)：(0.1-0.2)：(0.19-0.28)的铋盐、铁盐、镁盐、钙盐和钛盐组成。
  3. 根据权利要求1所述的多铁薄膜前驱体，其特征在于：所述多铁薄膜前驱体的摩尔浓度为0.1-0.4moL/L；所述络合剂的添加量为金属盐的23-25％。
  4. 根据权利要求1-3任一项所述的多铁薄膜前驱体，其特征在于：所述溶剂为乙二醇甲醚，所述络合剂为柠檬酸；所述铋盐为五水合硝酸铋，所述铁盐为九水合硝酸铁，所述镁盐为六水合硝酸镁，所述钙盐为一水合乙酸钙，所述钛盐为钛酸四丁酯。
  5. 一种如权利要求1-4任一项所述多铁薄膜前驱体的制备方法，其特征在于：将铋盐、铁盐、镁盐、钙盐、钛盐加入至溶剂中，搅拌、充分溶解；然后加入络合剂进行络合反应，搅拌均匀后静置2-3天，制得多铁薄膜前驱体。
  6. 一种柔性多铁薄膜，其特征在于：包括柔性衬底以及在所述柔性衬底表面由下至上依次设置的缓冲层、底电极层和多铁功能层；所述柔性衬底为云母衬底，所述缓冲层为CoFe 2O 4薄膜层，所述底电极层为SrRuO 3薄膜层，所述多铁功能层为(1-x) BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3薄膜层，由权利要求1-4任一项的多铁薄膜前驱体制得，或是由权利要求5的制备方法所得的多铁薄膜前驱体制得，其中，x＝0.1-0.2。
  7. 根据权利要求6所述的柔性多铁薄膜，其特征在于：所述缓冲层的厚度为10-20nm，所述底电极层的厚度为25-50nm，所述多铁功能层的厚度为30-80nm。
  8. 一种如权利要求6或7所述的柔性多铁薄膜的制造方法，其特征在于：包括如下步骤：
    (1)取云母衬底作为柔性衬底；
    (2)在柔性衬底的表面制备CoFe 2O 4薄膜作为缓冲层，制得云母/CoFe 2O 4复合薄膜；
    (3)在云母/CoFe 2O 4复合薄膜的缓冲层表面制备SrRuO 3薄膜作为底电极层，制得云母/CoFe 2O 4/SrRuO 3复合薄膜；
    (4)将多铁薄膜前驱体旋涂至云母/CoFe 2O 4/SrRuO 3复合薄膜的底电极层表面，旋涂均匀后进行预退火处理以及退火处理，制得云母/CoFe 2O 4/SrRuO 3/(1-x)BiTi 0.1Fe 0.8Mg 0.1O 3-xCaTiO 3柔性多铁薄膜。
  9. 根据权利要求8所述的一种柔性多铁薄膜的制造方法，其特征在于：所述步骤(2)中，具体采用脉冲激光沉积方式制备CoFe 2O 4薄膜，以CoFe 2O 4靶材作为激光靶材，靶基距为65-75mm，激光能量为300-350mJ，激光波长为230-250nm，柔性衬底的加热温度为580-620℃，沉积气氛为25-55mTorr氧气，沉积时间为4-7min。
  10. 根据权利要求8所述的一种柔性多铁薄膜的制造方法，其特 征在于：所述步骤(3)中，具体采用脉冲激光沉积方式制备SrRuO 3薄膜，以SrRuO 3靶材作为激光靶材，靶基距为65-75mm，激光能量为300-350mJ，激光波长为230-250nm，柔性衬底的加热温度为585-615℃，沉积气氛为70-90mTorr氧气，沉积时间为5-10min。
  11. 根据权利要求8所述的一种柔性多铁薄膜的制造方法，其特征在于：所述步骤(4)中，在云母/CoFe 2O 4/SrRuO 3复合薄膜的底电极层表面旋涂前驱体溶液的操作，具体是先在转速为550-650rpm条件下旋涂6-10s，然后在转速为3800-4200rpm条件下旋涂35-45s；
    所述步骤(4)中，预退火处理的操作，具体是将先在4-7min内加热升温至120-150℃，然后在360-400℃下保温8-12min；
    所述步骤(4)中，退火处理的操作，具体是将先在4-7min内加热升温至430-480℃，然后在790-810℃下保温13-17min。
PCT/CN2022/109488 2022-07-19 2022-08-01 一种多铁薄膜前驱体及其制备方法和制得的柔性多铁薄膜 WO2024016379A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202210855370.8A CN115231619A (zh) 2022-07-19 2022-07-19 一种多铁薄膜前驱体及其制备方法和制得的柔性多铁薄膜
CN202210855370.8 2022-07-19

Publications (1)

Publication Number Publication Date
WO2024016379A1 true WO2024016379A1 (zh) 2024-01-25

Family

ID=83674024

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2022/109488 WO2024016379A1 (zh) 2022-07-19 2022-08-01 一种多铁薄膜前驱体及其制备方法和制得的柔性多铁薄膜

Country Status (2)

Country Link
CN (1) CN115231619A (zh)
WO (1) WO2024016379A1 (zh)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101376600A (zh) * 2008-09-26 2009-03-04 清华大学 一种利用导电氧化物作为缓冲层的叠层铁电/磁性多铁性磁电复合薄膜及其制备方法
WO2012094266A1 (en) * 2011-01-06 2012-07-12 Los Alamos National Security, Llc Multiferroics that are both ferroelectric and ferromagnetic at room temperature
CN108597875A (zh) * 2018-04-03 2018-09-28 湘潭大学 一种透明柔性全氧化物异质外延铁电薄膜及其制备方法
CN108911730A (zh) * 2018-07-12 2018-11-30 深圳先进技术研究院 B位掺杂铋铁氧体固溶体薄膜及其制备方法和应用
CN113248248A (zh) * 2020-08-13 2021-08-13 深圳先进技术研究院 固溶体多铁薄膜、制备方法及应用于5g存储技术的电子器件

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101527314B (zh) * 2009-03-19 2011-04-13 电子科技大学 ABO3/MgO/GaN异质结构制备方法
CN102751094B (zh) * 2011-04-22 2015-08-05 华进半导体封装先导技术研发中心有限公司 一种基于欧姆接触的铁电薄膜电容及其制备方法
US9680085B2 (en) * 2014-03-07 2017-06-13 Canon Kabushiki Kaisha Ceramic powder, piezoelectric ceramic, piezoelectric element, and electronic equipment
CN114665003A (zh) * 2022-03-23 2022-06-24 湘潭大学 一种含缺陷偶极子的柔性铁电薄膜及制作方法

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101376600A (zh) * 2008-09-26 2009-03-04 清华大学 一种利用导电氧化物作为缓冲层的叠层铁电/磁性多铁性磁电复合薄膜及其制备方法
WO2012094266A1 (en) * 2011-01-06 2012-07-12 Los Alamos National Security, Llc Multiferroics that are both ferroelectric and ferromagnetic at room temperature
CN108597875A (zh) * 2018-04-03 2018-09-28 湘潭大学 一种透明柔性全氧化物异质外延铁电薄膜及其制备方法
CN108911730A (zh) * 2018-07-12 2018-11-30 深圳先进技术研究院 B位掺杂铋铁氧体固溶体薄膜及其制备方法和应用
CN113248248A (zh) * 2020-08-13 2021-08-13 深圳先进技术研究院 固溶体多铁薄膜、制备方法及应用于5g存储技术的电子器件

Also Published As

Publication number Publication date
CN115231619A (zh) 2022-10-25

Similar Documents

Publication Publication Date Title
US8124254B2 (en) Heterostructure of ferromagnetic and ferroelectric materials with magneto-optic and electro-optic effects
TW440959B (en) Low imprint ferroelectric material for long retention memory and method of making the same
CN102051582B (zh) 一种在Si衬底上制备高（100）取向BiFeO3薄膜的方法
WO2021143187A1 (zh) 非对称的铁电功能层阵列、铁电隧道结多值存储单元的制备方法
JP2008509509A5 (zh)
WO2021253527A1 (zh) 一种HfO2基铁电电容器及其制备方法和HfO2基铁电存储器
Kossar et al. Ferroelectric polarization induced memristive behavior in bismuth ferrite (BiFeO3) based memory devices
CN101692463B (zh) 一种混合纳米晶存储器的电容结构及其制备方法
CN110635027A (zh) 一种基于MXene电极的半导体器件及其制备方法
Zhang et al. Structural and electrical study of highly (100)-oriented KNN films fabricated by a sol-gel non-alkoxide process
CN102071399B (zh) 全钙钛矿多铁性磁电复合薄膜
Chen et al. Integration of single oriented oxide superlattices on silicon using various template techniques
Gumiel et al. Thin film processing of multiferroic BiFeO3: From sophistication to simplicity. A review
WO2024016379A1 (zh) 一种多铁薄膜前驱体及其制备方法和制得的柔性多铁薄膜
Man et al. Fabrication and polarization-modulated resistive switching behavior of predominantly (110)-oriented BiFeO 3 thin films on indium tin oxide/glass substrates
Liu et al. Structure and electrical properties of Mn doped Bi (Mg1/2Ti1/2) O3-PbTiO3 ferroelectric thin films
Lei et al. The tunable dielectric properties of sputtered yttrium oxide films
Verma et al. Processing Techniques with Heating Conditions for Multiferroic Systems of BiFeO 3, BaTiO 3, PbTiO 3, CaTiO 3 Thin Films
WO2022032584A1 (zh) 固溶体多铁薄膜、制备方法及应用于5g存储技术的电子器件
CN113539654B (zh) 调控并增强lsmo薄膜磁各向异性的方法、磁各向异性可调的lsmo薄膜及其制备方法
Guo et al. Enhancement of multiferroic properties in Bi0. 92Ho0. 08Fe0. 97Mn0. 03O3/Zn0. 5Ni0. 5Fe2O4 bilayered thin films by tunable schottky barrier and interface barrier
CN113363384A (zh) 一种HfO2基铁电隧道结器件及其制备方法
TW200923976A (en) Metal substrate for a superconducting thin-film strip conductor
Lin et al. Excellent ferroelectric properties sensitive to external voltage in PZT/LNO/NSTO heterostructures prepared by a sol-gel method
CN111087024A (zh) 一种掺杂改性铁酸铋薄膜的制备方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22951647

Country of ref document: EP

Kind code of ref document: A1