CN108987560B - Perovskite ferroelectric film with multilevel multi-domain nano structure based on crystallography engineering and preparation method thereof - Google Patents
Perovskite ferroelectric film with multilevel multi-domain nano structure based on crystallography engineering and preparation method thereof Download PDFInfo
- Publication number
- CN108987560B CN108987560B CN201810826422.2A CN201810826422A CN108987560B CN 108987560 B CN108987560 B CN 108987560B CN 201810826422 A CN201810826422 A CN 201810826422A CN 108987560 B CN108987560 B CN 108987560B
- Authority
- CN
- China
- Prior art keywords
- domain
- film
- thin film
- perovskite ferroelectric
- nano structure
- 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.)
- Active
Links
- 239000002086 nanomaterial Substances 0.000 title claims abstract description 58
- 238000002050 diffraction method Methods 0.000 title claims abstract description 7
- 238000002360 preparation method Methods 0.000 title claims description 10
- 238000012407 engineering method Methods 0.000 title description 2
- 239000010408 film Substances 0.000 claims abstract description 77
- 239000010409 thin film Substances 0.000 claims abstract description 77
- 238000000151 deposition Methods 0.000 claims description 35
- 230000005684 electric field Effects 0.000 claims description 31
- 230000008021 deposition Effects 0.000 claims description 25
- 238000004549 pulsed laser deposition Methods 0.000 claims description 20
- 229910004121 SrRuO Inorganic materials 0.000 claims description 17
- 238000000034 method Methods 0.000 claims description 17
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 14
- 229910052760 oxygen Inorganic materials 0.000 claims description 14
- 239000001301 oxygen Substances 0.000 claims description 14
- 238000001816 cooling Methods 0.000 claims description 12
- 229910002370 SrTiO3 Inorganic materials 0.000 claims description 11
- 239000000758 substrate Substances 0.000 claims description 9
- 238000004519 manufacturing process Methods 0.000 claims 3
- 230000010287 polarization Effects 0.000 abstract description 17
- 230000009467 reduction Effects 0.000 abstract description 6
- 230000004044 response Effects 0.000 abstract description 6
- 230000000052 comparative effect Effects 0.000 description 25
- 238000003917 TEM image Methods 0.000 description 12
- 239000000463 material Substances 0.000 description 10
- 229910002353 SrRuO3 Inorganic materials 0.000 description 7
- 125000004122 cyclic group Chemical group 0.000 description 7
- 239000013078 crystal Substances 0.000 description 6
- 238000010586 diagram Methods 0.000 description 6
- 238000009661 fatigue test Methods 0.000 description 4
- 239000000523 sample Substances 0.000 description 4
- 238000012876 topography Methods 0.000 description 3
- 229910002367 SrTiO Inorganic materials 0.000 description 2
- 238000005034 decoration Methods 0.000 description 2
- 238000002524 electron diffraction data Methods 0.000 description 2
- 238000011065 in-situ storage Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000013590 bulk material Substances 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 238000001338 self-assembly Methods 0.000 description 1
- 230000002269 spontaneous effect Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N30/00—Piezoelectric or electrostrictive devices
- H10N30/80—Constructional details
- H10N30/85—Piezoelectric or electrostrictive active materials
- H10N30/853—Ceramic compositions
- H10N30/8548—Lead-based oxides
- H10N30/8554—Lead-zirconium titanate [PZT] based
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N30/00—Piezoelectric or electrostrictive devices
- H10N30/01—Manufacture or treatment
- H10N30/04—Treatments to modify a piezoelectric or electrostrictive property, e.g. polarisation characteristics, vibration characteristics or mode tuning
- H10N30/045—Treatments to modify a piezoelectric or electrostrictive property, e.g. polarisation characteristics, vibration characteristics or mode tuning by polarising
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N30/00—Piezoelectric or electrostrictive devices
- H10N30/01—Manufacture or treatment
- H10N30/09—Forming piezoelectric or electrostrictive materials
- H10N30/093—Forming inorganic materials
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Nanotechnology (AREA)
- Manufacturing & Machinery (AREA)
- Composite Materials (AREA)
- General Physics & Mathematics (AREA)
- Materials Engineering (AREA)
- Crystallography & Structural Chemistry (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Physics & Mathematics (AREA)
- Ceramic Engineering (AREA)
- Inorganic Chemistry (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
- Physical Vapour Deposition (AREA)
- Formation Of Insulating Films (AREA)
Abstract
The invention provides a perovskite ferroelectric thin film with a multi-stage multi-domain nano structure based on crystallography engineering, wherein the multi-stage multi-domain nano structure is composed of a single (a)1,c)/(a2C) a multi-domain band arrangement, wherein the perovskite ferroelectric thin film is (111) oriented Pb (Zr)0.2Ti0.8)O3And (3) epitaxial thin films. The multi-stage multi-domain nano structure in the perovskite ferroelectric thin film provided by the invention is composed of single (a)1,c)/(a2And c) the multi-domain zones are arranged, so that the electrical property of the perovskite ferroelectric film is enhanced, and compared with the perovskite ferroelectric film without the multi-stage multi-domain nano structure, the ferroelectric polarization is enhanced besides the coercive field reduction and the dielectric response enhancement, and the fatigue resistance is greatly improved.
Description
Technical Field
The invention relates to the technical field of ferroelectric materials, in particular to a perovskite ferroelectric film with a multi-level and multi-domain nano structure based on crystallographic engineering and a preparation method thereof.
Background
The ferroelectric material is a material having a ferroelectric effect, in which minute regions having the same spontaneous polarization direction form ferroelectric domains (domains), and the boundary between adjacent ferroelectric domains is a domain wall. In the absence of an applied electric field, the orientation of the domains is arbitrary and the ferroelectric material does not show macroscopic polarization behavior. If an external electric field is applied to the ferroelectric material, the internal domains thereof may be reoriented, and the reoriented domains tend to have a polarization direction as consistent as possible with the direction of the applied electric field. A crystal grain usually includes a plurality of ferroelectric domains of different orientations, and only in the ferroelectric single crystal, the entire crystal is composed of one domain. Since the material may have composition non-uniformity, impurities, interfaces, external constraint conditions and the like, and the free energy of the whole system reaches the minimum value, domain structures with different orientations appear, and the ferroelectric material with the multi-domain structure attracts the attention of a plurality of scientific researchers because of excellent physical properties and wide application prospect.
The engineered domain refers to a domain configuration which is high in stability and difficult to displace and is formed after an electric field is applied to a crystal in a non-polarization direction. Such engineered domains can generally improve the electromechanical properties of the material, including piezoelectric strain without hysteresis and improved dielectric and piezoelectric coefficients. Furthermore, these improvements are inherent due to the thermodynamic stability of the multi-domain structure and are therefore more desirable for device applications. Notably, engineering domains often requires the ability to pre-form three or four equivalent domain variants in the ferroelectric material. Although the geometry of the film is essentially the same as that of the bulk material, there are few reports in the prior art of exploring engineered domains in films. This may be due in part to the particular manner of nanoscale self-assembly of domain variants under two-dimensional mechanical constraints.
Therefore, it is necessary to perform crystallographic design on the nano-domains of the thin film material to improve the electromechanical properties thereof.
Disclosure of Invention
The invention aims to provide a perovskite ferroelectric thin film with a multi-level multi-domain nano structure based on crystallographic engineering and a preparation method thereof1,c)/(a2And c) the multi-domain strips are arranged, so that the coercive field is reduced, the dielectric response is enhanced, the ferroelectric polarization is enhanced, and the fatigue resistance is greatly improved.
In order to achieve the above object, the present invention provides the following technical solutions:
the invention provides a perovskite ferroelectric film with a multi-stage multi-domain nano structure based on crystallography engineering, which is characterized in that the multi-stage multi-domain nano structure is composed of a single (a)1,c)/(a2C) a multi-domain band arrangement, wherein the perovskite ferroelectric thin film is (111) oriented Pb (Zr)0.2Ti0.8)O3And (3) epitaxial thin films.
Preferably, the thickness of the perovskite ferroelectric thin film is more than or equal to 100 nm.
Preferably, the thickness of the perovskite ferroelectric thin film is 200-250 nm.
The invention provides a preparation method of a perovskite ferroelectric film with a multilevel and multidomain nano structure based on crystallographic engineering, which comprises the following steps:
(1) pulsed laser deposition of (111) -oriented SrTiO3Single-sided epitaxial growth of (111) oriented SrRuO on substrates3A thin film bottom electrode;
(2) SrRuO in the step (1) by adopting a pulse laser deposition method3Epitaxially growing (111) -oriented Pb (Zr) on the upper surface of the thin film bottom electrode0.2Ti0.8)O3A film;
(3) adding Pb (Zr) in the step (2)0.2Ti0.8)O3The film is heated at 50-60 ℃ per minute-1Cooling to room temperature at a cooling rate, and applying a circulating external electric field to the Pb (Zr)0.2Ti0.8)O3And forming a multilevel multi-domain nano structure in the film to obtain the perovskite ferroelectric film with the multilevel multi-domain nano structure.
Preferably, the operating conditions of the pulsed laser deposition method in step (1) include: the reaction chamber is vacuumized to be less than or equal to 1 multiplied by 10-6Pa; the deposition temperature is 650-700 ℃; the deposition oxygen pressure is 50-100 mtorr; the laser energy density is 1.7 J.cm-2(ii) a The laser pulse frequency was 10 Hz.
Preferably, the SrRuO3The thickness of the film bottom electrode is 5-25 nm.
Preferably, the operating conditions of the pulsed laser deposition method in step (2) include: the reaction chamber is vacuumized to be less than or equal to 1 multiplied by 10-6Pa; the deposition temperature is 550-600 ℃; the oxygen pressure of the deposit is 100-150 mtorr; the laser energy density is 1.7 J.cm-2(ii) a The laser pulse frequency was 10 Hz.
Preferably, the voltage of the circulating external electric field in the step (3) is +/-5 to +/-8V.
Preferably, the application times of the external electric field in the circulation in the step (3) are 3-7 times.
The invention provides a perovskite ferroelectric thin film with a multi-stage multi-domain nano structure based on crystallography engineering, wherein the multi-stage multi-domain nano structure is composed of a single (a)1,c)/(a2C) a multi-domain band arrangement, wherein the perovskite ferroelectric thin film is (111) oriented Pb (Zr)0.2Ti0.8)O3And (3) epitaxial thin films. The multi-stage multi-domain nano structure in the perovskite ferroelectric thin film provided by the invention is composed of single (a)1,c)/(a2And c) the multi-domain zones are arranged, so that the electrical property of the perovskite ferroelectric film is enhanced, and compared with the perovskite ferroelectric film without the multi-stage multi-domain nano structure, the ferroelectric polarization is enhanced besides the coercive field reduction and the dielectric response enhancement, and the fatigue resistance is greatly improved. The experimental results in the examples show that (111) oriented Pb (Zr) consisting of a single multi-domain band0.2Ti0.8)O3The film has the minimum coercive electric field and the maximum dielectric response; and consisting of a single multi-domain band of (111) -oriented Pb (Zr)0.2Ti0.8)O3The film is compared with (111) oriented Pb (Zr) composed of three multi-domain bands0.2Ti0.8)O3The remanent polarization and the dielectric constant of the film are respectively improved by about 25 percent and 50 percent; further, (111) oriented Pb (Zr) consisting of single multi-domain band0.2Ti0.8)O3The fatigue resistance of the film is better than that of the perovskite ferroelectric film without the multi-stage multi-domain nano structure.
The invention also provides a preparation method of the perovskite ferroelectric film with the multilevel multi-domain nano structure based on the crystallographic engineering, the preparation method provided by the invention is simple to operate, an asymmetric mechanical boundary condition is manufactured in the perovskite ferroelectric film by a rapid cooling method, and then a cyclic external electric field is applied to the perovskite ferroelectric film for polarization, so that a single (a) phase is formed in the perovskite ferroelectric film1,c)/(a2And c) a multi-level multi-domain nano structure formed by arranging multi-domain zones.
Drawings
FIG. 1 is a schematic structural diagram of a multi-level multi-domain nanostructure in a perovskite ferroelectric thin film provided in example 1; wherein, 1, a2A domain; 2. c domain; 3. a is1A domain; 4. a probe for applying a cyclic external electric field;
FIG. 2 is a schematic structural diagram of a multi-level multi-domain nanostructure in a conventional perovskite ferroelectric thin film provided in comparative example 1; wherein, 1, a2A domain; 2. c domain; 3. a is1A domain; 4. a probe for applying a cyclic external electric field;
FIG. 3 is a PFM image of the perovskite ferroelectric thin film of example 1; wherein (c) a topography map; (d) an out-of-plane amplitude map; (e) an in-plane amplitude map;
FIG. 4 is a PFM image of the perovskite ferroelectric thin film in comparative example 1; wherein (f) is a topography; (g) an out-of-plane amplitude map; (h) an in-plane amplitude map;
FIG. 5 is a TEM image of the perovskite ferroelectric thin film in example 1; wherein (a) bright field TEM image of the cross section of the in-situ grown perovskite ferroelectric thin film; (b) bright field TEM image of the cross section of the perovskite ferroelectric thin film after electric polarization; (c) high magnification TEM images of multi-stage multi-domain nanostructures (taken from the area circled in b); (a) the inset in the figure is the selected region electron diffraction pattern of the perovskite ferroelectric thin film; (b) inset in the figure is a dark field TEM image (top left) and an in-plane PFM image within the same region;
FIG. 6 is a graph comparing the hysteresis loops of the perovskite ferroelectric thin films prepared in example 1 and comparative examples 1 to 3;
FIG. 7 is a comparison of butterfly curves for perovskite ferroelectric thin films prepared in example 1 and comparative examples 1 to 3;
fig. 8 is a graph comparing fatigue curves of the perovskite ferroelectric thin films of example 1 and comparative example 1, and the inset is a graph comparing the hysteresis loops (i.e., PE) of the perovskite thin films of example 1 before and after the fatigue test.
Fig. 9 is a graph comparing fatigue curves of the perovskite ferroelectric thin films of comparative examples 2 and 3, and the inset is a graph comparing hysteresis loops (i.e., PE) of the perovskite thin films of comparative examples 2 and 3 before and after the fatigue test.
Detailed Description
The invention provides a perovskite ferroelectric thin film with a multi-stage multi-domain nano structure based on crystallography engineering, wherein the multi-stage multi-domain nano structure is composed of a single (a)1,c)/(a2C) a multi-domain band arrangement, wherein the perovskite ferroelectric thin film is (111) oriented Pb (Zr)0.2Ti0.8)O3And (3) epitaxial thin films. In the invention, the thickness of the perovskite ferroelectric thin film is preferably not less than 100nm, and more preferably 200-250 nm.
The invention provides a preparation method of a perovskite ferroelectric film with a multilevel and multidomain nano structure based on crystallographic engineering, which comprises the following steps:
(1) pulsed laser deposition of (111) -oriented SrTiO3Single-sided epitaxial growth of (111) oriented SrRuO on substrates3A thin film bottom electrode;
(2) SrRuO in the step (1) by adopting a pulse laser deposition method3Epitaxially growing (111) -oriented Pb (Zr) on the upper surface of the thin film bottom electrode0.2Ti0.8)O3A film;
(3) the P in the step (2)b(Zr0.2Ti0.8)O3The film is heated at 50-60 ℃ per minute-1Cooling to room temperature at a cooling rate, and applying a circulating external electric field to the Pb (Zr)0.2Ti0.8)O3And forming a multilevel multi-domain nano structure in the film to obtain the perovskite ferroelectric film with the multilevel multi-domain nano structure.
The invention adopts a pulse laser deposition method to prepare (111) -oriented SrTiO3Single-sided epitaxial growth of (111) oriented SrRuO on substrates3A thin film bottom electrode. The invention is directed to said SrTiO3The substrate is not particularly limited, and SrTiO having (111) orientation well known to those skilled in the art is used3The substrate is commercially available. In the present invention, SrTiO3Substrate and Pb (Zr)0.2Ti0.8)O3Having a similar lattice structure and good lattice matching, SrTiO3Stress regulation of the substrate will be via SrRuO3Film conduction to Pb (Zr)0.2Ti0.8)O3Thin film, further capable of being in SrRuO3Growing high-quality Pb (Zr) epitaxially on the upper surface of the film0.2Ti0.8)O3A film.
In the present invention, the operating conditions of the pulsed laser deposition method preferably include: the reaction chamber is vacuumized to be less than or equal to 1 multiplied by 10-6Pa; the deposition temperature is 650-700 ℃; the deposition oxygen pressure is 50-100 mtorr; the laser energy density is 1.7Jcm-2(ii) a The laser pulse frequency was 10 Hz.
In the present invention, the SrRuO3The thickness of the thin film bottom electrode is preferably 5-25 nm. In the present invention, SrRuO3Has high conductivity, high chemical stability and thermal stability, and is compatible with Pb (Zr)0.2Ti0.8)O3Has similar lattice structure and good lattice matching property, and can epitaxially grow high-quality Pb (Zr) on the upper surface of the crystal0.2Ti0.8)O3A film.
SrTiO in (111) orientation3Single-sided epitaxial growth of SrRuO on a substrate3After the film bottom electrode, the invention adopts a pulse laser deposition method to deposit SrRuO3With (111) orientation of epitaxial growth on the upper surface of the thin film bottom electrodePb(Zr0.2Ti0.8)O3A film. In the present invention, the operating conditions of the pulsed laser deposition method preferably include: the reaction chamber is vacuumized to be less than or equal to 1 multiplied by 10-6Pa; the deposition temperature is 550-600 ℃; the oxygen pressure of the deposit is 100-150 mtorr; the laser energy density is 1.7 J.cm-2(ii) a The laser pulse frequency was 10 Hz.
In the SrRuO3Epitaxially growing (111) -oriented Pb (Zr) on the upper surface of the thin film bottom electrode0.2Ti0.8)O3After the film is formed, the invention uses the Pb (Zr)0.2Ti0.8)O3The film is heated at 50-60 ℃ per minute-1Cooling to room temperature at a cooling rate, and applying a circulating external electric field to the Pb (Zr)0.2Ti0.8)O3And forming a multilevel multi-domain nano structure in the film to obtain the perovskite ferroelectric film with the multilevel multi-domain nano structure. The invention leads the Pb (Zr) to be in the Pb (Zr) through rapid cooling0.2Ti0.8)O3Mismatch stress in the epitaxial film, preferentially released in the form of formation of multiple domain variants; at Pb (Zr)0.2Ti0.8)O3The domain configuration formed along the crystal direction with the greatest mismatch strain is most stable with the initial mismatch stress in the epitaxial film remaining constant.
In the present invention, the voltage of the cyclic external electric field is preferably +/-5 to +/-8V, and may be +/-5V, +/-6V, +/-7V or +/-8V. In the present invention, the number of times of application of the external electric field for the cycle is preferably 3 to 7 times. The invention is to (111) oriented Pb (Zr) after cooling0.2Ti0.8)O3Applying cyclic external electric field to the film to make the (111) oriented Pb (Zr)0.2Ti0.8)O3The disordered nano-domain structure in the thin film is converted to a single (a)1,c)/(a2And c) a multi-domain nano structure with multiple domains arranged in a band.
The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
(1) Pulsed laser deposition of (111) -oriented SrTiO3Single-sided epitaxial growth of (111) -oriented SrRuO with thickness of 5nm3A thin film bottom electrode; wherein the operating conditions of the pulsed laser deposition method include: the reaction chamber is vacuumized to be less than or equal to 1 multiplied by 10-6Pa, deposition temperature 690 deg.C, deposition oxygen pressure 80mtorr, laser energy density 1.7J · cm-2The laser pulse frequency is 10 Hz;
(2) SrRuO in the (1) by adopting a pulse laser deposition method3Epitaxially growing (111) -oriented Pb (Zr) with a thickness of 230nm on the upper surface of the thin film bottom electrode0.2Ti0.8)O3A film; wherein the operating conditions of the pulsed laser deposition method include: the reaction chamber is vacuumized to be less than or equal to 1 multiplied by 10-6Pa, deposition temperature of 600 deg.C, deposition oxygen pressure of 100mtorr, and laser energy density of 1.7J · cm-2The laser pulse frequency is 10 Hz;
(3) at 50 ℃ min-1Temperature reduction rate of Pb (Zr) in the step (2)0.2Ti0.8)O3The film was cooled to room temperature and then subjected to an external electric field of +/-6V cycles, under three alternating (+6V/-6V/+6V/-6V/+6V/-6V) polarizations of the external electric field in the Pb (Zr) phase0.2Ti0.8)O3And forming a multilevel multi-domain nano structure in the film to obtain the perovskite ferroelectric film with the multilevel multi-domain nano structure.
Pb (Zr) prepared in this example0.2Ti0.8)O3The multi-level multi-domain nano structure in the film is formed by1Domain, a2Domains and c-domains, and the multi-level multi-domain nanostructure is composed of a single (a)1,c)/(a2C) multi-domain bands are arranged, the structural schematic diagram of the multi-level multi-domain nano structure is shown in figure 1, wherein 1-a2A domain; 2-c domain; 3-a1A domain; 4-Probe applying a cyclic external electric field.
Comparative example 1
(1) By pulsed laser depositionMethod of making (111) -oriented SrTiO3Single-sided epitaxial growth of (111) -oriented SrRuO with thickness of 5nm3A thin film bottom electrode; wherein the operating conditions of the pulsed laser deposition method include: the reaction chamber is vacuumized to be less than or equal to 1 multiplied by 10-6Pa, deposition temperature 690 deg.C, deposition oxygen pressure 80mtorr, laser energy density 1.7J · cm-2The laser pulse frequency is 10 Hz;
(2) SrRuO in the step (1) by adopting a pulse laser deposition method3Epitaxially growing (111) -oriented Pb (Zr) with a thickness of 230nm on the upper surface of the thin film bottom electrode0.2Ti0.8)O3A film; wherein the operating conditions of the pulsed laser deposition method include: the reaction chamber is vacuumized to be less than or equal to 1 multiplied by 10-6Pa, deposition temperature of 600 deg.C, deposition oxygen pressure of 100mtorr, and laser energy density of 1.7J · cm-2The laser pulse frequency is 10 Hz;
(3) at 5 ℃ min-1Temperature reduction rate of Pb (Zr) in the step (2)0.2Ti0.8)O3The film was cooled to room temperature and then subjected to an external electric field of +/-7V cycles, under three alternating (+7V/-7V/+7V/-7V/+7V/-7V) polarizations of the external electric field in the Pb (Zr) phase0.2Ti0.8)O3And forming a multilevel multi-domain nano structure in the film to obtain the perovskite ferroelectric film with the multilevel multi-domain nano structure.
Pb (Zr) prepared by this comparative example0.2Ti0.8)O3The multi-level multi-domain nano structure in the film is formed by1Domain, a2The structure of the multilevel multi-domain nanostructure is shown in figure 2, wherein 1-a2A domain; 2-c domain; 3-a1A domain; 4-Probe applying a cyclic external electric field.
Comparative example 2
(1) Pulsed laser deposition of (001) -oriented SrTiO3Single-sided epitaxial growth of (001) -oriented SrRuO with thickness of 10nm3A thin film bottom electrode; wherein the operating conditions of the pulsed laser deposition method include: the reaction chamber is vacuumized to be less than or equal to 1 multiplied by 10-6Pa, deposition temperatureThe temperature is 690 ℃, the deposition oxygen pressure is 80mtorr, and the laser energy density is 1.7J · cm-2The laser pulse frequency is 10 Hz;
(2) SrRuO in the step (1) by adopting a pulse laser deposition method3Epitaxially growing (001) -oriented Pb (Zr) with a thickness of 200nm on the upper surface of the thin film bottom electrode0.2Ti0.8)O3A film; wherein the operating conditions of the pulsed laser deposition method include: the reaction chamber is vacuumized to be less than or equal to 1 multiplied by 10-6Pa, deposition temperature of 600 deg.C, deposition oxygen pressure of 100mtorr, and laser energy density of 1.7J · cm-2The laser pulse frequency is 10 Hz;
(3) at 50 ℃ min-1Temperature reduction rate of Pb (Zr) in the step (2)0.2Ti0.8)O3The film was cooled to room temperature and then subjected to an external electric field of +/-6V cycles, under three alternating (+6V/-6V/+6V/-6V/+6V/-6V) polarizations of the external electric field in the Pb (Zr) phase0.2Ti0.8)O3And forming a multilevel multi-domain nano structure in the film to obtain the perovskite ferroelectric film with the multilevel multi-domain nano structure.
Comparative example 3
(1) Pulsed laser deposition of (101) -oriented SrTiO3Single-sided epitaxial growth of (101) -oriented SrRuO with thickness of 8nm3A thin film bottom electrode; wherein the operating conditions of the pulsed laser deposition method include: the reaction chamber is vacuumized to be less than or equal to 1 multiplied by 10-6Pa, deposition temperature 690 deg.C, deposition oxygen pressure 80mtorr, laser energy density 1.7J · cm-2The laser pulse frequency is 10 Hz;
(2) SrRuO in the step (1) by adopting a pulse laser deposition method3Epitaxially growing (101) -oriented Pb (Zr) with a thickness of 210nm on the upper surface of the thin film bottom electrode0.2Ti0.8)O3A film; wherein the operating conditions of the pulsed laser deposition method include: the reaction chamber is vacuumized to be less than or equal to 1 multiplied by 10-6Pa, deposition temperature of 600 deg.C, deposition oxygen pressure of 100mtorr, and laser energy density of 1.7J · cm-2The laser pulse frequency is 10 Hz;
(3) at 50 ℃ min-1Rate of temperature decrease willPb (Zr) in step (2)0.2Ti0.8)O3The film was cooled to room temperature and then subjected to an external electric field of +/-6V cycles, under three alternating (+6V/-6V/+6V/-6V/+6V/-6V) polarizations of the external electric field in the Pb (Zr) phase0.2Ti0.8)O3And forming a multilevel multi-domain nano structure in the film to obtain the perovskite ferroelectric film with the multilevel multi-domain nano structure.
Example 2
The structures of the perovskite ferroelectric thin films with the multi-stage multi-domain nano structures prepared in the embodiment 1 and the comparative examples 1 to 3 are characterized as follows:
FIG. 3 is a PFM image of the perovskite ferroelectric thin film of example 1, wherein (c), the topography, (d), the out-of-plane amplitude plot, (e), the in-plane amplitude plot; FIG. 4 is a PFM image of the perovskite ferroelectric thin film in comparative example 1, wherein (f), the morphology map, (g), the out-of-plane amplitude map, (h), the in-plane amplitude map. As can be seen from FIGS. 3 and 4, the multi-level multi-domain nanostructure of the rapidly cooled perovskite ferroelectric thin film in example 1 is composed of a single (a)1,c)/(a2C) multi-band domain composition, i.e. as shown in the structural diagram of fig. 1; while the multi-level multi-domain nano structure of the perovskite ferroelectric thin film obtained in the comparative example 1 at the conventional cooling rate is formed by (a)1,a2)/(a1,c),(a1,a2)/(a2C) and (a)1,c)/(a2And c) three kinds of multi-band domains, namely as shown in the structural schematic diagram of FIG. 2.
FIG. 5 is a TEM image of the perovskite ferroelectric thin film prepared in example 1, wherein (a) is a bright field TEM image of a cross section of the in-situ grown perovskite ferroelectric thin film, (b) is a bright field TEM image of a cross section of the perovskite ferroelectric thin film after electric polarization, (c) is a high magnification TEM image of a multi-level multi-domain nanostructure (taken from the region circled in b); (a) the inset in the figure is the selected region electron diffraction pattern of the perovskite ferroelectric thin film; (b) the inset in the figure is a dark field TEM image (top left) and an in-plane PFM image in the same region. As shown in FIG. 5, the TEM image shows Pb (Zr) in example 10.2Ti0.8)O3The film is heteroepitaxially grown, and the Pb (Zr)0.2Ti0.8)O3The film has a complex nano twin domain structure pattern in a primary metastable state, and has a striped parallel multi-level multi-domain nano structure under the action of an external circulating electric field. The multi-level multi-domain nanostructure is composed of a single (a)1,c)/(a2And c) the multi-domain band composition is shown as the structural schematic diagram of FIG. 1. It was further confirmed by combining PFM and TEM images that the multi-level multi-domain nanostructure in the perovskite ferroelectric thin film prepared in example 1 consists of single (a)1,c)/(a2And c) multi-domain band composition (shown in FIG. 1).
The electrical properties of the perovskite ferroelectric thin films with the multi-stage multi-domain nano-structure prepared in example 1 and comparative examples 1 to 3 are characterized as follows (wherein, in order to test the hysteresis loop (i.e. PE) and the butterfly curve (i.e. CE) of the perovskite ferroelectric thin film, a platinum layer of point electrode needs to be grown on the perovskite ferroelectric thin film):
FIG. 6 is a graph comparing the hysteresis loops (i.e., PE) of the perovskite ferroelectric thin films prepared in example 1 and comparative examples 1 to 3; FIG. 7 is a comparison of butterfly curves (i.e., CEs) for the perovskite ferroelectric thin films prepared in example 1 and comparative examples 1-3. As can be seen from FIGS. 6 and 7, the (111) oriented Pb (Zr) composed of a single multi-domain band in example 10.2Ti0.8)O3The film was compared to three Pb (Zr) in comparative examples 1 to 30.2Ti0.8)O3The film has the minimum coercive electric field and the maximum dielectric response. And (111) oriented Pb (Zr) consisting of a single multi-domain band in example 10.2Ti0.8)O3The film was compared to (111) oriented Pb (Zr) consisting of three multi-domain bands in comparative experiment 10.2Ti0.8)O3The remanent polarization and the dielectric constant of the film are improved by about 25% and 50%, respectively.
Fig. 8 is a graph comparing fatigue curves of the perovskite ferroelectric thin films of example 1 and comparative example 1, and the inset is a graph comparing the hysteresis loops (i.e., PE) of the perovskite thin films of example 1 before and after the fatigue test. As shown in FIG. 8, the (111) orientation Pb (Zr) composed of a single multi-domain band in example 10.2Ti0.8)O3The fatigue resistance of the film was better than that of the (111) oriented Pb (Zr) composed of three kinds of multi-domain stripes in comparative example 10.2Ti0.8)O3Fatigue resistance of the film. Fig. 9 is a graph comparing fatigue curves of the perovskite ferroelectric thin films of comparative examples 2 and 3, and the inset is a graph comparing hysteresis loops (i.e., PE) of the perovskite thin films of comparative examples 2 and 3 before and after the fatigue test. As can be seen from FIGS. 8 and 9, the (111) oriented Pb (Zr) composed of a single multi-domain band in example 10.2Ti0.8)O3The fatigue resistance of the film is better than that of Pb (Zr) in comparative example 2 and comparative example 30.2Ti0.8)O3Fatigue resistance of the film.
As can be seen from the above examples, the present invention provides a perovskite ferroelectric thin film in which the multi-level multi-domain nanostructure is composed of a single (a)1,c)/(a2And c) the multi-domain zones are arranged, so that the electrical property of the perovskite ferroelectric film is enhanced, and compared with the perovskite ferroelectric film without the multi-stage multi-domain nano structure, the ferroelectric polarization is enhanced besides the reduction of coercive field and the enhancement of dielectric response, and the fatigue resistance is greatly improved.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.
Claims (8)
1. A preparation method of perovskite ferroelectric thin film with multi-level and multi-domain nano structure based on crystallography engineering comprises the following steps:
(1) pulsed laser deposition of (111) -oriented SrTiO3Single-sided epitaxial growth of (111) oriented SrRuO on substrates3A thin film bottom electrode;
(2) SrRuO in the step (1) by adopting a pulse laser deposition method3Epitaxially growing (111) -oriented Pb (Zr) on the upper surface of the thin film bottom electrode0.2Ti0.8)O3A film;
(3) adding Pb (Zr) in the step (2)0.2Ti0.8)O3The film is heated at 50-60 ℃ per minute-1Cooling down to room temperature at a cooling rate and then applying cyclesAn electric field outside the ring at said Pb (Zr)0.2Ti0.8)O3Forming a multilevel multi-domain nano structure in the film to obtain a perovskite ferroelectric film with the multilevel multi-domain nano structure;
the multilevel multidomain nano structure is formed by arranging single (a1, c)/(a2, c) multidomain bands, wherein the perovskite ferroelectric thin film is (111) oriented Pb (Zr)0.2Ti0.8)O3And (3) epitaxial thin films.
2. The method according to claim 1, wherein the operating conditions of the pulsed laser deposition method in the step (1) include: the reaction chamber is vacuumized to be less than or equal to 1 multiplied by 10-6Pa; the deposition temperature is 650-700 ℃; the deposition oxygen pressure is 50-100 mtorr; the laser energy density is 1.7 J.cm-2(ii) a The laser pulse frequency was 10 Hz.
3. The preparation method according to claim 1 or 2, wherein the SrRuO is3The thickness of the film bottom electrode is 5-25 nm.
4. The method according to claim 1, wherein the operating conditions of the pulsed laser deposition method in the step (2) include: the reaction chamber is vacuumized to be less than or equal to 1 multiplied by 10-6Pa; the deposition temperature is 550-600 ℃; the oxygen pressure of the deposit is 100-150 mtorr; the laser energy density is 1.7 J.cm-2(ii) a The laser pulse frequency was 10 Hz.
5. The production method according to claim 1, wherein the voltage of the external electric field for the cycle in the step (3) is +/-5 to +/-8V.
6. The production method according to claim 1 or 5, wherein the number of times of application of the external electric field is circulated in the step (3) is 3 to 7 times.
7. The method according to claim 1, wherein the thickness of the perovskite ferroelectric thin film is not less than 100 nm.
8. The production method according to claim 1, wherein the thickness of the perovskite ferroelectric thin film is 200 to 250 nm.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201810826422.2A CN108987560B (en) | 2018-07-25 | 2018-07-25 | Perovskite ferroelectric film with multilevel multi-domain nano structure based on crystallography engineering and preparation method thereof |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201810826422.2A CN108987560B (en) | 2018-07-25 | 2018-07-25 | Perovskite ferroelectric film with multilevel multi-domain nano structure based on crystallography engineering and preparation method thereof |
Publications (2)
Publication Number | Publication Date |
---|---|
CN108987560A CN108987560A (en) | 2018-12-11 |
CN108987560B true CN108987560B (en) | 2022-02-01 |
Family
ID=64550595
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201810826422.2A Active CN108987560B (en) | 2018-07-25 | 2018-07-25 | Perovskite ferroelectric film with multilevel multi-domain nano structure based on crystallography engineering and preparation method thereof |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN108987560B (en) |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6514835B1 (en) * | 1998-03-03 | 2003-02-04 | Advanced Technology Materials, Inc. | Stress control of thin films by mechanical deformation of wafer substrate |
CN1937274A (en) * | 2005-09-23 | 2007-03-28 | 清华大学 | Ferroelectric domain array structure, and its preparing method and ferroelectric film having same |
CN101107724A (en) * | 2005-01-19 | 2008-01-16 | 佳能株式会社 | Piezoelectric device, piezoelectric substance film production method, liquid delivery head and liquid delivery device |
CN101139202A (en) * | 2006-09-04 | 2008-03-12 | 日本碍子株式会社 | Piezoelectric/electrostrictive body, manufacturing method of the same, and piezoelectric/electrostrictive element |
CN101258620A (en) * | 2005-09-05 | 2008-09-03 | 佳能株式会社 | Epitaxial oxide film, piezoelectric film, piezoelectric film element, and liquid delivery head and liquid delivery apparatus using piezoelectric element |
CN105313466A (en) * | 2014-07-01 | 2016-02-10 | 精工爱普生株式会社 | Piezoelectric element, piezoelectric actuator device, liquid ejecting head, liquid ejecting apparatus, and ultrasonic measuring apparatus |
CN107093664A (en) * | 2017-04-19 | 2017-08-25 | 北京大学 | The big strain piezoelectric actuator and preparation method of a kind of periodicity cross polarization |
WO2018081809A1 (en) * | 2016-10-31 | 2018-05-03 | Quest Integrated, Llc | Single-crystal perovskite solid solutions with indifferent points for epitaxial growth of single crystals |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP4224709B2 (en) * | 2004-05-17 | 2009-02-18 | セイコーエプソン株式会社 | Piezoelectric element, piezoelectric actuator, ink jet recording head, ink jet printer, surface acoustic wave element, frequency filter, oscillator, electronic circuit, thin film piezoelectric resonator, and electronic device |
-
2018
- 2018-07-25 CN CN201810826422.2A patent/CN108987560B/en active Active
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6514835B1 (en) * | 1998-03-03 | 2003-02-04 | Advanced Technology Materials, Inc. | Stress control of thin films by mechanical deformation of wafer substrate |
CN101107724A (en) * | 2005-01-19 | 2008-01-16 | 佳能株式会社 | Piezoelectric device, piezoelectric substance film production method, liquid delivery head and liquid delivery device |
CN101258620A (en) * | 2005-09-05 | 2008-09-03 | 佳能株式会社 | Epitaxial oxide film, piezoelectric film, piezoelectric film element, and liquid delivery head and liquid delivery apparatus using piezoelectric element |
CN1937274A (en) * | 2005-09-23 | 2007-03-28 | 清华大学 | Ferroelectric domain array structure, and its preparing method and ferroelectric film having same |
CN101139202A (en) * | 2006-09-04 | 2008-03-12 | 日本碍子株式会社 | Piezoelectric/electrostrictive body, manufacturing method of the same, and piezoelectric/electrostrictive element |
CN105313466A (en) * | 2014-07-01 | 2016-02-10 | 精工爱普生株式会社 | Piezoelectric element, piezoelectric actuator device, liquid ejecting head, liquid ejecting apparatus, and ultrasonic measuring apparatus |
WO2018081809A1 (en) * | 2016-10-31 | 2018-05-03 | Quest Integrated, Llc | Single-crystal perovskite solid solutions with indifferent points for epitaxial growth of single crystals |
CN107093664A (en) * | 2017-04-19 | 2017-08-25 | 北京大学 | The big strain piezoelectric actuator and preparation method of a kind of periodicity cross polarization |
Non-Patent Citations (3)
Title |
---|
Ferroelectric polarization reversal via successive ferroelastic transitions;Xu R , Liu S , Grinberg I , et al.;《Nature Materials》;20141026;第14卷(第1期);全文 * |
Polydomain structures in ferroelectric and ferroelastic epitaxial films;Roytburd A L , Ouyang J , Artemev A .;《Journal of Physics Condensed Matter》;20170315;第29卷(第16期);全文 * |
Stationary domain wall contribution to enhanced ferroelectric susceptibility;Xu R , Karthik J , Damodaran A R , et al.;《Nature Communications》;20140116;第5卷;摘要部分,第3页第2栏第2段,附图2 * |
Also Published As
Publication number | Publication date |
---|---|
CN108987560A (en) | 2018-12-11 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20210310149A1 (en) | Single crystalline metal foil and manufacturing method therefor | |
JP2021193738A (en) | Film structure and film-forming device | |
US9825182B2 (en) | Method of intercalating insulating layer between metal and graphene layer and method of fabricating semiconductor device using the intercalation method | |
Giencke et al. | Tailoring the domain structure of epitaxial BiFeO3 thin films | |
US6728093B2 (en) | Method for producing crystallographically textured electrodes for textured PZT capacitors | |
Wasa et al. | Highly polarized single-c-domain single-crystal Pb (Mn, Nb) O 3-PZT thin films | |
US8029924B2 (en) | Thin film template for fabrication of two-dimensional quantum dot structures | |
CN108987560B (en) | Perovskite ferroelectric film with multilevel multi-domain nano structure based on crystallography engineering and preparation method thereof | |
Rojas et al. | Strain fields and electronic structure of antiferromagnetic CrN | |
Lazarov et al. | Selected growth of cubic and hexagonal GaN epitaxial films on polar MgO (111) | |
US6853535B2 (en) | Method for producing crystallographically textured electrodes for textured PZT capacitors | |
Little et al. | Equilibrium microstructure of epitaxial thin films | |
Hong et al. | Structure and electrical properties of Pb (ZrxTi1− x) O3 deposited on textured Pt thin films | |
Quan et al. | Spontaneous Line Defect‐Induced Co4Te7 Superlattices on SrTiO3 (001) Featuring Flat Bands | |
Jiang et al. | Epitaxial 0.65 PbMg1/3Nb2/3O3–0.35 PbTiO3 (PMN–PT) thin films grown on LaNiO3/CeO2/YSZ buffered Si substrates | |
Sumi et al. | MOCVD growth of epitaxial SrIrO3 films on (111) SrTiO3 substrates | |
JP6937518B2 (en) | Membrane structure and its manufacturing method | |
Sakai et al. | Characterization of ferroelectric property of c-axis-and non-c-axis-oriented epitaxially grown Bi2VO5. 5 thin films | |
Xiao et al. | Optimizing energy storage performance of 0.9 (Na0. 5Bi0. 5)(Fe0. 02Ti0. 98) O3-0.1 SrTiO3 flexible capacitor via relaxation strategy | |
JP5212968B2 (en) | Element substrate and manufacturing method thereof | |
CN104480427A (en) | Preparation method of zinc oxide based diluted magnetic semiconductor thin film and in-situ regulation and control method of charge concentration of zinc oxide based diluted magnetic semiconductor thin film | |
Lee et al. | Self-limiting behavior of the grain growth in lead zirconate titanate thin films | |
Yu et al. | Effect of precursor solution concentration on the grain orientation of Bi3. 15Nd0. 85Ti3O12 thin films | |
Szafraniak et al. | Hydrothermal growth of nanosize ferroelectrics | |
Zhai et al. | Phase transformation behavior of (Pb, La)(Zr, Sn, Ti) O 3 and Pb (Nb, Zr, Sn, Ti) O 3 antiferroelectric thin films deposited on LaNiO 3-buffered silicon substrates by sol-gel processing |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
GR01 | Patent grant | ||
GR01 | Patent grant |