JPH11103024A - Ferroelectric capacitor and semiconductor device therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a capacitor utilizing a highly-oriented ferroelectric crystalline thin film that is grown reproducibly, and a semiconductor device therewith. SOLUTION: A capacitor consists of a lower electrode 13 having a (111) oriented crystalline structure, a ferroelectric material thin film 12 consisting of crystalline grains aligned to form a stacking layered structure, and an upper electrode 11, wherein more than 80% of the stacking orientation (c axis) of the single-crystalline cells of the crystalline grains lie in the direction 54.7 deg. (or 35.3 deg.) from the interface with the lower electrode 13. Such a ferroelectric material thin film 12 can be grown reproducibly with an epitaxial growth method. A semiconductor device, such as an FeRAM(ferroelectric random access memory), is obtained using the capacitor stated above.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an FeRAM (Ferroelectonic Random Acce
The present invention relates to a ferroelectric element such as an ss memory and a semiconductor device using the same.

[0002]

2. Description of the Related Art In recent years, a non-volatile semiconductor memory FeRAM using a ferroelectric material as a capacitor material has attracted attention.
Since FeRAM uses two remanent polarizations having different polarities, it has a characteristic that the memory can be retained even when the power is turned off. Furthermore, the rewriting speed is very high, less than μ seconds, and research is proceeding as an ideal next-generation memory.

[0003] In such a nonvolatile memory, a ferroelectric material which causes little deterioration in characteristics due to writing is required. SrBi ₂ Ta ₂ O ₉ is a ferroelectric material satisfying this requirement.
(Abbreviated as SBT). This ferroelectric material has a layered structure, that is, a structure in which a plurality of unit crystal vesicles made of a ferroelectric material are stacked to form one crystal phase. Generally, of the three crystal axes of the ferroelectric material, the crystal axis along the stacking direction of the unit crystal vesicles in this layered structure is called a c-axis, and one of the two crystal axes orthogonal to the c-axis is defined as one. a axis, the other b
Called the axis.

It is known that this Bi layered ferroelectric material has a large crystal anisotropy and does not have polarization in a direction parallel to the c-axis. In a memory using a ferroelectric thin film made of this material, the ferroelectric thin film is non-oriented or c-axis oriented (that is, the c-axis is oriented perpendicular to the substrate surface), so that a high polarization amount is obtained. Can not get.

In order to increase the capacity of the capacitor, attempts have been made to orient the crystals of the ferroelectric material in one direction. For example, JP-A-7-54007 discloses a ferroelectric element in which the c-axis of a ferroelectric thin film is oriented within ± 30 degrees with respect to a direction perpendicular to an electric field applied to a pair of electrodes. Have been.

[0006]

However, these Bis
The ferroelectric thin film having a layered structure has a problem in that the c-axis is difficult to grow in parallel with the electrode, and stable growth of crystals cannot be obtained. Therefore, an object of the present invention is to provide a ferroelectric element capable of forming a highly oriented ferroelectric thin film by stable crystal growth, and a semiconductor device using the same.

[0007]

The problem of the prior art described above is due to the mismatch of the lattice constant between the electrode and the ferroelectric material. Since the above-mentioned ferroelectric thin film having the Bi layer structure has a crystal structure having two Bi-O layers shifted by a half cycle, the interlayer distance between the two Bi-O layers, the Bi-O layer and the Sr- The distance between the O layers is different. For this reason, it was very difficult to perform effective alignment control.

The inventors of the present invention have conducted intensive studies focusing on the lattice constant between the electrode and the ferroelectric material. As a result, the crystal constituting at least the surface of the lower electrode which is in contact with the ferroelectric thin film is (11).
1) In the case of plane orientation, the ferroelectric thin film is epitaxially grown so that the angle of the c-axis is 50.7 ° or more and 58.7 ° or less (preferably, with respect to the interface between the lower electrode and the ferroelectric thin film). 54.7 °), or 31.3 ° or more.
It has been found that crystals of a ferroelectric thin film of 3 ° or less (preferably 35.3 °) can be grown stably, and a high polarization amount can be realized in the obtained ferroelectric element.

Here, this principle will be described taking the case of the above-mentioned SBT as an example. This compound is represented by the following general formula (Bi ₂ O ₂ ) ²⁺ (where A is Bi element, B site is Sr element, C site is Ta element and y is ₂ ). Sr ₁ Ta ₂ O ₇ ) ^2- . The crystal structure of this SBT is a Bi layered structure having two Bi-O layers, where a-axis = b-axis = 3.89 angstroms and c-axis = 25.10 angstroms.

(AO) ²⁺ (B _y-1 C _y O _{3y + 1} ) ^2- ( _{Formula 1} ) When Pt metal is used for the lower electrode, the Pt metal has a cubic (Cubic) structure. Lower electrode 13 from preferential growth
Becomes (111) plane orientation. The lattice constant of this Pt metal was a axis = b axis = c axis = 3.9231 Å from crystal analysis.

The lattice constant of the SBT (a axis = b axis = 3.89)
Angstrom) and the lattice constant of Pt (a-axis = b-axis =
The mismatch with c-axis = 3.9231 angstroms) is as small as 0.85%. For this reason, it is considered that the epitaxial growth of the SBT thin film on the Pt metal is very stable. According to the epitaxial growth of SBT on the Pt (111) plane sharing three sides of the crystal axis, as shown in FIG. An orientation inclined at 54.7 ° can be formed stably. Further, according to the epitaxial growth of SBT on Pt (111) plane sharing only one side of the crystal axis, as shown in FIG.
The c-axis of the crystal structure 2 is 3 with respect to the interface with the lower electrode 13.
The ferroelectric thin film 12 oriented at an inclination of 5.3 ° can be formed stably. Note that hatching of the ferroelectric thin film 12 is omitted for easy viewing of the drawing.

By forming the ferroelectric thin film 12 using these epitaxial growths, it is possible to suppress a decrease in breakdown voltage characteristic due to a leak current and a decrease in polarization value due to a random polarization direction, which are observed in a conventional non-oriented SBT thin film. It becomes possible to obtain an operating voltage and a capacitor capacity which are indispensable for the memory operation. Further, remanent polarization having a large polarization amount with a uniform polarization axis can be obtained, and a ferroelectric element having high withstand voltage characteristics can be stably manufactured.

The c of all the crystal grains of the ferroelectric thin film
The axis need not be at 54.7 ° or 35.3 °. The c-axis of each crystal grain in the ferroelectric thin film usually has some variation as shown in FIGS. 4A and 4B. However, the c-axis of crystal grains of 80% or more (vol / vol) is 54.7 ° ± 4 ° or 3
At 5.3 ° ± 4 °, a good memory operation can be obtained.

Based on the above new findings, the present invention comprises a lower electrode, a ferroelectric thin film and an upper electrode which are stacked in this order, and forms at least a surface of the lower electrode which is in contact with the ferroelectric thin film. A ferroelectric device in which a crystal has a (111) plane orientation, wherein a ferroelectric thin film has a layered structure in which a plurality of unit crystal vesicles made of a ferroelectric material are stacked to form one crystal phase. The c-axis (that is, the stacking direction of the unit crystal vesicles) of the crystal grains containing 80% to 100% (vol / vol) of the crystal grains includes the lower electrode and the ferroelectric thin film. (1) a ferroelectric element oriented at an angle of not less than 50.7 ° and not more than 58.7 ° (preferably 54.7 °), and (2) not less than 31.3 ° and not more than 39. Ferroelectric element oriented at an angle of 0.3 ° or less (preferably 35.3 °) Two elements are provided.
Note that the ferroelectric thin film preferably has a layered perovskite structure.

Further, the present invention provides a semiconductor device having the ferroelectric element of the present invention. The ferroelectric element of the present invention is particularly suitable as a capacitor having a field-effect transistor structure in a semiconductor device.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION As a ferroelectric material used in the device of the present invention, a compound represented by the following general formula (Formula 1) is suitable. Each of these compounds has a layered perovskite structure having a lattice constant of about a axis = b axis = about 3.9 angstroms, and therefore has an orientation that enables a high polarization amount to be obtained by epitaxial growth, as in the case of the SBT described above. Crystals can be grown stably.

(AO) ²⁺ (B _y-1 C _y O _{3y + 1} ) ^2- (Chemical Formula 1) In the above formula (Chemical Formula 1), the A site is Tl, H
g, Pb, Bi and rare earth elements (Y, Ce, Pr, N
d, Pm, Eu, Gd, Tb, Dy, Ho, Er, T
m, Yb, Lu). The B site is at least one selected from Bi, Pb, Ca, Sr and Ba. When the B site is composed of a plurality of elements, the ratio can be arbitrarily selected. C site is Ti, Nb, T
When at least one of a, W, Mo, Fe, Co, Cr and Zr is used and the C site is made of a plurality of elements, the ratio can be arbitrarily selected. y is an integer of 2 to 5.

It is preferable that A is Pb or Bi, B is Bi, Pb and / or Sr, and C is Nb and / or Ta because of high stability in forming a ferroelectric thin film.

As the material for the lower electrode of the ferroelectric device of the present invention, any electrode material may be used as long as it is a material having excellent oxidation resistance, but a platinum group element or its alloy or oxide is used. be able to. In particular, platinum is suitable for the element of the present invention because ferroelectric elements can be produced with good mass productivity by using platinum.

Further, a first conductive oxide having a perovskite structure may be used as a material of the lower electrode of the ferroelectric element of the present invention. If a conductive oxide is used at least in a portion of the lower electrode that is in contact with the ferroelectric thin film, two oxide layers are formed at the interface between the ferroelectric thin film and the electrode. Layer) can be suppressed.

The first conductive oxide includes ReO ₃ ,
SrReO ₃ , BaReO ₃ , LaTiO ₃ , SrVO ₃ ,
CaCrO ₃ , SrCrO ₃ , SrFeO ₃ , La _1-x Sr
_x CoO ₃ (0 <x <0.5), LaNiO ₃ , CaRu
O ₃ , SrRuO ₃ , SrTiO ₃ , or BaPbO ₃
And any of the perovskites. First
It is desirable that the resistivity of the conductive oxide is 1 mΩ · cm or less. Among them, SrRuO ₃ is particularly preferable because it can be synthesized stably.

Further, as the lower electrode of the ferroelectric element of the present invention, a laminated film made of a plurality of kinds of materials may be used. In particular, a first layer made of a metal, a second layer made of a second conductive oxide that is an oxide of a single element, stacked in this order,
In addition, it is preferable to use a stacked film including the third layer made of the above-described first conductive oxide as the lower electrode, because the adhesion between the layers is improved. In such a case, the third layer, that is, the first conductive oxide forms an interface with the ferroelectric thin film.

The material of the first layer is Pt, A
Metals such as u, Al, Ni, Cr, Ti, Mo, and W can be used.

The second conductive oxide may be Ti
_{O x, VO x, EuO,} CrO 2, MoO 2, WO 2, Ph
O, OsO, IrO, PtO, ReO ₂ , RuO ₂ , Sn
O ₂ or the like can be used. Of these oxides, titanium oxide, iridium oxide, ruthenium oxide
It is particularly preferable because it can be synthesized stably. Desirably, the resistivity of the second conductive oxide is also 1 mΩ · cm or less.

As a method for forming the lower electrode or the upper electrode, a spin coating method, a coating method using an organic metal or an acetate, a spray method or a mist method, an MOCVD method, or the like.
(Metal-organic chemical vapor deposition) method, sputtering method, MBE (molecular beam epitaxy) method, laser evaporation method, or the like can be used as appropriate. Further, a barrier layer or the like may be appropriately provided between the base substrate and the lower electrode.

The ferroelectric thin film may be formed by a spin coating method, a coating method using an organic metal or an acetate, a spray method or a mist method, an MO method, or the like.
A CVD method, a sputtering method, an MBE method, a laser evaporation method, or the like can be used as appropriate.
Relaxing conditions for epitaxial growth of the crystal. After the ferroelectric raw material composition is formed into a film by the above-described method, a ferroelectric thin film may be formed by performing a low-temperature heat treatment for epitaxially growing a crystal.

The conditions for epitaxially growing the crystal are determined according to the type of the ferroelectric material to be formed, the type of the underlying electrode, and the like. For example, the precursor film is formed by the ordinary film forming method as described above. After that, the crystal can be epitaxially grown by heating and annealing at a temperature near the crystallization temperature (580 ° C. in the case of the above-mentioned SBT).

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings, but the present invention is not limited to these embodiments.

<Embodiment 1> In this embodiment, SBT is used as a ferroelectric material, and as shown in FIG.
A lower electrode 13, a ferroelectric layer 12, and an upper electrode 11
Was fabricated as follows.

First, as the base substrate 24, 30
Thickness 200 by sputtering while heating to 0 ° C
A Si wafer was prepared in which a predetermined pattern of a barrier layer (not shown) made of Angstrom Ti was formed, and a predetermined pattern of an SiO ₂ layer (not shown) was formed by thermal oxidation. On the surface of the barrier layer of the base substrate 24,
As the lower electrode 13, a Pt thin film having a thickness of 1000 Å was formed by a sputtering method while heating to 350 ° C. This Pt thin film was analyzed by X-ray diffraction analysis (1
11) The surface was a highly oriented film.

The ferroelectric thin film 12 was formed on the surface of the obtained lower electrode 13. The ferroelectric thin film 12 is made of Bi, Sr,
Sputtering method using an oxide target containing a Ta element (O ₂ / Ar + O ₂ : 5 to 50%, RF power: 1.0 to
A precursor thin film having a thickness of 1000 Å was formed at 1.6 kW at a substrate temperature of 350 ° C. to 490 ° C., and then heat-treated at 580 ° C. to 650 ° C. for 10 to 60 minutes.

The composition ratio of the obtained ferroelectric layer was determined by ICP (in
Inductively coupled plasma)
It is shown in Table 1. From this analysis result, the heat treatment temperature was 580 ° C.
650 ° C., the stoichiometric composition (Sr: B
i: Ta = 1: 2: 2) was obtained.

[0033]

[Table 1]

The obtained ferroelectric layer 12 has θ
When X-ray diffraction measurement of -2θ was performed, as shown in FIG. 7, Pt (1
11) No detection was possible except for the peak of the plane.
In the measurement at 4.7 °, a peak due to the (00n) plane of the SBT thin film was detected. As a result, it was confirmed that the obtained ferroelectric layer 12 was an alignment film whose c-axis was inclined by 54.7 °. Further, from the pole figure measurement, it was found that the c-axis of the crystal grains of almost 100% (volume / volume) of the whole ferroelectric was 50.7 ° or more and 58.7 ° or less.

Finally, the upper electrode 11 made of Pt was formed on the surface of the ferroelectric layer 12 by sputtering, and the intended ferroelectric element 14 was obtained. The orientation of the ferroelectric element 14 manufactured according to the present embodiment is controlled so as to face a fixed direction with respect to an applied electric field. Therefore, the coercive electric field (E
c) was reduced and a large remanent polarization (Pr) was obtained. When the characteristics of the element 14 of this example were measured,
Is 16 μC / cm ² and Ec is 40 kV /
cm, and when the writing by ± inversion of the voltage of 3 V was repeated 10 ¹⁵ times, the characteristic deterioration was about 3%, indicating excellent ferroelectric characteristics. Further, since the ferroelectric thin film 12 is composed of an aggregate of crystal grains oriented in the same direction, the leak current flowing through the grain boundary is 1 × 10 ^{−7 at} 5 V.
A / cm ² or less, and very excellent withstand voltage characteristics were obtained.

<Embodiment 2> A lower electrode 13 is formed on the surface of a base substrate 24 in the same manner as in Embodiment 1, and a sputtering method (O) is performed on the surface using an oxide target containing Bi, Sr, and Ta elements. ₂ / Ar + O ₂ : 5 to 20%, RF power: 1.0 to 1.3 kW, substrate temperature 460 ° C. to 490
C.) to form a precursor thin film having a thickness of 1000 Å, and then heat-treated at 660 ° C. to 800 ° C. for 10 to 60 minutes to form a ferroelectric thin film 12.

With respect to the obtained ferroelectric layer 12, θ-2θ
The X-ray diffraction measurement showed that a peak attributable to the (00n) plane of the SBT thin film was detected in the measurement at an α angle of 35.3 °. Thereby, the obtained ferroelectric layer 12
Was confirmed to be an alignment film whose c-axis is inclined by 35.3 °. Also, from the pole figure measurement, the c-axis of almost 100% (volume / volume) crystal grains of the entire ferroelectric was
It turned out that it is 31.3 degrees or more and 39.3 degrees or less.

Finally, the upper electrode 11 is formed in the same manner as in the first embodiment.
Was formed to produce the ferroelectric element 14. The orientation of the obtained ferroelectric element 14 is controlled so as to face a fixed direction with respect to an applied electric field. Therefore, 2Pr at 3V
Was 16 μC / cm ² , Ec was 35 kV / cm, and the characteristics were degraded by about 3% when writing was repeated 10 ¹⁵ times by ± inversion of a voltage of 3 V, showing excellent ferroelectric characteristics.

<Embodiment 3> In Embodiment 1, the base electrode 13
Although a single-layer film made of Pt was formed as shown in FIG. 5, in the present embodiment, as shown in FIG. 5, the film is composed of a metal layer 54, a second conductive oxide layer 53, and a first conductive oxide layer 52. The laminated film was formed as the base electrode 13. Hereinafter, the manufacturing process will be described.

First, a 1000 .ANG.-thick Ru metal layer 52 was formed on the surface of the undersubstrate 24 in the same manner as in Example 1 by sputtering while heating at 600.degree.
A second conductive oxide (RuO) layer 53 having a thickness of 1000 Å is formed on the surface thereof by sputtering while heating to 450 ° C. in an oxygen gas atmosphere. 1
000 angstroms of the first conductive oxide (SrR
The uO ₃ ) layer 52 was formed. As described above, the lower electrode 23 made of a three-layer laminated film was formed.

The ferroelectric layer 12 made of SBT was formed on the surface of the lower electrode 23 in the same manner as in the first embodiment. As a result of the same X-ray diffraction as in Example 1, the obtained ferroelectric thin film 12 was found to have an orientation in which the c-axis was inclined at 54.7 °. 50.7 ° or more from the pole figure measurement
It was found that the ratio of crystal grains oriented at an angle of 8.7 ° or less was 90% (volume / volume) of the entire ferroelectric.

Finally, the upper electrode 11 was formed on the surface of the ferroelectric thin film 12 in the same manner as in Example 1, and the ferroelectric element 50 shown in FIG. 5 was obtained.

In this embodiment, the ferroelectric material 1 of the lower electrode 23
Although the first conductive oxide having a perovskite structure was used at a position in contact with No. 2, as in the case of Example 1 using Pt,
Since the lattice constant between the ferroelectric substance 12 and its base (the first conductive oxide in this example) is good, a highly oriented ferroelectric thin film 12 could be formed by epitaxial growth.

Further, since both the ferroelectric 12 and the lower electrode 13 are oxides, the formation of an oxygen-deficient layer generally observed at the interface between the ferroelectric and the metal electrode was suppressed in this embodiment. As a result, in this example, excellent characteristics of low Ec and high Pr were obtained, and a decrease in Pr due to voltage inversion could be suppressed.

Further, in this embodiment, the metal layer 54, the second conductive oxide 53, and the first conductive oxide layer 52 are laminated on the surface of the base substrate 24 in this order, so that Good adhesion was obtained. Further, since the first conductive oxide layer 52 is formed on the surface of the second conductive oxide layer 53, the orientation of the second conductive oxide layer 53 is used to make the surface of the second conductive oxide layer 53 available. It is possible to control the orientation of the first conductive oxide layer 52 to be (111) plane orientation. Therefore, according to the present embodiment, a highly oriented ferroelectric thin film can be stably formed on the surface of the first conductive oxide layer 52, similarly to the first embodiment using Pt. Was.

Embodiment 4 In this embodiment, a semiconductor device including a ferroelectric element having the same structure as that of Embodiment 1 was manufactured as a capacitor having a field effect transistor structure. FIG. 6 shows the structure of the semiconductor device obtained according to this embodiment.

First, after a diffusion layer 67 is formed on a Si wafer 65 by ion implantation and heat treatment, a Ti barrier layer 62 is formed by sputtering, a SiO ₂ gate film 69 is formed by surface oxidation, and a gate electrode 68 is further formed thereon. Formed. Then, after forming the SiO ₂ film 66 as an isolation between the transistor and the capacitor, the SiO ₂
A lower electrode 13 made of Pt, a ferroelectric thin film 12 made of SBT, and a Pt
Was formed in this order. Subsequently, an SiO ₂ film 64 for element isolation is formed, and the upper electrode 11 is formed.
Aluminum wiring 61 for connection between the silicon and diffusion layer 67 was formed. As described above, the semiconductor device 60 of the ferroelectric element
was gotten.

In the semiconductor device 60 obtained according to the present embodiment, as in the first embodiment, the ferroelectric thin film has a c-axis tilt as high as 54.7 ° with respect to the interface with the base electrode. It was an alignment film, and its ferroelectric properties were as good as in Example 1. Semiconductor device 6 obtained by this embodiment
Reference numeral 0 denotes a semiconductor device that can detect the signals “0” and “1” based on the change in the storage capacitance obtained by the voltage of 3V.

[0049]

As described above, in the ferroelectric element and the semiconductor device of the present invention, a highly oriented high Pr and low Ec can be obtained by the stable growth of the ferroelectric thin film crystal by epitaxial growth from the lower electrode. Since an excellent ferroelectric layer can be easily formed, excellent ferroelectric characteristics can be stably realized.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a ferroelectric thin film of the present invention.

FIG. 2 is a partial cross-sectional view illustrating a structure of a ferroelectric element of Example 1.

FIG. 3 is a schematic view showing a ferroelectric thin film of the present invention.

FIG. 4 is a graph showing a distribution of orientation of a ferroelectric thin film.

FIG. 5 is a partial cross-sectional view illustrating a structure of a ferroelectric element of Example 3.

FIG. 6 is a partial cross-sectional view illustrating a structure of a semiconductor device according to a fourth embodiment.

FIG. 7 shows the X of the ferroelectric thin film formed in Example 1.
It is a graph which shows the measurement result of a line diffraction.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 11 ... Upper electrode, 12 ... Ferroelectric thin film, 13 ... Lower electrode, 14 ... Ferroelectric element, 23 ... Lower electrode, 24 ... Base substrate, 50 ... Ferroelectric element, 52 ... First conductive oxide Layer, 53: second conductive oxide layer, 54: metal layer, 60
... semiconductor device, 61 ... aluminum wiring, 62 ... barrier layer, 64 ... SiO ₂ film, 65 ... Si wafer, 66 ... Si
O ₂ film, 67: diffusion layer, 68: gate electrode, 69: Si
O ₂ gate film.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI H01L 29/788 29/792

Claims (13)

[Claims] 1. A ferroelectric device comprising a lower electrode, a ferroelectric thin film, and an upper electrode stacked in this order, wherein the lower electrode has at least a crystal constituting a surface in contact with the ferroelectric thin film, The ferroelectric thin film is oriented in a (111) plane, and includes a plurality of crystal grains having a layered structure in which a plurality of unit crystal cells made of a ferroelectric material are stacked to form one crystal phase; For at least 80% (volume / volume) of the crystal grains, the crystal axis along the stacking direction of the unit crystal cells is 50.7 ° with respect to the interface between the lower electrode and the ferroelectric thin film.
A ferroelectric element, which is oriented at an angle of not less than 58.7 °. 2. The ferroelectric element according to claim 1, wherein the angle of the orientation is 54.7 °. 3. A ferroelectric device comprising a lower electrode, a ferroelectric thin film, and an upper electrode laminated in this order, wherein the lower electrode has at least a crystal forming a surface in contact with the ferroelectric thin film, The ferroelectric thin film is oriented in a (111) plane, and includes a plurality of crystal grains having a layered structure in which a plurality of unit crystal cells made of a ferroelectric material are stacked to form one crystal phase; For at least 80% (volume / volume) of the crystal grains, the crystal axis along the stacking direction of the unit crystal cells is 31.3 ° with respect to the interface between the lower electrode and the ferroelectric thin film.
A ferroelectric element characterized by being oriented at an angle of not less than 39.3 °. 4. The ferroelectric device according to claim 3, wherein the angle of the orientation is 35.3 °. 5. The ferroelectric device according to claim 1, wherein said layered structure is a layered perovskite structure. 6. The ferroelectric device according to claim 1, wherein said ferroelectric material is represented by the following general formula (Formula 1). (AO) ²⁺ (B _y-1 C _y O _{3y + 1} ) ^2- (Chemical _formula 1) (where A is at least one element selected from Tl, Hg, Pb, Bi and rare earth elements; Is B
i is at least one element selected from Pb, Ca, Sr and Ba, and C is Ti, Nb, Ta, W, M
at least one of o, Fe, Co, Cr and Zr
And y is an integer from 2 to 5) 7. The ferroelectric device according to claim 1, wherein a crystal constituting a surface in contact with said ferroelectric thin film is made of Pt. 8. The ferroelectric element according to claim 1, wherein the crystal forming the surface in contact with the ferroelectric thin film is made of a first conductive oxide having a perovskite structure. Dielectric element. 9. The ferroelectric device according to claim 8, wherein said first conductive oxide is ReO ₃ , SrReO ₃ , BaReO ₃ , LaTiO ₃ , S
rVO ₃ , CaCrO ₃ , SrCrO ₃ , SrFeO ₃ , La _1-x
Sr _x CoO ₃ (0 <x <0.5), LaNiO ₃ , Ca
RuO ₃ , SrRuO ₃ , SrTiO ₃ , and BaP
A ferroelectric device, which is any one of bO ₃ and has a resistivity of 1 mΩ · cm or less. 10. The ferroelectric device according to claim 9, wherein the lower electrode is formed of a metal layer and a second conductive oxide, which is a single element oxide, stacked in this order. Layer and the first
And a layer made of a conductive oxide of the above. 11. The ferroelectric device according to claim 10, wherein said second conductive oxide is Ti, V, Eu, Cr, Mo, W, Ph, Os, Ir,
A ferroelectric element, which is an oxide of any one of Pt, Re, Ru, and Sn and has a resistivity of 1 mΩ · cm or less. 12. A semiconductor device comprising the ferroelectric element according to claim 1. 13. The semiconductor device according to claim 12, wherein said ferroelectric element is a capacitor having a field effect transistor structure.