Electric field-vibration radiation transducer with high displacement piezoelectric material and method for manufacturing same

Abstract

The present invention relates to an electric field-vibration radiation transducer with a high displacement piezoelectric material and a method for manufacturing the same, which has a high piezoelectric constant (d 33 =1,000~6,000pC / N), high dielectric constant (K3 T By applying high strain piezoelectric materials with low dielectric loss (tanδ<2%) together with a high strain coefficient (δ=6,000-15,000), excellent radiation characteristics can be realized in an electric field-vibration emitting transducer that is highly efficient and driven at a low voltage, and furthermore, manufacturing costs can be reduced by miniaturization. Therefore, the electric field-vibration emitting transducer can be applied to medical devices for promoting the transport of substances, chemical actions, and biological reactions, and for treating tumors in humans and animals.

Description

[Technical field]

[0001] The present invention relates to Electric Field and Vibration Generating (EFVG) Transducers with high displacement piezoelectric material and a method for manufacturing the same, and more particularly to a method for manufacturing the same with high piezoelectric constant (d 33 =1,000~6,000pC / N), high dielectric constant (K3 T The present invention relates to an electric field-vibration emitting transducer and a manufacturing method thereof, which can be used in medical devices for treating tumors in humans and animals by simultaneously generating an electric field and mechanical vibration by applying high strain piezoelectrics having a high strain index (T = 6,000-15,000) and low dielectric loss (tan δ<2%) and promoting the movement of substances, chemical action, and biological reaction using the generated electric field and mechanical vibration. [Background technology]

[0002] Electric field emission can be achieved by using a metal wire or by applying a voltage to a dielectric. In particular, the method of directly applying a voltage to a dielectric to emit an electric field can emit an electric field more effectively than the method of using a general metal plate.

[0003] Specifically, when a dielectric is placed between two metal plates, the density of the electric field between the two metal plates increases due to the polarization phenomenon of the dielectric, but when the space between the two metal plates is a vacuum, the density of the electric field between the two metal plates is simply proportional to the applied voltage because there is no polarization phenomenon.

[0004] Therefore, by utilizing the polarization phenomenon of dielectrics, the electric field between two metal plates becomes larger, and as a result, a larger electric field can be emitted. Such electric field emission is used in fields that control various phenomena such as material transfer, chemical reactions, and biological reactions, and is expected to be further expanded in the future, and is expected to be applied to medical devices, etc.

[0005] In general, a field emission transducer using a dielectric includes a dielectric element, an external electrode for applying an electric field to the dielectric element, and a voltage supplying device for applying a voltage to the external electrode. The dielectric element is electrically connected to the external electrode, and the external electrode is connected to a voltage supplying device to apply an electric signal to the dielectric element. In this case, the magnitude of the electric field emitted from the field emission transducer is generally proportional to the magnitude of the applied voltage and the dielectric constant of the dielectric. Therefore, the magnitude of the emitted electric field can be increased by using a material with a large dielectric constant.

[0006] Generally, among dielectric ceramic materials, ferroelectric BaTiO3, Pb(Zr,Ti)O3 (hereinafter referred to as "PZT"), Pb(Mg 1 / 3 Nb 2 / 3 )O3 (hereinafter referred to as "PMN"), and Pb(Mg 1 / 3 Nb 2 / 3 In the past, BaTiO3-PbTiO3 (hereinafter referred to as "PMN-PT") based polycrystalline ceramic materials have been mainly used. The BaTiO3, PZT, PMN and PMN-PT based polycrystalline ceramic materials have a large dielectric constant, are low cost, and have well-known manufacturing process technologies, and are used in a variety of application fields.

[0007] However, the dielectric / ferroelectric materials of BaTiO3, PZT, PMN and PMN-PT polycrystalline ceramic materials currently in use have the drawbacks of a dielectric constant of 5,000 or less and a dielectric loss (tan δ) of more than 2.0%. If the dielectric loss is large, heat generation is large when a voltage is applied, especially when an AC voltage is applied, and the physical properties of the dielectric are deteriorated, resulting in a decrease in the efficiency of the field emission transducer.

[0008] Heat generation also changes the ambient temperature, making it difficult to control chemical or biological reactions.

[0009] These limitations of dielectric ceramic materials limit the performance of field emission transducers, increase power consumption, and make the entire system larger, making it difficult to manufacture portable products.

[0010] Therefore, the performance of a field emission transducer depends on the performance of the dielectric, and therefore a dielectric or ferroelectric material with a high dielectric constant and low dielectric loss is required.

[0011] As a result, piezoelectric single crystals with a perovskite crystal structure ([A][B]O3) have a much higher dielectric constant (K3 T) and the piezoelectric constant (d 33 ) and at the same time low dielectric loss characteristics, suggesting the possibility of developing a field emission transducer using this material.

[0012] An example of the piezoelectric single crystal having the perovskite crystal structure is PMN-PT(Pb(Mg 1 / 3 Nb 2 / 3 )O3-PbTiO3), PZN-PT(Pb(Zn 1 / 3 Nb 2 / 3 )O3-PbTiO3), PInN-PT(Pb(In 1 / 2 Nb 1 / 2 )O3-PbTiO3), PYbN-PT(Pb(Yb 1 / 2 Nb 1 / 2 )O3-PbTiO3), PSN-PT(Pb(Sc 1 / 2 Nb 1 / 2)O3-PbTiO3), PMN-PInN-PT, PMN-PYbN-PT, and BiScO3-PbTiO3 (BS-PT). These piezoelectric single crystals exhibit congruent melting behavior during melting, and have been manufactured by the flux method, Bridgman method, and other methods.

[0013] In general, it is known that piezoelectric single crystals with a perovskite crystal structure have the highest dielectric and piezoelectric properties in the region near the phase boundary between the rhombohedral phase and the tetragonal phase, i.e., the morphotropic phase boundary (MPB).

[0014] However, piezoelectric single crystals with a perovskite crystal structure generally exhibit the best dielectric and piezoelectric properties when they have a rhombohedral phase, and so applications of rhombohedral phase piezoelectric single crystals are most active. However, the phase transition temperature (T RT ) below which the rhombohedral phase exhibits stable behavior. RT It can only be used in the following cases: RT When the phase transition temperature is low, the operating temperature of the rhombohedral phase piezoelectric single crystal is low, and the manufacturing temperature and operating temperature of the piezoelectric single crystal application parts are also T RT The phase transition temperature (T C , T RT ) and coercive electric field (E C If the dielectric constant is low, the piezoelectric single crystal is easily depoled under mechanical processing, stress, heat generation, and driving voltage, resulting in the loss of excellent dielectric and piezoelectric properties.

[0015] In addition, compared to piezoelectric polycrystalline ceramic materials, piezoelectric single crystals have a high piezoelectric constant (d 33 ≧1,000~2,000pC / N), but has a low coercive electric field (E C≦2~5kV / cm), it is prone to depoling, so its electrical stability is low and its practical use is limited. For this reason, methods have been proposed to increase the coercive electric field of piezoelectric single crystals, but the increase in the coercive electric field is accompanied by a deterioration of the piezoelectric properties, and it is pointed out that the effectiveness is still low.

[0016] Therefore, currently, research is being continuously conducted to simultaneously improve the mechanical properties of piezoelectric single crystals as well as the dielectric constant, piezoelectric constant, phase transition temperature, and coercive field. In particular, piezoelectric single crystals having compositions mainly composed of expensive elements such as Sc and In have a substantial obstacle to practical use due to the high manufacturing cost of the single crystals.

[0017] Patent Document 1 is an invention related to the Solid-state Single Crystal Growth (SSCG) Method, which, unlike conventional liquid-phase single crystal growth methods, does not use a melting process or special equipment, but rather uses a general, simple heat treatment process to control the abnormal grain growth that occurs in polycrystalline bodies, making it possible to produce single crystals of various compositions using the solid-phase single crystal growth method, thereby reducing the production costs of single crystals and presenting a single crystal growth method that can mass-produce single crystals in a highly reproducible and economical manner.

[0018] In addition, Patent Document 2 discloses a method for growing a high dielectric constant (K3 T ), high piezoelectric constant (d 33 , k 33 The present invention discloses a piezoelectric single crystal having improved mechanical properties together with a high phase transition temperature (Curie temperature, Tc) and a high coercive electric field (Ec). The piezoelectric single crystal is manufactured by a solid phase single crystal growth method suitable for mass production of single crystals, and a single crystal composition that does not contain expensive raw materials is developed, realizing commercialization of piezoelectric single crystals. Piezoelectric application parts and dielectric application parts using piezoelectric single crystals with excellent properties can be manufactured and used over a wide temperature range.

[0019] Therefore, the inventors have endeavored to improve the performance of the field emission transducer, and as a result, T ), high piezoelectric constant (d 33 , k 33 By applying high strain piezoelectrics with low dielectric loss together with the above, not only an electric field but also mechanical vibration can be generated at the same time, and a new electric field-vibration radiation transducer can be developed using the generated electric field and mechanical vibration. The present invention has been completed by confirming the characteristics of high efficiency, low voltage operation, and low heat generation. [Prior art documents] [Patent documents]

[0020] [Patent Document 1] Korean Patent No. 0564092 (Announced 2006.03.27) [Patent Document 2] Korean Patent No. 0743614 (announced on 30 July 2007) Summary of the Invention [Problem to be solved by the invention]

[0021] It is an object of the present invention to provide an electric field-vibration emitting transducer that can simultaneously emit and control electric fields and mechanical vibrations.

[0022] Another object of the present invention is to provide a method for producing an electric field-vibration radiation transducer using a piezoelectric single crystal or a polymer-piezoelectric composite containing the piezoelectric single crystal as a high displacement piezoelectric material. [Means for solving the problem]

[0023] In order to achieve the above object, the present invention provides a piezoelectric material having a perovskite crystal structure ([A][B]O3) and an electrode formed on at least one surface of the piezoelectric material, The piezoelectric constant (d 33) is 1,000~6,000pC / N, The dielectric constant (K T ) is between 6,000 and 15,000, and By satisfying a dielectric loss of 2% or less for the piezoelectric material, an electric field-vibration emitting transducer is provided that simultaneously emits an electric field and mechanical vibration.

[0024] In the electric field-vibration radiation transducer of the present invention, the electrodes are formed on only one surface of the piezoelectric material, or when formed on both surfaces, the electrodes are asymmetrically formed by making the material, shape or area of ​​the electrodes different from each other, and the electrodes are made of any one material selected from the group consisting of conductive metals, carbon and conductive ceramics.

[0025] The electric field-vibration radiation transducer of the present invention uses a piezoelectric single crystal or a polymer-piezoelectric composite containing the piezoelectric single crystal as the piezoelectric material.

[0026] The piezoelectric single crystal is grown by a solid phase single crystal growth method, and more specifically, has a composition formula of Chemical Formula 1 below.

[0027] chemical formula 1 [A 1-(a+1.5b) B a C b ][(MN) 1-x-y (L) y Ti x ]O 3-z

[0028] In the above formula, A is at least one selected from the group consisting of Pb, Sr, Ba and Bi; B is at least one selected from the group consisting of Ba, Ca, Co, Fe, Ni, Sn, and Sr; C is at least one selected from the group consisting of Co, Fe, Bi, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu; L is selected from Zr or Hf, either alone or in mixture; M is at least one selected from the group consisting of Ce, Co, Fe, In, Mg, Mn, Ni, Sc, Yb, and Zn; N is at least one selected from the group consisting of Nb, Sb, Ta, and W; 0≦a≦0.10, 0≦b≦0.05, 0.05≦x≦0.58, 0.05≦y≦0.62, and 0≦z≦0.02.

[0029] The piezoelectric single crystal satisfies 0.01≦a≦0.10 and 0.01≦b≦0.05 in the formula, and in particular a / b≧2 in the formula.

[0030] Moreover, the piezoelectric single crystal preferably satisfies 0.10≦x≦0.58 and 0.10≦y≦0.62.

[0031] When L is a mixed form, the piezoelectric single crystal has a composition formula of Chemical Formula 2 or Chemical Formula 3.

[0032] chemical formula 2 [A 1-(a+1.5b) B a C b ][(MN) 1-x-y (Zr 1-w、 Hf w ) y Ti x ]O3

[0033] chemical formula 3 [A 1-(a+1.5b) B a C b ][(MN) 1-x-y (Zr 1-w、 Hf w ) y Ti x ]O 3-z

[0034] In the above formula, A, B, C, M, N, a, b, x, y and z are the same as those in Chemical Formula 1, with the proviso that 0.01≦w≦0.20.

[0035] In the present invention, the composition of the piezoelectric single crystal may further contain a reinforcing second phase (P) at a volume ratio of 0.1 to 20%, and the reinforcing second phase P is a metal phase, an oxide phase, or pores.

[0036] The reinforcing second phase P is at least one selected from the group consisting of Au, Ag, Ir, Pt, Pd, Rh, MgO, ZrO2, and pores, and the reinforcing second phase P is uniformly distributed in the form of particles in the piezoelectric single crystal, or regularly distributed in a certain pattern.

[0037] Additionally, the electric field-vibration emitting transducer of the present invention may use a polymer-piezoelectric composite as the piezoelectric material to provide flexibility.

[0038] The polymer-piezoelectric composite may contain a piezoelectric polycrystal or a piezoelectric single crystal in a polymer matrix, and specifically, may contain 10 to 80 volume % of a polymer matrix.

[0039] Specifically, the polymer-piezoelectric composite has a 1-3 type or 2-2 type composite structure in which a rod-shaped piezoelectric material is embedded in a polymer matrix, and the piezoelectric composite is a mixture of a piezoelectric single crystal and a piezoelectric polycrystalline ceramic.

[0040] The electric field-vibration radiating transducer emits an electric field having a frequency of 0.01 Hz to 500 kHz and an intensity of the electric field of 0.01 to 100 V / cm.

[0041] Moreover, the frequency of the emitted mechanical vibration is 0.1 Hz to 3 MHz, and the magnitude of the mechanical vibration is a maximum of 1%.

[0042] In the electric field-vibration radiation transducer of the present invention, the piezoelectric material may have surface irregularities formed by pores or grooves (grooves, channels, etc.) on the surface.

[0043] Furthermore, the present invention provides a method for manufacturing an electric field-vibration radiation transducer, comprising the steps of: processing a piezoelectric material having a perovskite crystal structure ([A][B]O3) to a thickness of 0.1 to 100 mm; forming external electrodes on both sides of the piezoelectric material; poling the piezoelectric material by applying a voltage to the external electrodes to maximize the dielectric and piezoelectric properties of the piezoelectric material; and removing part or all of one of the external electrodes formed on both sides to form an asymmetric structure.

[0044] The piezoelectric material is a piezoelectric single crystal having a perovskite crystal structure ([A][B]O3), or a polymer-piezoelectric composite containing the piezoelectric single crystal. Effect of the Invention

[0045] The electric field-vibration radiation transducer according to the present invention has a high piezoelectric constant (d 33 =1,000~6,000pC / N), high dielectric constant (K3 T By including a high-displacement piezoelectric material having a low dielectric loss (tan δ<2%) together with a dielectric constant of 0.05% (tan δ=6,000-15,000), it is possible to provide an electric field-vibration emitting transducer that retains high characteristics and simultaneously generates an electric field and mechanical vibration.

[0046] The piezoelectric single crystal having piezoelectric properties used in the present invention can retain high dielectric constants and piezoelectric constants by the solid phase single crystal growth method and can be mass-produced at low cost, thereby facilitating the transfer of substances, chemical actions, and biological reactions, and can improve the performance and satisfy the cost competitiveness of medical devices for treating tumors in humans and animals. [Brief description of the drawings]

[0047] [Figure 1] 1 is a cross-sectional schematic diagram of an electric field-vibration radiation transducer of the present invention. [Diagram 2] FIG. 1 is a diagram showing the case where the electric field-vibration emitting transducer of the present invention is applied as a medical device. [Diagram 3]1 shows the results of bending evaluation of the polymer-piezoelectric composite of the present invention. [Figure 4] FIG. 2 is a schematic diagram of the polymer-piezoelectric composite structure. [Diagram 5] 1 is an image of the 1-3 type complex structure of the present invention. [Figure 6] 1 shows a step-by-step process for manufacturing an electric field-vibration radiation transducer using the polymer-piezoelectric composite. [Figure 7] 1 shows the strength of the electric field induced by applying a voltage to an electric field-vibration radiation transducer using a piezoelectric single crystal having a composition of [Pb0.965Sr0.02La0.01][(Mg1 / 3Nb2 / 3)0.4Zr0.25Ti0.35]O3 according to the present invention. [Figure 8] 8 shows the magnitude of mechanical vibration caused by application of a voltage to the electric field-vibration emitting transducer of FIG. 7. [Figure 9] This shows the strength of the electric field induced by applying a voltage to an electric field-vibration radiation transducer using a piezoelectric single crystal having a composition of [Pb0.965Sr0.02Sm0.01][(Mg1 / 3Nb2 / 3)0.25(Ni1 / 3Nb2 / 3)0.10Zr0.30Ti0.35]O3 of the present invention. [Figure 10] 10 shows the magnitude of mechanical vibration caused by application of a voltage to the electric field-vibration emitting transducer of FIG. 9. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0048] The present invention will be described in detail below.

[0049] The present invention provides an electric field-vibration radiation transducer including a piezoelectric material having a perovskite crystal structure ([A][B]O3) and an electrode formed on at least one surface of the piezoelectric material.

[0050] In the electric field-vibration radiation transducer, the piezoelectric material has: (1) a piezoelectric constant (d 33 ) 1,000~6,000pC / N, (2) Dielectric constant (K3 T) 6,000 to 15,000, and (3) a dielectric loss of 2% or less, and an electric field-vibration emitting transducer can be manufactured by simultaneously emitting an electric field and mechanical vibration when a voltage is applied, and the frequency, magnitude, and direction of the emitted electric field and mechanical vibration can be simultaneously controlled.

[0051] The frequency of the emitted electric field is 0.01 to 500 kHz, and the intensity of the electric field is 0.01 to 100 V / cm.

[0052] The frequency of the emitted mechanical vibration is 0.1 Hz to 3 MHz, and the magnitude of the mechanical vibration is a maximum of 1%.

[0053] In the electric field-vibration radiation transducer of the present invention, the electrodes are formed on only one surface of the piezoelectric material, or when formed on both surfaces, the electrodes are asymmetrically formed by making the material, shape or area of ​​the electrodes different. In this case, the electrodes can be made of any one material selected from the group consisting of conductive metals, carbon and conductive ceramics.

[0054] FIG. 1 shows a schematic cross-sectional view of the electric field-vibration emitting transducer of the present invention. In a preferred embodiment, the electric field-vibration emitting transducer has an asymmetric structure in which an electrode 12 is formed on only one side of a piezoelectric material 11. When this is applied to a medical device, the surface of the piezoelectric material is directly in contact with the skin, and when a voltage is applied, an electric field and mechanical vibration are simultaneously emitted, thereby providing a therapeutic effect on a target tumor.

[0055] It is preferable to artificially provide pores and grooves (channels, etc.) on the surface of the piezoelectric material to form surface irregularities. The surface irregularities can be formed by using pores inside the piezoelectric material or by selecting one or more of mechanical and chemical processing. The shape of the surface irregularities of the piezoelectric material locally affects the distribution of electric field and vibration. By changing the shape of the surface irregularities, the local distribution of electric field and vibration can be controlled and the effect can be maximized.

[0056] In the electric field-vibration radiation transducer of the present invention, the piezoelectric material BaTiO3, PZT, PMN and PMN-PT polycrystalline ceramic materials have a piezoelectric constant (d 33 ) is 600pC / N or less, so at low applied voltages, the displacement increases proportionally, but above a certain applied voltage (or electric field), the displacement shows nonlinear behavior where it cannot increase any further, and the maximum displacement is generally 0.3% or less. Therefore, when polycrystalline ceramic materials are used alone, a maximum displacement of 1% cannot be generated below the voltage allowable for each application component, making it difficult to generate sufficient mechanical vibration required for practical applications.

[0057] In particular, the magnitude of mechanical vibration that can be generated is further reduced due to the structure in which electrodes are formed only on one side of the dielectric in the field emission transducer. Therefore, the sole use of BaTiO3, PZT, PMN and PMN-PT polycrystalline ceramic materials as piezoelectric materials in the field-vibration emission transducer of the present invention is excluded.

[0058] In addition, even in the case of ordinary dielectric ceramics with a high dielectric constant, when an AC voltage is applied, heat generation increases due to a large dielectric loss, resulting in a decrease in the efficiency of the field emission transducer, and therefore, the practical application value is low.

[0059] From the above, in the electric field-vibration radiation transducer of the present invention, (1) the piezoelectric constant (d 33 ) is 1,000 to 6,000 pC / N, (2) the dielectric constant (K3 T The essential conditions for the piezoelectric material are that (1) the dielectric constant is 6,000 to 15,000, and the piezoelectric properties are excellent, and (2) the dielectric loss of the piezoelectric material is low, at 2% or less. By applying a high-displacement piezoelectric material that satisfies the essential conditions, a novel electric field-vibration radiation transducer having characteristics of high efficiency, low drive voltage, and low heat generation can be realized.

[0060] The piezoelectric material used in the electric field-vibration radiation transducer of the present invention is a piezoelectric single crystal having a perovskite crystal structure ([A][B]O3), or a polymer-piezoelectric composite containing the piezoelectric single crystal. In the case of the piezoelectric single crystal, as the applied voltage increases, the displacement (or vibration) increases proportionally, thereby making it possible to achieve a maximum displacement of 1%.

[0061] Each material will be described in detail below.

[0062] 1. Piezoelectric single crystal The piezoelectric single crystal used in the electric field-vibration radiation transducer of the present invention has the following characteristics: (1) piezoelectric constant (d 33 ) 1,000~6,000pC / N, (2) Dielectric constant (K3 T ) 6,000 to 15,000, and (2) a piezoelectric property that simultaneously exhibits a dielectric loss of 2% or less.

[0063] A piezoelectric single crystal that satisfies these characteristics is a piezoelectric single crystal grown by a solid phase single crystal growth method, and more specifically, is a piezoelectric single crystal having a composition formula of a perovskite structure ([A][B]O3) represented by the following chemical formula 1.

[0064] chemical formula 1 [A 1-(a+1.5b) B a C b ][(MN) 1-x-y (L) y Ti x ]O 3-z

[0065] In the above formula, A is at least one selected from the group consisting of Pb, Sr, Ba and Bi; B is at least one selected from the group consisting of Ba, Ca, Co, Fe, Ni, Sn, and Sr; C is at least one selected from the group consisting of Co, Fe, Bi, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu; L is selected from Zr or Hf, either alone or in mixture form. M is at least one selected from the group consisting of Ce, Co, Fe, In, Mg, Mn, Ni, Sc, Yb, and Zn; N is at least one selected from the group consisting of Nb, Sb, Ta, and W; 0≦a≦0.10, 0≦b≦0.05, 0.05≦x≦0.58, 0.05≦y≦0.62, and 0≦z≦0.02.

[0066] Specifically, it is a piezoelectric single crystal (a=0, b=0) with a perovskite crystal structure ([A][B]O3) containing zirconium (Zr). (1-a-b) Sr a Ba b ][((Mg,Zn) 1 / 3 Nb 2 / 3 ) (1-x-y) Ti x Zr y ]O3, [Pb][((Mg 1-a Zinc a ) 1 / 3 Nb 2 / 3 ) (1-x-y) Ti x Zr y ]O3, [Pb][(Mg 1 / 3 Nb 2 / 3 ) (1-x-y) Ti x Zr y ]O3, [Ba x Bi (1-x) ][Fe (1-x) Ti (x-y) Zr y ]O3 is one example.

[0067] The present invention also includes a piezoelectric single crystal that can improve the piezoelectric properties uniformly without a composition gradient even if it has a complex chemical composition by a solid phase single crystal growth method. Specifically, in a perovskite crystal structure ([A][B]O3), the complex composition of the [A] site ions (a≠0, b≠0) provides a high dielectric constant (K3 T ), high piezoelectric constant (d 33 , k 33 ), high phase transition temperature (T C , TRT ) and high coercive electric field (E C ) to improve the dielectric properties.

[0068] Therefore, in the piezoelectric single crystal having the composition formula of Chemical Formula 1, the composite composition of the [A] site ions is specifically described as follows: 1-(a+1.5b) B a C b The composition of A may include lead-containing or lead-free elements. In the embodiments of the present invention, the description will be limited to a lead-containing piezoelectric single crystal in which A is Pb, but the present invention is not limited thereto.

[0069] In the [A] site ion, the B composition is a divalent metal element, preferably at least one selected from the group consisting of Ba, Ca, Co, Fe, Ni, Sn, and Sr, and the C composition can be any trivalent metal element.

[0070] Preferably, it is at least one selected from the group consisting of Co, Fe, Bi, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, and more preferably, the lanthanum-based element is used in a form of one or a mixture of two kinds.

[0071] In the examples of the present invention, the composition of C in the [A] site ions is described as a single composition containing Sm or a mixed composition of two or more kinds, but the present invention is not limited to this.

[0072] In the piezoelectric single crystal having the composition formula of Chemical Formula 1 or Chemical Formula 2, in the composite composition of the [A] site ions, [A 1-(a+1.5b ) B a C b The composition of [A] is an essential condition for realizing the desired physical properties, and when A is a lead-containing or lead-free piezoelectric single crystal, it is characterized by being composed of a combination of a divalent metal element and a trivalent metal element.

[0073] In the above formula, 0.01≦a≦0.10 and 0.01≦b≦0.05 are satisfied, and in particular, a / b≧2. If a is less than 0.01, there is a problem that the perovskite phase is unstable, and if a exceeds 0.10, the phase transition temperature is too low for practical use, which is not preferable.

[0074] In addition, if the requirement of a / b≧2 is not satisfied, the dielectric and piezoelectric properties will not be maximized or the single crystal growth will be restricted, which is undesirable. In this regard, in the piezoelectric single crystal having the composition formula of Chemical Formula 1, the composite composition of [A] site ions can achieve a superior dielectric constant compared to the case where the composite composition is composed of a single metal trivalent element or a single metal divalent element.

[0075] In the formula 1, x is preferably 0.05≦x≦0.58, more preferably 0.10≦x≦0.58. The reason is that when x is less than 0.05, the phase transition temperature (Tc and TRT) and the piezoelectric constant (d 33 , k 33 ) or coercive field (Ec) is low and x is greater than 0.58, the dielectric constant (K3 T ), piezoelectric constant (d 33 , k 33 ) or the phase transition temperature (TRT) is low. Note that y preferably satisfies 0.050≦y≦0.62, and more preferably 0.10≦y≦0.62. The reason is that when y is less than 0.05, the phase transition temperature (Tc and TRT), the piezoelectric constant (d 33 , k 33 ) or coercive field (Ec) is low and exceeds 0.62, the dielectric constant (K3 T ) or the piezoelectric constant (d 33 , k 33 ) is low.

[0076] The piezoelectric single crystal having the composition formula of Chemical Formula 1 of the present invention contains a tetravalent metal element in the [B] site ion in the perovskite crystal structure ([A][B]O3), and in particular, the L composition is limited to a single or mixed form selected from Zr and Hf.

[0077] In the case of the mixed form, a piezoelectric single crystal having a composition formula of the following Chemical Formula 2 or Chemical Formula 3 is provided.

[0078] chemical formula 2 [A 1-(a+1.5b) BaC b ][(MN) 1-x-y (Zr 1-w、 Hf w ) y Ti x ]O3

[0079] chemical formula 3 [A1-(a+1.5b)B a C b ][(MN) 1-x-y (Zr 1-w、 Hf w ) y Ti x ]O 3-z

[0080] In the above formula, A, B, C, M, and N, as well as a, b, x, y, and z are the same as those in Chemical Formula 1, with the proviso that 0.01≦w≦0.20.

[0081] In this case, if w is less than 0.01, the dielectric and piezoelectric properties will not be maximized, and if it exceeds 0.20, the dielectric and piezoelectric properties will be rapidly degraded, which is undesirable.

[0082] The piezoelectric single crystal having the composition formula of Chemical Formula 2 or Chemical Formula 3 has a Curie temperature (Tc) of 180°C or higher and a phase transition temperature (Tc) between rhombohedral phase and tetragonal phase (Tc) of 180°C or higher by combining a composite composition of [A] site ions and a composition of [B] site ions in a perovskite crystal structure ([A][B]O3). RT ) is 100°C or higher. If the Curie temperature is less than 180°C, the coercive electric field (Ec) is 5 kV / cm or higher, or the phase transition temperature (T RT) is difficult to raise above 100°C.

[0083] In addition, the piezoelectric single crystal having the composition formula of Chemical Formula 1 of the present invention is characterized in that the oxygen vacancy of the [O] site in the perovskite crystal structure ([A][B]O3) is controlled to 0≦z≦0.02. In this case, if the z exceeds 0.02, there is a problem that the dielectric properties and piezoelectric properties are rapidly deteriorated, which is not preferable.

[0084] When oxygen vacancies are induced within this range, the coercive electric field and the internal electric field are effectively increased, and the stability of the piezoelectric single crystal is improved under electric field driving and mechanical load conditions, thereby maximizing the piezoelectric properties and increasing the stability.

[0085] The piezoelectric single crystal having the composition formula of Chemical Formula 1 according to the present invention has an electromechanical coupling coefficient (k 33 ) is 0.85 or more, and if the electromechanical coupling coefficient is less than 0.85, the characteristics will be similar to those of piezoelectric polycrystalline ceramics, and the energy conversion efficiency will decrease, which is not preferable.

[0086] The piezoelectric single crystal of the present invention has a coercive electric field (E C If the coercive electric field is less than 4 kV / cm, there is a problem that poling is easily removed during processing of the piezoelectric single crystal or during manufacture or use of piezoelectric single crystal application parts.

[0087] Furthermore, the piezoelectric single crystal having the composition formula of Chemical Formula 1 of the present invention has a composition gradient of 0.2 to 0.5 mol % inside the single crystal, so that a uniform single crystal can be provided.

[0088] Lead zirconate (PbZrO3) not only has a high phase transition temperature of 230°C, but also has the effect of making the MPB more perpendicular to the temperature axis, so that it maintains a high Curie temperature and has a high phase transition temperature (T RT ) can be obtained, resulting in high Tc and T RT It is possible to develop compositions that simultaneously

[0089] This is because even if lead zirconate is added to the composition of a conventional piezoelectric single crystal, the phase transition temperature rises in proportion to the content of lead zirconate. Therefore, a piezoelectric single crystal having a perovskite crystal structure containing zirconium (Zr) or lead zirconate can overcome the problems of existing piezoelectric single crystals. In addition, since zirconia (ZrO2) or lead zirconate is used as the main component of existing piezoelectric polycrystalline materials and is an inexpensive raw material, the object of the present invention can be achieved without increasing the raw material cost of the single crystal.

[0090] On the other hand, perovskite type piezoelectric single crystals containing lead zirconate do not show congruent melting behavior during melting, but show non-eutectic melting behavior, unlike PMN-PT, PZN-PT, etc. Therefore, when they show non-eutectic behavior, they are separated into liquid phase and solid phase zirconia (solid phase ZrO2) during solid phase melting, and the solid phase zirconia particles in the liquid phase hinder single crystal growth, so they cannot be manufactured by the flux method or the Briemann method, which are general single crystal growth methods that use a melting process.

[0091] In addition, in the general single crystal growth method using a melting process, it is difficult to produce a single crystal containing a reinforcing second phase, and no such method has been reported yet. This is because the reinforcing second phase is chemically unstable and reacts with the liquid phase above the melting temperature, so the independent shape of the second phase cannot be maintained and disappears. In addition, the second phase and the liquid phase are separated due to the density difference between the second phase and the liquid phase in the liquid phase, making it difficult to produce a single crystal containing a second phase, and furthermore, it is impossible to adjust the volume fraction, size, shape, arrangement, distribution, etc. of the reinforcing second phase in the single crystal.

[0092] Thus, the present invention produces piezoelectric single crystals containing a reinforcing second phase using a solid phase single crystal growth method that does not use a melting step.

[0093] The reinforcing second phase may be at least one selected from the group consisting of a metal phase (e.g., Au, Ag, Ir, Pt, Pd, or Rh), an oxide phase (e.g., MgO or ZrO2), or pores.

[0094] In addition, single crystal growth occurs in the polycrystalline body containing the reinforcing second phase, and the volume fraction, size, shape, arrangement, and distribution of the reinforcing second phase do not change during the single crystal growth. Therefore, in the process of producing a polycrystalline body containing a reinforcing second phase, if the volume fraction, size, shape, arrangement, and distribution of the reinforcing second phase in the polycrystalline body is adjusted and a single crystal is grown, a single crystal containing a reinforcing second phase of a desired shape, i.e., a second phase-reinforced single crystal, can be produced. The reinforcing second phase (P) is uniformly distributed in the form of particles or regularly distributed in a predetermined pattern, and this realizes the characteristic that the dielectric, piezoelectric, and mechanical properties of the piezoelectric single crystal are improved depending on the distribution form of the second phase.

[0095] Therefore, according to the present invention, by providing a perovskite-type piezoelectric single crystal containing lead zirconate by a solid phase single crystal growth method, no special equipment is required, and the manufacturing cost of the single crystal can be reduced by a general heat treatment process, allowing mass production at a lower cost than the conventional flux method or Breemann method.

[0096] In addition, the present invention uses a solid-phase single crystal growth method to grow piezoelectric single crystals uniformly, even when the composition of the [A] site ions and the combination of the [B] site ions in the perovskite crystal structure ([A][B]O3) containing lead zirconate are complex, and the dielectric constant (K3 T =6,000~15,000), piezoelectric constant (d 33 = 1,000-6,000 pC / N) and dielectric loss (tan δ < 2%) are significantly improved compared to conventional piezoelectric single crystals.

[0097] An electric field-vibration emitting transducer using a piezoelectric single crystal having the above dielectric and piezoelectric properties as a dielectric material radiates an electric field and mechanical vibration simultaneously by adjusting the size and shape of the piezoelectric material and the frequency and strength of the input voltage, where (1) the frequency of the radiated electric field is 0.01Hz to 500kHz, the strength of the radiated electric field is 0.01V / cm to 100V / cm, and (2) the frequency of the radiated mechanical vibration is 0.1Hz to 3MHz, and the magnitude of the radiated mechanical vibration satisfies a maximum range of 1%.

[0098] 2. Polymer-Piezoelectric Composites FIG. 2 shows the application of the electric field-vibration emitting transducer of the present invention as a medical device.

[0099] The electric field-vibration radiation transducer 10 of the present invention includes a dielectric material 11 having dielectric properties, an external electrode 12 for applying an electric field to the dielectric material, and a voltage supply device 20 for applying a voltage to the external electrode. The dielectric material 11 is electrically connected to the external electrode 12, and the external electrode is connected to the voltage supply device 20 to apply an electric signal to the dielectric material. At this time, a plurality of the electric field-vibration radiation transducers may be attached to a body part 30 such as the head or skin, or may be attached to a body part adjacent to a target tumor.

[0100] The high piezoelectric constant (d 33 =1,000~6,000pC / N) and a high dielectric constant (K3 T Due to its dielectric properties of tangent length (tanδ<2%) and low dielectric loss (tanδ<6,000~15,000), it is possible to maximize the therapeutic effect by simultaneously emitting electric field and mechanical vibration when voltage is applied, and a massage effect can be provided by mechanical vibration. In this case, it must be applied to a curved surface rather than a flat surface, which requires the flexibility of the electric field-vibration emitting transducer.

[0101] Therefore, in the electric field-vibration radiation transducer of the present invention, by using a polymer-piezoelectric composite as the piezoelectric material, it is possible to impart flexibility to the electric field-vibration radiation transducer.

[0102] The polymer-piezoelectric composite includes 10-80 volume percent of a polymer matrix, which may be a commercial product of epoxy material (Epotek Epoxies 301 and 301-2), which has a lower viscosity than water and therefore naturally penetrates into cracks and gaps, cures with or without the application of heat, and can provide strong bonding strength, a property that also applies to glass, ceramics, quartz, metals, and most plastics. Thus, the use of a polymer in the polymer-piezoelectric composite can provide flexibility through strong bonding.

[0103] The polymer-piezoelectric composite has a 1-3 type or 2-2 type composite structure in which a rod-shaped piezoelectric material is embedded in a polymer matrix, and the piezoelectric composite can reduce the amount of piezoelectric single crystal used and be cost competitive by combining a piezoelectric polycrystalline ceramic material with a piezoelectric single crystal that satisfies the piezoelectric properties.

[0104] Here, the materials to be composited with the piezoelectric single crystal of the present invention may include not only BaTiO3, PZT, PMN and PMN-PT based polycrystalline ceramics, but also known piezoelectric single crystals having lower performance than the piezoelectric single crystal of the present invention.

[0105] For example, it has high dielectric and piezoelectric properties (K3 T >4,000, d 33 >1,400pC / N, k 33 >0.85), while also exhibiting a low phase transition temperature (T C , T RT ), low coercive field (E C ) and brittleness. 1 / 3 Nb 2 / 3 )O3-PbTiO3), PZN-PT(Pb(Zn 1 / 3 Nb 2 / 3 )O3-PbTiO3), PInN-PT(Pb(In 1 / 2 Nb 1 / 2 )O3-PbTiO3), PYbN-PT(Pb(Yb 1 / 2 Nb 1 / 2 )O3-PbTiO3), PSN-PT(Pb(Sc 1 / 2 Nb 1 / 2 )O3-PbTiO3), PMN-PInN-PT, PMN-PYbN-PT, and BiScO3-PbTiO3 (BS-PT).

[0106] FIG. 3 shows the flexibility of the polymer-piezoelectric composite according to the present invention as a result of bending evaluation, and FIG. 4 is a schematic diagram of the structure of the polymer-piezoelectric composite 110, which is a composite (type 1-3 composite) structure in which rod-shaped piezoelectric material 112 cut from a single crystal is embedded in a polymer matrix 111.

[0107] FIG. 5 is a photograph of a 1-3 type composite structure according to the present invention, showing the top and side views on the left side. As shown in the photo, polycrystalline ceramic is cut horizontally and vertically, and then, as shown in the photo on the right, a polymer is filled into the single crystal that grows after the cutting and hardened to complete the process. This method is more economical and advantageous for mass production than directly cutting a single crystal.

[0108] FIG. 6 shows a step-by-step process for fabricating an electric field-vibration radiation transducer using the polymer-piezoelectric composite.

[0109] Furthermore, the present invention provides a method for manufacturing an electric field-vibration radiation transducer, comprising the steps of: processing a piezoelectric material having a perovskite crystal structure ([A][B]O3) to a thickness of 0.1 to 100 mm; forming external electrodes on both sides of the piezoelectric material; poling the piezoelectric material by applying a voltage to the external electrodes to maximize the dielectric and piezoelectric properties of the piezoelectric material; and removing part or all of one of the external electrodes formed on both sides to form an asymmetric structure.

[0110] The piezoelectric material may be a piezoelectric single crystal having a perovskite crystal structure ([A][B]O3), or a polymer-piezoelectric composite containing the piezoelectric single crystal. As this is the same as above, detailed description will be omitted.

[0111] The thickness of the piezoelectric material during processing is determined by the magnitude and frequency of vibration, and is preferably 0.1 to 100 mm. In this case, if the thickness is less than 0.1 mm, the magnitude of the electric field and vibration is too small, limiting the actual effect, and if the thickness is more than 100 mm, the magnitude of the voltage inducing the electric field and vibration is too large, limiting the actual use.

[0112] The electric field-vibration emitting transducer manufactured by the manufacturing method includes: (1) The frequency of the radiated electric field is 0.01 Hz to 500 kHz, and the strength of the radiated electric field is 0.01 V / cm to 100 V / cm; (2) The frequency of the radiated mechanical vibration is between 0.1 Hz and 3 MHz, and the magnitude of the radiated mechanical vibration satisfies a maximum range of 1%.

[0113] The frequency and magnitude of the mechanical vibration radiated by the electric field-to-vibration radiating transducer can be controlled by utilizing the size and shape of the piezoelectric material, as well as by adjusting the frequency and magnitude of the input voltage.

[0114] The electric field-vibration emitting transducer described above uses a high-displacement piezoelectric material, which generates mechanical deformation and vibration when a voltage is applied to the piezoelectric material. The electric field and mechanical vibration are used to promote the movement of substances, chemical reactions, and biological reactions, and are also applicable to medical devices for treating tumors in humans and animals.

[0115] In particular, when the electric field-vibration emitting transducer is applied as a medical device, it can be flexibly attached to areas with a lot of bending, such as the skin or the head, and after being attached to the skin or the head, it is useful for the massage effect due to mechanical vibration and skin breathing. EXAMPLES

[0116] The present invention will now be described in more detail with reference to examples.

[0117] These examples are presented to more specifically explain the present invention, and the scope of the present invention is not limited to these examples.

[0118] <Example 1> Manufacturing of electric field-vibration radiation transducer using piezoelectric single crystal 1 [Pb][(Mg 1 / 3 Nb 2 / 3 ) 0.4 Zr 0.26 Ti 0.34]O3 composition was prepared. In addition, an excess amount of MgO was added during the powder synthesis process to contain 2 volume % of MgO second phase and pore-strengthening phase inside the prepared single crystal. The piezoelectric constant, dielectric constant and dielectric loss characteristics of the prepared piezoelectric single crystal were evaluated. As a result, the piezoelectric constant (d 33 ) 2,007 [pC / N], dielectric constant 6,560 and dielectric loss (tan δ) 0.9%.

[0119] The piezoelectric single crystal thus produced was cut into a (001) plane, and silver paste electrodes were applied to both sides. After poling, the Ag electrode on one side was removed and the crystal was cut to produce a plate-shaped electric field-vibration radiation transducer having a size of 20 (L) x 20 (L) x 1 (T) mm.

[0120] For the manufactured electric field-vibration radiating transducer, the intensity (magnitude) of the radiated electric field and the displacement of the mechanical vibration were measured and are shown in Table 1 below.

[0121] [Table 1]

[0122] From the above results, [Pb][(Mg 1 / 3 Nb 2 / 3 ) 0.4 Zr 0.26 Ti 0.34 An electric field-vibration radiation transducer using a piezoelectric single crystal with the composition ]O3 induced an electric field and displacement (vibration) at levels suitable for practical applications.

[0123] <Example 2> Manufacturing of electric field-vibration radiation transducer using piezoelectric single crystal 2 [Pb 0.965 Sr 0.02 La 0.01 ][(Mg 1 / 3 Nb 2 / 3 ) 0.4 Zr 0.25 Ti 0.35An electric field-vibration radiation transducer was manufactured in the same manner as in Example 1, except that a piezoelectric single crystal having a composition of ]O3 was manufactured and used.

[0124] At this time, the above [Pb 0.965 Sr 0.02 La 0.01 ][(Mg 1 / 3 Nb 2 / 3 ) 0.4 Zr 0.25 Ti 0.35 The piezoelectric constant (d 33 ) was 2,650 [pC / N], the dielectric constant was 8,773, and the dielectric loss (tan δ) was 0.5%.

[0125] Figure 7 shows the [Pb 0.965 Sr 0.02 La 0.01 ][(Mg 1 / 3 Nb 2 / 3 ) 0.4 Zr 0.25 Ti 0.35 ]O3, and Figure 8 shows the magnitude of the mechanical vibration when a voltage is applied to the same electric field-vibration emitting transducer as in Figure 7.

[0126] As a result, [Pb 0.965 Sr 0.02 La 0.01 ][(Mg 1 / 3 Nb 2 / 3 ) 0.4 Zr 0.25 Ti 0.35 The strength (magnitude) of the radiated electric field and the displacement of the mechanical vibration were measured for an electric field-vibration radiation transducer using a piezoelectric single crystal with the composition ]O3, and it was confirmed that an electric field and displacement (vibration) at a level suitable for practical application could be induced.

[0127] <Example 3> Manufacturing of electric field-vibration radiation transducer using piezoelectric single crystal 3 [Pb 0.965 Sr 0.02 Sm 0.01[(Mg 1 / 3 Nb 2 / 3 ) 0.25 (Ni 1 / 3 Nb 2 / 3 ) 0.10 Zr 0.30 Ti 0.35 O3 piezoelectric single crystal with the composition was manufactured. Also, during single crystal growth, pores on the polycrystalline matrix were captured in the single crystal, and the manufactured single crystal contained about 1.5% by volume of pore-strengthened phase. The piezoelectric constant (d 33 ) of the manufactured piezoelectric single crystal was 4,457 [pC / N], the dielectric constant was 14,678, and the dielectric loss (tanδ) was 1.0%.

[0128] The manufactured piezoelectric single crystal was cut on the (001) plane, gold (Au) electrodes were formed on both sides by a sputtering process, after poling, the Au electrode on one side was removed and cut to manufacture a plate-shaped [20(L)×20(L)×1(T)mm] electric field-vibration radiation transducer.

[0129] Figure 9 shows the intensity of the induced electric field when a voltage is applied to an electric field-vibration radiation transducer using a [Pb 0.965 Sr 0.02 Sm 0.01 [(Mg 1 / 3 Nb 2 / 3 ) 0.25 (Ni 1 / 3 Nb 2 / 3 ) 0.10 Zr 0.30 Ti 0.35 O3 piezoelectric single crystal, and Figure 10 shows the magnitude of the mechanical vibration when a voltage is applied.

[0130] As a result of measuring the intensity (magnitude) of the radiated electric field and the displacement of the mechanical vibration for the manufactured electric field-vibration radiation transducer, it was confirmed that an electric field and displacement (vibration) at an actually applicable level were induced.

[0131] <Example 4> Manufacture of an electric field-vibration radiation transducer using a piezoelectric single crystal-epoxy composite4 The [Pb0.965 Sr 0.02 Sm 0.01 ][(Mg 1 / 3 Nb 2 / 3 ) 0.25 (Ni 1 / 3 Nb 2 / 3 ) 0.10 Zr 0.30 Ti 0.35 The piezoelectric single crystal with the composition of ]O3 has a piezoelectric constant (d 33 The plate-shaped piezoelectric single crystal had a dielectric constant of 4,457 [pC / N], a dielectric constant of 14,678, and a dielectric loss (tan δ) of 1.0%, and the plate-shaped piezoelectric single crystal was cut using a dicing process, and epoxy (Epotek 301, Epoxy Technology Inc., USA) was poured into the cut parts in a 1:1 volume ratio and hardened to produce a 1-3 type composite.

[0132] Gold (Au) electrodes were formed on both sides [(001) surface] of the composite by a sputtering process, and the composite was then poled. After that, the Au electrode on one side was removed and cut to produce a plate-shaped [20 (L) x 20 (L) x 1 (T) mm] composite electric field-vibration radiation transducer.

[0133] For the electric field-vibration radiating transducer of the composite body thus manufactured, the intensity (magnitude) of the radiated electric field and the displacement of the mechanical vibration were measured. The results are shown in Table 2.

[0134] [Table 2]

[0135] The electric field strength (magnitude) and mechanical vibration displacement of the electric field emitted by the electric field-vibration radiating transducer using the piezoelectric single crystal-epoxy composite thus manufactured were measured, and it was found that the dielectric constant decreased in proportion to the epoxy content in the composite, but the displacement (vibration) increased by about 50%, compared to the piezoelectric single crystal alone (100%) in Example 3. Therefore, it was confirmed that the electric field-vibration radiating transducer of the composite has flexibility, improved fracture resistance, and improved displacement (vibration) characteristics.

[0136] Therefore, the electric field-vibration radiation transducer using the piezoelectric single crystal satisfying the dielectric and piezoelectric properties of the present invention as a dielectric material can be applied to medical devices for promoting material transfer, chemical action, and biological reaction, and for treating tumors in humans and animals.

[0137] Although the present invention has been described in detail above only with reference to the specific examples, it will be apparent to those skilled in the art that various modifications and variations are possible within the scope of the technical idea of ​​the present invention, and it goes without saying that such modifications and variations are within the scope of the appended claims. [Explanation of symbols]

[0138] 10 Electric Field-Vibration Radiation Transducer 11 Piezoelectric materials 12 electrodes 20 Voltage supply device 21 Electrical connection wire 30 Body parts such as head and skin 40 organization 41 Tumor 42 Electric Field 110 Polymer-Piezoelectric Composites 111 Polymer 112 Piezoelectric Composites

Claims

1. Perovskite crystal structure ([A][B]O ３ A piezoelectric material including a piezoelectric single crystal of an electrode formed on at least one surface of the piezoelectric material; Including, The piezoelectric constant (d ３３ ) is 1,000 to 6,000 pC / N, The dielectric constant of the piezoelectric material (K ３ Ｔ ) is between 6,000 and 15,000, and The dielectric loss of the piezoelectric material is 2% or less, so that the electric field and the mechanical vibration are simultaneously emitted, The piezoelectric single crystal is represented by the following chemical formula 1: Chemical formula 1 [A １－（ａ＋１．５ｂ） B ａ C ｂ ][(MN) １－ｘ－ｙ (L) ｙ Ti ｘ ]O ３－ｚ (In the above formula, A is at least one selected from the group consisting of Pb, Sr, Ba and Bi; B is at least one selected from the group consisting of Ba, Ca, Co, Fe, Ni, Sn, and Sr; C is at least one selected from the group consisting of Co, Fe, Bi, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu; L is selected from Zr or Hf, either alone or in mixture; M is at least one selected from the group consisting of Ce, Co, Fe, In, Mg, Mn, Ni, Sc, Yb, and Zn; N is at least one selected from the group consisting of Nb, Sb, Ta and W; 0.01≦a≦0.10, 0.01≦b≦0.05, 0.05≦x≦0.58, 0.05≦y≦0.62, and 0≦z≦0.

02. having a composition of 1. An electric field-to-vibration radiating transducer comprising:

2. The electrodes are formed on only one surface of the piezoelectric material, or when the electrodes are formed on both surfaces, they are asymmetrically formed by removing part or all of one of the electrodes.

2. The electric field-to-vibration radiation transducer of claim 1.

3. The piezoelectric material has a perovskite crystal structure ([A][B]O ３ ) is a polymer-piezoelectric composite containing a piezoelectric single crystal of 2. The electric field-to-vibration radiation transducer of claim 1.

4. In the above formula, a / b≧2.

2. The electric field-to-vibration radiation transducer of claim 1.

5. In the above formula, 0.10≦x≦0.58 and 0.10≦y≦0.

62.

2. The electric field-to-vibration radiation transducer of claim 1.

6. When L is a mixed form, the piezoelectric single crystal is represented by Formula 2 or Formula 3: chemical formula 2 [A １－（ａ＋１．５ｂ） B ａ C ｂ ][(MN) １－ｘ－ｙ (Zr) １－ｗ、 Hf ｗ ) ｙ Ti ｘ ]O ３ chemical formula 3 [A １－（ａ＋１．５ｂ） B ａ C ｂ ][(MN) １－ｘ－ｙ (Zr) １－ｗ、 Hf ｗ ) ｙ Ti ｘ ]O ３－ｚ (In the above formula, A, B, C, M, N, a, b, x, y, and z are the same as those in Chemical Formula 1, with the proviso that 0.01≦w≦0.20.) having a composition of The electric field-vibration radiation transducer of claim 1,

7. The composition of the piezoelectric single crystal further includes a reinforcing second phase (P) in an amount of 0.1 to 20% by volume to add mechanical properties; The strengthening second phase (P) is Au, Ag, Ir, Pt, Pd, Rh, MgO, ZrO ２ and pores.

2. The electric field-to-vibration radiation transducer of claim 1.

8. The polymer-piezoelectric composite comprises 10 to 80 volume percent of a polymer matrix.

4. The electric field-to-vibration emitting transducer of claim 3.

9. The polymer-piezoelectric composite has a 1-3 type or 2-2 type composite structure in which a rod-shaped piezoelectric material is embedded in a polymer matrix.

9. The electric field-to-vibration emitting transducer of claim 8.

10. The polymer-piezoelectric composite is formed by mixing a piezoelectric single crystal with a piezoelectric polycrystalline ceramic.

9. The electric field-to-vibration emitting transducer of claim 8.

11. The frequency of the emitted electric field is 0.01 Hz to 500 kHz, and the intensity of the electric field is 0.01 to 100 V / cm.

2. The electric field-to-vibration radiation transducer of claim 1.

12. The frequency of the emitted mechanical vibration is 0.1 Hz to 3 MHz, and the magnitude of the mechanical vibration is 1% or less.

2. The electric field-to-vibration radiation transducer of claim 1.

13. The electrode is any one selected from the group consisting of conductive metals, carbon, and conductive ceramics.

2. The electric field-to-vibration radiation transducer of claim 1.

14. The piezoelectric material has surface irregularities formed by pores or grooves (grooves, channels, etc.) on the surface.

2. The electric field-to-vibration radiation transducer of claim 1.

15. The perovskite crystal structure ([A][B]O) according to claim 1 ３ ) piezoelectric material is processed to a thickness of 0.1 to 100 mm, forming external electrodes on both sides of the piezoelectric material; applying a voltage to the external electrodes for poling; Either one of the external electrodes formed on both sides is partially or entirely removed to form an asymmetric structure.

23. A method for producing an electric field-vibration radiation transducer comprising:

16. The piezoelectric material has a perovskite crystal structure ([A][B]O ３ or a polymer-piezoelectric composite containing the piezoelectric single crystal. A method for manufacturing an electric field-to-vibration radiation transducer according to claim 15.

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