KR100707949B1 - Film speaker using 0-3 type piezoelectric composite and method of producing the same - Google Patents

Abstract

The present invention relates to a method for manufacturing a film speaker using a 0-3 type piezoelectric composite, and to form a lower electrode using a conductor such as ITO, Cu, Al, or a conductive polymer in order to impart conductivity to a base film. The piezoelectric composite layer vibrates in accordance with an electrical signal by a printing method or a doctor blade method, using a three-type composite (piezoelectric powder + polymer matrix) as a raw material, and the top of Ag, Carbon, Cu, Al, etc. The present invention relates to a film-type speaker, wherein the electrode is formed by a printing or vapor deposition method and polarized to be used as a thin speaker.

Film Speaker, Piezo, Composite, Printing, Deposition

Description

Film speaker using O-3 type piezoelectric composite and its manufacturing method {Film speaker using 0-3 type piezoelectric composite and method of producing the same}

1 is a cross-sectional view of a piezoelectric composite speaker according to an embodiment of the present invention.

Figure 2. Cross-sectional view of the piezoelectric composite according to an embodiment of the present invention

3. Exemplary circuit diagram of a film speaker

Figure 4 is a manufacturing process of the piezoelectric composite speaker according to an embodiment of the present invention

Explanation of symbols on the main parts of the drawings

1: base film 2: lower electrode

3: piezoelectric composite 4: upper electrode

31: Piezoelectric Powder 32: PVDF Medium

100: piezoelectric composite speaker 110: transformer

120: audio amplifier 130: audio signal input unit

140: terminal

The present invention relates to a method for manufacturing a film speaker using a 0-3 type piezoelectric composite, and to form a lower electrode using a conductor such as ITO, Cu, Al, or a conductive polymer in order to impart conductivity to a base film. -3 type composite (PZT powder + polymer matrix) is formed by piezoelectric composite layer vibrating according to electric signal by printing method or doctor blade method, and upper electrode such as Ag, Carbon, Cu, Al The present invention relates to a film-type speaker, which is formed by a printing or vapor deposition method and polarized to be used as a thin speaker, and a film-type speaker that facilitates mass production by forming electrodes by a method such as silk screen printing or deposition. It relates to a manufacturing method.

Type 0-3 refers to a state in which powder is evenly distributed in the polymer medium. Powders are not connected in any X, Y, or Z axis from the powder point of view (0). It is a structure (3) connected in all three directions.

Conventional coil diaphragm type speakers require a considerable amount of space and convert electrical power into acoustic power, but are very inefficient. Due to the mobility of the coil, there is a big limitation in space reduction.

On the other hand, when manufacturing a speaker with a conventional piezoceramic, it was difficult to manufacture a thin piezoelectric element having a thickness of 0.1 mm or less, and the piezoelectric element was very likely to be broken due to electrode formation. In addition, thin piezoelectric ceramics should be adhered to metal plates such as copper plates to be used.If the adhesive does not spread evenly or bubbles are generated during the bonding process, it may cause defects such as sound distortion. There was a limit.

The method for manufacturing a piezoceramic-polymer composite speaker disclosed in Patent Publication No. 1993-0008731, which is one of the prior arts, includes PbTiO3-PbZrO3-Pb (Zn1 / 3Nb2 / 3) O3 substituted with 0.1 to 0.9 mol% of Pb by Sr. The ceramic powder of MMA (Methylmethacrylate) is mixed in a volume ratio of 60:40, and a curing accelerator is put into a mold and cured by pressurizing.

The above invention has the inconvenience of having to pressurize during manufacture to cure the polymer as a basic method of the production of 0-3 type composite, and must be manufactured separately as the product range is diversified. In addition, since MMA having no piezoelectricity and a low dielectric constant is used, it is difficult to expect improvement in characteristics.

Meanwhile, in order to compensate for this, a technology of using a film speaker using a polyvinylidene difluoride (hereinafter referred to as 'PVDF'), which is a piezoelectric polymer, has been developed. PVDF has relatively good piezoelectric properties (d33 ≒ 25 ~ 30pC / N) (d33 is a piezoelectric constant indicating how much displacement is applied when a voltage is applied) and pyroelectric properties (i.e., electric charge It is known to have characteristics that generate voltage and generate voltage) and flexibility (that is, the piezoelectric ceramic is not easily broken and bent, but can be bent because it is a polymer film), and a piezoelectric polymer film having a polymer sheet shape is usually disposed between electrode layers. The length (l) and width (w) of the polymer film are considerably larger than the thickness (t), and the thickness (t) of the piezoelectric polymer film is mainly about 20 to 200 mu m.

In order to obtain the piezoelectric characteristics, DC high voltage must be applied to the upper and lower electrodes to align the internal electric dipoles in one direction. The process of applying such high voltage is called polarization. A speaker can be manufactured using PVDF, a polymer piezoelectric material. In the case of polarization work, a high electric field of 1MV / cm or more is required, and when polarizing at low voltage, the piezoelectric properties (d33 constant value is about 30pC / N has a value of 1/10 ~ 1/20 of piezoceramic) In addition, the upper and lower electrodes use a conductive polymer or Al deposition method, but since the surface of the PVDF is not hydrophilic, it is necessary to improve adhesion by using various surface modification methods (plasma treatment, ion beam treatment, etc.) due to the problem of adhesion. An additional process is needed. If the adhesion of the electrode on the surface is off for a long time, there is a problem that the electrode falls due to vibration.

In the case of film speaker using PVDF, PVDF film price is high and d33 value is low to use as a speaker, so high voltage (approximately 100Vrms or more) must be applied, and separate high voltage (approximately 100V or more) boosting amplifier to apply high voltage And a large impedance of the film, the transformer must be used for impedance matching, and there is a disadvantage in that the acoustic characteristics are poor in the bass region.

The present invention is to improve the shortcomings and problems of the prior art as described above, by using a piezoceramic-polymer composite, easy to manufacture, low-cost, ultra-thin and flexible piezoelectric film excellent speaker and its manufacture It is to provide a method.

The present invention is to provide a film-type speaker and a method for manufacturing the same, which is excellent in mass productivity using a printing and doctor blade method, and which is easy to mass produce and manufacture by forming an electrode by a method such as silk screen or deposition. .

In addition, the present invention is easy to control the characteristics and size through the adjustment of the printing thickness, the electrode control, the selection of the base film, the film that can easily mass-produce thin, lightweight products with a variety of design of the desired specifications It is to provide a type speaker and a method of manufacturing the same.

In addition, the present invention can easily print a variety of patterns and advertisements, such as by printing a pattern on the base film surface of the film-type speaker, and provides a film-type speaker and a method of manufacturing the same can also use a variety of base film design as it is It is to.

In addition, since the present invention can be driven at a lower voltage than conventional PVDF piezoelectric film, it is possible to prevent the loss due to excessive voltage boost, low impedance, easy to match, and also to reduce the power consumption film-type speaker and its manufacture To provide a way.

In another aspect, the present invention is to provide a film-type speaker and a method of manufacturing the same that can be easily controlled by adjusting the ratio of piezoelectric powder: PVDF medium.

In another aspect, the present invention is to provide a film-type speaker and a method of manufacturing the same that can be produced in a multi-layer structure to improve the acoustic characteristics.

In addition, the present invention is to provide a film-type speaker and a method for manufacturing the same, which can hear the sound regardless of a specific position because the mid-high treble is superior to the existing speaker and the sound spreading is wide.

In addition, since the present invention can be easily bent, the high, low and diffuseness of the sound can be adjusted according to the degree of bending, and when the curved surface is formed, the sound pressure can be concentrated to have a higher volume, and the front and rear surfaces of the film speaker To provide a film-like speaker and a method of manufacturing the same that can emit sound.

In order to achieve the above object, the piezoelectric composite speaker according to the present invention forms a lower electrode 2 on the base film 1, and has a piezoelectric composite 3 having a predetermined shape designed according to acoustic characteristics such as circular, square, and band shapes. It is characterized in that the base electrode (1) formed with the lower electrode (2) is formed by printing or a doctor blade method, and the upper electrode (4) is formed thereon. The upper electrode 4 and the lower electrode 2 are provided with terminals (not shown) for applying an external sound source signal.

More specifically, the piezoelectric composite speaker 100 of the present invention is a piezoelectric composite by mixing the piezoelectric powder 31 having a high piezoelectric constant and the PVDF medium 32, which is a piezoelectric polymer, in an appropriate ratio (5: 5 to 7: 3). (3), and the piezoelectric composite 3 is formed on the base film 1 provided with the lower electrode 2 by printing or a doctor blade method, and the upper electrode 4 is also made of a conductive polymer, carbon (carbon), silver, or formed by printing a metal, such as Cu, Al, Ag, and the like, characterized in that it gives a piezoelectricity through polarization, and the amplified external sound source signal to the electrodes (2, 4) The terminal 140 is applied to the piezoelectric composite speaker 100 that emits sound by causing mechanical vibration of the piezoelectric composite 3.

The Doctor Blade method is a general process for making green sheets, and has a height-adjustable blade that is spaced apart from the bottom plate.The desired material is made into a slurry and a film is placed on the bottom plate. When poured, the slurry comes out through the gap between the blade and the lower plate and is coated on the film. When the film is pulled at a constant speed, the slurry is continuously formed in a constant thickness.

In the electrode forming method, the silk screen forms a pattern of a desired shape on the silk net and passes the ink between the silk nets to print on the film. Although the printing method is typically used in the present invention, other printing methods are also used in the present invention. Of course, it can be applied to.

As the deposition method in the electrode formation method, a conventional deposition method using CVD, PVD, sputtering, E-Beam, or the like is used.

Hereinafter, the present invention will be described in detail through embodiments of the present invention shown in the accompanying drawings.

1 is a cross-sectional view of a piezoelectric composite speaker 100 according to a first embodiment of the present invention.

In the piezoelectric composite speaker 100 according to the present invention, the lower electrode 2 is formed on the base film 1, and the piezoelectric composite 3 having a predetermined shape is formed on the base film 1 on which the lower electrode 2 is formed. And the upper electrode 4 formed thereon. The upper electrode 4 and the lower electrode 2 are provided with terminals (not shown) for applying an external signal.

As the base film 1, polymer films such as polyethylene naphthalate (PEN), polyethylene terephtalate (PET), and polystyrene (PS) are used. The base film 1 may be provided with decorations such as patterns and patterns having various colors by a method such as pattern printing.

The lower electrode 2 is formed on the base film 1 by printing an Ag paste, a carbon paste, a conductive polymer, or depositing a conductive material such as Cu, Al, Ag, or ITO.

The condition that the lower electrode 2 layer should be provided is thermally stable than the piezoelectric composite 3 film to be placed thereon, exhibits low sheet resistance, and mechanically has a low Young's modulus.

Ag paste and carbon paste have proper viscosity for printing, and Ag or Carbon particles (particle size of about 10㎛) are mixed with solvent and binder, and drying temperature is less than 150 degrees. Low temperature electrode material.

Conductive polymers include conductive polymers such as polyaniline, polythiophene, PEDOT (poly (3,4-ethylene-dioxythiophene)), polypyrrole, PPV (polyphenylenevinylene), derivatives thereof, and organic conductors.

On the lower electrode 2, a piezoelectric composite 3 layer is formed using a 0-3 type piezoelectric composite. 2 illustrates a cross-sectional structure of the piezoelectric composite 3 of the present invention. The piezoelectric composite 3 of the present invention is composed of a mixture of a piezoelectric powder 31 and a PVDF medium 32.

In the case of the piezoelectric composite 3, the dielectric constant is large and the loss tangent to frequency is stably small, and the leakage current should be minimized. To this end, it is necessary to reduce the thickness or increase the area of the piezoelectric composite 3 and use the piezoelectric powder 31 having a high dielectric constant. PZT having the following composition illustrated in the present invention is a composition having a relative dielectric constant of about 6,000. On the other hand, PZT has a piezoelectric constant of up to 100 ~ 750pC / N depending on the composition.

The piezoelectric powder 31 may be used as long as it is a piezoelectric powder having a high piezoelectric constant such as PZT (Pb (Ti, Zr) O3) or lead-free such as BNT or SBT. In the embodiment of the present invention, the piezoelectric powder 31 has PbO to have a composition of (Pb1-a-bBaaCdb) (Ni 1/3 Nb 2/3) c (Zn 1/3 Nb 2/3) d (ZrxTi1-x) 1-c-dO 3. , BaCO3, CdO, NiO, Nb2O5, ZnO, ZrO2, TiO2 powder was synthesized, the relative dielectric constant is about 6,000, d33 piezoelectric constant is 700pC / N.

 The piezoelectric powder 31 should be evenly distributed on the PVDF medium 32, and the piezoelectric powder 31 may have a size of about 2 µm or less, and sintered powder is pulverized by a conventional ball mill method. . In order to obtain a finer particle size, a high energy ball mill or the like can be used.

The PVDF medium 32 is a polymer mixture in which an additive such as HFP, CTFE, or PTFE is added to the PVDF, and may be prepared by using VDF (Vinylidenefluoride) or TrFE (TrFE) instead of PVDF, and adding the above additive.

On the piezoelectric composite 3, the upper electrode 4 is formed by using a conductive paste such as a conductive polymer, Ag paste, carbon paste, or the like by silkscreen printing or spraying, or a conductive material such as Cu, Al, ITO, or the like. The upper electrode 4 is formed by vapor deposition (sputtering, vacuum deposition, etc.). Conductive polymers usable as the upper electrode 4 include conductive polymers such as polyaniline, polythiophene, poly (3,4-ethylenc dioxythiophene) (PEDOT), polypyrrole, polyphenylenevinylene (PPV), derivatives thereof, and organic conductors. In the case of the conductive polymer, since the resistance is high, it should be formed to an appropriate thickness (about 3㎛ or more). In case of printing with Ag paste or carbon paste, it is important to make the thickness as thin as possible because the resistance is low so that the negative pressure characteristic does not change with the weight of the electrode. In the case of the upper electrode 4, it is important to design and form a pattern on the silk screen so that there is no short phenomenon with the lower electrode that may occur during polarization.

3 is a manufacturing process chart of the piezoelectric composite speaker of the present invention.

The piezoelectric composite speaker 100 manufacturing method of the present invention can be broadly divided into the production of the piezoelectric composite 3, the formation of the base film 1 and the lower electrode 2, the upper electrode 4, and the post-treatment process. .

The base film 1 is provided with a polymer film such as polyethylene naphthalate (PEN), polyethylene terephtalate (PET), polystylene (PS), etc. having a thickness of 15 to 100 μm (step 300).

The base film 1 may be decorated with patterns and patterns having various colors, such as by printing patterns. The piezoelectric composite speaker 100 can be effectively used in various patterns and shapes according to the intended use and atmosphere.

The lower electrode 2 is formed by printing Ag paste, carbon paste, conductive polymer on the base film 1 or depositing a conductive material such as Cu, Al, Ag, ITO, or the like (step 310).

ITO electrode is commercially available by depositing about 300 Å on PET, PET has a minimum thickness of about 50㎛. Ag, Carbon is about 10㎛, conductive polymer is about 3㎛ thick, and when depositing Cu, Al, Ag, etc., depending on the deposition time and conditions, about 2,000 ~ 10,000Å, ITO It is formed around 300Å.

The piezoelectric composite layer 3 is formed on the lower electrode 2 using a 0-3 type piezoelectric composite, and the thickness is formed to be approximately 30 μm or more, but may vary slightly depending on the mixing ratio.

A piezoelectric powder 31 is produced as a component of the piezoelectric composite 3. For the illustrated composition, BaCO 3, CdO, NiO, Nb 2 O 5, ZnO, ZrO 2, TiO 2 powders are weighed (step 320), mixed using a ball mill and calcined at 800-900 ° C. for 4 hours (step 322). The calcined powder was pulverized using a ball mill, sintered at 1000 to 1100 ° C. for 2 to 4 hours to form a sintered powder, and then pulverized for 48 hours to produce a piezoelectric powder 31 having a particle size of 2 μm or less. (Step 324).

Next, the piezoelectric powder 31 and the PVDF medium 32 are mixed in a weight ratio of 50 to 70 wt%: 30 to 50 wt%, preferably 65 wt%: 3 wt% to prepare a slurry.

PVDF powder is melted by heating in a solvent (NMP, DMF, DMAc, Acetone, etc.) to prepare a liquid PVDF medium (32), 50 ~ 70wt% mixture of piezoelectric powder (31) and PVDF medium (32) by weight ratio (Step 330). At this time, additives such as a dispersant and an antifoaming agent are added to meet the conditions, and the mixture is sufficiently stirred using a ball mill or a three-roll mill or an impeller to produce a slurry having a viscosity of about 7,000 ps, which can be printed thereon, and then printing. And adjusting to implement the doctor blade method (step 332).

The lower the amount of PVDF medium 32 added, the better the piezoelectric characteristics (represented by the piezoelectric constant d33, which represents the displacement amount when voltage is applied), but there is no bubble between the piezoelectric powder 31 and the PVDF medium 32 and the piezoelectric In order for the composite 3 to be uniformly produced, an appropriate ratio is required. In the examples of the present invention, a ratio of 65:35 was found to be appropriate.

Subsequently, the base film 1 provided with the lower electrode 2 is placed on a printing machine, and the printing and drying processes are repeated several times to obtain a desired thickness using a silk screen in which a pattern is formed (step 340) or the doctor blade method or the like. In step 342, the piezoelectric composite 3 layer is formed to have an even thickness.

In the case of using the doctor blade method, the blade blades are formed at a constant velocity at a desired height. On the other hand, if the pattern is required to form a pattern on the silk screen, the silk screen mesh is formed by selecting a mesh of about 150 ~ 200. Moreover, as for temperature in a drying process, 120-150 degreeC is preferable.

On the piezoelectric composite 3, the upper electrode 4 is formed by using a conductive paste such as a conductive polymer, Ag, or carbon paste, by silk screen printing, spraying, or the like, or a conductive material such as Cu, Al, or ITO is formed. The upper electrode 4 is formed by vapor deposition (sputtering, vacuum deposition, etc.) (step 350).

Subsequently, an electric field of 4 KV / mm (about 1 MV / cm in the case of a conventional PVDF film) is applied to the piezoelectric composite 3 as a post-treatment process to polarize it to impart piezoelectricity (step 360). The method or corona polarization method can be selected, and the polarization is performed at a temperature of approximately 80 to 120 ° C., and the d33 value is preferably 20 to 100 pC / N.

As shown in FIG. 4, the basic configuration for driving the piezoelectric composite speaker 100 according to the exemplary embodiment of the present invention includes an audio signal input unit 130, an audio amplifier 120 including a circuit for amplifying the signal, and a piezoelectric element. The booster transformer 110 outputs a voltage to the composite speaker 100. This is the same as a film speaker using a conventional PVDF film. The output terminals of the boost transformer 110 are connected to the electrodes 140 of the piezoelectric composite speaker, respectively.

When voltage difference occurs at both ends of the upper and lower electrodes 4 and 2 on both sides of the piezoelectric composite speaker 100, displacement of the piezoelectric composite 3 occurs, and mechanical vibration is generated according to the frequency of the input sound source. The air is pushed out to generate sound.

Since the piezoelectric composite speaker 100 is flexible, the piezoelectric composite speaker 100 may be manufactured in various shapes and patterns. The piezoelectric composite speaker 100 may be formed in a curved surface to concentrate the sound pressure to have a larger volume. And it is possible to radiate sound to the front and rear of the piezoelectric composite speaker by making a curved surface using a light frame frame support such as a plastic material of excellent ductility.

As in the case of a film speaker using a conventional PVDF piezoelectric film, the principle of supplying a voltage to the piezoelectric composite speaker of the present invention is that an audio signal from a sound source such as an audio device is input to the audio signal input unit 130 and the audio amplifier 120 Amplified to a predetermined level, and the amplified audio signal passes through the boosting transformer 110, and the voltage is amplified, and the amplified signal is passed through the terminal 140 of the piezoelectric composite speaker 100. 100 is applied to the piezoelectric composite 3 to vibrate according to the voltage signal, and the sound comes from the piezoelectric composite speaker 100.

 Like the PVDF piezoelectric film, the piezoelectric composite has a higher impedance than the conventional speaker, and thus the impedance must be matched using the transformer 110 and the audio amplifier 120.

5 is a manufacturing process diagram of the piezoelectric composite speaker according to the second embodiment of the present invention.

In the piezoelectric composite speaker according to the second embodiment, the lower electrode 2 is formed on the base film 1, and the piezoelectric composite 3 is formed on the base film 1 on which the lower electrode 2 is formed. The upper electrode 4 is formed thereon, the piezoelectric composite body 33 of the second layer is formed on the upper electrode 4 by printing or a doctor blade method, and the second upper electrode 41 is formed. By repeating the same process, the n-layer is laminated according to the required properties. The piezoelectric coefficient d33 increases linearly with the number of laminations.

In the case of the present invention, the piezoelectric composites 3 and 33 and the electrodes 2, 4 and 41 are formed by printing or the doctor blade method, so that the acoustic characteristics can be improved by a simple process. 2, 3, 4,... With electrodes between them. In the case of lamination with n layers, even when the same voltage is applied during lamination, the total displacement of the piezoelectric composite can be improved by the number of laminated layers, so that the sound pressure characteristics can be improved. This is the same principle as the laminated piezo actuator.

In the above, the present invention has been described through the first and second embodiments of the present invention, but the scope of the present invention is not limited to the described embodiments, and various modifications are made by those skilled in the art within the scope of the claims based on the appended claims. It is obvious that modifications or changes are possible.

Since the film speaker of the present invention uses the printing and doctor blade method, it is excellent in mass productivity and is easy to produce and manufacture in large quantities by forming electrodes by a method such as silk screen or vapor deposition. It can be produced at a price of about 1/10.

The film speaker of the present invention is easy to adjust the characteristics and the size through the adjustment of the printing thickness, the electrode control, the selection of the base film, and can easily mass-produce thin, lightweight products having various designs of the desired specifications. It can be effective.

Various patterns and advertisements can be easily printed by printing patterns on the base film surface of the film speaker of the present invention, and various base films can be used as they are.

Since the film speaker of the present invention can be driven at a lower voltage than the conventional PVDF piezoelectric film, it is possible to prevent loss due to excessive voltage boost, low impedance and easy matching, and power consumption can be reduced.

In addition, the film speaker of the present invention can be easily controlled by controlling the ratio of piezoelectric powder: PVDF medium.

In addition, the piezoelectric composite speaker of the present invention can linearly improve performance by laminating, thereby providing a product suitable for the purpose.

In addition, the film speaker of the present invention can hear the sound regardless of the specific position because the mid-high pitch range is superior to the existing speaker and the sound spreading is wide.

In addition, since the film speaker of the present invention can be easily bent, it is possible to adjust the high, low and diffusivity of the sound according to the degree of bending, and when it is formed into a curved surface, the sound pressure can be concentrated to have a larger volume, and the film speaker Sound can be radiated to the front and back of.

In addition, the piezoelectric composite of the present invention can be widely applied to various applications of piezoelectric sensors in addition to film-type speakers.

Claims (20)

A base film formed of a polymer film; A lower electrode layer formed on the base film; A piezoelectric composite layer disposed on the lower electrode layer and composed of a 0-3 type composite of a piezoelectric powder and a piezoelectric polymer matrix; And A piezoelectric composite film speaker comprising an upper electrode layer formed on the piezoelectric composite layer. A base film formed of a polymer film; A plurality of electrode layers formed by printing or vapor deposition; And It comprises a plurality of piezoelectric composite layer consisting of a 0-3 type composite of the piezoelectric powder and the piezoelectric polymer matrix, The electrode layer and each piezoelectric composite layer is repeatedly stacked in an alternating manner, and the base film is a piezoelectric composite film speaker, characterized in that disposed below the lowest electrode layer. The method according to claim 1 or 2, The polymer matrix is a PVDF medium, the piezoelectric composite film type speaker comprising an additive selected from the group consisting of HFP, PTFE, CTFE in the PVDF. The method according to claim 1 or 2, The polymer matrix is a PVDF medium, the piezoelectric composite film type speaker comprising a PVDF and PVDF derivative. The method according to claim 1 or 2, The electrode layer is a piezoelectric composite film speaker, characterized in that formed of a material selected from the group consisting of Ag, Al, Cu, ITO, carbon and a conductive polymer. The method according to claim 1 or 2, The polymer film is a piezoelectric composite film speaker, characterized in that selected from the group consisting of PEN, PET and PS. A base film formed of a polymer film selected from the group consisting of PEN, PET and PS; A first electrode layer formed on the base film and formed of a material selected from the group consisting of Ag, Al, Cu, ITO, carbon, and a conductive polymer; A piezoelectric composite layer disposed on the lower electrode and formed of a mixture in which a PVDF medium including a PVDF and a PVDF derivative and a piezoelectric powder are mixed in a ratio of 30 to 50 wt%: 50 to 70 wt%; And And a second electrode layer formed on the piezoelectric composite and formed of a material selected from the group consisting of Ag, Al, Cu, ITO, carbon, and a conductive polymer. The method of claim 7, wherein The piezoelectric composite layer and the second electrode layer is composed of a plurality of layers each of the same number, the piezoelectric composite film-type speaker, characterized in that laminated repeatedly in an alternating manner. Providing a base film formed of a polymer film; Forming a lower electrode on the base film; Forming a piezoelectric composite composed of a 0-3 type composite of a piezoelectric powder and a piezoelectric polymer matrix on the lower electrode; And Piezoelectric composite film-type speaker manufacturing method comprising the step of forming an upper electrode on the piezoelectric composite. Providing a base film formed of a polymer film; Forming an electrode layer on the base film; Forming a piezoelectric composite layer composed of a 0-3 type mixture of a piezoelectric powder and a piezoelectric polymer matrix on the electrode layer; And Piezoelectric composite film type speaker comprising the step of alternately repeating the electrode layer forming step and the piezoelectric composite layer forming step. The method according to claim 9 or 10, The piezoelectric complex forming step, Mixing the piezoelectric powder and the piezoelectric polymer matrix; Adding a dispersant and an antifoaming agent; A method of manufacturing a piezoelectric composite film speaker, comprising: preparing a piezoelectric composite in a paste form having a predetermined viscosity by stirring the mixture to which the dispersing agent and the antifoaming agent are added. The method of claim 11, The piezoelectric complex forming step, The piezoelectric composite film-type speaker manufacturing method further comprises the step of printing the piezoelectric composite in the form of a paste on the lower electrode. The method of claim 11, The piezoelectric complex forming step, The piezoelectric composite film-type speaker manufacturing method further comprises the step of forming the paste-shaped piezoelectric composite on the lower electrode by the doctor blade method. The method according to claim 9 or 10, The base film providing step further comprises the step of pattern-printing the pattern on the base film piezoelectric composite film type speaker manufacturing method. The method according to claim 9 or 10, The upper electrode forming step and the lower electrode forming step is a piezoelectric composite film type speaker manufacturing method, characterized in that for printing a material selected from the group consisting of Ag, carbon and a conductive polymer. The method according to claim 9 or 10, The forming of the upper electrode and the forming of the lower electrode is a piezoelectric composite film type speaker manufacturing method, characterized in that for depositing a material selected from the group consisting of Cu, Al, Ag and ITO. The method according to claim 9 or 10, Mixing of the piezoelectric powder and the polymer matrix, Dissolving the PVDF powder in a solvent while heating to prepare a liquid PVDF medium; And And mixing the piezoelectric powder and the PVDF medium at a ratio of 50 to 70 wt%: 30 to 50 wt%, The paste form manufacturing step is a piezoelectric composite film-type speaker manufacturing method characterized in that the step of treating the stirred mixture in the form of a method selected from the group consisting of a ball mill method, a three-roll mill method and an impeller method. The method of claim 9, The piezoelectric complex forming step, The piezoelectric composite film speaker manufacturing method characterized in that the printing step on the lower electrode. The method of claim 9, The piezoelectric complex forming step, Piezoelectric composite film manufacturing method characterized in that the step of forming the piezoelectric composite on the lower electrode by the doctor blade method. A piezoelectric composite film speaker produced by the method of claim 18 or 19.

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