KR102091701B1 - Module for recognizing biometric information of finger and electronic device using the same and manufacturing method of module for recognizing biometric information of finger and manufacturing method of transducer - Google Patents

Abstract

According to the present invention, when the characteristics of the transducer are changed, when recognizing biometric information of a finger using ultrasonic waves, a finger biometric information recognition module that increases a recognition rate of ultrasonic waves and improves precision for recognizing biometric information of a finger. , It relates to an electronic device to which this is applied, and a method of manufacturing a transducer for the same.
To this end, the finger biometric information recognition module outputs ultrasound toward the finger, and the transducer and the transducer receiving the ultrasonic wave reflected from the finger and returning the ultrasonic wave output the ultrasonic wave, and the ultrasonic wave transmitted and received to and from the transducer is transmitted to the transducer without loss. It includes a sound wave control member that is laminated and a signal processing unit that senses biometric information of a finger according to ultrasonic waves that are electrically connected and received.

Description

Finger biometric information recognition module, electronic device to which it is applied, and manufacturing method of finger biometric information recognition module and manufacturing method of a transducer OF FINGER AND MANUFACTURING METHOD OF TRANSDUCER}

The present invention relates to a finger biometric information recognition module, an electronic device to which it is applied, and a manufacturing method of a finger biometric information recognition module and a manufacturing method of a transducer, and more specifically, by changing characteristics of the transducer, using ultrasound When recognizing biometric information of a finger, a finger biometric information recognition module that increases a recognition rate of ultrasonic waves and improves precision for recognizing a biometric information of a finger, an electronic device to which it is applied, and a method of manufacturing a finger biometric information recognition module And a method of manufacturing the transducer.

In general, a fingerprint recognition sensor is a sensor that detects a human fingerprint, and is used to determine an on / off or a sleep mode of an electronic device power supply, as well as a device such as a door lock, which has been widely applied in the past.

The fingerprint recognition sensor may be classified into an ultrasonic method using ultrasonic waves, an optical method using infrared rays or ultraviolet rays, and a capacitive method using capacitance according to the operating principle of the core device. Among these, the ultrasonic method returns a different frequency because ultrasonic waves of a certain frequency emitted from a plurality of piezoelectric sensors return differently due to a difference in acoustic impedance in the valley (VALLEY) and the floor (RIDGE) of the fingerprint. Fingerprint can be recognized by measuring using a piezoelectric sensor.

Recently, a finger biometric information recognition module has been developed to detect blood vessels (finger veins, etc.) distributed over a finger of a person beyond detection of a fingerprint. Such finger biometric information recognition technology is impossible to falsify or tamper, and is rapidly emerging as a personal authentication means due to its high accuracy.

However, as the importance of the security of the electronic device increases, the finger biometric information recognition module needs to increase the recognition rate of the biometric information through the module. In particular, since the finger vein is located inside the finger compared to the fingerprint, ultrasound must be stably transmitted to the inside of the finger, and the returning ultrasound must be stably received. Here, when the sensitivity of the piezoelectric sensor is increased to increase the recognition rate of the finger vein, additional problems such as increasing the power consumption of the miniaturized electronic device, increasing the cost of the piezoelectric sensor, and shortening the life of the piezoelectric sensor, are implied. have.

Republic of Korea Patent Publication No. 2015-0080812 (name of invention: fingerprint sensor and electronic device including the same, published on July 10, 2015)

An object of the present invention is to solve the conventional problems, and by changing the characteristics of the transducer, when recognizing the biometric information of the finger using ultrasonic waves, the recognition rate of the ultrasonic wave is increased, and the precision for recognizing the biometric information of the finger is improved. The present invention provides a finger biometric information recognition module that can be improved, an electronic device to which it is applied, and a method of manufacturing a finger biometric information recognition module and a transducer.

According to a preferred embodiment for achieving the object of the present invention described above, the finger biometric information recognition module according to the present invention is a finger biometric information for recognizing biometric information including at least one of a finger vein and a fingerprint from a contacted finger It is a recognition module, a transducer for outputting ultrasonic waves toward the finger, and receiving ultrasonic waves reflected back from the finger; A sound wave control member stacked on the transducer so that ultrasonic waves transmitted and received are transmitted without loss; And a signal processing unit configured to cause the transducer to output ultrasonic waves and to detect biometric information of the finger according to ultrasonic waves that are electrically connected to the transducer and received, and wherein the transducer is vertically and horizontally in a two-dimensional plane. A plurality of unit piezoelectric cells spaced apart from each other; And a filling material filled between the unit piezoelectric cells adjacent to each other. The unit piezoelectric cell includes at least one of an inorganic piezoelectric material and an organic piezoelectric material.

Here, the unit piezoelectric cell, the base material is processed by a dry etching technique or a micro-molding technique to exhibit a column shape.

Here, a plurality of pores are formed in the inorganic piezoelectric material in communication with each other, and the organic piezoelectric material surrounds the outer circumferential surface of the inorganic piezoelectric material or is formed in the pores.

The finger biometric information recognition module according to the present invention is a finger biometric information recognition module for recognizing biometric information including at least one of a finger vein and a fingerprint from a contacted finger, outputs ultrasound toward the finger, and from the finger A transducer that receives reflected and returning ultrasound; A sound wave control member stacked on the transducer so that ultrasonic waves transmitted and received are transmitted without loss; And a signal processing unit configured to cause the transducer to output ultrasonic waves and to be electrically connected to the transducer and detect bio-information of the finger according to the received ultrasonic waves. The transducer includes ultrasonic waves toward the finger It includes; a plate-shaped piezoelectric plate for outputting.

Here, the piezoelectric plate includes aluminum nitride (AlN) or lead zirconate titanate (PZT, PbZrTiO3).

The finger biometric information recognition module according to the present invention further includes an ultrasonic transmission member that is inserted and stacked between the transducer and the sound wave control member so that ultrasound is transmitted between the transducer and the sound wave control member.

The finger biometric information recognition module according to the present invention further includes a post member for forming a vacuum space between the transducer and the signal processing unit to prevent ultrasonic waves from being transmitted to the signal processing unit.

Here, the signal processing unit is connected to the transducer, the ultrasonic driving unit for applying a driving signal to the transducer so that the ultrasonic output from the transducer; An ultrasonic processing unit connected to the transducer and processing ultrasound received from the transducer; A multiplexing logic unit that selects and outputs a specific signal that satisfies a condition from among the signals of the ultrasonic processing unit; A signal converting unit converting a signal output from the multiplexing logic unit; And a signal processing control unit controlling the driving signal applied from the ultrasonic driving unit so that the frequency of ultrasonic waves is adjusted, and controlling the operation of the ultrasonic processing unit, the multiplexing logic unit, and the signal conversion unit in response to the controlled driving signal. Includes.

Here, the ultrasonic processing unit further includes monitoring the received ultrasonic signal and correcting the received ultrasonic signal by extracting a signal for a fingerprint or a finger vein from the received ultrasonic signal.

Here, when the signal processing control unit controls the driving signal so that the frequency of the ultrasonic wave output from the transducer indicates the first frequency, the signal processing unit detects the fingerprint and finger vein of the finger, and the transducer When the signal processing controller controls the driving signal so that the frequency of the output ultrasonic wave is greater than the first frequency, the signal processing unit detects the fingerprint of the finger.

Here, the signal processing unit, Hilbert conversion unit for generating a converted signal by Hilbert transform the signal converted by the signal conversion unit; A shaping unit for shaping a transform signal generated through the Hilbert transform unit to generate a shaping signal; An image replacement unit for generating a replacement signal by replacing the normalization signal generated through the shaping unit with a 3D image element; A logic synthesizing unit that generates a 3D signal by synthesizing substitution signals generated through a plurality of the image replacement units; And an image acquisition unit that acquires a final 3D image based on the 3D signal generated through the logical synthesis unit.

The electronic device according to the present invention includes the above-described finger biometric information recognition module; And a main control unit controlling an electronic device based on a signal output from the signal processing unit.

The method of manufacturing a transducer according to the present invention is a method of manufacturing the above-described transducer using a dry etching technique, and a thick film manufacturing method of manufacturing a composite piezoelectric thick film using at least one of an inorganic inorganic piezoelectric material and the organic piezoelectric material step; A thick film cutting step of cutting the composite piezoelectric film produced through the thick film manufacturing step so that a partition slit is formed in the composite piezoelectric film; And a slit filling step of filling the compartment slit with the filling material.

Here, the thick film manufacturing step, the stacking step of stacking a template for forming pores in the base; A precursor solution impregnating step of impregnating the temple with a precursor solution of the inorganic piezoelectric material after the temple stacking step; A drying step of passing the precursor solution impregnation step and then drying the precursor solution of the inorganic piezoelectric material; After the drying step, a template removal step of removing the template from the dried precursor of the inorganic piezoelectric material; A crystallization step of crystallizing a precursor solution of the dried inorganic piezoelectric material after passing through the temple removal step; An organic material input step of introducing the organic piezoelectric material into the precursor solution of the inorganic piezoelectric material crystallized after the crystallization step; And a thickening step of mixing the crystallized precursor solution of the inorganic piezoelectric material and the organic piezoelectric material to form the composite piezoelectric film.

The manufacturing method of the transducer according to the present invention is a method of manufacturing the above-described transducer using a micro-molding technique, and the inorganic piezoelectric material or the organic piezoelectric material or a mixed material obtained by mixing the inorganic piezoelectric material and the organic piezoelectric material Preparing a; Preparing a molding mold in which a cell groove corresponding to the unit piezoelectric cell is formed; Injecting the organic piezoelectric material or the inorganic piezoelectric material or the mixed material into the molding mold to produce a green array in which the unit piezoelectric cell is formed on a base layer; Sintering the green array to produce a sintered array; Separating the green array or the sintered array from the molding mold; And filling a filling material between the unit piezoelectric cells adjacent to each other in the sintered array.

A method of manufacturing a transducer according to the present invention includes removing a base layer from the sintered array filled with the filler so that only the unit piezoelectric cell and the filler remain in the sintered array; And forming electrodes on both ends of the unit piezoelectric cell.

The method of manufacturing a finger biometric information recognition module according to the present invention is a method of manufacturing the above-described finger biometric information recognition module by applying the plate-shaped piezoelectric plate, and preparing a support for stacking the upper electrodes; Sequentially stacking the upper electrode, the piezoelectric plate, and the lower electrode on the sound wave control member; Etching the lower electrode to separate the lower electrode in the form of a plate corresponding to the unit cell; Forming a via hole in the piezoelectric plate, and patterning connection lines for applying power to the upper electrode and the separated lower electrode to form the transducer; Laminating the transducer and the support to the signal processing unit so that the signal processing unit and the connection line are electrically connected; And stacking the sound wave control member on the support portion.

The method for manufacturing a finger biometric information recognition module according to the present invention is performed before the transducer is stacked on the signal processing unit, and a post member for preventing ultrasonic waves from being transmitted to the signal processing unit is stacked on the signal processing unit. Step; further comprises.

The method of manufacturing a finger biometric information recognition module according to the present invention is a method of manufacturing the above-mentioned finger biometric information recognition module by applying the plate-shaped piezoelectric plate, and ultrasonic transmission forming a transmission path of ultrasonic waves transmitted and received by the transducer. Preparing a transfer base material for forming a member; Sequentially stacking the upper electrode, the piezoelectric plate, and the lower electrode on the transfer base material; Etching the lower electrode to separate the lower electrode in the form of a plate corresponding to the unit cell; Forming a via hole in the piezoelectric plate, and patterning connection lines for applying power to the upper electrode and the separated lower electrode to form the transducer; Stacking the transducer and the transmission base material on the signal processing unit so that the signal processing unit and the connection line are electrically connected; And processing the transmission base material to form the ultrasonic transmission member.

The method for manufacturing a finger biometric information recognition module according to the present invention further comprises laminating the sound wave control member on the ultrasonic transmission member.

According to the finger biometric information recognition module according to the present invention, an electronic device to which it is applied, and a method of manufacturing a finger biometric information recognition module and a method of manufacturing a transducer, the characteristics of the transducer are changed, and thus the biometric information of the finger using ultrasonic waves When recognizing, it is possible to increase the recognition rate of the ultrasound and improve the precision for recognizing biometric information of the finger.

In addition, the present invention stably matches the acoustic impedance between the transducer and the finger by changing the characteristics of the transducer, and it is possible to omit a separate matching member.

In addition, the present invention can reduce the vibration component (coupling) between adjacent unit piezoelectric cells, as well as reducing the horizontal component (lateral mode) perpendicular to the direction of travel of the vibration components generated in the unit piezoelectric cell, unit The piezoelectric cell can be individually driven and individually received, and the transmission characteristics of ultrasonic waves and the reception characteristics of ultrasonic waves can be improved in a unit piezoelectric cell.

In addition, according to the present invention, the driving signal of the ultrasonic wave and the reception signal of the ultrasonic wave are separated from the unit piezoelectric cell, and thus the transmission characteristics of the ultrasonic wave and the reception characteristics of the ultrasonic wave can be improved in the unit piezoelectric cell.

In addition, the present invention simplifies the manufacture of the transducer by simplifying the combination of the inorganic piezoelectric material and the organic piezoelectric material in the unit piezoelectric cell, as well as preventing the loss of ultrasonic power or ultrasonic energy in the unit piezoelectric cell, and the skin of ultrasound. The penetration rate can be improved.

In addition, according to the present invention, both the ultrasonic wave transmitted through the transducer and the sound wave control member and the received ultrasonic wave are transmitted without energy loss, thereby improving the transmission / reception sensitivity of the ultrasonic wave, the transmittance of the ultrasonic wave, the reflectance of the reflected wave, and the transmission power of the evanescent wave. To improve, it is possible to stably match the acoustic impedance between the transducer and the finger, and a separate matching member can be omitted.

In addition, the present invention can stably receive the extinction wave having a small wavelength and amplitude from the transducer through the sound wave control member and stably transmit it to the signal processing unit.

In addition, the present invention stably induces the ultrasonic wave input from the sound wave control member in the traveling direction, induces resonance of the ultrasonic wave from the sound wave control member, and allows the input ultrasonic wave to be transmitted without loss of energy between the contact member and the signal processing unit. Can stabilize the transmission of ultrasound.

In addition, the present invention can prevent attenuation of ultrasonic waves, stabilize the transmission of ultrasonic waves, and stably match the acoustic impedance with fingers by filling the control matching member in a portion formed through the sound wave control member.

In addition, the present invention can be used in combination with the recognition of the finger vein and fingerprint recognition by adjusting the frequency of the ultrasound, by accurately capturing the flow of finger finger vein, fingerprint, etc. Dimensional images can be implemented.

In addition, the present invention can improve security according to the recognition of a fingerprint or finger vein in an electronic device and protect personal information embedded in the electronic device.

In addition, the present invention realizes micro-processing in the micrometer unit for controlling the sound in the ultrasonic region, facilitates the manufacture of the sound wave control member, improves strength of the structure of the sound wave control member, and supports the structure. Or it can increase the holding force.

In addition, the present invention can simplify the centering between the first signal transmission groove and the second signal transmission groove and the connection line formed in the sound wave control member, and minimize stacking errors to prevent defects in the sound wave control member.

In addition, the present invention can reduce the height of the sound wave control member and contribute to miniaturization and thinning of the finger biometric information recognition module.

In addition, the present invention enables imaging of finger vein or fingerprint even if there is a contaminant (dust, sweat, residual cosmetics, etc.) on the finger, and correlates to the material (glass, aluminum, sapphire, plastic, etc.) of the contact member that the finger contacts. Without a signal processing unit, finger vein or fingerprint recognition is possible, and the design of a finger biometric information recognition module can be facilitated in an electronic device.

In addition, the present invention can obtain a high-resolution three-dimensional image of the actual finger vein or fingerprint. In addition, by extracting the feature points for the actual finger vein or fingerprint and using it for user registration and authentication, it is possible to improve the security of electronic devices and implement high resolution finger vein recognition or fingerprint recognition technology based on low-power ultrasound.

In addition, the present invention allows the extinction wave disappearing among the echo waves from the finger through the sound wave control member to be transmitted to the transducer without energy loss, and the signal processing unit stably detects even the signal of the extinction wave to improve the resolution of the image, In the same ultrasonic source as in the prior art, it is possible to obtain a more accurate image than in the prior art, lower the performance of the signal processing unit, and lower power consumption.

1 is a cross-sectional view illustrating a state in which a first node of a finger is used in an electronic device to which a finger biometric information recognition module according to an embodiment of the present invention is applied.
2 is a cross-sectional view illustrating a state in which a second node of a finger is used in an electronic device to which a finger biometric information recognition module according to an embodiment of the present invention is applied.
3 is a schematic cross-sectional view showing a transducer according to an embodiment of the present invention.
Figure 4 is a schematic cross-sectional view showing a sound wave control member according to an embodiment of the present invention.
5 is a block diagram showing a signal processing unit according to an embodiment of the present invention.
6 is a configuration diagram showing an additional configuration of a signal processing unit according to an embodiment of the present invention.
7 is a perspective view showing a finger biometric information recognition module according to another embodiment of the present invention.
8 is an exploded view showing a finger biometric information recognition module according to another embodiment of the present invention.
9 and 10 are cross-sectional views showing a combined state of a finger biometric information recognition module according to another embodiment of the present invention.
11 is a diagram illustrating a method of manufacturing a finger biometric information recognition module according to another embodiment of the present invention.
12 is a flowchart illustrating a method of manufacturing a transducer according to a first embodiment of the present invention.
13 is a flow chart showing the detailed configuration of the thick film manufacturing step in the method of manufacturing a transducer according to the first embodiment of the present invention.
14 is a view showing a modified example of the configuration of the drive slit and filler in the method of manufacturing a transducer according to the first embodiment of the present invention.
15 is a flowchart illustrating a method of manufacturing a transducer according to a second embodiment of the present invention.
16 is a view showing a molding mold and a unit piezoelectric cell in a material release step in a method of manufacturing a transducer according to a second embodiment of the present invention.

Hereinafter, an embodiment of a finger biometric information recognition module, an electronic device to which it is applied, and a manufacturing method of a finger biometric information recognition module and a manufacturing method of a transducer according to the present invention will be described with reference to the accompanying drawings. At this time, the present invention is not limited or limited by the examples. In addition, in describing the present invention, detailed descriptions of known functions or configurations may be omitted to clarify the gist of the present invention.

1 is a cross-sectional view showing a state in which the first node of a finger is used in an electronic device according to an embodiment of the present invention, and FIG. 2 is a state in which a second node of a finger is used in an electronic device according to an embodiment of the present invention 3 is a schematic cross-sectional view showing a transducer according to an embodiment of the present invention, and FIG. 4 is a schematic cross-sectional view showing a sound wave control member according to an embodiment of the present invention. It is a block diagram showing a signal processing unit according to an embodiment of the present invention, Figure 6 is a block diagram showing an additional configuration of a signal processing unit according to an embodiment of the present invention.

1 to 6, the electronic device according to an embodiment of the present invention at least any one of a finger vein and a fingerprint from a finger F through the finger biometric information recognition module 100 according to an embodiment of the present invention By recognizing biometric information containing one, it is possible to enhance the security of the electronic device.

The electronic device according to an embodiment of the present invention includes a finger biometric information recognition module 100 and a main control unit 200.

The finger biometric information recognition module 100 recognizes at least one of a finger vein and a fingerprint from a finger F contacted using ultrasound. As an example, the finger biometric information recognition module 100 detects the first node of the finger F, as shown in FIG. 1, and uses at least one of a finger vein and a fingerprint on the finger F contacted using ultrasound. Can recognize. As another example, the finger biometric information recognition module 100 may recognize a finger vein from the finger F that is contacted by using ultrasonic waves as the second node of the finger F is sensed as illustrated in FIG. 2.

The finger biometric information recognition module 100 will be described in detail in the finger biometric information recognition module 100 according to an embodiment of the present invention.

The main control unit 200 controls the electronic device according to the signal detected by the signal processing unit 20 to be described later included in the finger biometric information recognition module 100.

Here, the main control unit 200 is not limited, and the electronic device may be controlled according to the signal detected by the signal processing unit 20 described later. The main control unit 200 may be connected to the signal processing unit 20 to be described later through an electrode formed in a flip chip bonding or a perforated via hole.

The electronic device according to an embodiment of the present invention may further include a conversion control unit 300. The conversion control unit 300 converts the signal detected by the signal processing unit 20 and transmits it to the main control unit 200. The detailed configuration of the conversion control unit 300 will be described in detail in addition to the description of the finger biometric information recognition module 100 according to an embodiment of the present invention.

Hereinafter, the finger biometric information recognition module 100 according to an embodiment of the present invention will be described.

The finger biometric information recognition module 100 according to an embodiment of the present invention recognizes at least one of a finger vein and a fingerprint from a finger F contacted using ultrasonic waves, and the transducer 10 and a signal processing unit 20, the sound wave control member 40 may be further included. The finger biometric information recognition module 100 according to an embodiment of the present invention mainly describes recognizing a finger vein.

The transducer 10 outputs ultrasonic waves toward the finger F, and receives ultrasonic waves reflected and returned from the finger F. The transducer 10 may be stacked on the signal processing unit 20 or the conversion control unit 300.

Here, the transducer 10 may include a plurality of unit piezoelectric cells 13 arranged vertically and horizontally in a two-dimensional plane, and a filling material 14 filled between the unit piezoelectric cells 13 adjacent to each other. . Here, as the compartment slit 13a is formed between the unit piezoelectric cells 13, the filler 14 is filled in the compartment slit 13a.

In addition, the transducer 10 further includes a lower electrode 11 electrically connected to one side of the unit piezoelectric cell 13 and an upper electrode 15 electrically connected to the other side of the unit piezoelectric cell 13. can do. For example, the lower electrode 11 may be connected to all of the unit piezoelectric cells 13, and the upper electrode 15 may be connected to the individual unit piezoelectric cells 13 in a 1: 1 correspondence. As another example, both the lower electrode 11 and the upper electrode 15 may be connected to the individual unit piezoelectric cells 13 in a 1: 1 correspondence.

The unit piezoelectric cell 13 may improve the characteristics of the ultrasonic signal while facilitating image acquisition corresponding to a finger vein pattern or a fingerprint pattern according to a pitch between the unit piezoelectric cells 13.

The unit piezoelectric cell 13 may exhibit a pillar shape by processing a base material by a dry etching technique or a micro molding technique. In particular, the unit piezoelectric cell 13 may exhibit a shape such as a square pillar, a hexagon pillar, or a cylinder, thereby maximizing power of ultrasonic waves or energy of ultrasonic waves. The transducer 10 may be manufactured by a method of manufacturing a transducer described below.

Then, in the finger biometric information recognition module 100 according to an embodiment of the present invention, the unit piezoelectric cell 13 may include at least one of an inorganic piezoelectric material and an organic piezoelectric material. In one embodiment of the present invention, the unit piezoelectric cell 13 will be described as mixing an inorganic piezoelectric material and an organic piezoelectric material.

Here, the inorganic piezoelectric material has excellent transmission characteristics of ultrasonic waves, and the organic piezoelectric material has excellent ultrasonic reception characteristics. Therefore, the inorganic piezoelectric material is used to improve both ultrasonic transmission characteristics and ultrasonic reception characteristics of the unit piezoelectric cell 13. And the organic piezoelectric material may be mixed in a predetermined weight ratio.

The inorganic piezoelectric material and the organic piezoelectric material may be mixed in a weight ratio of 1: 9 to 9: 1. As described above, due to the mixing of the inorganic piezoelectric material and the organic piezoelectric material, at least the inorganic piezoelectric material is activated in response to the driving signal of the ultrasonic wave to improve the transmission characteristics of the ultrasonic wave, and at least the organic response to the receiving signal of the ultrasonic wave. The piezoelectric material is activated to improve the reception characteristics of ultrasonic waves.

The inorganic piezoelectric material may be made of aluminum nitride (AlN), zirconate titanate (PZT), barium titanate (BaTiO3), and the like, but the piezoelectric properties are relatively inflexible, but the ultrasonic sensing performance is relatively low. The organic piezoelectric material may be made of polyvinylidene fluoride (PVDF), a piezoelectric material made of a soft material or a flexible material, and the piezoelectric properties are relatively poor, but the flexibility is excellent and the impingement matching with the finger (F) It is advantageous.

The transducer 10 manufactured by mixing the organic piezoelectric material and the inorganic piezoelectric material has excellent ultrasonic transmission characteristics and ultrasonic reception characteristics, and thus has a high piezoelectric performance index, and the impedance of the finger F. Advantageously in matching, ultrasonic waves can be stably transmitted even if a separate matching member is omitted between the finger F and the transducer 10.

At this time, in the unit piezoelectric cell 13, a plurality of pores (not shown) communicating with each other are formed in the inorganic piezoelectric material, and the organic piezoelectric material wraps around the outer circumferential surface of the inorganic piezoelectric material or the pores (not shown). Can be formed.

The filling material 14 reduces the horizontal component (lateral mode) perpendicular to the traveling direction of the vibration components generated from the unit piezoelectric cell 13, as well as the vibration between the adjacent unit piezoelectric cells 13 (coupling) can be prevented.

The signal processing unit 20 causes the transducer 10 to output ultrasonic waves, and is electrically connected to the transducer 10 and detects a finger vein of the finger F according to the received ultrasonic waves. The signal processing unit 20 may detect a finger vein of the finger F using a Doppler effect according to the received ultrasound. Here, detecting the finger vein of the finger F includes being able to detect at least one of the finger vein finger and the finger vein fingerprint.

Since the transducer 10 has multiple operating frequencies having excellent piezoelectric characteristics, the signal processing unit 20 can image an arbitrary shape having an ultra fine line width, such as 50 micrometers, in three dimensions. In addition, since the transducer 10 can transmit and receive ultrasonic waves in parallel through the unit piezoelectric cell 13, the signal processing unit 20 can image an arbitrary depth three-dimensional shape.

For example, when the signal processing unit 20 controls the driving signal so that the frequency of the ultrasonic wave output from the transducer 10 represents the first frequency, the first node or the second node of the finger F is detected. Accordingly, the signal processing unit 20 may detect at least one of a finger F and a finger vein. The driving signal generates ultrasonic waves in a low-frequency region to increase the penetration rate of ultrasonic waves and to smoothly detect finger vein of the finger F.

As another example, when the signal processing unit 20 controls the driving signal so that the frequency of the ultrasonic wave output from the transducer 10 is greater than the first frequency, the first node of the finger F As is detected, the signal processing unit 20 may detect the fingerprint of the finger F. The driving signal generates ultrasonic waves in a high-frequency region to relatively lower the penetration rate of ultrasonic waves and facilitate fingerprint detection of the finger F. It can be seen that ultrasonic waves in the low-frequency region have relatively greater power or ultrasonic energy than ultrasonic waves in the high-frequency region.

Here, when the signal processing unit 20 controls the driving signal to output ultrasonic waves from the transducer 10, the signal processing unit 20 receives information on ultrasonic waves received from the transducer 10. By synthesizing, a 3D image of at least one of a finger F and a finger vein may be implemented.

The signal processing unit 20 is connected to the unit piezoelectric cell 13 and the ultrasonic driving unit 21 for applying a driving signal to the unit piezoelectric cell 13 so that the ultrasonic output from the unit piezoelectric cell 13, Multiplexed by being connected to the unit piezoelectric cell 13 and processing an ultrasonic wave received from the unit piezoelectric cell 13 and a specific signal that satisfies a condition among the signals of the ultrasonic processing unit 22 and outputting it It may include a logic unit 23, and a signal conversion unit 24 for converting a signal output from the multiplexing logic unit 23. The ultrasonic processing unit 22 may process the received ultrasonic wave, including a function of restoring the received ultrasonic wave to its original state.

The ultrasonic processor 22 may monitor the received ultrasonic signal and extract the signal for the fingerprint or finger vein from the received ultrasonic signal to correct the received ultrasonic signal.

In more detail, the finger F is composed of the epidermis and the dermis, and in the case of a finger vein, it is located in the subcutaneous tissue. Here, the transducer 10 represents a state in which the unit piezoelectric cells 13 are arranged in a vertical and horizontal direction on a two-dimensional plane.

And the transducer 10 transmits an ultrasonic signal to the finger F, and receives an ultrasonic signal reflected from the finger F. At this time, in the valley portion of the fingerprint, ultrasonic signals reflected from the air layer, the epidermis, the dermis, and the veins are delayed for a certain time and sequentially received in the ultrasonic signal received due to the air layer, and the dermis in the ridge portion of the fingerprint. , The ultrasonic signal reflected from the finger vein is sequentially received with a delay of a certain time. Then, the received ultrasound signals may form image data using a delay and sum method. At this time, since the distortion of the signal due to the air layer occurs in the bone portion of the fingerprint, the ultrasonic processing unit 22 receives information by separating and extracting information about the bone and acid of the fingerprint and information about the finger vein from the received ultrasonic signal. The ultrasonic signal can be corrected, and a 3D image can be easily formed based on the extracted information.

The signal conversion unit 24 may convert a 2D analog signal output from the multiplexing logic unit 23 into a 2D digital signal.

In addition, the signal processing unit 20 controls the driving signal applied from the ultrasonic driving unit 21 so that the frequency of ultrasonic waves is adjusted, and the multiplexing logic with the ultrasonic processing unit 22 in response to the controlled driving signal A signal processing control unit 25 for controlling the operation of the unit 23 and the signal conversion unit 24 may be further included. For example, the signal processing control unit 25 may control an ASIC (Application Specific Integrated Circuit) semiconductor included in the signal processing unit 20.

At this time, the signal processing control unit 25 forms a driving pattern of the unit piezoelectric cell 13 to output ultrasound in response to the driving signal, and the unit piezoelectric cell to receive ultrasound in response to the driving signal The receiving pattern of (13) is formed. Here, the unit piezoelectric cell 13 corresponding to the driving pattern does not overlap with the unit piezoelectric cell 13 corresponding to the reception pattern, thereby preventing signal overlap in the unit piezoelectric cell 13 and preventing signal interference. As much as possible, the unit piezoelectric cell 13 can transmit and receive a signal with high accuracy.

The signal processing unit 20 converts the signal generated by the Hilbert conversion unit 31 and the Hilbert conversion unit 31 to generate a converted signal by Hilbert conversion of the signal converted by the signal conversion unit 24. A shaping unit 32 for shaping to generate a shaping signal, an image replacing unit 33 for replacing the shaping signal generated through the shaping unit 32 with a 3D image element to generate a replacement signal, and a plurality of the A logic synthesis unit 34 for generating a 3D signal by synthesizing the substitution signal generated through the image replacement unit 33 and a final 3D image based on the 3D signal generated through the logic synthesis unit 34 It may include an image acquisition unit 35.

In addition, the final 3D image obtained through the image acquisition unit 35 may be controlled by the main control unit 200 to authenticate the user or be displayed on the electronic device.

In more detail, in one embodiment of the present invention, the signal processing unit 20 is generated based on two different frequencies (A, B) based on the first frequency band or the second frequency band as shown in FIG. High-resolution 3D images can be realized by synthesizing received information.

Then, when the signal processing control unit 25 controls the driving signal to display a primary frequency transmission signal having a frequency of ultrasonic waves output from the transducer and a secondary frequency transmission signal greater than the primary frequency transmission signal, the The signal processing unit 20 synthesizes first reception information corresponding to the primary frequency transmission signal and second reception information corresponding to the secondary frequency transmission signal to implement a 3D image.

The Hilbert conversion unit 31 and the first Hilbert conversion unit (31a) for generating a first conversion signal by Hilbert conversion of the first signal converted by the signal conversion unit 24 in response to the first received information, The second signal converted by the signal conversion unit 24 in accordance with the second reception information may be classified into a second Hilbert conversion unit 31b that performs Hilbert conversion to generate a second conversion signal.

The shaping unit 32 is a first shaping unit 32a for shaping the first conversion signal generated through the first Hilbert conversion unit 31a to generate a first shaping signal, and the second Hilbert conversion unit ( The second conversion signal generated through 31b) can be normalized to be divided into a second shaping unit 32b that generates a second shaping signal.

The image replacement unit 33 is a first image replacement unit 33a for generating a first replacement signal by replacing the first normalization signal generated through the first normalization unit 32a with a three-dimensional image element, and The second shaping signal generated through the second shaping unit 32b may be divided into a second image replacing unit 33b that generates a second replacement signal by substituting a 3D image element.

The logic synthesizing unit 34 synthesizes a 3D digital signal by synthesizing a first replacement signal generated through the first image replacement unit 33a and a second replacement signal generated through the second image conversion unit 33b. Will be created.

The signal processing unit 20 is a signal synthesis technology optimized for the unit piezoelectric cells 13 arranged in two dimensions, and can implement a low power and high efficiency 3D image algorithm. The signal processing unit 20 collects hybrid micropatterns having a line width of 50 microns or a line width of 100 microns in parallel to enable high-speed three-dimensional imaging, and the unit piezoelectric cells 13 arranged in two dimensions in the transducer 10 ) Can be integrally controlled with the driver and receiver.

As described above, in the finger biometric information recognition module 100 according to an embodiment of the present invention, the transducer 10 may implement a hybrid ultrasonic element array having multiple operating frequencies together with the signal processing unit 20. Then, an arbitrary shape having a fine line width of 50 microns, which is superior to the conventional one, can be three-dimensionally imaged with a high-frequency ultrasonic element. In addition, by imaging an arbitrary three-dimensional shape in depth through a low frequency received in parallel, it activates an imaging function using ultrasound, can easily implement a three-dimensional finger vein imaging, and greatly improve security in electronic devices. have.

The finger biometric information recognition module 100 according to an embodiment of the present invention may further include a sound wave control member 40.

The sound wave control member 40 is stacked on the transducer 10. The sound wave control member 40 allows ultrasonic energy transmitted and received from the transducer 10 to be transmitted without loss.

The sound wave control member 40 may represent a waveguide structure that transmits ultrasonic energy transmitted and received from the unit piezoelectric cell 13 without loss.

The sound wave control member 40 may absorb near-field ultrasonic waves with respect to the generated ultrasonic waves in a specific frequency region, and exhibit characteristics of resonating and transmitting ultrasonic energy using characteristics such as resonance tunneling.

Accordingly, the sound wave control member 40 can transmit ultrasonic energy without loss, and can also image ultrasonic waves of a wavelength or less.

The sound wave control member 40 may use a Helmholtz resonator array structure, surface resonant effect in doubly negative or single negative-mass metamaterials, FabryPerot (FP) resonant, Near-zero mass, resonant tunneling method of anisotropic meta materials, and the like.

The sound wave control member 40 includes a first signal transmission groove 41 that is recessed on one side facing the transducer 10, and a second signal transmission groove that is recessed on the other side opposite to one side ( 42) and a connection line 43 connecting the first signal transmission groove 41 and the second signal transmission groove 42. Then, the first signal transmission groove 41 is recessed on one side of the sound wave control member 40, and the second signal transmission groove 42 is recessed on the other side of the sound wave control member 40. do.

At this time, the sound wave control member 40 has a control matching member 45 to be filled therein. In other words, the acoustic impedance between the transducer 10 and the finger F is matched to the first signal transmission groove 41 and the second signal transmission groove 42 and the connection line 43. The control mating member 45 is filled.

The control matching member 45 may be used when the sound wave control member 40 operates in a liquid. In other words, the control matching member 45 is substantially the acoustic impedance of the finger (F) or the acoustic impedance of blood or tissue in the finger to substantially prevent energy loss of ultrasonic waves transmitted and received from the transducer (10). Try to have the same acoustic impedance.

The control matching member 45 may increase the transmittance of ultrasonic waves in the sound wave control member 40.

In one embodiment of the present invention, the first signal transmission groove 41 and the second signal transmission groove 42 have the same diameter as each other, and the first signal transmission groove 41 is the connection line 43 of the It can be formed larger than the diameter.

In addition, the sound wave control member 40 may further include a buffer space 44 formed on the connection line 43 having a different diameter from the connection line 43. For example, the buffer space 44 may have a larger diameter than the diameter of the connecting line 43. The control unit 45 is filled in the buffer space 44.

The sound wave control member 40 may be manufactured by at least one selected from a MEMS process, a NEMS process, a 3D printing process, a nano-imprinting process, and an injection process.

The finger biometric information recognition module 100 according to an embodiment of the present invention may further include a contact member 50 stacked on the sound wave control member 40 so that the finger F contacts.

The finger F is in contact with the contact member 50. The contact member 50 may be made of glass, aluminum, sapphire, plastic, or the like. The contact member 50 transmits ultrasonic waves to the finger F, and transmits ultrasonic waves returning from the finger F to the transducer 10 side.

The contact member 50 may be integrally formed with a touch screen device provided in an electronic device or a display device for outputting a screen. The contact member 50 may be used as a cover attached to the front of a touch screen device or a display device.

The finger biometric information recognition module 100 according to an embodiment of the present invention may further include a transfer matching member 60 stacked and supported between the sound wave control member 40 and the contact member 50. The contact member 50 and the transfer matching member 60 match the acoustic impedance between the transducer 10 and the finger F.

For example, the transmission matching member 60 may facilitate transmission of ultrasound waves through the second signal transmission groove 42 between the sound wave control member 40 and the contact member 50. In more detail, it is possible to prevent the air layer between the control mating member 45 and the contact member 50 from being formed, and to facilitate the transmission of ultrasonic waves.

As another example, the transmission matching member 60 may connect the sound wave control member 40 and the contact member 50 to each other.

Hereinafter, an operation of the finger biometric information recognition module 100 according to an embodiment of the present invention will be described.

In the finger biometric information recognition module 100 according to an embodiment of the present invention, the signal processing unit 20, the transducer 10, the sound wave control member 40, and the contact member 50 are sequentially stacked. Is fixed. At this time, the sound wave control member 40 is filled with the control matching member 45.

Since the size of blood vessels is 200 microns to 1000 microns with respect to the finger vein pattern of the finger F, and the period of adjacent bones and floors with respect to the fingerprint pattern of the finger F is about 200 microns to 300 microns, pattern image resolution Needs about 50 microns. Here, the impedance for the inorganic piezoelectric material is about 30 Mrayl, but the organic piezoelectric material has an impedance characteristic similar to that of the finger F (about 1.5 Mrayl), so even if a separate mating member is omitted, the transducer In (10), the transmission / reception characteristics of ultrasonic waves can be maintained.

 Then, the transducer 10 is measured using the magnitude of the reflected wave returned from the finger F and the transmitted wave determined by the impedance (density of the object and the sound wave propagation velocity of the object).

The ultrasonic waves generated from the transducer 10 and the reflected waves returning from the finger F are almost 100% (90% to 100% or 95% to 100%) due to resonance while passing through the sound wave control member 40. It has a transmitted frequency.

In addition, a three-dimensional image may be implemented by using a time delay value in the echo wave input to the transducer 10 or the conversion of the echo wave through the signal processing unit 20. In one embodiment of the present invention, the extinction wave passes through the sound wave control member 40 and is transmitted to the transducer 10 without loss of ultrasonic energy, thereby facilitating a three-dimensional image.

Based on the above description, the conversion control unit 300 transmits the signal detected by the signal processing unit 20 to the main control unit 200. The conversion control unit 300 may convert the signal converted by the signal conversion unit 24 into an output signal that can be output from an electronic device and transmit the converted signal to the main control unit 200.

The conversion control unit 300 may be respectively connected to the signal processing unit 20 and the main control unit 200 through electrodes formed in flip chip bonding or perforated via holes.

Although not shown, the conversion control unit 300 may synthesize received information for two different frequency domains A and B on behalf of the signal processing unit 20 to implement a high-resolution 3D image. Accordingly, the conversion control unit 300 replaces the signal processing unit 20, the Hilbert conversion unit 31, the shaping unit 32, the image replacement unit 33, the logic synthesis unit ( 34) and an image acquisition unit 35.

In addition, the final 3D signal obtained through the image acquisition unit 35 may be controlled by the main control unit 200 to authenticate the user or be displayed on the electronic device.

Accordingly, the conversion control unit 300 is also a signal synthesis technology optimized for the unit piezoelectric cells 13 arranged in two dimensions, and it is possible to implement a low-power and high-efficiency three-dimensional image algorithm.

Hereinafter, the finger biometric information recognition module 100 according to another embodiment of the present invention will be described.

Figure 7 is a perspective view showing a finger biometric information recognition module according to another embodiment of the present invention, Figure 8 is an exploded view showing a finger biometric information recognition module according to another embodiment of the present invention, Figures 9 and 10 It is a cross-sectional view showing a combined state of a finger biometric information recognition module according to another embodiment of the present invention.

1 to 6 and 7 to 10, the finger biometric information recognition module 100 according to another embodiment of the present invention includes at least one of a finger vein and a fingerprint from a contacted finger F A finger biometric information recognition module for recognizing biometric information, the transducer 10 outputting ultrasonic waves toward the finger F and receiving ultrasonic waves reflected and returned from the finger F, and the transducer 10 ) Includes a signal processing unit 20 that outputs ultrasound and is electrically connected to the transducer 10 and detects bio-information of the finger F according to the received ultrasound. A sound wave control member 40 stacked on the transducer 10 to be transmitted may be further included.

The signal processing unit 20 and the sound wave control member 40 according to another embodiment of the present invention have the same configuration as the signal processing unit 20 and the sound wave control member 40 according to an embodiment of the present invention Therefore, the description thereof will be omitted.

At this time, the transducer 10 may include a plate-shaped piezoelectric plate 16 that outputs ultrasonic waves toward the finger F. The piezoelectric plate 16 may include aluminum nitride (AlN) or lead zirconate titanate (PZT, PbZrTiO3).

The transducer 10 further includes a lower electrode 11 electrically connected to one side of the piezoelectric plate 16 and an upper electrode 15 electrically connected to the other side of the piezoelectric plate 16. can do. In another embodiment of the present invention, the lower electrode 11 is connected to the piezoelectric plate 16 in a state arranged vertically and horizontally in a two-dimensional plane corresponding to a unit cell, and the upper electrode 15 is in the form of a plate. It is connected to the piezoelectric plate.

Finger biometric information recognition module 100 according to another embodiment of the present invention is the transducer 10 and the sound wave control member 40 so that ultrasound is transmitted between the transducer 10 and the sound wave control member 40 ) It may further include an ultrasonic transmission member 70 that is inserted and stacked between. Here, a support portion 71 may be stacked and supported on the ultrasonic transmission member 70. The support part 71 may improve the bonding force between the transducer 10 and the ultrasonic transmission member 70 and stably support the transducer 10 in the ultrasonic transmission member 70.

A transmission hole through which ultrasonic waves are transmitted may be formed in the ultrasonic transmission member 70 in correspondence with the unit cell or the piezoelectric plate 16. Then, the ultrasonic transmission member 70 may represent a waveguide structure that transmits ultrasonic energy transmitted and received from the piezoelectric plate 16 without loss. The ultrasonic transmission member 70 absorbs near-field ultrasonic waves with respect to the generated ultrasonic waves in a specific frequency region, and may exhibit characteristics of resonating and transmitting ultrasonic energy using characteristics such as resonance tunneling.

At this time, the hole formed through the ultrasonic transmission member 70 is filled with an impedance layer 72 to reduce the difference in acoustic impedance between the finger F and the transducer 10, and the finger F and the The acoustic impedance between the transducers 10 can be matched.

The finger biometric information recognition module 100 according to another embodiment of the present invention is in a vacuum state between the transducer 10 and the signal processing unit 40 to prevent ultrasonic waves from being transmitted to the signal processing unit 20. It may further include a post member 80 for forming a space of. The post member 80 may be laminated and fixed to the signal processing unit 20 via an adhesive portion 81. The adhesive portion 81 may exhibit conductivity for electric transmission, but may be non-conductive.

Here, a space portion 82 is formed through the post member 80 in correspondence with the unit cell or the piezoelectric plate 16. When the transducer 10, the post member 80 and the signal processing unit 20 are stacked and coupled, the space portion 82 forms a vacuum state, thereby generating ultrasonic waves generated in the transducer 10 Alternatively, the ultrasonic wave received by the transducer 10 may be prevented from being transmitted to the signal processing unit 20, and the signal processing unit 20 may be protected from the ultrasonic signal. In addition, the post member 80 and the adhesive portion 81 may have a buffer function to prevent ultrasonic waves from being transmitted to the signal processing unit 20.

The space portion 82 may also be formed on the adhesive portion 81 corresponding to the shape of the post member 80.

A non-explanatory reference numeral 73 is a protective layer 73 for protecting the ultrasonic transmission member 70 when manufacturing the finger biometric information recognition module 100 according to another embodiment of the present invention. The protective layer 73 may be removed from the ultrasound transmission member 70 in the process of manufacturing the finger biometric information recognition module 100.

Hereinafter, a method of manufacturing a finger biometric information recognition module 100 according to another embodiment of the present invention will be described.

11 is a diagram illustrating a method of manufacturing a finger biometric information recognition module according to another embodiment of the present invention.

Referring to FIG. 11, a method of manufacturing a finger biometric information recognition module according to another embodiment of the present invention is a method of manufacturing a finger biometric information recognition module according to another embodiment of the present invention.

For example, in the method of manufacturing a finger biometric information recognition module according to another embodiment of the present invention, the transducer 10 and the ultrasonic transmission member 70 may be stacked on the signal processing unit 20.

First, a transmission base material 70a for forming the ultrasonic transmission member 70 is prepared. At this time, the support portion 71 and the protective layer 73 may be formed on the upper and lower surfaces of the transfer base material 70a. The support portion 71 may be formed on the upper surface of the transfer base material 70a.

Then, the upper electrode 15, the piezoelectric plate 16, and the lower electrode 11 are stacked in the form of a plate on the transfer base material 70a. The upper electrode 15, the piezoelectric plate 16, and the lower electrode 11 are sequentially stacked and fixed to the transfer base material 70a.

Next, the lower electrode 11 is etched so that the lower electrode 11 in the form of a plate is separated corresponding to the unit cell. The lower electrode 11 may be etched by various types of wet etching or dry etching.

Next, a via hole for electrical connection with the upper electrode 15 is formed on the piezoelectric plate 16, and connection is made to apply power to the upper electrode 15 and the separated lower electrode 11, respectively. The transducer 10 is formed by patterning the line 111.

Next, the transducer 10 integrally formed on the transmission base material 70a is stacked on the signal processing unit 20 so that the signal processing unit 20 and the connection line 111 are electrically connected.

Here, a post member 80 is prevented from being transmitted to the signal processing unit 20 to prevent ultrasonic waves from being transmitted to the signal processing unit 20. And the post member 80 stacked on the signal processing unit 20, the transducer 10 is integrally formed in the transmission base material 70a in a vacuum atmosphere to form the vacuum portion 82 To be stacked on.

Lastly, the ultrasonic transmission member 70 is formed by processing the transmission base material 70a. The ultrasonic transmission member 70 may be formed through the transmission base material 70a by removing the protective layer 73 as well as punching the transmission hole in the transmission base material 70a.

In addition to this, the sound wave control member 40 may be stacked on the ultrasonic transmission member 70.

Through the series of processes described above, a finger biometric information recognition module according to another embodiment of the present invention may be manufactured.

As another example, in the method of manufacturing a finger biometric information recognition module according to another embodiment of the present invention, the transducer 10 and the sound wave control member 40 may be stacked on the signal processing unit 20.

First, a base for stacking the upper electrode 15 is prepared.

Then, the upper electrode 15, the piezoelectric plate 16, and the lower electrode 11 are stacked on the base in the form of a plate. The upper electrode 15, the piezoelectric plate 16, and the lower electrode 11 are sequentially stacked and fixed to the sound wave control member 40.

Next, the lower electrode 11 is etched so that the lower electrode 11 in the form of a plate is separated corresponding to the unit cell. The lower electrode 11 may be etched by various types of wet etching or dry etching.

Next, a via hole for electrical connection with the upper electrode 15 is formed on the piezoelectric plate 16, and connection is made to apply power to the upper electrode 15 and the separated lower electrode 11, respectively. The transducer 10 is formed by patterning the line 111.

Next, the transducer 10 is stacked on the signal processing unit 20 so that the signal processing unit 20 and the connection line 111 are electrically connected.

Here, a post member 80 is prevented from being transmitted to the signal processing unit 20 to prevent ultrasonic waves from being transmitted to the signal processing unit 20. In addition, the spacer 82 is stacked on the post member 80 stacked on the signal processing unit 20 in a vacuum atmosphere to form a vacuum state, so that the spacer 82 is formed. To form a vacuum.

Finally, the sound wave control member 40 is stacked on the transducer 10.

Through the series of processes described above, a finger biometric information recognition module according to another embodiment of the present invention may be manufactured.

Here, the base may be provided separately from the base, and may be separated from the transducer 10 before laminating the sound wave control member 40 to the transducer 10.

In addition, the base may be provided with the sound wave control member 40. In this case, the support portion 71 and the protective layer 73 may be formed on the upper and lower surfaces of the sound wave control member 40. The support portion 71 may be formed on the upper surface of the sound wave control member 40. Then, the process of stacking the sound wave control member 40 on the transducer 10, which is the last process, is omitted.

Hereinafter, a method of manufacturing the transducer according to the first embodiment of the present invention will be described.

12 is a flowchart illustrating a method of manufacturing a transducer according to a first embodiment of the present invention, and FIG. 13 shows a detailed configuration of a thick film manufacturing step in the method of manufacturing a transducer according to the first embodiment of the present invention 14 is a view showing a modification of the configuration of the driving slit and the filling material in the method of manufacturing the transducer according to the first embodiment of the present invention.

1 to 6 and 12 to 14, the manufacturing method of the transducer according to the first embodiment of the present invention by forming the unit piezoelectric cell 13 using a dry etching technique, the transducer It is a method of manufacturing (10).

The manufacturing method of the transducer according to the first embodiment of the present invention comprises a thick film manufacturing step (S11) of mixing the inorganic piezoelectric material and the organic piezoelectric material to produce a composite piezoelectric film (10a), and the composite piezoelectric film (10a). ) In the thick film cutting step (S12) of cutting the composite piezoelectric thick film (10a) manufactured through the thick film manufacturing step (S11) so that the partition slit (13a) is recessed, and the partition slit (13a) It may include a slit filling step (S13) for filling the filling material (14). In the slit filling step (S13), the filling material 14 may be sintered.

Here, in the thick film manufacturing step (S11), pores may be formed in the inorganic piezoelectric material, and then the inorganic piezoelectric material and the organic piezoelectric material having pores may be mixed to form the composite piezoelectric thick film 10a.

In the thick film manufacturing step (S11), a template stacking step of stacking a template for forming pores (not shown) on the base, and after passing through the temple stacking step (S11a), impregnating the precursor with the precursor of the inorganic piezoelectric material The precursor solution impregnation step (S11b), and the precursor solution impregnation step (S11b), followed by a drying step (S11c) of drying the precursor solution of the inorganic piezoelectric material, and the drying step (S11c), followed by drying. A de-templing step (S11d) for removing the template from the precursor of the inorganic piezoelectric material, and a crystallization step (S11e) for crystallizing the dried precursor of the inorganic piezoelectric material after passing through the de-templing step (S11d), and After the crystallization step (S11e), an organic material input step (S11f) of introducing the organic piezoelectric material into the precursor solution of the inorganic piezoelectric material crystallized, and the precursor and the organic piezoelectric material of the crystallized inorganic piezoelectric material are mixed. castle And it may comprise a thickening step (S11g) for producing the composite piezoelectric thick film (10a).

The precursor solution of the inorganic piezoelectric material dried according to the step of removing the temple (S11d) forms pores (not shown) as the final completed inorganic piezoelectric material to form a porous body.

In addition, in the step of introducing the organic material (S11f), the organic piezoelectric material is introduced into a precursor solution of the inorganic piezoelectric material dried according to a predetermined mixing ratio of the inorganic piezoelectric material and the organic piezoelectric material. In addition, as the organic material introduction step (S11f) and the thickening step (S11g), the organic piezoelectric material wraps the outer circumferential surface of the dried precursor solution of the inorganic piezoelectric material, or is formed in the pores (not shown). Can be.

In the method of manufacturing the transducer according to the first embodiment of the present invention, as the thick film cutting step (S12) is performed, the composite piezoelectric film 10a has a plurality of unit piezoelectric cells 13 spaced apart from each other on the base layer. Arranged in the vertical and horizontal, the partition slit 13a is formed between adjacent unit piezoelectric cells 13. Then, after the slit filling step (S13), the base layer may be removed to finally complete the transducer 10.

In the first embodiment of the present invention, the unit piezoelectric cell 13 increases the number of the unit piezoelectric cells 13 per unit area by increasing the diameter from the base layer to the free end, thereby improving the resolution of ultrasonic waves. have.

In the first embodiment of the present invention, the resolution of the ultrasonic wave is 500 dpi or more, so that the high-resolution ultrasonic transducer 10 can be implemented.

In addition, in the modification of the first embodiment of the present invention, as the thick film cutting step (S12) and the slit filling step (S13) are repeated two or more cycles, the unit piezoelectric cell ( 13) can be prevented from falling off.

In the first embodiment of the present invention, a method of manufacturing a transducer according to a modified example primarily comprises the thick film manufacturing step (S11) and the unit piezoelectric cell 13, using the composite piezoelectric film 10a as an etching technique. A first cutting step (S12a) for cutting, a first filling step (S13a) for filling the filling material 14 in the partition slit 13a formed by the first cutting step (S12a), and the unit piezoelectric cell In response to (13), the second cutting step (S12b) of cutting the composite piezoelectric film 10a by an etching technique, and the filling material in the partition slits 13a formed by the second cutting step (S12b) (14) a second filling step (S13b) of filling, and additionally in response to the unit piezoelectric cell 13, the third cutting step of cutting the composite piezoelectric film 10a by an etching technique thirdly ( S12c) and a third filling stage for filling the filling material 14 in the partition slit 13a formed by the third cutting step (S12c). A (S13c) may further include.

Here, the manufacturing method of the transducer according to the modification of the first embodiment of the present invention is subjected to the second filling step (S13b) or the third filling step (S13c), and then removing the base layer to remove the transducer ( 10) can be finalized.

The manufacturing method of the transducer according to the first embodiment of the present invention may further include an electrode forming step (S3).

In the electrode forming step (S3), the lower electrode 11 and the upper electrode 15 are formed on both sides of the composite piezoelectric film 10a to apply power to the transducer 10, respectively.

The electrode forming step (S3) is a lower electrode forming step (S31) of forming the lower electrode 11 on one side of the composite piezoelectric film 10a, and the upper side of the other side of the composite piezoelectric film 10a. It can be divided into an upper electrode forming step (S32) to form the electrode 15.

For example, the lower electrode forming step (S31) and the upper electrode forming step (S32) may be performed after passing through the slit filling step (S13), respectively.

As another example, the lower electrode forming step (S31) and the upper electrode forming step (S32) may be performed after passing through the thick film manufacturing step (S11), respectively.

As another example, one of the lower electrode forming step (S31) and the upper electrode forming step (S32) is carried out after the thick film manufacturing step (S11), and the lower electrode forming step (S31) and the upper electrode Another of the forming step (S32) may be carried out after passing through the slit filling step (S13).

The transducer 10 manufactured according to the first embodiment of the present invention may be connected to the signal processing unit 20 or the conversion control unit 300 in a completed state.

In addition, the transducer 10 manufactured according to the first embodiment of the present invention has the thick film in a state in which the composite piezoelectric film 10a is connected to the signal processing unit 20 or the conversion control unit 300. The cutting step (S12) and the slit filling step (S13) may be performed.

Hereinafter, a method of manufacturing the transducer according to the second embodiment of the present invention will be described.

15 is a flow chart showing a method of manufacturing a transducer according to a second embodiment of the present invention, and FIG. 16 is a molding mold and a unit in a material release step in the method of manufacturing a transducer according to the second embodiment of the present invention It is a diagram showing a piezoelectric cell.

1 to 6 and 15 and 16, the method of manufacturing the transducer according to the second embodiment of the present invention by forming the unit piezoelectric cell 13 using a micro-molding technique, the transducer It is a method of manufacturing (10).

The manufacturing method of the transducer according to the second embodiment of the present invention includes a material preparation step (S21), a molding mold preparation step (S22), a green array manufacturing step (S25), and a sintered array manufacturing step (S26), It may include an array release step (S27), an array filling step (S28), a base layer removal step (S29), and an electrode forming step (S3).

In the material preparation step (S21), the inorganic piezoelectric material or the organic piezoelectric material or a mixed material obtained by mixing the inorganic piezoelectric material and the organic piezoelectric material is prepared. The inorganic piezoelectric material or the organic piezoelectric material or the mixed material may exhibit a liquid or paste state. Here, the inorganic piezoelectric material may form pores (not shown) through the steps from the temple lamination step (S11a) to the crystallization step (S11e) of the thick film production step (S11).

In the molding mold preparation step (S22), a molding mold 400 having a cell groove 411 corresponding to the unit piezoelectric cell 13 is prepared. The molding mold 400 is a first mold 410 in which the cell groove 411 corresponding to the unit piezoelectric cell 13 is recessed, and the organic piezoelectric material or the inorganic piezoelectric material or the mixed material is injected The hole 421 includes a second mold 420 through which it is formed. The first mold 410 and the second mold 420 are stacked and supported, and the second mold 420 can be moved up and down in relative motion with respect to the first mold 410. Here, a base groove 412 for forming a base layer 12 in which the unit piezoelectric cell 13 is arranged may be recessed in at least one of the first mold 410 and the second mold 420. have.

The molding mold preparation step (S22) is a master preparation step (S23) in which the unit piezoelectric cells 13 are spaced apart from each other in the base layer 12 to prepare a master mold made of a hard material in correspondence with the vertical and horizontal arrangement. It may include a soft manufacturing step (S24) for manufacturing a soft mold of a flexible material or a soft material using the master mold. Here, the soft mold may have the same shape as the first mold 410 in which the cell groove 411 corresponding to the unit piezoelectric cell 13 is recessed among the molding mold 400.

The master mold is made of a hard material such as silicon, and thus it is easy to manufacture a protrusion shape corresponding to the unit piezoelectric cell 13, and the soft mold is made of a soft material such as silicone oil (PDMS, polydimethylsiloxane) or a flexible material. The cell groove 411 may be stably manufactured in correspondence with a protrusion shape formed in the master mold.

In the green array manufacturing step (S25), the unit piezoelectric cell 13 is formed on the base layer 12 by injecting the organic piezoelectric material or the inorganic piezoelectric material or the mixed material into the molding mold 400 ( Prepare 10b). In the green array manufacturing step (S25), the organic piezoelectric material or the inorganic piezoelectric material or the mixed material is inserted into the injection hole 421 while the first mold 410 and the second mold 420 are bonded. By injecting the injected material to fill the cell groove 411 and the base groove 412, the green array 10b can be manufactured.

In the sintered array manufacturing step (S26), the green array 10b is sintered to manufacture a sintered array. The sintered array manufacturing step (S26) may sinter the green array 10b using various types of sintering techniques.

In the array release step (S27), the green array 10b or the sintered array is separated from the molding mold 400.

In the array filling step (S27), a filling material 14 is filled between the unit piezoelectric cells 13 adjacent to each other in the sintered array. The filling material 14 is sintered so as to be integral with the unit piezoelectric cell 13.

The base layer removing step (S29) removes the base layer from the sintered array filled with the filler 14 so that only the unit piezoelectric cell 13 and the filler 14 remain in the sintered array.

In the electrode forming step (S3), the lower electrode 11 and the upper electrode 15 are formed on both sides of the sintered array where the base layer 12 is removed to apply power to the transducer 10, respectively. do.

The electrode forming step (S3) is a lower electrode forming step (S31) of forming the lower electrode 11 on one side of the sintered array from which the base layer 12 is removed, and the base layer 12 is removed. It can be divided into an upper electrode forming step (S32) for forming the upper electrode 15 on the other side of the sintered array.

For example, the lower electrode forming step (S31) and the upper electrode forming step (S32) may be performed after passing through the base layer removing step (S29), respectively.

As another example, the lower electrode forming step (S31) and the upper electrode forming step (S32) may be performed after passing through the array filling step (S27), respectively.

As another example, one of the lower electrode forming step (S31) and the upper electrode forming step (S32) is performed after the array filling step (S27), and the lower electrode forming step (S31) and the upper electrode The other of the forming step (S32) may be carried out after passing through the base layer removing step (S29).

The manufacturing method of the transducer according to the second embodiment of the present invention is to manufacture the sintered array in which the unit piezoelectric cell 13 is formed on the base layer 12, and fill the sintered array with the filling material 14, The transducer 10 can be manufactured. The transducer 10 manufactured according to the second embodiment of the present invention may be connected to the signal processing unit 20 or the conversion control unit 300 in a completed state.

In the second embodiment of the present invention, the cell groove 411 formed in the molding mold 400 has a smaller diameter as it goes from the inlet to the inside, so that the diameter of the unit piezoelectric cell 13 goes from the base layer to the free end. You can lose. Then, the number of the unit piezoelectric cells 13 per unit area can be increased, and the resolution of ultrasonic waves can be improved.

In the second embodiment of the present invention, the resolution of the ultrasonic wave is 500 dpi or more, so that the high-resolution ultrasonic transducer 10 can be implemented.

According to the above-described finger biometric information recognition module, an electronic device to which it is applied, and a manufacturing method of a finger biometric information recognition module and a manufacturing method of a transducer, the characteristics of the transducer 10 are changed, so that the finger using ultrasonic waves When recognizing biometric information such as a finger vein or fingerprint of (F), the recognition rate of ultrasonic waves may be increased, and the precision for recognizing biometric information of the finger F may be improved.

In addition, the acoustic impedance between the transducer 10 and the finger F can be stably matched by changing the characteristics of the transducer 10, and a separate matching member can be omitted.

In addition, among the vibration components generated in the unit piezoelectric cell 13, the horizontal component perpendicular to the traveling direction of the ultrasonic wave is reduced, as well as vibration interference between adjacent unit piezoelectric cells 13 is prevented. It is possible to individually drive and individually receive the unit piezoelectric cell 13, and the unit piezoelectric cell 13 can simultaneously improve the transmission characteristics of ultrasonic waves and the reception characteristics of ultrasonic waves.

In addition, the driving signal of the ultrasonic wave and the receiving signal of the ultrasonic wave are separated from the unit piezoelectric cell 13, so that the transmitting characteristics of the ultrasonic wave and the receiving characteristics of the ultrasonic wave can be improved at the same time.

In addition, the unit piezoelectric cell 13 simplifies the combination of the inorganic piezoelectric material and the organic piezoelectric material to simplify the manufacturing of the transducer 10, as well as the power of ultrasonic waves in the unit piezoelectric cell 13 or It is possible to prevent energy loss of ultrasonic waves and improve skin penetration rate of ultrasonic waves.

In addition, both the ultrasonic wave transmitted through the transducer 10 and the sound wave control member 40 and the received ultrasonic wave are transmitted without energy loss, thereby improving the transmission / reception sensitivity of the ultrasonic wave, the transmittance of the ultrasonic wave and the reflectance of the reflected wave, and The transmission power of the evanescent wave is improved, the acoustic impedance between the transducer 10 and the finger F is stably matched, and a separate matching member can be omitted.

In addition, through the sound wave control member 40, the extinction wave having a smaller wavelength and amplitude can be stably received from the transducer 10 and stably transmitted to the signal processing unit 20.

In addition, the ultrasonic wave input from the sound wave control member 40 is stably guided in the traveling direction, the ultrasonic wave is induced from the sound wave control member 40, and the ultrasonic waves input are transmitted without loss of energy, so that the contact is made. It is possible to stabilize the transmission of ultrasonic waves between the member 50 and the signal processing unit 20.

In addition, by filling the control mating member 45 in a portion formed through the sound wave control member 40, the attenuation of ultrasonic waves is prevented, the transmission of ultrasonic waves is stabilized, and the acoustic impedance with a finger is stably matched. You can.

In addition, as the frequency of the ultrasound is adjusted, the finger F can recognize the finger vein and the fingerprint, and the finger F can accurately capture the flow of the finger vein, fingerprint, etc. ), A 3D image of a finger vein or fingerprint can be implemented.

In addition, it is possible to improve security according to the recognition of a fingerprint or a finger vein in an electronic device and protect personal information embedded in the electronic device.

In addition, it implements micrometer-level micro-processing to control the sound in the ultrasonic region, facilitates the manufacture of the sound wave control member 40, improves the strength of the structure of the sound wave control member 40, , It can increase the supporting or supporting power of the structure.

In addition, centering between the first signal transmission groove 41 and the second signal transmission groove 42 and the connection line 43 formed in the sound wave control member 40 is simplified, and stacking errors are minimized. The failure of the sound wave control member 40 can be prevented.

In addition, the height of the sound wave control member 40 can be reduced, and it can contribute to miniaturization and thinning of the finger biometric information recognition module 100.

In addition, even if there is a contaminant (dust, sweat, residual cosmetics, etc.) on the finger F, imaging of the finger vein or fingerprint is possible, and the material of the contact member 50 to which the finger F is contacted (glass, Regardless of aluminum, sapphire, plastic, etc.), the signal processing unit 20 can recognize a finger vein or fingerprint, and can facilitate the design of the finger biometric information recognition module 100 in an electronic device.

In addition, it is possible to obtain a high-resolution three-dimensional image of the actual finger vein or fingerprint. In addition, by extracting the feature points for the actual finger vein or fingerprint and using it for user registration and authentication, it is possible to improve the security of electronic devices and implement high resolution finger vein recognition or fingerprint recognition technology based on low-power ultrasound.

In addition, through the sound wave control member 40, the vanishing wave disappearing among the echo waves in the finger F is transmitted to the transducer 10 without energy loss, and the signal processing unit 20 uses the vanishing wave. It is possible to stably detect even the signal to improve the resolution of the image, obtain a more accurate image than the prior art in the same ultrasonic source, lower the performance of the signal processing unit 20, and lower power consumption. have.

Although the preferred embodiments of the present invention have been described with reference to the drawings as described above, those skilled in the art may vary the present invention without departing from the spirit and scope of the present invention as set forth in the claims below. It can be modified or changed.

F: Finger 100: Finger biometric information recognition module 200: Main control unit
300: conversion control unit 10: transducer 10a: composite piezoelectric thick film
10b: Green array. 11: lower electrode 111: connection line
12: base layer 13: unit piezoelectric cell 14: compartment slit
15: upper electrode 16: piezoelectric plate 20: signal processing unit
21: ultrasonic driving unit 22: ultrasonic processing unit 23: multiplexing logic unit
24: signal conversion unit 25: signal processing control unit 31: Hilbert conversion unit
32: shaping part 33: image replacement part 34: logical synthesis part
35: image acquisition unit 40: sound wave control member 41: first signal transmission unit
42: second signal transmission unit 43: connection line 44: buffer space
45: control matching member 50: contact member 60: transmission matching member
70: ultrasonic transmission member 70a: transmission base material 71: support
72: impedance layer 80: post 81: adhesive portion
82: space 400: forming mold 410: first mold
411: Cell groove 412: Base groove 420: Second mold
421: Injection hole S11: Thick film production step S11a: Temple stacking step
S11b: Pre-impregnation step S11c: Drying step S11d: Tamper removal step
S11e: Crystallization step S11f: Organic material injection step S11g: Thickening step
S12: Thick film foundation step S12a: First foundation step S12b: Second foundation step
S12c: Third foundation step S13: Slit filling step S13a: First filling step
S13b: Second filling step S13c: Third filling step S21: Material preparation step
S22: Molding mold preparation step S23: Master preparation step S24: Soft manufacturing step
S25: Green array manufacturing step S26: Sintered array manufacturing step
S27: Array release step S28: Array filling step
S29: base layer removal step S3: electrode formation step
S31: lower electrode forming step S32: upper electrode forming step

Claims (16)

A finger biometric information recognition module for recognizing biometric information including at least one of a finger vein and a fingerprint from a finger in contact,
A transducer that outputs ultrasonic waves toward the finger and receives ultrasonic waves reflected and returned from the finger;
A sound wave control member stacked on the transducer so that ultrasonic waves transmitted and received are transmitted without loss; And
It includes; a signal processing unit for allowing the transducer to output ultrasonic waves, and electrically connected to the transducer to sense biometric information of the finger according to the received ultrasonic waves.
The transducer includes a plurality of unit piezoelectric cells arranged vertically and horizontally in a two-dimensional plane and a filling material filled between the unit piezoelectric cells adjacent to each other,
The sound wave control member includes a first signal transmission groove recessed on one side facing the transducer, a second signal transmission groove recessed on the other side opposite to the one side, and the first signal transmission groove The second signal transmission groove is connected, a connection line formed with a diameter smaller than the diameter of the first signal transmission groove and the second signal transmission groove, the first signal transmission groove, the second signal transmission groove and the Finger biometric information recognition module, characterized in that it has a control matching member that is filled in the connection line to match the acoustic impedance between the transducer and the finger. According to claim 1,
The unit piezoelectric cell,
Finger biometric information recognition module, characterized in that the base material is processed to represent the shape of a column by dry etching or micro molding. According to claim 1,
The unit piezoelectric cell includes at least one of an inorganic piezoelectric material and an organic piezoelectric material,
The inorganic piezoelectric material is formed with a plurality of pores in communication with each other,
The organic piezoelectric material is a finger biometric information recognition module, characterized in that formed in the pores or surrounding the outer circumferential surface of the inorganic piezoelectric material. A finger biometric information recognition module for recognizing biometric information including at least one of a finger vein and a fingerprint from a finger in contact,
A transducer that outputs ultrasonic waves toward the finger and receives ultrasonic waves reflected and returned from the finger;
A sound wave control member stacked on the transducer so that ultrasonic waves transmitted and received are transmitted without loss; And
It includes; a signal processing unit for allowing the transducer to output ultrasonic waves, and electrically connected to the transducer to sense bio-information of the finger according to the received ultrasonic waves.
The transducer includes a plate-shaped piezoelectric plate that outputs ultrasonic waves toward the finger,
The sound wave control member includes a first signal transmission groove recessed on one side facing the transducer, a second signal transmission groove recessed on the other side opposite to the one side, and the first signal transmission groove The second signal transmission groove is connected, a connection line formed with a diameter smaller than the diameter of the first signal transmission groove and the second signal transmission groove, the first signal transmission groove, the second signal transmission groove and the A finger biometric information recognition module having a control matching member filled in a connection line to match the acoustic impedance between the transducer and the finger. According to claim 4,
A finger biometric information recognition module further comprising; an ultrasonic transmission member inserted and stacked between the transducer and the sound wave control member so that ultrasonic waves are transmitted between the transducer and the sound wave control member. The method according to any one of claims 1 to 5,
A finger biometric information recognition module further comprising a post member for forming a vacuum space between the transducer and the signal processing unit to prevent ultrasound from being transmitted to the signal processing unit. The method according to any one of claims 1 to 5,
The signal processing unit,
An ultrasonic driving unit connected to the transducer and applying a driving signal to the transducer to output ultrasonic waves from the transducer;
An ultrasonic processing unit connected to the transducer and processing ultrasound received from the transducer;
A multiplexing logic unit that selects and outputs a specific signal that satisfies a condition from among the signals of the ultrasonic processing unit;
A signal converting unit converting a signal output from the multiplexing logic unit; And
Includes a signal processing control unit for controlling the driving signal applied from the ultrasonic driving unit to adjust the frequency of the ultrasonic wave, and controlling the operation of the ultrasonic processing unit, the multiplexing logic unit and the signal conversion unit in response to the controlled driving signal. Finger biometric information recognition module, characterized in that. The method of claim 7,
In the ultrasonic processing unit,
Finger biometric information recognition module characterized in that it further comprises the step of monitoring the received ultrasonic signal and extracting a signal for a fingerprint or finger vein from the received ultrasonic signal to correct the received ultrasonic signal. The method of claim 7,
When the signal processing control unit controls the driving signal so that the frequency of the ultrasonic wave output from the transducer indicates the first frequency, the signal processing unit detects the fingerprint and finger vein of the finger,
When the signal processing control unit controls the driving signal so that the frequency of the ultrasonic wave output from the transducer is greater than the first frequency, the signal processing unit detects the fingerprint of the finger. Finger biometric information recognition module. The method of claim 7,
The signal processing unit,
A Hilbert transform unit that converts the signal converted by the signal converter into Hilbert transform to generate a transform signal;
A shaping unit for shaping a transform signal generated through the Hilbert transform unit to generate a shaping signal;
An image replacement unit for generating a replacement signal by replacing the normalization signal generated through the shaping unit with a 3D image element;
A logic synthesizing unit that generates a 3D signal by synthesizing substitution signals generated through a plurality of the image replacement units; And
Finger biometric information recognition module comprising a; image acquisition unit for obtaining a final three-dimensional image based on the three-dimensional signal generated through the logic synthesis unit. A finger biometric information recognition module according to any one of claims 1 to 5; And
And a main control unit that controls the electronic device based on the signal output from the signal processing unit. Method for manufacturing the transducer according to claim 1,
A thick film manufacturing step of manufacturing a composite piezoelectric film using at least one of an inorganic piezoelectric material and an organic piezoelectric material included in the unit piezoelectric cell;
A thick film cutting step of cutting the composite piezoelectric film produced through the thick film manufacturing step so that a partition slit is formed in the composite piezoelectric film; And
And a slit filling step of filling the compartment slit with the filling material. The method of claim 12,
The thick film manufacturing step,
A template stacking step of stacking a template for forming pores in the base;
A precursor solution impregnating step of impregnating the temple with a precursor solution of the inorganic piezoelectric material after the temple stacking step;
A drying step of passing the precursor solution impregnation step and then drying the precursor solution of the inorganic piezoelectric material;
After the drying step, a template removal step of removing the template from the dried precursor of the inorganic piezoelectric material;
A crystallization step of crystallizing a precursor solution of the dried inorganic piezoelectric material after passing through the temple removal step;
An organic material input step of introducing the organic piezoelectric material into the precursor solution of the inorganic piezoelectric material crystallized after the crystallization step; And
And a thickening step of mixing the crystallized precursor solution of the inorganic piezoelectric material and the organic piezoelectric material to prepare the composite piezoelectric thick film. Method for manufacturing the transducer according to claim 1,
Preparing at least one of an inorganic piezoelectric material and an organic piezoelectric material included in the unit piezoelectric cell, the inorganic piezoelectric material or the organic piezoelectric material or a mixture of the inorganic piezoelectric material and the organic piezoelectric material;
Preparing a molding mold in which a cell groove corresponding to the unit piezoelectric cell is formed;
Injecting the organic piezoelectric material or the inorganic piezoelectric material or the mixed material into the molding mold to produce a green array in which the unit piezoelectric cell is formed on a base layer;
Sintering the green array to produce a sintered array;
Separating the green array or the sintered array from the molding mold; And
And filling a filler between the unit piezoelectric cells adjacent to each other in the sintered array. The method of claim 14,
Removing a base layer from the sintered array filled with the filler so that only the unit piezoelectric cell and the filler remain in the sintered array; And
And forming electrodes on both ends of the unit piezoelectric cell. A method for manufacturing a finger biometric information recognition module according to claim 4,
Preparing a base for stacking the upper electrodes;
Sequentially stacking the upper electrode, the piezoelectric plate, and the lower electrode on the base;
Etching the lower electrode to separate the lower electrode in the form of a plate corresponding to the unit cell;
Forming via holes in the piezoelectric plate and patterning connection lines for applying power to the upper electrode and the separated lower electrode to form the transducer; And
And laminating the transducer and the base on the signal processing unit so that the signal processing unit and the connection line are electrically connected.

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