Shear force sensor element array

Abstract

To solve the problem that a pressure sensor for evaluating mechanical properties of a single cell requires resolution of about 10-plus μm in the biological and life science fields, and none of existing pressure sensors can detect pressure in a microscopic region, resulting in the use of a high-precision device such as an atomic force microscope.SOLUTION: A pressure sensor element array for detecting shear force in a microscopic region is provided by forming a piezoelectric resin membrane on a surface of an ion image sensor formed on a Si substrate, and providing multiple elastic bodies for receiving external force for converting a lateral force (shear force) into a vertical force.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a sensor element array that detects minute shear force and normal force with minute spatial resolution at the cellular level, and further detects the pH of a sample simultaneously. [Background technology]

[0002] CMOS type ion image sensors (Non-Patent Document 1) can detect changes in the potential of the sensor surface that accompany changes in pH or hydrogen ion concentration, and in extended gate CMOS types, a Ta2O5 sensitive film is formed on the top surface. If a piezoelectric resin film is further provided on the sensitive film, physical forces can be detected. The direction of the detected force is perpendicular to the sensor surface (Non-Patent Document 2).

[0003] Meanwhile, in the field of biology and life science, the mechanical properties of cells are attracting attention. Mechanical properties are the deformability or resistance to deformation of cells when subjected to mechanical force, and their evaluation is the characterization of cell deformation in response to mechanical force over time. One example of an application is the specific diagnosis of cancer cells based on their deformability (hardness). In drug screening, safety can be confirmed by evaluating the period of muscle contraction due to the pulsation of cardiomyocytes caused by drug administration. In these cases, it is desirable to also detect forces horizontal to the sensor surface (sometimes referred to as shear forces in this specification). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 5-26744 [Patent Document 2] JP 2014-115282 A [Non-patent literature]

[0005] [Non-Patent Document 1] You-Na Lee, and et al., "High-density 2-um-picth pH image sensor with high-speed operation up to 1933 fps," IEEE Trans. on Biomedical Circuits aand Systems, vol.13, issue2, pp. 352-363, (2019). [Non-Patent Document 2] You-Na Lee, and et al., "Super spatial resolution pressure image sensor based on bonding technique of PVDF film on two micrometer pitch COMS potentiometric sensor array," The 20th International Conference on Solid-State Sensors, Actuators and Microsystems, W3P.111, pp. 2158-2161, (2019). Summary of the Invention [Problem to be solved by the invention]

[0006] Patent Document 1 shows a sensor that can detect forces in three axial directions. The peripheral part of a flexible disk-shaped substrate is fixed to a sensor housing, and an acting body is bonded to the center part. An XYZ-3D coordinate system is defined for an origin O in the substrate, and four pairs of detectors are arranged along the X axis, and each detector has a sandwich structure in which a piezoelectric element is sandwiched between an upper electrode and a lower electrode. When a force Fx in the X axis direction acts on the acting body due to the action of acceleration, the disk-shaped substrate bends, and a positive or negative charge is generated in each electrode. The mode of charge generation depends on the direction of the applied force, and the amount of charge generation depends on the magnitude of the applied force. Based on this charge generation pattern, each axial component of the applied force can be detected.

[0007] Supporting the flexible substrate is an issue in realizing a sensor structure that detects shear force in a microscopic area using the configuration shown in Patent Document 1. In order to achieve spatial resolution at the micron level, there is no other way than to use a semiconductor planar process, and a structure in which a piezoelectric element is sandwiched between electrodes from above and below makes the manufacturing process complicated.

[0008] Patent Document 2 discloses a tactile sensor including a first substrate having a plurality of first electrodes, a second substrate having a plurality of second electrodes corresponding to the plurality of first electrodes, and a dielectric inserted between the first substrate and the second substrate, characterized in that the second electrode corresponding to any one of the plurality of first electrodes is arranged in one direction away from the corresponding electrode, and the second electrode corresponding to another first electrode adjacent to any one of the plurality of first electrodes is arranged in the other direction away from the corresponding electrode. The sensor is configured to detect normal force and shear force from changes in capacitance between the electrodes.

[0009] Even in the structure shown in Patent Document 2, assuming that a semiconductor planar process is used, a support means for the dielectric layer inserted between the first and second substrates is an issue. Giving the front and back surfaces the same functions is difficult in a semiconductor planar process.

[0010] In Patent Documents 1 and 2, a stress detection element is formed using a flexible material or a dielectric material as a substrate. It is difficult to improve the spatial resolution in detecting mechanical force without using a semiconductor planar process suitable for microfabrication.

[0011] Pressure sensors for evaluating the mechanical properties of a small area, such as a single cell, require a resolution of about 10-odd μm. Current pressure sensors are not capable of detecting pressure in a small area, and high-precision equipment such as atomic force microscopes (AFMs) are used. AFMs can detect a wide range of forces, from about 10 pN to 10 μN, but there are issues with measurement throughput. [Means for solving the problem]

[0012] Taking the above circumstances into consideration, the inventors of the present application have realized a sensor element array that detects shear force in a microscopic area by forming a piezoelectric resin film on the surface of a CMOS-type ion image sensor formed on a Si substrate, and further providing multiple elastic bodies to receive an external force that converts a lateral force (shear force) into a vertical force.

[0013] When a shear force is applied to the side of the elastic body shown in Figure 1, shear deformation occurs. If the side shape of the elastic body is rectangular, it will deform into a parallelogram. When a shear force is applied to the left side of the elastic body, a tensile stress acts along the diagonal line ascending to the right, and a compressive stress acts along the diagonal line descending to the left.

[0014] As described above, if the bottom surface of the elastic body is in contact with another layer in a state where shear deformation occurs, the layer will be subjected to tensile stress at the start point of the shear force application and compressive stress at the end point due to the elasticity of the elastic body. If the lower layer has a structure including a piezoelectric resin film, the piezoelectric resin film will be subjected to tensile stress at the part located at the start point of the elastic body and compressive stress at the part located at the end point. The shear force applied to the elastic body can be identified by detecting the change in potential at each part of the piezoelectric resin film.

[0015] Here, we consider the shape of the elastic body. Because a semiconductor planar process is used, the height of the elastic body is about a few μm, with 1 μm to 10 μm being appropriate, but a higher height is preferable. The shape of the elastic body viewed from the top or bottom is preferably in the range of 1 μm x 1 μm to 10 μm x 10 μm, but since the degree of shear deformation is large, it is more convenient for the shape of the elastic body to be small.

[0016] The amount of charge Qp generated when a force F is applied perpendicular to the piezoelectric film is the piezoelectric constant d 33 It is expressed by the following formula using Qp=d 33 ×F (1) Next, the capacitance of the sensitive membrane per unit of the potential detection unit C SENS Therefore, the theoretical sensitivity of the output voltage Vout to a vertical force is given by the following equation: Vout=Qp / C SENS (2) Sensitive membrane capacitance C SENS If the piezoelectric constant is 0.71 fF and the piezoelectric constant is 18 pC / N, which is the standard value for polyvinylidene fluoride material, the theoretical sensitivity of the output voltage is 25.3 mV / μN. The noise level of the potential detection unit in Non-Patent Document 1 is about 3 mV, so it can detect a force of about 0.1 μN.

[0017] When a force is applied to an elastic body in the horizontal direction, the force in the vertical direction is determined by the Poisson's ratio. If the elastic body is epoxy resin, the Poisson's ratio is around 0.3, which means that about 1 / 3 of the horizontal force is applied, and the horizontal shear force can be detected as a vertical force.

[0018] A first aspect of the present invention is a shear force sensor element array having a sensing section on a Si substrate that changes the depth of a potential well depending on a surface potential, and a potential detection unit in which an interlayer insulating film is formed on the sensing section, a metal electrode is formed on the interlayer insulating film, and the metal electrode is electrically connected to the sensing section via a metal through hole provided in the interlayer insulating film, the potential detection units are arranged in an array, and a first sensitive film made of a sensitive film (Ta2O5, Si3N4, or other thin film that adsorbs hydrogen ions) is formed directly on the first metal electrode of the sensing unit constituting the array, a second sensitive film made of a resin thin film having piezoelectricity is formed directly on the first sensitive film, a metal film (waterproof film) is formed directly on the second sensitive film, a plurality of elastic bodies for receiving external forces are formed on the metal film, and at least two or more potential detection units are arranged directly below the elastic bodies.

[0019] A second aspect of the present invention is characterized in that, in the first aspect, the elastic bodies are arranged at a distance from each other, the second sensitive film and the metal film located in the gap between the elastic bodies are removed, and the first sensitive film is exposed.

[0020] A third aspect of the present invention is characterized in that, in the first or second aspect, there are at least four elastic bodies, at least two of the elastic bodies are arranged on a first straight line, and at least two of the elastic bodies are arranged on a second straight line perpendicular to the first straight line. Effect of the Invention

[0021] This invention enables imaging of shear force with a spatial resolution of the μm level, and enables direct observation of cell stiffness, pulsation of cardiomyocytes, etc., which are of interest in the fields of biology and life science. Furthermore, since the pH image sensor is used as a potential detector array, chemical properties such as pH can be detected simultaneously with mechanical properties of cells in culture medium. [Brief description of the drawings]

[0022] [Figure 1] FIG. 2 is a schematic cross-sectional view of the shear force sensor element array shown in the first embodiment. [Diagram 2] FIG. 6 is a schematic cross-sectional view of a shear force sensor element array shown in a second embodiment. [Diagram 3] FIG. 13 is a schematic perspective view showing an example of the arrangement of shear force detection sections of the shear force sensor element array shown in the third embodiment. [Figure 4] 2 is a cross-sectional view showing a configuration of a potential detection unit according to the present embodiment. FIG. [Diagram 5] 5A to 5C are potential distribution diagrams illustrating the operation of the potential detection unit according to the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] In the shear force sensor element array of the present invention, the potential detection unit and the piezoelectric resin film are fabricated separately and then bonded together to form the elastic body. This is to perform a polarization process on the piezoelectric resin film. At least two potential detectors are required below each elastic body to detect the potential at each of the opposite sides of the bottom surface of the elastic body. Since the dimensions of the elastic body to which the shear force is applied are set to about several μm, the element spacing of the potential detector is preferably about 1 to 2 μm.

[0024] (First embodiment) A schematic cross-sectional view of a shear force sensor element array 100 according to this embodiment is shown in FIG. 1. Note that in the schematic cross-sectional view of FIG. 1, parts not necessary for the description of the first embodiment are omitted. The shear force sensor element array 100 is composed of a potential detector array 60 consisting of a plurality of CMOS extended gate type potential detection units 1, and a shear force detection section 40. The potential detection unit 1 has interlayer insulating films 30, 33, a metal electrode 35 directly on the interlayer insulating films 30, 33, and a hydrogen ion sensitive film 36 is formed in a shape that covers the metal electrode 35. The metal electrode 35 is electrically connected to the sensing area defining electrode 13 of the potential detection unit 1 via the metal through holes 31, 34 in the interlayer insulating films 30, 33 and the metal connection section 32.

[0025] Next, the shear force detection unit 40 will be described. The shear force detection unit 40 is formed on the potential detector array 60, and is composed of a piezoelectric resin film 42, a metal thin film 41, and an elastic body 43. The piezoelectric resin film 42 uses a polyvinylidene fluoride (PVDF) resin film. PVDF is a highly resistant, high-purity thermoplastic fluoropolymer. PVDF is a ferroelectric polymer that exhibits piezoelectricity and pyroelectricity, and is therefore used in pressure sensors. Alternatively, a resin made of a copolymer of vinylidene fluoride and trifluoroethylene (VDF-TrFE) or a copolymer of vinylidene fluoride and tetrafluoroethylene (VDF-TeFE) may be used.

[0026] Since the mechanical properties of the cells are evaluated in an aqueous solution such as a culture solution, it is desirable to form a thin metal film 41 for waterproofing purposes on the piezoelectric resin film 42. In this embodiment, an Au film is formed by sputtering.

[0027] Since the elastic body 43 needs to be selectively formed in a minute area, it is preferable to use a material that can be formed using a semiconductor planar process. In this embodiment, a thick-film resist SU-8 is used. SU-8 is a negative photoresist based on EPON SU-8, an epoxy resin, and can be applied by spin coating. It has high viscosity, and an elastic body 43 with a high aspect ratio can be formed. SU-8 is biocompatible and is suitable for cell evaluation.

[0028] The dimensional specifications of the shear force detection section 40 were set as follows: thickness of the piezoelectric resin film 1 μm, thickness of the Au thin film 200 nm, height of the elastic body 43 5 μm, and area of ​​the elastic body pattern 8 μm×8 μm.

[0029] In the polarization process, an indium tin oxide (ITO) electrode and a PVDF film are laminated on a polyethylene terephthalate (PET) film substrate, and a polarization process is performed by applying a high voltage of about 10 kV. After the polarization process, the ITO electrode is dissolved to peel off the PVDF film from the PET film.

[0030] In the transfer process, the peeled PVDF film is attached onto the potential detector array 60. The transfer process is conveniently performed in a liquid such as pure water, and it is desirable to subject the surfaces of the potential detector array 60 and the PVDF film to a hydrophilic treatment using O2 plasma in advance.

[0031] After the transfer process and the Au film formation process, the elastic body 43 formation process is carried out. A thick-film photoresist SU-8 is applied by spin coating at a rotation speed of 3000 rpm. As pre-treatment before application, it is desirable to perform a heat treatment at about 100°C and a hydrophobic surface treatment (e.g., HMDS treatment). After application, a pre-bake is performed at 95°C for 2 minutes. The SU-8 is processed by photolithography to form the elastic body 43. Lithography is performed by exposure to i-line, and after exposure, a heat treatment is performed at 95°C for 1 minute. Thereafter, the uncrosslinked parts that were not irradiated with i-line are dissolved in a developer dedicated to SU-8, and rinsed with isopropyl alcohol.

[0032] In the shear force sensor element array 1 produced by the above process, a tensile stress is applied to the piezoelectric resin film 42 on the starting point side of the shear force applied to the elastic body 43, and a compressive stress is applied to the piezoelectric resin film 42 on the end point side of the shear force. The piezoelectric resin films 42 generate electric potentials according to the forces they receive, and the generated electric potential changes are transmitted via the hydrogen ion sensitive film 36 of the electric potential detection unit 1 to the sensing regions 6 of the electric potential detection unit 1 located directly below the starting point side and the end point side, respectively. In the case of a PVDF film, since the piezoelectric coefficient is positive, the detected electric potential changes in the negative direction on the starting point side and in the positive direction on the end point side.

[0033] Regarding the above detection results, if the potential changes on the starting point side and the ending point side are in the same direction, it can be determined that a normal force is mainly being applied. If the potential changes on the starting point side and the ending point side are in the same direction and the detected potential change amounts are different, this is a case where an axial deviation from the vertical direction has occurred. In this case, if the potential detection units 1 are placed diagonally at the four corners of the bottom surface of the elastic body 43, the axial deviation angle from the vertical direction can be identified.

[0034] Second embodiment FIG. 2 shows a schematic cross-sectional view of the shear force sensor element array 100 according to this embodiment. In the schematic cross-sectional view of FIG. 2, parts unnecessary for the description of the second embodiment are omitted. The second embodiment is provided with a pH detection unit 50 by modifying the first embodiment. By removing the metal film and the piezoelectric thin film 42 in the part where the elastic body 43 is not formed in the first embodiment, the hydrogen ion sensitive film 36 that identifies pH is exposed. As a process for removing the metal film 41, it is preferable to use an iodine-based etching solution such as a mixture of I2+KI, which allows selective etching by lithography, in removing the Au film. Alternatively, patterning is possible using a lift-off method using a photoresist, and the area to be waterproofed by the metal film may be determined in advance.

[0035] Next, as the removal process of the PVDF membrane, the PVDF membrane can be processed using a dimethylacetamide (DMA) solution as an etching solution in the wet process, and can be processed by reactive ion etching with O2 plasma in the dry process. The second embodiment thus fabricated enables simultaneous detection of shear force and pH.

[0036] The shear force sensor element array 100 fabricated by the above steps can detect shear force in the same manner as in the first embodiment. In addition, the array is provided with a pH detection section 50 and can detect pH.

[0037] It is known that cancer cells have different deformability and pH in the vicinity of the cancer cells compared to normal cells. By using the shear force sensor element array according to the second embodiment, the deformability of the cancer cells is identified by the shear force sensor unit, and the pH change in the vicinity of the cancer cells is also identified, thereby improving the accuracy of cancer cell diagnosis.

[0038] (Third embodiment) The shear force sensor element array 100 according to this embodiment can evaluate the muscle contraction of cardiomyocytes and the movement of prokaryotic cells. Here, the potential detector array according to Non-Patent Document 1 has a frame rate of about 2000 fps and a time resolution of about 0.5 mSec. If a plurality of shear force detection units 40 are arranged on a line and the arrangement interval of the shear force detection units 40 is 0.1 mm, a movement speed of up to 0.2 m / Sec (20 cm per second) can be detected. This is a sufficient speed for evaluating cell movement. In this embodiment, at least two or more shear force detection units 40 are arranged on each of two orthogonal lines on the xy axis, so that the movement direction and movement speed on the xy plane can be detected. Note that even if the first and second lines do not satisfy the orthogonal relationship, the movement direction and movement speed can be detected, but the detection accuracy will be reduced.

[0039] (Configuration and operation of the potential detection unit) 5 shows the fundamental configuration of the CMOS extended gate type potential detection unit 1 constituting the shear force sensor element array 100 of this embodiment. In the potential detection unit 1, a sensing (Sen) region 6, a first floating diffusion (FD1) region 7, a charge transfer (TG) region 10, a second floating diffusion (FD2) region 8, a charge transfer control (AG) region 11, a charge accumulation (FD) region 9, a reset (RG) region 12, and a second charge discharge (D2) region 5 are defined on a silicon substrate 2 in that order in the direction in which charges are transferred from a first charge discharge (D1) region 4.

[0040] The division of each region is defined by the difference in the conductivity type of the silicon semiconductor on the surface of the silicon substrate 2. When electrons are used as charge, the first charge drain (D1) region 4, the first floating diffusion (FD1) region 7, the second floating diffusion (FD2) region 8, the charge accumulation (FD) region 9 and the second charge drain (D2) region 5 are n+ type regions, and the sensing (Sen) region 6, the charge transfer (TG) region 10, the charge transfer control (AG) region 11 and the reset (RG) region 12 are p-type regions.

[0041] A silicon oxide insulating film 3 is laminated on the surface of the silicon substrate 2. A sensing region defining electrode 13 is formed on the sensing (Sen) region 6. Furthermore, a silicon oxide layer 33 and a metal electrode 35 are laminated, and a tantalum pentoxide film is laminated on the surface of the metal electrode 35 as a first sensitive film 37. A potential change on the surface of the first sensitive film 37 is transmitted to the sensing region defining electrode 13 via metal through-holes 31, 34 and a metal connection part 32 buried in the silicon oxide layers 30, 33. A charge transfer electrode 14 is formed on the charge transfer (TG) region 10 via the silicon oxide insulating film 3, a charge transfer control electrode 15 is formed on the charge transfer control (AG) region 11 via the silicon oxide insulating film 3, and a reset electrode 16 is formed on the reset (RG) region 12 via the silicon oxide insulating film 3.

[0042] The first floating diffusion (FD1) region 7 is disposed adjacent to the sensing (Sen) region 6, and accumulates an amount of charge reflecting the potential of the sensing (Sen) region 6. A sufficiently low voltage or a sufficiently high voltage, for example, a ground potential (GND) or a power supply voltage (VDD), is appropriately applied to the potential of the charge transfer (TG) region 10, and the charge transfer (TG) region 10 transfers charges between the first floating diffusion (FD1) region 7 and the second floating diffusion (FD2) region 8.

[0043] The charge transfer control (AG) region 11 is disposed close to and between the second floating diffusion (FD2) region 8 and the charge accumulation (FD) region 9, and is applied with a ground potential or a predetermined potential between the power supply voltage and the potential of the sensing (Sen) region 6. The charge transfer control (AG) region 11 controls the amount of charge transferred from the second floating diffusion (FD2) region 8 to the charge accumulation (FD) region 9.

[0044] The reset (RG) region 12 is disposed close to and between the charge accumulation (FD) region 9 and the second charge drain (D2) region 5, and a ground potential or a power supply voltage is applied to the reset (RG) region 12. The reset (RG) region 12 controls charge transfer from the charge accumulation (FD) region 9 to the second charge drain (D2) region 5.

[0045] The operation of the potential detection unit 1 will be described with reference to Figure 5. The operation of the potential detection unit 1 consists of four steps, from Figure 5A to Figure 5D. The height of the potential is indicated by an arrow, with the lower side being a higher potential. Here, it is assumed that the charge is an electron. In the following explanation, electrons, which are negatively charged, are used as the charge.

[0046] A sufficiently high voltage, for example, a power supply voltage, is applied to the first charge drain (D1) region 4 and the second charge drain (D2) region 5 throughout all steps, and the first charge drain (D1) region 4 and the second charge drain (D2) region 5 always drain charge.

[0047] 5A shows the initial state. If the potential of the reset (RG) region 12 is the power supply voltage, the potentials of the second charge drain (D2) region 5 and the charge accumulation (FD) region 9 become equal, and the charge in the charge accumulation (FD) region 9 is drained. Note that an indefinite amount of charge remains in the first floating diffusion (FD1) region 7 and the second floating diffusion (FD2) region 8. At the end of this step, the potential of the reset (RG) region 12 must be set to the ground potential, and charge transfer between the charge accumulation (FD) region 9 and the second charge drain (D2) region 5 must be blocked.

[0048] In Fig. 5B, charge is injected into the second floating diffusion (FD2) region 8. The potentials of the charge transfer (TG) region 10 and the charge transfer control (AG) region 11 are temporarily set to ground potential, and charge is injected from the charge injection circuit 20. The minimum potential of the charge held in the second floating diffusion (FD2) region 8 is equal to the ground potential. When this step is completed, charge injection from the charge injection circuit 20 is terminated.

[0049] 5C, the potential of the charge transfer (TG) region 10 is set to the power supply voltage, and a part of the charge in the second floating diffusion (FD2) region 8 is transferred to the first charge drain (D1) region 4 via the first floating diffusion (FD1) region 7. The minimum potential of the charge remaining in the second floating diffusion (FD2) region 8 is determined by the potential of the sensing (Sen) region 6.

[0050] 5D, the potential of the charge transfer (TG) region 10 is set to the ground potential, and the movement of charges between the first floating diffusion (FD1) region 7 and the second floating diffusion (FD2) region 8 is blocked. In this step, the minimum potential of the charges held in the first floating diffusion (FD1) region 7 is held at the potential detected by the sensing (Sen) region 6, and the minimum potential of the charges held in the second floating diffusion (FD2) region 8 is held at the potential of the charge transfer control (AG) region 11. At this time, by making the potential of the charge transfer control (AG) region 11 higher than the potential of the sensing (Sen) region 6, an amount of charge according to the potential difference is transferred to the charge accumulation (FD) region 9.

[0051] Since the amount of charge stored in the charge storage (FD) region 9 reflects the level of the potential of the sensing (Sen) region 6, the potential can be measured by a buffer circuit 21 having a high input impedance or the like.

[0052] The present invention is not limited to the above-mentioned embodiment and examples. Various modifications that do not depart from the spirit of the claims and that can be easily conceived by a person skilled in the art are also included in the present invention. [Explanation of symbols]

[0053] 1, 1A~1F Potential detection unit 2. Silicon substrate 3. Insulating film (silicon oxide film) 4. First charge drain (D1) region 5 Second charge drain (D2) region 6 Sensing area 7 First floating diffusion (FD1) region 8 Second floating diffusion (FD2) region 9 Charge accumulation (FD) region 10 Charge Transfer (TG) Region 11 Charge transfer control (AG) area 12 Reset (RG) area 13 Sensing area defining electrode 14 Charge transfer electrode 15 Charge transfer control electrode 16 Reset electrode 20 Charge injection circuit 21 Output voltage detection circuit (buffer circuit) 30, 33 Interlayer insulating film (silicon oxide film) 31, 34 Metal through hole 32 Metallic joint 35 Metal electrode 36 Hydrogen ion sensitive membrane 40, 40A, 40B Shear force detector 41 Metal membrane (for waterproofing) 42 Piezoelectric resin film 43 Elastic Body 50 pH detector 60 Potential Detector Array 100 Shear force sensor element array 101 pH and shear force sensor element array

Claims

1. a sensing section on a Si substrate that changes the depth of a potential well depending on the surface potential; an interlayer insulating film formed on the sensing section; a metal electrode formed on the interlayer insulating film; the metal electrode electrically connected to the sensing section via a metal through-hole provided in the interlayer insulating film; and a potential detection unit, the potential detection units being arrayed; A sensitive film (Ta) is placed directly above the metal electrodes of the potential detection units that form an array. 2 O 5 , Si 3 N 4 a first sensitive film made of a thin film that adsorbs hydrogen ions (a thin film that adsorbs hydrogen ions, etc.), and a second sensitive film made of a resin film having piezoelectricity is formed directly on the first sensitive film; A shear force sensor element array characterized in that a metal film (waterproof film) is formed directly above the second sensitive film, multiple elastic bodies for receiving external forces are formed as rectangular parallelepipeds on the metal film, and at least two or more potential detection units are arranged directly below the elastic bodies.

2. The shear force sensor element array according to claim 1, characterized in that the elastic body has a square shape of 1 μm x 1 μm to 10 μm x 10 μm when viewed from the top or bottom, and a height of 1 μm to 10 μm.

3. 3. The shear force sensor element array according to claim 1, wherein at least four of the elastic bodies are arranged on the surface of the shear force sensor element array, at least two of the elastic bodies are arranged on a first straight line on the surface of the shear force sensor element array, and at least two of the elastic bodies are arranged on a second straight line perpendicular to the first straight line.

4. A shear force sensor element array as described in claim 3, characterized in that the elastic bodies are arranged at a distance from each other, and the second sensitive film and the metal film located in the voids of the elastic bodies are removed to expose the first sensitive film, thereby making it possible to detect pH.

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