JP2016050877A - Sensor device and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect such a large pressure that can be touched by a person and other desired detection objects without hardly causing breakage, and eliminate the need for voltage application for sensing.SOLUTION: A pressure sensor 10 has a cantilever portion 12 formed on a silicon substrate 11. The pressure sensor 10 has a lower electrode 13, a piezoelectric thin film 14 and an upper electrode 15 laminated on the upper surface of the cantilever portion 12. The lower electrode 13 and the upper electrode 15 are connected to electrode pads 17a and 17b through bonding wires 16a and 16b. The electrode pads 17a and 17b are formed on the upper surface of a circuit board 18 together with a silicon substrate 11. The circuit board 18 mounts a detection circuit portion for generating a pressure detection signal based on a signal sent from the electrode pads 17a and 17b, and the like. The above whole configuration of the pressure sensor 10 is sealed by a flexible non-conductive resin 19. A pressure of an object to be detected is applied through the flexible non-conductive resin 19.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a sensor device and a manufacturing method thereof, and more particularly to a sensor device such as a pressure sensor using a piezoelectric thin film and a manufacturing method thereof.

  As a pressure sensor that measures pressure, in consideration of miniaturization and energy saving, MEMS (Micro Electro Mechanical Systems) technology is applied, and the thin film actuator part (sensor part) has a cantilever structure (cantilever structure). A pressure sensor is desirable. When considering miniaturization, MEMS is the only technology that can produce a pressure sensor with a chip size of several mm square, and it is difficult to miniaturize the sensor itself with other printed circuit board technologies.

  In the pressure sensor to which the MEMS technology is applied, for example, a piezoresistive film is formed on a silicon substrate, and the planar shape of the piezoresistive film forming portion is substantially rectangular, and one end in the longitudinal direction thereof is connected and fixed to the substrate. In addition, there are many cantilever structures (cantilever structures) in which the other end is a free end. In this pressure sensor, the detected pressure acts on the cantilever and the bend amount (piezoresistance value) of the cantilever changes according to the pressure, and a pressure measurement signal corresponding to the bend amount is output. There is an advantage that can be detected.

  However, while the pressure sensor of the above cantilever structure is highly sensitive, the tip of the cantilever has a free end and low rigidity, so that it has been used only for detecting relatively small pressures such as air pressure and water pressure.

  On the other hand, in order to increase the rigidity of the pressure sensor and enable detection of stronger pressure, a doubly-supported beam structure in which both ends of a strip-like action part with electrode layers formed on both upper and lower sides are fixed to a frame part having an opening As a pressure sensor, a pressure sensor has been proposed that generates an electrical signal between upper and lower electrode layers when an external force is applied to the belt-like moving part (see, for example, Patent Document 1).

  In addition, the thin film layer having a displacement film that expands and contracts in the direction along the film surface by the drive signal, and both ends or the periphery of the thin film layer are fixed, and the thin film layer is perpendicular to the film surface by the extension of the displacement film by the drive signal. There has also been proposed an actuator provided with a substrate that is displaced in a straight line (for example, see Patent Document 2). According to this actuator, the thin film layer has an initial compressive stress along the film surface when not driven, and the initial compressive stress is smaller than the initial compressive stress that maximizes the amount of displacement of the thin film layer when driven. By doing so, a larger displacement amount can be obtained, and it can also be used as a pressure sensor.

JP-A-8-114408 JP 2011-140117 A

  However, even the pressure sensor having the structure described in Patent Documents 1 and 2 does not have a sufficient amount of pressure that can be detected. For example, it can be destroyed by a force (1 to 10 N) that can be touched by humans. There is a fear. For example, in a pressure sensor having a cantilever structure, there is a possibility that the connecting portion (root portion) of the fixed end of the cantilever is broken. Further, in a pressure sensor using a piezoresistive film, a voltage must be continuously applied for sensing, which is a problem from the viewpoint of energy saving.

  The present invention has been made in view of the above points, and can detect a pressure that is large enough to be touched by humans and other desired detection objects with little risk of destruction, and eliminates the need for voltage application for sensing. And it aims at providing the manufacturing method.

  In order to achieve the above object, a sensor device of the present invention mechanically deforms in response to an input of a detection target and generates an electrical signal corresponding to the amount of deformation, and supports the detection unit. Flexibility to seal the entire element including the support unit, the detection circuit unit that generates a detection signal according to the signal amount of the electrical signal from the detection unit, and the detection unit, the support unit, and the detection circuit unit A non-conductive resin, and detecting an input of the detection target input through the flexible non-conductive resin.

  Here, in the detection unit, a piezoelectric thin film is formed on an elongated flat rectangular substrate in which one of both ends in the longitudinal direction is fixed by the support unit and the other is a free end capable of vibration. A cantilever part that generates an electrical signal by detecting the amount of bending of the substrate that is bent by an input from a detection target by the piezoelectric thin film, or both ends in the longitudinal direction are fixed by the support part. A piezoelectric thin film is formed on a flat rectangular parallelepiped substrate, and a bridge portion that generates an electrical signal by detecting the amount of bending of the substrate that is bent by an input from the detection target, or the detection target It is a diaphragm part which detects the bending of the thin part bent by the input from the piezoelectric thin film and generates an electric signal.

  In order to achieve the above object, the sensor device of the present invention has a piezoelectric device formed on a long and flat rectangular parallelepiped substrate in which one of both ends in the longitudinal direction is a fixed end and the other is a free end. A thin film is formed, and a bending amount of the free end changes according to an applied pressure, and an output charge according to the bending amount is generated by the piezoelectric thin film, and the fixed end of the cantilever part An entire element comprising a support part for fixing the sensor, a detection circuit part for generating a pressure detection signal corresponding to an applied pressure from the output charge generated by the piezoelectric thin film, and the cantilever part, the support part and the detection circuit part And a flexible non-conductive resin for sealing the pressure, and detecting the input of the pressure input through the flexible non-conductive resin.

  Here, the support portion is constituted by the silicon substrate of an SOI substrate in which a silicon substrate, a silicon oxide film, and a silicon structure are stacked in this order, and the substrate of the cantilever portion is the silicon oxide film of the SOI substrate. And a laminated body of the silicon structures.

  The flexible non-conductive resin is characterized in that the hardness thereof is set so hard that the linear detection range of the detection target is widened.

  In order to achieve the above object, the method of manufacturing the sensor device according to the present invention has an elongated flat rectangular parallelepiped shape in which one of both end portions in the longitudinal direction is fixed by a support portion and the other is a free end. A forming step of forming a cantilever portion having a piezoelectric thin film formed on a substrate; a fixing step of fixing a bottom surface of the support portion of the cantilever portion on a circuit substrate of a detection circuit portion; and a step of fixing the piezoelectric thin film of the cantilever portion. A wiring process for wiring between the first electrode pad of the driving electrode and the second electrode pad on the circuit board, and the entire element composed of the cantilever part and the circuit board that have undergone the wiring process are not flexible. And a sealing step of sealing with a conductive resin.

  According to the present invention, it is possible to detect a pressure that is large enough to be touched by a human being or other desired detection target with almost no risk of destruction. Further, according to the present invention, voltage application for sensing can be made unnecessary, and energy saving can be realized.

It is a perspective view of one embodiment of a sensor device concerning the present invention. It is sectional drawing explaining the outline | summary of operation | movement of one Embodiment of the sensor apparatus which concerns on this invention. It is a circuit diagram of an example of the detection circuit unit in the sensor device according to the present invention. It is an applied force versus output charge characteristic diagram of an example of an embodiment of a sensor device according to the present invention. 1 is an external view of an example of a sensor device according to the present invention. It is element sectional drawing of the 1st process of one Embodiment of the manufacturing method of the sensor apparatus which concerns on this invention. It is element sectional drawing and a top view of the 2nd process of one Embodiment of the manufacturing method of the sensor apparatus concerning the present invention. It is element sectional drawing and the top view of the 3rd process of one Embodiment of the manufacturing method of the sensor apparatus which concerns on this invention. It is element sectional drawing and the top view of the 4th process of one Embodiment of the manufacturing method of the sensor apparatus which concerns on this invention. It is element sectional drawing of the 5th process of one Embodiment of the manufacturing method of the sensor apparatus which concerns on this invention. It is element sectional drawing of the 6th process of one Embodiment of the manufacturing method of the sensor apparatus which concerns on this invention. It is sectional drawing when using one Embodiment of the sensor apparatus which concerns on this invention as a vibration sensor and an electric power generation element. It is a perspective view which shows the other example of the pressure detection part of the sensor apparatus which concerns on this invention.

Next, embodiments of the sensor device and the manufacturing method thereof according to the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a perspective view of an embodiment of a sensor device according to the present invention. As shown in the figure, a pressure sensor 10 which is a sensor device of the present embodiment is a laminate of a silicon oxide film and a silicon structure thinner than a silicon substrate 11 on a rectangular parallelepiped silicon substrate 11. A cantilever portion 12 is formed. The cantilever portion 12 has a board structure with a T-shaped plane, which includes a first cantilever portion 12a and a second cantilever portion 12b each having an elongated flat plate shape (flat rectangular parallelepiped shape) whose longitudinal directions are orthogonal to each other. . Note that the cantilever portion 12 may be configured only by the second cantilever portion 12b.

  All of the first cantilever portions 12 a are integrally formed on the upper surface of the silicon substrate 11. The second cantilever portion 12b is a cantilever in which one end is connected to the longitudinal center of the first cantilever portion 12a and the other end is a free end that can vibrate in the vertical direction. It is a beam structure. Here, as an example, the second cantilever portion 12b has a length in a direction orthogonal to the longitudinal direction of the first cantilever portion 12a, for example, about 50 μm to 10 mm, a width, for example, about 300 μm, and a thickness, for example, 100 nm to 100 μm. Degree.

  In the pressure sensor 10, a lower electrode 13, a piezoelectric thin film 14 such as lead zirconate titanate (PZT) as an example of a pressure sensitive element, and an upper electrode 15 are laminated in this order on the upper surface of the cantilever portion 12. The lower electrode 13 is connected to the electrode pad 17a via the bonding wire 16a, and the upper electrode 15 is connected to the electrode pad 17b via the bonding wire 16b. The electrode pads 17 a and 17 b are formed on the upper surface of the circuit board 18 together with the silicon substrate 11. The circuit board 18 is mounted with a detection circuit unit that generates a pressure detection signal based on signals from the electrode pads 17a and 17b. The pressure sensor 10 is characterized in that the entire configuration described above is sealed (in other words, embedded) with the flexible non-conductive resin 19. The height of the flexible non-conductive resin 19 is, for example, about 1.2 mm. As the flexible non-conductive resin 19, for example, silicon rubber, polydimethylsiloxane (PDMS) or the like can be used.

  The pressure sensor 10 having the above configuration can be manufactured as follows. For example, a large number of sensor body portions (portions excluding bonding wires 16a and 16b, electrode pads 17a and 17b, circuit board 18 and flexible non-conductive resin 19) are collectively formed by a MEMS process. Separate into sensor body. After that, a normal ceramic package is fixed to a circuit board 18 such as a screen rigid board by die bonding for each separated sensor main body, and after wiring with bonding wires 16a and 16b, the entire structure is flexible and non-conductive. Sealing with a conductive resin 19.

  Next, an outline of the operation of the pressure sensor 10 of the present embodiment will be described with reference to FIG. FIG. 2 is a cross-sectional view for explaining the outline of the operation of the pressure sensor 10. In the figure, the same components as those in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted. However, in FIG. 2, the lower electrode 13, the upper electrode 15, the bonding wires 16a and 16b, and the electrode pads 17a and 17b in FIG. 1 are omitted.

  As shown in FIG. 2A, a rectangular parallelepiped block 21 made of hard plastic or the like is placed on the upper surface of the flexible non-conductive resin 19. At this time, the second cantilever portion 12b maintains the initial horizontal state. Subsequently, as shown in FIG. 2B, when a force is applied to the block 21 in the direction of the arrow 22 (that is, downward), the upper portion of the flexible non-conductive resin 19 is deformed, Accordingly, the tip which is the free end of the second cantilever portion 12b bends downward as indicated by 24. Then, as schematically indicated by 25, the piezoelectric thin film 14 generates an output charge having a value corresponding to the magnitude of this bending. The generated output charge is detected by a detection circuit unit mounted on the circuit board 18 and further taken out as a pressure detection signal having a voltage divided by the capacity of the measurement system. In the cantilever portion 12 having the piezoelectric thin film 14 formed on the upper surface, the second cantilever portion 12b is mechanically deformed according to the pressing of the force to be detected as described above, and the deformation amount (bending amount) is increased. A detection unit that generates a corresponding electrical signal (here, output charge) is configured.

  The block 21 used to press the flexible non-conductive resin 19 is an example, and the flexible non-conductive resin 19 may be pressed directly without providing the block 21. Further, in the above example, the detection target is the force of a human finger, but it is needless to say that other pressures may be used.

  FIG. 3 shows a circuit diagram of an example of the detection circuit unit together with the pressure sensor 10. In the figure, the same components as those in FIG. In FIG. 3, the detection circuit unit 28 includes an operational amplifier OP having a non-inverting input terminal connected to the lower electrode 13 and an inverting input terminal connected to the upper electrode 15, and an output terminal of the operational amplifier OP to the inverting input terminal. The resistor R and the capacitor C are connected in parallel to the negative feedback path.

  In the operational amplifier OP, a signal corresponding to the output charge generated by the piezoelectric thin film 14 from the electrode pads 17a and 17b (voltage obtained by dividing the output charge by the capacitance of the measurement system) is input to the inverting input terminal and the non-inverting input terminal. The signal is amplified with a low-pass frequency characteristic having a cutoff frequency corresponding to the reciprocal of the product of the resistance value of the resistor R and the capacitance value of the capacitor C, and the amplified voltage Vout is output as a pressure detection signal to the output terminal 29. Output to. The cut-off frequency is appropriately selected according to the application of the pressure sensor 10. For example, when the block 21 is operated by a human hand, the movement of the hand is at most about several Hz to several tens Hz, so the above-described cutoff frequency may be about 0.15 kHz, for example.

  FIG. 4 shows an applied force versus output charge characteristic diagram of an example of the pressure sensor 10. In the figure, the horizontal axis indicates the force (unit N) applied to the flexible non-conductive resin 19 of the pressure sensor 10, and the vertical axis is output between the electrode pads 17 a and 17 b of the pressure sensor 10. The output charge (unit pC) is shown. As shown in the figure, the pressure sensor 10 can detect even a force (1 to 10 N) large enough to be touched by a human. Here, assuming that the flexible non-conductive resin 19 is PDMS, the hardness of PDMS varies depending on the mixing ratio of the main agent and the curing agent, and becomes harder as the mixing ratio of the curing agent increases. In FIG. 4, I indicates a characteristic curve when the hardness of the PDMS is the hardest, III indicates a characteristic curve when the hardness of the PDMS is the softest, and II indicates a characteristic curve of the intermediate hardness.

  As can be seen from FIG. 4, the higher the hardness of PDMS as an example of the flexible non-conductive resin 19, the larger the output charge (and voltage) is obtained for the same applied force. In addition, the characteristic curve I when the hardness of the PDMS is hard shows the characteristic that an output charge (and voltage) almost linear with respect to the applied force is obtained, and the characteristic curve III when the hardness of the PDMS is soft is It shows the characteristic that the change of the output charge (and voltage) with respect to the applied force is small. Therefore, the hardness of the flexible non-conductive resin 19 is selected according to the application of the pressure sensor 10. For example, in the case of an application where it is desired to obtain a linear detection output with respect to a wide range of pressure, the flexible non-conductive resin 19 is set to a hardness that allows the characteristic curve I to be obtained. On the other hand, if it is desired to detect the pressure in a relatively narrow range and if priority is given to preventing the cantilever portion 12 from being destroyed when a strong force is applied, the flexible non-conductive resin 19 has the characteristic curves II and III. It is set to a soft hardness as obtained.

  Thus, according to the pressure sensor 10 of the present embodiment, a force (1 to 10 N) that is large enough to be touched by a human can be detected without destroying the cantilever portion 12. In addition, according to the pressure sensor 10 of the present embodiment, a pressure sensor having an optimum detection range according to the application can be configured, and only when a force is applied without constantly applying voltage to the pressure sensor 10. Since the pressure is detected using the piezoelectric thin film 14 that generates the output charge, energy saving can be realized as compared with a conventional piezoresistive pressure sensor that measures a change in resistance value while applying a voltage. Furthermore, according to the pressure sensor 10 of this embodiment, since it is the structure to which MEMS technology is applied, compared with the pressure sensor using the conventional strain gauge, a sensor can be reduced in size as shown in FIG.

  5A and 5B are schematic external views of an actual example of the sensor device according to the present invention. The present embodiment shown in FIGS. 5A and 5B is a pressure sensor 100 having a size smaller than the tip of a human finger 104 as shown in FIG. As shown in (B), for example, the plane has a cubic shape of about 5 mm square and a thickness of about 1.2 mm. Further, as shown in the photograph of FIG. 5B, the pressure sensor 100 has a cantilever portion 101 at the center, and the entire structure including the circuit board 102 is embedded in a flexible transparent PDMS 103. It is.

Next, an embodiment of a method for manufacturing a sensor device according to the present invention will be described in detail with reference to the drawings.
6 to 11 are respectively element sectional views or plan views of respective steps of an embodiment of a method for manufacturing a sensor device according to the present invention. In the drawings, the same components are denoted by the same reference numerals. First, as shown in the sectional view of FIG. 6, a silicon oxide film 34 is formed on a SOI (Silicon On Insulator) substrate having a structure in which a silicon substrate 31, a silicon oxide film 32, and a silicon structure 33 are stacked by a known method. The electrode layer 35, the piezoelectric thin film layer 36, and the electrode layer 37 are sequentially stacked.

  Subsequently, as shown in the cross-sectional view of FIG. 7A and the plan view of FIG. 7B, the stacked portion above the silicon structure 33 is shorter than the longitudinal length of the plane of the silicon substrate 31, In addition, the thin silicon oxide film 38 and the lower electrode 39 are formed by etching so that a linear portion narrower than the width in the short direction remains in the central portion on the silicon substrate 31. The piezoelectric thin film layer 36 and the electrode layer 37 are etched so that the lower electrode 39 is exposed at a predetermined region from one end portion, thereby forming the piezoelectric thin film 40 and the upper electrode 41. Subsequently, the electrode pad 42 is formed on the exposed surface of the lower electrode 39, and the electrode pad 43 is formed at an arbitrary position on the surface of the upper electrode 41.

  As a result, as shown in the plan view of FIG. 7B, the center of the upper surface of the silicon structure 33 extends in the same direction as the longitudinal direction of the silicon structure 33 and is wider than the width of the silicon structure 33. In addition, a narrow portion 44 is formed, which is a narrow I-plane planar I-shaped silicon oxide film 38, lower electrode 39, piezoelectric thin film 40, and upper electrode 41 with electrode pads 42 and 43 formed thereon. The lower electrode 39, the piezoelectric thin film 40, and the upper electrode 41 correspond to the lower electrode 13, the piezoelectric thin film 14, and the upper electrode 15 in FIG.

  Next, as shown in the cross-sectional view of FIG. 8A and the plan view of FIG. 8B, the silicon oxide film 32 and the silicon structure 33 on the silicon substrate 31 are formed into the planar I-shaped elongated shape. The groove portion 45 is formed by etching away the portion 44 and a part in the longitudinal direction. Subsequently, as shown in the cross-sectional view of FIG. 9A and the plan view of FIG. 9B, the silicon in the range from the left side portion to the groove portion 45 of the electrode pad 43 of the elongated I-shaped elongated portion 44 described above. A groove 46 is formed in the silicon substrate 31 by etching away the portion of the substrate 31.

  As a result, as shown in FIGS. 9A and 9B, the left side portion of the planar I-shaped elongated portion 44 from the electrode pad 43 exists in the air, and the right side portion of the electrode pad 43 is supported by the silicon substrate 31. The elongated cantilever portion 47 is formed. The cantilever portion 47 has a planar I-shape with a cantilever structure in which the tip portion on the left side of the electrode pad 43 of the elongated portion 44 is a free end that can vibrate and the tip portion on the right side of the electrode pad 43 is a fixed end that cannot vibrate. It is a cantilever part. The cantilever portion 47 corresponds to the second cantilever portion 12b in particular of the cantilever portion 12 of FIG.

  Subsequently, as shown in the cross-sectional view of FIG. 10, the bottom surface of the silicon substrate 31 of the cantilever portion 47 described with reference to FIGS. 9A and 9B is fixed onto the circuit board 48 by die bonding. The lower electrode pad 42 and the upper electrode 43 are connected to the upper electrode pads 49a and 49b by bonding wires 50a and 50b. Thereafter, as shown in the cross-sectional view of FIG. 11, the entire configuration of the element of FIG. 10 is sealed with a flexible non-conductive resin 51 such as silicon rubber, thereby completing the manufacture of the sensor device 52. The circuit board 48 corresponds to the circuit board 18 in FIG. 1, and the flexible non-conductive resin 51 corresponds to the flexible non-conductive resin 19 in FIG. The sensor device 52 is pressed in accordance with the operation principle described with reference to FIG. 2 by pressing a force in the direction of the cantilever portion 47 directly or through a block against the upper surface of the flexible non-conductive resin 51. It functions as a pressure sensor that outputs a detection signal corresponding to the pressure.

  In addition, this invention is not limited to the above embodiment, A to-be-detected object may be other than a pressure. For example, the sensor device 52 shown in FIG. 11 can be used as a vibration sensor or a power generation element 55 as shown in the sectional view of FIG. In the figure, the same components as those in FIG. 11 are denoted by the same reference numerals, and the description thereof is omitted. In FIG. 12, the vibration sensor or power generation element 55 fixes the upper electrode 43 side to the vibrating body 56. As a result, the vibration generated in the vibrating body 56 propagates in the order of the flexible non-conductive resin 51 and the silicon structure 33, and the cantilever portion 47 bends and vibrates according to the vibration to bend into the piezoelectric thin film 40. An output charge of a value corresponding to the amount is generated, and the value of the voltage obtained by dividing the output charge and further the output charge by the capacitance of the measurement system changes according to the vibration of the cantilever 47, and the output charge and A change in voltage value is detected by the circuit board 48. In a conventional vibration sensor that is not sealed with a flexible non-conductive resin, the circuit board side is fixed to the vibrating body.

  In addition, the detection unit in the present invention is not limited to the cantilever units 12 and 47 as described above, but a rod-like silicon substrate spanned between the left and right bases 61a and 61b as shown in FIG. In addition, the piezoelectric thin film laminated portion 62 is bent by the applied pressure to detect a pressure and generate an electrical signal, or a thin-walled portion as shown in FIG. Since the thin wall portion is bent by the pressure, it is also possible to use a diaphragm 63 that generates an electric signal corresponding to the amount of bending in the piezoelectric thin film.

  The sensor device of the present invention can be used in an input device that is installed in a personal computer, a smart phone, a portable information terminal, or the like and inputs characters, symbols, and the like. Also, an input device for a controller such as a game, a robot skin, and the like It can be used as a contact detection sensor.

10, 52, 100 Pressure sensor 11 Silicon substrate 12, 47, 101 Cantilever part 12a First cantilever part 12b Second cantilever part 13, 39 Lower electrode 14, 40 Piezoelectric thin film 15, 41 Upper electrode 16a, 16b, 50a, 50b Bonding wires 17a, 17b, 42, 43, 49a, 49b Electrode pads 18, 48, 102 Circuit board 19, 51 Flexible non-conductive resin 28 Detection circuit part 31 Silicon substrates 32, 34, 38 Silicon oxide film 33 Silicon Structures 35 and 37 Electrode layer 36 Piezoelectric thin film layer 44 Elongated portion 52 Sensor device 55 Vibration sensor or power generation element 56 Vibration body 103 PDMS

Claims (8)

A detector that mechanically deforms in response to an input of the detection target and generates an electrical signal in accordance with the amount of deformation;
A support part for supporting the detection part;
A detection circuit unit that generates a detection signal according to a signal amount of the electrical signal from the detection unit;
A flexible non-conductive resin that seals the entire element including the detection unit, the support unit, and the detection circuit unit, and detects an input of the detection target input through the flexible non-conductive resin. A sensor device. The detector is
A piezoelectric thin film is formed on an elongated flat rectangular parallelepiped substrate in which one of both ends in the longitudinal direction is fixed by the support portion and the other is a free end that can vibrate. The sensor device according to claim 1, wherein the sensor device is a cantilever portion that detects the amount of bending of the substrate that is bent by the input of the piezoelectric thin film and generates the electrical signal. The detector is
A piezoelectric thin film is formed on an elongated flat rectangular substrate whose both ends in the longitudinal direction are fixed by the support portion, and the amount of bending of the substrate that is bent by an input from the detection target is determined by the piezoelectric The sensor device according to claim 1, wherein the sensor device is a bridge unit that detects the thin film and generates the electrical signal. The detector is
The sensor device according to claim 1, wherein the sensor device is a diaphragm portion that generates an electric signal by detecting a bending of a thin portion bent by an input from the detection target with a piezoelectric thin film. A piezoelectric thin film is formed on a long and flat rectangular parallelepiped substrate in which one of both end portions in the longitudinal direction is a fixed end and the other is a free end, and the free end is formed according to an applied pressure. The cantilever part in which the piezoelectric thin film generates an output charge corresponding to the bending amount;
A support portion for fixing the fixed end of the cantilever portion;
A detection circuit unit that generates a pressure detection signal corresponding to an applied pressure from the output charge generated by the piezoelectric thin film;
A flexible non-conductive resin that seals the entire element including the cantilever part, the support part, and the detection circuit part, and detecting the input of the pressure input through the flexible non-conductive resin. A characteristic sensor device.   The support part is configured by the silicon substrate of an SOI substrate in which a silicon substrate, a silicon oxide film, and a silicon structure are stacked in this order, and the substrate of the cantilever part is the silicon oxide film and the silicon of the SOI substrate. 6. The sensor device according to claim 3, wherein the sensor device is formed of a laminated body of structures.   The said flexible nonelectroconductive resin is set so hard that the hardness expands the linear detection range of the said to-be-detected object, The one of Claims 1 thru | or 6 characterized by the above-mentioned. Sensor device. A forming step of forming a cantilever portion in which a piezoelectric thin film is formed on a long and flat rectangular parallelepiped substrate in which one of both longitudinal end portions is fixed by a support portion and the other is a free end;
A fixing step of fixing a bottom surface of the support portion of the cantilever portion on a circuit board of the detection circuit portion;
A wiring step of wiring between the first electrode pad of the driving electrode of the piezoelectric thin film of the cantilever part and the second electrode pad on the circuit board;
And a sealing step of sealing the entire element including the cantilever portion and the circuit board that has undergone the wiring step with a flexible non-conductive resin.

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