JP7176986B2 - SURFACE STRESS SENSOR, SURFACE STRESS SENSOR INSPECTION METHOD, SURFACE STRESS SENSOR MANUFACTURER - Google Patents

Description

The present invention provides a membrane-type surface stress sensor (MSS) that reduces current consumption and assembly costs compared to conventional piezoresistive cantilever surface stress sensors, a surface stress sensor inspection method, and a surface stress sensor manufacturing method. Regarding.

As a technology used for a sensor that collects information corresponding to the five human senses, in particular, a sensor for the sense of taste and smell that humans feel when they receive chemical substances, for example, there is a piezoresistive surface sensor disclosed in Patent Document 1.
The piezoresistive surface sensor disclosed in Patent Literature 1 is a film-type surface stress sensor that detects mechanical deformation and stress of a detection member caused by an object to be measured by means of a change in the resistance value of the piezoresistor. The piezoresistive surface sensor disclosed in Patent Document 1 detects changes in the resistance value of the piezoresistors using changes in voltage detected by a full bridge circuit (full Wheatstone bridge) formed by four resistors.

JP 2015-45657 A

However, in the full-bridge circuit, since a bias voltage is applied to the bridge resistors, the current consumption of the surface stress sensor is large. Moreover, the surface stress sensor must be provided with a terminal for applying a bias voltage in addition to the output terminal.

The present invention has been made by focusing on the unsolved problems of the prior art. An object of the present invention is to provide an inspection method and a method of manufacturing a surface stress sensor.

To achieve the above object, a surface stress sensor according to one aspect of the present invention includes a conductive membrane, a conductive frame member, at least a pair of conductive connecting portions, and a conductive support base material. , a receptor, and an insulator. The membrane flexes due to applied surface stress. The frame member is spaced apart from the membrane when viewed in the thickness direction of the membrane and surrounds the membrane. The connecting portions are arranged at at least two positions sandwiching the membrane when viewed in the thickness direction of the membrane, and connect the membrane and the frame member. The supporting substrate is connected to the frame member and arranged with a gap between the membrane and the connecting portion, and overlaps the membrane and the connecting portion when viewed from the thickness direction of the membrane. The receptor is formed on a region including the center of the surface of the membrane opposite to the surface facing the supporting substrate, and deforms according to the adsorbed substance. The insulating portion is provided between the frame member and the supporting base material, and electrically insulates the frame member from the supporting base material. Also, the connecting portion bends due to the deformation of the membrane that follows the deformation of the receiver. In addition, the capacitance between the membrane and connection and the supporting substrate changes with the bending of the connection.

Further, a method for inspecting a surface stress sensor according to another aspect of the present invention is a surface stress sensor including a first terminal electrically connected to a membrane and a second terminal electrically connected to a support base. is an inspection method for inspecting the operation of the membrane. A method for inspecting a surface stress sensor includes a second voltage application step, an inspection-time capacitance detection step, and a judgment step. The second voltage applying step is a step of applying a second voltage between the first terminal and the second terminal. The test-time capacitance detection step is a step of detecting a test-time capacitance, which is the capacitance in a state where the second voltage is applied between the first terminal and the second terminal. In the determination step, the capacitance during inspection detected in the capacitance detection step during inspection and the electrostatic capacitance in a state where a first voltage different from the second voltage is applied between the first terminal and the second terminal a reference capacitance, which is capacitance, and determining the operation of the membrane.

A method of manufacturing a surface stress sensor according to another aspect of the present invention includes a laminate forming step, a first electrode forming step, a low resistance region forming step, a removing step, and a wiring layer forming step. The laminate forming step is a step of forming a concave portion on one surface of the supporting substrate and forming an insulating portion on one surface. Further, in the laminate forming step, the detection base material is attached so as to cover the part of the support base material where the insulating part is formed, thereby forming a laminate in which a gap is provided between the support base material and the detection base material. It is the process of forming the body. In the first electrode forming step, a part of the detection base material and the insulating part is removed to form a through hole penetrating from the surface of the detection base material opposite to the surface facing the support base material to the support base material. It is a process to do. Further, the step of forming the first electrode is a step of filling the through holes with an electrode material containing impurities to form the first electrode reaching from the surface to the supporting substrate. In the low-resistance region forming step, ions are implanted into a predetermined region on the surface of the detection base material, and then the laminate with the first electrode formed thereon is heat-treated to fix impurities from the first electrode to the support base material. phase diffusion to form a first low-resistance region in the ion-implanted region of the sensing substrate and a second low-resistance region in the supporting substrate; The removing step is a step of forming a membrane, a frame member, and at least a pair of connecting portions by removing a region around a preset region including the center of the detection substrate and other than the first low-resistance region. be. The wiring layer forming step is a step of forming a wiring layer including first terminals electrically connected to the membrane and second terminals electrically connected to the supporting base material.

A method for manufacturing a surface stress sensor according to another aspect of the present invention includes a laminate forming step, a first electrode forming step, a low resistance region forming step, a hole forming step, a gap forming step, and a hole sealing step. It includes a stopping step, a removing step, and a wiring layer forming step. The laminate forming step is a step of laminating an insulating sacrificial layer on the support base material and further laminating the detection base material on the sacrificial layer to form a laminate. The first electrode forming step is a step of removing a part of the detection base material and forming a through hole penetrating from the surface of the detection base material opposite to the surface facing the support base material to the support base material. be. Further, the step of forming the first electrode is a step of filling the through holes with an electrode material containing impurities to form the first electrode reaching from the surface to the supporting substrate. In the low-resistance region forming step, ions are implanted into a predetermined region on the surface of the detection base material, and then the laminate with the first electrode formed thereon is heat-treated to fix impurities from the first electrode to the support base material. phase diffusion to form a first low-resistance region in the ion-implanted region of the sensing substrate and a second low-resistance region in the supporting substrate; The hole forming step is a step of forming a hole penetrating to the sacrificial layer in a preset region including the center of the detection substrate in the detection substrate. In the gap forming step, a sacrificial layer disposed between a predetermined region including the center of the detection base material and the support base material is removed by etching through the hole to separate the support base material and the detection base material. This is a step of providing a gap between them. Further, in the gap forming step, an insulating portion is formed between the detection substrate and the support substrate at a position where the sacrificial layer remains and electrically insulates the detection substrate and the support substrate. It is a process to do. The hole sealing step is a step of forming an oxide film on the surface of the detection substrate opposite to the surface facing the support substrate to seal the hole. The removing step is a step of forming a membrane, a frame member, and at least a pair of connecting portions by removing a region around a preset region including the center of the detection substrate and other than the first low-resistance region. be. The wiring layer forming step is a step of forming a wiring layer including first terminals electrically connected to the membrane and second terminals electrically connected to the supporting base material.

According to one aspect of the present invention, it is possible to detect an object by detecting a change in capacitance between the membrane/connecting portion and the support base material.
As a result, a surface stress sensor capable of reducing current consumption and assembly cost compared to a surface sensor that detects an object to be measured by detecting a change in the resistance value of a piezoresistor, and an inspection method for the surface stress sensor. , it is possible to provide a method for manufacturing a surface stress sensor.

It is a side view showing composition of a surface stress sensor concerning a first embodiment of the present invention. FIG. 2 is a view taken along line II of FIG. 1; 3 is a cross-sectional view taken along line III-III of FIG. 2; FIG. FIG. 3 is a sectional view taken along line IV-IV of FIG. 2; 4 is a diagram showing the configuration of a capacitance change detection section; FIG. 3 is a diagram showing the configuration of a current detection circuit; FIG. It is a flow chart which shows the first inspection method. It is a flow chart which shows a second inspection method. It is a flow chart which shows a third inspection method. It is a figure which shows a laminated body formation process. It is a figure which shows a 1st electrode formation process. It is a figure which shows a 1st electrode formation process. It is a figure which shows a 1st electrode formation process. It is a figure which shows a low-resistance area|region formation process. It is a figure which shows a wiring layer formation process. It is a figure which shows a wiring layer formation process. It is a figure which shows a wiring layer formation process. It is a figure which shows a wiring layer formation process. It is a figure which shows the operation|movement and effect|action of the surface stress sensor of 1st embodiment. It is a figure which shows the modification of 1st embodiment. It is a figure which shows the modification of 1st embodiment. FIG. 22 is a cross-sectional view taken along line YY of FIG. 21; It is a figure which shows the modification of 1st embodiment. FIG. 24 is a cross-sectional view taken along line ZZ of FIG. 23; FIG. 5 is a side view showing the configuration of a surface stress sensor according to a second embodiment of the present invention; It is a figure which shows a laminated body formation process. It is a figure which shows a 1st electrode formation process. It is a figure which shows a 1st electrode formation process. It is a figure which shows a 1st electrode formation process. It is a figure which shows low resistance area|region formation. It is a figure which shows a hole formation process. It is a figure which shows a void|gap part formation process. It is a figure which shows a hole sealing process. It is a figure which shows a wiring layer formation process.

Embodiments of the invention are described below with reference to the drawings. In the description of the drawings referred to in the following description, the same or similar parts are given the same or similar reference numerals. However, it should be noted that the drawings are schematic, and the relationship between thickness and planar dimensions, the ratio of thicknesses, etc. are different from the actual ones. Therefore, specific thicknesses and dimensions should be determined with reference to the following description. In addition, it goes without saying that there are portions with different dimensional relationships and ratios between the drawings.

Further, the embodiments shown below are examples of configurations for embodying the technical idea of the present invention. It does not specify the layout, etc., to the following. Various changes can be made to the technical idea of the present invention within the technical scope defined by the claims. Further, the directions of "left and right" and "up and down" in the following description are merely definitions for convenience of description, and do not limit the technical idea of the present invention. Therefore, for example, if the page is rotated 90 degrees, "left and right" and "up and down" are read interchangeably, and if the page is rotated 180 degrees, "left" becomes "right" and "right" becomes "left". Of course it will be.

(First embodiment)
A first embodiment of the present invention will be described below with reference to the drawings.
(Constitution)
The configuration of the first embodiment will be described with reference to FIGS. 1 to 6. FIG.
A surface stress sensor 1 shown in FIGS. 1 to 4 is, for example, a sensor that detects taste and smell. Further, the surface stress sensor 1 includes a package substrate 2, a connection portion 4, a support base material 10, a detection base material 20, an insulating portion 6, a first terminal 50, a second terminal 52, and a first electrode. 54 and a capacitance change detection unit 100 . In FIG. 2, illustration of the package substrate 2 and the connecting portion 4 is omitted for the sake of explanation.

(package substrate)
The package substrate 2 is made of, for example, a metal, polymer, ceramic material, or the like, and has a thickness on the order of millimeters, for example.
(connection part)
The connecting portion 4 is arranged on one surface (the upper surface in FIG. 1) of the package substrate 2, and is formed using an adhesive, solder, or the like, for example.
In the first embodiment, as an example, a case where the shape of the connection portion 4 is formed in a circle will be described.

(Support base material)
The support base material 10 is conductive and functions as a fixed electrode of the surface stress sensor 1 .
Further, the supporting base material 10 is arranged on one surface of the package substrate 2 and attached to the package substrate 2 via the connecting portion 4 .
In the first embodiment, as an example, the case where the center of the supporting base material 10 overlaps the position where the connecting portion 4 is arranged will be described.

The area of the support base 10 (in FIG. 1, the area of the support base 10 when the support base 10 is viewed from above) is larger than the area of the connection portion 4 .
The thickness of the supporting base material 10 (the vertical length of the supporting base material 10 in FIG. 1) is set to 80 [μm] or more. The thickness of the supporting base material 10 may be set within a range of 80 [μm] to 750 [μm].

As a material for forming the support substrate 10, for example, a material containing any one of silicon (Si: silicon), sapphire, gallium arsenide, glass, and quartz can be used.
In the first embodiment, as an example, a case where n-type silicon is used as the material forming the support base 10 will be described.
The n-type silicon is obtained by adding a pentavalent element such as arsenic, phosphorus, or antimony to single-crystal silicon as an impurity.

Accordingly, in the first embodiment, the coefficient of linear expansion of the supporting substrate 10 is set to 5.0×10 ⁻⁶ /° C. or less.
The linear expansion coefficients of materials that can be used as materials for forming the support base 10 are described below.
The linear expansion coefficient of silicon is 3.9×10 ⁻⁶ /° C. or less under an environment of normal temperature to 1000° C. or less.
The coefficient of linear expansion of sapphire is 9.0×10 ⁻⁶ /° C. or less in an environment of 0° C. or higher and 1000° C. or lower.

Gallium arsenide (GaAs) has a coefficient of linear expansion of 6.0×10 ⁻⁶ /° C. or less under an environment of 0 K or more and 300 K or less.
The coefficient of linear expansion of glass (float glass) is 8.5×10 ⁻⁶ /° C. or less to 9.0×10 ⁻⁶ /° C. or less in an environment of 0° C. or higher and 300° C. or lower.
The linear expansion coefficient of quartz is 0.59×10 ⁻⁶ /° C. or less in an environment of 0° C. or higher and 300° C. or lower. Note that the coefficient of linear expansion of quartz has a peak near 300.degree.

(Detection substrate)
The detection base material 20 is conductive and functions as a movable electrode of the surface stress sensor 1 .
In addition, the detection substrate 20 is laminated on one surface (the upper surface in FIG. 1) of the support substrate 10, and the membrane 22, the frame member 24, and the connecting portion 26 are integrated. formed.
In the first embodiment, as an example, the case where n-type silicon is used as the material forming the detection substrate 20 will be described.
In addition, as the material forming the detection substrate 20, a material is used in which the difference between the linear expansion coefficient of the support substrate 10 and the linear expansion coefficient of the detection substrate 20 is 1.2×10 ⁻⁵ /° C. or less. .
In the first embodiment, the case where the same material is used for the material forming the detection substrate 20 and the material forming the support substrate 10 will be described.

(membrane)
The membrane 22 is formed in a plate shape.
In the first embodiment, as an example, a case where the membrane 22 is formed in a disc shape will be described. The membrane 22 may be formed in a polygonal shape or a shape surrounded by curved lines, for example.
Also, the membrane 22 is an n-type semiconductor layer.

One surface of the membrane 22 (the upper surface in FIG. 1) is coated with a receptor 30 (receptor). In the following description, one surface of the membrane 22 may be referred to as "the surface of the membrane 22".
A receptor 30 is formed on the receptor-forming region.
The receptor forming area is an area including the center of the surface of the membrane 22 and is set in advance. In addition, since it is preferable that the area to be coated with the receptor 30 is large, the receptor forming region is preferably large.
The receptor 30 (receptor) is formed using, for example, polyethyleneimine, and strain is generated by adsorption of molecules of the measurement object (gas).

When molecules of the object to be measured are adsorbed to the receptor 30 and the receptor 30 is distorted, surface stress is applied to the membrane 22 and the membrane 22 bends. Membrane 22 therefore flexes due to the applied surface stress when gas molecules adsorb to receptors 30 .
The structure of the receptor 30 is not limited to a structure in which distortion is generated by adsorption of gas molecules. For example, a structure in which distortion is generated by magnetism may be used. That is, the configuration of the receptor 30 may be changed as appropriate according to the detection target of the surface stress sensor 1 .

(Frame member)
The frame member 24 is formed in a grid shape, and surrounds the membrane 22 with a gap when viewed from the thickness direction of the membrane 22 .
The viewpoint when viewed from the thickness direction of the membrane 22 is the viewpoint when the surface stress sensor 1 is viewed from above (the viewpoint when viewed from the direction of arrow II in FIG. 1).
The center of the frame member 24 overlaps the center of the membrane 22 when viewed from the thickness direction of the membrane 22 .
The frame member 24 is arranged on the side of the support base 10 opposite to the side facing the package substrate 2 (upper side in FIG. 1) with the insulating portion 6 interposed therebetween. ing.

In the first embodiment, as an example, when the shapes of the frame member 24 and the support base material 10 are viewed from the thickness direction of the membrane 22, the outer peripheral surface of the support base material 10 and the outer peripheral surface of the frame member 24 are flush with each other. A case of forming in a certain shape will be described.
That is, the frame member 24 and the support base 10 have the same quadrilateral shape when viewed from the thickness direction of the membrane 22 . This is achieved, for example, by performing a dicing process on the frame member 24 and the support base material 10 after connecting the frame member 24 and the support base material 10 . That is, the center of the frame member 24 overlaps the center of the support base 10 when viewed from the thickness direction of the membrane 22 .

Therefore, the supporting base material 10 overlaps the membrane 22 and the frame member 24 when viewed from the thickness direction of the membrane 22 .
Furthermore, the connecting portion 4 is arranged at a position overlapping at least a portion of the membrane 22 when viewed in the thickness direction of the membrane 22 .
In addition, the area of the connection portion 4 is smaller than the area of the membrane 22 when viewed from the thickness direction of the membrane 22 .
The package substrate 2 is connected to the surface of the support base 10 opposite to the surface facing the membrane 22 (lower surface in FIG. 1).

(Connecting part)
The connecting portion 26 is formed in a strip shape when viewed from the thickness direction of the membrane 22 .
In addition, the connecting portion 26 is arranged at a position overlapping imaginary straight lines VL1 and VL2 passing through the center of the membrane 22 when viewed from the thickness direction of the membrane 22, and connects the membrane 22 and the frame member 24. ing.

In the first embodiment, as an example, a case where the membrane 22 and the frame member 24 are connected by two pairs of four connecting portions 26a to 26d will be described.
The four connecting portions 26a to 26d are a pair of connecting portions 26a and 26b arranged at positions overlapping with the straight line VL1, and a pair of connecting portions 26c arranged at a position overlapping with a straight line VL2 orthogonal to the straight line VL1. and connecting portion 26d.

That is, the pair of connecting portions 26a and 26b and the pair of connecting portions 26c and 26d are arranged at at least two positions sandwiching the membrane 22 when viewed from the thickness direction of the membrane 22. 22 and the frame member 24 are connected.
In the first embodiment, as an example, the case where the width of the connecting portion 26a and the connecting portion 26b is narrower than the width of the connecting portion 26c and the connecting portion 26d will be described.

A gap portion 40 is provided between the membrane 22 and the four connecting portions 26 a to 26 d and the supporting base material 10 .
Therefore, the supporting base material 10 is connected to the frame member 24 and arranged with a gap (a gap portion 40 ) between the membrane 22 and the connecting portion 26 . In addition, the supporting substrate 10 overlaps the membrane 22 and the connecting portion 26 when viewed from the thickness direction of the membrane 22 .

In addition, when the surface stress sensor 1 is used in a solution, the space 40 may be filled with the solution.
The void 40 functions as a space that prevents the membrane 22 from sticking to the support base 10 when the membrane 22 bends toward the support base 10 during processing of the detection base 20 .
In addition, the void 40 functions as a space for forming capacitance between the membrane 22 and the connecting portion 26 and the support base 10 .

(Insulating part)
The insulating portion 6 is provided between the support base 10 and the frame member 24 to electrically insulate the support base 10 and the detection base 20 .
Moreover, the insulating portion 6 is formed of, for example, a silicon oxide film.
A portion of the insulating portion 6 surrounds the second terminal 52 when viewed from the thickness direction of the membrane 22 . Moreover, the insulating portion 6 except for the portion surrounding the second terminal 52 when viewed in the thickness direction of the membrane 22 is arranged between the support base 10 and the frame member 24 .

(first terminal)
The first terminal 50 is made of a metal material such as Al, and is electrically connected to the membrane 22 .
(Second terminal)
The second terminal 52 is formed using a metal material such as Al through the first electrode 54 and is electrically connected to the support base 10 .

(first electrode)
The first electrode 54 is formed using an electrode material containing impurities, and is the surface of the detection substrate 20 opposite to the surface facing the support substrate 10 (surface of the detection substrate 20). , to reach the supporting substrate 10 .

(Capacitance change detector)
A detailed configuration of the capacitance change detection unit 100 will be described below.
The capacitance change detection section 100 detects a change in capacitance between the membrane 22 and the connecting portion 26 and the support base 10 .
5, the capacitance change detection section 100 includes a power source 110, a current detection circuit 120, a storage section 130, a difference calculation section 140, and a sensitivity correction section 170. FIG.

A power source 110 is connected to the first terminal 50 via a current detection circuit 120 and applies DC and AC voltages to the membrane 22 and the coupling portion 26 . Furthermore, the power source 110 is connected to the second terminal 52 and applies a DC voltage and an AC voltage to the support substrate 10 . Therefore, the power source 110 applies a DC voltage and an AC voltage between the membrane 22 and the connecting portion 26 and the supporting substrate 10 .
Current detection circuit 120 detects the current current corresponding to the capacitance between membrane 22 and connecting portion 26 and support substrate 10 .

6, the current detection circuit 120 includes an operational amplifier 120a, a resistor 120b, a capacitor 120c, a multiplier 120d, a low-pass filter 120e, and an A/D converter 120f.
The operational amplifier 120a has an inverting input terminal connected to the second terminal 52 and a non-inverting input terminal grounded.
A resistor 120b and a capacitor 120c are connected in parallel with the operational amplifier 120a.
The multiplier 120d is connected to the power supply 110 and the output terminal of the operational amplifier 120a.
The input side of the low-pass filter 120e is connected to the output side of the multiplier 120d.
The input side of the A/D converter 120f is connected to the output side of the low-pass filter 120e. The output side of the A/D converter 120f is connected to the storage section 130 and the difference calculation section 140. FIG.

The storage unit 130 is stored in advance in a state in which the molecules of the measurement object (gas) are not adsorbed to the receptor 30 (when the measurement object is not detected), and the space between the membrane 22 and the connecting part 26 and the supporting base material 10 is stored. A current corresponding to the capacitance _C0 is stored.
The capacitance _C0 is given by the following equation (1).

In formula (1), ε0 is the dielectric constant in vacuum, εr is the relative dielectric constant of the void 40, d is the distance between the membrane 22 and the connecting portion 26 and the support base 10, and A is the membrane 22 and the connecting portion. This is the area of the portion where 26 and the supporting base material 10 face each other.

In addition, the storage unit 130 stores a reference capacitance, an inspection-time capacitance, and a sensitivity correction value.
The reference capacitance is the capacitance when the first voltage is applied between the first terminal 50 and the second terminal 52 .
The capacitance under test is the capacitance when a second voltage different from the first voltage is applied between the first terminal 50 and the second terminal 52 .
The sensitivity correction value is a sensitivity correction value calculated from the reference capacitance and the testing capacitance.

The difference calculation unit 140 calculates the capacitance C ₀ stored in the storage unit 130 and the membrane 22 in the state where the molecules of the measurement object (gas) are adsorbed to the receptor 30 (when the measurement object is detected). and the difference between the electric current corresponding to the capacitance C1 between the connecting portion 26 and the support base ₁₀ is calculated.
The capacitance C1 is given by equation ( ₂ ) below.

In Equation (2), Δd is the value of the membrane 22 and the coupling, which increases due to the bending of the coupling portion 26 due to the deformation of the membrane 22 when the object to be measured is detected, that is, when gas molecules are adsorbed on the receptor 30 . It is the distance between the portion 26 and the support substrate 10 .
Specifically, when the object to be measured is detected, that is, when gas molecules are adsorbed on the receptor 30 , the receptor 30 is deformed and surface stress is applied to the membrane 22 , causing the membrane 22 to follow the deformation of the receptor 30 . deforms (bends). When the membrane 22 is deformed, the deformation of the membrane 22 bends the connecting portion 26 , and the distance between the membrane 22 and the connecting portion 26 and the supporting substrate 10 increases from d to Δd.

As the distance between membrane 22 and connection 26 and support substrate 10 increases from d to Δd, the capacitance between membrane 22 and connection 26 and support substrate 10 goes from C ₀ to C ₁ . Change.
The difference calculated by the difference calculator 140 is output to a computer (not shown) or the like. A computer or the like detects the object to be measured by reading the change in current value according to the change in capacitance (C ₁ -C ₀ ).
Therefore, when the object to be measured is detected, the capacitance between the membrane 22 and the connecting portion 26 and the support base 10 changes according to the composition of the object to be measured. Therefore, by detecting the change in capacitance (C ₁ -C ₀ ), it is possible to detect the surface stress caused by the deflection of the membrane 22 and detect the object to be measured.

Further, the difference calculation unit 140 calculates the difference between the reference capacitance and the inspection capacitance. Then, the difference calculation unit 140 outputs the difference between the reference capacitance and the testing capacitance and the sensitivity correction value stored in the storage unit 130 to a computer or the like (not shown). The computer or the like uses the difference between the reference capacitance and the testing capacitance to determine whether the membrane 22 is malfunctioning. Furthermore, the sensitivity correction section 170 corrects the output result from the difference calculation section 140 according to the sensitivity correction value stored in the storage section 130 .

(Inspection method for surface stress sensor)
A method for inspecting the surface stress sensor 1 will be described using FIGS. 7 to 9 while referring to FIGS. 1 to 6. FIG.
The surface stress sensor 1 is inspected, for example, during a factory inspection of the surface stress sensor 1 (at the time of manufacture, shipment, etc.) or during use by the user.

First, referring to FIGS. 1 to 6, using FIG. 7, a method of inspecting the surface stress sensor 1 during manufacturing, etc., during factory inspection (hereinafter referred to as “first inspection method”). may be used) will be described. The first inspection method includes, for example, a step of forming the membrane 22, a step (dicing) of cutting a plurality of laminates of the support substrate 10 and the detection substrate 20 formed in a sheet shape, a process (dicing), This is done to detect defects that occur in the process of applying
As shown in FIG. 7, in the first inspection method, in step S10, a first voltage is applied between the first terminal 50 and the second terminal 52 from the power supply 110, and the current detection circuit 120 is turned on, for example. is used to measure the offset voltage.
The first voltage is, for example, an AC voltage with minute amplitude.
Next, in step S11, the current detection circuit 120 is used to measure the reference capacitance, which is the capacitance corresponding to the offset voltage.
Here, the “offset voltage” is the voltage output by the capacitance change detection unit 100 for the capacitance between the first terminal 50 and the second terminal 52 when the membrane 22 is not deformed (flat plate). and is usually 0 [V].

Next, in step S<b>12 , a second voltage different from the first voltage is applied from the power supply 110 between the first terminal 50 and the second terminal 52 .
The second voltage is, for example, a DC voltage and an AC voltage with minute amplitude.
After that, in step S13, with the second voltage applied between the first terminal 50 and the second terminal 52, the current detection circuit 120 is used to inspect the capacitance corresponding to the second voltage. Measure the time capacitance.

Then, in step S14, it is determined whether or not the membrane 22 is malfunctioning according to the change in the reference capacitance measured in step S11 and the testing capacitance measured in step S13. After that, the first inspection method ends.
For the surface stress sensor 1 for which the membrane 22 is determined to be malfunctioning, for example, the structure is corrected.

As described above, the inspection method (first inspection method) for the surface stress sensor 1 is an inspection method for inspecting the operation of the membrane 22 with respect to the surface stress sensor 1, and includes the second voltage application step and the capacitance detection during inspection. and a determination step. In addition, in the inspection method (first inspection method) of the surface stress sensor 1, a current is detected when a DC voltage and an AC voltage having a minute amplitude are applied between the first terminal 50 and the second terminal 52. , detect changes in capacitance and detect defects.

The second voltage applying step (step S12) is a step of applying a preset second voltage between the first terminal 50 and the second terminal 52. FIG.
The test-time capacitance detection step (step S13) is a step of detecting the test-time capacitance. The testing capacitance is the capacitance in a state where the second voltage is applied between the first terminal 50 and the second terminal 52 .

In the determination step (step S14), the capacitance during inspection detected in the capacitance detection step during inspection, and the state in which a preset first voltage is applied between the first terminal 50 and the second terminal 52 This is a step of determining the operation of the membrane 22 based on the reference capacitance, which is the resistance value.
In the determination step, for example, when the difference between the inspection-time capacitance and the reference capacitance exceeds a preset difference threshold value, it is determined that the membrane 22 is operating abnormally. The difference threshold is set to 1.0×10 ⁻¹⁵ [F], for example.

Furthermore, the inspection method (first inspection method) for the surface stress sensor 1 includes a first voltage application step and a measurement step.
The first voltage application step (step S11) is a step preceding the second voltage application step, and applies a first voltage different from the second voltage between the first terminal 50 and the second terminal 52. It is a process.
The measuring step (step S12) is a step of measuring the reference capacitance while applying the first voltage between the first terminal 50 and the second terminal 52 in the first voltage applying step.

Next, while referring to FIGS. 1 to 7, a method of inspecting the surface stress sensor 1 at the time of shipment, etc. during the factory inspection using FIG. may be described) will be described. The second inspection method is used, for example, to detect defects that occur when the surface stress sensor 1 is attached to a contained component detection device, an inspection system, or the like.
The contained component detection device is a device that detects a component contained in the fluid adhering to the receptor 30 . An inspection system is a system that inspects the operation of the membrane 22 .
As shown in FIG. 8, in the second inspection method, in step S20, a first voltage is applied between the first terminal 50 and the second terminal 52 from the power source 110, and the current detection circuit 120 is turned on, for example. is used to measure the offset voltage.

Next, in step S21, the current detection circuit 120 is used to measure the reference capacitance, which is the capacitance corresponding to the offset voltage.
After that, in step S<b>22 , a second voltage different from the first voltage is applied from the power supply 110 between the first terminal 50 and the second terminal 52 .

Next, in step S23, with the second voltage applied between the first terminal 50 and the second terminal 52, the current detection circuit 120 is used to determine the capacitance corresponding to the second voltage. Measure the capacitance during testing.
Then, in step S24, it is determined whether or not the membrane 22 is malfunctioning according to the change between the reference capacitance measured in step S21 and the testing capacitance measured in step S23.

If it is determined in step S24 that the operation of the membrane 22 is defective, the second inspection method ends. For the surface stress sensor 1 for which the membrane 22 is determined to be malfunctioning, for example, the structure is corrected.
On the other hand, if it is determined in step S24 that the operation of the membrane 22 is not defective, in step S25, the sensitivity corresponding to the change in the reference capacitance measured in step S21 and the test capacitance measured in step S23 A sensitivity correction value that is a correction value for is calculated.

Next, in step S26, the sensitivity correction value calculated in step S25 is stored in the storage unit 130. FIG.
Then, in step S27, the sensitivity correction unit 150 is adjusted using the sensitivity correction value stored in the storage unit 130 in step S26. After that, the second inspection method ends.

As described above, the inspection method (second inspection method) for the surface stress sensor 1 further includes the correction value calculation step, the correction value storage step, and the sensitivity correction unit adjustment step in addition to the first inspection method.
In the correction value calculation step (step S25), when it is determined in the determination step (step S24) that the operation of the membrane is better than the reference value, the reference electrostatic capacitance detected in the reference capacitance detection step (step S21) This is a step of calculating a sensitivity correction value, which is a sensitivity correction value corresponding to the capacitance during inspection detected in the capacitance and capacitance during inspection step (step S23).

The correction value storage step (step S26) is a step of storing the sensitivity correction value calculated in the correction value calculation step.
The sensitivity correction unit adjustment step (step S27) is a step of adjusting the sensitivity correction unit 150 using the sensitivity correction value stored in the correction value storage step.

Next, referring to FIGS. 1 to 8, and using FIG. 9, a method of inspecting the surface stress sensor 1 during use by a user (in the following description, it may be referred to as a "third inspection method"). An example of is explained. The third inspection method is used, for example, to detect malfunction caused by structural destruction due to dropping or vibration when the surface stress sensor 1 is used.
As shown in FIG. 9, in the third inspection method, in step S30, a first voltage is applied between the first terminal 50 and the second terminal 52 from the power supply 110, and the current detection circuit 120 is turned on, for example. is used to measure the offset voltage.

Next, in step S31, the current detection circuit 120 is used to measure the reference capacitance, which is the capacitance corresponding to the offset voltage.
After that, in step S<b>32 , a second voltage different from the first voltage is applied from the power supply 110 between the first terminal 50 and the second terminal 52 .

Next, in step S33, with the second voltage applied between the first terminal 50 and the second terminal 52, the current detection circuit 120 is used to determine the capacitance corresponding to the second voltage. Measure the capacitance during testing.
Then, in step S34, it is determined whether or not the membrane 22 is malfunctioning according to the change between the reference capacitance measured in step S31 and the testing capacitance measured in step S33.

If it is determined in step S34 that the operation of the membrane 22 is not defective, the third inspection method ends.
On the other hand, if it is determined in step S34 that the membrane 22 is malfunctioning, the degree of malfunction of the membrane 22 is determined in step S35. In step S35, for example, when the difference between the inspection-time capacitance and the reference capacitance exceeds a preset pass/fail threshold, it is determined that the degree of failure is high. The pass/fail threshold is set to 5.0×10 ⁻¹⁶ [F], for example. In addition, the difference between the inspection capacitance and the reference capacitance acquired in the factory shipment inspection is stored in the storage unit 130, and the difference between the inspection capacitance and the reference capacitance during use by the user is stored. It is also possible to determine by performing a difference and a comparison.
In the first embodiment, as an example, the pass/fail threshold is set to half the value of the factory inspection as the capacitance change (output change) amount, which is an absolute threshold, but it is not limited to this. That is, for example, the pass/fail threshold may be a relative threshold. In this case, the relative threshold may be defined by, for example, the amount of sensitivity reduction (eg, 50% reduction) from the factory shipment.

If it is determined in step S35 that the degree of defect is high, the third inspection method ends. For the surface stress sensor 1 having the membrane 22 determined to have a high degree of operational failure, for example, the manufacturer performs processing such as modifying the structure.
On the other hand, if it is determined in step S35 that the degree of defect is low, in step S36, a sensitivity correction value, which is a sensitivity correction value corresponding to the capacitance during inspection detected in step S33, is calculated. The membrane 22 determined to have a low degree of operational failure is, for example, the membrane 22 in a state capable of exhibiting the minimum performance required of the surface stress sensor 1 .

Next, in step S37, the sensitivity correction value calculated in step S36 is stored in the storage unit 130. FIG.
Then, in step S38, the sensitivity correction unit 150 is adjusted using the sensitivity correction value stored in the storage unit 130 in step S37. After that, the third inspection method ends.

As described above, the inspection method (third inspection method) for the surface stress sensor 1 further includes the defect degree determination step in addition to the second inspection method.
The defect degree determination step (step S35) is a step of determining the degree of defect in the operation of the membrane 22 based on the capacitance during inspection and the reference capacitance.
When the surface stress sensor 1 is manufactured, for example, the membrane 22 may have a convex shape (deformation) due to residual stress in the membrane 22 or due to stretching of the membrane 22 that occurs when the receptor 30 is dried. in some cases).

As described above, by setting the offset voltage to 0 [V], it is possible to reduce the input range of the differential amplifier.
Therefore, by the second inspection method, the voltage between the membrane 22 and the support base 10 at which the offset voltage is 0 [V] is stored in the storage unit 130 before the surface stress sensor 1 is shipped. This makes it possible to apply the stored voltage in the third inspection method, which is the measurement mode after shipment.

(Manufacturing method of surface stress sensor)
A method of manufacturing the surface stress sensor 1 will be described using FIGS. 10 to 18 while referring to FIGS. 1 to 6. FIG. 10 to 18 correspond to the cross-sectional view taken along line XX in FIG.
The method of manufacturing the surface stress sensor 1 includes a laminate forming step, a first electrode forming step, a low resistance region forming step, a removing step, a wiring layer forming step, and a receptor forming step.

(Laminate forming step)
In the laminate forming step, first, as shown in FIG. 10A, a concave portion 62 (trench) is formed on one surface of a first silicon substrate 60, which is the material of the support base 10, using lithography and etching techniques. Form. The depth of the recess 62 is set to 7 [μm], for example. The first silicon substrate 60 is a conductive n-type silicon substrate.
Next, as shown in FIG. 10B, the insulating portion 6 is formed by forming a first silicon oxide film 68a on one surface of the first silicon substrate 60. Next, as shown in FIG.
Furthermore, by bonding the second silicon substrate 64, which is the material of the detection base material 20, using various bonding techniques such as adhesion, so as to cover the portion of the first silicon substrate 60 where the insulating part 6 is formed. , to form a laminate 66 (cavity wafer), as shown in FIG. 10(c). The second silicon substrate 64 is a conductive n-type silicon substrate. Therefore, the first silicon substrate 60 and the second silicon substrate 64 are semiconductor substrates having the same conductivity type.

By performing the layered body forming process as described above, a gap 40 surrounded by the insulating part 6 and the second silicon substrate 64 is formed at a predetermined position of the layered body 66 .
As described above, in the laminate forming step, the concave portion 62 is formed on one surface of the supporting substrate 10, the insulating portion 6 is formed on one surface of the supporting substrate 10, and the insulating portion of the supporting substrate 10 is formed. A detection substrate 20 is adhered so as to cover the portion where 6 is formed. As a result, a layered body 66 in which the gap 40 is provided between the supporting substrate 10 and the detection substrate 20 is formed.

(First electrode forming step)
In the first electrode forming step, first, as shown in FIG. 11A, a second silicon oxide film is formed on the surface of the second silicon substrate 64 opposite to the surface facing the first silicon substrate 60. 68b is deposited. The thickness of the second silicon oxide film 68b is set to 400 [nm], for example.
Next, as shown in FIG. 11B, lithography and etching techniques are used to form two first trenches 56a in the second silicon oxide film 68b. The width of the first trench 56a (the length in the horizontal direction in FIG. 11B) is set to 0.5 [mm], for example.

Further, as shown in FIG. 11(c), using the second silicon oxide film 68b as a mask, an etching technique is applied to the second silicon substrate 64 at two locations overlapping with the first trenches 56a at two locations respectively. A second trench 56b is formed.
Next, as shown in FIG. 12A, the stacked body 66 is thermally oxidized (for example, 300 [nm]) to form the first trench 56a and the second trench 56b at two locations into a third trench. It is sealed with a silicon oxide film 68c.
This prevents the second silicon substrate 64 and the first silicon substrate 60 from being short-circuited after the first electrode 54 is formed. Next, as shown in FIGS. 12(b) and 12(c), lithography and etching techniques are used to form first trenches at two locations in the second silicon oxide film 68b and the second silicon substrate 64. A portion between 56a and second trench 56b is removed. Thereby, a through hole 58 for forming the first electrode 54 is formed.

Further, as shown in FIG. 13A, the first silicon oxide film 68a formed on the first silicon substrate 60 is removed by etching. At this time, the thickness of the second silicon oxide film 68b is about 50 [nm].
Next, as shown in FIG. 13B, an n-type polysilicon 96 is deposited as an electrode material containing impurities. At this time, the inside of the through hole 58 is filled with n-type polysilicon 96 .
Further, as shown in FIG. 13(c), unnecessary n-type polysilicon 96 is removed by etching (or chemical mechanical polishing). Thereby, the first electrode 54 made of n-type polysilicon is provided inside the through hole 58 .
As described above, in the first electrode forming step, the detection base material 20 and a part of the insulating part 6 are removed, and the support base material is removed from the surface opposite to the surface of the detection base material 20 facing the support base material 10. A through hole 58 penetrating to 10 is formed. Furthermore, in the first electrode forming step, the through holes 58 are filled with an electrode material containing impurities, thereby forming the first electrodes 54 that reach from the surface of the detection substrate 20 to the support substrate 10 .

(Low resistance region forming step)
In the low-resistance region forming step, as shown in FIG. 14, ions are implanted into the first low-resistance region 72a using a photoresist pattern (not shown).
The first low-resistance region 72a is a preset region on the surface of the second silicon substrate 64 . Specifically, the first low resistance region 72a is a region where the first terminal 50 will be formed later.
After the ion implantation, the laminate 66 is subjected to heat treatment (annealing) for the purpose of ion activation and solid-phase diffusion of impurities (carriers) from the n-type polysilicon 96 to the supporting substrate 10 .

A second low-resistance region 72b (n++) is formed in a portion of the support base 10 by heat treatment.
The second low-resistance region 72 b is a preset region of the surface of the first silicon substrate 60 facing the second silicon substrate 64 . Specifically, the second low resistance region 72b is a region where the second terminal 52 will be formed later. After heat-treating the laminate 66, the second silicon oxide film 68b is removed as shown in FIG.
As described above, in the low-resistance area forming step, after ions are implanted into a preset area on the surface of the detection base material 20, the laminate 66 on which the first electrode 54 is formed is heat-treated. As a result, impurities are diffused from the first electrode 54 into the supporting substrate 10 in a solid phase to form a first low-resistance region 72 a in the ion-implanted region of the detecting substrate 20 . A second low-resistance region 72b is formed in the region.

(Wiring layer forming step)
In the wiring layer forming step, as shown in FIG. 15, a silicon nitride film 74 and a fourth silicon oxide film 68d are laminated on the upper surface of the second silicon substrate 64 in this order. Then, by normal lithography and oxide film etching, as shown in FIG. 16, the fourth silicon oxide film 68d and the silicon nitride film 74 are reached to the first low resistance region 72a and the second low resistance region 72b. A hole 76 is formed.
Next, as shown in FIG. 16, a laminated film 78 made of Ti and TiN is formed on the second silicon oxide film 68b by sputtering, and heat-treated. The laminated film 78 is a so-called barrier metal that has the role of preventing abnormal diffusion of a metal film such as Al into Si. It becomes possible to form a low-resistance connection.

Further, as shown in FIG. 17, a metal film 80 such as Al is laminated on the laminated film 78 by sputtering.
Next, by patterning the metal film 80 using photolithography and etching techniques, a wiring layer 82 as shown in FIG. 18 is formed.

After that, a photoresist pattern (not shown) is formed so as to cover areas other than the membrane setting area 84, which is a preset area including the center of the detection substrate (an area that will later become the membrane). Furthermore, the third silicon oxide film 68c and the second silicon oxide film 68b formed in the membrane setting region 84 are removed by an etching technique. Then, a photoresist pattern (not shown) is formed to cover areas other than the membrane setting area 84, and the silicon nitride film 74 in the membrane setting area 84 is removed as shown in FIG.
As described above, in the wiring layer forming step, the wiring layer 82 including the first terminal 50 electrically connected to the membrane 22 and the second terminal 52 electrically connected to the support base 10 is formed.

(Removal process)
In the removing step, a portion of the membrane setting region 84 is cut off by etching, thereby patterning four connecting portions 26a to 26d that are two pairs.
As described above, in the removing step, the membrane 22, the frame member 24, and the connecting portion 26 are removed by removing the region 72a around the preset region including the center of the detection substrate 20 and other than the first low resistance region. to form
(Receptor formation step)
In the receptor forming step, a solvent such as a PEI solution is applied to a preset region including the center of the membrane 22 to form the receptor 30 that deforms according to the adsorbed substance.

(Action/action)
The operation and action of the first embodiment will be described using FIG. 19 while referring to FIGS. 1 to 18 .
For example, when the surface stress sensor 1 is used as an olfactory sensor, the receptor 30 is placed in an atmosphere of gas containing an odor component, and the odor component contained in the gas is adsorbed on the receptor 30 as an object to be measured. .
When molecules of gas (measuring object) are adsorbed to the receptor 30 and distortion occurs in the receptor 30, surface stress is applied to the membrane 22, and the membrane 22 bends as shown in FIG.

The frame member 24 is formed in a parallel cross shape and surrounds the membrane 22, and the connecting portions 26 connect the membrane 22 and the frame member 24 at both ends. Therefore, the end portion of the connecting portion 26 that is connected to the membrane 22 is a free end, and the end portion that is connected to the frame member 24 is a fixed end.
Therefore, when the membrane 22 is flexed, the connecting portion 26 is flexed according to the strain generated in the receptor 30 . Then, the capacitance C ₀ between the membrane 22 and the connecting portion 26 and the support base 10 changes (C ₁ −C ₀ ) according to the bending of the connecting portion 26 . Then, the object to be measured is detected by reading the change in current value according to the change in capacitance (C ₁ -C ₀ ).
The first embodiment described above is an example of the present invention, and the present invention is not limited to the first embodiment described above. Various modifications are possible according to the design and the like within the scope of not departing from the technical idea.

(Effect of the first embodiment)
With the surface stress sensor 1 of the first embodiment, it is possible to obtain the effects described below.
(1) It has a conductive membrane 22 that bends due to applied surface stress, a conductive frame member 24 that surrounds the membrane 22 , and a conductive connecting portion 26 that connects the membrane 22 and the frame member 24 . Furthermore, it includes a conductive support base 10 that is connected to the frame member 24 , arranged with a gap (gap 40 ) between the membrane 22 and the connecting portion 26 , and overlaps the membrane 22 and the connecting portion 26 .

In addition to this, an insulation that electrically insulates the frame member 24 and the supporting substrate 10 from the receptor 30 that is formed on the region including the center of the surface of the membrane 22 and that causes deformation according to the adsorbed substance. A part 6 is provided. The connecting portion 26 is flexed by the deformation of the membrane 22 following the deformation of the receiving body 30, and the capacitance between the membrane 22 and the connecting portion 26 and the support substrate 10 changes due to the flexing of the connecting portion 26. .
Therefore, when the membrane 22 is flexed, the connection portion 26 is flexed in accordance with the strain generated in the receptor 30 . Then, the capacitance C ₀ between the membrane 22 and the connecting portion 26 and the support base 10 changes (C ₁ −C ₀ ) according to the bending of the connecting portion 26 . By reading the change in current value according to the change in capacitance (C ₁ -C ₀ ), it is possible to detect the object to be measured.

Also, using the change in voltage detected by a full bridge circuit formed by four resistors,
The configuration of the surface stress sensor 1 can be simplified compared to a configuration that detects changes in the resistance value of piezoresistors.
As a result, it is possible to provide the surface stress sensor 1 that can reduce current consumption and assembly cost compared to a surface sensor that detects an object to be measured by detecting changes in the resistance value of piezoresistors. Become.

(2) It further includes a first terminal 50 electrically connected to the membrane 22 and a second terminal 52 electrically connected to the support base 10 .
As a result, the capacitance between the membrane 22 and the connecting portion 26 and the supporting substrate 10, which has changed according to the bending of the connecting portion 26, is detected via the first terminal 50 and the second terminal 52. becomes possible.

(3) It further includes a capacitance change detector 100 that detects a capacitance change between the membrane 22 and the connecting portion 26 and the support base 10 .
As a result, by adding a configuration such as a computer that detects the measurement target using the change in capacitance detected by the capacitance change detection unit 100, the measurement target can be detected.

Moreover, with the inspection method of the surface stress sensor 1 of the first embodiment, it is possible to obtain the effects described below.
(4) a second voltage applying step of applying a second voltage between the first terminal 50 and the second terminal 52, and applying the second voltage between the first terminal 50 and the second terminal 52; A testing capacitance detection step is provided for detecting a testing capacitance that is the capacitance in the state. In addition to this, a state in which a first voltage different from the second voltage is applied between the capacitance during inspection detected in the capacitance detection step during inspection and the first terminal 50 and the second terminal 52 and a determination step of determining the operation of the membrane 22 based on the reference capacitance, which is the capacitance.
As a result, it is possible to detect a malfunction of the membrane 22 without requiring the fluid containing the object to be measured to adhere to the receptor 30 or the application of mechanical stress.

(5) As a pre-process of the second voltage applying process, a first voltage applying process of applying a first voltage between the first terminal 50 and the second terminal 52; and a measuring step of measuring the reference capacitance with the first voltage applied between and the second terminal 52 .
As a result, the reference capacitance used for detecting a defect in the surface stress sensor 1 can be detected without requiring adhesion of the fluid containing the measurement object to the receptor 30 or application of mechanical stress. becomes possible.

(6) Sensitivity correction, which is a sensitivity correction value corresponding to the capacitance during inspection detected in the capacitance detection step during inspection when it is determined in the determination step that the operation of the membrane 22 is better than the reference value. A correction value calculation step of calculating a value is provided. In addition to this, a correction value storage step of storing the sensitivity correction value calculated in the correction value calculation step and a sensitivity correction unit adjustment step of adjusting the sensitivity correction unit 150 using the sensitivity correction value stored in the correction value storage step are provided. .
As a result, by adjusting the sensitivity corrector 150 after the defect of the surface stress sensor 1 is detected, it is possible to improve the accuracy of detecting the object to be measured after the sensitivity corrector 150 is corrected. .

Moreover, with the method for manufacturing the surface stress sensor of the first embodiment, it is possible to obtain the effects described below.
(7) A laminate forming step, a first electrode forming step, a low resistance region forming step, a removing step, and a wiring layer forming step.
The laminate forming step is a step of forming the recesses 62 on one surface of the supporting base material 10 and forming the insulating portion 6 on one surface. Furthermore, in the laminate forming step, the detection base material 20 is attached so as to cover the part of the support base material 10 where the insulating part 6 is formed. 40 is a step of forming a laminate 66 provided with . In the first electrode forming step, a part of the detection base material 20 and the insulating part 6 is removed, and the surface of the detection base material 20 opposite to the surface facing the support base material 10 penetrates to the support base material 10. This is a step of forming a through-hole 58 to be formed. Furthermore, the first electrode forming step is a step of forming the first electrode 54 reaching the support base 10 from the surface by embedding the through hole 58 with an electrode material containing impurities. In the low-resistance area forming step, after implanting ions into a preset area on the surface of the detection base material 20, the laminate 66 having the first electrode 54 formed thereon is heat-treated so that the first electrode 54 is removed from the support base material. 10 to form a first low-resistance region 72a in the ion-implanted region of the detection substrate 20 and a second low-resistance region 72b in a portion of the support substrate 10. It is a process to do. In the removing step, the membrane 22, the frame member 24, and at least the pair of connecting portions 26 are removed by removing a region around a preset region including the center of the detection substrate 20 and other than the first low resistance region 72a. It is a step of forming The wiring layer forming step is a step of forming the wiring layer 82 including the first terminal 50 electrically connected to the membrane 22 and the second terminal 52 electrically connected to the support base 10 .

Therefore, when the membrane 22 is flexed, the connection portion 26 is flexed in accordance with the strain generated in the receptor 30 . Then, the capacitance C ₀ between the membrane 22 and the connecting portion 26 and the support base 10 changes (C ₁ −C ₀ ) according to the bending of the connecting portion 26 . By reading the change in current value according to the change in capacitance (C ₁ -C ₀ ), it is possible to detect the object to be measured.
In addition, the surface stress sensor 1 can be manufactured with a simplified configuration compared to a configuration that detects a change in the resistance value of a piezoresistor using a change in voltage detected by a full bridge circuit formed of four resistors. becomes possible.
As a result, it is intended to provide a method of manufacturing a surface stress sensor that can reduce current consumption and assembly costs compared to a surface sensor that detects an object to be measured by detecting changes in the resistance value of piezoresistors. becomes possible.

(Modification of first embodiment)
(1) In the first embodiment, n-type silicon, which is a conductive material, was used as the material forming the supporting substrate 10 and the detecting substrate 20. However, the supporting substrate 10 and the detecting substrate 20 are formed by Materials are not limited to these.
That is, for example, as shown in FIG. 20, by laminating a conductor layer 160 formed of a conductive material on a base layer 150 formed of a semiconductor base material or an insulating base material, the support base 10 and the detection A substrate 20 may be formed.
In the case of manufacturing the surface stress sensor 1 having the configuration shown in FIG. 160 is formed. After that, the substrate layer 150 forming the supporting substrate 10 and the substrate layer 150 forming the detection substrate 20 are bonded together.

Therefore, at least one of the membrane 22, the frame member 24, the connecting part 26, and the supporting substrate 10 may be formed of a laminated substrate formed by laminating a conductor on a semiconductor substrate or an insulating substrate. .
In this case, the choice of materials for forming the supporting substrate 10 and the detecting substrate 20 is increased, so that the application target of the surface stress sensor 1 can be expanded.

(2) In the first embodiment, a portion of the insulating portion 6 surrounds the second terminal 52, and the portion of the insulating portion 6 other than the portion surrounding the second terminal 52 is the support base 10 and the frame member 24. Although it is configured to be arranged between and, it is not limited to this.
That is, for example, as shown in FIGS. 21 and 22, the frame member 24 has a penetrating portion 24a penetrating from the surface opposite to the surface facing the supporting substrate 10 to the surface facing the supporting substrate 10. may be
With this configuration, a portion of the insulating portion 6 is exposed from a portion of the frame member 24 when viewed from the thickness direction of the membrane 22, thereby reducing the area of the frame member 24 facing the support base 10. It is possible to

By the way, in the configuration of the first embodiment, the electrostatic capacitance between the membrane 22 and the connecting portion 26 and the supporting substrate 10 and the electrostatic capacitance between the frame member 24 and the supporting substrate 10 are connected in parallel. exists in the The dielectric constant of the insulating portion 6 is greater than the dielectric constant of the void portion 40 , and the distance between the frame member 24 and the supporting base material 10 is smaller than the distance between the membrane 22 and the supporting base material 10 . Furthermore, the frame member 24 does not deform when the object to be measured is detected. Therefore, the capacitance of the frame member 24 of the detection substrate 20 is larger than the capacitance of the membrane 22 of the detection substrate 20, and the capacitance between the frame member 24 and the support substrate 10 is , causing the offset.
On the other hand, with the configuration shown in FIGS. 21 and 22, the area of the frame member 24 facing the supporting base material 10 can be reduced. It becomes possible to reduce the offset with respect to the capacitance.

(3) In the first embodiment, a portion of the insulating portion 6 surrounds the second terminal 52, and the portion of the insulating portion 6 other than the portion surrounding the second terminal 52 is the support base 10 and the frame member 24. Although it is configured to be arranged between and, it is not limited to this.
That is, for example, as shown in FIGS. 23 and 24, the penetrating portion 24a, except for the portion between the first terminal 50 and the membrane 22, the inside 24b of the frame member 24, the membrane 22 and the connecting portion 26, and the frame It is good also as the structure formed between the outer side 24c of the member 24. FIG.
With this configuration, compared with the configurations shown in FIGS. It is possible to further reduce the offset with respect to the capacitance between

(4) In the first embodiment, n-type silicon, which is a conductive material, was used as the material forming the support substrate 10 and the detection substrate 20. However, the support substrate 10 and the detection substrate 20 are formed by Materials are not limited to these.
That is, p-type silicon, which is a conductive material, may be used as the material forming the support base 10 and the detection base 20 . Alternatively, n-type silicon may be used as the material forming the support base 10 and p-type silicon may be used as the material forming the detection base 20 . Similarly, p-type silicon may be used as the material forming the support substrate 10 and n-type silicon may be used as the material forming the detection substrate 20 .

(5) In the first embodiment, the gap 40 is formed between the membrane 22 and the support base 10 by forming the concave portion 62 on one surface of the first silicon substrate 60 that is the material of the support base 10 . formed, but not limited to. That is, by forming recesses in the surface of the second silicon substrate 64, which is the material of the detection substrate 20, facing the support substrate 10, the gap 40 is formed between the membrane 22 and the support substrate 10. good too.

(6) In the first embodiment, the area of the connection portion 4 is smaller than the area of the membrane 22 when viewed from the thickness direction of the membrane 22. However, the area of the connection portion 4 is not limited to this. The area may be equal to or greater than the area of the membrane 22 .
(7) In the first embodiment, the shape of the connection portion 4 is circular, but the shape is not limited to this, and the shape of the connection portion 4 may be square, for example. Also, a plurality of connecting portions 4 may be formed.

(8) In the first embodiment, the material forming the detection substrate 20 and the material forming the support substrate 10 were the same material, but the present invention is not limited to this. The forming material and the material forming the supporting substrate 10 may be different materials.
In this case, by setting the difference between the linear expansion coefficient of the detection substrate 20 and the linear expansion coefficient of the support substrate 10 to 1.2×10 ⁻⁵ /° C. or less, the detection can be performed according to the deformation of the package substrate 2 . It is possible to reduce the difference between the amount of deformation of the base material 20 and the amount of deformation of the supporting base material 10 . This makes it possible to suppress the bending of the membrane 22 .

(9) In the first embodiment, the coefficient of linear expansion of the supporting substrate 10 was set to 5.0×10 ⁻⁶ /° C. or less, but the linear expansion coefficient of the supporting substrate 10 is not limited to this. , 1.0×10 ⁻⁵ /° C. or less.
Even in this case, it is possible to improve the rigidity of the support base 10 and reduce the amount of deformation of the detection base 20 with respect to deformation of the package substrate 2 caused by temperature changes or the like.

(10) In the first embodiment, the inspection method of the surface stress sensor 1 includes a second voltage application step, an inspection capacitance detection step, a judgment step, a first voltage application step, and a measurement step. However, it is not limited to this. That is, if the reference capacitance is known, the inspection method for the surface stress sensor 1 may be configured without the first voltage applying step and the measuring step. In this case, in the determination step, the first voltage is set to 0 [V], and the second voltage is set to a value according to the configuration of the surface stress sensor 1 .

(11) In the first embodiment, in the first electrode forming step, by filling the through holes 58 with an electrode material containing impurities, the first electrode 54 reaching from the surface of the detection substrate 20 to the support substrate 10 was formed, but is not limited to this.
That is, in the first electrode forming step, for example, after filling the through holes 58 with an electrode material that does not contain impurities (non-doped polysilicon or the like), impurities are injected into the electrode material in the through holes 58 to form the first electrode. An electrode 54 may be formed.

(Second embodiment)
A second embodiment of the present invention will be described below with reference to the drawings.
(Constitution)
The configuration of the second embodiment will be described using FIG. 25 while referring to FIGS. 1 to 10 .
In the configuration of the second embodiment, as shown in FIG. 25, the frame member 24 is provided on the surface of the support base 10 opposite to the surface facing the package substrate 2 via the connection layer 90 (in FIG. 25, It is the same as the first embodiment described above, except that it is connected to the upper surface).
The connection layer 90 is formed using silicon dioxide (SiO ₂ ) or the like.
Since other configurations are the same as those of the above-described first embodiment, description thereof is omitted.

(Manufacturing method of surface stress sensor)
A method of manufacturing the surface stress sensor 1 will be described using FIGS. 26 to 34 while referring to FIGS. 1 to 24. FIG. The cross-sectional views of FIGS. 26 to 34 correspond to the cross-sectional view taken along line XX of FIG.
A method for manufacturing the surface stress sensor 1 includes a laminate forming step, a first electrode forming step, a low resistance region forming step, a hole forming step, a gap portion forming step, a hole sealing step, a removing step, A wiring layer forming step is provided.

(Laminate forming step)
In the laminated body forming step, first, as shown in FIG. 26, an insulating sacrificial layer 92 formed using a silicon oxide film is laminated on the first silicon substrate 60 which is the material of the support base 10 . Furthermore, the second silicon substrate 64 that will be the material of the detection substrate 20 is laminated on the sacrificial layer 92 . As the sacrificial layer 92, in addition to the silicon oxide film, a silicon nitride film or a metal film such as aluminum, titanium, copper, or tungsten may be used.
As described above, in the laminate forming step, the insulating sacrificial layer 92 is laminated on the supporting substrate 10 , and the detection substrate 20 is further laminated on the insulating sacrificial layer 92 to form the laminate 66 .

(First electrode forming step)
In the first electrode forming step, first, as shown in FIG. 27A, a second silicon oxide film is formed on the surface of the second silicon substrate 64 opposite to the surface facing the first silicon substrate 60. 68b is deposited.
Next, as shown in FIG. 27B, lithography and etching techniques are used to form two first trenches 56a in the second silicon oxide film 68b. The width of the first trench 56a (the length in the horizontal direction in FIG. 27B) is set to 0.5 [mm], for example.

Further, as shown in FIG. 27(c), using the second silicon oxide film 68b as a mask, an etching technique is applied to the second silicon substrate 64 at two locations overlapping with the first trenches 56a at two locations respectively. A second trench 56b is formed.
Next, as shown in FIG. 28A, the stacked body 66 is thermally oxidized (for example, 300 [nm]) to form the first trench 56a and the second trench 56b at two locations into a third trench. It is sealed with a silicon oxide film 68c.
This prevents the second silicon substrate 64 and the first silicon substrate 60 from being short-circuited after the first electrode 54 is formed. Next, as shown in FIGS. 28(b) and 28(c), lithography and etching techniques are used to form first trenches at two locations in the second silicon oxide film 68b and the second silicon substrate 64. A portion between 56a and second trench 56b is removed. Thereby, a through hole 58 for forming the first electrode 54 is formed.

Furthermore, as shown in FIG. 29A, the portion of the sacrificial layer 92 formed on the first silicon substrate 60 that is continuous with the through hole 58 and the first silicon layer formed on the second silicon substrate 64 The oxide film 68a is removed by etching. At this time, the thickness of the first silicon oxide film 68a is about 50 [nm].
Next, as shown in FIG. 29B, an n-type polysilicon 96 is deposited as an electrode material containing impurities. At this time, the inside of the through hole 58 is filled with n-type polysilicon 96 .
Further, as shown in FIG. 29(c), unnecessary n-type polysilicon 96 is removed by etching (or chemical mechanical polishing). Thereby, the first electrode 54 made of n-type polysilicon is provided inside the through hole 58 .

As described above, in the first electrode forming step, the detection base material 20 and a part of the insulating part 6 are removed, and the support base material is removed from the surface opposite to the surface of the detection base material 20 facing the support base material 10. A through hole 58 penetrating to 10 is formed. Furthermore, in the first electrode forming step, the through holes 58 are filled with an electrode material containing impurities, thereby forming the first electrodes 54 that reach from the surface of the detection substrate 20 to the support substrate 10 .

(Low resistance region forming step)
In the low-resistance region forming step, as shown in FIG. 30, ions are implanted into the first low-resistance region 72a using a photoresist pattern (not shown).
The first low-resistance region 72a is a preset region on the surface of the second silicon substrate 64 . Specifically, the first low resistance region 72a is a region where the first terminal 50 will be formed later.
Thereafter, the laminate 66 is subjected to a heat treatment (annealing treatment) for the purpose of ion activation and solid-phase diffusion of impurities (carriers) from the n-type polysilicon 96 to the supporting substrate 10 .

A second low-resistance region 72b (n++) is formed in a portion of the support base 10 by heat treatment.
The second low-resistance region 72 b is a preset region of the surface of the first silicon substrate 60 facing the second silicon substrate 64 . Specifically, the second low resistance region 72b is a region where the second terminal 52 will be formed later.
As described above, in the low-resistance area forming step, after ions are implanted into a preset area on the surface of the detection base material 20, the laminate 66 on which the first electrode 54 is formed is heat-treated. As a result, impurities are diffused from the first electrode 54 into the supporting substrate 10 in a solid phase to form a first low-resistance region 72 a in the ion-implanted region of the detecting substrate 20 . A second low-resistance region 72b is formed in the region.

(Hole forming process)
In the hole forming step, a hole pattern (not shown) is formed on the upper surface of the second silicon substrate 64 by a general photolithographic technique.
Next, dry etching is performed using the hole pattern as a mask to form holes 76 in the second silicon substrate 64 as shown in FIG. The diameter of the hole 76 is set to 0.28 [μm], for example, and the depth is set to reach the sacrificial layer 92 .
As described above, in the hole forming step, the hole 76 penetrating to the sacrificial layer 92 is formed in a preset region of the detection substrate 20 including the center of the detection substrate 20 .

(Gap forming step)
In the gap forming step, HF Vapor is allowed to permeate the first silicon substrate 60 side through the holes 76 to selectively etch only the sacrificial layer 92. As shown in FIG. A gap 40 is formed between the two silicon substrates 64 . After forming the void 40, as shown in FIG. 32, the second silicon oxide film 68b formed on the upper surface of the second silicon substrate 64 is removed.
Here, the reason why HF wet etching is not used is to avoid the occurrence of a problem (also called stiction) in which the gap 40 is crushed by the surface tension of pure water or the like during drying after forming the gap 40. It's for.

Further, in the gap forming step, by forming the gap 40 between the first silicon substrate 60 and the second silicon substrate 64, the gap between the first silicon substrate 60 and the second silicon substrate 64 is sacrificial. An insulating portion 6 is formed at the position where the layer 92 is left.
The insulating portion 6 electrically insulates the first silicon substrate 60 and the second silicon substrate 64 .

As described above, in the gap forming step, etching through the hole 76 removes the sacrificial layer 92 disposed between the support substrate 10 and a predetermined region including the center of the detection substrate 20 to remove the supporting substrate. A gap 40 is provided between the substrate 10 and the detection substrate 20 . In addition to this, in the gap forming step, between the detection substrate 20 and the support substrate 10, a sacrificial layer 92 is provided at a position where the sacrificial layer 92 remains, and the detection substrate 20 and the support substrate 10 are electrically connected. Insulating portion 6 is formed to insulate from .

(Hole sealing process)
In the hole sealing step, the hole 76 is sealed with an oxide film 94, as shown in FIG.
As a method for sealing the hole 76, for example, it is effective to combine thermal oxidation treatment and CVD, but if the diameter of the hole 76 is small, it is also possible to use only CVD.
As described above, in the hole sealing step, the hole 76 is sealed by forming the oxide film 94 on the surface of the detecting substrate 20 opposite to the surface facing the supporting substrate 10 .

(Wiring layer forming step)
Since the wiring layer forming process is performed in the same procedure as in the above-described first embodiment, the description thereof is omitted.
As described above, in the wiring layer forming step, as shown in FIG. A layer 82 is formed.

(Removal process)
Since the removal step is performed in the same procedure as in the above-described first embodiment, the explanation thereof will be omitted.
(Receptor formation step)
Since the receptor forming step is performed in the same procedure as in the above-described first embodiment, the explanation thereof is omitted.

(Action/action)
The operation and effects of the second embodiment are the same as those of the above-described first embodiment, so description thereof will be omitted.
In addition, the second embodiment described above is an example of the present invention, and the present invention is not limited to the second embodiment described above. Various modifications are possible according to the design and the like within the scope of not departing from the technical idea.

(Effect of Second Embodiment)
With the method for manufacturing the surface stress sensor of the second embodiment, it is possible to obtain the effects described below.
(1) A laminate forming step, a first electrode forming step, a low resistance region forming step, a hole forming step, a gap portion forming step, a hole sealing step, a removing step, and a wiring layer forming step. . The laminate formation step is a step of laminating an insulating sacrificial layer 92 on the supporting substrate 10 and then laminating the detection substrate 20 on the sacrificial layer 92 to form the laminate 66 . In the first electrode forming step, a part of the detection substrate 20 is removed to form a through hole 58 penetrating from the surface of the detection substrate 20 opposite to the surface facing the support substrate 10 to the support substrate 10. It is a step of forming Furthermore, the first electrode forming step is a step of forming the first electrode 54 reaching the support base 10 from the surface by embedding the through hole 58 with an electrode material containing impurities. In the low-resistance area forming step, after implanting ions into a preset area on the surface of the detection base material 20, the laminate 66 having the first electrode 54 formed thereon is heat-treated so that the first electrode 54 is removed from the support base material. 10 to form a first low-resistance region 72a in the ion-implanted region of the detection substrate 20 and a second low-resistance region 72b in a portion of the support substrate 10. It is a process to do. The hole forming step is a step of forming a hole 76 penetrating to the sacrificial layer 92 in a preset region of the detection substrate 20 including the center of the detection substrate 20 . The gap forming step removes the sacrificial layer 92 disposed between a predetermined region including the center of the detection substrate 20 and the support substrate 10 by etching through a hole, thereby removing the support substrate 10 and detection. This is the step of providing the gap 40 between the substrate 20 and the base material 20 . In addition to this, the gap forming step is provided at a position between the detection substrate 20 and the support substrate 10 where the sacrificial layer 92 remains, and the detection substrate 20 and the support substrate 10 are electrically connected. This is a step of forming an insulating portion 6 that insulates the . The hole sealing step is a step of sealing the holes 76 by forming an oxide film on the surface of the detection substrate 20 opposite to the surface facing the support substrate 10 . In the removing step, the membrane 22, the frame member 24, and at least the pair of connecting portions 26 are removed by removing a region around a preset region including the center of the detection substrate 20 and other than the first low resistance region 72a. It is a step of forming The wiring layer forming step is a step of forming the wiring layer 82 including the first terminal 50 electrically connected to the membrane 22 and the second terminal 52 electrically connected to the support base 10 .

Therefore, when the membrane 22 is flexed, the connection portion 26 is flexed in accordance with the strain generated in the receptor 30 . Then, the capacitance C ₀ between the membrane 22 and the connecting portion 26 and the support base 10 changes (C ₁ −C ₀ ) according to the bending of the connecting portion 26 . By reading the change in current value according to the change in capacitance (C ₁ -C ₀ ), it is possible to detect the object to be measured.
In addition, the surface stress sensor 1 can be manufactured with a simplified configuration compared to a configuration that detects a change in the resistance value of a piezoresistor using a change in voltage detected by a full bridge circuit formed of four resistors. becomes possible.
As a result, it is intended to provide a method of manufacturing a surface stress sensor that can reduce current consumption and assembly costs compared to a surface sensor that detects an object to be measured by detecting changes in the resistance value of piezoresistors. becomes possible.

DESCRIPTION OF SYMBOLS 1... Surface stress sensor 2... Package substrate 4... Connection part 6... Insulating part 10... Support base material 20... Detection base material 22... Membrane 24... Frame member 24a... Through part 24b... Frame Inner side of member 24 24c Outer side of frame member 24 26 Connecting portion 30 Receptor 31 Receptor-forming region 40 Gap 50 First terminal 52 Second terminal 54 Second One electrode 56a First trench 56b Second trench 58 Through hole 60 First silicon substrate 62 Recess 64 Second silicon substrate 66 Laminated body 68 Silicon oxide film , 72... Low resistance region 74... Silicon nitride film 76... Hole 78... Laminated film 80... Metal film 82... Wiring layer 84... Membrane setting area 88... Photoresist 90... Connection layer 92... Sacrificial layer 94 Oxide film 96 N-type polysilicon 100 Capacitance change detector 110 Power supply 120 Current detection circuit 120a Operational amplifier 120b Resistor 120c Capacitor 120d Multiplier 120e 120 f A/D converter 130 storage unit 140 difference calculation unit 150 base material layer 160 conductor layer 170 sensitivity correction unit VL1 virtual virtual passing through the center of the membrane Straight line, VL2... Straight line perpendicular to straight line VL1

Claims (10)

a conductive membrane that flexes with applied surface stress;
a conductive frame member that is spaced apart from the membrane when viewed in the thickness direction of the membrane and surrounds the membrane;
at least a pair of conductive connecting portions arranged at at least two positions sandwiching the membrane when viewed in the thickness direction and connecting the membrane and the frame member;
a conductive support base that is connected to the frame member, is arranged with a gap between the membrane and the connecting portion, and overlaps the membrane and the connecting portion when viewed from the thickness direction;
a receptor formed on a region including the center of the surface of the membrane opposite to the surface facing the supporting substrate and deforming according to the adsorbed substance;
an insulating portion provided between the frame member and the supporting base material for electrically insulating the frame member and the supporting base material;
the connecting portion is bent by deformation of the membrane following deformation of the receptor;
A surface stress sensor in which the electrostatic capacitance between the membrane and the connection portion and the supporting base material changes according to the bending of the connection portion. 2. At least one of the membrane, the frame member, the connection part and the supporting base material is formed of a laminated base material formed by laminating a conductor on a semiconductor base material or an insulating base material. A surface stress sensor as described in . 3. The surface stress sensor according to claim 1, further comprising a capacitance change detector that detects a change in the capacitance. 4. The surface according to any one of claims 1 to 3, wherein the frame member includes a penetrating portion penetrating from the surface opposite to the surface facing the supporting base material to the surface facing the supporting base material. stress sensor. further comprising a first terminal electrically connected to the membrane,
5. The through portion is formed between the inner side of the frame member, the membrane and the connecting portion, and the outer side of the frame member, except for the portion between the first terminal and the membrane. A surface stress sensor as described in . 6. A surface as claimed in any preceding claim, further comprising a first terminal electrically connected to the membrane and a second terminal electrically connected to the support substrate. stress sensor. An inspection method for inspecting the operation of the membrane for the surface stress sensor according to claim 6,
a second voltage applying step of applying a second voltage between the first terminal and the second terminal;
a testing capacitance detection step of detecting a testing capacitance that is the capacitance in a state where the second voltage is applied between the first terminal and the second terminal;
The static capacitance in a state in which a first voltage different from the second voltage is applied between the testing capacitance detected in the testing capacitance detection step and the first terminal and the second terminal and a determination step of determining the operation of the membrane based on a reference capacitance that is a capacitance. As a step preceding the second voltage applying step, a first voltage applying step of applying the first voltage between the first terminal and the second terminal; 8. The method of inspecting a surface stress sensor according to claim 7, further comprising a measuring step of measuring the reference capacitance while the first voltage is applied between and the second terminal. Forming a concave portion on one surface of a supporting substrate, forming an insulating portion on the one surface, and bonding a detection substrate so as to cover a portion of the supporting substrate on which the insulating portion is formed. A layered body forming step of forming a layered body in which a gap is provided between the supporting substrate and the detecting substrate;
removing a part of the detection substrate and the insulating portion to form a through hole penetrating from the surface of the detection substrate opposite to the surface facing the support substrate to the support substrate; a first electrode forming step of forming a first electrode reaching from the surface to the supporting substrate by filling the through hole with an electrode material containing impurities;
By implanting ions into a predetermined region of the surface of the detection base material and heat-treating the laminate on which the first electrode is formed, the impurity is solidified from the first electrode to the support base material. diffusion to form a first low-resistance region in the ion-implanted region of the detection substrate, and a second low-resistance region in a preset region of the surface of the support substrate facing the detection substrate. a low resistance region forming step of forming a low resistance region;
By removing a region other than the first low resistance region around a preset region including the center of the detection substrate, the membrane is bent by the applied surface stress, from the thickness direction of the membrane Forming a frame member surrounding the membrane with a gap when viewed, and at least a pair of connecting portions arranged at at least two positions sandwiching the membrane when viewed in the thickness direction and connecting the membrane and the frame member. a removal step to
A method of manufacturing a surface stress sensor, comprising a wiring layer forming step of forming a wiring layer including first terminals electrically connected to the membrane and second terminals electrically connected to the supporting base. . a laminate forming step of laminating an insulating sacrificial layer on a supporting substrate and further laminating a detection substrate on the sacrificial layer to form a laminate;
removing a part of the detection substrate to form a through-hole penetrating from the surface of the detection substrate opposite to the surface facing the support substrate to the support substrate; a first electrode forming step of forming a first electrode reaching from the surface to the supporting substrate by filling the through holes with an electrode material contained;
By implanting ions into a predetermined region of the surface of the detection base material and heat-treating the laminate on which the first electrode is formed, the impurity is solidified from the first electrode to the support base material. diffusion to form a first low-resistance region in the ion-implanted region of the detection substrate, and a second low-resistance region in a preset region of the surface of the support substrate facing the detection substrate. a low resistance region forming step of forming a low resistance region;
a hole forming step of forming a hole penetrating to the sacrificial layer in a predetermined region including the center of the detection substrate of the detection substrate;
Etching through the hole removes the sacrificial layer disposed between the support substrate and a preset region including the center of the detection substrate, thereby removing the sacrificial layer between the support substrate and the detection substrate. An insulation that is provided between the detection base material and the support base material at a position where the sacrificial layer remains, and that electrically insulates the detection base material from the support base material. A gap forming step for forming a part;
a hole sealing step of forming an oxide film on the surface of the detection substrate opposite to the surface facing the support substrate to seal the hole;
By removing a region other than the first low resistance region around a preset region including the center of the detection substrate, the membrane is bent by the applied surface stress, from the thickness direction of the membrane Forming a frame member surrounding the membrane with a gap when viewed, and at least a pair of connecting portions arranged at at least two positions sandwiching the membrane when viewed in the thickness direction and connecting the membrane and the frame member. a removal step to
A method of manufacturing a surface stress sensor, comprising a wiring layer forming step of forming a wiring layer including first terminals electrically connected to the membrane and second terminals electrically connected to the supporting base. .

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