Pressure measuring device

Abstract

The present invention relates to a pressure measuring device capable of suppressing the increase of processed signals and performing fault diagnosis of the pressure measuring device. The present invention comprises a first resistor element (103a), a second resistor element (103b), a third resistor element (103c), and a fourth resistor element (103d) arranged in a pressure receiving area (102), which form a first bridge circuit, and a first connection pad (105a) connecting the first bridge circuit to a power source (106) and to a wiring (107) at the other end of a temperature measuring element (104) passing through the pressure receiving area (102).

Description

Technical Field

[0001] The invention relates to a pressure measuring device. Background Art

[0002] For example, in petroleum, petrochemical, chemical equipment, etc., a pressure measuring device is used in which a piezoresistance element is provided in a pressure-bearing area of ​​a diaphragm in order to measure the flow rate, pressure, liquid level, specific gravity, etc. of a process fluid (see Patent Document 1). In such a pressure measuring device, a temperature measuring element is used in order to perform temperature correction of the pressure sensor.

[0003] In addition, in such a pressure measuring device, it is very important to detect the state of diaphragm damage as a fault diagnosis. For example, there is a technology for detecting diaphragm damage based on the potential difference between the midpoint potential of a bridge circuit formed by four piezoresistors provided on the diaphragm and a reference potential generating circuit provided outside the diaphragm (see Patent Document 2). In this technology, the potential difference V at the two midpoints B and C of the bridge circuit is BC , the potential difference V between the potential at the midpoint B and the reference potential of the reference potential generating circuit CE , and the potential difference V between the potential at the midpoint C and the reference potential of the reference potential generating circuit BE Make a comparison.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Laid-Open No. 09-329516

[0007] Patent Document 2: Japanese Patent Application Publication No. 2001-272293 Summary of the invention

[0008] Problem that the invention aims to solve

[0009] However, in the above fault diagnosis, the potential difference V BC , potential difference V CE and the potential difference V BE These three potential differences have the problem of processing too many signals.

[0010] The present invention has been made to solve the above-mentioned problem, and an object of the present invention is to enable fault diagnosis of a pressure measuring device while suppressing an increase in processing signals.

[0011] Technical means of solving problems

[0012] The pressure measuring device of the present invention comprises: a diaphragm layer; a pressure-bearing area formed in the diaphragm layer; a first bridge circuit composed of one or more resistor elements arranged in the diaphragm layer and measuring the strain of the pressure-bearing area through the piezoresistance effect; a temperature measuring element arranged in the diaphragm layer; a second bridge circuit including a temperature measuring element, at least a part of the wiring is arranged on the pressure-bearing area, and outputs the temperature measured by the temperature measuring element; and a determination unit, which is configured to determine a fault in the pressure-bearing area based on the output of the second bridge circuit.

[0013] In one configuration example of the above-mentioned pressure measuring device of technical solution 1, it is provided with: a first connecting pad, which is formed on the diaphragm layer outside the pressure area and connected to the second bridge circuit and the power supply; a second connecting pad, which is formed on the diaphragm layer outside the pressure area and connected to one end of the temperature measuring element; and a wiring, which is formed on the diaphragm layer and connects the first connecting pad and the second connecting pad via the temperature measuring element and through the pressure area.

[0014] In one configuration example of the above-mentioned pressure measuring device, it is provided with: a first connecting pad, which is formed on the diaphragm layer outside the pressure area and connected to the second bridge circuit and the ground wire; a second connecting pad, which is formed on the diaphragm layer outside the pressure area and connected to one end of the temperature measuring element; and a wiring, which is formed on the diaphragm layer, connecting the first connecting pad and the second connecting pad via the temperature measuring element and through the pressure area.

[0015] In one configuration example of the pressure measuring device, the diaphragm layer is made of n-type single crystal silicon whose main surface is set to a (100) plane, and the wiring is <100> A p-type semiconductor diffusion resistor is formed by extending in the direction.

[0016] The pressure measuring device of the present invention comprises: a diaphragm layer; a first pressure-bearing area and a second pressure-bearing area, which are formed in the diaphragm layer; a first bridge circuit, which is composed of one or more resistor elements arranged in the diaphragm layer and which measure the strain of the first pressure-bearing area by the piezoresistance effect; a temperature measuring element arranged in the diaphragm layer; a second bridge circuit, which includes the temperature measuring element, at least a part of the wiring is arranged on the first pressure-bearing area and the second pressure-bearing area, and outputs the temperature measured by the temperature measuring element; a third bridge circuit, which is composed of one or more resistor elements arranged in the diaphragm layer and which measure the strain of the second pressure-bearing area by the piezoresistance effect; and a determination unit, which is configured to determine the fault of the first pressure-bearing area and the second pressure-bearing area based on the output of the second bridge circuit.

[0017] In one configuration example of the above-mentioned pressure measuring device, it is provided with: a first connecting pad, which is formed on the diaphragm layer outside the first pressure area and the second pressure area, connecting the second bridge circuit and the power supply; a second connecting pad, which is formed on the diaphragm layer outside the first pressure area and the second pressure area, and connected to one end of the temperature measuring element; and a wiring, which is formed on the diaphragm layer, connecting the first connecting pad and the second connecting pad via the temperature measuring element and through the first pressure area and the second pressure area.

[0018] In one configuration example of the above-mentioned pressure measuring device, it is provided with: a first connecting pad, which is formed on the diaphragm layer outside the first pressure area and the second pressure area, connecting the second bridge circuit and the ground wire; a second connecting pad, which is formed on the diaphragm layer outside the first pressure area and the second pressure area, and connected to one end of the temperature measuring element; and a wiring, which is formed on the diaphragm layer, connecting the first connecting pad and the second connecting pad via the temperature measuring element and through the first pressure area and the second pressure area.

[0019] In one configuration example of the pressure measuring device, the diaphragm layer is made of n-type single crystal silicon whose main surface is set to a (100) plane, and the wiring is <100> A p-type semiconductor diffusion resistor is formed by extending in the direction.

[0020] Effects of the Invention

[0021] As described above, according to the present invention, by passing the wiring connected to the temperature measuring element over the pressure receiving region, it is possible to perform a fault diagnosis of the pressure measuring device without adding a new signal to be processed. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1A It is a plan view showing the structure of the pressure measuring device according to the first embodiment of the present invention.

[0023] Figure 1B It is a cross-sectional view showing the structure of the pressure measuring device according to the first embodiment of the present invention.

[0024] Figure 2 It is a plan view showing a partial configuration of another pressure measuring device according to the first embodiment of the present invention.

[0025] Figure 3 It is a plan view showing a partial configuration of another pressure measuring device according to the first embodiment of the present invention.

[0026] Figure 4 It is a plan view showing a partial configuration of another pressure measuring device according to the first embodiment of the present invention.

[0027] Figure 5It is a plan view showing a partial configuration of another pressure measuring device according to Embodiment 2 of the present invention.

[0028] Figure 6 It is a plan view showing a partial configuration of another pressure measuring device according to Embodiment 2 of the present invention.

[0029] Figure 7 It is a plan view showing a partial configuration of another pressure measuring device according to Embodiment 2 of the present invention.

[0030] Figure 8 It is a plan view showing a partial configuration of another pressure measuring device according to Embodiment 2 of the present invention. DETAILED DESCRIPTION

[0031] Hereinafter, a pressure measuring device according to an embodiment of the present invention will be described.

[0032] [Implementation Method 1]

[0033] First, refer to Figure 1A , Figure 1B A pressure measuring device according to a first embodiment of the present invention will be described. The pressure measuring device includes a pressure sensor including a diaphragm layer 101, a pressure calculating unit 108, and a determining unit 109. The diaphragm layer 101 may be composed of, for example, n-type single crystal silicon whose main surface is a (100) plane. The diaphragm layer 101 is formed, for example, on a substrate 111. A through hole 112 is formed in the substrate 111, penetrating the substrate 111 in the thickness direction. The substrate 111 may be composed of, for example, n-type single crystal silicon whose main surface is a (100) plane.

[0034] A pressure-receiving region 102 is formed on the diaphragm layer 101 . The pressure-receiving region 102 is, for example, circular in plan view. The pressure-receiving region 102 is a region of a portion of the diaphragm layer 101 defined by the space of the through hole 112 formed in the base 111 .

[0035] Four resistors, namely, the first resistor 103a, the second resistor 103b, the third resistor 103c and the fourth resistor 103d, are provided on the diaphragm layer 101 at the periphery of the pressure-bearing region 102 to measure the strain of the pressure-bearing region 102 by the piezoresistance effect. These resistors are arranged at the location where the piezoelectric effect is generated in the pressure-bearing region 102. For example, the resistors can be composed of a p-type region, which is a predetermined location of the diaphragm layer 101 composed of n-type single crystal silicon with the main surface set to the (100) plane, for example, with a 10 18 (atoms / cm 3 ) is introduced as a p-type impurity (B) at a concentration of about ).

[0036] Each resistor element is rectangular in shape when viewed from above, and the length direction of the rectangle is in the direction of the silicon single crystal. <110> The first bridge circuit is composed of a first resistor element 103a, a second resistor element 103b, a third resistor element 103c, and a fourth resistor element 103d. However, the first bridge circuit may be composed of one or more resistor elements that measure the strain of the pressure-bearing region 102 by the piezo-resistance effect. In addition, the number of resistor elements constituting the first bridge circuit is not limited to four.

[0037] In addition, a temperature measuring element 104 is provided on the diaphragm layer 101. The temperature measuring element 104 can be arranged, for example, on the diaphragm layer 101 outside the pressure receiving region 102. The temperature measuring element 104 can be composed of a p-type region, which is a predetermined portion of the diaphragm layer 101 composed of n-type single crystal silicon whose main surface is set to a (100) plane, for example, 18 (atoms / cm 3 ) is formed by introducing B as a p-type impurity at a concentration of about ).

[0038] In addition, a first connection pad 105a connecting the above-mentioned bridge circuit and the power supply 106, and a second connection pad 105b connected to one end of the temperature measuring element 104 are formed on the diaphragm layer 101 outside the pressure-bearing region 102. In addition, a wiring 107 connecting the first connection pad 105a and the other end of the temperature measuring element 104 is formed on the diaphragm layer 101 through the pressure-bearing region 102 (through the pressure-bearing region 102). The wiring 107 is formed on the diaphragm layer 101, and connects the first connection pad 105a and the second connection pad 105b via the temperature measuring element 104 and through the pressure-bearing region 102. In addition, a second bridge circuit is formed by the temperature measuring element 104 and an external resistor 110, which is provided outside the pressure measuring device, and one end of which is connected to the second connection pad 105b, and the other end is connected to the ground.

[0039] The wiring 107 is formed on the diaphragm layer 101 which is made of n-type single crystal silicon whose main surface is set to the (100) plane. <100> The wiring 107 is formed by extending in the direction of 10 on the diaphragm layer 101 composed of n-type single crystal silicon. 19 (atoms / cm 3 ) as a p-type impurity, thereby forming a p-type semiconductor diffusion resistor.

[0040] In this example, the four resistor elements, namely, the first resistor element 103a, the second resistor element 103b, the third resistor element 103c, and the fourth resistor element 103d, are arranged at equal intervals in the circumferential direction of the pressure receiving region 102. In addition, the longitudinal direction of the first resistor element 103a, the second resistor element 103b, the third resistor element 103c, and the fourth resistor element 103d is the direction in which the current flows, and this direction is the direction in which the main surface of the diaphragm layer 101 is set to the (100) plane. <110> direction.

[0041] In addition, the first connection pad 105a is connected to one end of the first resistor element 103a, the other end of the first resistor element 103a is connected to one end of the second resistor element 103b, and the other end of the second resistor element 103b is connected to the third connection pad 105c. In addition, the first connection pad 105a is connected to one end of the third resistor element 103c, the other end of the third resistor element 103c is connected to one end of the fourth resistor element 103d, and the other end of the fourth resistor element 103d is connected to the fourth connection pad 105d.

[0042] A fifth connection pad 105e is connected to a line connecting the other end of the first resistor 103a and one end of the second resistor 103b, and a sixth connection pad 105f is connected to a line connecting the other end of the third resistor 103c and one end of the fourth resistor 103d.

[0043] In addition, the power supply 106 is connected to the first connection pad 105a and the third connection pad 105c. The "+" side of the power supply 106 is connected to the first connection pad 105a, and the "-" side of the power supply 106 is connected to the third connection pad 105c. In addition, the parts where there are multiple ground connection parts in the figure indicate that they are connected, the second connection pad 105b is connected to the ground via a predetermined external resistor 110, and the fourth connection pad 105d is directly connected to the ground.

[0044] In addition, the pressure calculation unit 108 obtains the pressure value received by the pressure-receiving area 102 based on the signal output from the above-mentioned first bridge circuit. The pressure calculation unit 108 corrects the signal output from the first bridge circuit based on the potential value between the first connection pad 105a and the second connection pad 105b to which the temperature measuring element 104 is connected, that is, based on the measured temperature output of the second bridge circuit, and obtains the temperature-corrected pressure value received by the pressure-receiving area 102 based on the corrected signal. In addition, the correction signal may be a static pressure measurement signal or the like in addition to the temperature. In this example, as described above, the pressure calculation unit 108 obtains the true pressure value received by the pressure-receiving area 102 based on the outputs from the fifth connection pad 105e and the sixth connection pad 105f in a state where each resistor element and each connection pad are connected.

[0045] In addition, the determination unit 109 determines the failure of the pressure-receiving region 102 based on the potential value between the first connection pad 105a and the second connection pad 105b, that is, based on the measured temperature output of the second bridge circuit. For example, when the pressure-receiving region 102 is damaged and the wiring 107 passing through the pressure-receiving region 102 is disconnected, the power supplied from the power supply 106 to the temperature measuring element 104 becomes 0, and the potential of the second connection pad 105b becomes 0. The determination unit 109 can determine that the pressure-receiving region 102 is damaged by detecting the above-mentioned state.

[0046] As described above, according to the first embodiment, by passing the wiring 107 connecting the first connection pad 105a and one end of the temperature measuring element 104 over the pressure receiving area 102, it is possible to perform a fault diagnosis of the pressure measuring device without adding a signal to be processed. <100> The pressure-receiving area 102 can be relaxed by extending in the longitudinal direction.

[0047] However, if Figure 2 As shown, a portion of the temperature measuring element 104a may also be formed on the pressure-bearing area 102. Other Configurations and Uses Figure 1A , Figure 1B The pressure measuring device is the same as described above. Figure 3 As shown, the temperature measuring element 104b may also be formed in the central part of the pressure receiving area 102. In this case, one end of the temperature measuring element 104b is connected to the second connection pad 105b by wiring 107b. In addition, the first connection pad 105a is connected to the other end of the temperature measuring element 104 by wiring 107a. Other structures and uses Figure 1A , Figure 1B The pressure measuring device described is the same.

[0048] In addition, if Figure 4 As shown, the polarity of the power source 106 may be oppositely applied to the first bridge circuit and the second bridge circuit. For example, the "-" side of the power source 106 is connected to the first connection pad 105a, and the "+" side of the power source 106 is connected to the third connection pad 105c. Other Configurations and Uses Figure 1A , Figure 1B In this structure, when the pressure receiving area 102 is damaged and the wiring 107a or the wiring 107b is disconnected, the power supplied from the power supply 106 to the temperature measuring element 104b becomes 0, and the potential of the second connection pad 105b becomes the potential supplied from the power supply 106 (potential value V in The determination unit 109 detects that the potential of the second connection pad 105b has reached the potential value V in , it can be determined that the pressure-bearing area 102 is damaged.

[0049] [Implementation Method 2]

[0050] Next, refer to Figure 5 A pressure measuring device according to a second embodiment of the present invention will be described. The pressure measuring device includes a pressure sensor having a diaphragm layer 201. The diaphragm layer 201 may be made of, for example, single crystal silicon whose main surface is a (100) plane. A first pressure receiving region 202a and a second pressure receiving region 202b are formed on the diaphragm layer 201. The first pressure receiving region 202a and the second pressure receiving region 202b are each circular in plan view, for example.

[0051] The diaphragm layer 201 is formed on a substrate (not shown), for example, and two through holes are formed on the substrate that penetrate the substrate in the thickness direction. The first pressure-bearing region 202a and the second pressure-bearing region 202b are regions of a portion of the diaphragm layer 201 defined by the spaces between the two through holes. These structures are the same as those in the first embodiment.

[0052] Two resistor elements, namely, a first resistor element 203a and a second resistor element 203b, are provided on the diaphragm layer 201 at the periphery of the first pressure-bearing region 202a for measuring the strain of the first pressure-bearing region 202a by the piezoresistance effect. In addition, two resistor elements, namely, a third resistor element 203c and a fourth resistor element 203d, are provided on the diaphragm layer 201 at the periphery of the second pressure-bearing region 202b for measuring the strain of the second pressure-bearing region 202b by the piezoresistance effect. These resistor elements are arranged at the locations where the piezoelectric effect is generated in each pressure-bearing region. The above-mentioned resistor element can be composed of, for example, a p-type region, which is a predetermined location of the diaphragm layer 201 composed of n-type single crystal silicon with the main surface set as a (100) plane, for example, with a 10 18 (atoms / cm 3 ) is introduced as a p-type impurity, boron (B), at a concentration of approximately 1.5 Å.

[0053] Each resistor element is rectangular in shape when viewed from above, and the length direction of the rectangle is in the direction of the silicon single crystal. <110> Furthermore, the first resistance element 203a and the second resistance element 203b form a first bridge circuit, and the third resistance element 203c and the fourth resistance element 203d form a third bridge circuit.

[0054] In addition, a temperature measuring element 204 is provided on the diaphragm layer 201. The temperature measuring element 204 can be arranged on the diaphragm layer 201 outside the first pressure-bearing region 202a and the second pressure-bearing region 202b. For example, the temperature measuring element 204 can be arranged on the diaphragm layer 201 between the first pressure-bearing region 202a and the second pressure-bearing region 202b. The temperature measuring element 204 can be composed of, for example, a p-type region, which is a predetermined portion of the diaphragm layer 201 formed of n-type single crystal silicon, with a 10 18 (atoms / cm 3 ) is formed by introducing B as a p-type impurity at a concentration of about ).

[0055] A first connection pad 205a is formed on the diaphragm layer 201 outside the first pressure-bearing region 202a and the second pressure-bearing region 202b to connect the bridge circuit and the power source 206. In addition, a first wiring 207a is formed on the diaphragm layer 201 to connect the first connection pad 205a and one end of the temperature measuring element 204 through the first pressure-bearing region 202a.

[0056] In addition, a second connection pad 205b is formed on the diaphragm layer 201 outside the first pressure-bearing region 202a and the second pressure-bearing region 202b. In addition, a second wiring 207b is formed on the diaphragm layer 201 to connect the second connection pad 205b and the other end of the temperature measuring element 204 through the second pressure-bearing region 202b. The first wiring 207a and the second wiring 207b are wirings formed on the diaphragm layer 201 to connect the first connection pad 205a and the second connection pad 205b through the first pressure-bearing region 202a and the second pressure-bearing region 202b via the temperature measuring element 204. In addition, a second bridge circuit is formed by the temperature measuring element 204 and the external resistor 210, which is provided outside the pressure measuring device, and one end of which is connected to the second connection pad 205b and the other end is connected to the ground.

[0057] The first wiring 207a and the second wiring 207b are respectively formed on the diaphragm layer 201 made of single crystal silicon whose main surface is set to the (100) plane. <100> The first wiring 207a and the second wiring 207b can be formed by, for example, adding 10% B as a p-type impurity to the diaphragm layer 201 made of n-type single crystal silicon. 19 (atoms / cm 3 ) is introduced to form a concentration of about ).

[0058] In this example, the first connection pad 205a is connected to one end of the first resistor element 203a, the other end of the first resistor element 203a is connected to one end of the second resistor element 203b, and the other end of the second resistor element 203b is connected to the third connection pad 205c. In addition, the first connection pad 205a is connected to one end of the third resistor element 203c, the other end of the third resistor element 203c is connected to one end of the fourth resistor element 203d, and the other end of the fourth resistor element 203d is connected to the fourth connection pad 205d.

[0059] A fifth connection pad 205e is connected to a wiring line connecting the other end of the first resistor 203a and one end of the second resistor 203b, and a sixth connection pad 205f is connected to a wiring line connecting the other end of the third resistor 203c and one end of the fourth resistor 203d.

[0060] In addition, the power supply 206 is connected to the first connection pad 205a and the third connection pad 205c. The "+" side of the power supply 206 is connected to the first connection pad 205a, and the "-" side of the power supply 206 is connected to the third connection pad 205c. In addition, in the figure, the parts where there are multiple ground connection parts indicate that they are connected, the second connection pad 205b is connected to the ground via a predetermined resistor, and the fourth connection pad 205d is directly connected to the ground.

[0061] In addition, although not shown in the figure, the pressure measuring device of the second embodiment includes a pressure calculating unit, which corrects the signal output from the first bridge circuit (the potential value of the fifth connecting pad 205e) and the signal output from the third bridge circuit (the potential value of the sixth connecting pad 205f) based on the potential value between the first connecting pad 205a and the second connecting pad 205b, that is, based on the measured temperature output of the second bridge circuit including the temperature measuring element 204, and obtains the value of the pressure difference between the pressure received by the first pressure receiving area 202a and the pressure received by the second pressure receiving area 202b based on the corrected signals. The correction signal may be a static pressure measurement signal or the like in addition to the temperature. In this example, as described above, the pressure calculating unit obtains the difference between the pressure value received by the first pressure receiving area 202a and the pressure value received by the second pressure receiving area 202b based on the outputs from the fifth connecting pad 205e and the sixth connecting pad 205f in a state where each resistor element and each connecting pad are connected.

[0062] Although not shown, the pressure measuring device of the second embodiment includes a determination unit that determines whether the diaphragm layer 201 is damaged based on the potential value between the first connection pad 205a and the second connection pad 205b, that is, the measured temperature output of the second bridge circuit including the temperature measuring element 204. For example, when the diaphragm layer 201 is damaged and the first wiring 207a or the second wiring 207b is disconnected, the power supplied from the power supply 206 to the temperature measuring element 204 becomes 0, and the potential of the second connection pad 205b becomes 0. By detecting the above-mentioned state, the determination unit can determine that the diaphragm layer 201 (the first pressure receiving region 202a and the second pressure receiving region 202b) is damaged.

[0063] As described above, according to the second embodiment, the first wiring 207a and the second wiring 207b connected to the temperature measuring element 204 are passed over the first pressure receiving area 202a and the second pressure receiving area 202b, so that the fault diagnosis of the pressure measuring device can be performed without adding a signal to be processed. <100> The first pressure receiving region 202a and the second pressure receiving region 202b can be extended in the longitudinal direction to alleviate the influence of the pressure received by the first pressure receiving region 202a and the second pressure receiving region 202b.

[0064] However, if Figure 6 As shown in FIG. 1 , the first wiring 207a, the temperature measuring element 204, and the second wiring 207b may be arranged (arranged) on the same straight line (the straight line on the lower layer) in a plan view. Figure 7 As shown, a part of the temperature measuring element 204a may be formed on the first pressure receiving area 202a and the second pressure receiving area 202b.

[0065] In addition, if Figure 8 As shown, it can also be based on Figure 5 The configuration is such that the polarity of the power source 206 is applied to the first bridge circuit, the second bridge circuit, and the third bridge circuit in opposite directions. Specifically, the "-" side of the power source 206 is connected to the first connection pad 205a, and the "+" side of the power source 206 is connected to the third connection pad 205c. In addition, the third connection pad 205c and the fourth connection pad 205d are connected. Other configurations and uses Figure 5 In this configuration, when the diaphragm layer 201 is damaged and the first wiring 207a or the second wiring 207b is disconnected, the power supplied from the power supply 206 to the temperature measuring element 204 becomes 0, and the potential of the second connection pad 205b becomes the potential supplied from the power supply 206 (potential value V in The determination unit detects that the potential of the second connection pad 205b reaches the potential value V in, it can be determined that damage has occurred in the first pressure receiving area 202a or the second pressure receiving area 202b.

[0066] As described above, according to the present invention, by passing the wiring connected to the temperature measuring element over the pressure receiving region, it is possible to perform a fault diagnosis of the pressure measuring device without adding a signal to be processed.

[0067] The present invention is not limited to the above-described embodiments, and it is obvious that a person having ordinary knowledge in the art can implement various modifications and combinations within the technical concept of the present invention.

[0068] Explanation of symbols

[0069] 101, 201 ... diaphragm layer, 102, 202a, 202b ... pressure receiving region, 103a, 203a ... first resistor element,

[0070] 103b, 203b…second resistance element, 103c, 203c…third resistance element, 103d, 203d…fourth resistance element, 104, 204…temperature measuring element, 105a, 205a…first connecting pad, 105b, 205b…second connecting pad, 105c, 205c…third connecting pad, 105d, 205d…fourth connecting pad, 105e, 205e…fifth connecting pad, 105f, 205…sixth connecting pad, 106, 206…power supply, 107, 207a, 207b…wiring, 108…pressure calculating unit, 109…judgment unit, 110, 210…external resistor, 111…substrate, 112…through hole.

Claims

1. A pressure measuring device, characterized in that: have: Diaphragm layer; a pressure-bearing region formed in the diaphragm layer; a first bridge circuit, which is composed of one or more resistor elements provided in the diaphragm layer and measures the strain of the pressure-bearing area by the piezoresistance effect; A temperature measuring element, which is arranged on the diaphragm layer; A second bridge circuit includes the temperature measuring element, wherein wiring connected to the temperature measuring element is provided throughout the entire pressure receiving area and outputs the temperature measured by the temperature measuring element; as well as a determination unit configured to determine a failure in the pressure receiving area based on an output of the second bridge circuit, The diaphragm layer is composed of n-type single crystal silicon with the main surface being the (100) plane. <100> The p-type semiconductor diffusion resistor is formed by extending in the direction of <100> Extend in direction.

2. The pressure measuring device according to claim 1, characterized in that: have: a first connection pad formed on the diaphragm layer outside the pressure-bearing region and connecting the second bridge circuit and a power source; a second connecting pad formed on the diaphragm layer outside the pressure-bearing region and connected to one end of the temperature measuring element; as well as A wiring is formed on the diaphragm layer and connects the first connection pad and the second connection pad via the temperature measuring element and through the pressure receiving region.

3. The pressure measuring device according to claim 1, characterized in that: have: a first connection pad formed on the diaphragm layer outside the pressure-bearing region and connected to the second bridge circuit and a ground line; a second connecting pad formed on the diaphragm layer outside the pressure-bearing region and connected to one end of the temperature measuring element; as well as A wiring is formed on the diaphragm layer and connects the first connection pad and the second connection pad via the temperature measuring element and through the pressure receiving region.

4. A pressure measuring device, characterized in that: have: Diaphragm layer; a first pressure-bearing region and a second pressure-bearing region, which are formed in the diaphragm layer; a first bridge circuit, which is composed of one or more resistor elements provided in the diaphragm layer and measures the strain of the first pressure-bearing area by the piezoresistance effect; A temperature measuring element, which is arranged on the diaphragm layer; a second bridge circuit, comprising the temperature measuring element, wherein wiring connected to the temperature measuring element is arranged throughout the first pressure receiving area and the second pressure receiving area, and outputs the temperature measured by the temperature measuring element; a third bridge circuit, which is composed of one or more resistor elements provided in the diaphragm layer and measures the strain of the second pressure-receiving region by the piezoresistance effect; and a determination unit configured to determine failures in the first pressure-receiving region and the second pressure-receiving region based on an output of the second bridge circuit, The diaphragm layer is composed of n-type single crystal silicon with the main surface being the (100) plane. <100> The p-type semiconductor diffusion resistor is formed by extending in the direction of <100> Extend in direction.

5. The pressure measuring device according to claim 4, characterized in that: have: a first connection pad formed on the diaphragm layer outside the first pressure-bearing region and the second pressure-bearing region, and connecting the second bridge circuit and a power source; a second connecting pad formed on the diaphragm layer outside the first pressure-bearing region and the second pressure-bearing region and connected to one end of the temperature measuring element; as well as A wiring is formed on the diaphragm layer and connects the first connection pad and the second connection pad via the temperature measuring element and through the first pressure receiving region and the second pressure receiving region.

6. The pressure measuring device according to claim 4, characterized in that: have: a first connection pad formed on the diaphragm layer outside the first pressure-bearing region and the second pressure-bearing region, and connected to the second bridge circuit and a ground line; a second connecting pad formed on the diaphragm layer outside the first pressure-bearing region and the second pressure-bearing region and connected to one end of the temperature measuring element; as well as A wiring is formed on the diaphragm layer and connects the first connection pad and the second connection pad via the temperature measuring element and through the first pressure receiving region and the second pressure receiving region.

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