JP2011174876A - Sensor device having substrate having diaphragm, and sensor device array having plural sensor devices - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sensor device which readily detects breakages. <P>SOLUTION: The sensor device includes a substrate 65 having a diaphragm 100. The diaphragm 100 includes a wiring 111 for a sensor electrically connected to a plurality of electrodes 120 for sensors; a sensor element 110 electrically connected to the wiring 111 for the sensor and is formed to be capable of measuring a specific physical quantity; and a breakage detecting wiring 150, that is electrically connected to a plurality of breakage detection electrodes 140 and is formed so that it is disconnected by a breakage generated in the diaphragm 100. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  One aspect of the present invention is a sensor device, and particularly includes a substrate having a breakage detection wiring formed so as to be disconnected due to a breakage occurring in a diaphragm portion.

  2. Description of the Related Art A sensor device such as a MEMS (Micro Electro Mechanical Systems) type flow sensor, infrared sensor, or gas sensor includes a heater and a sensor element on a substrate. The lower base of the heater and sensor element is etched, thereby forming a diaphragm on the substrate. In this way, the diaphragm is formed on the base, thereby achieving thermal insulation between the heater and the sensor element in the sensor device and the base.

  The diaphragm in such a sensor device is formed thin, and breakage such as cracks or cracks is likely to occur. If the diaphragm is damaged, the sensor device may not operate properly. Therefore, as a technique for detecting such breakage, for example, there is a technique described in JP-A-2002-195958 (Patent Document 1).

JP 2002-195958 A

  However, in the inspection process, if the technique described in Patent Document 1, the method of detecting damage based on the presence or absence of energization of the heater and the sensor element, or the method of detecting damage visually by using a microscope or the like, the damage is accurately detected. It is difficult to detect. In addition, there is a problem that inspection takes a long time and inspection costs increase.

  Furthermore, if a malfunction occurs while using the sensor device, it is difficult to immediately check whether the malfunction is due to damage, so it is difficult to determine whether the malfunction is due to breakage on site. There are also challenges.

  Therefore, an object of one embodiment of the present invention is to provide a sensor device that can solve the above-described problems.

  In order to solve this problem, a sensor device according to an aspect of the present invention is a sensor device including a substrate having a diaphragm portion, and the diaphragm portion is electrically connected to a plurality of sensor electrodes. A sensor wire, a sensor element that is electrically connected to the sensor wire and capable of measuring a specific physical quantity, and is electrically connected to a plurality of breakage detection electrodes, is formed in the diaphragm portion. Breakage detection wiring formed so as to be disconnected due to breakage.

  According to the sensor device having such a configuration, it is possible to detect breakage occurring in the diaphragm portion by an electrical method using breakage detection wiring. Thereby, the inspection cost for detecting the breakage in the diaphragm portion can be reduced. Further, when an abnormality occurs in the sensor device, it is possible to detect breakage without removing the sensor device from the piping or the like. Furthermore, since the breakage detection wiring can be formed of the same material as the sensor element and the sensor wiring, and can be formed by the same process, the present invention can be easily applied.

  The diaphragm portion may include a plurality of slits arranged in a straight line, and the breakage detection wiring may be arranged between the plurality of slits.

  According to such a configuration, since the breakage detection wiring is arranged between the slits that are likely to be broken, it is possible to effectively detect the breakage with a small-scale configuration.

  Alternatively, the diaphragm portion may include a slit, and the breakage detection wiring may be formed so as to surround the slit.

  According to such a configuration, since the breakage detection wiring is arranged around the slit that is likely to be broken, it is possible to effectively detect the breakage with a small-scale configuration.

  Further, the breakage detection wiring may be formed through the end side of the diaphragm portion.

  According to such a configuration, since the breakage detection wiring is arranged near the end of the diaphragm portion where breakage is likely to occur, it is possible to effectively perform breakage detection with a small-scale configuration.

  The diaphragm section preferably includes a plurality of breakage detection wires, and the substrate includes a plurality of breakage detection electrode pairs electrically connected to each of the plurality of breakage detection wires. .

  According to such a configuration, it is possible to identify a specific breakage point by identifying which breakage detection wiring is disconnected among the plurality of breakage detection wirings.

  The sensor device further includes a base, the base includes a recess on a surface facing the substrate, the diaphragm portion is formed to cover the recess, and the sensor substrate includes: A plurality of sensor electrodes and the plurality of breakage detection electrodes may be provided.

  Further, it is preferable that the breakage detection wiring is arranged symmetrically with respect to the center of the diaphragm portion in plan view.

  A local change in temperature distribution and uniform flow velocity distribution formed symmetrically at the center of the diaphragm part adversely affects the function and performance of the sensor device. According to this configuration, it is possible to avoid local changes in the temperature distribution and the flow velocity distribution due to the breakage detection wiring. Thereby, it is possible to prevent the damage detection wiring from affecting the function / performance of the sensor device.

  The sensor device array according to one embodiment of the present invention includes a plurality of the sensor devices, and the breakage detection electrode of the first sensor device and the breakage detection electrode of the second sensor device are electrically connected. Connected.

  According to such a configuration, it is possible to detect damage in a plurality of sensor devices at a time in the manufacturing process or the inspection process. As a result, it is possible to reduce the time and cost required for the inspection for identifying defective products.

  According to one aspect of the present invention, for example, it is possible to obtain an effect that it is possible to easily detect breakage occurring in the diaphragm portion by an electrical method.

The perspective view of a sensor apparatus. Sectional drawing of a sensor apparatus. The top view of the 1st structural example of the sensor apparatus which has a damage detection wiring. The top view of the 2nd structural example of the sensor apparatus which has a damage detection wiring. The top view of the 3rd structural example of the sensor apparatus which has a damage detection wiring. The top view of the 4th example of composition of a sensor device which has breakage detection wiring. The top view of the 5th structural example of the sensor apparatus which has a damage detection wiring. The top view of the structural example of the sensor apparatus array which has a damage detection wiring.

An embodiment according to the present invention will be specifically described according to the following configuration with reference to the drawings. However, the embodiment described below is merely an example of the present invention, and does not limit the technical scope of the present invention. In addition, in each drawing, the same code | symbol is attached | subjected to the same component and the description may be abbreviate | omitted.
1. Definition 2. Embodiments (1) Configuration example of sensor device (2) Configuration example 1 of sensor device having breakage detection wiring
(3) Configuration example 2 of sensor device having breakage detection wiring
(4) Configuration example 3 of sensor device having breakage detection wiring
(5) Configuration example 4 of sensor device having breakage detection wiring
(6) Configuration example 5 of sensor device having breakage detection wiring
(7) Configuration example of sensor device array having breakage detection wiring Supplement

<1. Definition>
First, terms used in this specification are defined as follows.

  “Fracture”: includes physical changes such as cracking, cracking or breaking. In particular, in the present application, it refers to a physical change such as a crack, a crack, or a break that may cause a breakage in the breakage detection wiring.

<2. Embodiment>
One embodiment of the present invention is a sensor device including a breakage detection wiring as described below. Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<(1) Configuration example of sensor device>
FIG. 1 is a perspective view of a flow sensor as an example of a sensor device, and FIG.
The cross-sectional view seen from -II direction is shown.

  The flow sensor 8 that detects the flow rate or flow rate of the fluid includes a base 60 provided with a recess (also referred to as a “cavity”) 66 and a substrate 65 disposed on the base 60 so as to cover the recess 66. Configured. The substrate 65 includes a heater 61, an upstream temperature measuring resistance element 62 provided upstream from the heater 61, a downstream temperature measuring resistance element 63 provided downstream from the heater 61, and an upstream temperature measuring resistance element 62. An ambient temperature sensor 64 is provided on the upstream side.

  A portion of the substrate 65 covering the recess 66 forms a heat-insulating diaphragm portion 100. The ambient temperature sensor 64 measures the temperature of the fluid that has flowed into a branch channel (not shown) in which the flow sensor 8 is disposed. The heater 61 is disposed at the center of the substrate 65 that covers the recess 66, and heats the fluid flowing through the branch flow path so as to be higher than the temperature measured by the ambient temperature sensor 64, for example, by 10 ° C. The upstream temperature measuring resistance element 62 detects the temperature upstream of the heater 61, and the downstream temperature measuring resistance element 63 is used to detect the temperature downstream of the heater 61.

  Here, when the fluid in the flow path where the flow sensor 8 is disposed is stationary, the heat applied by the heater 61 is diffused symmetrically in the upstream direction and the downstream direction. Accordingly, the temperatures of the upstream resistance temperature element 62 and the downstream resistance temperature element 63 are equal, and the electrical resistances of the upstream resistance temperature element 62 and the downstream resistance temperature element 63 are equal.

  On the other hand, when the fluid in the branch channel in which the flow sensor 8 is arranged flows from upstream to downstream, the heat applied by the heater 61 is carried in the downstream direction. Therefore, the temperature of the downstream resistance temperature element 63 is higher than the temperature of the upstream resistance temperature element 62. Therefore, there is a difference between the electrical resistance of the upstream side resistance thermometer element 62 and the electrical resistance of the downstream side resistance thermometer element 63.

  As described above, the difference between the electric resistance of the upstream temperature measuring resistance element 62 and the electric resistance of the downstream temperature measuring resistance element 63 has a correlation with the velocity of the fluid in the flow path in which the flow sensor 8 is disposed. Therefore, based on the difference between the electrical resistance of the upstream resistance temperature sensor 62 and the electrical resistance of the downstream resistance temperature element 63, the flow rate of the fluid flowing through the branch flow path can be obtained.

As a material of the base 60, silicon (Si) or the like can be used. As a material of the substrate 65, silicon oxide (SiO ₂ ) or the like can be used. The recess 66 is formed by anisotropic etching or the like. Further, platinum (Pt) or the like can be used as the material of the heater 61, the upstream temperature measuring resistance element 62, the downstream temperature measuring resistance element 63, and the ambient temperature sensor 64, and can be formed by lithography or the like. .

<(2) Configuration Example 1 of Sensor Device Having Breakage Detection Wiring>
FIG. 3 is a plan view showing a first configuration example of a sensor device having a breakage detection wiring which is one of the features of the present invention.

  As shown in FIG. 3, the substrate 65 includes a sensor element 110, a sensor wire 111, a sensor electrode 120, a slit 130, a breakage detection wire 150, and a breakage detection electrode 140. The diaphragm portion 100 in the substrate 65 is formed so as to overlap with the concave portion 66 provided in the base 60 in plan view. A sensor element 110, a sensor wiring 111, a slit 130, and a breakage detection wiring 150 are formed on the diaphragm unit 100.

  The sensor electrode 120 is electrically connected to the sensor wiring 111. The sensor wiring 111 is electrically connected to the sensor element 110. The breakage detection electrode 140 is electrically connected to the breakage detection wiring 150. As shown in FIG. 3, the breakage detection wiring 150 is formed so as to pass between two slits 130 connected in a straight line. Further, the breakage detection wiring 150 is also arranged so as to pass near the slit 130. The slit 130 is provided for etching the base 60 through the slit 130 to form the recess 66. The sensor element 110 is formed so that a physical quantity such as temperature can be measured via the sensor electrode 120.

  In the substrate 65 used in the sensor device shown in FIG. 3, a slit 130 is formed so as to connect the concave portion 66 of the base 60 and the flow path located on the opposite side of the base 60 with respect to the substrate 65. In the vicinity of the slit 130, damage is likely to occur. In particular, damage is likely to occur between two slits connected so as to extend on one straight line. Further, the peripheral portion of the diaphragm portion 100 is easily damaged due to the influence of stress. Therefore, the breakage detection wiring 150 is arranged so as to pass through the portion where the breakage easily occurs, and the breakage detection wiring 150 is disconnected when the breakage occurs. Then, by energizing the breakage detection electrode 140, it is possible to detect whether or not breakage has occurred at the location where the breakage detection wiring 150 is disposed.

  That is, according to the sensor device including the substrate 65 shown in FIG. 3, the breakage occurring in the diaphragm unit 100 can be detected by an electrical method using the breakage detection wiring 150. Thereby, the inspection cost for detecting the breakage in the diaphragm portion can be reduced. Further, when an abnormality occurs in the sensor device, it is possible to detect breakage without removing the sensor device from piping or the like where the sensor device is installed. Furthermore, the breakage detection wiring 150 can be formed of the same material as the sensor element 110 and the sensor wiring 111 and can be easily implemented because it can be formed by the same process.

  Further, if the breakage detection wiring 150 is disposed between the slits 130 that are likely to be damaged, the breakage detection can be effectively detected with a small-scale configuration as compared with the configuration in which the breakage detection wiring 150 is disposed on the entire diaphragm unit 100. Can be done.

  In the substrate 65 shown in FIG. 3, the breakage detection wiring 150 is formed symmetrically with respect to the center of the diaphragm portion 100. Thus, it is preferable to arrange the breakage detection wiring 150 symmetrically with respect to the center of the diaphragm portion 100 in a plan view. This is because it is possible to avoid local changes in the temperature distribution and the uniform flow velocity distribution formed symmetrically at the center of the diaphragm portion. That is, by arranging the breakage detection wiring 150 symmetrically, it is possible to prevent the breakage detection wiring 150 from affecting the function / performance of the sensor device.

  The first configuration example is merely one configuration example, and various other configurations can be considered. Hereinafter, another configuration example will be specifically described. However, the configuration example described below is also a configuration example, and does not cover all aspects of the present invention. That is, according to one aspect of the present invention, it is technically significant that the breakage detection wiring 150 is provided at least in the diaphragm portion 100 that is easily damaged as described above.

<(3) Configuration Example 2 of Sensor Device Having Breakage Detection Wiring>
FIG. 4 is a plan view showing a second configuration example of the sensor device. Compared to the first configuration example of the sensor device shown in FIG. 3, the arrangement of the breakage detection wiring 150 is different.

  As described above, the peripheral portion of the diaphragm portion 100 is also a place where damage is likely to occur. Therefore, in the present configuration example, the breakage detection wiring 150 is disposed along the end side of the diaphragm unit 100. If the breakage detection wiring 150 is arranged in this way, the breakage detection wiring is arranged near the edge of the diaphragm portion where damage is likely to occur. Thus, it becomes possible to detect damage effectively with a small-scale configuration.

  Note that the breakage detection wiring 150 is not necessarily arranged along the end side of the diaphragm unit 100, and may be arranged through the end side of the diaphragm unit 100. For example, various forms are conceivable, such as being arranged across the edge of the diaphragm unit 100.

<(4) Configuration Example 3 of Sensor Device Having Breakage Detection Wiring>
FIG. 5 is a plan view showing a third configuration example of the sensor device. Compared to the first configuration example of the sensor device shown in FIG. 3, the arrangement of the breakage detection wiring 150 is different.

  As described above, the periphery of the slit 130 is a place where damage is likely to occur. Therefore, in this configuration example, a plurality of breakage detection wirings 150 are arranged in the vicinity of the periphery of the slit 130, and are formed independently on the right side and the left side of the sensor element 110, respectively.

  If the breakage detection wiring 150 is formed so as to surround the slit 130 in this way, the breakage detection wiring 150 is disposed at a place where the breakage is likely to occur, as compared with the case where the breakage detection wiring 150 is arranged on the entire diaphragm portion 100. Will be. Therefore, it becomes possible to detect damage effectively with a relatively small configuration.

  In the second configuration example, a plurality of combinations of the breakage detection wiring 150 and the breakage detection electrode 140 are formed. If comprised in this way, it will become possible to specify which damage detection wiring 150 was disconnected among several damage detection wiring 150, and it will become possible to specify a specific damage location.

  For example, it is assumed that a breakage occurs around the slit 130 located at the upper left in FIG. 5 and a breakage occurs in the breakage detection wiring 150 on the left side. In this case, no current flows even if a voltage is applied to the damage detection electrode 140 on the left side. On the other hand, if a voltage is applied to the right damage detection electrode 140, a current flows. Therefore, it is possible to detect that a disconnection has occurred somewhere in the damage detection wiring 150 where no current flows even when a voltage is applied.

<(5) Configuration Example 4 of Sensor Device Having Damage Detection Wiring>
FIG. 6 is a plan view showing a fourth configuration example of the sensor device. Compared with the third configuration example of the sensor device shown in FIG. 5, in this configuration example, the breakage detection wiring 150 is formed around each of the four slits 130. By arranging a plurality of breakage detection wirings 150 in this way, it is possible to easily identify a specific breakage point in the diaphragm unit 100.

  In this configuration example, one breakage detection wiring 150 is arranged around each of the plurality of slits 130. However, a configuration in which the breakage detection wiring 150 is further disposed so as to pass through the end side of the diaphragm unit 100 is also conceivable. .

<(6) Configuration Example 5 of Sensor Device Having Damage Detection Wiring>
FIG. 7 is a plan view showing a fifth configuration example of the sensor device. In the present configuration example, the first breakage detection wiring 150 disposed through the edge of the diaphragm unit 100 and the second breakage detection wiring disposed so as to pass between the plurality of slits 130 provided on the left and right sides. 150 is formed. If comprised in this way, it will become possible to detect effectively the location which is easy to produce damage with a small structure.

<(7) Configuration Example of Sensor Device Array Having Damage Detection Wiring>
FIG. 8 is a diagram illustrating a configuration example of a sensor device array including a plurality of sensor devices. As shown in FIG. 8, each of the plurality of sensor devices constituting the sensor device array includes a breakage detection wiring 150. Furthermore, the breakage detection electrode 140 in one sensor device is connected in series via the breakage detection electrode 140 in the adjacent sensor device and the inter-sensor device wiring 160. The damage detection wiring 150 and the sensor device wiring 160 in the plurality of sensor devices constitute one closed circuit, and the damage detection electrode 140a and the damage detection electrode 140b serve as terminals of the closed circuit.

  According to the sensor device array configured as described above, is a breakage occurring in the breakage detection wiring 150 included in the plurality of sensor devices by applying a voltage between the breakage detection electrode 140a and the breakage detection electrode 140b? It becomes possible to inspect whether or not. Therefore, for example, in the inspection process, it is possible to detect damage in a plurality of sensor devices at a time. According to this, it is possible to reduce the time and cost required for the inspection.

  Note that the number of sensor devices constituting the sensor device array can be arbitrarily set according to the size of the sensor device and the defect occurrence rate.

<3. Supplement>
As described above, the sensor device having the breakage detection wiring has been described with reference to a plurality of configuration examples. However, the present invention is not limited to these configuration examples, and includes various forms conceivable from these configuration examples.

  For example, it is good also as a structure further equipped with a heater on the diaphragm part 100. In this case, the diaphragm unit 100 includes a heater and heater wiring electrically connected to the heater, and a heater electrode is formed on the substrate 65 other than the diaphragm unit 100.

  Further, a mode in which an appropriate number of breakage detection wirings 150 are arranged according to the number of slits 130 is also conceivable.

  In the embodiment, the flow sensor has been described as an example. However, a device to which the sensor device according to one embodiment of the present invention can be applied is not limited to the flow sensor, and can be applied to various MEMS sensors.

  The sensor device of the present invention can be applied to various MEMS type sensors such as a flow sensor used in a flow meter.

8... Sensor 60... Base 61... Heater 62... Upstream temperature measuring resistor element 63... Downstream temperature measuring resistor element 64 .. Ambient temperature sensor 65. 110 ... Sensor element 111 ... Sensor wiring 120 ... Sensor electrode 130 ... Slit 140 / 140a / 140b ... Damage detection electrode 150 ... Damage detection wiring 160 ... Wiring between sensor devices

Claims (8)

A sensor device including a substrate having a diaphragm portion,
The diaphragm part is
Sensor wiring electrically connected to a plurality of sensor electrodes;
A sensor element that is electrically connected to the sensor wiring and formed to be capable of measuring a specific physical quantity;
A breakage detection wiring formed to be electrically connected to a plurality of breakage detection electrodes and formed to be disconnected due to breakage caused in the diaphragm portion, and
Sensor device. The diaphragm portion includes a plurality of slits arranged in a straight line,
The breakage detection wiring is formed to pass between the plurality of slits,
The sensor device according to claim 1. The diaphragm part includes a slit,
The breakage detection wiring is formed so as to surround the slit,
The sensor device according to claim 1. The breakage detection wiring is formed through an end side of the diaphragm part,
The sensor device according to claim 1. The diaphragm portion has a plurality of the breakage detection wires,
The board includes a plurality of breakage detection electrode pairs electrically connected to each of the plurality of breakage detection wirings,
The sensor device according to any one of claims 1 to 4. A sensor device further comprising a base,
The base includes a recess on a surface facing the substrate,
The diaphragm portion is formed so as to cover the concave portion,
The substrate includes the plurality of sensor electrodes and the plurality of breakage detection electrodes,
The sensor device according to any one of claims 1 to 5. The breakage detection wiring is arranged symmetrically with respect to the center of the diaphragm portion in plan view.
The sensor device according to any one of claims 1 to 6. A sensor device array comprising a plurality of sensor devices according to any one of claims 1 to 5,
The breakage detection electrode of the first sensor device and the breakage detection electrode of the second sensor device are electrically connected;
Sensor device array.

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