Capacitive sensor with temperature stable output

Abstract

An example system includes a sensor. The sensor includes a substrate having a substrate electrode and a first membrane suspended above the substrate. The first membrane includes a first membrane electrode. The first membrane is configured to deflect relative to the substrate electrode in response to an environmental condition. The sensor is operable to measure a capacitance between the substrate electrode and the first membrane electrode. The system also includes a first conductive shield positioned between the sensor and a device of the system that is operable to generate an electrical interference signal. The first conductive shield defines a plurality of first apertures extending through the first conductive shield. The system also includes a dielectric material disposed in the plurality of first apertures.

Description

[0001] This application is a divisional application. The original application is PCT application No. PCT / EP2019 / 060675, filed on April 25, 2019, which entered the Chinese national phase on October 19, 2020. The national application number is 201980026739.0, and the title is "Capacitive Sensor with Stable Temperature Output". Technical Field

[0002] This disclosure relates to capacitive sensors with stable temperature output. Background Technology

[0003] Microelectromechanical systems (MEMS) sensors can be used to measure environmental characteristics. As an example, a MEMS sensor can determine the ambient air pressure. Summary of the Invention

[0004] Integrated circuit (IC) devices can include integrated sensors that measure environmental characteristics based on capacitance changes between two electrodes. As an example, a pressure sensor can include a flexible diaphragm and a hermetically sealed cavity with a known atmospheric pressure (e.g., a reference pressure or gauge pressure) positioned on one side of the diaphragm. The opposite side of the flexible diaphragm is exposed to the environment and subjected to ambient atmospheric pressure. The flexible diaphragm deflects to varying degrees based on the pressure difference across its two sides. This degree of deflection can be determined by measuring the capacitance between a measuring electrode embedded in the diaphragm and a substrate electrode positioned near the diaphragm (e.g., along the opposite side of the cavity). Based on this measurement, the sensor can determine the ambient pressure of the environment.

[0005] Since the sensor's output depends on the capacitance measured between the base electrode and the measuring electrode, electrical interference to the sensor can reduce the accuracy and / or reliability of its measurement results. This electrical interference can be reduced by including a shielding layer (e.g., an aluminum plate) between the sensor and the source of electrical interference (e.g., other components of the IC device).

[0006] However, during repeated temperature cycling, the presence of large metal plates can sometimes adversely affect the accuracy and / or reliability of the sensor. For example, temperature changes can cause plastic deformation in the metal plate, leading to temperature-dependent output drift in the sensor and / or cracks or fractures in the IC device. Furthermore, temperature changes can alter the mechanical stress in the metal plate and cause temperature-dependent output drift in the sensor. Additionally, the sensor output may exhibit temperature-dependent hysteresis.

[0007] Various techniques can be used to mitigate these effects. In some embodiments, sensor performance can be improved by reducing the amount of metal in the CMOS back-end undergoing plastic deformation. As an example, this can be achieved by reducing the amount of metal in the shielding plate. As another example, mechanical stress in the shielding plate can be reduced, causing it to exhibit less plastic deformation in response to temperature changes. As yet another example, certain materials that are less prone to temperature-induced plastic deformation (e.g., titanium, titanium nitride, or copper) can be used in the shielding plate. As yet another example, the coefficient of thermal expansion of the shielding layer can be reduced to achieve lower thermal stress variations. As yet another example, the IC device can be designed to minimize or reduce the use of certain materials (e.g., aluminum) near the sensor. Therefore, the sensor remains shielded from electrical interference despite temperature changes, while its behavior is more stable and reliable.

[0008] In one aspect, the system includes a sensor. The sensor includes a substrate having a base electrode and a first membrane suspended above the substrate. The first membrane includes a first membrane electrode. The first membrane is configured to deflect relative to the base electrode in response to environmental conditions. The sensor is operable to measure the capacitance between the base electrode and the first membrane electrode. The system also includes a first conductive shielding layer positioned between the sensor and a device of the system operable to generate an electrical interference signal. The first conductive shielding layer defines a plurality of first holes extending through it. The system also includes a dielectric material disposed in the plurality of first holes.

[0009] Implementations of this aspect may include one or more of the following features.

[0010] In some embodiments, the length of the first membrane in the first direction can be greater than the length of the first membrane in the second direction orthogonal to the first direction. The length of each of the plurality of holes in the first direction can be greater than the length of that hole in the second direction.

[0011] In some embodiments, the first conductive shielding layer may include a plurality of conductive elements arranged in a grid. The plurality of conductive elements may be electrically interconnected with each other.

[0012] In some embodiments, the system may further include a second conductive shielding layer positioned between the sensor and the auxiliary device. The second conductive shielding layer may define a plurality of second holes extending through it. A dielectric material may be disposed in the plurality of second holes. The plurality of first holes may define a first pattern relative to the first conductive shielding layer. The plurality of second holes may define a second pattern relative to the second conductive shielding layer, the second pattern being different from the first pattern.

[0013] In some cases, a plurality of first holes can define a first pattern relative to a first conductive shielding layer. A plurality of second holes can define a second pattern relative to a second conductive shielding layer, with at least a portion of the first portion geometrically similar to at least a portion of the second portion. The second pattern can be spatially offset from the first pattern.

[0014] In some embodiments, the first conductive shielding layer may include a plurality of parallel first conductive segments. The first conductive segments may be electrically interconnected by a plurality of parallel second conductive segments perpendicular to the plurality of first conductive segments. The length of the first film in a first direction may be greater than the length of the first film in a second direction orthogonal to the first direction. The length of each of the plurality of first conductive segments in the first direction may be greater than the length of the first conductive segment in the second direction. The length of each of the plurality of first conductive segments in the second direction may be less than three times the thickness of the first conductive shielding layer in a third direction orthogonal to the first and second directions.

[0015] In some embodiments, the length of each of the plurality of first conductive segments in the second direction can be less than the thickness of the first conductive shielding layer in a third direction orthogonal to the first and second directions.

[0016] In some embodiments, the area of ​​the plurality of first holes in cross-section can be 40% to 90% of the total area of ​​the plurality of first conductive shielding layers.

[0017] In some implementations, the thickness of the first conductive shielding layer can be less than 0.8 μm.

[0018] In some implementations, the first conductive shielding layer may comprise aluminum.

[0019] In some embodiments, the first conductive shielding layer may further include a doped material. The doped material may be at least one of copper, scandium, or praseodymium.

[0020] In some embodiments, the first conductive shielding layer may include at least one of titanium, titanium nitride, or copper.

[0021] In some embodiments, a first conductive shielding layer can be positioned between the sensor and a plurality of devices operable to generate an electrical interference signal. The sensor is operable to shut down at least one of the plurality of devices when measuring the capacitance between the substrate electrode and the first film electrode.

[0022] In some implementations, the first environmental condition can be the pressure in the system's environment.

[0023] In some implementations, the first membrane and the substrate can define a first cavity.

[0024] In some implementations, the sensor can be a differential pressure sensor.

[0025] In some implementations, the sensor can be a microelectromechanical sensor.

[0026] In some implementations, the sensor can be a capacitive pressure sensor integrated on top of the CMOS readout circuitry.

[0027] In some implementations, the sensor can be a capacitive pressure sensor MEMS element coupled to a CMOS readout circuit.

[0028] In some embodiments, the system may further include an additional layer comprising a pattern of metallic wiring. A first conductive shielding layer may be positioned between the sensor and the additional layer. The first conductive shielding layer may define a pattern that overlaps with the pattern of the metallic wiring.

[0029] On the other hand, the host device includes a sensor. The sensor includes a substrate having a base electrode and a membrane suspended above the substrate. The membrane includes a membrane electrode. The membrane is configured to deflect relative to the base electrode in response to environmental conditions. The host device also includes electronic control equipment coupled to the base electrode and the membrane electrode. The electronic control equipment is operable to measure the capacitance between the base electrode and the membrane electrode and generate data indicating environmental conditions based on the measured capacitance. The host device also includes additional equipment operable to generate an electrical interference signal, and a conductive shielding layer positioned between the sensor and the additional equipment. The conductive shielding layer defines a plurality of holes extending through the conductive shielding layer. The host device also includes dielectric material disposed in the plurality of holes, one or more processors operable to receive data indicating environmental conditions from the electronic control equipment, and one or more display devices operable to present the data indicating environmental conditions to a user.

[0030] Implementations of this aspect may include one or more of the following features.

[0031] In some implementations, the host device can be a mobile device.

[0032] In some implementations, the host device can be at least one of a smartphone, tablet computer, or wearable device.

[0033] Details of one or more embodiments are set forth in the accompanying drawings and the following description. Other features and advantages will become apparent from the specification, the drawings, and the claims. Attached Figure Description

[0034] Figure 1A This is a schematic diagram showing a cross-sectional view of an example IC device.

[0035] Figure 1B It is shown Figure 1AThe diagram shows a schematic plan view of the IC device.

[0036] Figure 2 This is a graph showing an example of the sensor's output.

[0037] Figures 3A to 3C This is a schematic diagram showing a plan view of an example patterned shielding layer.

[0038] Figure 4A and Figure 4B This is a schematic diagram showing an additional example patterned shielding layer.

[0039] Figure 5A and Figure 5B This is a schematic diagram showing an additional example patterned shielding layer.

[0040] Figures 6A to 6C This is a schematic diagram showing an additional example patterned shielding layer.

[0041] Figures 7A to 7C This is a schematic diagram showing an additional example patterned shielding layer.

[0042] Figure 8 This is a schematic diagram showing a planar view of the CMOS back end.

[0043] Figure 9 This is a schematic diagram of an example host device that includes IC devices. Detailed Implementation

[0044] This article describes an example sensor with a temperature-stable sensor output.

[0045] In some embodiments, the integrated circuit (IC) device includes an integrated sensor for measuring characteristics of the environment. For example, the IC device can be fabricated by forming one or more patterned layers of material on top of a semiconductor wafer to define one or more electronic circuits (e.g., using a complementary metal-oxide-semiconductor [CMOS] fabrication process). Furthermore, a MEMS sensor can be fabricated on top of the IC device (e.g., on top of a CMOS “back end”) to measure environmental characteristics, generate an electrical signal based on the measurement, and provide the electrical signal to the IC device for further processing.

[0046] In some implementations, the integrated sensor can measure environmental characteristics based on capacitance changes between two electrodes. As an example, a pressure sensor can include a flexible membrane and an airtight, sealed cavity with a known atmospheric pressure (e.g., a reference pressure or gauge pressure) positioned on one side of the flexible membrane. The opposite side of the flexible membrane is exposed to the environment and is affected by the ambient atmospheric pressure. The flexible membrane deflects to varying degrees based on the pressure difference across its two sides. This degree of membrane deflection can be determined by measuring the capacitance between a measuring electrode embedded in the membrane and a base electrode positioned near the membrane (e.g., along the opposite side of the cavity). Based on this measurement, the sensor can determine the ambient pressure of the environment.

[0047] Since the sensor's output depends on the capacitance measured between the base electrode and the measuring electrode, electrical interference with the sensor can reduce the accuracy and / or reliability of its measurement results. For example, external electrical signals (e.g., signals generated by IC devices, such as clock signals) can capacitively couple to the sensor and change the capacitance reading between its electrodes. This interference can lead to erroneous measurement results from the sensor and increase noise in the sensor's output.

[0048] Such electrical interference can be reduced by including a shielding layer between the sensor and the source of electrical interference (e.g., other components of the IC device). As an example, the CMOS back-end can include a metal plate (e.g., an aluminum plate) positioned between the sensor and the source of electrical interference (e.g., a clock signal generator) in the IC device to minimize or reduce capacitive coupling between them.

[0049] However, including a large metal plate in the CMOS back-end can sometimes adversely affect the accuracy and / or reliability of the sensor during repeated temperature cycling. For example, temperature changes can cause plastic deformation in the metal plate, leading to cracks or breakage in the IC device. Furthermore, temperature changes can alter the mechanical stress of the metal plate and cause temperature-dependent output drift in the sensor (e.g., due to the sensor's sensitivity to mechanical stress). Additionally, the sensor output can exhibit temperature-dependent hysteresis (e.g., providing different measurement results depending on whether the sensor is heated or cooled).

[0050] Various techniques can be used to mitigate these effects. In some embodiments, sensor performance can be improved by reducing the amount of metal in the CMOS back-end undergoing plastic deformation. As an example, this can be achieved by reducing the amount of metal in the shielding plate (e.g., by patterning the shielding plate and / or reducing its thickness). As another example, mechanical stress in the shielding plate can be reduced so that it exhibits less plastic deformation in response to temperature changes (e.g., by patterning the shielding plate so that the dimensions of the remaining metal portions are on the same order of magnitude as the thickness of the shielding plate, thus reducing mechanical stress at the edges of the metal portions). As another example, the coefficient of thermal expansion of the shielding layer can be reduced to have lower thermally induced stress variations. As yet another example, certain materials that are not prone to temperature-induced plastic deformation (e.g., titanium, titanium nitride, or copper) can be used in the shielding plate. As yet another example, the IC device can be designed to minimize or reduce the use of certain materials (e.g., aluminum) near the sensor. Therefore, the sensor is shielded from electrical interference despite temperature changes, while its behavior is more stable and reliable.

[0051] Figure 1A A cross-sectional view of an example IC device 100 is shown. The IC device 100 includes a pressure sensor 150 formed on an integrated circuit 170. In some cases, the IC device 100 can be included in a host device, such as a mobile computing device (e.g., a smartphone, tablet, or wearable device).

[0052] In this example, integrated circuit 170 is a CMOS device and includes a passivation layer 172, a metallization layer 174, an intermetallic dielectric (IMD) layer 176, and one or more additional layers 178 (e.g., forming a fully fabricated CMOS wafer with one or more electronic circuits, such as a CMOS circuit or an application-specific integrated circuit [ASIC]). However, in practice, integrated circuit 170 can be any type of electronic device (e.g., a digital device, an analog device, a mixed-signal device, etc.).

[0053] Sensor 150 includes a substrate 152 defining a cavity 154 and a membrane 156 suspended above the cavity 154 (e.g., defining the upper wall of the cavity 154). The cavity 154 is hermetically sealed and has a known pressure P. 腔 (For example, reference pressure or gauge pressure). In some cases, P 腔 It can be essentially zero (e.g., vacuum) or some other known value. The opposite sides of the flexible membrane are exposed to the environment and subjected to the ambient atmospheric pressure P. 环境 .

[0054] Membrane 154 is flexible, and due to P 腔 With P 环境The pressure difference between them causes them to deflect. For example, if P 环境 Greater than P 腔 Then the membrane 156 will deflect towards the bottom of the cavity 154 (e.g., towards the integrated circuit 170 and effectively reduce the volume of the cavity 154). If P 环境 Less than P 腔 Then the membrane 156 will deflect away from the cavity 154 (e.g., away from the integrated circuit 170 and effectively increase the volume of the cavity 154).

[0055] The degree of deflection of membrane 156 is related to the pressure port P. 腔 With P 环境 This is related to the pressure difference between them. For example, a larger degree of deflection is related to P. 腔 and P 环境 The larger pressure difference between them is related to the smaller degree of deflection and P. 腔 and P 环境 It is related to the small pressure difference between them.

[0056] One or more capacitive sensors can be used to measure the degree of deflection. For example, sensor 150 can include one or more base electrodes 158 positioned along the bottom of cavity 154, and one or more measuring electrodes 160 positioned on or embedded in membrane 156. The capacitance C between base electrodes 158 and 160 depends on the distance between base electrodes 158 and measuring electrodes 160. Therefore, the degree of deflection of membrane 156 can be determined by measuring capacitance C.

[0057] Furthermore, the measured capacitance C can be used to determine P. 环境 For example, the measured capacitance C (corresponding to the degree of deflection of film 156) and P can be determined empirically. 腔 and P 环境 The relationship between the pressure differences (e.g., by applying a known pressure P) 腔 and P 环境 And determine the final degree of deflection of membrane 156). Subsequently, this relationship can be used (e.g., via IC devices and / or electronic control equipment 110) to determine the unknown P. 环境 (For example, by measuring the capacitance C and determining the capacitance at a given P) 腔 The corresponding P below 环境 ).

[0058] In some cases, electronic control device 110 can be used to process the measurement results from sensor 150. For example, electronic control device 110 can retrieve descriptions of the measured capacitances C and P. 环境 and P 腔The electronic control device 110 records data on known relationships between capacitances (e.g., in the form of one or more lookup tables, equations, calibration parameters, etc.). Furthermore, the electronic control device 110 is capable of receiving data indicating the measured capacitance C. Using this information, the electronic control device 110 can, given the measured capacitance C and the known capacitance P, perform calculations... 腔 Calculate P under the following circumstances 环境 .

[0059] In some cases, sensor 150 includes multiple sets of membranes, cavities, substrate electrodes, and measuring electrodes. This can be useful, for example, because it allows the sensor to acquire multiple different measurements simultaneously. In some cases, each set of membranes, cavities, substrate electrodes, and measuring electrodes can be similar to or substantially identical to each other. For example, sensor 150 can include a second set of membranes, cavities, substrate electrodes, and measuring electrodes positioned adjacent to membrane 160, cavity 154, substrate electrode 158, and measuring electrode 160 (e.g., from...). Figure 1A (Viewed from a cross-sectional angle, in a direction further away within the page).

[0060] The output of sensor 150 depends on the capacitance C measured between the base electrode 158 and the measuring electrode 154. Therefore, electrical interference to sensor 150 can reduce the accuracy and / or reliability of its measurement results. For example, an external electrical signal (e.g., a signal generated by integrated circuit 170, such as a clock signal) can capacitively couple to sensor 150 and change the capacitance reading between the base electrode 158 and the measuring electrode 160. This interference can lead to erroneous measurement results from sensor 150 and increase noise in the sensor's output.

[0061] This electrical interference can be reduced by including a conductive shielding layer between the sensor 150 and the source of electrical interference (e.g., other components of the IC device 100). For example, such as... Figure 1A As shown, the CMOS back-end can include a shielding layer 102 (e.g., a metal plate, such as an aluminum plate) positioned between the sensor 150 and electrical interference sources (e.g., circuitry in layer 178, such as a clock signal generator) in the IC device 100. Furthermore, the potential of the shielding layer 102 can be biased to the same potential as the base electrode 158. For example, this can help shield the sensor 150 from electrical interference from the integrated circuit 170 while minimizing or reducing parasitic capacitance caused by the shielding layer 102.

[0062] Figure 1B It shows Figure 1A The plan view of the IC device 100 shown includes a shielding layer 102. Figure 1B In the diagram, shielding layer 102 is depicted as a rectangular area with a brighter internal shadow, and the underlying integrated circuit 170 is depicted as a rectangular area with a darker surrounding shadow. For ease of illustration, [the text is incomplete and requires further context to translate accurately]. Figure 1BSensor 150 is omitted. However, the positions of membrane 156 and second membrane 164 (e.g., membranes from the second set of membranes, cavities, base electrodes, and measuring electrodes used to obtain the second pressure measurement result) are indicated by dashed lines. Figure 1A and Figure 1B In this configuration, the shielding layer 102 is positioned between the sensor 150 (including the base electrode and the measuring electrode) and the integrated circuit 170 to minimize or reduce electrical interference (e.g., capacitive coupling) between them.

[0063] However, the shielding layer 102 can sometimes adversely affect the accuracy and / or reliability of the sensor 150 during repeated temperature cycling. For example, temperature changes can cause plastic deformation in the shielding layer 102, leading to cracks or fractures in the IC device 100. Furthermore, temperature changes can alter the mechanical stress of the shielding layer 102 and can cause temperature-dependent output drift in the sensor 150 (e.g., due to the sensor's sensitivity to mechanical stress and / or displacement of the base electrode and measuring electrode).

[0064] Furthermore, the output of sensor 150 can exhibit temperature-dependent hysteresis. To illustrate, Figure 2 A graph 200 shows the total output sequence of 20 example sensors 150. Error bars represent the variation in output among the 20 sensors 150. In this example, a constant pressure is applied as P. 腔 and P 环境 The ambient temperature of sensor 150 cycles through a process of first increasing (e.g., from 40°C to 100°C), then decreasing (e.g., from 100°C to -40°C), and then increasing again (e.g., from -40°C to 20°C). Figure 2 As shown, the output of sensor 150 (e.g., as shown on the vertical axis) depends not only on the temperature of sensor 150, but also on the previous temperature state of sensor 150 (e.g., depending on whether the sensor is heated or cooled).

[0065] In some cases, these effects can be attributed to the use of aluminum in the IC device 100. For example, the upper metal layer at the back end of a CMOS device is sometimes made of aluminum, which has a relatively high coefficient of thermal expansion (e.g., approximately 20 × 10⁻⁶). -6 K -1 It also exhibits relatively low plastic yield strength (e.g., approximately 100 MPa) for compressive and tensile stresses. Furthermore, the yield strength of thin-film aluminum can vary significantly between different deposited films. The high coefficient of thermal expansion and low yield strength of aluminum can lead to plastic deformation in aluminum through temperature-induced stress changes. As an example, the temperature-induced mechanical stress σ can be estimated using the following equation:

[0066] σ = Young's modulus * (CTE)板 -CTE 衬底 Temperature changes

[0067] Among them, CTE 板 It is the coefficient of thermal expansion of the shielding material, while CTE 衬底 It is the coefficient of thermal expansion of the substrate material (e.g., laminate, carrier, and / or silicon chip). In some cases, the temperature-induced mechanical stress σ can be approximated by the following equation:

[0068] σ = Young's modulus * CTE 板 Temperature changes.

[0069] For example, assuming the Young's modulus of thin-film aluminum is approximately 70 GPa, it reaches its plastic yield strength at a temperature change of 70 K. Therefore, aluminum has already reached plastic deformation with relatively small temperature cycles. This deformation can lead to drift in integrated devices that are sensitive to changes in mechanical stress.

[0070] Various techniques can be used to mitigate these effects. In some embodiments, sensor performance can be improved by reducing the amount of metal in the CMOS back-end undergoing plastic deformation. As an example, this can be achieved by reducing the amount of metal in the shielding plate (e.g., by patterning the shielding plate and / or reducing its thickness). As another example, mechanical stress in the shielding plate can be reduced so that it exhibits less plastic deformation in response to temperature changes (e.g., by patterning the shielding plate so that the dimensions of the remaining metal portions are on the same order of magnitude as the thickness of the shielding plate, thus reducing mechanical stress at the edges of the metal portions). As yet another example, certain materials that are less prone to temperature-induced plastic deformation (e.g., titanium or titanium nitride) can be used in the shielding plate. As yet another example, the IC device can be designed to minimize or reduce the use of certain materials (e.g., aluminum) near the sensor. Therefore, the sensor is shielded from electrical interference despite temperature changes, while its behavior is more stable and reliable.

[0071] Figure 3A A plan view of an example IC device 100 with a patterned shielding layer 102 is shown. Figure 1B ,exist Figure 3A In the diagram, the shielding layer 102 is depicted as a rectangular area with a brighter internal shadow, and the underlying integrated circuit 170 is depicted as a rectangular area with a darker surrounding shadow. Similarly, for ease of illustration, [the text continues with further details about the shielding layer 102 and its depiction of the underlying integrated circuit 170]. Figure 3A Sensor 150 is omitted. However, the positions of membrane 156 and second membrane 164 are indicated by dashed lines.

[0072] In this example, films 156 and 164 are substantially rectangular in shape. For example, the length of each film 156 and 164 along the x-direction is greater than its width along the y-direction (e.g., according to a Cartesian coordinate system, where the x-direction is orthogonal to the y-direction). Furthermore, shielding layer 102 defines a plurality of holes 302 (e.g., grooves extending through shielding layer 102), each hole extending along the x-direction (e.g., such that the length of each hole 302 along the x-direction is greater than its width along the y-direction). The holes can be, for example, spaces in which there is no conductive material such as metal. One or more of the holes can be at least partially filled with a dielectric material (e.g., SiO2, undoped silicate glass [USG], phosphosilicate glass [PSG], fluorosilicate glass [FSG], high-density plasma [HDP] oxide, plasma-enhanced chemical vapor deposition [PECVD] SiN, PECVD SiO2, or other dielectric materials).

[0073] This configuration offers various benefits. For example, the rectangular membrane is primarily sensitive to stress in the direction of its short side (e.g., in the y-direction). Therefore, stress variations in the membrane due to plastic deformation of the shielding layer 102 can be mitigated by orthogonally oriented the holes (e.g., making the holes 302 extend in the x-direction). Furthermore, since the shielding layer 102 defines a plurality of holes 302 corresponding to areas without material, the amount of material used in the shielding layer 102 is reduced (e.g., compared to a shielding layer 102 without any holes). Thus, the patterned shielding layer 102 continues to mitigate the effects of electrical interference while reducing temperature-based hysteresis (e.g., by reducing the amount of material that is easily plastically deformable).

[0074] The density of the hole pattern can be varied relative to the shielding layer 102 depending on the implementation. For example, in Figure 3A In the example shown, the hole 302 occupies 15% of the total surface area of ​​the shielding layer 102. Therefore, 85% of the surface area of ​​the shielding layer 102 is a conductive material (e.g., a metal), while 15% of the surface area is a hole (e.g., a region lacking conductive material and at least partially filled with a dielectric material such as SiO2, undoped silicate glass [USG], phosphosilicate glass [PSG], fluorosilicate glass [FSG], high-density plasma [HDP] oxide, plasma-enhanced chemical vapor deposition [PECVD] SiN, PECVD SiO2, or other dielectric materials). These percentages can be varied depending on the implementation. For example, as... Figure 3BAs shown, the density of the hole pattern relative to the shielding layer 102 can be increased such that 60% of the surface area of ​​the shielding layer 102 is conductive material, while 40% of the surface area of ​​the shielding layer 102 is holes (e.g., to further reduce the amount of material used in the shielding layer 102). In some cases, the density of the hole pattern can be specified such that 10% to 50% of the surface area of ​​the shielding layer 102 is conductive material, while 50% to 90% of the surface area of ​​the shielding layer 102 is holes. In some cases, the density of the hole pattern can be specified such that 20% to 30% of the surface area of ​​the shielding layer 102 is conductive material, while 70% to 80% of the surface area of ​​the shielding layer 102 is holes. In fact, other percentages are also possible according to the embodiments.

[0075] The pattern of the holes 302 on the shielding layer 102 can also be changed depending on the implementation. In some cases, the holes 302 can be defined on the shielding layer 102 in a regular or repeating pattern. In some cases, the holes 302 can be defined on the shielding layer 102 in an irregular pattern (e.g., randomly or according to an arbitrary pattern). In some cases, the holes 302 can be arranged according to one or more rows and / or columns (e.g., some or all of the holes 302 can be aligned according to the x-direction and / or y-direction). As an example, such as Figure 3C As shown, the shielding layer 102 can define a series of uniformly spaced parallel holes 302 extending along the x-direction.

[0076] The dimensions of each hole 302 can also be varied depending on the implementation. In some cases, the length along the x-direction and / or the width along the y-direction of one or more holes 302 can differ from the length along the x-direction and / or the width along the y-direction of one or more other holes 302. In some cases, each hole in the holes 302 can have the same length along the x-direction and / or the same width along the y-direction. In some cases, the holes along their shorter dimensions (e.g., in...) Figures 3A to 3C The width of the hole (in the y-direction) can be less than three times its length along its longer dimension (e.g., in the x-direction). In some cases, the width of the hole along its shorter dimension can be less than twice its length along its longer dimension. In some cases, the width of the hole along its shorter dimension can be less than its length along its longer dimension. In some cases, the width of the hole along its shorter dimension can be 0.5 to 3 times its length along its longer dimension. In some cases, the thickness of the shielding layer 102 can be 0.8 μm or less (e.g., in the case of an aluminum shielding layer).

[0077] Furthermore, the width of the hole along its shorter dimension can be within the thickness of the hole (e.g., in...). Figures 3A to 3CThe width of the hole along its shorter dimension can be on the order of magnitude (in the z-direction). For example, the width of the hole along its shorter dimension can be approximately the same as the thickness of the hole. In some cases, the width of the hole along its shorter dimension can be 0.5 to 3 times the thickness of the shielding layer 102. In some cases, the thickness of the shielding layer 102 can be 0.8 μm or less (e.g., in the case of an aluminum shielding layer). Furthermore, if the width of the hole is oriented along the x-direction, the effect on stress changes in the pressure-sensitive membrane can be reduced.

[0078] exist Figures 3A to 3C In the example shown, the shielding layer 102 defines the holes in the form of parallel holes. However, other hole patterns can be used instead of or in addition to parallel holes. As an example, Figure 4A A plan view of an example IC device 100 with a patterned shielding layer 102 is shown. Figure 1B ,exist Figure 4A In the diagram, the shielding layer 102 is depicted as a rectangular area with a brighter internal shadow, and the underlying integrated circuit 170 is depicted as a rectangular area with a darker surrounding shadow. Similarly, for ease of illustration, [the text continues with further details about the shielding layer 102 and its depiction of the underlying integrated circuit 170]. Figure 4A Sensor 150 is omitted. However, the positions of membrane 156 and second membrane 164 are indicated by dashed lines.

[0079] In this example, shielding layer 102 defines a plurality of square or rectangular holes 402 extending through shielding layer 102. The holes 402 are arranged in a grid pattern (e.g., aligned with a series of rows and columns) and are vertically separated by horizontally extending lines 404 of material (e.g., metal) and horizontally separated by vertically extending lines 406 of material (e.g., metal). Each of lines 404 and 406 can be electrically coupled to each other (e.g., using conductive interconnects or vias positioned beneath shielding layer 102) such that they have substantially the same potential. In some cases, lines 404 and 406 can be biased such that they have substantially the same potential as the base electrode 158 of sensor 150. One or more of the holes in hole 402 can be at least partially filled with a dielectric material (e.g., SiO2, undoped silicate glass [USG], phosphosilicate glass [PSG], fluorosilicate glass [FSG], high-density plasma [HDP] oxide, plasma-enhanced chemical vapor deposition [PECVD] SiN, PECVD SiO2 or other dielectric materials).

[0080] Different grid pattern configurations can be used depending on the implementation. For example, the grid pattern can include holes 402 having any particular shape (e.g., square, rectangle, circle, ellipse, triangle, or any other shape). Furthermore, the grid pattern can include one or more holes whose shapes differ from those of one or more other holes. As another example, the dimensions of holes 402, lines 404, and / or lines 406 can vary depending on the implementation. For example, in some cases, lines 404 or 406 are positioned along their shorter dimension (e.g., respectively on...). Figures 4A to 4B In some cases, the width of line 404 or 406 along its shorter dimension can be less than twice the thickness of shielding layer 102. In some cases, the width of line 404 or 406 along its shorter dimension can be less than the thickness of shielding layer 102. In some cases, the width of hole along its shorter dimension can be less than the thickness of the hole (e.g., in the z direction). Figures 3A to 3C The width of line 404 or 406 along its shorter dimension can be 0.5 to 3 times the thickness of shielding layer 102. In some cases, the thickness of shielding layer 102 can be 0.8 μm or less (e.g., in the case of aluminum shielding).

[0081] Furthermore, the density of the hole pattern can be varied relative to the shielding layer 102 depending on the implementation. For example, in Figure 4A In the example shown, the aperture 402 occupies 60% of the total surface area of ​​the shielding layer 102. Therefore, 40% of the surface area of ​​the shielding layer 102 is a conductive material (e.g., metal), while 60% of the surface area of ​​the shielding layer 102 is the aperture. These percentages can be varied depending on the implementation. For example, as... Figure 4B As shown, the density of the hole pattern relative to the shielding layer 102 can be increased such that 20% of the surface area of ​​the shielding layer 102 is conductive material, while 80% of the surface area of ​​the shielding layer 102 is holes (e.g., to further reduce the amount of material used in the shielding layer 102). In some cases, the density of the hole pattern can be specified such that 10% to 50% of the surface area of ​​the shielding layer 102 is conductive material, while 50% to 90% of the surface area of ​​the shielding layer 102 is holes. In some cases, the density of the hole pattern can be specified such that 20% to 30% of the surface area of ​​the shielding layer 102 is conductive material, while 70% to 80% of the surface area of ​​the shielding layer 102 is holes. In fact, other percentages are also possible according to the embodiments.

[0082] Other patterns for the shielding layer 102 are also possible. For example, Figure 5A A portion of a patterned shielding layer 102 is shown, with the location of the film 156 indicated by dashed lines. For clarity, the same portion of the shielding layer 102 is shown in... Figure 5B The image shows the location of the cover without the cover film 156.

[0083] In this example, the shielding layer 102 includes a plurality of parallel horizontal shielding elements 502 extending in the x-direction (e.g., such that its length in the x-direction is greater than its width in the y-direction). Furthermore, the horizontal shielding elements 502 are interconnected by a plurality of parallel vertical shielding elements 504 extending in the y-direction (e.g., such that its width in the y-direction is greater than its length in the x-direction) to form a "brick"-like pattern of holes. Additionally, each of the horizontal shielding elements 504 defines one or more holes 506. In this configuration, each of the horizontal shielding elements 502 and 504 is interconnected with one or more other shielding elements to form a single conductive element having substantially the same potential overall. In some cases, the interconnected horizontal shielding elements 502 and vertical shielding elements 504 can be biased such that they have substantially the same potential as the base electrode 158 of the sensor 150. One or more of the holes 506 can be at least partially filled with a dielectric material (e.g., SiO2, undoped silicate glass [USG], phosphosilicate glass [PSG], fluorosilicate glass [FSG], high-density plasma [HDP] oxide, plasma-enhanced chemical vapor deposition [PECVD] SiN, PECVD SiO2 or other dielectric materials).

[0084] The dimensions of each horizontal shielding element 502 and vertical shielding element 504 can be varied depending on the implementation. For example, the length along the x-direction and / or the width along the y-direction of one or more of the horizontal shielding elements 502 and / or vertical shielding elements 504 can differ from the length along the x-direction and / or the width along the y-direction of the other horizontal shielding elements 502 and / or vertical shielding elements 504. As another example, each of the horizontal shielding elements 502 and / or vertical shielding elements 504 can have the same length along the x-direction and / or the same width along the y-direction. In some cases, the horizontal shielding element 502 may have a shorter dimension (e.g., in...) Figures 5A to 5B The width of the horizontal shielding element 502 (in the y-direction) can be less than three times the thickness of the shielding layer 102 (e.g., in the z-direction). In some cases, the width of the horizontal shielding element 502 along its shorter dimension can be less than twice the thickness of the shielding layer 102. In some cases, the width of the horizontal shielding element 502 along its shorter dimension can be less than the thickness of the shielding layer 102. In some cases, the width of the horizontal shielding element 502 along its shorter dimension can be 0.5 to 3 times the thickness of the shielding layer 102. In some cases, the thickness of the shielding layer 102 can be 0.8 μm or less (e.g., in the case of an aluminum shielding layer).

[0085] In some cases, the width of each horizontal shielding element 502 along the y-direction can be substantially smaller than its length along the x-direction. In some cases, the vertical spacing between adjacent horizontal shielding elements 502 (e.g., in the x-direction) can be 0.8 μm to 1 μm. This can be beneficial, for example, in suppressing viscoelastic relaxation of the shielding material in that direction. However, in some cases, the vertical spacing can be larger (e.g., 1 μm to 5 μm).

[0086] Furthermore, the density of the hole pattern relative to the shielding layer 102 can be varied depending on the embodiment. In some cases, the density of the hole pattern can be specified such that 10% to 50% of the surface area of ​​the shielding layer 102 is conductive material (e.g., horizontal and vertical shielding elements), while 50% to 90% of the surface area of ​​the shielding layer 102 is holes. In other cases, the density of the hole pattern can be specified such that 20% to 30% of the surface area of ​​the shielding layer 102 is conductive material, while 70% to 80% of the surface area of ​​the shielding layer 102 is holes. In fact, other percentages are also possible depending on the embodiment.

[0087] exist Figures 3A to 3C , Figures 4A to 4B and Figures 5A to 5B In the example, a single shielding layer 102 is used to reduce electrical interference to the sensor. However, in some cases, the device can include multiple shielding layers for reducing electrical interference to the sensor (e.g., one or more shielding layers stacked on top of each other in a stack). As an example, Figure 6A A plan view of an example first patterned shielding layer 602 is shown, and Figure 6B A plan view of an example second patterned shielding layer 604 is shown. Shielding layer 602 defines a pattern of holes 606 extending through shielding layer 602. Similarly, shielding layer 604 defines a pattern of holes 608 extending through shielding layer 604. One or more of holes 606 and / or 608 can be at least partially filled with a dielectric material (e.g., SiO2, undoped silicate glass [USG], phosphosilicate glass [PSG], fluorosilicate glass [FSG], high-density plasma [HDP] oxide, plasma-enhanced chemical vapor deposition [PECVD] SiN, PECVD SiO2, or other dielectric materials).

[0088] In some cases, each of two or more shielding layers can define its own distinct pattern for the aperture. For example, as... Figure 6A As shown, the pattern of hole 606 is different from that of hole 608. Therefore, when shielding layer 602 is stacked on top of shielding layer 604, holes 606 and 608 are misaligned (e.g., as shown). Figure 6CAs shown, a plan view of a shielding layer 602 stacked on top of a shielding layer 604 is illustrated, with the holes 608 of the lower shielding layer 604 shown in dashed lines.

[0089] As another example, Figure 7A A plan view of the example first patterned shielding layer 702 is shown, and Figure 7B A plan view of an example second patterned shielding layer 704 is shown. Shielding layer 702 defines a pattern of holes 706 extending through shielding layer 702 (e.g., horizontal holes), while shielding layer 704 defines a different pattern of holes 708 extending through shielding layer 704 (e.g., vertical holes). When shielding layer 702 is stacked on top of shielding layer 704, holes 706 and 708 are misaligned (e.g., as shown). Figure 7C The diagram shows a plan view of a shielding layer 702 stacked on top of a shielding layer 704, with holes 708 of the lower shielding layer 704 shown in dashed lines. One or more of holes 706 and / or 708 can be at least partially filled with a dielectric material (e.g., SiO2, undoped silicate glass [USG], phosphosilicate glass [PSG], fluorosilicate glass [FSG], high-density plasma [HDP] oxide, plasma-enhanced chemical vapor deposition [PECVD] SiN, PECVD SiO2, or other dielectric materials).

[0090] In some cases, each of two or more shielding layers defines a similar pattern of holes (e.g., a specific repeating pattern of holes). However, the pattern of holes on one shielding layer can be spatially offset relative to the pattern of holes on another shielding layer. For example, the pattern on one shielding layer can be spatially offset by a specific length in the x-direction relative to the pattern of another shielding layer (e.g., shifted in the x-direction) and / or spatially offset by a specific width in the y-direction (e.g., shifted in the y-direction).

[0091] although Figures 6A to 6C and 7A to Figure 7CThe combined use of two shielding layers is shown, but in practice, any number of shielding layers (e.g., one, two, three, four, or more) can be used in combination. Furthermore, in some cases, at least some of the shielding layers can define similar patterns of holes. Additionally, in some cases, at least some of the shielding layers can define different patterns of holes. In some cases, one or more shielding layers can be made of aluminum. In some cases, one or more shielding layers can be made of aluminum doped with a dopant material. As an example, the shielding layer can be doped with a certain amount of copper (e.g., about 1 wt% copper) to improve mechanical strength and reduce electromigration. As other examples, one or more shielding layers can include aluminum doped with strontium and / or praseodymium, alone or in combination with copper, to improve the yield strength of the shielding layer.

[0092] In some cases, one or more shielding layers can be made of a conductive material that is less susceptible to temperature-induced plastic deformation compared to aluminum. For example, one or more shielding layers can be made of titanium, titanium nitride, and / or copper. However, in other cases, one or more shielding layers can be made of aluminum.

[0093] Other modifications can be made to the IC device to improve the sensor's performance and stability, and reduce temperature-related noise and hysteresis.

[0094] In some cases, to further reduce the influence of aluminum in the CMOS back-end, the CMOS back-end can be configured to minimize or reduce the amount of metal parallel to the stress-sensitive direction of the film (e.g., in the y-direction). For example, relatively large metal material lines (e.g., power rails) can be repositioned as much as possible so that they are not parallel to the stress-sensitive direction of the film (e.g., so that they extend instead in the x-direction). Furthermore, if the metal layers are positioned along the stress-sensitive direction of the film, they can be fabricated to reduce their width. Additionally, these components can be placed in lower layers of the integrated circuit (e.g., because these components are typically thinner in lower layers than in higher metal layers). As an example, Figure 8 A plan view of an example CMOS back-end 800 comprising two adjacent metal layers N-1 and N-2 is shown. For reference, the positions of the first film 156 and the second film 164 are indicated by dashed lines. Furthermore, for ease of illustration, each layer in the CMOS back-end 800 is shown as a transparent layer, except for power rail 802a on metal layer N-1 and power rail 802b on metal layer N-2 (e.g., to illustrate the position of the power rails relative to each other). Figure 8 As shown, each of the power rails 802a and 802b is parallel to the stress-insensitive direction of the membrane (e.g., parallel to the x-direction).

[0095] While various features related to pressure sensors are described in this article, these are merely illustrative examples. In practice, these features can be implemented in any type of stress-sensitive MEMS structure, such as absolute pressure sensors, gauge pressure sensors, differential pressure sensors, gyroscopes, accelerometers, microphones, etc. Furthermore, these features can be implemented in any stress-sensitive transducer integrated on top of a CMOS device, a standalone stress-sensitive transducer with an embedded shielding plate below the sensor area, or a stress-sensitive transducer directly bonded to a wafer with readout electronics.

[0096] Example System

[0097] Some embodiments of the subject matter and operation described in this specification can be implemented using digital electronic circuits or computer software, firmware, or hardware, or a combination thereof, including the structures disclosed herein and their equivalents. For example, in some embodiments, one or more components of the electronic control device 110 can be implemented using digital electronic circuits, or using computer software, firmware, or hardware, or a combination thereof.

[0098] Some of the embodiments described in this specification can be implemented as one or more groups or modules of digital electronic circuits, computer software, firmware, or hardware, or a combination thereof. Although different modules can be used, each module need not be different, and multiple modules can be implemented on the same digital electronic circuits, computer software, firmware, or hardware, or a combination thereof.

[0099] Some embodiments described in this specification can be implemented as one or more computer programs, i.e., one or more modules of computer program instructions, which are encoded on a computer storage medium for execution or control of its operation by a data processing apparatus. The computer storage medium can be or can be included in a computer-readable storage device, a computer-readable storage substrate, a random or serial access storage array or device, or a combination thereof. Furthermore, although the computer storage medium is not a propagating signal, it can be a source or destination of computer program instructions encoded as artificially generated propagating signals. The computer storage medium can also be one or more separate physical components or media (e.g., multiple CDs, disks, or other storage devices) or included therein.

[0100] The term "data processing apparatus" encompasses all kinds of devices, apparatuses, and machines for processing data, including, for example, programmable processors, computers, systems-on-a-chip, or a combination thereof. The apparatus may include special-purpose logic circuitry, such as FPGAs (Field-Programmable Gate Arrays) or ASICs (Application-Specific Integrated Circuits). In addition to hardware, the apparatus may also include code that creates an execution environment for the computer program, such as code constituting processor firmware, protocol stacks, database management systems, operating systems, cross-platform runtime environments, virtual machines, or one or more combinations thereof. The apparatus and execution environment can implement various different computing model infrastructures, such as web services, distributed computing, and grid computing infrastructures.

[0101] Computer programs (also known as programs, software, software applications or "apps", scripts or code) can be written in any form of programming language, including compiled or interpreted languages, declarative or procedural languages. A computer program may, but does not necessarily, correspond to a file in a file system. A program can be stored as a part of a file containing other programs or data (e.g., stored in one or more scripts in a markup language document), a single file dedicated to said program, or multiple coordination files (e.g., a file storing one or more modules, subroutines, or portions of code). Computer programs can be deployed to execute on one or more computers located at a single site or distributed across multiple sites and interconnected via a communication network.

[0102] Some of the processing and logic flows described in this specification can be executed by one or more programmable processors that execute one or more computer programs to perform operations by manipulating input data and generating outputs. The processing and logic flows can also be executed by dedicated logic circuits, and the device can also be implemented as dedicated logic circuits, such as FPGAs (Field-Programmable Gate Arrays) or ASICs (Application-Specific Integrated Circuits).

[0103] Processors suitable for executing computer programs include, for example, general-purpose microprocessors and special-purpose microprocessors, as well as processors of any type of digital computer. Typically, the processor receives instructions and data from read-only memory or random access memory, or both. A computer includes a processor for performing operations according to instructions and one or more memory devices for storing instructions and data. A computer may also include, or be operatively coupled to, receiving data from, or transferring data to, one or more mass storage devices for storing data, or both, such mass storage devices as magnetic disks, magneto-optical disks, or optical disks. However, a computer need not have such devices. Devices suitable for storing computer program instructions and data include all forms of non-volatile memory, media, and memory devices, including, for example, semiconductor memory devices (e.g., EPROM, EEPROM, flash memory devices, etc.), magnetic disks (e.g., internal hard disks, removable disks, etc.), magneto-optical disks, and CD-ROMs and DVD-ROMs. The processor and memory can be complemented or incorporated into dedicated logic circuitry.

[0104] To provide interaction with the user, operation can be performed on a computer having a display device (e.g., a monitor or another type of display device) for displaying information to the user and a keyboard and pointing device (e.g., a mouse, trackball, tablet, touchscreen, or another type of pointing device) that the user can use to provide input to the computer. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback, such as visual feedback, auditory feedback, or tactile feedback; and input from the user can be received in any form, including sound input, voice input, visual input, or tactile input. Furthermore, the computer can interact with the user by sending documents to or receiving documents from the device used by the user; for example, by sending a webpage to a web browser on the user's client device in response to a request received from a web browser.

[0105] A computer system may include a single computing device or multiple computers that operate in proximity or generally remotely to each other and typically interact via a communication network. Examples of communication networks include local area networks (“LANs”) and wide area networks (“WANs”), the Internet (e.g., the Internet), networks including satellite links, and peer-to-peer networks (e.g., ad hoc peer-to-peer networks). A client-server relationship can be created by computer programs running on their respective computers and having a client-server relationship with each other.

[0106] The IC devices described herein can be integrated into host devices such as smartphones, laptops, wearable devices, other computers, and automobiles. The host device may include processors and other electronic components, as well as other supplementary modules configured to collect data (e.g., cameras, time-of-flight imagers, etc.). Other supplementary modules may be included, such as ambient lighting, displays, automotive headlights, etc. The host device may also include non-volatile memory storing instructions for operating the IC device and, in some cases, operating the supplementary modules.

[0107] Components and supplementary modules integrated into the host device can generate electrical signals that may interfere with the operation of capacitive sensors. Furthermore, these components and supplementary modules can generate significant heat, increasing the sensor's operating temperature. Additionally, the host device must withstand a wide range of environmental conditions, including a diverse range of ambient temperatures.

[0108] IC devices possessing one or more of the features described herein offer significant advantages in this implementation. For example, shielding the IC device's sensor from electrical interference through a patterned shielding layer improves the accuracy and / or reliability of the sensor's measurements. Furthermore, the measurements are less susceptible to temperature variations. This can provide substantial advantages to the host device in which these IC devices are implemented. For instance, in some cases, the IC device includes a pressure sensor and is integrated into a smartphone. Since the pressure data collected by these sensors is temperature-invariant, and the pressure data is used for functions performed by the smartphone (e.g., determining the smartphone's altitude), these functions are also likely to be temperature-invariant, thus providing substantial advantages to the smartphone itself.

[0109] As an example, Figure 9A host device 900 is shown, comprising an IC device 100 (including a sensor 150 and an integrated circuit 170 with a patterned shielding layer 102). The host device 900 also includes multiple additional components, including one or more computer processors 910 (e.g., to implement electronic control device 110), one or more displays 920, one or more power supplies 930 (e.g., batteries, charging circuits, etc.), and one or more transceivers 940 (e.g., radios, such as Wi-Fi radio, cellular radio, Bluetooth radio, etc.). During operation of the host device 900, the computer processors 910, displays 920, power supplies 930, and transceivers 940 can each generate significant amounts of heat. Furthermore, the environment surrounding the host device 900 (e.g., sunlight, ambient air, the user's body, etc.) can also transfer additional heat to the host device 900. However, due to the patterned shielding layer 102, the output of the sensor 105 is less susceptible to temperature-related drift and hysteresis, and is therefore more accurate and reliable under a variety of different operating conditions (e.g., compared to the host device 900 without the patterned shielding layer 102).

[0110] Although this specification contains numerous details, these details should not be construed as limiting the scope of claims, but rather as descriptions of specific features of particular examples. Some features described in the context of individual embodiments in this specification can also be combined. Conversely, various features described in the context of a single embodiment can also be implemented individually or in any suitable sub-combination in multiple embodiments.

[0111] Several embodiments have been described. However, various modifications can be made without departing from the spirit and scope of the invention. Therefore, other embodiments are within the scope of the claims.

Claims

1. A system comprising: Sensor (150), comprising: A substrate, comprising a substrate electrode; and A first membrane (156) is suspended above the substrate, wherein the first membrane (156) includes a first membrane electrode, and wherein the first membrane (156) is configured to deflect relative to the substrate electrode (158) in response to environmental conditions. The sensor (150) is operable to measure the capacitance between the substrate electrode (158) and the first membrane electrode; A first conductive shielding layer (102) is positioned between the sensor (150) and a device operable by the system to generate an electrical interference signal, wherein the first conductive shielding layer (102) defines a plurality of first holes (302) extending through the first conductive shielding layer (102); and Dielectric material disposed in the plurality of first holes (302), in, The length of the first membrane (156) in the first direction is greater than the length of the first membrane (156) in the second direction orthogonal to the first direction, and The length of each of the plurality of first holes (302) in the first direction is greater than the length of the first hole (302) in the second direction.

2. The system according to claim 1, wherein, The first conductive shielding layer (102) includes a plurality of conductive elements arranged in a grid. The plurality of conductive elements are electrically interconnected with each other.

3. The system according to claim 1 further includes a second conductive shielding layer (602) positioned between the sensor (150) and the auxiliary device, wherein, The second conductive shielding layer (602) defines a plurality of second holes (606) extending through the second conductive shielding layer, wherein a dielectric material is disposed in the plurality of second holes (606).

4. The system according to claim 3, wherein, The plurality of first holes (302) define a first pattern relative to the first conductive shielding layer, and wherein the plurality of second holes (606) define a second pattern relative to the second conductive shielding layer (602), the second pattern being different from the first pattern.

5. The system according to claim 3, wherein, The plurality of first holes (302) define a first pattern relative to the first conductive shielding layer, wherein the plurality of second holes (606) define a second pattern relative to the second conductive shielding layer (602), at least a portion of the first portion being geometrically similar to at least a portion of the second portion, and the second pattern being spatially offset from the first pattern.

6. The system according to claim 1, wherein, The first conductive shielding layer (102) includes a plurality of parallel first conductive segments, wherein the first conductive segments are electrically interconnected by a plurality of parallel second conductive segments perpendicular to the plurality of first conductive segments.

7. The system according to claim 6, wherein, The length of the first membrane (156) in the first direction is greater than the length of the first membrane in the second direction orthogonal to the first direction, and Wherein, the length of each of the plurality of first conductive segments in the first direction is greater than the length of the first conductive segment in the second direction.

8. The system according to claim 7, wherein, The length of each of the plurality of first conductive segments in the second direction is less than three times the thickness of the first conductive shielding layer (102) in a third direction orthogonal to the first and second directions.

9. The system according to claim 7, wherein, The length of each of the plurality of first conductive segments in the second direction is less than the thickness of the first conductive shielding layer in a third direction orthogonal to the first and second directions.

10. The system according to claim 1, wherein, In cross-section, the area of ​​the plurality of first holes is 40% to 90% of the total area of ​​the plurality of first conductive shielding layers.

11. The system according to claim 1, wherein, The thickness of the first conductive shielding layer is less than 0.8 μm.

12. The system according to claim 1, wherein, The first conductive shielding layer comprises aluminum and a doped material. The doping material is at least one of copper, scandium, or praseodymium.

13. The system according to claim 1, wherein, The first conductive shielding layer includes at least one of titanium, titanium nitride, or copper.

14. The system according to claim 1, wherein, The first conductive shielding layer is positioned between the sensor and a plurality of devices operable to generate an electrical interference signal, wherein the sensor is operable to shut down at least one of the plurality of devices when measuring the capacitance between the base electrode and the first film electrode.

15. The system according to claim 1, wherein, The environmental conditions refer to the pressure in the environment of the system.

16. The system according to claim 1, wherein, The first membrane and the substrate define a first cavity.

17. The system according to claim 1, wherein, The sensor is a differential pressure sensor.

18. The system according to claim 1, wherein, The sensor is a capacitive pressure sensor integrated on top of the CMOS readout circuit.

19. The system according to claim 1, wherein, The sensor is a capacitive pressure sensor MEMS element coupled to a CMOS readout circuit.

20. The system of claim 1, further comprising an additional layer, the additional layer comprising a pattern of metal wiring; in, The first conductive shielding layer is positioned between the sensor and the additional layer; and The first conductive shielding layer defines a pattern that overlaps with the pattern of the metal wiring.

21. The system according to claim 1, wherein, The first hole (302) is defined by a regular pattern.

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