STRAIN SENSING FILM, PRESSURE SENSOR AND HYBRID STRAIN SENSING SYSTEM

FIELD

The present application relates to the field of semiconductor thin-film technology, and in particular, to a strain sensing film, a pressure sensor, and a hybrid strain sensing system.

BACKGROUND

At present, pressure sensors include such as resistor strain gauge type, capacitance induction type, and piezoelectric ceramic type. These types of pressure sensors are all formed by complex circuit design and structural design to form the pressure sensor itself. For example, for the resistor strain gauge type, it is necessary to select strain gauges that meet requirements of resistors and deviations from many well-produced strain gauges, meanwhile, the strain gauges are combined to form a certain circuit structure, the colloid is used to connect a sensing structure, and the deformation of the strain gauge under pressure is low, so the sensing structure needs to be precisely positioned and carefully bonded. The capacitance induction type needs to strictly control a distance between each capacitive point and a panel, pressure information is obtained through a changing of the distance, so an extremely high accuracy on processing and assembly for the manufacturing process is required. For the piezoelectric ceramic type, the pressure is acquired based on a short-term voltage variation obtained by instantaneous impact on the piezoelectric ceramic. The production of this type of pressure sensors requires a uniform and consistent piezoelectric ceramic piece, and needs to be installed on a particular structure through a special installation method.

However, the manufacturing process of existing pressure sensors has the problem of high practical cost, which brings difficulties to the large-scale promotion of pressure sensing. In particular, these pressure sensors have low resistance to external environmental disturbances. Under external conditions such as temperature variations, the pressure sensors will be affected, resulting in inaccurate pressure measurement.

SUMMARY

An objective of the embodiments of the present application is intended to, but not limited to, improve the sensitivity and accuracy of pressure measurement during production and use, and enhance resistance to external environmental disturbances, by providing a strain sensing film, a pressure sensor, and a hybrid strain sensing system.

To solve the above problem, solutions provided by the embodiments of the present application are as follows.

In accordance with a first aspect of the present application, a strain sensing film is provided, which includes: a semiconductor thin-film, at least two resistors are disposed on the semiconductor thin-film, one resistor has a different response to a strain with respect to at least another resistor.

In one embodiment, the semiconductor thin-film includes at least one of a silicon (Si) thin-film, a germanium (Ge) thin-film, a gallium arsenide (GaAs) thin-film, and a gallium nitride (GaN) thin-film, a silicon carbide (SiC) thin-film, a zinc sulfide (ZnS) thin-film, or a zinc oxide (ZnO) thin-film.

In one embodiment, the one resistor has a different gauge factor with respect to the at least another resistor.

In one embodiment, the one resistor is arranged in a different orientation with respect to the at least another resistor.

In one embodiment, the one resistor is oriented in a direction perpendicular to the at least another resistor.

In one embodiment, a Wheatstone bridge is arranged on the semiconductor thin-film, and the Wheatstone bridge includes a first resistor, a second resistor, a third resistor, and a fourth resistor. The second resistor and the third resistor have positive gauge factors, and the first resistor and the fourth resistor have negative gauge factors.

In one embodiment, dR2/R2=GF2×∈, dR1/R1=GF1×∈, a voltage signal of the Wheatstone bridge dU=Vcc/2×(dR2/R2−dR1/R1)=Vcc×GF1×∈, where GF2 is a pressure-inductance coefficient of a second resistor, GF1 is a pressure-inductance coefficient of a first resistor, GF1=−GF2, ∈ is a strain at the Wheatstone bridge, and Vcc is a voltage supplied to the Wheatstone bridge.

In one embodiment, a temperature sensor is provided in the semiconductor thin-film.

In one embodiment, the strain sensing film is also provided with a signal processing circuit. The signal processing circuit is configured to receive a temperature detection signal output by the temperature sensor, and determine a sensor correction sensitivity according to a preset correlation table of the effective gauge factor versus temperature.

In one embodiment, the thickness of the semiconductor thin-film is less than or equal to 70 μm.

In one embodiment, the thickness of the semiconductor thin-film is less than or equal to 50 μm.

In one embodiment, the thickness of the semiconductor thin-film is less than or equal to 30 μm.

In one embodiment, the thickness of the semiconductor thin-film is less than or equal to 25 μm.

In one embodiment, the thickness of the semiconductor thin-film is less than or equal to 20 μm.

In one embodiment, the thickness of the semiconductor thin-film is less than or equal to 15 μm.

In accordance with a second aspect of the present application, a pressure sensor is provided. The pressure sensor includes a substrate, and at least one side surface of the substrate is provided with the strain sensing film according to any one of the above.

In accordance with a third aspect of the present application, a hybrid strain sensing system is provided. The hybrid strain sensing system includes: a substrate; a signal processing circuit; and the strain sensing film according to any one of the above. The strain sensing film is attached to the substrate, and the strain sensing film is in connection with the signal processing circuit.

Embodiments of the present application provide a strain sensing film, a pressure sensor, and a hybrid strain sensing system. The strain sensing film includes a semiconductor thin-film, and at least two resistors are disposed on the semiconductor thin-film, one resistor and at least another resistor respond differently to a strain, thereby enhancing resistance to external environmental disturbances and improving the accuracy of pressure measurements.

BRIEF DESCRIPTION OF DRAWINGS

In order to explain the solutions in embodiments of the present application more clearly, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the existing technologies. Obviously, the drawings in the following description are merely some embodiments of the present application, and for persons skilled in the art other drawings may also be obtained on the basis of these drawings without creative labor.

FIG. 1 shows an exemplary strain sensing film deposited on a substrate to form a variable resistor in accordance with an embodiment of the present application;

FIG. 2 shows an exemplary strain sensing film deposited on a substrate to which a force is applied, in accordance with an embodiment of the present application;

FIG. 3 shows an exemplary Wheatstone bridge, in which one arm R1 of the bridge is replaced by a piezoresistive resistor, and R2, R3, R4 are reference resistors, in accordance with an embodiment of the present application;

FIG. 4 shows eight exemplary illustrative arrangements of resistors on a strain sensing film for one embodiment of the present application;

FIG. 5 is a schematic diagram of a strain sensing film in accordance with an embodiment of the present application; and

FIG. 6 is a schematic diagram of a pressure sensor in accordance with an embodiment of the present application.

DETAILED DESCRIPTION

In order to make the objectives, solutions and beneficial effects of the present application more comprehensible, the present application will be described in further detail below with reference to the drawings and embodiments. It should be understood that specific embodiments described herein are intended only to interpret the present application, and are not intended to limit the present application.

It should be noted that when a component is referred to as being “fixed to” or “disposed on” another component, it can be directly or indirectly on the other component. When an element is referred to as being “connected to” another element, it can be directly or indirectly connected to the other element. The orientation or positional relationship indicated by terms “upper”, “lower”, “left”, “right”, etc. is based on the orientation or positional relationship shown in the drawings, and is used only for the convenience of description, rather than indicating or implying the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation to the present application, for those of ordinary skill in the art the specific meanings of the above terms can be understood according to specific situations. The terms “first” and “second” are only used for the purpose of description, and should not be understood as indicating or implying relative importance or implicitly indicating the number of features. The phrase “a/the plurality of” means two or more, unless expressly specified otherwise.

The temperature coefficient of resistance (TCR) represents a relative variation of resistance value when the temperature varies by 1° C., and the unit is ppm/° C. (i.e., 10⁻⁶/° C.). The gauge factor (GF) of the resistance strain gauge represents a relative variation of the strain gauge resistance caused by a unit strain of the resistance strain gauge, where dR/R=GF×∈, dR/R is a resistance-variation rate, and c is a mechanical strain of the material. An effective gauge factor (GF_eff) is a ratio of an actual resistance variation to an ideal strain assuming that the semiconductor thin-film has no effect on the structural strength. For a specific structure, a deformation of the structure is determined when a certain external force is applied, while when a semiconductor thin-film having a large elastic modulus such as silicon (Si) is attached to the structure, the deformation of Si is generally smaller than the deformation of the carrier structure. As the thickness of the film increases, the strain deformation at the film becomes smaller, and corresponding the resistance variation decreases, that is, the effective GF decreases with the increase of the thickness of the film.

In accordance with an embodiment of the present application, a strain sensing film is provided, which includes a semiconductor thin-film, and on the semiconductor thin-film, at least two resistors are disposed, one resistor and at least another resistor have different responses to a strain.

In this embodiment, the at least two resistors on the semiconductor thin-film have different responses to a strain may be achieved by arranging two resistors to have different thicknesses, different placement positions, different preparation materials, and different resistor shapes.

Further, one resistor has a different gauge factor with respect to the at least another resistor.

Since the gauge factor of one resistor is different from that of the at least another resistor on the semiconductor thin-film, at least two different electrical signals are generated in two resistors, or at least two resistance values are simultaneously generated, during a strain-sensing process. Thereby the sensitivity of the semiconductor thin-film is increased, and thus an accurate strain signal can be detected even in small-strain circumstances.

In one of the embodiments, at least two resistors are arranged in different orientations, or at least two resistors are made of different piezoresistive materials, or at least two resistors have different thicknesses, so that the gauge factor of one resistor is different from that of the at least another resistor on the semiconductor thin-film.

The main types of strain sensors are based on piezoresistive strain gauges or their variants. In case that piezoresistive materials are used in the strain gauges, the conductivity or resistivity varies when the material is under stress. In one common form of such strain gauges, a thin-film of piezoresistive material is deposited or attached or bonded to a substrate to form a variable resistor. FIG. 1 shows an exemplary strain sensing film deposited on a substrate to form a variable resistor, where the deposition manner may be gluing, mechanical fixation, surface mount (SMT), and so on. After the variable resistor is formed on the substrate, electrical contact is made to measure the resistance value R_G0. For the purpose of demonstration, FIG. 1 shows two mechanical supports 101. It should be understood that other design of the support structure may also be used as long as the structure can predictably and repeatably translate the applied force into localized strain. FIG. 2 shows an exemplary strain sensing film 20 deposited on the substrate 10 when a force is applied to the substrate, and the resistance value in the structure now becomes R_G1, as shown in FIG. 2, any deformation of the substrate will cause a variation in resistance value of a variable resistor R1, and the strain or force can be calculated based on a measurement of the variation in resistance value (for example, the variation in resistance value is measured through the Wheatstone bridge structure shown in FIG. 3). The deformation of the substrate may also be measured using a half bridge, as shown in FIG. 3, where R1 is the variable resistor.

Referring to FIG. 4, the strain sensing film is a semiconductor thin-film 201 having a (100) crystallographic orientation, and at least two resistors 202 are disposed on the semiconductor tin film 201, one resistor and at least another resistor are arranged in different orientations.

In one of the embodiments, the semiconductor thin-film 201 includes at least one of a silicon (Si) thin-film, a germanium (Ge) thin-film, a gallium arsenide (GaAs) thin-film, a gallium nitride (GaN) thin-film, a silicon carbide (SiC) thin-film, a zinc sulfide (ZnS) thin-film, or a zinc oxide (ZnO) thin-film.

In one of the embodiments, one resistor is oriented in a direction perpendicular to the at least another resistor.

For p-type doped (100) crystalline silicon materials, the gauge factors at two mutually perpendicular orientations are basically the same in magnitude and opposite in sign, while the TCR has little correlation with orientations. Thus, the signal quantity output by the strain sensing film under the same deformation can be enhanced, by arranging two mutually perpendicular resistors on the same semiconductor thin-film, and the influence of the ambient temperature on the signal quantity can be reduced.

Referring to FIG. 4, 201 represents the semiconductor thin-film on which the resistors are disposed, (that is not drawn to scale of the actual semiconductor thin-film). 202 represents the resistor deposited on the semiconductor thin-film. The rectangular shape of the resistor shown in FIG. 4 does not represent the actual shape of the resistor, but is used to indicate the direction of current flow, the current flows parallel to the long sides of the rectangle. Actual resistors may contain different aspect ratios, the actual resistors may even be a combination of multiple sections, each section has its own aspect ratio. Again, the location of each resistor is illustrative and may not be their actual location, as is the case for all configurations in FIG. 4. FIG. 4A to FIG. 4H only show the orientation relationship of the resistors, not their positions.

In FIG. 4A, four resistors are disposed on the semiconductor thin-film 201, and each resistor is perpendicular to the other two resistors.

FIG. 4B may represent the same configuration of FIG. 4A, as FIG. 4A and FIG. 4B both include four resistors, each resistor is perpendicular to the other two resistors, and each resistor is parallel to at least one side of the semiconductor thin-film 201.

In FIG. 4C, four resistors are disposed on the semiconductor thin-film 201, each resistor is perpendicular to the other two resistors, and each resistor is arranged at an angle of 45 degrees with respect to at least one side of the semiconductor thin-film 201.

In FIG. 4D, four resistors are disposed on the semiconductor thin-film 201, and the four resistors are arranged in parallel with each other.

In one embodiment, the four resistors in FIG. 4D are arranged in parallel.

In FIG. 4E, two resistors are disposed on the semiconductor thin-film 201, and the two resistors are arranged perpendicular to each other.

In FIG. 4F, two resistors are disposed on the semiconductor thin-film 201, and the two resistors are arranged in parallel with each other.

In one embodiment, the two resistors in FIG. 4F are arranged in parallel.

In FIG. 4G, three resistors are disposed on the semiconductor thin-film 201, and an angle formed between two adjacent resistors is 45 degrees.

In FIG. 4H, three resistors are disposed on the semiconductor thin-film 201, and an angle formed between two adjacent resistors is 60 degrees, or 120 degrees.

In this embodiment, one resistor is arranged in a different orientation with respect to at least another resistor, due to the anisotropy of the semiconductor material, the gauge factors in the two orientations are different, and thus at least two different electrical signals are generated in two resistors, or at least two resistance values are simultaneously generated, during the strain-sensing process. To be specific, in the embodiments of the present application, the “orientation” of the resistor refers to the direction of the current flowing through the resistor, rather than the geometric shape of the resistor.

Referring to FIG. 4, the semiconductor thin-film 201 may include two resistors forming a half-Wheatstone bridge, and the gauge factor of one resistor may be different from the gauge factor of the other resistor.

In one embodiment, the semiconductor thin-film 201 may include two resistors forming a half-Wheatstone bridge, and a strain level of one resistor in a sensing device may be different from the strain level of the other resistor in the strain sensing device.

In one embodiment, the direction of current flow in at least one resistor is perpendicular to the direction of current flow in at least another resistor.

In this embodiment, the semiconductor thin-film 201 may include two resistors forming a half-Wheatstone bridge, and among the two resistors forming the half-Wheatstone bridge, the direction of current flow in one resistor may be perpendicular to the direction of current flow in the other resistor.

In one embodiment, the direction of current flow in at least one resistor is perpendicular to the direction of current flow in at least another resistor.

In one embodiment, the Wheatstone bridge is provided on the semiconductor thin-film, and the Wheatstone bridge includes a first resistor, a second resistor, a third resistor and a fourth resistor. The second and third resistors have positive gauge factors, and the first and fourth resistors have negative gauge factors.

In this embodiment, as shown in FIG. 5, the strain sensing film is a semiconductor thin-film 201 having a (100) crystallographic orientation. On semiconductor thin-film 201, a first resistor R1, a second resistor R2, a third resistor R3, and a fourth resistor R4 are arranged. For the p-type doped (100) crystalline silicon material, the gauge factors at two mutually perpendicular orientations are basically the same in size and opposite in sign, while the TCR has little correlation with orientations. Thus, by arranging the second resistor R2 and the first resistor R1 to be perpendicular to each other, and arranging the third resistor R3 and the fourth resistor R4 to be perpendicular to each other, two resistors have positive gauge factors, and two resistors have negative gauge factors are arranged on one semiconductor thin-film, thereby the signal quantity output from the Wheatstone bridge under the same deformation can be enhanced, and the influence of the ambient temperature on the signal quantity can be reduced.

In one embodiment, dR2/R2=GF2×∈, dR1/R1=GF1×∈, the voltage signal of Wheatstone bridge dU=Vcc/2×(dR2/R2−dR1/R1)=Vcc×dR2/R2, GF2 is a pressure-inductance coefficient of the second resistor R2, GF1 is a pressure-inductance coefficient of the first resistor R1, GF1=−GF2, where ∈ is the strain at the Wheatstone bridge, and Vcc is a voltage supplied to the Wheatstone bridge.

In this embodiment, four resistors are arranged on the semiconductor thin-film 201, and the signal quantity output from the Wheatstone bridge under the same deformation can be significantly enhanced by adjusting the angles of the four resistors. For example, the second and third resistors are arranged to have positive gauge factors, the first and fourth resistors are arranged to have negative gauge factors, at this time, under the same deformation, dR2/R2=−dR1/R1, the voltage signal of the Wheatstone bridge dU=Vcc/2×(dR2/R2−dR1/R1)=Vcc×dR2/R2.

In one embodiment, the semiconductor thin-film 201 is provided with a temperature sensor.

In this embodiment, the temperature variation in a deformation region can be accurately measured through the temperature sensor built in the semiconductor thin-film 201, so that the resistance variation caused by the temperature variation in the deformation region can be compensated more accurate, thereby avoiding measurement error caused by the external temperature sensor being unable to measure the exact temperature of the semiconductor thin-film 201.

In one of the embodiments, the semiconductor thin-film 201 is also provided with a signal processing circuit, and the signal processing circuit is configured to receive a temperature detection signal output by the temperature sensor, and determine a sensor correction sensitivity according to a preset correlation table of the effective gauge factor versus the temperature.

In this embodiment, the signal processing circuit may be integrated in the semiconductor thin-film, and the signal processing circuit is in connection with the Wheatstone bridge and the temperature sensor, and the temperature value detected by the temperature sensor is applied to a preset sensitivity calibration algorithm to correct the temperature effect of the strain sensing film, the sensitivity calibration algorithm may be derived based on theoretical calculations or data measured under controlled conditions, or based on theoretical calculations and data measured under controlled conditions.

In one of the embodiments, a plurality of temperature sensors are built in the semiconductor thin-film 201, and the signal processing circuit may acquire the temperature of the sensors by performing weighted calculation on a plurality of temperature detection signals output by the plurality of temperature sensors, and then y acquire the corresponding effective gauge factor based on the temperature of the sensors obtained through the weighted calculation.

In one embodiment, the semiconductor thin-film 201 is provided with a plurality of resistors, the plurality of resistors are configured to form a Wheatstone bridge or a half-Wheatstone bridge, and the plurality of resistors are arranged adjacently.

In this embodiment, the plurality of resistors in the Wheatstone bridge or the half Wheatstone bridge are adjacent to each other and insulated from each other. In specific applications, a consistent variation in temperature among the plurality of resistors of the Wheatstone bridge when the temperature varies can be realized due to the good thermal conductivity of semiconductor thin-film 201, and thus errors in pressure detection caused by temperature differences among the resistors on the same semiconductor thin-film 201 can be avoided.

Further, the temperature detection signal is output by the temperature sensor through a temperature contact electrode, and the signal processing circuit may be provided outside the semiconductor thin-film 201. The signal processing circuit can correct the temperature effect of the strain sensing film based on the temperature detection signal output by the temperature sensor built in the semiconductor thin-film 201, for example, the temperature value detected by the temperature sensor is applied by the signal processing circuit to the preset sensitivity calibration algorithm to obtain the effective gauge factor. The sensitivity calibration algorithm may be derived based on theoretical calculations or data measured under controlled conditions, or based on a combination of the theoretical calculations and data measured under controlled conditions.

In one embodiment, the signal processing circuit may also include a voltage source, a current source, an amplifier circuit, an analog-to-digital converter (ADC), a digital-to-analog converter (DAC), a multiplexer (MUX), a micro-controller (MCU) or any other common signal processing and control circuit.

In a specific application, the strain sensing film may operate in a DC mode, and may also operate in an AC mode or a pulsed mode. The strain sensing film may also operate in a low-power sleep mode. The strain sensing films may witch to a high-power detection mode when an external trigger event occurs, and switch back to the low-power mode after the trigger event is passed.

In one embodiment, a bridge contact electrode connected to the Wheatstone bridge or the half Wheatstone bridge is provided on the semiconductor thin-film 201, and configured for outputting a bridge voltage signal.

In one embodiment, the temperature sensor may be connected to the signal processing circuit through a contact electrode, or the temperature sensor may be connected to an external control unit through the contact electrode. The external control unit may be an external signal processing circuit.

In one of the embodiments, the temperature contact electrode may include a conductive contact formed by common printing techniques such as screen printing, inkjet printing, roll-to-roll printing, etc. The conductive contact may also be thermally annealed to form the Ohmic contact electrode, and the conductive contact may also be formed by wire bonding or soldering processes.

In one of the embodiments, the bridge contact electrode may include a conductive contact formed by common printing techniques such as screen printing, inkjet printing, roll-to-roll printing, etc. The conductive contact may also be thermally annealed to form the Ohmic contact electrode, and the conductive contact may also be prepared by the process of wire bonding.

In one of the embodiments, the temperature contact electrode may also be formed by solder ball and flip-chip processes.

In one of the embodiments, the bridge contact electrode may also be formed by solder ball and flip-chip processes.

In a specific application, the effective gauge factor of the semiconductor thin-film varies with the temperature, the higher the temperature, the smaller the effective gauge factor. When the temperature detection signal output by the built-in temperature sensor is used for the calibration of the strain sensing film, the correlation table of the effective gauge factor versus temperature can be obtained through preset calibration tests, then the corresponding effective gauge factor can be obtained through the temperature value corresponding to the temperature detection signal output by the temperature sensor, and then based on the calibrated effective gauge factor, the pressure value detected by the strain sensing film is determined.

In one embodiment, the thickness of the semiconductor thin-film 201 is less than or equal to 70 μm.

In one embodiment, the thickness of the semiconductor thin-film 201 is less than or equal to 50 μm.

In one embodiment, the thickness of the semiconductor thin-film 201 is less than or equal to 30 μm.

In one embodiment, the thickness of the semiconductor thin-film 201 is less than or equal to 25 μm.

In one embodiment, the thickness of the semiconductor thin-film 201 is less than or equal to 20 μm.

In one embodiment, the thickness of the semiconductor thin-film 201 is less than or equal to 15 μm.

In this embodiment, the elastic modulus of the silicon material is equivalent to the elastic modulus of steel, which is about 160 GPa. The larger the thickness, the more difficult the deformation. Thus, the thickness of the silicon wafer may be reduced to be less than or equal to 70 um, or to be less than or equal to 50 um, or to be less than or equal to 30 um, to be less than or equal to 25 um, or to be less than or equal to 20 um, or to be less than or equal to 15 um, at this time, the semiconductor thin-film will become soft and easily deformed, which improves the efficiency of strain transfer from the substrate to the semiconductor thin-film, thereby improving the effective gauge factor of the semiconductor thin-film, and significantly increasing the signal quantity.

In accordance with an embodiment of the present application, it is also provided a strain sensing film, which includes a semiconductor thin-film, and on the semiconductor thin-film, at least two resistors are disposed, one resistor and at least another resistor have different strain levels in a strained state.

In this embodiment, the gauge factor (GF) of the resistance strain gauge represents the relative variation of the strain gauge resistance caused by the unit strain of the resistance strain gauge, where dR/R=GF×∈, dR/R is the resistance-variation rate, ∈ is the mechanical strain of the material. As the strain level of one resistor on the semiconductor thin-film is provided have a strain level different from that of at least another resistor in the strained state, the dR/R of at least two resistors on the semiconductor thin-film are different, At this time, when the semiconductor thin-film is in the strained state, the two resistors respond differently to the strain, and thus two different electrical signals are generated, or at least two resistance values are generated simultaneously, thereby increasing the sensitivity of the semiconductor thin-film, and thus an accurate strain signal can be detected even in small-strain circumstances.

In one of the embodiments, one resistor is arranged in a region having a different strain level with respect to at least another resistor.

In accordance with an embodiment of the present application, it is also provided a pressure sensor. The pressure sensor includes a substrate, and at least one side surface of the substrate is provided with the strain sensing film according to any one of the above embodiments.

In this embodiment, the substrate may include a common substrate used for circuits such as printed circuit boards, flexible printed circuit (FPC) boards, and may include a common substrate used in printable electronics, such as a polyamide Imine (PI) sheet, a polyethylene terephthalate (PET) sheet, a polyurethane (PU) sheet, a polycarbonate (PC) sheet, an epoxy sheet, or may also include a glass fiberboard (FR-4), a glass sheet, a metal sheet, a paper, a composite sheet, a wood sheet, a ceramic sheet, etc.

In a specific application, as shown in FIG. 6, the strain sensing films 5 are arranged on two sides of the substrate 4. Reference sign 3 represents a deformation neutral surface of the substrate, and the substrate 4 is pasted on the panel 1 by the double-sided tape 2. The modulus of the double-sided tape is much smaller than that of the panel 1, and the panel 1 may be made of metal, glass, plastic, ceramic, wood, or the like. By pressing, the panel 1 is deformed, and the sensor module is driven to deform by the double-sided tape. The deformation neutral surface 3 of the pressure sensor module is at the middle position of the sensor as shown in FIG. 6. The deformation values on the upper and lower sides of the module are the same in value and opposite in sign. The strain sensing films are arranged on the upper and lower sides, compared with the strain sensing film arranged on one side, twice the signal can be generated, and thus the signal-to-noise ratio is improved.

In accordance with an embodiment of the present application, it is also provided a hybrid strain sensing system. The hybrid strain sensing system includes: a substrate; a signal processing circuit; and the strain sensing film according to any one of the above embodiments. The strain sensing film is attached to the substrate, and is in connection with the signal processing circuit.

In this embodiment, the strain sensing film is in connection with the signal processing circuit, the strain sensing film is attached to the substrate, or at least one strain sensing film and one signal processing circuit are arranged on the substrate, thereby forming a hybrid strain sensing system to provide high sensitivity and flexibility for various application scenarios.

In one of the embodiments, the mode of attaching may be gluing, mechanical fixing, surface mounting (SMT) and so on.

Fields of application of such strain sensing systems include but are not limited to strain sensing, or force sensing, or touch sensing or tactile sensing of smartphones, in any human-machine interface or machine-machine interaction, such as tablet computers, personal computers, touch screens, virtual reality (VR) systems, gaming systems, consumer electronics, vehicles, scientific instruments, toys, remote controls, industrial machinery, biomedical sensors to monitor heart rate, blood pressure, and movement and acceleration of skin, muscles, bones, joints and other body parts; robotic sensors for measuring touch, local pressure, local tension, motion and acceleration of any part of the robot; vibration sensors for buildings, bridges and any other man-made structures; sensors to monitor strain, pressure, motion, acceleration of any part of a vehicle that may be used on land, air, water or space; motion, acceleration, and strain sensors that can be integrated into smart fabrics; and any other application that requires the measurement of local static or dynamic deformation, displacement or strain.

Embodiments of the present application provide a strain sensing film, a pressure sensor, and a hybrid strain sensing system. The strain sensing film includes a semiconductor thin-film, and the semiconductor thin-film is provided with at least two resistors, one resistor has a different response to a strain with respect to at least another resistor, thereby enhancing resistance to external environmental disturbances and improving the accuracy of pressure measurement.

The forgoing are only optional embodiments of the present application, and are not intended to limit the present application. For those skilled in the art, various modifications and variations of this application are possible. Any modification, equivalent replacement, improvement, and the like, made within the fundamental designs and the principle of the present application, should all be included in the protection scope of the present application.

	Number	Date	Country
	63064086	Aug 2020	US
	62992000	Mar 2020	US

STRAIN SENSING FILM, PRESSURE SENSOR AND HYBRID STRAIN SENSING SYSTEM

Information

Publication Number

Date Filed

Date Published

Inventors

Original Assignees

CPC

International Classifications

Abstract

Description

Claims

CROSS-REFERENCE TO RELATED APPLICATIONS

PCT Information

Provisional Applications (2)