An integrated sensor and its fabrication method

Abstract

This invention discloses an integrated sensor and its fabrication method, belonging to the field of semiconductor technology. The integrated sensor includes at least: a substrate; at least one pressure sensor disposed on the substrate; and at least one temperature sensor disposed on the substrate at a distance from the pressure sensor. The height of the temperature sensor on the substrate is lower than the height of the pressure sensor on the substrate. The integrated sensor and its fabrication method provided by this invention enable the integration of a pressure sensor and a temperature sensor on the same substrate, allowing for the simultaneous measurement of temperature and pressure parameters, expanding the application range of the sensor, and improving the accuracy, reliability, and safety of testing.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor technology, and specifically relates to an integrated sensor and its fabrication method. Background Technology

[0002] Semiconductor sensors possess advantages such as high sensitivity, miniaturization and integration, low power consumption, and low cost, making them widely used in industrial automation, environmental monitoring, and healthcare. With the continuous development of microelectronics and microelectromechanical systems (MEMS) technologies, sensors can achieve smaller sizes and more integrated performance, and their fabrication processes are becoming increasingly mature, representing the main development direction of current sensor technology. Integrated sensors integrate different types of sensing units onto a single sensor chip, enabling the simultaneous measurement of multiple physical quantities.

[0003] However, due to varying adaptability of devices in different environments, such as harsh conditions like high temperatures and high corrosion, silicon-based devices face limitations in such applications. Silicon carbide (SiC), as a third-generation wide-bandgap semiconductor material, with its high thermal conductivity, high stability, and high electron mobility, can meet the requirements of these complex and harsh environments, showing promising application prospects in integrated sensor fabrication. However, technologies for integrating temperature and pressure sensors based on silicon carbide have not yet emerged. Summary of the Invention

[0004] The purpose of this invention is to provide an integrated sensor and its manufacturing method. The integrated sensor and its manufacturing method provided by this invention can integrate a pressure sensor and a temperature sensor on the same substrate, enabling simultaneous measurement of temperature and pressure parameters, expanding the application range of the sensor, and improving the accuracy, reliability, and safety of testing.

[0005] To address the aforementioned technical problems, the present invention provides an integrated sensor, comprising at least the following steps:

[0006] Substrate;

[0007] At least one pressure sensor is disposed on the substrate; and

[0008] At least one temperature sensor is disposed on the substrate at a distance from the pressure sensor; the height of the temperature sensor on the substrate is lower than the height of the pressure sensor on the substrate.

[0009] In one embodiment of the present invention, the pressure sensor includes a first sensing portion and a first metal electrode, wherein the first metal electrode extends from both sides of the top of the first sensing portion to the substrate.

[0010] In one embodiment of the present invention, the temperature sensor includes a second sensing portion and a second metal electrode. The second metal electrode extends from both sides of the top of the second sensing portion to the substrate. The thickness of the second sensing portion is less than the thickness of the first sensing portion.

[0011] In one embodiment of the present invention, the substrate is an intrinsic silicon carbide layer, and the first sensing portion and the second sensing portion are N-type silicon carbide layers, wherein the doping concentration of the N-type silicon carbide layer is 1×10⁻⁶. 18 atoms / cm 3 ~1×10 19 atoms / cm 3 .

[0012] In one embodiment of the present invention, the pressure sensor and the temperature sensor are arranged linearly, in a grid, staggered, or layered manner.

[0013] The present invention also provides a method for manufacturing an integrated sensor, comprising at least the following steps:

[0014] Provide a substrate;

[0015] At least one pressure sensor is formed on the substrate; and

[0016] At least one temperature sensor is formed on the substrate, and the temperature sensor and the pressure sensor are disposed on the substrate at a distance; the height of the temperature sensor on the substrate is lower than the height of the pressure sensor on the substrate.

[0017] In one embodiment of the present invention, the manufacturing method further includes:

[0018] Provide a substrate;

[0019] A sensing layer is formed on the substrate;

[0020] A first patterned photoresist layer is formed on the sensing layer;

[0021] Using the first patterned photoresist layer as a mask, a portion of the sensing layer is etched to the substrate to form a spaced first sensing portion and a second sensing portion.

[0022] Remove the first patterned photoresist layer, and form a second patterned photoresist layer on the first sensing portion, the second sensing portion, and the substrate, wherein the second patterned photoresist layer exposes the second sensing portion; and

[0023] Thin the second sensing portion.

[0024] In one embodiment of the present invention, the thickness of the second sensing portion is one-third to two-thirds of the thickness of the first sensing portion.

[0025] In one embodiment of the present invention, the manufacturing method further includes:

[0026] A metal layer is formed on the substrate, on the top and sidewalls of the first sensing portion and the second sensing portion;

[0027] A third patterned photoresist layer is formed on the metal layer, the third patterned photoresist layer exposing the substrate, the first sensing portion, and a portion of the metal layer above the second sensing portion; and

[0028] Using the third patterned photoresist layer as a mask, the metal layer is etched to form the first metal electrode and the second metal electrode.

[0029] In one embodiment of the present invention, the material of the metal layer is at least one of nickel, titanium, gold or platinum, and the thickness of the metal layer is 40 nm to 70 nm.

[0030] In one embodiment of the present invention,

[0031] In summary, this invention provides an integrated sensor and its fabrication method. By improving the integrated sensor and its fabrication method, a pressure sensor and a temperature sensor can be integrated on the same substrate to form a single chip, enabling simultaneous measurement of temperature and pressure parameters and expanding the sensor's application range. It simplifies the fabrication process, reduces fabrication steps, compresses sensor processing costs, and improves manufacturing efficiency. It avoids interference between the pressure and temperature sensors, improving test accuracy. It avoids the reliability issues of heterogeneous materials and electrical connections inherent in metal thermocouples, resistance temperature detectors (RTDs), and Schottky temperature sensors, improving the reliability and safety of the integrated sensor.

[0032] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0033] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 This is a schematic diagram of an integrated sensor in one embodiment.

[0035] Figure 2 For along Figure 1 A schematic diagram of the sensing layer formed in the AA direction.

[0036] Figure 3For along Figure 1 A schematic diagram of the formation of the first patterned photoresist layer in the AA direction.

[0037] Figure 4 For along Figure 1 A schematic diagram showing the formation of the first and second induction portions along the AA direction.

[0038] Figure 5 For along Figure 1 A schematic diagram of the second patterned photoresist layer formed in the AA direction.

[0039] Figure 6 For along Figure 1 A schematic diagram of the second sensing section being thinned in the AA direction.

[0040] Figure 7 For along Figure 1 A schematic diagram of a metal layer formed in the AA direction.

[0041] Figure 8 For along Figure 1 A schematic diagram of the formation of the third patterned photoresist layer in the AA direction.

[0042] Figure 9 For along Figure 1 A schematic diagram showing the formation of the first and second metal electrodes along the AA direction.

[0043] Label Explanation:

[0044] 10. Substrate; 11. Sensing layer; 111. First sensing portion; 112. Second sensing portion; 12. First patterned photoresist layer; 121. First opening; 13. Second patterned photoresist layer; 131. Second opening; 14. Metal layer; 141. First metal electrode; 142. Second metal electrode; 15. Third patterned photoresist layer; 151. Third opening; 16. Pressure sensor; 17. Temperature sensor. Detailed Implementation

[0045] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0046] It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0047] In this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first" and "second" are used only for descriptive and distinguishing purposes and should not be construed as indicating or implying relative importance.

[0048] Among the many SiC-based sensor designs, pressure and temperature sensors each have corresponding technical solutions. SiC pressure sensors primarily utilize piezoresistive and capacitive technologies: piezoresistive sensors leverage the piezoresistive effect of SiC, where resistivity changes under pressure; capacitive sensors obtain pressure information by measuring changes in capacitance, which alter the distance or dielectric constant between SiC capacitor plates. SiC temperature sensors mainly employ resistance temperature detectors (RTDs) and diodes: RTDs utilize the change in SiC resistance with temperature to obtain temperature information; diodes utilize the voltage-temperature relationship of a SiC diode to determine temperature. However, integrating temperature and pressure sensors into SiC materials presents significant design challenges. This invention proposes an integrated sensor and its fabrication method. The fabrication process is simple, enabling the integration of a piezoresistive pressure sensor and an RTD-based temperature sensor onto the same SiC substrate, forming a single chip that simultaneously measures both temperature and pressure parameters.

[0049] Please see Figure 1As shown, in one embodiment of the present invention, the integrated sensor includes a substrate 10, at least one pressure sensor 16 and at least one temperature sensor 17 disposed on the substrate 10, etc. The height of the temperature sensor 17 on the substrate 10 is lower than the height of the pressure sensor 16 on the substrate 10, and this application does not limit the relative positions of the pressure sensor 16 and the four temperature sensors 17. In this embodiment, the integrated sensor includes, for example, one pressure sensor 16 and four temperature sensors 17, with the temperature sensors 17 symmetrically disposed on both sides of the pressure sensor 16. In other embodiments, the number and arrangement of the pressure sensor 16 and the temperature sensor 17 are set according to the usage environment, such as linear, grid, staggered, or layered arrangements.

[0050] Please see Figure 1 As shown, in one embodiment of the present invention, the pressure sensor 16 includes a first sensing portion 111 and a first metal electrode 141. The first metal electrode 141 extends from both sides of the top of the first sensing portion 111 onto the substrate 10. The temperature sensor 17 includes a second sensing portion 112 and a second metal electrode 142. The second metal electrode 142 extends from both sides of the top of the second sensing portion 112 onto the substrate 10. In this application, the pressure sensor 16 and temperature sensor 17 have simple structures and can simultaneously measure temperature and pressure parameters, expanding the application range of SiC-based sensors. In this application, [the following is a more detailed description of the design and specifications of the sensors]. Figure 1 Taking the AA-direction cross-sectional view as an example, the manufacturing method of the integrated sensor is explained.

[0051] Please see Figure 2 As shown, in one embodiment of the present invention, the substrate 10 is, for example, a silicon carbide substrate, or an intrinsic silicon carbide substrate, and the thickness of the substrate 10 is not specifically limited, but is selected according to the fabrication requirements. A sensing layer 11 is formed on the substrate 10, and the sensing layer 11 is, for example, an N-type silicon carbide layer. The N-type silicon carbide layer is formed, for example, by chemical vapor deposition (CVD) or epitaxial growth, and then obtained by ion implantation. In other embodiments, the dopant ions in the sensing layer 11 are formed, for example, by co-precipitation.

[0052] Please see Figure 2As shown, in one embodiment of the present invention, a silicon carbide substrate is placed in a transfer chamber filled with inert gas and transferred to a silicon carbide CVD reaction chamber with a hydrogen atmosphere using a robotic arm. The reaction chamber has an initial pressure and an initial temperature. Hydrogen gas is continuously supplied to the reaction chamber, and the temperature and pressure of the reaction chamber are set to a first temperature and a first pressure. After the temperature and pressure of the reaction chamber gradually reach the set values ​​and stabilize, they are maintained for a period of time. A carbon source and a silicon source are used as the growth source gas. If the silicon source is liquid, the liquid silicon source is stored in a bubbler, and hydrogen gas is introduced into the bubbler, carrying the silicon source into the reaction chamber. The carbon source includes, but is not limited to, at least one of propane, ethylene, chloromethane, or methane; the silicon source includes, but is not limited to, at least one of silane, trichlorosilane, dichlorosilane, silicon tetrachloride, or methyltrichlorosilane; the initial pressure of the reaction chamber is, for example, 800 mbar to 1200 mbar; the initial temperature is, for example, 500°C to 700°C; the first temperature is, for example, 1600°C to 1700°C; the first pressure is, for example, 50 mbar to 300 mbar; the hydrogen flow rate is, for example, 50 sccm to 200 sccm; the carbon source gas flow rate is, for example, 50 sccm to 200 sccm; and the amount of carbon and silicon sources introduced is maintained at a C / Si molar ratio of, for example, 0.9 to 1.3. The thickness of the formed sensing layer 11 is controlled by controlling the deposition time. This application does not limit the thickness of the sensing layer 11; in this embodiment, the thickness of the sensing layer 11 is, for example, 800 nm to 1200 nm. After deposition, the silicon carbide layer is doped, for example by ion implantation, with the doping ions being N-type ions such as nitrogen or phosphorus, and the doping concentration being, for example, 1 × 10⁻⁶. 18 atoms / cm 3 ~1×10 19 atoms / cm 3 (abbreviated as cm) -3 By controlling the doping concentration, the sensitivity of the sensor can be controlled. By selecting a silicon carbide substrate, the sensing layer 11 and the substrate 10 are made of the same material. When forming the sensing layer 11, the preparation of buffer layers and other components can be reduced, thus reducing the number of process steps, compressing the processing cost of the sensor, and improving manufacturing efficiency.

[0053] Please see Figures 2 to 3 As shown, in one embodiment of the present invention, after forming the sensing layer 11, a photoresist layer is formed on the sensing layer 11. After exposure, development and other processes, a first patterned photoresist layer 12 is formed. The first patterned photoresist layer 12 includes a plurality of first openings 121. The first openings 121 expose a portion of the sensing layer 11. The first patterned photoresist layer 12 is used to define the position of the sensor.

[0054] Please see Figures 3 to 4As shown, in one embodiment of the present invention, using a first patterned photoresist layer 12 as a mask and a substrate 10 as an etching stop layer, etching is performed towards the substrate 10 using, for example, wet etching, dry etching, or a combination of dry and wet etching, to remove a portion of the sensing layer 11, thereby forming multiple first sensing portions 111 and multiple second sensing portions 112 to determine the number and location of pressure sensors and temperature sensors. In this embodiment, for example, dry etching is used to remove a portion of the sensing layer 11, and the etching gas includes, for example, one or a mixture of several of chlorine (Cl2), sulfur hexafluoride (SF6), nitrogen trifluoride (NF3), or carbon tetrafluoride (CF4), or a mixture of them and oxygen (O2). In this embodiment, after forming the first sensing portions 111 and multiple second sensing portions 112, the first patterned photoresist layer 12 is removed by wet cleaning or ashing treatment.

[0055] Please see Figures 4 to 5 As shown, in one embodiment of the present invention, after removing the first patterned photoresist layer 12, a photoresist layer is formed on the first sensing portion 111, the second sensing portion 112 and the substrate 10. After exposure, development and other processes, a second patterned photoresist layer 13 is formed. The second patterned photoresist layer 13 includes a plurality of second openings 131, which expose the second sensing portion 112. The second patterned photoresist layer 13 is used as a photoresist to thin the second sensing portion 112.

[0056] Please see Figures 5 to 6 As shown, in one embodiment of the present invention, the second patterned photoresist layer 13 is used as a mask, and the second sensing portion 112 is thinned using, for example, wet etching, dry etching, or a combination of dry and wet etching, so that the height of the temperature sensor is lower than the height of the pressure sensor, thereby avoiding mutual interference between the pressure sensor and the temperature sensor and improving the accuracy of the test. In this embodiment, for example, dry etching is used to thin the second sensing portion 112, and the etching gas includes, for example, one or more of chlorine, sulfur hexafluoride, nitrogen trifluoride, or carbon tetrafluoride, or a mixture of them and oxygen. In this embodiment, after thinning the second sensing portion 112, the second patterned photoresist layer 13 is removed by wet cleaning or ashing treatment. This application does not limit the thickness relationship between the first sensing portion 111 and the second sensing portion 112, as long as the thickness of the second sensing portion 112 is less than the thickness of the first sensing portion 111. In a specific embodiment of the present invention, the thickness of the second sensing portion 112 is, for example, one-third to two-thirds of the thickness of the first sensing portion 111.

[0057] Please see Figures 6 to 7As shown, in one embodiment of the present invention, after thinning the second sensing portion 112, a metal layer 14 is formed on the substrate 10, on the top and sidewalls of the first sensing portion 111 and the second sensing portion 112. The material of the metal layer 14 is, for example, nickel (Ni), titanium (Ti), gold (Au), or platinum (Pt), and the thickness of the metal layer 14 is, for example, 40 nm to 70 nm. The metal layer 14 is deposited, for example, by physical vapor deposition or electroplating.

[0058] Please see Figures 7 to 8 As shown, in one embodiment of the present invention, after forming the metal layer 14, a photoresist layer is formed on the metal layer 14. After exposure, development and other processes, a third patterned photoresist layer 15 is formed. The third patterned photoresist layer 15 includes a plurality of third openings 151. The third openings 151 expose a portion of the metal layer 14 on the substrate 10, the first sensing portion 111 and the second sensing portion 112, so as to remove a portion of the metal layer 14 and form a metal electrode.

[0059] Please see Figures 8 to 9 As shown, in one embodiment of the present invention, after forming the third patterned photoresist layer 15, the third patterned photoresist layer 15 is used as a mask, and the substrate 10, the first sensing portion 111, and the second sensing portion 112 are used as etching stop layers. For example, wet etching, dry etching, or a combination of dry and wet etching are used to etch the metal layer 14 to form the first metal electrode 141 and the second metal electrode 142. In this embodiment, for example, a portion of the metal layer 14 is removed by dry etching, and the etching gas is, for example, one or a mixture of several of oxygen, argon (Ar), nitrogen (N2), hydrogen bromide (HBr), or boron trichloride (BCl3). After etching, the first metal electrode 141 extends from both sides of the top of the first sensing portion 111 onto the substrate 10, covering a portion of the first sensing portion 111, its sidewalls, and a portion of the substrate 10. The first metal electrodes 141 on the first sensing portion 111 are spaced apart, and the first metal electrode 141 and the first sensing portion 111 constitute the pressure sensor 16. The second metal electrode 142 extends from both sides of the top of the second sensing portion 112 onto the substrate 10, covering a portion of the second sensing portion 112, its sidewalls, and a portion of the substrate 10. The second metal electrodes 142 on the second sensing portion 112 are spaced apart, and the second metal electrode 142 and the second sensing portion 112 constitute the temperature sensor 17. Through the fabrication method of this application, the pressure sensor 16 and the temperature sensor 17 can be integrated onto the same substrate. The integrated sensor has a simple structure, simplifies the fabrication process, and can simultaneously measure temperature and pressure parameters, thus expanding the application range of the integrated sensor.

[0060] Please see Figure 1 and Figure 9As shown, in one embodiment of the present invention, in the pressure sensor 16, the first metal electrodes 141 on both sides of the first sensing portion 111 serve as the positive and negative electrodes of the pressure sensor 16, respectively. In the temperature sensor 17, the second metal electrodes 142 on both sides of the second sensing portion 112 serve as the positive and negative electrodes of the temperature sensor 17, respectively. The SiC-based integrated sensor obtained in this application can avoid the reliability problems of heterogeneous materials and electrical connection problems existing in metal thermocouples, resistance temperature detectors (RTDs), and Schottky temperature sensors, thereby improving the reliability and safety of the integrated sensor.

[0061] In one embodiment of the present invention, the basic principle of the SiC-based temperature sensor is the impurity ionization theory. In a doped silicon carbide layer, the impurity ionization energy of the dopant ions in silicon carbide is relatively large, and incomplete ionization of impurities occurs at room temperature. The incomplete ionization model is expressed by the following formula:

[0062]

[0063] Where k is the Boltzmann constant (eV / K), and T is the absolute temperature (K). It is the concentration of ionized donor impurities (cm). -3 ), It is the concentration of ionized acceptor impurities (cm). -3 ), N D It is the actual donor impurity concentration (cm²) -3 ), N A It is the actual acceptor impurity concentration (cm). -3 ), g D and g A G represents the degeneracy factors of the donor and acceptor impurity levels, respectively (usually set to 2 and 4). D (T) and G A (T) represent the donor impurity ionization factor and the acceptor impurity ionization factor, respectively, and E Fn and E Fp These are the electron and hole Fermi levels, E, respectively. C and E V These are the bottom conduction band level and the top valence band level, respectively. D and E A The impurity energy levels for the donor and acceptor atoms are ΔE, respectively. D and ΔE A These are the ionization energies of donor impurities and acceptor impurities, respectively.

[0064] Meanwhile, the intrinsic carrier concentration n i for:

[0065]

[0066] Where A is a material-related constant, E gis the bandgap width, k is the Boltzmann constant, and T is the absolute temperature.

[0067] For N-type SiC materials, the carrier concentration n can be obtained from the electroneutrality condition:

[0068]

[0069] Meanwhile, the expression for the mobility μ is:

[0070] μ=μ0T -m

[0071] Where μ0 is the mobility related to bulk phonon scattering, T is the absolute temperature, and m is a constant related to the material and scattering mechanism.

[0072] After obtaining the carrier concentration and mobility, the conductivity can be calculated using the following formula:

[0073] σ=nqμ

[0074] Where σ is the conductivity, n is the carrier concentration, q is the carrier charge, and μ is the carrier mobility.

[0075] Please see Figure 1 and Figure 9 As shown, in one embodiment of the present invention, for a SiC-based temperature sensor, the basic measurement method is achieved by measuring resistance. This is obtained from the formula:

[0076]

[0077] Where R is the resistance, l is the length of the sensing region between the metal electrodes, σ is the conductivity of the sensing region material, and S is the cross-sectional area of ​​the sensing region between the metal electrodes.

[0078] The basic principle of SiC pressure sensors is based on scattering theory. When pressure is applied to a SiC thin film, its internal crystal structure is distorted, causing changes in acoustic phonon scattering and ionized impurity scattering, which in turn leads to changes in carrier mobility. This, in turn, causes a change in resistivity, and the relationship between the resistance value and stress is as follows: Where ρ is the resistivity of the material in the initial state, Δρ is the change in resistivity of the material after stress is applied, R is the resistance value of the material in the initial state, ΔR is the change in resistance value of the material after stress is applied, π is the piezoresistive coefficient of the material, and F is the stress on the material.

[0079] Please see Figure 1 and Figure 9As shown, in one embodiment of the present invention, during the use of the integrated sensor, when the pressure changes, the lattice structure of the first sensing portion 111 changes, thereby affecting its resistivity and resistance value. Pressure can be measured by measuring the change in resistance value through the first metal electrode 141. When the temperature changes, the carrier concentration in the second sensing portion 112 changes, and the resistance value measured by the two second metal electrodes 142 also changes accordingly. Temperature can be measured by measuring the change in resistance value. However, since the first sensing portion 111 is also affected by temperature changes, in the design process, the first sensing portion 111 is higher than the second sensing portion 112. During the packaging process, for example, the temperature sensor 17 and the pressure sensor 16 are packaged separately to avoid pressure affecting the temperature sensor 17. During testing, the resistance values ​​are measured through the first metal electrode 141 and the second metal electrode 142 respectively, and the temperature and pressure changes are obtained based on the test results. Specifically, if the changes in resistance values ​​measured by the first metal electrode 141 and the second metal electrode 142 are similar, the temperature change is obtained based on the resistance values ​​measured by the first metal electrode 141 and the second metal electrode 142, while the pressure change is essentially unchanged. If the changes in resistance values ​​measured by the first metal electrode 141 and the second metal electrode 142 differ significantly, the temperature change is obtained based on the change in the resistance value of the second metal electrode 142, and the pressure change is obtained based on the difference in resistance values ​​measured by the first metal electrode 141 and the second metal electrode 142. If the resistance value measured by the first metal electrode 141 changes, while the resistance value measured by the second metal electrode 142 remains essentially unchanged, the pressure change is obtained based on the resistance value measured by the first metal electrode 141, while the temperature change is essentially unchanged. In other words, during the measurement process, the changes in temperature and pressure can be obtained separately based on the resistance values ​​measured by the pressure sensor and the temperature sensor.

[0080] Please see Figure 1 and Figure 9 As shown, in one embodiment of the present invention, polydimethylsiloxane (PDMS) is used to encapsulate the integrated sensor, and the resulting integrated sensor is used, for example, in a lithium-ion battery. This makes the performance of the integrated sensor, which operates in the electrolyte, more stable, and can monitor changes in temperature and pressure in a timely manner, thereby improving the safety performance of the lithium-ion battery.

[0081] In summary, this invention provides an integrated sensor and its fabrication method. By improving the integrated sensor and its fabrication method, a pressure sensor and a temperature sensor can be integrated on the same substrate to form a single chip, enabling simultaneous measurement of temperature and pressure parameters and expanding the sensor's application range. It simplifies the fabrication process, reduces fabrication steps, compresses sensor processing costs, and improves manufacturing efficiency. It avoids interference between the pressure and temperature sensors, improving test accuracy. It avoids the reliability issues of heterogeneous materials and electrical connections inherent in metal thermocouples, resistance temperature detectors (RTDs), and Schottky temperature sensors, improving the reliability and safety of the integrated sensor.

[0082] Throughout this specification, the terms "one embodiment," "an embodiment," or "a specific embodiment" refer to a particular feature, structure, or characteristic described in connection with an embodiment that is included in at least one embodiment of the invention, but not necessarily in all embodiments. Therefore, the various representations of the phrases "in one embodiment," "in an embodiment," or "in a specific embodiment" in different places throughout the specification do not necessarily refer to the same embodiment. Furthermore, a particular feature, structure, or characteristic of any specific embodiment of the invention may be combined with one or more other embodiments in any suitable manner. It should be understood that other variations and modifications of the embodiments of the invention described and illustrated herein may be based on the teachings herein and will be considered part of the spirit and scope of the invention.

[0083] It should also be understood that the above-disclosed embodiments of the present invention are merely illustrative of the invention. The embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. These embodiments have been selected and specifically described in this specification to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method of fabricating an integrated sensor, comprising: At least comprising the following steps: providing a substrate; forming at least one pressure sensor on the substrate; and forming at least one temperature sensor on the substrate, the temperature sensor being spaced apart from the pressure sensor on the substrate; the height of the temperature sensor on the substrate being lower than the height of the pressure sensor on the substrate; the manufacturing method of the pressure sensor and the temperature sensor comprising: forming a sensing layer on the substrate; forming a first patterned photoresist layer on the sensing layer; using the first patterned photoresist layer as a mask, etching part of the sensing layer to the substrate to form spaced first and second sensing subparts; removing the first patterned photoresist layer, forming a second patterned photoresist layer on the first and second sensing subparts and the substrate, the second patterned photoresist layer exposing the second sensing subpart; thinning the second sensing subpart; removing the second patterned photoresist layer; forming a metal electrode on the first and second sensing subparts, the metal electrode extending from both sides of the top of the first or second sensing subpart to the substrate, respectively.

2. The method of claim 1, wherein, The thickness of the second sensing subpart is one third to two thirds of the thickness of the first sensing subpart.

3. The method of claim 1, wherein the step of forming the integrated sensor is performed by a process selected from the group consisting of: photolithography, e-beam lithography, and nano-imprint lithography. The manufacturing method further comprises: forming a metal layer on the substrate, the top and sidewall of the first and second sensing subparts; forming a third patterned photoresist layer on the metal layer, the third patterned photoresist layer exposing part of the metal layer on the substrate, the first and second sensing subparts; and using the third patterned photoresist layer as a mask, etching the metal layer to form a first and second metal electrode.

4. The method of claim 3, wherein the step of forming the integrated sensor is performed by a process selected from the group consisting of: photolithography, e-beam lithography, and nano-imprint lithography. The material of the metal layer is at least one of nickel, titanium, gold or platinum, and the thickness of the metal layer is 40-70 nm.

5. An integrated sensor obtained by the method according to any one of claims 1 to 4, characterized in that At least comprising: a substrate; at least one pressure sensor disposed on the substrate; and at least one temperature sensor spaced apart from the pressure sensor on the substrate; the height of the temperature sensor on the substrate being lower than the height of the pressure sensor on the substrate; The pressure sensor comprises a first sensing subpart and a first metal electrode, the first metal electrode extending from both sides of the top of the first sensing subpart to the substrate, respectively. The temperature sensor comprises a second sensing subpart and a second metal electrode, the second metal electrode extending from both sides of the top of the second sensing subpart to the substrate, respectively, and the thickness of the second sensing subpart is less than the thickness of the first sensing subpart.

6. An integrated sensor according to claim 5, wherein, The substrate is an intrinsic silicon carbide layer, the first sensing section and the second sensing section are N-type silicon carbide layers, the doping concentration of the N-type silicon carbide layers is 1x10 18 atoms / cm 3 ~1x10 19 atoms / cm 3 .

7. The integrated sensor of claim 5, wherein, The pressure sensor and the temperature sensor are arranged linearly, in a grid, staggered or in layers.

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