Dual-chamber cascaded acceleration-temperature sensor and its preparation method

Abstract

The present application relates to a dual-chamber cascaded acceleration-temperature sensor, which includes an acceleration sensor structure and a temperature sensor structure arranged vertically. The acceleration sensor structure is an inertial motion structure composed of a cantilever beam-mass block combination. When the sensor is subjected to an acceleration parallel to the direction of the air cavity, the mass block generates a displacement due to the influence of inertia, which in turn causes a change in the length of the air cavity, thereby causing a wavelength shift of the interference spectrum. The temperature sensor structure is composed of a single-crystalline silicon cavity and optical films on the upper and lower sides. When the temperature changes, the volume of the silicon changes accordingly, resulting in a change in the length of the silicon cavity, thereby causing a wavelength shift of the interference spectrum. The difference between the air cavity and the silicon cavity is more than one order of magnitude. The light beam is vertically incident from above the sensor mass block, passes through the air cavity and the silicon cavity and then exits. The exiting light carries the wavelength shift information caused by the changes in the lengths of the air cavity and the silicon cavity. By demodulating the exiting light, the acceleration and temperature can be measured simultaneously.

Description

Technical Field

[0001] This application belongs to the field of optical sensing technology, and particularly relates to a dual-cavity cascaded F-P acceleration-temperature sensor and a preparation method thereof. Background Art

[0002] A Fabry-Perot interferometer (F-P) consists of a rectangular f-p cavity formed by combining a cover plate and a substrate. An incident light emitted by a light source enters the sensor through fiber optic coupling, reflects back and forth between the upper and lower surfaces of the F-P cavity in the sensor, forming multi-beam interference. Part of the reflected light beam returns along the original path and meets to generate interference. The interference signal is related to the cavity length L. When the measured quantity changes, causing displacement or deformation on one side of the cavity and resulting in a change in the cavity length L, the interference signal changes. By measuring the change in the interference signal, the change in the cavity length L can be derived, thereby obtaining the change in the measured quantity.

[0003] Chinese Patent Document CN113029381A discloses a high-precision temperature sensor based on a quartz tube encapsulated PDMS cavity and an air cavity. Both the air cavity and the PDMS cavity are Fabry-Perot interferometers. The Fabry-Perot interferometer is a sensing interferometer sensitive to the measured parameter, and the two interferometers have opposite temperature responses to temperature, thereby improving the sensitivity of temperature measurement. It can be seen that existing dual-cavity cascaded optical sensors all measure a single physical quantity. Since the Fabry-Perot interferometer is also affected by temperature, when measuring physical quantities such as acceleration, it is necessary to measure the temperature simultaneously for compensation. Therefore, a sensor capable of measuring acceleration and temperature simultaneously is needed. Summary of the Invention

[0004] The technical problem to be solved by the present invention is: to provide a dual-cavity cascaded F-P acceleration-temperature sensor and a preparation method thereof for simultaneous measurement of acceleration and temperature to solve the deficiencies in the prior art. [[ID=A]] [[ID=B]]

[0005] The technical solution adopted by the present invention to solve its technical problem is:

[0006] A dual-cavity cascaded acceleration-temperature sensor includes an acceleration sensor structure and a temperature sensor structure arranged up and down;

[0007] The acceleration sensor structure includes:

[0008] Side walls, with a cavity formed in the middle;

[0009] A mass block, located in the middle of the side walls, and the top and bottom surfaces of the mass block are respectively coated with a first optical film;

[0010] A cantilever beam, connecting the mass block and the side walls, providing support for the mass block;

[0011] The temperature sensor structure includes:

[0012] A silicon-based material is disposed below the sidewall, and second optical films are respectively plated on the top and bottom of the silicon-based material;

[0013] The transmittance and refractive index of the first optical film and the second optical film are equal, and the distance between the first optical film below the mass block and the second optical film at the top of the silicon-based material is h1, the refractive index of the mass block is n1, the distance between the second optical films at the top and bottom of the silicon-based material is h2, the refractive index of the silicon-based material is n2, and lg[h1*n1 / (h2*n2)] is less than 1, where lg is the common logarithm.

[0014] Preferably, for the dual-cavity cascaded acceleration-temperature sensor of the present invention, the silicon-based material has a concave structure, the upper hollow part forms an air cavity with the cavity, and the top of the silicon-based material is at the top of the hollow part.

[0015] Preferably, for the dual-cavity cascaded acceleration-temperature sensor of the present invention, the cantilever beam is a cantilever beam.

[0016] Preferably, for the dual-cavity cascaded acceleration-temperature sensor of the present invention, the acceleration sensor structure and the temperature sensor structure are bonded by BCB glue.

[0017] Preferably, for the dual-cavity cascaded acceleration-temperature sensor of the present invention, the acceleration sensor structure is prepared from a SOI wafer.

[0018] Preferably, for the dual-cavity cascaded acceleration-temperature sensor of the present invention, the SOI wafer has a 5-layer structure, which are a first silicon layer, a first silicon oxide layer, a second silicon layer, a second silicon oxide layer, and a third silicon layer respectively.

[0019] The present invention also provides a preparation method for a dual-cavity cascaded acceleration-temperature sensor, for preparing the above-mentioned dual-cavity cascaded acceleration-temperature sensor, including:

[0020] Steps for preparing the acceleration sensor structure:

[0021] S11: Take a SOI wafer, and the SOI wafer has a layer structure, which are a first silicon layer, a first silicon oxide layer, a second silicon layer, a second silicon oxide layer, and a third silicon layer respectively;

[0022] S12: Coat photoresist on the top of the first silicon layer, leave the corresponding area of the mass block to be processed blank, then deposit a metal layer and clean the photoresist to form the first optical film on the top of the mass block;

[0023] S13: Coat photoresist on the bottom of the third silicon layer, leave the area between the mass block and the sidewall blank, and etch the area between the mass block and the sidewall;

[0024] S14: Remove the photoresist at the bottom of the third silicon layer corresponding to the mass block, and etch from the bottom of the third silicon layer to form a mass block with the required thickness.

[0025] S15: Coat the surface of the SOI wafer in the mass-block removal area processed in step S from the bottom with photoresist, deposit a metal layer on the bottom surface of the mass block, and then clean the photoresist to form the first optical film at the bottom of the mass block.

[0026] S16: Coat the surface of the areas corresponding to the cantilever beam and the side wall in the SOI wafer processed in step S from the top with photoresist, etch the SOI wafer from the top to form a cantilever beam, and clean off the photoresist to complete the preparation of the acceleration sensor structure.

[0027] Steps for preparing the temperature sensor structure:

[0028] S21: Take a silicon wafer, coat the surface of the silicon wafer with photoresist except for the hollow part on the top surface, etch the silicon wafer so that the whole silicon wafer forms a concave-shaped structure, and clean the photoresist.

[0029] S22: Coat the surface of the silicon wafer on the top except for the area corresponding to the second optical film on the top of the silicon-based material with photoresist, then deposit a metal layer on the top surface of the silicon wafer and clean the photoresist to form the second optical film on the top of the silicon-based material.

[0030] S23: Coat the surface of the silicon wafer on the bottom except for the area corresponding to the second optical film on the bottom of the silicon-based material with photoresist, then deposit a metal layer on the bottom surface of the silicon wafer and clean the photoresist to form the second optical film on the bottom of the silicon-based material, thus completing the preparation of the temperature sensor structure.

[0031] Combination step:

[0032] Bond the bottom of the acceleration sensor structure to the top of the temperature sensor structure.

[0033] Preferably, in the preparation method of the dual-cavity cascaded acceleration-temperature sensor of the present invention, before the combination step, bond bumps on the top of the acceleration sensor structure.

[0034] Preferably, in the preparation method of the dual-cavity cascaded acceleration-temperature sensor of the present invention, the acceleration sensor structure and the temperature sensor structure are bonded by BCB glue.

[0035] Preferably, in the preparation method of the dual-cavity cascaded acceleration-temperature sensor of the present invention, the bonding process is carried out in a vacuum environment.

[0036] The beneficial effects of the present invention are:

[0037] The dual - cavity cascaded acceleration - temperature sensor of the present invention includes an acceleration sensor structure and a temperature sensor structure arranged vertically. The acceleration sensor structure is an inertial motion structure composed of a cantilever beam - mass block combination. When the sensor is subjected to an acceleration parallel to the direction of the air cavity, the mass block generates a displacement due to inertia, which in turn causes a change in the length of the air cavity, thereby causing a wavelength shift in the interference spectrum. The temperature sensor structure is composed of a silicon cavity made of single - crystal silicon and optical films on both the upper and lower sides. When the external temperature changes, the volume of silicon changes accordingly, resulting in a change in the length of the silicon cavity and thus causing a wavelength shift in the interference spectrum. The difference between the air cavity and the silicon cavity is more than one order of magnitude. The light beam is incident vertically from above the sensor mass block, passes through the air cavity and the silicon cavity, and the outgoing light carries the wavelength shift information caused by the changes in the lengths of the air cavity and the silicon cavity. By demodulating the outgoing light, the acceleration and temperature can be measured simultaneously. Description of the Drawings

[0038] The technical solutions of the present application will be further described below in conjunction with the drawings and embodiments.

[0039] Figure 1 is a cross - sectional view of the dual - cavity cascaded acceleration - temperature sensor of Embodiment 1 of the present application;

[0040] Figure 2 is Figure 1 a schematic diagram for identifying the cavity length in

[0041] Figure 3 is a schematic diagram of the structure of the cantilever beam in the dual - cavity cascaded acceleration - temperature sensor of Embodiment 1 of the present application;

[0042] Figure 4 is a flowchart of the preparation steps of the acceleration sensor structure of Embodiment 2 of the present application;

[0043] Figure 5 is a flowchart of the preparation steps of the acceleration sensor structure of Embodiment 2 of the present application;

[0044] Figure 6 is a simulation diagram of the transmission spectrum of the sensor when the product of the refractive index and the cavity length of the air cavity and the silicon cavity is close in the effect embodiment;

[0045] Figure 7 is a simulation diagram of the transmission spectrum of the sensor when the product of the refractive index and the cavity length of the air cavity and the silicon cavity differs by one order of magnitude in the effect embodiment;

[0046] Figure 8 is a simulation diagram of the cascaded spectrum of the sensor under the influence of acceleration in the effect embodiment;

[0047] Figure 9 is a simulation diagram of the cascaded spectrum of the sensor under the influence of temperature in the effect embodiment;

[0048] The reference numerals in the figures are as follows:

[0049] 11 Side wall;

[0050] 12 Cantilever beam;

[0051] 13 Mass block;

[0052] 14 Cavity;

[0053] 15 First optical film;

[0054] 22 Silicon-based material;

[0055] 23 Second optical film;

[0056] 24 Second optical film;

[0057] 71 First silicon layer;

[0058] 72 First silicon oxide layer;

[0059] 73 Second silicon layer;

[0060] 74 Second silicon oxide layer;

[0061] 75 Third silicon layer;

[0062] 76 Bump;

[0063] 8 Silicon wafer;

[0064] 9 Photoresist. Detailed implementation manners

[0065] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments may be combined with each other.

[0066] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the protection scope of the present application. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more.

[0067] In the description of the present application, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0068] The technical solution of the present application will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0069] Embodiment 1

[0070] This embodiment provides a dual-chamber cascaded acceleration-temperature sensor, as Figure 1 shown, including an acceleration sensor structure and a temperature sensor structure arranged up and down;

[0071] The acceleration sensor structure includes:

[0072] Side wall 11, with a cavity 14 formed in the middle;

[0073] Mass block 13, located in the middle of side wall 11, and the top and bottom surfaces of the mass block 13 are respectively coated with a first optical film 15;

[0074] Cantilever beam 12, connecting the mass block 13 and the side wall 11 to provide support for the mass block 13;

[0075] The temperature sensor structure includes:

[0076] Silicon-based material 22, arranged below the side wall 11, and the top and bottom surfaces of the silicon-based material 22 are respectively coated with a second optical film 23 and 24;

[0077] The transmittance and refractive index of the first optical film 15 and the second optical films 23 and 24 are equal.

[0078] The distance between the first optical film 15 below the mass block 13 and the second optical film on the top of the silicon-based material 22 is h1, the refractive index of the mass block 13 is n1, the distance between the second optical films on the top and bottom of the silicon-based material 22 is h2, the refractive index of the silicon-based material 22 is n2, and lg[h1*n1 / (h2*n2)] is less than 1, where lg is the common logarithm.

[0079] The silicon-based material 22 is in a concave shape, and the hollow part at the upper end forms an air cavity with the cavity 14, and the top of the silicon-based material 22 is located at the top of the hollow part;

[0080] The mass block 13 and the first optical films 15 on its top and bottom surfaces form a first-stage F-P cavity optical structure, and the silicon-based material 22 and the second optical films 23 and 24 on its top and bottom surfaces form a second-stage F-P cavity optical structure. Since the light of the second-stage F-P cavity optical structure comes from the light emitted from the first-stage F-P cavity optical structure, the wavelength ranges occupied by the two F-P cavities overlap.

[0081] Above the air cavity formed by the cavity 14 is an inertial motion structure composed of the cantilever beam 12 - mass block 13 combination. When the sensor is subjected to an acceleration parallel to the direction of the air cavity, the mass block 13 generates a displacement ( Figure 1 the up-and-down displacement in Figure 2 ) due to the influence of inertia, which further causes a change in the air cavity length, thereby causing a wavelength shift in the interference spectrum. The silicon cavity formed by the silicon-based material 22 is composed of single-crystalline silicon, and its upper and lower surfaces have optical films. When the external temperature changes, the volume of silicon changes accordingly (the air cavity is insensitive to temperature changes), which leads to a change in the silicon cavity length, thereby causing a wavelength shift in the interference spectrum. The product of the refractive index n and the cavity length h (nh) of the air cavity and the silicon cavity differs by more than one order of magnitude. As

[0082] shown, the cavity length of the air cavity is h1, and the cavity length of the silicon cavity is h2. The light beam is vertically incident from above the sensor mass block 13, passes through the air cavity and the silicon cavity, and then exits. The exiting light carries the wavelength shift information caused by the changes in the cavity lengths of the air cavity and the silicon cavity. By demodulating the exiting light, the acceleration and temperature can be measured simultaneously. Figure 3 shown.

[0083] Furthermore, the acceleration sensor structure and the temperature sensor structure are bonded by BCB glue, that is, the top of the silicon-based material 22 and the side wall 11 are bonded by BCB glue.

[0084] The acceleration sensor structure is fabricated from a SOI wafer. The SOI wafer has a five-layer structure, namely the first silicon layer, the first silicon oxide layer, the second silicon layer, the second silicon oxide layer, and the third silicon layer. The multi-layer structure facilitates the control of the lithography thickness.

[0085] Embodiment 2

[0086] This embodiment provides a preparation method for a dual-cavity cascaded acceleration-temperature sensor, for preparing the dual-cavity cascaded acceleration-temperature sensor of Embodiment 1, including:

[0087] Steps for fabricating the acceleration sensor structure, as Figure 4 shown:

[0088] S11: Take an SOI wafer 7. The shown SOI wafer 7 has a five-layer structure, namely a first silicon layer 71, a first silicon oxide layer 72, a second silicon layer 73, a second silicon oxide layer 74, and a third silicon layer 75;

[0089] S12: Coat photoresist 9 on the top of the first silicon layer 71, leave the corresponding area of the mass 13 to be processed blank, then deposit a metal layer and clean the photoresist to form the first optical film 15 on the top of the mass 13;

[0090] S13: Coat photoresist 9 on the bottom of the third silicon layer 75, leave the area between the mass 13 and the sidewall 11 blank, and etch the area between the mass 13 and the sidewall 11;

[0091] S14: Remove the photoresist 9 corresponding to the bottom of the third silicon layer 75 of the mass 13, and etch from the bottom of the third silicon layer 75 to form the mass 13 with the required thickness;

[0092] S15: Coat photoresist on the surface of the SOI wafer 7 except for the area of the mass 13 from the bottom after the process of step S14. After depositing a metal layer on the bottom surface of the mass 13, clean the photoresist to form the first optical film 15 on the bottom of the mass 13;

[0093] S16: Coat photoresist 9 on the surface of the corresponding areas of the cantilever beam 12 and the sidewall 11 in the SOI wafer 7 after the process of step S15 from the top. Etch the SOI wafer 7 from the top to form the cantilever beam 12 (etch away the substances between the cantilever beam 12, the mass 13, and the sidewall 11 to make the cantilever beam 12 suspended), and clean the photoresist to complete the preparation of the acceleration sensor structure;

[0094] Steps for preparing the temperature sensor structure are as Figure 5 shown:

[0095] S21: Take a silicon wafer 8. Coat photoresist on the top surface of the silicon wafer 8 except for the hollow part, and etch the silicon wafer 8 to make the whole silicon wafer form a concave-shaped structure, and clean the photoresist;

[0096] S22: Coat photoresist on the top surface of the silicon wafer 8 except for the corresponding area of the second optical film on the top of the silicon-based material 22. Then deposit a metal layer on the top surface of the silicon wafer 8 and clean the photoresist to form the second optical film on the top of the silicon-based material 22;

[0097] S23: Coat photoresist on the bottom surface of the silicon wafer 8 except for the corresponding area of the second optical film on the bottom of the silicon-based material 22. Then deposit a metal layer on the bottom surface of the silicon wafer 8 and clean the photoresist to form the second optical film on the bottom of the silicon-based material 22 to complete the preparation of the temperature sensor structure;

[0098] Combination steps:

[0099] Bond the bottom of the acceleration sensor structure to the top of the side wall 11 of the temperature sensor structure.

[0100] Furthermore, before the bonding step, bond bumps 76 are bonded to the top of the acceleration sensor structure to prevent damage to the mass block during the bonding step. After the bonding step, the bumps 76 can be etched away or retained.

[0101] Furthermore, the acceleration sensor structure and the temperature sensor structure are bonded by BCB glue, that is, the top of the silicon-based material 22 is bonded to the side wall 11 by BCB glue. The bonding is carried out in a vacuum environment.

[0102] Effect embodiment

[0103] In this embodiment, the dual-cavity cascaded acceleration-temperature sensor of Embodiment 1 is used for simulation testing. According to the free spectral range (FSR) and full width at half maximum (FWHM) formulas, when the nh (product of refractive index and cavity length) of the air cavity and the silicon cavity is close, its transmission spectrum is as Figure 6 .

[0104] At this time, it is difficult to separate the air cavity spectrum and the silicon cavity spectrum from the cascaded spectrum superimposed by the two cavities. Therefore, the acceleration and temperature information cannot be directly obtained by demodulating the output light spectrum.

[0105] When the difference in nh between the air cavity and the glass cavity exceeds one order of magnitude (10^1), a phenomenon similar to an "envelope" occurs in the cascaded spectrum of the output light, as Figure 7 shown.

[0106] When the sensor is affected by external acceleration, causing inertial displacement of the mass block on the upper side of the air cavity, the air cavity spectrum undergoes a wavelength shift, and the phenomenon reflected in the cascaded spectrum is that the "envelope" shifts, as Figure 8 shown.

[0107] The change in the air cavity length caused by acceleration only results in a wavelength shift of the envelope line, and the spectral lines inside the envelope do not shift. Therefore, the acceleration information can be obtained by demodulating the wavelength shift of the envelope line.

[0108] When the sensor is affected by external temperature, causing the silicon cavity to expand / contract and resulting in a change in cavity length, the silicon cavity spectrum undergoes a wavelength shift, and the phenomenon reflected in the cascaded spectrum is that the spectral lines inside the envelope shift, as Figure 9 shown.

[0109] The change in the air cavity length caused by temperature only results in a wavelength shift of the spectral lines inside the envelope, and the envelope line does not shift. Therefore, the temperature information can be obtained by demodulating the wavelength shift of the envelope line.

[0110] Inspired by the above-described ideal embodiments of the present application, through the above description, relevant staff can completely make various changes and modifications without departing from the technical idea of this application. The technical scope of this application is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A dual-chamber cascaded acceleration-temperature sensor, characterized in that, It includes an acceleration sensor structure and a temperature sensor structure arranged vertically. The acceleration sensor structure includes: Side walls (11) with a cavity (14) formed in the middle; A mass block (13) located in the middle of the side walls (11), and first optical films (15) are respectively plated on the top and bottom surfaces of the mass block (13); Cantilever beams (12) connecting the mass block (13) and the side walls (11) to provide support for the mass block (13); The temperature sensor structure includes: A silicon-based material (22) arranged below the side walls (11), and second optical films (23, 24) are respectively plated on the top and bottom of the silicon-based material (22); The transmittance and refractive index of the first optical film (15) and the second optical films (23, 24) are equal, and the distance between the first optical film (15) below the mass block (13) and the second optical film on the top of the silicon-based material (22) is h1, the refractive index of the mass block (13) is n1, the distance between the second optical films on the top and bottom of the silicon-based material (22) is h2, the refractive index of the silicon-based material (22) is n2, and lg[h1*n1 / (h2*n2)] is less than 1, where lg is the common logarithm; The silicon-based material (22) is in a concave shape, the hollow part at the upper end forms an air cavity with the cavity (14), the top of the silicon-based material (22) is at the top of the hollow part, and the light beam is vertically incident from above the sensor mass block (13).

2. The dual - cavity cascaded acceleration - temperature sensor according to claim 1, characterized in that, The acceleration sensor structure and the temperature sensor structure are bonded by BCB glue.

3. The dual-chamber cascaded acceleration-temperature sensor according to claim 1, characterized in that, The acceleration sensor structure is prepared from an SOI wafer.

4. The dual-chamber cascaded acceleration-temperature sensor according to claim 3, wherein, The SOI wafer has a 5-layer structure, namely the first silicon layer, the first silicon oxide layer, the second silicon layer, the second silicon oxide layer, and the third silicon layer.

5. A preparation method of a dual-cavity cascaded acceleration-temperature sensor for preparing the dual-cavity cascaded acceleration-temperature sensor according to claim 1, including: Steps for preparing the acceleration sensor structure: S11: Take an SOI wafer with a layer structure including the first silicon layer, the first silicon oxide layer, the second silicon layer, the second silicon oxide layer, and the third silicon layer; S12: Coat photoresist on the top of the first silicon layer, leave the corresponding area of the mass block to be processed blank, then deposit a metal layer and clean the photoresist to form the first optical film on the top of the mass block; S13: Coat photoresist on the bottom of the third silicon layer, leave the area between the mass block and the side walls blank, and etch the area between the mass block and the side walls; S14: Remove the photoresist corresponding to the bottom of the third silicon layer of the mass block, and etch from the bottom of the third silicon layer to form the mass block with the required thickness; S15: Coat photoresist on the surface of the SOI wafer except for the mass block area processed in step S from the bottom, deposit a metal layer on the bottom surface of the mass block and then clean the photoresist to form the first optical film on the bottom of the mass block; S16: Coat photoresist on the surface of the SOI wafer corresponding to the cantilever beams and side walls from the top, etch the SOI wafer from the top to form the cantilever beams, and wash off the photoresist to complete the preparation of the acceleration sensor structure; Steps for preparing the temperature sensor structure: S21: Take a silicon wafer, coat photoresist on the top surface of the silicon wafer except for the hollow part, etch the silicon wafer to form a concave-shaped structure on the whole silicon wafer, and clean the photoresist. S22: On the top surface of the silicon wafer, coat photoresist except for the corresponding area of the second optical film on the top of the silicon-based material. Then deposit a metal layer on the top surface of the silicon wafer and clean the photoresist to form the second optical film on the top of the silicon-based material. S23: On the bottom surface of the silicon wafer, coat photoresist except for the corresponding area of the second optical film on the bottom of the silicon-based material. Then deposit a metal layer on the bottom surface of the silicon wafer and clean the photoresist to form the second optical film on the bottom of the silicon-based material, completing the preparation of the temperature sensor structure. Combining step: Bond the bottom of the acceleration sensor structure to the top of the temperature sensor structure.

6. The manufacturing method of the dual-chamber cascaded acceleration-temperature sensor according to claim 5, characterized in that, Before performing the combining step, bond bumps (76) on the top of the acceleration sensor structure.

7. The manufacturing method of the double-chamber cascaded acceleration-temperature sensor according to claim 5, characterized in that, The acceleration sensor structure and the temperature sensor structure are bonded by BCB glue.

8. The manufacturing method of the dual-chamber cascaded acceleration-temperature sensor according to claim 7, characterized in that The bonding process is carried out in a vacuum environment.

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