High-temperature-resistant micro-nano film temperature sensor based on metal substrate and manufacturing method thereof

Abstract

The application relates to a high-temperature-resistant metal-substrate-based micro-nano film temperature sensor and a manufacturing method, and belongs to the technical field of sensors. The sensor mainly comprises a metal base, a bonding layer, a first insulating layer, a second insulating layer, a first pole sensing layer, a second pole sensing layer, a third insulating layer, a fourth insulating layer, a conductive seed layer, a protective layer and a wire. The manufacturing steps are as follows: 1) depositing the bonding layer on the metal base; depositing the first insulating layer and the second insulating layer on the surface of the bonding layer; 2) manufacturing the first pole sensing layer and the second pole sensor; 3) depositing the third insulating layer and the fourth insulating layer; 4) sequentially depositing the bonding layer and the conductive seed layer on the surface of the fourth insulating layer; and 5) depositing the protective layer on the seed layer, so as to form a sandwiched layered packaging structure. The application is suitable for local multi-point dynamic temperature detection under a 1000 DEG C high-temperature environment, and compared with a traditional filament thermocouple, the application has the outstanding technical features of small size, fast response, high precision and good protection.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of sensors and relates to a high-temperature-resistant micro-nano film temperature sensor based on a metal substrate and a manufacturing method. BACKGROUND

[0002] Temperature detection is often carried out in modern industrial production and scientific research processes. Traditional armored thermocouples or thermal resistors are difficult to apply in some scenes with strict installation space size limitations and dramatic instantaneous dynamic changes due to their large size, slow response and other shortcomings. Even if they are used, their accuracy, reliability, timeliness and durability are greatly compromised. SUMMARY

[0003] Therefore, the application aims to provide a high-temperature-resistant micro-nano film temperature sensor based on a metal substrate and a manufacturing method.

[0004] To achieve the above-mentioned purpose, the application provides the following technical solutions.

[0005] A high-temperature-resistant micro-nano film temperature sensor based on a metal substrate mainly comprises a metal substrate, a bonding layer, a first insulating layer, a second insulating layer, a first electrode sensing layer, a second electrode sensing layer, a third insulating layer, a fourth insulating layer, a conductive seed layer, a protective layer, a sensor pad and a wire.

[0006] The bonding layer, the first insulating layer and the second insulating layer are sequentially deposited on the metal substrate.

[0007] Further, the deposition method mainly includes electroplating, spin coating, photolithography, magnetron sputtering, electron beam evaporation and atomic layer deposition.

[0008] The bonding layer and the first electrode sensing layer are sequentially deposited on the second insulating layer.

[0009] A plurality of thermocouple circuits are integrated on the first electrode sensing layer.

[0010] Further, the two-pole material of the thermocouple circuit includes NiCr-NiAlMnSi, NiCr-NiAl and / or NiCr-NiSi alloy.

[0011] The first electrode sensing layer has a sensor pad connected with a wire.

[0012] The bonding layer and the second electrode sensing layer are sequentially deposited on the first electrode sensing layer.

[0013] A plurality of thermocouple circuits are integrated on the second electrode sensing layer.

[0014] The second electrode sensing layer has a sensor pad connected with a wire. Further, the sensor pad is exposed.

[0015] A bonding layer, a third insulating layer, a fourth insulating layer, a bonding layer and a conductive seed layer are sequentially deposited on the second electrode sensing layer.

[0016] A protective layer is deposited on the conductive seed layer.

[0017] One end of the wire is connected to the sensor pad.

[0018] Further, the conductive seed layer has a thickness ranging from 10nm to 100nm, the bonding layer has a thickness ranging from 10nm to 100nm, the first insulating layer has a thickness ranging from 500nm to 1500nm, the second insulating layer has a thickness ranging from 20nm to 100nm, the third insulating layer has a thickness ranging from 750nm to 1800nm, the fourth insulating layer has a thickness ranging from 20nm to 100nm, and the sensing layer has a thickness ranging from 300nm to 900nm.

[0019] The materials of the first insulating layer, the second insulating layer, the third insulating layer and the fourth insulating layer are oxide ceramics.

[0020] The material of the bonding layer is metal chromium.

[0021] The materials of the first electrode sensing layer and the second electrode sensing layer are nickel-based alloys.

[0022] The material of the conductive seed layer is metal nickel.

[0023] The material of the protective layer is metal nickel.

[0024] The material of the wire is conductive silver glue.

[0025] A manufacturing method of a high-temperature micro-nano thin film temperature sensor based on a metal substrate, mainly comprising the following steps:

[0026] 1) Design the shape, size and number of the sensor based on the temperature detection range, and manufacture the high-temperature micro-nano thin film temperature sensor.

[0027] 2) Select the metal substrate of the high-temperature micro-nano thin film temperature sensor, and deposit a bonding layer on the metal substrate.

[0028] 3) Deposit a first insulating layer on the surface of the bonding layer by using an electron beam evaporation process, and deposit a second insulating layer on the first insulating layer by using an atomic layer deposition process.

[0029] 4) Apply a layer of photoresist on the surface of the second insulating layer by using a spin coating process.

[0030] 5) Pre-baking the metal substrate with the adhesion layer, the first insulation layer, the second insulation layer and the photoresist on the hot plate. Exposing the pre-baked metal substrate on the photoetching machine with the mask plate. Post-baking the exposed metal substrate on the hot plate and developing it in the developing solution.

[0031] 6) Depositing the adhesion layer, the first pole sensing layer and the adhesion layer on the surface of the photoresist layer in sequence by the magnetron sputtering process; the first pole sensing layer has the sensor pads connected with the wires;

[0032] 7) Depositing the second pole sensing layer and the adhesion layer on the surface of the adhesion layer in sequence; the second pole sensing layer has the sensor pads connected with the wires; soaking the metal substrate in the acetone to strip the photoresist; cleaning and drying the metal substrate after stripping;

[0033] 8) Depositing the third insulation layer on the surface of the adhesion layer above the second pole sensing layer by the electron beam evaporation process. Depositing the fourth insulation layer on the first insulation layer by the atomic layer deposition process.

[0034] 9) Depositing the adhesion layer and the conductive seed layer on the surface of the fourth insulation layer in sequence by the magnetron sputtering process.

[0035] 10) Depositing the protective layer on the seed layer by the electroplating process, thereby forming the sandwich layered packaging structure.

[0036] 11) Removing the insulation layer on the surface of the sensor pads by the plasma etching process.

[0037] 12) Connecting the wires with the sensor pads and baking and curing them by the hot plate. After baking and curing, applying a layer of epoxy resin on the sensor pads and curing them for t hours, thereby forming the micro-nano thin film temperature sensor.

[0038] Further, the time range of t is 10-36 hours.

[0039] It is worth noting that the design of the sensing layer is based on the K-type thermocouple principle, two different nickel-based alloys are used as the two pole materials of the thermocouple loop, and the temperature value of the hot end of the detection point is obtained by reading the thermoelectric power signal; multiple thermocouple loops can be deposited on the sensing layer of the same substrate to realize multi-point detection in a narrow local area, the spatial resolution is high, and even if one detection point is damaged, the remaining detection points can still work normally, and the detection redundancy is good; the sensor film thickness is only a few hundred nanometers, the line width and hot junction size are small, the mass and heat capacity are small, the response to rapid changes in the temperature field is fast, the response time can reach microseconds, and the interference damage to the real temperature field of the detection point is small.

[0040] The technical effect of the present application is self-evident, the present application discloses a kind of high-temperature-resistant micro-nano film temperature sensor based on metal substrate and manufacturing method thereof, it is suitable for local multi-point dynamic temperature detection under 1000 ℃ high-temperature environment, compared with traditional filament thermocouple, with Small size, fast response, high precision, good protection and other outstanding technical features, especially suitable for the detection scene of strict installation size limit and transient temperature field violent change, can be widely applied in aerospace, precision machine tool processing, national defense and military industry, metallurgical manufacturing and other fields.

[0041] The micro-nano film sensor disclosed in the present application has small size, fast response, and small disturbance to original temperature field, can timely and accurately capture the instantaneous dynamic change of temperature field, can be flexibly and conveniently installed in narrow space and closer to detection point for detection, can arrange multiple thermocouple circuits at one detection point according to demand to realize local multi-point detection;The packaging mode based on the metal substrate with relatively high melting point hardness and good corrosion resistance makes the sensor have good high-temperature and high-pressure resistance and anti-interference performance, which can effectively guarantee the use effect of the sensor in harsh industrial environment, and help to greatly improve its service life.

[0042] Other advantages, objects and features of the present application will be described in the following specification to some extent, and to some extent, it will be obvious to those skilled in the art based on the study of the following, or can be taught from the practice of the present application. The objects and other advantages of the present application can be achieved and obtained by the following specification. BRIEF DESCRIPTION OF DRAWINGS

[0043] In order to make the purpose, technical scheme and advantages of the present application more clear, the preferred detailed description of the present application will be described below in combination with the drawings, in which:

[0044] Figure 1 The schematic diagram for micro-nano film temperature sensor is designed;

[0045] Figure 2 The structure schematic diagram of the substrate after sputtering chromium adhesive layer is completed;

[0046] Figure 3 The structure schematic diagram of the substrate after completing deposition of bottom insulating layer;

[0047] Figure 4 The structure schematic diagram of the substrate after completing deposition of top insulating layer;

[0048] Figure 5 The structure schematic diagram of the substrate after sputtering chromium adhesive layer and nickel conductive seed layer is completed;

[0049] Figure 6 The schematic diagram of exposure & development process step;

[0050] Figure 7 Schematic diagram for sputtering deposition of metal sensing layer;

[0051] Figure 8 Schematic diagram for completing deposition of two-pole sensing loop;

[0052] Figure 9 Schematic diagram for forming sandwich packaging structure after plating metal protective layer;

[0053] Figure 10 Schematic diagram for core working layer of micro-nano thin film temperature sensor.

[0054] The figure marks are as follows: 1-metal substrate, 2-adhesion layer, 301-first insulation layer, 302-second insulation layer, 4-photoresist, 501-first pole sensing layer, 502-second pole sensing layer, 601-third insulation layer, 602-fourth insulation layer, 8-conductive seed layer, 9-protective layer, 10-sensor pad, 11-conductive wire, A-sensor cathode, B-sensor anode, T0-lower end temperature sensing contact, T-upper end temperature sensing contact. DETAILED DESCRIPTION

[0055] The embodiments of the present application will be described in detail with specific examples, and other advantages and effects of the present application can be easily understood by those skilled in the art from the disclosure of the present specification. The present application can also be implemented or applied by other different specific embodiments, and each detail in the present specification can be modified or changed based on different views and applications without departing from the spirit of the present application. It should be noted that the drawings provided in the following examples only schematically illustrate the basic concept of the present application, and the following examples and features in the examples can be combined with each other without conflict.

[0056] It should be noted that the drawings provided in the following examples only schematically illustrate the basic concept of the present application, and the following examples and features in the examples can be combined with each other without conflict.

[0057] The same or similar reference numerals in the drawings of the embodiments of the present application correspond to the same or similar components; in the description of the present application, it is understood that if the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "front", "back", etc. are based on the orientations or positional relationships shown in the drawings, they are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or components referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore the terms describing the positional relationships in the drawings are only used for exemplary illustration and cannot be understood as a limitation on the present application, for those skilled in the art, the specific meanings of the above terms can be understood according to the specific circumstances.

[0058] Embodiment 1:

[0059] Please refer to Figures 1 to 10 , it is a kind of high-temperature-resistant micro-nano film temperature sensor based on metal substrate, mainly including metal base (1), bonding layer (2), first insulating layer (301), second insulating layer (302), first pole sensing layer (501), second pole sensing layer (502), third insulating layer (601), fourth insulating layer (602), conductive seed layer (8), protective layer (9), sensor pad (10) and wire (11).

[0060] The bonding layer (2), the first insulating layer (301) and the second insulating layer (302) are sequentially deposited on the metal base (1).

[0061] Further, the deposition method mainly includes electroplating, spin coating, photolithography, magnetron sputtering, electron beam evaporation and atomic layer deposition.

[0062] The bonding layer (2) and the first pole sensing layer (501) are sequentially deposited on the second insulating layer (302).

[0063] The first pole sensing layer (501) is integrated with several thermocouple loops.

[0064] Further, the two-pole material of thermocouple loop includes NiCr-NiAlMnSi, NiCr-NiAl and / or NiCr-NiSi alloy.

[0065] The first pole sensing layer (501) has sensor pad (10) connected with wire (11).

[0066] The bonding layer (2) and the second pole sensing layer (502) are sequentially deposited on the first pole sensing layer (501).

[0067] The second pole sensing layer (502) is integrated with several thermocouple loops to realize multi-point detection in narrow local area.

[0068] The second electrode sensing layer (502) has a sensor pad (10) connected with a connecting wire (11). Further, the sensor pad (10) is exposed.

[0069] A bonding layer (2), a third insulating layer (601), a fourth insulating layer (602) and a conductive seed layer (8) are sequentially deposited on the second electrode sensing layer (502).

[0070] A protective layer (9) is deposited on the conductive seed layer (8).

[0071] One end of the connecting wire (11) is connected with the sensor pad (10).

[0072] Further, the thickness of the conductive seed layer (8) ranges from 10 nm to 100 nm, the thickness of the bonding layer (2) ranges from 10 nm to 100 nm, the thickness of the first insulating layer (301) ranges from 500 nm to 1500 nm, the thickness of the second insulating layer (302) ranges from 20 nm to 100 nm, the thickness of the third insulating layer (601) ranges from 750 nm to 1800 nm, the thickness of the fourth insulating layer (602) ranges from 20 nm to 100 nm, and the thickness of the first electrode sensing layer (501) and the second electrode sensing layer (502) ranges from 300 nm to 900 nm.

[0073] The materials of the first insulating layer (301), the second insulating layer (302), the third insulating layer (601) and the fourth insulating layer (602) are oxide ceramics.

[0074] The material of the bonding layer (2) is metal chromium.

[0075] The materials of the first electrode sensing layer (501) and the second electrode sensing layer (502) are nickel-based alloys.

[0076] The material of the conductive seed layer (8) is metal nickel.

[0077] The material of the protective layer (9) is metal nickel.

[0078] The material of the connecting wire (11) is conductive silver glue.

[0079] Embodiment 2:

[0080] A manufacturing method of a high-temperature micro-nano thin film temperature sensor based on a metal substrate mainly includes the following steps:

[0081] 1) Based on the temperature detection range, the shape, size and number of the sensor are designed, and a high-temperature resistant micro-nano thin film temperature sensor is manufactured.

[0082] 2) A metal substrate (1) of a high-temperature resistant micro-nano thin film temperature sensor is selected, and a bonding layer (2) is deposited on the metal substrate (1).

[0083] The metal substrate (1) is grinded and chemically mechanically polished, and the surface roughness is controlled at 100-400 nm.

[0084] 3) A first insulating layer (301) is deposited on the surface of the adhesive layer (2) by using an electron beam evaporation process. A second insulating layer (302) is deposited on the first insulating layer (301) by using an atomic layer deposition process.

[0085] The adhesive layer (2) can effectively enhance the adhesion between the substrate and the insulating layer and between the sensing layer and the insulating layer, and prevent delamination.

[0086] Further, the ceramic material with high melting point, high hardness and good dielectric property is used as the insulating layer, and the temperature detection under the environment of 1000℃ can be reliably realized.

[0087] 4) A photoresist (4) is coated on the surface of the second insulating layer (302) by using a spin coating process.

[0088] The second insulating layer (302) can fill the possible pits of the first insulating layer (301) to realize a completely dense structure.

[0089] 5) The metal substrate (1) with the adhesive layer (2), the first insulating layer (301), the second insulating layer (302) and the metal substrate (1) is pre-baked on a hot plate. The metal substrate (1) after pre-baking is exposed to light by using a mask plate on a photoetching machine. After exposure, the metal substrate (1) is placed on a hot plate for post-baking, and then is placed in a developing solution for development.

[0090] 6) The adhesive layer (2), the first sensing layer (501) and the adhesive layer (2) are sequentially deposited on the surface of the photoresist layer by using a magnetron sputtering process; the first sensing layer (501) has a sensor pad (10) connected to a lead wire (11);

[0091] 7) The second sensing layer (502) and the adhesive layer (2) are sequentially deposited on the surface of the adhesive layer (2); the second sensing layer (502) has a sensor pad (10) connected to a lead wire (11); the metal substrate (1) is placed in acetone for soaking to strip the photoresist (4); after stripping, the metal substrate (1) is cleaned and dried.

[0092] 8) A third insulating layer (601) is deposited on the surface of the adhesive layer (2) above the second sensing layer (502) by using an electron beam evaporation process. A fourth insulating layer (602) is deposited on the first insulating layer (301) by using an atomic layer deposition process.

[0093] The fourth insulating layer (602) can fill the possible pits of the third insulating layer (601) to realize a completely dense structure.

[0094] 9) A layer of adhesive layer (2) and a layer of conductive seed layer (8) are deposited on the surface of the fourth insulating layer (602) by magnetron sputtering process.

[0095] 10) A layer of protective layer (9) is deposited on the conductive seed layer (8) by electroplating process, thereby forming a sandwich layered packaging structure.

[0096] Further, the sensor uses a metal with good electrical conductivity and thermal conductivity, high melting point and hardness as the protective layer.

[0097] 11) The insulating layer on the surface of the sensor pad (10) is removed by plasma etching process.

[0098] 12) The sensor pad (10) is connected to the lead wire (11), and is baked and cured by a hot plate. After baking and curing, a layer of epoxy resin is applied on the sensor pad, and is cured for t hours, thereby forming a micro-nano thin film temperature sensor.

[0099] Further, the time range of t is 10-36 hours.

[0100] Example 3:

[0101] Based on the classic Seebeck effect and K-type thermocouple principle, a micro-nano thin film temperature sensor with typical sandwich layered packaging structure and capable of withstanding 1000°C high temperature is made in a super-clean room by MEMS micro-electro-mechanical processing technologies such as uniform glue spin coating, photoetching and developing, magnetron sputtering, electron beam evaporation, and atomic layer deposition, using a metal with relatively high melting point and hardness, good thermal and electrical conductivity as the substrate. The manufacturing method mainly includes the following steps:

[0102] 1) According to the requirements of temperature detection, a micro-nano thin film temperature sensor is designed and manufactured, including the shape, size and number of the sensor, as shown in Figure 1 .

[0103] 2) A metal with a diameter of 4" and a thickness of 50-800 μm is used as the substrate for sensor deposition. After grinding and chemical mechanical polishing, a layer of chromium adhesive layer with a thickness of 10-100 nm is deposited on the surface by magnetron sputtering process, as shown in Figure 2 .

[0104] 3) Two layers of oxide ceramic material insulating layer are deposited on the surface of the adhesive layer by electron beam evaporation process and atomic layer deposition process, respectively. The first layer has a thickness of 500-1500 nm, and the second layer has a thickness of 20-100 nm, as shown in Figure 3 .

[0105] 4) Through the uniform glue spin coating process on the surface of the insulating layer is coated with a thickness of 1 μm ~ 5 μm photoresist, and on the hot plate for the front baking, then on the photoetching machine using mask plate for exposure, after the completion of the placement in the hot plate for the post baking, then placed in the developer for development, after cleaning and drying will form the sensor shape and size of the mask, see Figure 6 .

[0106] 5) Through the magnetron sputtering process on the surface of the photoresist layer is deposited in turn three layers of metal, respectively, the thickness of 10 nm ~ 100 nm of metal chromium, thickness of 300 nm ~ 900 nm of nickel base alloy and thickness of 10 nm ~ 100 nm of metal chromium, form the first pole sensor circuit, see Figure 7 .

[0107] 6) in turn another pole nickel base alloy, metal chromium deposition, and form the second pole sensor circuit, then placed in the acetone for soaking to strip the photoresist, and after cleaning and drying, see Figure 8 .

[0108] 7) through the electron beam evaporation process and atomic layer deposition process on the sensor layer is deposited in turn two layers of oxide ceramic material insulation layer, the first layer thickness of 750 nm ~ 1800 nm, the second layer thickness of 20 nm ~ 100 nm, at the same time just expose the pad part, see Figure 4 .

[0109] 8) through the magnetron sputtering process on the sensor layer above the surface of the insulating layer is deposited in turn a layer of thickness of 10 nm ~ 100 nm of metal chromium adhesive layer and thickness of 10 nm ~ 100 nm of metal nickel conductive seed layer, see Figure 5 .

[0110] 9) through the electroplating process on the conductive seed layer is deposited a layer of thickness of 50 μm ~ 800 μm of metal nickel protective layer, and form the final sandwich layer packaging structure, see Figure 9 .

[0111] 10) using conductive silver glue on all the pads of the sensor layer connecting compensation wire, after the hot plate baking and curing, then daub a layer of epoxy resin, after 10 hours ~ 36 hours of aging curing, the whole sensor is completed, which detects the temperature by collecting potential signal, the sensor layer is its core working layer, see Figure 10 .

[0112] Example 4:

[0113] A kind of high temperature resistant micro-nano film temperature sensor based on metal substrate manufacturing method, mainly includes the following steps:

[0114] 1) First, based on the requirements for temperature detection, a micro / nano film temperature sensor is designed, such as... Figure 1 As shown, this includes the shape, size, and quantity of the sensor. The sensor design is based on the Seebeck effect thermoelectric principle, where two different conductors act as the anode and cathode, respectively, with their ends tightly connected to form a closed loop. When the temperatures of the two junctions are unequal (T > T0), an electromotive force is generated in the loop, thus forming a thermoelectric current. When the cold junction temperature is fixed, the thermoelectric potential is a single-valued function of the hot junction temperature T. The specific value of the hot junction temperature T can be determined based on the magnitude of the generated thermoelectric potential. The sensor uses a type K thermocouple, and a type K thermocouple alloy is selected as the sensing layer. Multiple sets of sensors are arranged on the substrate according to requirements, and each set of sensors can accommodate multiple pairs of thermocouple loops. The loop routing design should be as symmetrical and aesthetically pleasing as possible, and easy to cut and process. When considering the planar dimensions of the sensor, the success rate of sensor fabrication should also be taken into account; that is, the linewidth of a single electrode and the distance between each pair of electrodes should not be too small. In addition, to reduce the difficulty of lead connection and ensure insulation between each pair of pads, the side length of a single square pad and the distance between each pair of pads should not be too small.

[0115] 2) A 4” diameter, 50μm–800μm thick nickel-based alloy or stainless steel sheet is used as the substrate for sensor deposition. Nickel-based alloys have high melting point and hardness, good high-temperature mechanical strength and corrosion resistance, making them particularly suitable for harsh environments such as high temperature and corrosion. Choosing them as a protective layer is appropriate. After multi-stage grinding and chemical mechanical polishing, the substrate should be smooth and free of obvious scratches, pits and other defects. The surface roughness should be controlled within 100nm–400nm by white light interferometer testing.

[0116] 3) To enhance the adhesion between the metal substrate and the subsequent insulating layer, a 10nm–100nm thick chromium layer needs to be deposited on the substrate surface using magnetron sputtering as a bonding layer, such as… Figure 2 As shown, if the substrate surface is relatively rough, the deposition thickness can be appropriately increased. Sputtering involves bombarding the surface of a solid target with plasma carrying kinetic energy of tens of electron volts or more. Atoms near the surface gain some of the energy carried by the incident particles; when this energy is sufficient to overcome the binding energy, these atoms detach from the solid and enter the vacuum chamber, subsequently depositing onto the substrate. Specific sputtering process parameters are: sputtering power 200W–600W, sputtering rate 10nm / min–20nm / min, and sputtering time 2min–6min. Of course, these parameters may be adjusted for different equipment platforms.

[0117] 4) Next, the bottom insulating layer needs to be made. First, an oxide ceramic material with a thickness of 500 nm to 1000 nm is deposited on the surface of the chromium adhesive layer as the first insulating layer by electron beam evaporation process. Electron beam evaporation is a physical vapor deposition method that precisely realizes the use of high-energy electrons to bombard the target material, causing it to melt and deposit on the substrate object by using electromagnetic fields. To ensure that the insulating layer is uniform and dense, another layer of oxide ceramic material with a thickness of 20 nm to 100 nm is then deposited as the second insulating layer by atomic layer deposition process. Atomic layer deposition is a method similar to chemical vapor deposition, in which gas phase precursor pulses are alternately injected into the reactor, which undergoes chemical adsorption and reaction when reaching the surface of the substrate object, and then deposits layer by layer in the form of a single-atom film. The resistance between the two layers of chromium on the insulating layer should be ensured to reach the order of megohm.

[0118] 5) In order to produce the designed sensor pattern to carry out the next step of sputter deposition of the metal sensing layer, a layer of photoresist with a thickness of 1 μm to 5 μm needs to be coated on the surface of the insulating layer by spin coating. Then, pre-baking is performed on the hot plate to remove the solvent in the photoresist and enhance adhesion. Next, the pre-baked substrate is placed on the photoetching machine for exposure. After exposure, the substrate is placed on the hot plate for post-baking to activate the acid generated by the PAG photosensitive acid generator in the chemically enhanced photoresist to react with the protective groups on the photoresist and remove the groups to enable dissolution in the developer, while reducing the standing wave effect. Subsequently, the post-baked substrate is placed in the developer for development. After development is complete, deionized water is used for cleaning, and nitrogen is used for drying, finally forming a pattern of the sensor shape and size, as shown in Figure 6 .

[0119] 6) Next, the most core metal sensing layer is started to be made. First, a layer of 10-100 nm thick metal chromium is sputtered according to the process method described in step 3). Then, a layer of nickel-based alloy with a thickness of 300 nm to 900 nm is deposited by magnetron sputtering, with specific sputtering process parameters of: sputtering power 200 W to 600 W, sputtering rate 10 nm / min to 20 nm / min, sputtering time 30 min to 80 min. Of course, for different equipment platforms, the parameters may be adjusted. Then, a layer of 10-100 nm thick metal chromium is sputtered according to the process method described in step 3), and the deposition of the first electrode sensing circuit on the substrate is completed, as shown in Figure 7 .

[0120] 7) Then sputtering deposition of another polar nickel-based alloy layer with a thickness of 300-900 nm, the specific sputtering process parameters are: sputtering power 200-600 W, sputtering rate 10-20 nm / min, sputtering time 30-80 min, of course, for different equipment platform, the parameters may be adjusted. Then sputtering deposition of a layer of 10-100 nm thick metal chromium. After deposition, immersion stripping, cleaning and drying, the second electrode sensing circuit is deposited on the substrate, as shown in Figure 8 . By this time, the most core sensing layer has been completed.

[0121] 8) Through electron beam evaporation process and atomic layer deposition process, two layers of oxide ceramic material insulation layer are deposited on the sensing layer in turn, the lower layer is 750-1800 nm thick, and the upper layer is 20-100 nm thick, and a template specially designed for the sensing layer pattern is used to ensure that the pad part is exposed after deposition, as shown in Figure 4 .

[0122] 9) The last step is to make a metal protective layer. First, a 10-100 nm thick metal chromium adhesion layer and a 10-100 nm thick metal nickel conductive seed layer are deposited on the surface of the top insulating layer by magnetron sputtering process, and a template specially designed for the sensing layer pattern is used to ensure that the pads remain exposed; then a 50-800 μm thick metal nickel protective layer is deposited on the conductive seed layer by electroplating process, and the final sandwich layer packaging structure is formed, as shown in Figure 5 . The specific electroplating process parameters are: watt plating solution plus brightener, current density 0.8-1.2 A / dm2, plating solution temperature 42-45°C, plating solution PH value 4.0-5.0; then conductive silver paste is used to connect the compensation wires on all the pads of the sensing layer, and after hot plate baking and curing, a layer of epoxy resin is applied, and after 10-36 hours of aging and curing, the entire sensor is completed, which detects temperature by collecting potential signals, and the sensing layer is the core working layer, as shown in Figure 10 .

[0123] The high-temperature micro-nano thin film sensor based on the metal substrate has small size, fast response, small interference to the original temperature field, can timely and accurately capture the instantaneous dynamic change of the temperature field, can be flexibly and conveniently installed in a small space and detected closer to a detection point, can arrange multiple thermocouple circuits at one detection point according to requirements to realize local multi-point detection, has good high-temperature and high-pressure resistance, anti-interference and corrosion resistance due to the sandwich layer packaging structure of the metal nickel-based alloy or stainless steel substrate with relatively high melting point and good corrosion resistance, can effectively avoid wear and corrosion, can effectively guarantee the use effect of the thin film sensor in a harsh industrial environment, and can help to greatly improve the durability and service life of the thin film sensor. The application can significantly improve the technical limitations and disadvantages of the conventional temperature detection assembly in space size, dynamic response and packaging protection, provides an important hardware foundation and technical means for the optimization and innovation of the conventional temperature detection mode, and is worth popularizing and applying in various temperature detection fields.

[0124] Finally, it should be pointed out that the above embodiments are only used to illustrate the technical solutions of the application and not to limit the application, although the application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the application can be modified or replaced by equivalents without departing from the purpose and scope of the technical solutions, which should be covered in the scope of the claims of the application.

Claims

1. A high temperature resistant micro-nano thin film temperature sensor based on a metal substrate, characterized in that: The micro-nano thin film temperature sensor comprises a metal substrate (1), a bonding layer, a first insulating layer (301), a second insulating layer (302), a first electrode sensing layer (501), a second electrode sensing layer (502), a third insulating layer (601), a fourth insulating layer (602), a conductive seed layer (8), a protective layer (9), a sensor pad (10) and a lead wire (11). ​ The bonding layer, the first insulating layer (301) and the second insulating layer (302) are sequentially deposited on the metal substrate (1). The bonding layer and the first electrode sensing layer (501) are sequentially deposited on the second insulating layer (302). A plurality of thermocouple loops are integrated on the first electrode sensing layer (501). The sensor pad (10) connected with the lead wire (11) is provided on the first electrode sensing layer (501). The bonding layer and the second electrode sensing layer (502) are sequentially deposited on the first electrode sensing layer (501). A plurality of thermocouple loops are integrated on the second electrode sensing layer (502). The sensor pad (10) connected with the lead wire (11) is provided on the second electrode sensing layer (502). The bonding layer, the third insulating layer (601), the fourth insulating layer (602), the bonding layer and the conductive seed layer (8) are sequentially deposited on the second electrode sensing layer (502). The protective layer (9) is deposited on the conductive seed layer (8). One end of the lead wire (11) is connected with the sensor pad (10).

2. The micro-nano thin film temperature sensor according to claim 1, wherein: The thickness of the conductive seed layer (8) ranges from 10 nm to 100 nm. The thickness of the bonding layer ranges from 10 nm to 100 nm. The thickness of the first insulating layer (301) ranges from 500 nm to 1500 nm. The thickness of the second insulating layer (302) ranges from 20 nm to 100 nm. The thickness of the third insulating layer (601) ranges from 750 nm to 1800 nm. The thickness of the fourth insulating layer (602) ranges from 20 nm to 100 nm. The thickness of the first electrode sensing layer (501) and the second electrode sensing layer (502) ranges from 300 nm to 900 nm.

3. The micro- and nano-film temperature sensor of claim 1, wherein, The materials of the two poles of the thermocouple loop comprise NiCr-NiAlMnSi, NiCr-NiAl and / or NiCr-NiSi alloy.

4. The micro-nano thin film temperature sensor according to claim 1, wherein: The materials of the first insulating layer (301), the second insulating layer (302), the third insulating layer (601) and the fourth insulating layer (602) are oxide ceramic. The material of the bonding layer is chromium. The materials of the first electrode sensing layer (501) and the second electrode sensing layer (502) are nickel-based alloy. The material of the conductive seed layer (8) is nickel. The material of the protective layer (9) is nickel. The material of the lead wire (11) is conductive silver glue.

5. A method for making a high temperature resistant micro-nano thin film temperature sensor based on a metal substrate, characterized in that, The method comprises the following steps: Step 1: based on the temperature detection range, the shape, size and quantity of the sensor are designed, and a high-temperature-resistant micro-nano thin film temperature sensor is manufactured. Step 2, select a high-temperature-resistant metal substrate (1) for the micro-nano film temperature sensor, and deposit a bonding layer on the metal substrate (1); Step 3, deposit a first insulating layer (301) on the surface of the bonding layer by electron beam evaporation process; deposit a second insulating layer (302) on the first insulating layer (301) by atomic layer deposition process; Step 4, coat a layer of photoresist (4) on the surface of the second insulating layer (302) by spin coating process; Step 5, pre-bake the metal substrate (1) with the bonding layer, the first insulating layer (301), the second insulating layer (302) and the photoresist (4) on the hot plate; expose the pre-baked metal substrate (1) to light using a mask plate on the photoetching machine; After exposure, place the metal substrate on the hot plate for post-baking, and then place it in the developing solution for development; Step 6, deposit a bonding layer, a first electrode sensing layer (501) and a bonding layer on the surface of the photoresist layer in sequence by magnetron sputtering process; the first electrode sensing layer (501) has a sensor pad (10) connected to a lead wire (11); Step 7, deposit a second electrode sensing layer (502) and a bonding layer on the surface of the bonding layer in sequence; the second electrode sensing layer (502) has a sensor pad (10) connected to a lead wire (11); immerse the metal substrate (1) in acetone to remove the photoresist (4); after removal, clean and dry the metal substrate; Step 8, deposit a third insulating layer (601) on the surface of the bonding layer above the second electrode sensing layer (502) by electron beam evaporation process; deposit a fourth insulating layer (602) on the third insulating layer (601) by atomic layer deposition process; Step 9, deposit a bonding layer and a conductive seed layer (8) on the surface of the fourth insulating layer (602) in sequence by magnetron sputtering process; Step 10, deposit a protective layer (9) on the conductive seed layer (8) by electroplating process, thereby forming a sandwiched layered packaging structure; Step 11, remove the insulating layer on the surface of the sensor pad (10) by plasma etching process; Step 12, connect the lead wire (11) to the sensor pad (10), and bake it using a hot plate; after baking and curing, apply a layer of epoxy resin on the sensor pad (10) and cure it for t hours, thereby forming a micro-nano film temperature sensor.

6. The method of claim 5, wherein, The time range of t is 10 hours to 36 hours.

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