A high-temperature thin-film heat flow-temperature integrated sensor and a preparation method thereof
By combining Al2O3 ceramic tubes with ceramic substrates and Au-Pt-Ni multilayer metallization design, and combining magnetron sputtering and PECVD technology, a high-temperature thin-film heat flow-temperature integrated sensor was fabricated, which solved the problems of sensor stability and measurement accuracy under high temperature environment, and realized the long-term service and accurate measurement of the sensor under high temperature.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ZHONGBEI UNIV
- Filing Date
- 2026-03-16
- Publication Date
- 2026-05-29
Smart Images
Figure CN122108400A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of heat flow and temperature measurement technology, specifically to a high-temperature thin-film integrated heat flow-temperature sensor and its fabrication method. Background Technology
[0002] Heat flux density is a core parameter characterizing energy transfer properties in high-temperature extreme environments, and its accurate measurement is directly related to technological breakthroughs and safety assurance in key fields such as aerospace, energy and power, and high-end manufacturing. In high-temperature scenarios such as aero-engine combustors, spacecraft reentry thermal protection systems, aero-engine combustor and exhaust nozzle heat flux and temperature monitoring, high-temperature pipelines, reactor wall heat flux combined with temperature synchronous monitoring, and nuclear reactor cores, heat flux density distribution is uneven, and instantaneous fluctuations are severe. Furthermore, it is accompanied by complex operating conditions such as high-temperature oxidation, thermal shock, and vibration, placing stringent requirements on heat flux measurement technology for "high temperature resistance, fast response, high precision, and anti-interference." Real-time and accurate measurement of heat flux and temperature on the surface of critical components is crucial for evaluating performance and lifespan. Existing integrated sensors mostly employ metal thermopile or low-temperature oxide materials, which suffer from drawbacks such as poor high-temperature stability, low thermoelectric potential output, and weak adhesion to ceramic substrates. Furthermore, the sensor's cold-end heat dissipation efficiency is unstable, leading to large temperature fluctuations and low measurement accuracy. In addition, the fabrication process suffers from problems such as low patterning accuracy, poor film compatibility, and unreliable bonding between ceramic and metal heat sinks, limiting their long-term service life under high-temperature conditions. Therefore, there is an urgent need to develop a compact, high-temperature stable, accurate, and feasible integrated heat flow-temperature sensor to address the shortcomings of existing technologies. Summary of the Invention
[0003] To address the shortcomings of existing technologies, this invention provides a high-temperature thin-film heat flow-temperature integrated sensor, comprising: (Al2O3)0.7(YSZ)0.3 composite film, thin-film heat flow sensor, thin-film temperature sensor, and sensor base; The thin-film heat flow sensor includes an Al2O3 thermal resistance layer film and an ITO / In2O3 functional film. The thin-film temperature sensor includes a PT1000 functional thin film; The sensor base includes a ceramic element with a through hole. An Al2O3 ceramic tube is placed inside the hole. The end face of the Al2O3 ceramic tube is flush with the surface of the sensor base. The mating surface is coated with high-temperature brazing filler metal and metallurgically bonded by brazing. The inside of the Al2O3 ceramic tube is filled with a Ni core, and the tube wall of the Al2O3 ceramic tube is Au-Pt-Ni multilayer metallized. The ITO / In2O3 functional film and the Al2O3 thermal resistance layer film are sequentially disposed on the upper surface of the sensor base from bottom to top; the PT1000 functional film is disposed in the center of the sensor base. The ITO / In2O3 functional thin film adopts a circular petal-shaped symmetrical structure, including circumferentially distributed arc-shaped folded arms to form a thermopile sensitive layer.
[0004] Furthermore, the circular petal-shaped symmetrical structure of the ITO / In2O3 functional film includes: a circular outline without sharp corners; a single-lobed arc-shaped folded arm; and uniform gaps.
[0005] Furthermore, the Au-Pt-Ni multilayer metallization structure includes: The bottom Ni metal layer, with a thickness of 50~200nm, serves as an adhesion transition layer; The intermediate Pt metal layer, with a thickness of 100~300nm, serves as a high-temperature diffusion barrier and an anti-oxidation barrier. The surface Au metal layer, with a thickness of 200~500nm, serves as a low-resistance conductive layer, an anti-oxidation surface layer, and a lead bonding layer.
[0006] Furthermore, the thermopile sensitive layer composed of the ITO / In2O3 functional thin film is prepared by magnetron sputtering at a deposition temperature of 100℃, a working pressure of 0.3-0.8 Pa, and a power density of 2-4 W / cm³. 2 .
[0007] Furthermore, a Ti adhesion layer with a thickness of 10~20nm is provided between the PT1000 functional thin film and the ceramic element.
[0008] Furthermore, a (Al2O3)0.7(YSZ)0.3 composite film is coated on the surface of the sensor, comprising: Bottom layer (Al2O3) 0.7 (YSZ) 0.3 The membrane, acting as a transition layer, enhances the adhesion between the composite membrane and the functional layers of the substrate; the upper layer (Al2O3) 0.7 (YSZ) 0.3 Membranes, as protective layers, are used to improve the density and environmental protection performance of membranes.
[0009] Furthermore, the upper surface of the ceramic element and the end face of the Al2O3 ceramic tube are polished to the same plane, with a surface roughness Ra≤0.15μm.
[0010] Furthermore, the thickness of the Al2O3 thermal resistance layer film is 500nm~2μm; the thickness of the ITO / In2O3 functional film is 200~600nm; and the thickness of the PT1000 functional film is 100~300nm.
[0011] This invention also proposes a method for fabricating a high-temperature thin-film heat flow-temperature integrated sensor, comprising the following steps: S1: The ceramic substrate and Al2O3 ceramic tube are joined at the end face, and high-temperature brazing filler metal is applied around the joint surface to achieve metallurgical bonding through brazing; Ni core is filled inside the tube, and Au-Pt-Ni multilayer metallization is performed on the outer wall of the ceramic tube to form PT1000 compensation end and ITO / In2O3 compensation end. S2: Place the ceramic substrate obtained in step S1 into a magnetron sputtering apparatus, and set the deposition temperature to 100℃, the working pressure to 0.3~0.8Pa, and the power density to 2~4W / cm³. 2 Under the process conditions, a thermopile sensitive layer is deposited using a mask sputtering method; S3: First, a Ti adhesion layer is sputtered using a mask sputtering method. Then, a PT1000 thin film layer is sputtered using a high-purity Pt target under conditions of room temperature 150℃, pure Ar atmosphere, and pressure of 0.3~0.6Pa. S4: An Al2O3 thermal resistance layer was deposited on the cold node surface of the prepared thermopile sensitive layer using an ICPCVD system at a deposition temperature of 80~150℃ and a film thickness of 500nm~2μm. S5: Al2O3 is deposited on the entire surface of the sensor substrate using a PECVD system. 0.7 (YSZ) 0.3 The composite membrane is a double-layer membrane with a deposition temperature of 150~250℃ and a thickness of 500~1000nm. It adopts the same system and core process parameters, step-by-step deposition, and no pressure relief in the middle of the cavity during the deposition process.
[0012] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention utilizes magnetron sputtering, ICP-CVD, and PECVD thin film fabrication technologies, combining the advantages of small size and fast response speed, to achieve precise simultaneous measurement of transient temperature and heat flux density. A ceramic substrate paired with an Al2O3 ceramic tube is selected, possessing high-temperature resistance and forming good thermal and structural matching with the oxide film layer. Through an Au-Pt-Ni multilayer metallization design, a composite structure with high-temperature diffusion barrier, oxidation resistance, and low-resistance conductivity is constructed, ensuring interfacial bonding strength, hermeticity, and conductivity stability at high temperatures. The Ti adhesion layer effectively prevents PT10. The thin film layer peels off, improving the film layer adhesion; the double-layer film design of Al2O3 thermal resistance layer film and (Al2O3)0.7(YSZ)0.3 composite film has low thermal conductivity, high insulation and environmental stability, which not only improves the sensitivity of heat flux density measurement, but also effectively protects the functional layers of the substrate and inhibits oxidation and interface diffusion; the sensor of this invention can adapt to high temperature and complex working conditions, without the need for additional signal amplification and processing, and realizes synchronous and long-term stable measurement of temperature and heat flux density. The structure is compact, and the structural stability and measurement accuracy at high temperature are significantly improved. Attached Figure Description
[0013] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.
[0014] Figure 1 This is a diagram showing the assembly and stacking sequence of the high-temperature thin-film heat flow-temperature integrated sensor of the present invention in an embodiment; Figure 2 This is a front view of the assembled stack of the high-temperature thin-film heat flow-temperature integrated sensor of the present invention in an embodiment; Figure 3 This is a front view of the actual stacked assembly of the high-temperature thin-film heat flow-temperature integrated sensor of the present invention in an embodiment; Figure 4 This is a top view of the thin-film thermopile structure of the high-temperature thin-film heat flow-temperature integrated sensor of the present invention in an embodiment; Figure 5 This is a top view of the thin-film PT1000 structure of the high-temperature thin-film heat flow-temperature integrated sensor of the present invention in an embodiment; Figure 6 This is a top view of the thermal resistance layer and functional thin film structure of the high-temperature thin film heat flow-temperature integrated sensor of the present invention in an embodiment; In the figure: 1. Top layer (Al2O3)0.7(YSZ)0.3 film; 2. Bottom layer (Al2O3)0.7(YSZ)0.3 film; 3. ITO / In2O3 functional film; 4. Al2O3 thermal resistance layer film; 5. PT1000 film; 6. Ceramic element; 7. PT1000 compensation end; 8. ITO / In2O3 compensation end. Detailed Implementation
[0015] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.
[0016] Example 1 like Figure 1-3 As shown, this invention provides a high-temperature thin-film heat flow-temperature integrated sensor, comprising: a (Al2O3)0.7(YSZ)0.3 composite film, a thin-film heat flow sensor, a thin-film temperature sensor, and a sensor base, wherein: Thin-film heat flow sensor, including Al2O3 thermal resistance layer film 4 and ITO / In2O3 functional film 3; Thin-film temperature sensors include PT1000 functional thin-film sensors; Among them, the ITO / In2O3 functional film 3 and the Al2O3 thermal resistance layer film 4 are sequentially arranged on the upper surface of the sensor base from bottom to top; the PT1000 functional film 5 is located in the center of the sensor base.
[0017] The ITO / In2O3 functional thin film adopts a circular petal-shaped symmetrical structure and uniformly distributed folded arms around the circumference, enabling omnidirectional heat flow reception. The single-lobed arc-shaped folded design replaces the traditional straight folded design, reducing corner losses during heat flow conduction. The circular outline has no sharp corners, further reducing heat flow loss at the structural edges. Combined with the uniform gap design, it can accurately capture heat flow signals and improve sensor detection accuracy. The structure is more stable and has a longer service life. The overall symmetrical structure has no stress concentration points, and the arc-shaped folded arms and smooth arc transition design significantly improve the flexibility of the sensitive unit (ITO / In2O3 functional thin film) and reduce the risk of film cracking and peeling. At the same time, the uniform gap design facilitates uniform coverage of the PECVD composite protective layer without any coverage blind spots.
[0018] The sensor base includes a ceramic element 6 with four through holes. An Al2O3 ceramic tube is placed inside the holes. The end face of the ceramic tube is flush with the surface of the substrate. The mating surface is coated with high-temperature brazing filler metal and metallurgically bonded by brazing to achieve a stable bond at high temperature. The tube is filled with a Ni core and the tube wall is multi-layered metallized with Au-Pt-Ni to form a PT1000 compensation end 7 and an ITO / In2O3 compensation end 8. The ceramic element 6 and its upper surface are polished together to the same plane with a surface roughness Ra≤0.15μm to ensure the coating quality.
[0019] Example 2 This embodiment proposes a method for fabricating a thin-film heat flow-temperature sensor based on the above, including the following steps: The first step involves placing an Al2O3 ceramic tube within the substrate and its cavity, with the tube end flush with the substrate surface. A high-temperature brazing filler metal is applied around the joint, and metallurgical bonding is achieved through brazing. This ensures interfacial bonding strength, airtightness, and long-term structural stability under high-temperature conditions. The tube is then filled with a Ni core, and the outer wall of the ceramic tube undergoes Au-Pt-Ni multilayer metallization: first, a Ni metal layer with a thickness of 50-200 nm is deposited on the ceramic surface at room temperature using DC magnetron sputtering; then, a Pt metal layer with a thickness of 100-300 nm is sputtered on top of the Ni layer. This serves as a diffusion barrier and oxidation resistance layer at high temperatures, preventing the underlying Ni from diffusing outwards and avoiding failure of the precious metal layer. Simultaneously, it enhances high-temperature structural stability and acts as an adhesion transition layer between the ceramic and precious metal layers, suppressing interfacial diffusion and improving bonding strength. Finally, an Au metal layer with a thickness of 200~500nm is deposited as a low-resistance conductive layer, an anti-oxidation surface layer, and a lead bonding layer to ensure stable conductivity and brazing bonding at high temperatures, reduce contact resistance, and form the PT1000 compensation terminal 7 and the ITO / In2O3 compensation terminal 8.
[0020] The second step involves placing the ceramic substrate, which has undergone the first step of processing, into a magnetron sputtering apparatus. Under the process conditions of a deposition temperature of 100℃, a working pressure of 0.3~0.8Pa, and a power density of 2~4W / cm², a thin film is deposited on the substrate surface using a magnetron sputtering method. The thin film is then patterned using a mask sputtering method to form a thermopile sensitive layer on the substrate surface. The thickness of the thin film is 200–600nm.
[0021] The third step, in order to prevent the PT1000 thin film layer from peeling, firstly, a Ti adhesion layer with a thickness of 10~20nm is sputtered using a mask sputtering method. Then, a PT1000 thin film layer with a thickness of 100~300nm is sputtered using a high-purity Pt target (99.99%) at room temperature~150℃ and a pure Ar atmosphere with a gas pressure of 0.3~0.6Pa.
[0022] The fourth step involves depositing an Al2O3 thermal resistance layer on the cold node surface of the prepared thermopile sensitive layer using an ICPCVD system at a deposition temperature of 80~150℃. The film thickness is 500nm~2μm deposited under low pressure.
[0023] Step 5: A (Al2O3)0.7(YSZ)0.3 composite film is deposited on the overall surface of the sensor substrate using a PECVD system. The (Al2O3)0.7(YSZ)0.3 composite film is a bilayer film, with a deposition temperature of 150~250℃ and a thickness of 500~1000nm. The bilayer film deposition adopts the same system and core process parameters, step-by-step deposition, and no pressure relief in the middle of the cavity during the deposition process. The bottom layer (Al2O3)0.7(YSZ)0.3 film in the bilayer film is deposited as a transition layer to improve the bonding force between the composite protective layer and the functional layers of the substrate. The top layer (Al2O3)0.7(YSZ)0.3 film in the bilayer film is a protective layer to improve the film density and environmental protection performance. Finally, it fully covers all functional layers of the sensor substrate, forming a composite film structure with low thermal conductivity, high insulation and environmental stability.
[0024] This invention utilizes thin film preparation technologies such as magnetron sputtering, ICP-CVD, and PECVD, combining the advantages of small size and fast response speed to achieve precise measurement of transient temperature and heat flux density. A ceramic substrate paired with an Al2O3 ceramic tube is selected, possessing high-temperature resistance and forming good thermal and structural matching with the oxide film layer. Through an Au-Pt-Ni multilayer metallization design, a composite structure with high-temperature diffusion barrier, oxidation resistance, and low-resistance conductivity is constructed, ensuring interfacial bonding strength, airtightness, and conductivity stability at high temperatures. The Ti adhesion layer effectively prevents PT1000 film layer peeling and improves film adhesion. The dual-layer design of the Al2O3 thermal resistance layer film and the (Al2O3)0.7(YSZ)0.3 composite film combines low thermal conductivity, high insulation, and environmental stability. This not only improves the sensitivity of heat flux density measurement but also effectively protects the functional layers of the substrate, inhibiting oxidation and interfacial diffusion. The sensor of this invention can adapt to high-temperature and complex working conditions without additional signal amplification and processing, achieving synchronous and long-term stable measurement of temperature and heat flux density. The compact structural design significantly improves structural stability and measurement accuracy at high temperatures.
[0025] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A high-temperature thin-film heat flow-temperature integrated sensor, characterized in that, include: (Al2O3)0.7(YSZ)0.3 composite film, thin film heat flow sensor, thin film temperature sensor and sensor base; The thin-film heat flow sensor includes an Al2O3 thermal resistance layer film and an ITO / In2O3 functional film. The thin-film temperature sensor includes a PT1000 functional thin film; The sensor base includes a ceramic element with a through hole. An Al2O3 ceramic tube is placed inside the hole. The end face of the Al2O3 ceramic tube is flush with the surface of the sensor base. The mating surface is coated with high-temperature brazing filler metal and metallurgically bonded by brazing. The inside of the Al2O3 ceramic tube is filled with a Ni core, and the tube wall of the Al2O3 ceramic tube is Au-Pt-Ni multilayer metallized. The ITO / In2O3 functional film and the Al2O3 thermal resistance layer film are sequentially disposed on the upper surface of the sensor base from bottom to top; the PT1000 functional film is disposed in the center of the sensor base. The ITO / In2O3 functional thin film adopts a circular petal-shaped symmetrical structure, including circumferentially distributed arc-shaped folded arms to form a thermopile sensitive layer.
2. The high-temperature thin-film heat flow-temperature integrated sensor according to claim 1, characterized in that, The circular petal-shaped symmetrical structure of the ITO / In2O3 functional thin film includes: a circular outline without sharp corners; a single-lobed arc-shaped folded arm; and uniform gaps.
3. The high-temperature thin-film heat flow-temperature integrated sensor according to claim 1, characterized in that, The Au-Pt-Ni multilayer metallization structure includes: The bottom Ni metal layer, with a thickness of 50~200nm, serves as an adhesion transition layer; The intermediate Pt metal layer, with a thickness of 100~300nm, serves as a high-temperature diffusion barrier and an anti-oxidation barrier. The surface Au metal layer, with a thickness of 200~500nm, serves as a low-resistance conductive layer, an anti-oxidation surface layer, and a lead bonding layer.
4. The high-temperature thin-film heat flow-temperature integrated sensor according to claim 1, characterized in that, The thermopile sensitive layer composed of the ITO / In2O3 functional thin film was prepared by magnetron sputtering at a deposition temperature of 100℃, a working pressure of 0.3-0.8 Pa, and a power density of 2-4 W / cm³. 2 .
5. The high-temperature thin-film heat flow-temperature integrated sensor according to claim 1, characterized in that, A Ti adhesion layer with a thickness of 10~20nm is also provided between the PT1000 functional thin film and the ceramic element.
6. The high-temperature thin-film heat flow-temperature integrated sensor according to claim 1, characterized in that, A (Al2O3)0.7(YSZ)0.3 composite film covers the surface of the sensor, comprising: Bottom layer (Al2O3) 0.7 (YSZ) 0.3 The membrane, as a transition layer, is used to enhance the bonding force between the composite membrane and the functional layers of the substrate; the upper (Al2O3)0.7(YSZ)0.3 membrane, as a protective layer, is used to enhance the membrane density and environmental protection performance.
7. The high-temperature thin-film heat flow-temperature integrated sensor according to claim 1, characterized in that, The upper surface of the ceramic element and the end face of the Al2O3 ceramic tube are polished to the same plane, with a surface roughness Ra≤0.15μm.
8. The high-temperature thin-film heat flow-temperature integrated sensor according to claim 1, characterized in that, The thickness of the Al2O3 thermal resistance layer film is 500nm~2μm; the thickness of the ITO / In2O3 functional film is 200~600nm; and the thickness of the PT1000 functional film is 100~300nm.
9. A method for fabricating a high-temperature thin-film heat flow-temperature integrated sensor as described in any one of claims 1-8, characterized in that, Includes the following steps: S1: The ceramic substrate and Al2O3 ceramic tube are joined at the end face, and high-temperature brazing filler metal is applied around the joint surface to achieve metallurgical bonding through brazing; Ni core is filled inside the tube, and Au-Pt-Ni multilayer metallization is performed on the outer wall of the ceramic tube to form PT1000 compensation end and ITO / In2O3 compensation end. S2: Place the ceramic substrate obtained in step S1 into a magnetron sputtering apparatus, and set the deposition temperature to 100℃, the working pressure to 0.3~0.8Pa, and the power density to 2~4W / cm³. 2 Under the process conditions, a thermopile sensitive layer is deposited using a mask sputtering method; S3: First, a Ti adhesion layer is sputtered using a mask sputtering method. Then, a PT1000 thin film layer is sputtered using a high-purity Pt target under conditions of room temperature 150℃, pure Ar atmosphere, and pressure of 0.3~0.6Pa. S4: An Al2O3 thermal resistance layer was deposited on the cold node surface of the prepared thermopile sensitive layer using an ICPCVD system at a deposition temperature of 80~150℃ and a film thickness of 500nm~2μm. S5: Al2O3 is deposited on the entire surface of the sensor substrate using a PECVD system. 0.7 (YSZ) 0.3 The composite membrane is a double-layer membrane with a deposition temperature of 150~250℃ and a thickness of 500~1000nm. It adopts the same system and core process parameters, step-by-step deposition, and no pressure relief in the middle of the cavity during the deposition process.