WO2024067123A1 - High-sensitivity thermal micro-flow sensor based on phase change material - Google Patents
High-sensitivity thermal micro-flow sensor based on phase change material Download PDFInfo
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- WO2024067123A1 WO2024067123A1 PCT/CN2023/118785 CN2023118785W WO2024067123A1 WO 2024067123 A1 WO2024067123 A1 WO 2024067123A1 CN 2023118785 W CN2023118785 W CN 2023118785W WO 2024067123 A1 WO2024067123 A1 WO 2024067123A1
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- phase change
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- single crystal
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- 239000012782 phase change material Substances 0.000 title claims abstract description 32
- 238000010438 heat treatment Methods 0.000 claims abstract description 37
- 239000012530 fluid Substances 0.000 claims abstract description 28
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 24
- 239000000463 material Substances 0.000 claims abstract description 24
- 239000000758 substrate Substances 0.000 claims abstract description 16
- 238000001514 detection method Methods 0.000 claims abstract description 15
- 238000011144 upstream manufacturing Methods 0.000 claims abstract description 15
- 239000013078 crystal Substances 0.000 claims abstract description 14
- 239000000377 silicon dioxide Substances 0.000 claims abstract description 12
- 235000012239 silicon dioxide Nutrition 0.000 claims abstract description 12
- 238000002955 isolation Methods 0.000 claims abstract description 8
- 229910021421 monocrystalline silicon Inorganic materials 0.000 claims abstract description 5
- 239000002210 silicon-based material Substances 0.000 claims abstract description 4
- 230000035772 mutation Effects 0.000 claims description 12
- 229910052751 metal Inorganic materials 0.000 claims description 10
- 239000002184 metal Substances 0.000 claims description 10
- 238000000034 method Methods 0.000 claims description 9
- 230000008859 change Effects 0.000 claims description 8
- 238000004806 packaging method and process Methods 0.000 claims description 6
- 230000008569 process Effects 0.000 claims description 5
- 239000004205 dimethyl polysiloxane Substances 0.000 claims description 3
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical group [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims description 3
- 239000010931 gold Substances 0.000 claims description 3
- 229910052737 gold Inorganic materials 0.000 claims description 3
- 238000009413 insulation Methods 0.000 claims description 3
- 229920000435 poly(dimethylsiloxane) Polymers 0.000 claims description 3
- -1 polydimethylsiloxane Polymers 0.000 claims description 3
- 229910044991 metal oxide Inorganic materials 0.000 claims description 2
- 150000004706 metal oxides Chemical class 0.000 claims description 2
- 230000035945 sensitivity Effects 0.000 abstract description 13
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 7
- GRUMUEUJTSXQOI-UHFFFAOYSA-N vanadium dioxide Chemical compound O=[V]=O GRUMUEUJTSXQOI-UHFFFAOYSA-N 0.000 description 7
- 230000009977 dual effect Effects 0.000 description 6
- 238000004088 simulation Methods 0.000 description 6
- 230000006872 improvement Effects 0.000 description 5
- 101100012902 Saccharomyces cerevisiae (strain ATCC 204508 / S288c) FIG2 gene Proteins 0.000 description 4
- 229910021542 Vanadium(IV) oxide Inorganic materials 0.000 description 4
- 238000004458 analytical method Methods 0.000 description 4
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- 239000003814 drug Substances 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 229910052697 platinum Inorganic materials 0.000 description 3
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
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- 229910052710 silicon Inorganic materials 0.000 description 2
- 239000010703 silicon Substances 0.000 description 2
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- 230000007704 transition Effects 0.000 description 2
- 229910001218 Gallium arsenide Inorganic materials 0.000 description 1
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- 102100026388 L-amino-acid oxidase Human genes 0.000 description 1
- 102100023591 Polyphosphoinositide phosphatase Human genes 0.000 description 1
- 101100233916 Saccharomyces cerevisiae (strain ATCC 204508 / S288c) KAR5 gene Proteins 0.000 description 1
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
- G01F1/68—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using thermal effects
- G01F1/684—Structural arrangements; Mounting of elements, e.g. in relation to fluid flow
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
- G01F1/68—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using thermal effects
- G01F1/684—Structural arrangements; Mounting of elements, e.g. in relation to fluid flow
- G01F1/6847—Structural arrangements; Mounting of elements, e.g. in relation to fluid flow where sensing or heating elements are not disturbing the fluid flow, e.g. elements mounted outside the flow duct
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
- G01F1/68—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using thermal effects
- G01F1/684—Structural arrangements; Mounting of elements, e.g. in relation to fluid flow
- G01F1/688—Structural arrangements; Mounting of elements, e.g. in relation to fluid flow using a particular type of heating, cooling or sensing element
- G01F1/69—Structural arrangements; Mounting of elements, e.g. in relation to fluid flow using a particular type of heating, cooling or sensing element of resistive type
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F15/00—Details of, or accessories for, apparatus of groups G01F1/00 - G01F13/00 insofar as such details or appliances are not adapted to particular types of such apparatus
- G01F15/18—Supports or connecting means for meters
Definitions
- the invention relates to fluid metering equipment, in particular to a high-sensitivity thermal micro-flow sensor based on phase change material.
- Micro flow sensors are an important component of microfluidic systems. They monitor the flow state of microfluids and provide information on the flow of fluids in microchannels, thereby achieving precise control of microfluidics in micro-total analysis systems. They are of great significance to the scientific research and engineering applications of microfluidic systems.
- MEMS microflow sensors made based on silicon-based micromachining technology have the advantages of miniaturization, low power consumption and high performance, and are widely used in aerospace, clinical medicine, biopharmaceuticals and fine chemicals.
- the methods and detection devices for measuring microfluidic flow have the disadvantages of being easily interfered by external factors, large measurement errors and discontinuity.
- the miniaturization process of the analysis system and the further research and development of emerging chip laboratory technologies such as flow cytometry, particle sorting, and flow mixing have also put forward higher and higher measurement requirements for the performance of microflow sensors.
- MEMS micro flow sensors can be roughly divided into three categories according to their sensing principles: piezoresistive, piezoelectric, and thermal.
- Piezoresistive sensors show excellent performance in low flow detection, but they are easily affected by temperature and humidity, which limits their application in biomedicine; piezoelectric sensors are often used for oscillating flow detection and have the advantage of self-power supply, but the high internal resistance of piezoelectric materials makes them unsuitable for static flow detection.
- Thermal sensors can realize multiplexed detection of gases and liquids and have potential application value in high-sensitivity micro-flow detection.
- Thermal micro-flow sensors usually consist of a heating resistor and a thermistor.
- the implementation methods mainly include three configuration schemes: heat loss, heat distribution, and heat pulse.
- the optimization of the sensitivity, power consumption and other performance of this type of sensor mainly depends on how to increase the convective heat transfer in the ambient fluid and maximize the temperature change under forced convection. It requires comprehensive consideration from the selection of thermistor sensitive materials and sensor geometric structure design.
- thermal micro-flow sensors are mostly limited to the improvement of the insulation substrate structure and the integration of different configuration schemes, lacking breakthroughs in the temperature coefficient of resistance of the core thermal sensitive material.
- performance improvement of thermal micro-flow sensors is restricted, which seriously hinders the rapid development of microfluidic technology.
- the inventors found that the existing research results of micro-flow sensors have the above-mentioned problems. Therefore, they hope to have a high-sensitivity thermal micro-flow sensor based on phase change material that can solve the problem of low detection sensitivity of existing MEMS thermal flow sensors under small flow rates.
- the purpose of the present invention is to provide a high-sensitivity thermal micro-flow sensor based on phase change material, comprising a single crystal substrate, a fluid layer and two groups of fixed beams provided with sensing units;
- a heat-insulating dielectric film is deposited on the upper surface of the single crystal substrate; a fluid layer is arranged above the heat-insulating dielectric film; a microchannel for fluid circulation is constructed between the heat-insulating dielectric film and the fluid layer; the two groups of clamped beams are respectively suspended upstream and downstream of the microchannel; the clamped beams include a silicon dioxide isolation layer for supporting the entire clamped beam, a sensor unit arranged on the upper surface of the silicon dioxide isolation layer of the clamped beam, and a packaging layer for packaging the sensor unit;
- the sensing unit includes a heating resistor for heating the fluid temperature, a thermistor capable of generating different voltage signals according to the temperature difference, and a metal wire for connecting the circuit; the heating resistor is connected to an external power supply circuit; the material of the thermistor is a first-order phase change material based on temperature-induced resistivity mutation, the thermistor is arranged on the metal wire, and is connected to the external detection circuit through the metal wire; there is a gap between the thermistor and the heating resistor.
- the heating resistor generates heat after power is supplied.
- the fluid flow in the microchannel will cause a difference in the temperature measured by the thermistors on both sides; this difference causes a difference in the resistance values of the thermistors on both sides, and the external detection circuit will detect two different voltage signals, which are subtracted from each other and used as the final output voltage signal.
- these first-order phase change materials based on temperature-induced resistivity mutation are metal oxides and their doping materials having resistivity mutation characteristics during phase change. More preferably, the first-order phase change materials based on temperature-induced resistivity mutation are vanadium dioxide, V 0.95-x Cr x Nb 0.05 O 2 , VO 2 /GaAs heterojunction, etc.
- the heat insulating medium film is a silicon dioxide isolation layer.
- the upper fluid layer is constructed of polydimethylsiloxane.
- the two groups of clamped beams are mirror-mounted on the microfluidic channel, and the fluid flows from the upstream to the downstream of the microfluidic channel and passes through the thermistor of the upstream clamped beam, the heating resistor of the upstream clamped beam, the heating resistor of the downstream clamped beam, and the thermistor of the downstream clamped beam in sequence.
- the heating resistor is made of gold.
- the upstream heating resistor and the downstream heating resistor can be independently controlled by external power supply circuits respectively.
- the length of the clamping beam is greater than the width of the flow channel, and the single crystal substrates on both sides of the flow channel are connected.
- the single crystal substrate is made of single crystal silicon material.
- the beneficial effect of the present invention is that the present invention selects a first-order phase change material based on temperature-induced resistivity mutation as the material of the thermistor, and utilizes its ultra-high TCR characteristics in the thermal phase change range to achieve a significant improvement in the sensitivity of the thermistor, breaking through the application of nonlinear metamaterials in thermal micro-flow sensors; further, through the dual heating resistor configuration, the sensing units on the upstream and downstream fixed-support beams can independently control their respective first-order phase change material thermistors based on temperature-induced resistivity mutation to be at the optimal operating temperature, while ensuring that the resistance change of the thermistor follows the monotonous change of the main loop of the cooling curve and heating curve of the first-order phase change material based on the temperature-induced resistivity mutation, thereby avoiding the influence of hysteresis.
- Fig. 1 is a schematic structural diagram of the present invention
- Fig. 2 is a top view of the structural principle of the present invention.
- FIG3 is a cross-sectional view taken along line A1-A1 of FIG2 ;
- FIG4 is a cross-sectional view taken along line A2-A2 of FIG2 ;
- FIG5 is a cross-sectional view taken along line B1-B1 of FIG2 ;
- FIG6 is a cross-sectional view taken along line B2-B2 of FIG2 ;
- FIG7 is a diagram showing simulation results of flow sensors with two configurations (heat loss and dual heater configuration of the present invention) in which the sensitive material is vanadium dioxide;
- FIG8 is a diagram showing simulation results of flow sensors with three configurations (heat loss, heat distribution, and the dual-heater configuration of the present invention) whose sensitive material is platinum.
- thermoistor 2. metal connection; 3. packaging layer; 4. heating resistor; 5. fluid layer; 6. thermal insulation dielectric film; 7. single crystal substrate.
- the present invention proposes a highly sensitive thermal micro flow sensor based on phase change material, which is further described below in conjunction with the accompanying drawings and embodiments.
- the resistivity mutation characteristic of the phase change process, the high-sensitivity thermal micro-flow sensor based on phase change material provided in the embodiment of the present invention can be applicable to the extremely low flow range of microliters or nanoliters, and can be applied to chemical analysis, clinical medicine, biopharmaceuticals and precision manufacturing and other fields.
- a highly sensitive thermal micro-flow sensor based on phase change material comprises a single crystal substrate 7 whose lower layer is single crystal silicon material, a fluid layer 5 made of polydimethylsiloxane material and two groups of fixed beams provided with sensing units on the upper layer of the microchannel; as shown in FIGS.
- the fixed beam is mounted on the microchannel opened between the single crystal substrate 7 and the fluid layer 5 and the length of the fixed beam is greater than the width of the channel, connecting the single crystal substrates on both sides of the channel, and the two groups of fixed beams are suspended and respectively mounted upstream and downstream of the microchannel;
- the lower layer of the fixed beam is a heat-insulating dielectric film made of silicon dioxide, which plays a role in supporting the fixed beam as a whole;
- the heating resistor and the metal connection are both arranged on the upper surface of the heat-insulating dielectric film of the fixed beam;
- the thermistor is arranged on the metal connection line, and the upper layer is a packaging layer made of silicon dioxide.
- the material of the thermistor is a first-order phase change material based on temperature-induced resistivity mutation, and vanadium dioxide is selected in this embodiment;
- the phase transition temperature of vanadium dioxide is 68°C, and it has the advantages of high response rate, high resistance temperature coefficient and good MEMS process compatibility, etc. It has a TCR of up to -27000ppm/K at room temperature, and the TCR in the IMT range can reach up to about -700000ppm/K.
- VO2 has great potential application value in high-sensitivity heat flow detection.
- the resistivity of the thermistor changes by three orders of magnitude in the reversible thermoinduced phase transition range.
- the length is 16 ⁇ m
- the width is 16 ⁇ m
- a heating resistor and a thermistor are arranged on the silicon dioxide isolation layer, as shown in Figure 2.
- the fixed support beam is mirrored, they are arranged in the flow channel in the order of thermistor, heating resistor, heating resistor, and thermistor in the downstream direction.
- the two heating resistors are powered by an external circuit, and the heating resistors generate heat after power supply.
- the flow of fluid in the microchannel causes a difference in the fluid temperature measured by the thermistors on both sides; this difference causes a difference in the resistance value of the thermistors on both sides, and the external detection circuit will detect two different voltage signals.
- the two voltage signals are then subtracted from each other as the final output voltage signal, and the final output voltage signal is then converted into the corresponding fluid flow rate, thereby realizing the thermal micro-flow measurement principle.
- the commercial simulation software COMSOL Multiphysics 5.6 was used to simulate and calculate the output voltage signal of the sensor with a microfluid (air) flow rate range of 0 to 1 ⁇ L ⁇ min -1 in Example 1 of the present invention, and compared with the output voltage of sensors with the same thermistor material and different configurations. The results are shown in FIG7 .
- the commercial simulation software COMSOL Multiphysics 5.6 was used to simulate the sensor output voltage signal in the microfluid (air) flow range of 0 to 1 ⁇ L ⁇ min -1 in Example 1 of the present invention.
- the other simulation conditions were kept the same, the material of the thermistor was changed to platinum, and the output voltage signals of the flow sensors of the three configurations were compared. The results are shown in FIG8 .
- the high-sensitivity thermal micro-flow sensor based on phase change material in which two heating resistors are independently controlled by an external power supply circuit (dual heater type) proposed by the present invention has a linear response within the flow range of 0 to 0.2 ⁇ L ⁇ min -1 , and a sensitivity of up to 1.34V/( ⁇ L ⁇ min -1 ), which is about 80.50 times the sensitivity of the heat loss flow sensor of 16.69mV/( ⁇ L ⁇ min -1 ).
- the sensitivity is saturated within a higher flow range, but the sensitivity can still reach 35.04mV/( ⁇ L ⁇ min -1 ), indicating that the configuration of two heating resistors independently controlled by an external power supply circuit (dual heater type) can significantly improve the sensitivity of the sensor, and has potential application prospects at extremely low flow rates.
- the flow sensor based on the configuration in which the two heating resistors are independently controlled by the external power supply circuit (dual heater type) of the present invention has higher detection sensitivity, which also illustrates the universality of the sensitive materials selected by the present invention in different configurations; combined with Figures 7 and 8, it can be seen that under the same configuration, compared with the Pt-based flow sensor, the VO2 -based flow sensor has a significant improvement in the sensitivity of detecting extremely low fluid flow rates, indicating that the ultra-high TCR characteristics of the VO2 thermal phase change range can achieve a significant improvement in sensor sensitivity, and theoretically demonstrates the feasibility of using nonlinear metamaterials in high-sensitivity thermal micro-flow sensors.
- the high-sensitivity thermal micro-flow sensor based on phase change material designed by the present invention selects nonlinear phase change material as the sensitive material and combines it with a dual heater structure to achieve independent temperature control, avoid the influence of hysteresis, and greatly improve the sensitivity of the sensor. It has a small size and high resolution, and can be used in an extremely low flow range of microliters or nanoliters. It can be used in chemical analysis, clinical medicine, biopharmaceuticals, precision manufacturing and other fields.
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Abstract
A high-sensitivity thermal micro-flow sensor based on a phase change material, comprising a single crystal substrate (7), a fluid layer (5), and two fixed support beams provided with sensing units. The single crystal substrate (7) is made of a single crystal silicon material, a dense thermal insulating dielectric film (6) is deposited on the single crystal silicon substrate, and the two fixed support beams are respectively suspended upstream and downstream of a micro-flow channel; and the sensing units consisting of heating resistors (4) and thermistors (1) are located on the upper surfaces of silicon dioxide isolation layers of the fixed support beams. By improving the sensitive material and using phase change material layers having a high absolute value of temperature coefficient of resistance as thermistors, the detection sensitivity of the sensor is improved, and the two heating resistors (4) are independently controlled by an external power supply circuit, so that independent control of respective temperatures of the thermistors (1) can be realized, thereby avoiding the influence of hysteresis characteristics of the thermistor phase change material on the performance of the sensor, and enabling the micro-flow sensor to meet the engineering requirements for measuring extremely low flow.
Description
本发明涉及流体计量设备，特别是涉及一种基于相变材料的高灵敏度热式微流量传感器。The invention relates to fluid metering equipment, in particular to a high-sensitivity thermal micro-flow sensor based on phase change material.
微流量传感器是微流控***的重要组成部分，起到对微流体流动状态的监测并提供流体在微流道内流动信息的作用，实现在微全分析***中对微流体的精准控制，对微流控***的科学研究和工程应用具有重要意义。Micro flow sensors are an important component of microfluidic systems. They monitor the flow state of microfluids and provide information on the flow of fluids in microchannels, thereby achieving precise control of microfluidics in micro-total analysis systems. They are of great significance to the scientific research and engineering applications of microfluidic systems.
随着微机电***(Microelectromechanical Systems,MEMS)技术的发展，基于硅基微机械加工工艺制备的MEMS微流量传感器具有微型化、功耗低及性能高等优势，被广泛的应用于航空航天、临床医疗、生物制药及精细化工等领域。目前，测量微流体流量的方法及检测装置存在易受外界因素干扰、测量误差大且不连续等不足，并且分析***微型化进程及流式细胞术、颗粒分选、流动混合等新兴芯片实验室技术的进一步研究发展也对微流量传感器的性能提出了越来越高的测量需求。With the development of microelectromechanical systems (MEMS) technology, MEMS microflow sensors made based on silicon-based micromachining technology have the advantages of miniaturization, low power consumption and high performance, and are widely used in aerospace, clinical medicine, biopharmaceuticals and fine chemicals. At present, the methods and detection devices for measuring microfluidic flow have the disadvantages of being easily interfered by external factors, large measurement errors and discontinuity. In addition, the miniaturization process of the analysis system and the further research and development of emerging chip laboratory technologies such as flow cytometry, particle sorting, and flow mixing have also put forward higher and higher measurement requirements for the performance of microflow sensors.
MEMS微流量传感器按其传感原理大体可分为压阻式、压电式、热式三大类。压阻式传感器在低流量检测中表现出优异性能，但该类传感器易受温度、湿度的影响，从而限制了其在生物医学中的应用；压电式传感器常被用于振荡流检测且具有自供电的优点，但压电材料的高内阻特性使其无法用于静态流量检测。MEMS micro flow sensors can be roughly divided into three categories according to their sensing principles: piezoresistive, piezoelectric, and thermal. Piezoresistive sensors show excellent performance in low flow detection, but they are easily affected by temperature and humidity, which limits their application in biomedicine; piezoelectric sensors are often used for oscillating flow detection and have the advantage of self-power supply, but the high internal resistance of piezoelectric materials makes them unsuitable for static flow detection.
而热式传感器可实现气体和液体复用检测，并在高灵敏度微流量检测中拥有潜在应用价值。Thermal sensors can realize multiplexed detection of gases and liquids and have potential application value in high-sensitivity micro-flow detection.
热式微流量传感器通常由加热电阻与热敏电阻两部分组成，其实现途径主要包括热损失式、热分布式及热脉冲式三种构型方案。此类传感器的灵敏度、功耗等性能的优化主要取决于如何增加环境流体中的对流传热及最大化强制对流下的温度变化，需从热敏电阻敏感材料选择、传感器几何结构设计等方面综合考虑。Thermal micro-flow sensors usually consist of a heating resistor and a thermistor. The implementation methods mainly include three configuration schemes: heat loss, heat distribution, and heat pulse. The optimization of the sensitivity, power consumption and other performance of this type of sensor mainly depends on how to increase the convective heat transfer in the ambient fluid and maximize the temperature change under forced convection. It requires comprehensive consideration from the selection of thermistor sensitive materials and sensor geometric structure design.
常见敏感电阻由硅基半导体材料或金属铂制成，鲜有文献报道高绝对值电阻温度系数(Temperature Coefficient of Resistance,TCR)的超材料作为微流量传感
器的敏感材料。Common sensitive resistors are made of silicon-based semiconductor materials or metal platinum. There are few reports on metamaterials with high absolute temperature coefficient of resistance (TCR) as micro-flow sensors. Sensitive materials of the device.
目前针对热式微流量传感器的优化方法大多局限于对绝热衬底结构的改进以及对不同构型方案的整合，缺乏在核心热敏感材料电阻温度系数上的突破。导致热式微流量传感器的性能提升受到制约，严重阻碍了微流体技术的快速发展。At present, the optimization methods for thermal micro-flow sensors are mostly limited to the improvement of the insulation substrate structure and the integration of different configuration schemes, lacking breakthroughs in the temperature coefficient of resistance of the core thermal sensitive material. As a result, the performance improvement of thermal micro-flow sensors is restricted, which seriously hinders the rapid development of microfluidic technology.
发明内容Summary of the invention
发明人在实现本申请的过程中发现，现有的微流量传感器研究成果存在上述问题，因此希望有一种基于相变材料的高灵敏度热式微流量传感器能够解决现有MEMS热式流量传感器在微小流量下检测灵敏度低的问题。In the process of realizing this application, the inventors found that the existing research results of micro-flow sensors have the above-mentioned problems. Therefore, they hope to have a high-sensitivity thermal micro-flow sensor based on phase change material that can solve the problem of low detection sensitivity of existing MEMS thermal flow sensors under small flow rates.
本发明的目的是提出一种基于相变材料的高灵敏度热式微流量传感器，包括单晶衬底、流体层和两组设置有传感单元的固支梁；The purpose of the present invention is to provide a high-sensitivity thermal micro-flow sensor based on phase change material, comprising a single crystal substrate, a fluid layer and two groups of fixed beams provided with sensing units;
所述单晶衬底的上表面沉积有隔热介质膜；所述隔热介质膜的上方设置有流体层；隔热介质膜和流体层之间构建有供流体流通的微流道；所述两组固支梁分别悬空架设在微流道的上游和下游；所述固支梁包括用于支撑固支梁整体的二氧化硅隔离层、设置在固支梁的二氧化硅隔离层上表面的传感单元和用于封装传感单元的封装层；A heat-insulating dielectric film is deposited on the upper surface of the single crystal substrate; a fluid layer is arranged above the heat-insulating dielectric film; a microchannel for fluid circulation is constructed between the heat-insulating dielectric film and the fluid layer; the two groups of clamped beams are respectively suspended upstream and downstream of the microchannel; the clamped beams include a silicon dioxide isolation layer for supporting the entire clamped beam, a sensor unit arranged on the upper surface of the silicon dioxide isolation layer of the clamped beam, and a packaging layer for packaging the sensor unit;
所述传感单元包括用于加热流体温度的加热电阻、能够根据温度差异而产生不同电压信号的热敏电阻和用于连通电路的金属连线；所述加热电阻与外部供电电路连接；所述热敏电阻的材质为基于温度诱导电阻率突变的一阶相变材料，热敏电阻设置在金属连线上，并通过金属连线与外部检测电路连接；热敏电阻和加热电阻之间存在间隔。The sensing unit includes a heating resistor for heating the fluid temperature, a thermistor capable of generating different voltage signals according to the temperature difference, and a metal wire for connecting the circuit; the heating resistor is connected to an external power supply circuit; the material of the thermistor is a first-order phase change material based on temperature-induced resistivity mutation, the thermistor is arranged on the metal wire, and is connected to the external detection circuit through the metal wire; there is a gap between the thermistor and the heating resistor.
作为本发明的优选，加热电阻供电后产生热量，此时，微流道内的流体流动将导致位于两侧的热敏电阻各自所测量的温度存在差异；该差异导致两侧的热敏电阻的电阻值产生差异，外部检测电路将检测到两个不同的电压信号，将两个电压信号相减后作为最终输出的电压信号。As a preferred embodiment of the present invention, the heating resistor generates heat after power is supplied. At this time, the fluid flow in the microchannel will cause a difference in the temperature measured by the thermistors on both sides; this difference causes a difference in the resistance values of the thermistors on both sides, and the external detection circuit will detect two different voltage signals, which are subtracted from each other and used as the final output voltage signal.
作为本发明的优选，这些基于温度诱导电阻率突变的一阶相变材料为具有相变过程电阻率突变特性的金属氧化物及其掺杂材料。更为优选的，基于温度诱导电阻率突变的一阶相变材料为二氧化钒、V0.95-xCrxNb0.05O2、VO2/GaAs异质结等。As preferred embodiments of the present invention, these first-order phase change materials based on temperature-induced resistivity mutation are metal oxides and their doping materials having resistivity mutation characteristics during phase change. More preferably, the first-order phase change materials based on temperature-induced resistivity mutation are vanadium dioxide, V 0.95-x Cr x Nb 0.05 O 2 , VO 2 /GaAs heterojunction, etc.
作为本发明的优选，所述隔热介质膜为二氧化硅隔离层。所述上层流体层采用聚二甲基硅氧烷构建。
As a preferred embodiment of the present invention, the heat insulating medium film is a silicon dioxide isolation layer. The upper fluid layer is constructed of polydimethylsiloxane.
作为本发明的优选，所述两组固支梁镜像架设在微流道上，流体从微流道上游流到下游依次经过上游固支梁的热敏电阻、上游固支梁的加热电阻、下游固支梁的加热电阻和下游固支梁的热敏电阻。进一步的，所述加热电阻的材质为金。As a preferred embodiment of the present invention, the two groups of clamped beams are mirror-mounted on the microfluidic channel, and the fluid flows from the upstream to the downstream of the microfluidic channel and passes through the thermistor of the upstream clamped beam, the heating resistor of the upstream clamped beam, the heating resistor of the downstream clamped beam, and the thermistor of the downstream clamped beam in sequence. Further, the heating resistor is made of gold.
作为本发明的优选，所述上游加热电阻和下游加热电阻可分别由外部供电电路独立控制。As a preferred embodiment of the present invention, the upstream heating resistor and the downstream heating resistor can be independently controlled by external power supply circuits respectively.
作为本发明的优选，所述固支梁长度大于流道的宽度，连接流道两侧的单晶衬底。进一步的，所述单晶衬底选用单晶硅材料。As a preferred embodiment of the present invention, the length of the clamping beam is greater than the width of the flow channel, and the single crystal substrates on both sides of the flow channel are connected. Furthermore, the single crystal substrate is made of single crystal silicon material.
本发明的有益效果是本发明通过选择基于温度诱导电阻率突变的一阶相变材料作为热敏电阻的材质，利用其热致相变区间超高TCR特性实现了热敏电阻灵敏度大幅提升，突破非线性超材料在热式微流量传感器中的应用；进一步地，通过双加热电阻配置实现了上、下游固支梁上的传感单元单独控制各自的基于温度诱导电阻率突变的一阶相变材料热敏电阻处于最优工作温度，同时确保了热敏电阻阻值变化分别跟随基于温度诱导电阻率突变的一阶相变材料冷却曲线与加热曲线的主回路单调变化，避免了迟滞的影响。The beneficial effect of the present invention is that the present invention selects a first-order phase change material based on temperature-induced resistivity mutation as the material of the thermistor, and utilizes its ultra-high TCR characteristics in the thermal phase change range to achieve a significant improvement in the sensitivity of the thermistor, breaking through the application of nonlinear metamaterials in thermal micro-flow sensors; further, through the dual heating resistor configuration, the sensing units on the upstream and downstream fixed-support beams can independently control their respective first-order phase change material thermistors based on temperature-induced resistivity mutation to be at the optimal operating temperature, while ensuring that the resistance change of the thermistor follows the monotonous change of the main loop of the cooling curve and heating curve of the first-order phase change material based on the temperature-induced resistivity mutation, thereby avoiding the influence of hysteresis.
图1是本发明的结构示意图；Fig. 1 is a schematic structural diagram of the present invention;
图2是本发明的结构原理俯视图；Fig. 2 is a top view of the structural principle of the present invention;
图3是图2的A1-A1的剖视图；FIG3 is a cross-sectional view taken along line A1-A1 of FIG2 ;
图4是图2的A2-A2的剖视图；FIG4 is a cross-sectional view taken along line A2-A2 of FIG2 ;
图5是图2的B1-B1的剖视图；FIG5 is a cross-sectional view taken along line B1-B1 of FIG2 ;
图6是图2的B2-B2的剖视图；FIG6 is a cross-sectional view taken along line B2-B2 of FIG2 ;
图7是敏感材料为二氧化钒的两种构型(热损失与本发明双加热器式构型)流量传感器仿真结果图；FIG7 is a diagram showing simulation results of flow sensors with two configurations (heat loss and dual heater configuration of the present invention) in which the sensitive material is vanadium dioxide;
图8是敏感材料为铂的三种构型(热损失、热分布及本发明双加热器式构型)流量传感器仿真结果图。FIG8 is a diagram showing simulation results of flow sensors with three configurations (heat loss, heat distribution, and the dual-heater configuration of the present invention) whose sensitive material is platinum.
图中：1、热敏电阻；2、金属连线；3、封装层；4、加热电阻；5、流体层；6、隔热介质膜；7、单晶衬底。In the figure: 1. thermistor; 2. metal connection; 3. packaging layer; 4. heating resistor; 5. fluid layer; 6. thermal insulation dielectric film; 7. single crystal substrate.
本发明提出一种基于相变材料的高灵敏度热式微流量传感器，以下结合附图和实施例对本发明予以进一步说明。利用温度诱导电阻率突变的一阶相变材料在
相变过程电阻率突变特性，本发明实施例提供的基于相变材料的高灵敏度热式微流量传感器，可适用于微升或纳升的极低流量范围，可应用于化学分析、临床医疗、生物制药及精密制造等领域。The present invention proposes a highly sensitive thermal micro flow sensor based on phase change material, which is further described below in conjunction with the accompanying drawings and embodiments. The resistivity mutation characteristic of the phase change process, the high-sensitivity thermal micro-flow sensor based on phase change material provided in the embodiment of the present invention can be applicable to the extremely low flow range of microliters or nanoliters, and can be applied to chemical analysis, clinical medicine, biopharmaceuticals and precision manufacturing and other fields.
实施例1Example 1
如图1所示的基于相变材料的高灵敏度热式微流量传感器，包括下层为单晶硅材料的单晶衬底7、微流道的上层为采用聚二甲基硅氧材料的流体层5和两组设置有传感单元的固支梁；如图5和6所示，固支梁架设在由单晶衬底7和流体层5之间开设的微流道上且固支梁长度大于流道的宽度，连接流道两侧的单晶衬底，两组固支梁分悬空别架设在微流道的上下游；固支梁的下层为材料选用二氧化硅的隔热介质膜，起到支撑固支梁整体的作用；加热电阻和金属连线均设置在固支梁的隔热介质膜上表面；热敏电阻设置在金属连线上，上层为二氧化硅材质的封装层。As shown in FIG1 , a highly sensitive thermal micro-flow sensor based on phase change material comprises a single crystal substrate 7 whose lower layer is single crystal silicon material, a fluid layer 5 made of polydimethylsiloxane material and two groups of fixed beams provided with sensing units on the upper layer of the microchannel; as shown in FIGS. 5 and 6 , the fixed beam is mounted on the microchannel opened between the single crystal substrate 7 and the fluid layer 5 and the length of the fixed beam is greater than the width of the channel, connecting the single crystal substrates on both sides of the channel, and the two groups of fixed beams are suspended and respectively mounted upstream and downstream of the microchannel; the lower layer of the fixed beam is a heat-insulating dielectric film made of silicon dioxide, which plays a role in supporting the fixed beam as a whole; the heating resistor and the metal connection are both arranged on the upper surface of the heat-insulating dielectric film of the fixed beam; the thermistor is arranged on the metal connection line, and the upper layer is a packaging layer made of silicon dioxide.
如图2和3所示，本实施例加热电阻的材质为金，长度为50μm，宽度为4μm，厚度H1＝0.2μm，上、下游两个加热电阻的间距D1＝38μm；热敏电阻的材质为基于温度诱导电阻率突变的一阶相变材料，在本实施例中选用二氧化钒；二氧化钒相转变温度在68℃，其具有响应率高、电阻温度系数高及良好的MEMS工艺兼容性等优点，其常温下具有高达-27000ppm/K的TCR，而在IMT区间TCR最高可达约-700000ppm/K。因此，VO2在高灵敏度热流量检测中有巨大的潜在应用价值。热敏电阻的电阻率在可逆热致相变区间内呈现三个数量级的变化，长度为16μm，宽度为16μm，厚度H2＝0.2μm，上、下游两个热敏电阻的间距D2＝98μm；二氧化硅隔离层厚度d1＝0.5μm，二氧化硅封装层厚度d1＝1.5μm。As shown in Figures 2 and 3, the material of the heating resistor in this embodiment is gold, with a length of 50μm, a width of 4μm, a thickness of H1 = 0.2μm, and a spacing D1 = 38μm between the upstream and downstream heating resistors; the material of the thermistor is a first-order phase change material based on temperature-induced resistivity mutation, and vanadium dioxide is selected in this embodiment; the phase transition temperature of vanadium dioxide is 68°C, and it has the advantages of high response rate, high resistance temperature coefficient and good MEMS process compatibility, etc. It has a TCR of up to -27000ppm/K at room temperature, and the TCR in the IMT range can reach up to about -700000ppm/K. Therefore, VO2 has great potential application value in high-sensitivity heat flow detection. The resistivity of the thermistor changes by three orders of magnitude in the reversible thermoinduced phase transition range. The length is 16 μm, the width is 16 μm, the thickness is H 2 =0.2 μm, and the distance between the upstream and downstream thermistors is D 2 =98 μm. The thickness of the silicon dioxide isolation layer is d 1 =0.5 μm, and the thickness of the silicon dioxide encapsulation layer is d 1 =1.5 μm.
在二氧化硅隔离层上设置加热电阻与热敏电阻，如图2所示，镜像架设固支梁时依次按照热敏电阻、加热电阻、加热电阻、热敏电阻的顺序顺流方向布置在流道中。工作时，通过外电路对两个加热电阻进行供电，供电后加热电阻产生热量。此时，微流道内的流体流动导致位于两侧的热敏电阻各自所测量的流体温度存在差异；该差异导致两侧的热敏电阻的电阻值产生差异，外部检测电路将检测到两个不同的电压信号。再将这两个电压信号相减后作为最终输出的电压信号，再将最终输出的电压信号转换为对应的流体流速，由此实现热式微流量测量原理。A heating resistor and a thermistor are arranged on the silicon dioxide isolation layer, as shown in Figure 2. When the fixed support beam is mirrored, they are arranged in the flow channel in the order of thermistor, heating resistor, heating resistor, and thermistor in the downstream direction. During operation, the two heating resistors are powered by an external circuit, and the heating resistors generate heat after power supply. At this time, the flow of fluid in the microchannel causes a difference in the fluid temperature measured by the thermistors on both sides; this difference causes a difference in the resistance value of the thermistors on both sides, and the external detection circuit will detect two different voltage signals. The two voltage signals are then subtracted from each other as the final output voltage signal, and the final output voltage signal is then converted into the corresponding fluid flow rate, thereby realizing the thermal micro-flow measurement principle.
本发明的效果可结合仿真结果作进一步说明：The effect of the present invention can be further explained in conjunction with the simulation results:
1、仿真内容
1. Simulation content
利用商用仿真软件COMSOL Multiphysics 5.6对本发明实施例1中，微流体(空气)流量范围为0～1μL·min-1的传感器输出电压信号进行仿真计算，并与相同热敏电阻材料、不同构型的传感器输出电压进行比较，结果如图7所示。The commercial simulation software COMSOL Multiphysics 5.6 was used to simulate and calculate the output voltage signal of the sensor with a microfluid (air) flow rate range of 0 to 1 μL·min -1 in Example 1 of the present invention, and compared with the output voltage of sensors with the same thermistor material and different configurations. The results are shown in FIG7 .
利用商用仿真软件COMSOL Multiphysics 5.6对本发明实施例1中，微流体(空气)流量范围为0～1μL·min-1的传感器输出电压信号进行仿真计算，保持其他仿真条件一致，改变热敏电阻的材料为铂，并比较三种构型的流量传感器输出电压信号，结果如图8所示。The commercial simulation software COMSOL Multiphysics 5.6 was used to simulate the sensor output voltage signal in the microfluid (air) flow range of 0 to 1 μL·min -1 in Example 1 of the present invention. The other simulation conditions were kept the same, the material of the thermistor was changed to platinum, and the output voltage signals of the flow sensors of the three configurations were compared. The results are shown in FIG8 .
2、仿真结果2. Simulation results
如图7所示，本发明提出的两个加热电阻分别由外部供电电路独立控制(双加热器式)的基于相变材料的高灵敏度热式微流量传感器在流量范围内0～0.2μL·min-1呈线性响应，灵敏度高达1.34V/(μL·min-1)，约为热损失式流量传感器灵敏度16.69mV/(μL·min-1)的80.50倍。当流量进一步增大时，灵敏度为在较高的流量范围内饱和但灵敏度仍能达到35.04mV/(μL·min-1)，表明两个加热电阻分别由外部供电电路独立控制(双加热器式)构型能明显提高传感器的灵敏度，具有在极低流量下的潜在应用前景。As shown in FIG7 , the high-sensitivity thermal micro-flow sensor based on phase change material in which two heating resistors are independently controlled by an external power supply circuit (dual heater type) proposed by the present invention has a linear response within the flow range of 0 to 0.2 μL·min -1 , and a sensitivity of up to 1.34V/(μL·min -1 ), which is about 80.50 times the sensitivity of the heat loss flow sensor of 16.69mV/(μL·min -1 ). When the flow rate increases further, the sensitivity is saturated within a higher flow range, but the sensitivity can still reach 35.04mV/(μL·min -1 ), indicating that the configuration of two heating resistors independently controlled by an external power supply circuit (dual heater type) can significantly improve the sensitivity of the sensor, and has potential application prospects at extremely low flow rates.
如图8所示，在相同敏感材料的条件下，相较于其余两种常见构型，基于本发明两个加热电阻分别由外部供电电路独立控制(双加热器式)构型的流量传感器检测灵敏度更高，也说明了本发明选用的敏感材料在不同构型中的普适性；结合图7和图8可知，相同构型下，与基于Pt的流量传感器相比较，基于VO2的流量传感器在检测极低流体流速的灵敏度上有了显著的提高，表明VO2热致相变区间超高TCR特性可以实现传感器灵敏度的大幅提升，理论上论证了非线性超材料在高灵敏度热式微流量传感器中应用的可行性。As shown in Figure 8, under the condition of the same sensitive material, compared with the other two common configurations, the flow sensor based on the configuration in which the two heating resistors are independently controlled by the external power supply circuit (dual heater type) of the present invention has higher detection sensitivity, which also illustrates the universality of the sensitive materials selected by the present invention in different configurations; combined with Figures 7 and 8, it can be seen that under the same configuration, compared with the Pt-based flow sensor, the VO2 -based flow sensor has a significant improvement in the sensitivity of detecting extremely low fluid flow rates, indicating that the ultra-high TCR characteristics of the VO2 thermal phase change range can achieve a significant improvement in sensor sensitivity, and theoretically demonstrates the feasibility of using nonlinear metamaterials in high-sensitivity thermal micro-flow sensors.
综上所示本发明所设计的基于相变材料的高灵敏度热式微流量传感器通过选择非线性相变材料作为敏感材料，结合双加热器结构实现了独立控温，避免了滞回的影响，大幅提升了传感器的灵敏度，其体积小、分辨率高，可适用于微升或纳升的极低流量范围，可应用于化学分析、临床医疗、生物制药及精密制造等领域。
In summary, the high-sensitivity thermal micro-flow sensor based on phase change material designed by the present invention selects nonlinear phase change material as the sensitive material and combines it with a dual heater structure to achieve independent temperature control, avoid the influence of hysteresis, and greatly improve the sensitivity of the sensor. It has a small size and high resolution, and can be used in an extremely low flow range of microliters or nanoliters. It can be used in chemical analysis, clinical medicine, biopharmaceuticals, precision manufacturing and other fields.
Claims (10)
- 一种基于相变材料的高灵敏度热式微流量传感器，其特征在于，包括单晶衬底(7)、流体层(5)和两组设置有传感单元的固支梁；A high-sensitivity thermal micro-flow sensor based on phase change material, characterized in that it comprises a single crystal substrate (7), a fluid layer (5) and two groups of fixed beams provided with sensing units;所述单晶衬底(7)的上表面沉积有隔热介质膜(6)；所述隔热介质膜(6)的上方设置有流体层(5)；隔热介质膜(6)和流体层(5)之间构建有供流体流通的微流道；所述两组固支梁分别悬空架设在微流道的上游和下游；所述固支梁包括用于支撑固支梁整体的二氧化硅隔离层、设置在固支梁的二氧化硅隔离层上表面的传感单元和用于封装传感单元的封装层(3)；A heat-insulating dielectric film (6) is deposited on the upper surface of the single crystal substrate (7); a fluid layer (5) is arranged above the heat-insulating dielectric film (6); a microchannel for fluid circulation is constructed between the heat-insulating dielectric film (6) and the fluid layer (5); the two groups of fixed-support beams are respectively suspended upstream and downstream of the microchannel; the fixed-support beams include a silicon dioxide isolation layer for supporting the entire fixed-support beam, a sensor unit arranged on the upper surface of the silicon dioxide isolation layer of the fixed-support beam, and a packaging layer (3) for packaging the sensor unit;所述传感单元包括用于加热流体温度的加热电阻(4)、能够根据温度差异而产生不同电压信号的热敏电阻(1)和用于连通电路的金属连线(2)；所述加热电阻(4)与外部供电电路连接；所述热敏电阻(1)的材质为基于温度诱导电阻率突变的一阶相变材料，热敏电阻(1)设置在金属连线(2)上，并通过金属连线(2)与外部检测电路连接；热敏电阻(1)和加热电阻(4)之间存在间隔。The sensing unit comprises a heating resistor (4) for heating the fluid temperature, a thermistor (1) capable of generating different voltage signals according to temperature differences, and a metal connection line (2) for connecting the circuit; the heating resistor (4) is connected to an external power supply circuit; the material of the thermistor (1) is a first-order phase change material based on temperature-induced resistivity mutation, the thermistor (1) is arranged on the metal connection line (2), and is connected to the external detection circuit through the metal connection line (2); there is a gap between the thermistor (1) and the heating resistor (4).
- 根据权利要求1所述的一种基于相变材料的高灵敏度热式微流量传感器，其特征在于，所述加热电阻供电后产生热量，微流道内的流体流动导致位于两侧的热敏电阻各自所测量的流体温度存在差异；该差异导致两侧的热敏电阻的电阻值产生差异，继而使外部检测电路检测到两个不同的电压信号，将两个电压信号相减后作为最终输出的电压信号。According to claim 1, a high-sensitivity thermal micro-flow sensor based on phase change material is characterized in that the heating resistor generates heat after power is supplied, and the fluid flow in the microchannel causes a difference in the fluid temperature measured by the thermistors on both sides; this difference causes a difference in the resistance values of the thermistors on both sides, and then the external detection circuit detects two different voltage signals, and the two voltage signals are subtracted as the final output voltage signal.
- 根据权利要求1所述的一种基于相变材料的高灵敏度热式微流量传感器，其特征在于，所述两组固支梁镜像架设在微流道上，流体从微流道上游流到下游依次经过上游固支梁的热敏电阻、上游固支梁的加热电阻、下游固支梁的加热电阻和下游固支梁的热敏电阻。According to a high-sensitivity thermal micro-flow sensor based on phase change material as described in claim 1, it is characterized in that the two groups of clamped beams are mirror-mounted on the microchannel, and the fluid flows from upstream to downstream of the microchannel and passes through the thermistor of the upstream clamped beam, the heating resistor of the upstream clamped beam, the heating resistor of the downstream clamped beam and the thermistor of the downstream clamped beam in sequence.
- 根据权利要求3所述的一种基于相变材料的高灵敏度热式微流量传感器，其特征在于，所述上游固支梁的加热电阻和下游固支梁的加热电阻分别由外部供电电路独立控制。According to a high-sensitivity thermal micro-flow sensor based on phase change material as described in claim 3, it is characterized in that the heating resistor of the upstream clamped beam and the heating resistor of the downstream clamped beam are independently controlled by an external power supply circuit.
- 根据权利要求1所述的一种基于相变材料的高灵敏度热式微流量传感器，其特征在于，所述固支梁长度大于流道的宽度，连接流道两侧的单晶衬底。According to a high-sensitivity thermal micro-flow sensor based on phase change material as described in claim 1, it is characterized in that the length of the clamped beam is greater than the width of the flow channel and connects the single crystal substrates on both sides of the flow channel.
- 根据权利要求1所述的一种基于相变材料的高灵敏度热式微流量传感器，其特征在于，所述加热电阻的材质为金。 According to the high-sensitivity thermal micro-flow sensor based on phase change material according to claim 1, it is characterized in that the material of the heating resistor is gold.
- 根据权利要求1所述的一种基于相变材料的高灵敏度热式微流量传感器，其特征在于，所述单晶衬底(7)选用单晶硅材料。The high-sensitivity thermal micro-flow sensor based on phase change material according to claim 1 is characterized in that the single crystal substrate (7) is made of single crystal silicon material.
- 根据权利要求1所述的一种基于相变材料的高灵敏度热式微流量传感器，其特征在于，所述隔热介质膜(6)为二氧化硅材料。According to the high-sensitivity thermal micro-flow sensor based on phase change material as claimed in claim 1, it is characterized in that the thermal insulation dielectric film (6) is made of silicon dioxide material.
- 根据权利要求1所述的一种基于相变材料的高灵敏度热式微流量传感器，其特征在于，所述流体层(5)采用聚二甲基硅氧烷材料。According to the high-sensitivity thermal micro-flow sensor based on phase change material as claimed in claim 1, it is characterized in that the fluid layer (5) is made of polydimethylsiloxane material.
- 根据权利要求1所述的一种基于相变材料的高灵敏度热式微流量传感器，其特征在于，所述基于温度诱导电阻率突变的一阶相变材料为具有相变过程电阻率突变特性的金属氧化物及其掺杂材料。 According to a high-sensitivity thermal micro-flow sensor based on phase change material as described in claim 1, it is characterized in that the first-order phase change material based on temperature-induced resistivity mutation is a metal oxide and its doped material having the resistivity mutation characteristic of the phase change process.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20090016403A1 (en) * | 2007-07-09 | 2009-01-15 | Chih-Chang Chen | Micromachined gas and liquid concentration sensor and method of making the same |
| CN104280085A (en) * | 2014-10-24 | 2015-01-14 | 中国电子科技集团公司第三十八研究所 | Gas flow sensor and manufacturing method thereof |
| CN105865552A (en) * | 2016-04-08 | 2016-08-17 | 东南大学 | Integrated array type film gas flow sensor based on micro-electromechanical systems (MEMS) process and processing method thereof |
| US20180299308A1 (en) * | 2015-10-05 | 2018-10-18 | Wisenstech Ltd. | Composite mems flow sensor on silicon-on-insulator device and method of making the same |
| CN109154516A (en) * | 2016-03-30 | 2019-01-04 | 江森自控科技公司 | liquid detecting system |
| CN112889013A (en) * | 2018-09-06 | 2021-06-01 | 可口可乐公司 | Flow control module with thermal mass flow meter |
| CN115452076A (en) * | 2022-09-28 | 2022-12-09 | 浙江大学 | High-sensitivity thermal micro-flow sensor based on phase-change material |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6208254B1 (en) * | 1999-09-15 | 2001-03-27 | Fluid Components Intl | Thermal dispersion mass flow rate and liquid level switch/transmitter |
| JPWO2015076117A1 (en) * | 2013-11-20 | 2017-03-16 | 株式会社村田製作所 | Thermal flow sensor |
| DE102017216656A1 (en) * | 2017-09-20 | 2019-03-21 | Robert Bosch Gmbh | Method and device for controlling a heating element of a sensor element of an air mass sensor for a vehicle and air mass sensor system for a vehicle |
| CN110274649B (en) * | 2019-06-13 | 2020-09-01 | 武汉大学 | Thermal temperature difference type flow sensor based on MEMS technology and preparation method thereof |
-
2022
- 2022-09-28 CN CN202211202622.3A patent/CN115452076A/en active Pending
-
2023
- 2023-09-14 WO PCT/CN2023/118785 patent/WO2024067123A1/en unknown
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20090016403A1 (en) * | 2007-07-09 | 2009-01-15 | Chih-Chang Chen | Micromachined gas and liquid concentration sensor and method of making the same |
| CN104280085A (en) * | 2014-10-24 | 2015-01-14 | 中国电子科技集团公司第三十八研究所 | Gas flow sensor and manufacturing method thereof |
| US20180299308A1 (en) * | 2015-10-05 | 2018-10-18 | Wisenstech Ltd. | Composite mems flow sensor on silicon-on-insulator device and method of making the same |
| CN109154516A (en) * | 2016-03-30 | 2019-01-04 | 江森自控科技公司 | liquid detecting system |
| CN105865552A (en) * | 2016-04-08 | 2016-08-17 | 东南大学 | Integrated array type film gas flow sensor based on micro-electromechanical systems (MEMS) process and processing method thereof |
| CN112889013A (en) * | 2018-09-06 | 2021-06-01 | 可口可乐公司 | Flow control module with thermal mass flow meter |
| CN115452076A (en) * | 2022-09-28 | 2022-12-09 | 浙江大学 | High-sensitivity thermal micro-flow sensor based on phase-change material |
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