CN104482971A - Thermal flow sensor on basis of MEMS (micro-electromechanical systems) technology - Google Patents
Thermal flow sensor on basis of MEMS (micro-electromechanical systems) technology Download PDFInfo
- Publication number
- CN104482971A CN104482971A CN201410742115.8A CN201410742115A CN104482971A CN 104482971 A CN104482971 A CN 104482971A CN 201410742115 A CN201410742115 A CN 201410742115A CN 104482971 A CN104482971 A CN 104482971A
- Authority
- CN
- China
- Prior art keywords
- electrode pad
- temperature element
- temperature
- contact conductor
- underboarding
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Landscapes
- Measuring Volume Flow (AREA)
Abstract
The invention provides a thermal flow sensor on the basis of an MEMS (micro-electromechanical systems) technology. Heat can be dissipated by a heating element to tested liquid, and heat of the liquid can be detected by temperature measuring elements, so that flow can be measured. The thermal flow sensor comprises the heating element, two first groups of temperature measuring elements, two second groups of temperature measuring elements, a corresponding heating control circuit and a corresponding signal detecting circuit. The two first groups of temperature measuring elements are positioned on an upstream side of the heating element and are separated from the heating element by different distances, and the two second groups of temperature measuring elements are symmetrically arranged on a downstream side of the heating element. Compared with the traditional thermal flow sensor, the thermal flow sensor has the advantages that the thermal flow sensor is high in sensitivity and wide in range, is manufactured by the aid of the micro-electromechanical machining technology, is low in pressure loss and high in thermal response speed and reliability and is small and light, and the like.
Description
Technical field
The invention belongs to sensor field and microelectromechanical systems (Micro Electro MechanicalSystem, MEMS) field, particularly, relate to a kind of thermal flow rate sensor based on MEMS technology, be particularly useful for the occasion in spacecraft propulsion system, small-flow gas being had to high sensitivity, high-acruracy survey demand.
Background technology
Thermal type flow measuring utilizes the heat exchange relationship between heater element and fluid be positioned in detected fluid to carry out the technology of flow measurement.Thermal flow rate sensor is divided into wind gage formula and calorimetric (also known as thermal type or heat distribution formula) two kinds of normal method usually:
(1) principle of work of wind gage formula flow sensor is based upon in King's Law theoretical foundation, and this metering system is that the heat dissipation degree of heater strip in process fluid flow is as flow measurement foundation.Its principal character is, sensor has a heater strip, and the heat that heater strip produces in a fluid is pulled away, directly or indirectly measure heat dissipation capacity number can demarcate the size of flow velocity.But when the shortcoming of this sensor is low flow velocity, sensitivity is low, poor stability.
(2) measuring principle of calorimetric flow sensor then detects flow velocity size with the Temperature Distribution detecting heating element (thermal source) both sides in process fluid flow.Its principal character is, sensor provides heating by a thermal source, in the upstream and downstream both sides equidistant apart from thermal source along flow velocity direction, has a temperature measuring unit respectively.Temperature measuring unit can be thermal resistance or thermoelectric pile etc.The upstream and downstream temperature difference when certain flow is utilized to measure the size of flow velocity.Compared with wind gage formula, easily occur saturated when the shortcoming of calorimetric flow sensor is high flow rate.
Due to calorimetric sensor there is high flow rate under export easily saturated weakness, its flow measurement range can not reach very wide scope, thus limits it in the application needing high sensitivity and high range than occasion.For the flow measurement demand of high range ratio under low discharge scope, the existing patent documentation CN101680788A (applying date: 2008.04.22, denomination of invention: thermal flow meter) and the CN101782410A (applying date: 2009.01.20, denomination of invention: a kind of thermal flow meter of micro electro mechanical system) scheme that have employed in conjunction with wind gage formula and calorimetric multiple measurement realizes higher sensitivity and wider range ratio, by subsequent process circuit flow range and measurement result calculated and judge, but, not only the design of sensor subsequent process circuit is complicated for such mode, and integral manufacturing cost is high.
Summary of the invention
The technical problem to be solved in the present invention is: for the problem of the aspect deficiencies such as standing crop thermal flow rate sensor measurement range (range ratio), sensitivity, there is provided a kind of novel thermal flow rate sensor based on MEMS technology, to realize the measurement range (range ratio) wider than standing crop thermal flow rate sensor and higher sensitivity.
For solving the problems of the technologies described above, the technical solution used in the present invention comprises:
According to an aspect of the present invention, which provide a kind of thermal flow rate sensor based on MEMS technology, comprise: underboarding, the first electric insulation layer be covered on underboarding, the wiring layer be arranged on the first electric insulation layer, the second electric insulation layer be covered on wiring layer, the first fixed resistance, the second fixed resistance, amplifier, triode and first instrument amplifier, wherein
The back side of underboarding is formed with cavity, and the first electric insulation layer is partly exposed from the back side of underboarding, the part that first electric insulation layer, wiring layer and the second electric insulation layer are positioned on cavity forms diaphragm region, underboarding comprises the first electrode pad being positioned at first side, 3rd electrode pad, 5th electrode pad, 7th electrode pad, 9th electrode pad, and be positioned at the second electrode pad of second side, 4th electrode pad, 6th electrode pad, 8th electrode pad, tenth electrode pad and the 11 electrode pad, wherein, first electrode pad and the second electrode pad, 3rd electrode pad and the 4th electrode pad, 5th electrode pad and the 6th electrode pad, 7th electrode pad and the 8th electrode pad, and the 9th electrode pad and the tenth electrode pad arrange symmetrically relative to the flow direction of fluid,
Wiring layer comprises: be positioned at the heater element in the middle part of underboarding, and the first end of heater element is connected to the first electrode pad by contact conductor, and its second end is connected to the second electrode pad by contact conductor, first temperature element to the second temperature element pair, first temperature element is arranged in heater element upstream and downstream to the second temperature element symmetrically to relative to heater element, described upstream and downstream with the flow direction of fluid for benchmark, first temperature element is to comprising the first temperature element and the second temperature element, second temperature element is to comprising the 3rd temperature element and the 4th temperature element, and the first end of the first temperature element and the second end are connected to the 9th electrode pad and the tenth electrode pad respectively by contact conductor, the first end of the second temperature element and the second end are connected to the 7th electrode pad and the 8th electrode pad respectively by contact conductor, the first end of the 3rd temperature element and the second end are connected to the 3rd electrode pad and the 4th electrode pad respectively by contact conductor, the first end of the 4th temperature element and the second end are connected to the 5th electrode pad and the 6th electrode pad respectively by contact conductor, and auxiliary temperature element, it is positioned at the upstream of diaphragm region, and the first end of auxiliary temperature element is connected to the second end of heater element, and the second end of auxiliary temperature element is connected to the 11 electrode pad by contact conductor, and each temperature element is formed and the resistance pattern with bending shape parallel by more than two or two,
The collector of triode is connected with the first outside power supply, and the base stage of triode is connected to the output terminal of amplifier, and the emitter of triode is connected to the second electrode pad; One end of first fixed resistance is connected to the first electrode pad, other end ground connection; One end of second fixed resistance is connected to the 11 electrode pad, other end ground connection; The positive input terminal of amplifier is connected between heater element and the first fixed resistance, and its negative input end is connected between auxiliary temperature element and the second fixed resistance; 9th electrode pad and the 5th electrode pad are connected to outside second source by contact conductor jointly; Tenth electrode pad is connected with the 3rd electrode pad; 4th electrode pad and the 8th electrode pad common ground; 6th electrode pad is connected with the 7th electrode pad; The positive input terminal of first instrument amplifier is connected between the first temperature element and the 3rd temperature element, and negative input end is connected between the second temperature element and the 4th temperature element, and its output terminal is as the output terminal of described thermal flow rate sensor.
According to another aspect of the present invention, which provide a kind of thermal flow rate sensor based on MEMS technology, comprise underboarding, the first electric insulation layer be covered on underboarding, the wiring layer be arranged on the first electric insulation layer, the second electric insulation layer be covered on wiring layer, the first fixed resistance, the second fixed resistance, amplifier, triode, first instrument amplifier, second instrument amplifier and the 3rd instrument amplifier, wherein
The back side of underboarding is formed with cavity, and the first electric insulation layer is partly exposed from the back side of underboarding, the part that first electric insulation layer, wiring layer and the second electric insulation layer are positioned on cavity forms diaphragm region, underboarding comprises: the first electrode pad being positioned at first side, 3rd electrode pad, 4th electrode pad, 5th electrode pad, 6th electrode pad, 11 electrode pad, 12 electrode pad, 13 electrode pad and the 14 electrode pad, and be positioned at the second electrode pad of second side, 7th electrode pad, 8th electrode pad, 9th electrode pad, tenth electrode pad, 15 electrode pad, 16 electrode pad, 17 electrode pad, 18 electrode pad and the 19 electrode pad, wherein, first electrode pad and the second electrode pad are arranged symmetrically relative to the flow direction of fluid,
Wiring layer comprises: be positioned at the heater element in the middle part of underboarding, and the first end of heater element is connected to the first electrode pad by contact conductor, and its second end is connected to the second electrode pad by contact conductor, first temperature element pair, second temperature element pair, 3rd temperature element to and the 4th temperature element pair, first temperature element pair and the second temperature element pair, 3rd temperature element pair and the 4th temperature element are to the upstream and downstream being arranged in heater element respectively symmetrically, described upstream and downstream with the flow direction of fluid for benchmark, first temperature element is to comprising the first temperature element and the second temperature element, second temperature element is to comprising the 3rd temperature element and the 4th temperature element, 3rd temperature element is to comprising the 5th temperature element and the 6th temperature element, 4th temperature element is to comprising the 7th temperature element and the 8th temperature element, and the first end of the first temperature element and the second end are connected to the 11 electrode pad and the 14 electrode pad respectively by contact conductor, first end and second end of the second temperature element are connected to the 12 electrode pad and the 13 electrode pad respectively by contact conductor, the first end of the 3rd temperature element and the second end are connected to the 3rd electrode pad and the 6th electrode pad respectively by contact conductor, the first end of the 4th temperature element and the second end are connected to the 4th electrode pad and the 5th electrode pad respectively by contact conductor, first end and second end of the 5th temperature element are connected to the 15 electrode pad and the 18 electrode pad respectively by contact conductor, first end and second end of the 6th temperature element are connected to the 16 electrode pad and the 17 electrode pad respectively by contact conductor, the first end of the 7th temperature element and the second end are connected to the 7th electrode pad and the tenth electrode pad respectively by contact conductor, the first end of the 8th temperature element and the second end are connected to the 8th electrode pad and the 9th electrode pad respectively by contact conductor, and auxiliary temperature element, it is positioned at the upstream of diaphragm region, and the first end of auxiliary temperature element is connected to the second end of heater element, and the second end of auxiliary temperature element is connected to the 19 electrode pad by contact conductor, and each temperature element is formed and the resistance pattern with bending shape parallel by more than two or two,
The collector of triode is connected with the first outside power supply, and the base stage of triode is connected to the output terminal of amplifier, and the emitter of triode is connected to the second electrode pad; One end of first fixed resistance is connected to the first electrode pad, other end ground connection; One end of second fixed resistance is connected to the 19 electrode pad, other end ground connection; The positive input terminal of amplifier is connected between heater element and the first fixed resistance, and its negative input end is connected between auxiliary temperature element and the second fixed resistance; 11 electrode pad and the 4th electrode pad are connected to outside second source by contact conductor jointly; 3rd electrode pad is connected with the 14 electrode pad; 6th electrode pad and the 13 electrode pad common ground; 5th electrode pad is connected with the 12 electrode pad; The negative input end of first instrument amplifier is connected between the first temperature element and the 3rd temperature element, and positive input terminal is connected between the second temperature element and the 4th temperature element, and its output terminal is connected to the negative input end of the 3rd instrument amplifier; 8th electrode pad and the 15 electrode pad are connected to outside second source jointly; 7th electrode pad is connected with the 18 electrode pad; Tenth electrode pad and the 17 electrode pad common ground; 9th electrode pad is connected with the 16 electrode pad; The positive input terminal of second instrument amplifier is connected between the 5th temperature element and the 7th temperature element, and negative input end is connected between the 8th temperature element and the 6th temperature element, and its output terminal is connected to the positive input terminal of the 3rd instrument amplifier; The output terminal of the 3rd instrument amplifier is as the output terminal of described thermal flow rate sensor.
Further, described heater element is resistance or thermo-sensitive material, and the wiring pattern of described heater element is formed by multiple bending pattern, has the bending part of more than 2.
Further, the width of the contact conductor of described heater element is wider than the wiring width of described heater element, the wiring area of described heater element and the wiring area of the contact conductor flow direction all about fluid is symmetrical, and is arranged vertically with the flow direction of fluid.
Further, described auxiliary temperature element and all temperature elements can be all resistance or thermo-sensitive material or thermoelectric pile.
Further, described underboarding can be silicon, glass or polymkeric substance.
Compared with prior art, the flow sensor based on hot type principle according to the present invention has following Advantageous Effects:
Thermal flow rate sensor based on MEMS technology provided by the present invention, by arranging multipair (two pairs or more) temperature element separately at heater element upstream and downstream, in conjunction with corresponding heating control circuit and signal processing circuit, flow measurement range (higher range ratio) can be improved.
Each temperature element, to the arrangement of the temperature element walked abreast by employing two (or more than two), is more conducive to adopting bridge diagram to carry out signal extraction, and improves the sensitivity of measuring-signal.
Employing MEMS technology is processed, and the flow-sensitive area size of thermal flow rate sensor can be made to reach grade, and its volume is little, thermal capacitance is little thus improve the thermal response speed of thermal flow rate sensor.
In addition, thermal flow rate sensor based on MEMS technology provided by the present invention utilizes semiconductor packaging to make, not only there is the advantage that range ability is wide, highly sensitive, also there is the advantages such as measuring accuracy is high, thermal response speed is fast, the pressure loss is little, size is little, lightweight.
Accompanying drawing explanation
Fig. 1 is the part plan structural representation of thermal flow rate sensor in accordance with a preferred embodiment of the present invention;
Fig. 2 is the X-X' schematic cross-section of the sensor in Fig. 1;
Fig. 3 is the Temperature Distribution schematic diagram of the diaphragm region, sensors X-X' cross section in Fig. 1;
Fig. 4 is the circuit diagram of the thermal flow rate sensor in Fig. 1;
Fig. 5 is the part plan structural representation of the thermal flow rate sensor according to another preferred embodiment of the present invention;
Fig. 6 is the X-X' schematic cross-section of the sensor in Fig. 5;
Fig. 7 is the Temperature Distribution schematic diagram of the diaphragm region, sensors X-X' cross section in Fig. 5;
Fig. 8 is the circuit diagram of the thermal flow rate sensor in Fig. 5;
Fig. 9 is the output curve diagram of the thermal flow rate sensor in Fig. 1 and Fig. 5;
Figure 10 is the output sensitivity curve map of the thermal flow rate sensor in Fig. 1 and Fig. 5.
Embodiment
Below in conjunction with the drawings and specific embodiments, the thermal flow rate sensor based on MEMS technology according to the present invention is further described in detail.
The present invention adopts calorimetric (thermal type or heat distribution formula) flow measurement principle, namely utilizes the heater element convection cell heating be arranged in fluid, carrys out measuring flow by the temperature difference of heater element upstream and downstream.The present invention is by arranging multipair (two pairs or more) temperature element separately at heater element upstream and downstream, heater element carries out computer heating control by external circuit, utilize constant difference mode convection cell to heat, then combine outside signal processing circuit to improve flow measurement range and flow measurement sensitivity.
Shown in Fig. 1 to Fig. 4 is thermal flow rate sensor in accordance with a preferred embodiment of the present invention.As shown in the figure, should comprise based on the thermal flow rate sensor of MEMS technology: underboarding 1, the first electric insulation layer 2a be covered on underboarding 1, the wiring layer be arranged on the first electric insulation layer 2a, the second electric insulation layer 2b be covered on wiring layer, the first fixed resistance 100, second fixed resistance 101, amplifier 102, triode 109 and first instrument amplifier 103.
The back side of underboarding 1 is formed with cavity, and the first electric insulation layer 2a is partly exposed from the back side of underboarding 1.The part that first electric insulation layer 2a, wiring layer and the second electric insulation layer 2b are positioned on cavity forms diaphragm region 3 (as shown in Figure 2).Underboarding 1 comprises the first electrode pad 11, the 3rd electrode pad 13, the 5th electrode pad 15, the 7th electrode pad 17, the 9th electrode pad 19 that are positioned at first side, and be positioned at the second electrode pad 12, the 4th electrode pad 14, the 6th electrode pad 16, the 8th electrode pad 18, the tenth electrode pad the 20 and the 11 electrode pad 10 of second side.Wherein, the first electrode pad 11 and the second electrode pad 12, the 3rd electrode pad 13 and the 4th electrode pad 14, the 5th electrode pad 15 and the 6th electrode pad 16, the 7th electrode pad 17 and the 8th electrode pad 18 and the 9th electrode pad 19 and the tenth electrode pad 20 are arranged symmetrically relative to the flow direction of fluid.
Wiring layer comprises: be positioned at the heater element 5 in the middle part of underboarding 1, and the first end of heater element 5 is connected to the first electrode pad 11 by contact conductor, and its second end is connected to the second electrode pad 12 by contact conductor, first temperature element to the second temperature element pair, first temperature element is arranged in heater element 5 upstream and downstream to the second temperature element symmetrically to relative to heater element 5, described upstream and downstream with the flow direction of fluid for benchmark, first temperature element is to comprising the first temperature element 7a and the second temperature element 7b, second temperature element is to comprising the 3rd temperature element 8a and the 4th temperature element 8b, and the first end of the first temperature element 7a and the second end are connected to the 9th electrode pad 19 and the tenth electrode pad 20 respectively by contact conductor, the first end of the second temperature element 7b and the second end are connected to the 7th electrode pad 17 and the 8th electrode pad 18 respectively by contact conductor, the first end of the 3rd temperature element 8a and the second end are connected to the 3rd electrode pad 13 and the 4th electrode pad 14 respectively by contact conductor, the first end of the 4th temperature element 8b and the second end are connected to the 5th electrode pad 15 and the 6th electrode pad 16 respectively by contact conductor, and auxiliary temperature element 6, it is positioned at the upstream of diaphragm region 3, and the first end of auxiliary temperature element 6 is connected to the second end of heater element 5, and the second end of auxiliary temperature element 6 is connected to the 11 electrode pad 10 by contact conductor.
The collector of triode 109 is connected with the first outside power supply Vs, and the base stage of triode 109 is connected to the output terminal of amplifier 102, and the emitter of triode 109 is connected to the second electrode pad 12; One end of first fixed resistance 100 is connected to the first electrode pad 11, other end ground connection; One end of second fixed resistance 101 is connected to the 11 electrode pad 10, other end ground connection; The positive input terminal of amplifier 102 is connected between heater element 5 and the first fixed resistance 100, and its negative input end is connected between auxiliary temperature element 6 and the second fixed resistance 101; 9th electrode pad 19 and the 5th electrode pad 15 are connected to outside second source V by contact conductor jointly
ref; Tenth electrode pad 20 is connected with the 3rd electrode pad 13; 4th electrode pad 14 and the 8th electrode pad 18 common ground; 6th electrode pad 16 is connected with the 7th electrode pad 17; The positive input terminal of first instrument amplifier 103 is connected between the first temperature element 7a and the 3rd temperature element 8a, and negative input end is connected between the second temperature element 7b and the 4th temperature element 8b, and its output terminal is as the output terminal of described thermal flow rate sensor.
In above preferred embodiment, heater element 5, first temperature element to (comprising the first temperature element 7a and the second temperature element 7b), the second temperature element to (comprising the 3rd temperature element 8a and the 4th temperature element 8b), and need be symmetrical about fluid flow direction when electrode pad is arranged.Meanwhile, the first temperature element is arranged symmetrically with about heater element 5 with the second temperature element, the heat that heater element 5 can be allowed like this to produce evenly be distributed in heater element 5 both sides.
In above preferred embodiment, the contact conductor live width of heater element 5 is wider than the wiring live width of heater element 5, the resistance value of contact conductor unit length can be reduced like this, thus because of temperature rise that heating current produces on reduction contact conductor, namely the thermal value on lead-in wire electrode can be reduced when heater element 5 is by certain heating current, allow heat can concentrate on heater element 5, be so more conducive to measuring.
In above preferred embodiment, for the first temperature element pair, the first temperature element 7a adopts the mode of parallel routing to be to make the first temperature element 7a identical as far as possible with the thermometric region of the second temperature element 7b with the second temperature element 7b.Same reason can be used for the wire laying mode of explanation the 3rd temperature element 8a and the 4th temperature element 8b.For the first temperature element to the wire laying mode parallel with the second temperature element, in conjunction with corresponding signal processing circuit 111, can effectively improve flow measurement sensitivity and range ability.
In above preferred embodiment, auxiliary temperature element 6 is arranged in the upstream of diaphragm region 3, it is the temperature in order to measure fluid, auxiliary temperature element 6, heater element 5, first fixed resistance 100, second fixed resistance 102, triode 109 and amplifier 102 form heating control circuit 110 (as Fig. 4), be used for realizing heater element 5 and keep certain temperature difference, i.e. constant difference working method with fluid.
In embodiment as Figure 1-Figure 4, be provided with a pair temperature element separately in the both sides of heater element 5.In practice, according to actual needs, can arrange multipair (two to more than) temperature element separately in the both sides of heater element 5, correspondingly, its circuit structure also should correspondingly change.For the situation arranging two pairs of temperature elements separately, its circuit structure and Fig. 8 similar, the like.
Fig. 3 shows according to the thermal flow rate sensor of the present invention's first preferred embodiment diaphragm region Temperature Distribution schematic diagram along the X-X' cross section in Fig. 1.In figure, dotted line 201a represents the Temperature Distribution of the static fluid on cross section, film district 3 of fluid.Heater element 5 heats with the mode convection cell than fluid temperature (F.T.) height Δ Th.The Temperature Distribution of fluid on cross section, diaphragm region 3 when solid line 201b is flow downstream flowing.Owing to producing fluid flowing, the upstream of heater element 5 is caused upstream temperature to decline by fluid cooling, and because fluid flows through heater element 5, downstream is heated, so downstream temperature rises.Therefore, the temperature difference Δ T of heater element 5 upstream and downstream can be measured by first and second temperature element 7a, 7b of being arranged on upstream and third and fourth temperature element 8a, the 8b being arranged on downstream, and then measuring flow.Because first and second temperature element 7a, 7b of upstream adopt parallel wire laying mode, the two thermometric region is identical, same, for third and fourth temperature element 8a, 8b, also has identical effect.Such mode can improve measurement sensistivity after the signal deteching circuit 111 shown in composition graphs 4.
As shown in Figure 4, the flow measurement circuit of thermal flow rate sensor of the present invention comprises heating control circuit 110 and testing circuit 111.
For heating control circuit 110, the series circuit of heater element 5 and the first fixed resistance 100 and the series circuit of temperature element 6 and the second fixed resistance 101 form bridge diagram, get the voltage of the intermediate connection point of above series circuit, be connected with the positive and negative terminal of amplifier 102.The output terminal of amplifier 102 is connected with the base stage of triode 109.The collector of triode is connected with the first power supply Vs, and emitter is connected to the points of common connection of heater element 5 and auxiliary temperature element 6, thus forms the feedback circuit of temperature difference control.By heating control circuit 110, the temperature of heater element 5 can control at certain temperature Δ Th higher than fluid temperature (F.T.).
For testing circuit 111, the series circuit be made up of the first temperature element 7a of upstream and the 3rd temperature element 8a in downstream carries out in parallel with the series circuit be made up of the 4th temperature element 8b in downstream and the second temperature element 7b of upstream, form bridge diagram, the reference voltage of bridge diagram is second source V
ref.The output voltage of bridge diagram is amplified by first instrument amplifier 103.Composition graphs 3 can be known, when the fluid is flowing, third and fourth temperature element 8a, the 8b in first and second temperature element 7a, 7b in upstream and downstream produces temperature difference T, and the balance of above-mentioned two bridge diagrams is changed, to voltage difference be produced, obtain the output signal V corresponding with fluid flow
o.
Fig. 5 to Fig. 8 shows the accompanying drawings of the thermal flow rate sensor according to the present invention's second preferred embodiment.As shown in the figure, underboarding 1' should be comprised based on the thermal flow rate sensor of MEMS technology, the first electric insulation layer 2a' be covered on underboarding 1', the wiring layer be arranged on the first electric insulation layer 2a', the second electric insulation layer 2b' be covered on wiring layer, the first fixed resistance 100', the second fixed resistance 101', amplifier 102', triode 109', first instrument amplifier 103', second instrument amplifier 104' and the 3rd instrument amplifier 105'.
The back side of underboarding 1' is formed with cavity, and the first electric insulation layer 2a' is partly exposed from the back side of underboarding 1', the part that first electric insulation layer 2a', wiring layer and the second electric insulation layer 2b' are positioned on cavity forms diaphragm region 3', underboarding 1' comprises the first electrode pad 21' being positioned at first side, 3rd electrode pad 23', 4th electrode pad 24', 5th electrode pad 25', 6th electrode pad 26', 11 electrode pad 31', 12 electrode pad 32', 13 electrode pad 33' and the 14 electrode pad 34', and be positioned at the second electrode pad 22' of second side, 7th electrode pad 27', 8th electrode pad 28', 9th electrode pad 29', tenth electrode pad 30', 15 electrode pad 35', 16 electrode pad 36', 17 electrode pad 37', 18 electrode pad 38' and the 19 electrode pad 39', wherein, first electrode pad 21' and the second electrode pad 22' arranges symmetrically relative to the flow direction of fluid.
Wiring layer comprises: be positioned at the heater element 5' in the middle part of underboarding 1', and the first end of heater element 5' is connected to the first electrode pad 21' by contact conductor, and its second end is connected to the second electrode pad 22' by contact conductor; first temperature element pair, second temperature element pair, 3rd temperature element to and the 4th temperature element pair, first temperature element pair and the second temperature element pair, 3rd temperature element pair and the 4th temperature element are arranged in heater element 5' upstream and downstream to distributing symmetrically relative to heater element 5', described upstream and downstream with the flow direction of fluid for benchmark, first temperature element is to comprising the first temperature element 7a' and the second temperature element 7b', second temperature element is to comprising the 3rd temperature element 8a' and the 4th temperature element 8b', 3rd temperature element is to comprising the 5th temperature element 9a' and the 6th temperature element 9b', 4th temperature element is to comprising the 7th temperature element 10a' and the 8th temperature element 10b', and first end and second end of the first temperature element 7a' are connected to the 11 electrode pad 31' and the 14 electrode pad 34' respectively by contact conductor, first end and second end of the second temperature element 7b' are connected to the 12 electrode pad 32' and the 13 electrode pad 33' respectively by contact conductor, the first end of the 3rd temperature element 8a' and the second end are connected to the 3rd electrode pad 23' and the 6th electrode pad 26' respectively by contact conductor, the first end of the 4th temperature element 8b' and the second end are connected to the 4th electrode pad 24' and the 5th electrode pad 25' respectively by contact conductor, first end and second end of the 5th temperature element 9a' are connected to the 15 electrode pad 35' and the 18 electrode pad 38' respectively by contact conductor, first end and second end of the 6th temperature element 9b' are connected to the 16 electrode pad 36' and the 17 electrode pad 37' respectively by contact conductor, the first end of the 7th temperature element 10a' and the second end are connected to the 7th electrode pad 27' and the tenth electrode pad 30' respectively by contact conductor, the first end of the 8th temperature element 10b' and the second end are connected to the 8th electrode pad 28' and the 9th electrode pad 29' respectively by contact conductor, and auxiliary temperature element 6', it is positioned at the upstream of diaphragm region 3', and the first end of auxiliary temperature element 6' is connected to second end of heater element 5', and second end of auxiliary temperature element 6' is connected to the 19 electrode pad 39' by contact conductor.
The collector of triode 109' is connected with the first outside power supply Vs', and the base stage of triode 109' is connected to the output terminal of amplifier 102', and the emitter of triode 109' is connected to the second electrode pad 22'; One end of first fixed resistance 100' is connected to the first electrode pad 21', other end ground connection; One end of second fixed resistance 101' is connected to the 19 electrode pad 39', other end ground connection; The positive input terminal of amplifier 102' is connected between heater element 5' and the first fixed resistance 100', and its negative input end is connected between auxiliary temperature element 6' and the second fixed resistance 101'; 11 electrode pad 31' and the 4th electrode pad 24' is connected to outside second source V by contact conductor jointly
ref'; 14 electrode pad 34' is connected with the 3rd electrode pad 23'; 6th electrode pad 26' and the 13 electrode pad 33' common ground, the 5th electrode pad 25' is connected with the 12 electrode pad 32'; The negative input end of first instrument amplifier 103' is connected between the first temperature element 7a' and the 3rd temperature element (8a'), positive input terminal is connected between the second temperature element 7b' and the 4th temperature element 8b', and its output terminal is connected to the negative input end of the 3rd instrument amplifier 105'; 15 electrode pad 35' and the 8th electrode pad 28' is connected to outside second source V jointly
ref'; 18 electrode pad 38' is connected with the 7th electrode pad 27'; Tenth electrode pad 30' and the 17 electrode pad 37' common ground; 9th electrode pad 29' is connected with the 16 electrode pad 36'; The positive input terminal of second instrument amplifier 104' is connected between the 5th temperature element 9a' and the 7th temperature element 10a', negative input end is connected between the 8th temperature element 10b' and the 6th temperature element 9b', and its output terminal is connected to the positive input terminal of the 3rd instrument amplifier 105'; The output terminal of the 3rd instrument amplifier 105' is as the output terminal of described thermal flow rate sensor.
Fig. 7 shows according to the thermal flow rate sensor of the second preferred embodiment of the invention diaphragm region Temperature Distribution schematic diagram along the X-X' cross section in Fig. 5.In figure, dotted line 201a' represents the static Temperature Distribution after 3' cross section, film district of fluid.Heater element 5' heats with the mode convection cell than fluid temperature (F.T.) height Δ Th'.The Temperature Distribution in 3' cross section, diaphragm region when solid line 201b' is flow downstream flowing.Owing to producing fluid flowing, the upstream side of heater element 5' is caused upstream temperature to decline by fluid cooling, and because fluid flows through heater element 5, downstream is heated, so downstream temperature rises.Therefore, can by first and second temperature element 7a', 7b' of upstream, 5th and the 6th temperature element 9a', 9b', third and fourth temperature element 8a', the 8b' in downstream, 7th and the 8th temperature element 10a', 10b' measures the upstream and downstream temperature difference of heater element 5', utilizes the temperature difference Δ T of first and second temperature element 7a', 7b' of upstream and third and fourth temperature element 8a', the 8b' in downstream
1, and the temperature difference Δ T of the 7th and the 8th temperature element 10a', the 10b' in the 5th of upstream the and the 6th temperature element 9a', 9b' and downstream
2and, i.e. Δ T
1+ Δ T
2carry out measuring flow.Because first and second temperature element 7a', 7b' have employed parallel wire laying mode, its thermometric region is identical, same, and six temperature elements for other also have identical effect.Such mode can improve measurement sensistivity and flow measurement range after the signal deteching circuit 111' shown in composition graphs 8.
As shown in Figure 8, flow measurement circuit comprises heating control circuit 110' and testing circuit 111'.
For heating control circuit 110', the series circuit of heater element 5' and fixed resistance 100' and the series circuit of temperature element 6' and fixed resistance 101' form bridge diagram, get the voltage of the intermediate connection point of above series circuit, be connected with the positive and negative terminal of amplifier 102'.The output terminal of amplifier 102' is connected with the base stage of triode 109'.The collector of triode is connected with the first power supply Vs', and emitter is connected to the points of common connection of heater element 5' and auxiliary temperature element 6', thus forms the feedback circuit of temperature difference control.By heating control circuit 110', the temperature of heater element 5' can control at certain temperature Δ Th' higher than fluid temperature (F.T.).
For testing circuit 111', the series circuit be made up of the first temperature element 7a' of upstream and the 3rd temperature element 8a' in downstream carries out in parallel with the series circuit be made up of the 4th temperature element 8b' in downstream and the second temperature element 7b' of upstream, forms the first bridge diagram.Meanwhile, the series circuit be made up of the 5th temperature element 9a' of upstream and the 7th temperature element 10a' in downstream carries out in parallel with the series circuit be made up of the 8th temperature element 10b' in downstream and the 6th temperature element 9b' of upstream, forms the second bridge diagram.The reference voltage of above two bridge diagrams is V
ref'.The output voltage difference of the first bridge diagram and the second bridge diagram is amplified respectively by first and second instrument amplifier 103', 104'.Composition graphs 7 can be known, when the fluid is flowing, third and fourth temperature element 8a', the 8b' in first and second temperature element 7a', 7b' in upstream and downstream produces temperature difference T
1; Similarly, the 7th and the 8th temperature element 10a', the 10b' in the 5th and the 6th temperature element 9a', 9b' in upstream and downstream produces temperature difference T
2, the balance of above-mentioned two bridge diagrams is changed, and will produce voltage difference V respectively
o1and V
o2.By the 3rd instrument amplifier 105', the voltage difference of two bridge diagrams is carried out summation operation, obtain the output signal V corresponding with fluid flow
o'=V
o1+ V
o2.
By comparing the first preferred embodiment and the second preferred embodiment is known, the basis of the sensor construction in a first embodiment of the sensor construction in the second preferred embodiment adds two pairs of temperature elements, namely four pairs of temperature elements are had, and the layout of four pairs of temperature elements on underboarding 1' also there occurs change.Except the layout change of the wiring configuration of each temperature element, the contact conductor relevant to the four pairs of temperature elements, electrode pad, the layout of other element and identical in the first preferred embodiment.This kind of layout is particularly useful for arranging 2 respectively in the upstream and downstream of heater element
n(N is positive integer) situation to heater element.In like manner, based on the difference of temperature element layout, corresponding circuit structure also can change.
In above-mentioned two embodiments, sensor substrate plate can be made up of the material that the pyroconductivity such as silicon, pottery is good.Heater element, temperature element and auxiliary temperature element can be made by the material that temperature-coefficient of electrical resistance is large.Such as, can be formed by the metal material such as the semiconductor material such as polysilicon, monocrystalline silicon, platinum, molybdenum, tungsten, nickel alloy being doped with impurity.Electric insulation layer can by monox (SiO
2), silicon nitride (Si
3n
4) be formed as the film of about a few micron thickness, to obtain good thermal insulation effect.
In addition, as shown in Figure 4 and Figure 8, the instrument amplifier in thermal flow rate sensor of the present invention can arrange fixed resister, to regulate the gain of instrument amplifier.That is, the fixed resister 108 as shown in Figure 4 first instrument amplifier 103 arranged, as shown in Figure 8 on the first to the 3rd instrument amplifier, fixed resister 108', 107', 106' are correspondingly set.
For the first preferred embodiment, the method for making according to thermal flow rate sensor of the present invention is described below.
As depicted in figs. 1 and 2, underboarding 1 is the substrate that single crystal silicon material is made.Surface heat oxidation is carried out to underboarding 1 or is formed the silicon nitride layer of thickness about 1 micron by chemical vapor deposition (CVD) method etc., i.e. the first electric insulation layer 2a.Next, make heater element, temperature element, auxiliary temperature element and contact conductor etc., formed the polycrystalline silicon semiconductor film of thickness about 1 micron by methods such as CVD, then, Impurity Diffusion is carried out to polycrystalline silicon semiconductor film, carries out high-concentration dopant process to become predetermined resistivity.And then, after by photoetching technique photoresist being formed predetermined shape, by methods such as reactive ion etchings, composition is carried out to polycrystalline silicon semiconductor film, obtain heater element 5, temperature element (6,7a, 7b, 8a, 8b), contact conductor.Following again, formed the silicon nitride layer of about 1 micron thickness by CVD etc., i.e. the second electric insulation layer 2b.Then, at the position of contact conductor top electrode pad removing diaphragm 2b, at the material such as position coated with aluminum, gold of electrode pad, the electrode terminal being used for being connected with external circuit is formed.Finally, at the back side of underboarding 1, the mask material of etching is patterned into predetermined shape, utilizes the etching solutions such as potassium hydroxide (KOH) to carry out anisotropic etching, form cavity, thus form diaphragm region 3.
By above operation, the making according to flow sensor of the present invention can be completed.
The effect adopting thermal flow rate sensor according to the present invention to obtain is described below by Fig. 9 ~ Figure 10.
Carry out simulation calculation by the relation between fluid temperature (F.T.) difference-flow velocity (flow) and obtain the curve shown in Fig. 9, curve 301a and curve 301b is respectively temperature difference-flow velocity (flow) relation curve obtained according to the second preferred embodiment and the first preferred embodiment.Simultaneously, obtain the curve shown in Figure 10 by the relation between Fluid Computation measurement sensistivity-flow velocity (flow), curve 401a and curve 401b is respectively sensitivity-flow velocity (flow) relation curve obtained according to the second preferred embodiment and the first preferred embodiment.Can be found out by Fig. 9 ~ Figure 10, two preferred embodiments of the present invention have very high sensitivity in little flow velocity (flow) scope, and along with flow velocity (flow) increases, measurement sensistivity reduces.Meanwhile, compared with the first preferred embodiment, the measurement sensistivity of the second preferred embodiment within the scope of same traffic wants high, and correspondingly flow measurement range is also improved.
In addition, after increasing other auxiliary temperature element by the position of the auxiliary temperature element symmetry in the various embodiments described above, the various embodiments described above also can be used for detecting the flow of detected fluid when following current or adverse current.
In the various embodiments described above, for heater element, be arranged as M word figure, U-shaped figure or Curved (snakelike) and also can be obtained identical effect.Meanwhile, the increase that attenuates of the wiring width of heater element is turned back quantity, can improve the heat generation density of per unit area.
In the various embodiments described above, heater element had both had heating function and had also had temp sensing function, and namely heater element directly utilizes the resistance variations of self to measure the temperature of himself, is then controlled the heating-up temperature of heater element by this temperature information.Same, if arrange that around heater element independently temperature element also can obtain similar effect in the mode detecting temperature of heating elements.
In the various embodiments described above, the differential temperature survey flow of temperature element and the temperature difference mode of flow direction that basis are configured to the upstream and downstream of heater element are illustrated, but according to the heating current of heater element and the mode in resistance change measurement flow and direction, also similar effect can be obtained.
At this, it should be noted that, the content do not described in detail in this instructions, be that those skilled in the art can be realized by the description in this instructions and prior art, therefore do not repeat.
The foregoing is only the preferred embodiments of the present invention, be not used for limiting the scope of the invention.For a person skilled in the art, under the prerequisite not paying creative work, can make some amendments and replacement to the present invention, all such modifications and replacement all should be encompassed within protection scope of the present invention.
Claims (6)
1. the thermal flow rate sensor based on MEMS technology, it is characterized in that, comprise: underboarding (1), the first electric insulation layer (2a) be covered on underboarding (1), the wiring layer be arranged on the first electric insulation layer (2a), the second electric insulation layer (2b) be covered on wiring layer, the first fixed resistance (100), the second fixed resistance (101), amplifier (102), triode (109) and first instrument amplifier (103), wherein
The back side of underboarding (1) is formed with cavity, and the first electric insulation layer (2a) is partly exposed from the back side of underboarding (1), the part that first electric insulation layer (2a), wiring layer and the second electric insulation layer (2b) are positioned on cavity forms diaphragm region (3), underboarding (1) comprises the first electrode pad (11) being positioned at first side, 3rd electrode pad (13), 5th electrode pad (15), 7th electrode pad (17), 9th electrode pad (19), and be positioned at second electrode pad (12) of second side, 4th electrode pad (14), 6th electrode pad (16), 8th electrode pad (18), tenth electrode pad (20) and the 11 electrode pad (10), wherein, first electrode pad (11) and the second electrode pad (12), 3rd electrode pad (13) and the 4th electrode pad (14), 5th electrode pad (15) and the 6th electrode pad (16), 7th electrode pad (17) and the 8th electrode pad (18), and the 9th electrode pad (19) and the tenth electrode pad (20) arrange symmetrically relative to the flow direction of fluid,
Wiring layer comprises: the heater element (5) being positioned at underboarding (1) middle part, and the first end of heater element (5) is connected to the first electrode pad (11) by contact conductor, its second end is connected to the second electrode pad (12) by contact conductor; first temperature element to the second temperature element pair, first temperature element is arranged in heater element (5) upstream and downstream to the second temperature element symmetrically to relative to heater element (5), described upstream and downstream with the flow direction of fluid for benchmark, first temperature element is to comprising the first temperature element (7a) and the second temperature element (7b), second temperature element is to comprising the 3rd temperature element (8a) and the 4th temperature element (8b), and the first end of the first temperature element (7a) and the second end are connected to the 9th electrode pad (19) and the tenth electrode pad (20) respectively by contact conductor, the first end of the second temperature element (7b) and the second end are connected to the 7th electrode pad (17) and the 8th electrode pad (18) respectively by contact conductor, the first end of the 3rd temperature element (8a) and the second end are connected to the 3rd electrode pad (13) and the 4th electrode pad (14) respectively by contact conductor, the first end of the 4th temperature element (8b) and the second end are connected to the 5th electrode pad (15) and the 6th electrode pad (16) respectively by contact conductor, and auxiliary temperature element (6), it is positioned at the upstream of diaphragm region (3), and the first end of auxiliary temperature element (6) is connected to the second end of heater element (5), the second end of auxiliary temperature element (6) is connected to the 11 electrode pad (10) by contact conductor, and each temperature element is formed and the resistance pattern with bending shape parallel by more than two or two,
The collector of triode (109) is connected with outside the first power supply (Vs), the base stage of triode (109) is connected to the output terminal of amplifier (102), and the emitter of triode (109) is connected to the second electrode pad (12); One end of first fixed resistance (100) is connected to the first electrode pad (11), other end ground connection; One end of second fixed resistance (101) is connected to the 11 electrode pad (10), other end ground connection; The positive input terminal of amplifier (102) is connected between heater element (5) and the first fixed resistance (100), and its negative input end is connected between auxiliary temperature element (6) and the second fixed resistance (101); 9th electrode pad (19) and the 5th electrode pad (15) are connected to outside second source (V by contact conductor jointly
ref); Tenth electrode pad (20) is connected with the 3rd electrode pad (13); 4th electrode pad (14) and the 8th electrode pad (18) common ground; 6th electrode pad (16) is connected with the 7th electrode pad (17); The positive input terminal of first instrument amplifier (103) is connected between the first temperature element (7a) and the 3rd temperature element (8a), negative input end is connected between the second temperature element (7b) and the 4th temperature element (8b), and its output terminal is as the output terminal of described thermal flow rate sensor.
2. the thermal flow rate sensor based on MEMS technology, it is characterized in that, comprise underboarding (1'), be covered in the first electric insulation layer (2a') that (1') underboarding is gone up, be arranged in the wiring layer on the first electric insulation layer (2a'), be covered in the second electric insulation layer (2b') on wiring layer, first fixed resistance (100'), second fixed resistance (101'), amplifier (102'), triode (109'), first instrument amplifier (103'), second instrument amplifier (104'), and the 3rd instrument amplifier (105'), wherein,
The underboarding back side is (1') formed with cavity, and the first electric insulation layer (2a') is partly exposed from the underboarding back side (1'), (3') the part that first electric insulation layer (2a'), wiring layer and the second electric insulation layer (2b') are positioned on cavity forms diaphragm region, underboarding (1') on comprise: the first electrode pad (21') being positioned at first side, 3rd electrode pad (23'), 4th electrode pad (24'), 5th electrode pad (25'), 6th electrode pad (26'), 11 electrode pad (31'), 12 electrode pad (32'), 13 electrode pad (33') and the 14 electrode pad (34'), and be positioned at second electrode pad (22') of second side, 7th electrode pad (27'), 8th electrode pad (28'), 9th electrode pad (29'), tenth electrode pad (30'), 15 electrode pad (35'), 16 electrode pad (36'), 17 electrode pad (37'), 18 electrode pad (38') and the 19 electrode pad (39'), wherein, first electrode pad (21') and the second electrode pad (22') are arranged symmetrically relative to the flow direction of fluid,
Wiring layer comprises: be positioned at underboarding (1') middle part heater element (5'), and heater element first end is (5') connected to the first electrode pad (21') by contact conductor, its second end is connected to the second electrode pad (22') by contact conductor; first temperature element pair, second temperature element pair, 3rd temperature element to and the 4th temperature element pair, first temperature element pair and the second temperature element pair, 3rd temperature element pair and the 4th temperature element are to being arranged in heater element upstream and downstream (5') respectively symmetrically, described upstream and downstream with the flow direction of fluid for benchmark, first temperature element is to comprising the first temperature element (7a') and the second temperature element (7b'), second temperature element is to comprising the 3rd temperature element (8a') and the 4th temperature element (8b'), 3rd temperature element is to comprising the 5th temperature element (9a') and the 6th temperature element (9b'), 4th temperature element is to comprising the 7th temperature element (10a') and the 8th temperature element (10b'), and the first end of the first temperature element (7a') and the second end are connected to the 11 electrode pad (31') and the 14 electrode pad (34') respectively by contact conductor, the first end of the second temperature element (7b') and the second end are connected to the 12 electrode pad (32') and the 13 electrode pad (33') respectively by contact conductor, the first end of the 3rd temperature element (8a') and the second end are connected to the 3rd electrode pad (23') and the 6th electrode pad (26') respectively by contact conductor, the first end of the 4th temperature element (8b') and the second end are connected to the 4th electrode pad (24') and the 5th electrode pad (25') respectively by contact conductor, first end and second end of the 5th temperature element (9a') are connected to the 15 electrode pad (35') and the 18 electrode pad (38') respectively by contact conductor, first end and second end of the 6th temperature element (9b') are connected to the 16 electrode pad (36') and the 17 electrode pad (37') respectively by contact conductor, the first end of the 7th temperature element (10a') and the second end are connected to the 7th electrode pad (27') and the tenth electrode pad (30') respectively by contact conductor, the first end of the 8th temperature element (10b') and the second end are connected to the 8th electrode pad (28') and the 9th electrode pad (29') respectively by contact conductor, and auxiliary temperature element (6'), it is positioned at upstream (3'), diaphragm region, and auxiliary temperature element first end is (6') connected to heater element the second end (5'), and auxiliary temperature element the second end is (6') connected to the 19 electrode pad (39') by contact conductor, and each temperature element is formed and the resistance pattern with bending shape parallel by more than two or two,
The collector of triode (109') is connected with outside the first power supply (Vs'), the base stage of triode (109') is connected to the output terminal of amplifier (102'), and the emitter of triode (109') is connected to the second electrode pad (22'); One end of first fixed resistance (100') is connected to the first electrode pad (21'), other end ground connection; One end of second fixed resistance (101') is connected to the 19 electrode pad (39'), other end ground connection; The positive input terminal of amplifier (102') is connected to heater element (5') and between the first fixed resistance (100'), and its negative input end is connected to auxiliary temperature element (6') and between the second fixed resistance (101'); 11 electrode pad (31') and the 4th electrode pad (24') are connected to outside second source (V by contact conductor jointly
ref'); 3rd electrode pad (23') is connected with the 14 electrode pad (34'); 6th electrode pad (26') and the 13 electrode pad (33') common ground; 5th electrode pad (25') is connected with the 12 electrode pad (32'); The negative input end of first instrument amplifier (103') is connected between the first temperature element (7a') and the 3rd temperature element (8a'), positive input terminal is connected between the second temperature element (7b') and the 4th temperature element (8b'), and its output terminal is connected to the negative input end of the 3rd instrument amplifier (105'); 8th electrode pad (28') and the 15 electrode pad (35') are connected to outside second source (V jointly
ref'); 7th electrode pad (27') is connected with the 18 electrode pad (38'); Tenth electrode pad (30') and the 17 electrode pad (37') common ground; 9th electrode pad (29') is connected with the 16 electrode pad (36'); The positive input terminal of second instrument amplifier (104') is connected between the 5th temperature element (9a') and the 7th temperature element (10a'), negative input end is connected between the 8th temperature element (10b') and the 6th temperature element (9b'), and its output terminal is connected to the positive input terminal of the 3rd instrument amplifier (105'); The output terminal of the 3rd instrument amplifier (105') is as the output terminal of described thermal flow rate sensor.
3. the thermal flow rate sensor based on MEMS technology according to claim 1 and 2, it is characterized in that, described heater element is resistance or thermo-sensitive material, and the wiring pattern of described heater element is formed by multiple bending pattern, has the bending part of more than 2.
4. the thermal flow rate sensor based on MEMS technology according to claim 1 and 2, it is characterized in that, the width of the contact conductor of described heater element is wider than the wiring width of described heater element, the wiring area of described heater element and the wiring area of the contact conductor flow direction all about fluid is symmetrical, and is arranged vertically with the flow direction of fluid.
5. the thermal flow rate sensor based on MEMS technology according to claim 1 and 2, is characterized in that, described auxiliary temperature element and all temperature elements can be all resistance or thermo-sensitive material or thermoelectric pile.
6. the thermal flow rate sensor based on MEMS technology according to claim 1 and 2, is characterized in that, described underboarding can be silicon, glass or polymkeric substance.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410742115.8A CN104482971B (en) | 2014-12-05 | 2014-12-05 | A kind of thermal flow rate sensor based on MEMS technology |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410742115.8A CN104482971B (en) | 2014-12-05 | 2014-12-05 | A kind of thermal flow rate sensor based on MEMS technology |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104482971A true CN104482971A (en) | 2015-04-01 |
| CN104482971B CN104482971B (en) | 2019-05-24 |
Family
ID=52757541
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410742115.8A Active CN104482971B (en) | 2014-12-05 | 2014-12-05 | A kind of thermal flow rate sensor based on MEMS technology |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104482971B (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107796456A (en) * | 2017-10-16 | 2018-03-13 | 东南大学 | A kind of wide-range flow sensor and measuring method based on double detection patterns |
| CN109141559A (en) * | 2018-08-29 | 2019-01-04 | 杭州电子科技大学 | A kind of wide range bimodulus thermal sensation bridge-type micro-flowmeter |
| CN109612574A (en) * | 2018-12-04 | 2019-04-12 | 南京粒子声学科技有限公司 | A kind of preparation method of sound particle vibration velocity sensor |
| WO2019242349A1 (en) * | 2018-06-21 | 2019-12-26 | 东南大学 | Ultra-small high-sensitivity two-dimensional anemometer and manufacturing method thereof |
| JP2021100597A (en) * | 2016-08-02 | 2021-07-08 | ベクトン・ディキンソン・アンド・カンパニーＢｅｃｔｏｎ， Ｄｉｃｋｉｎｓｏｎ Ａｎｄ Ｃｏｍｐａｎｙ | System and method for measuring delivered dosage |
| CN113093819A (en) * | 2021-03-30 | 2021-07-09 | 中北大学 | High-precision miniature gas flow controller |
| WO2022244653A1 (en) * | 2021-05-20 | 2022-11-24 | Koa株式会社 | Sensor element |
| WO2023093471A1 (en) * | 2021-11-24 | 2023-06-01 | 华为技术有限公司 | Fluid detection apparatus, microphone, and electronic device |
| WO2023145568A1 (en) * | 2022-01-26 | 2023-08-03 | ミネベアミツミ株式会社 | Fluid sensor |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002168668A (en) * | 2000-11-29 | 2002-06-14 | Yokogawa Electric Corp | Thermal folwmeter |
| CN1896697A (en) * | 2005-07-13 | 2007-01-17 | 株式会社日立制作所 | Gas flow measuring apparatus |
| US20080250855A1 (en) * | 2004-09-28 | 2008-10-16 | Hitachi, Ltd. | Fluid flow sensor and fluid flow measurement device |
| CN103026181A (en) * | 2010-07-30 | 2013-04-03 | 日立汽车系统株式会社 | Thermal flow meter |
| CN103052866A (en) * | 2010-09-30 | 2013-04-17 | 日立汽车系统株式会社 | Thermal flow rate sensor |
| CN103998901A (en) * | 2011-12-07 | 2014-08-20 | 日立汽车系统株式会社 | Airflow measuring apparatus |
-
2014
- 2014-12-05 CN CN201410742115.8A patent/CN104482971B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002168668A (en) * | 2000-11-29 | 2002-06-14 | Yokogawa Electric Corp | Thermal folwmeter |
| US20080250855A1 (en) * | 2004-09-28 | 2008-10-16 | Hitachi, Ltd. | Fluid flow sensor and fluid flow measurement device |
| CN1896697A (en) * | 2005-07-13 | 2007-01-17 | 株式会社日立制作所 | Gas flow measuring apparatus |
| CN103026181A (en) * | 2010-07-30 | 2013-04-03 | 日立汽车系统株式会社 | Thermal flow meter |
| CN103052866A (en) * | 2010-09-30 | 2013-04-17 | 日立汽车系统株式会社 | Thermal flow rate sensor |
| CN103998901A (en) * | 2011-12-07 | 2014-08-20 | 日立汽车系统株式会社 | Airflow measuring apparatus |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2021100597A (en) * | 2016-08-02 | 2021-07-08 | ベクトン・ディキンソン・アンド・カンパニーＢｅｃｔｏｎ， Ｄｉｃｋｉｎｓｏｎ Ａｎｄ Ｃｏｍｐａｎｙ | System and method for measuring delivered dosage |
| CN107796456A (en) * | 2017-10-16 | 2018-03-13 | 东南大学 | A kind of wide-range flow sensor and measuring method based on double detection patterns |
| WO2019242349A1 (en) * | 2018-06-21 | 2019-12-26 | 东南大学 | Ultra-small high-sensitivity two-dimensional anemometer and manufacturing method thereof |
| CN109141559A (en) * | 2018-08-29 | 2019-01-04 | 杭州电子科技大学 | A kind of wide range bimodulus thermal sensation bridge-type micro-flowmeter |
| CN109612574A (en) * | 2018-12-04 | 2019-04-12 | 南京粒子声学科技有限公司 | A kind of preparation method of sound particle vibration velocity sensor |
| CN113093819A (en) * | 2021-03-30 | 2021-07-09 | 中北大学 | High-precision miniature gas flow controller |
| WO2022244653A1 (en) * | 2021-05-20 | 2022-11-24 | Koa株式会社 | Sensor element |
| WO2023093471A1 (en) * | 2021-11-24 | 2023-06-01 | 华为技术有限公司 | Fluid detection apparatus, microphone, and electronic device |
| WO2023145568A1 (en) * | 2022-01-26 | 2023-08-03 | ミネベアミツミ株式会社 | Fluid sensor |
Also Published As
| Publication number | Publication date |
|---|---|
| CN104482971B (en) | 2019-05-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104482971A (en) | Thermal flow sensor on basis of MEMS (micro-electromechanical systems) technology | |
| US6460411B1 (en) | Flow sensor component | |
| EP2233896B1 (en) | Thermal-type flowmeter | |
| EP2600121B1 (en) | Thermal flow meter | |
| US4733559A (en) | Thermal fluid flow sensing method and apparatus for sensing flow over a wide range of flow rates | |
| CN103052866A (en) | Thermal flow rate sensor | |
| JP5656191B2 (en) | Flow rate sensor | |
| CN108254031B (en) | Differential pressure type gas micro-flow sensor and manufacturing method thereof | |
| JPH08166268A (en) | Thermal type flowmeter | |
| CN113933535B (en) | Two-dimensional dual-mode MEMS wind speed and direction sensor and preparation method thereof | |
| Tang et al. | Structure design and optimization of SOI high-temperature pressure sensor chip | |
| CN103076050B (en) | Silicon micro-flow-rate sensor chip in beam film single-beam structure | |
| Kim et al. | A circular-type thermal flow direction sensor free from temperature compensation | |
| JP2005003468A (en) | Flow sensor | |
| CN203479456U (en) | Micro-machined vacuum sensor | |
| CN114199323B (en) | Monolithic integrated MEMS differential pressure flowmeter and preparation method thereof | |
| CN212903385U (en) | Temperature difference type gas flow sensor based on MEMS | |
| CN102564507A (en) | MEMS (micro-electro-mechanical system) quality and flow sensor | |
| CN1936513A (en) | Gas-mass-flow up-down-stream temperature distribution secondary differential measuring method, sensor and flowmeter | |
| CN106595786B (en) | A kind of array cantilever beam diaphragm structure silicon microflow sensor chip | |
| CN103090914B (en) | A kind of four membrane structure silicon microflow sensor chips | |
| RU177514U1 (en) | THERMOANEMOMETRIC FLOW AND GAS FLOW SENSOR | |
| Zhu et al. | Modelling and characterization of a robust, low-power and wide-range thermal wind sensor | |
| CN113466488B (en) | Two-dimensional temperature balance mode MEMS wind speed and direction sensor and preparation method thereof | |
| KR100292799B1 (en) | Micro Flow / Flow Sensors with Membrane Structure, and Flow / Flow Measurement Methods Using Them |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |