CN209387675U - A two-dimensional thermal temperature difference wind speed sensor with environmental self-compensation function - Google Patents

Abstract

A kind of Two-Dimensional Heat temperature difference type air velocity transducer with environment self-compensating function, belongs to air velocity transducer field, solves the problems, such as that the detection rates of existing aluminum-nitride-based hot temperature difference type air velocity transducer are lower.The air velocity transducer: being equipped with heat-conducting medium layer on the substrate of lower thermal conductivity, heating electrode, four temperature sensing electrodes, four slot is thermally isolated and two environment temperature self compensation electrodes are arranged on heat-conducting medium layer.The center of heat-conducting medium layer is arranged in rectangular heating electrode body, and four fan-shaped temperature sensing electrode bodies are separately positioned on the surrounding of heating electrode body, and four are thermally isolated slot and are separately positioned between four temperature sensing electrode bodies and heating electrode body.Two environment temperature self compensation electrode bodies are separately positioned on opposite two edge of heat-conducting medium layer.Each electrode body is respectively provided with there are two extraction electrode, and the external connection end of each extraction electrode is close to the edge of heat-conducting medium layer.

Description

A two-dimensional thermal temperature difference wind speed sensor with environmental self-compensation function

technical field

The utility model relates to a wind speed sensor, in particular to a two-dimensional thermal temperature difference wind speed sensor with an environment self-compensation function.

Background technique

Wind speed sensors are widely used in wind power generation, mine ventilation, solar power generation wind direction control and gas flow monitoring and other fields. In recent years, with the continuous development of MEMS technology, thermal temperature difference wind speed sensors have also made new breakthroughs and developments.

The Chinese invention patent with the authorized announcement number CN 102998479 B discloses a two-dimensional wind speed and direction sensor with an aluminum nitride-based integrated array structure, which belongs to the thermal temperature difference wind speed sensor. The sensor solves the shortcomings of the wind speed sensor integrating the principle of thermal temperature difference using a silicon-based substrate with complex process, high development cost, slow sensor response rate and poor mechanical performance.

However, this aluminum nitride-based thermal temperature difference wind speed sensor uses aluminum nitride ceramic materials with high thermal conductivity as the substrate, which increases its own longitudinal heat conduction loss, resulting in a low detection rate.

Utility model content

The utility model proposes a two-dimensional thermal temperature difference wind speed sensor with an environment self-compensation function to solve the problem of low detection rate of the existing aluminum nitride-based thermal temperature difference wind speed sensor.

The two-dimensional thermal temperature difference wind speed sensor with environmental self-compensation function described in the utility model includes a substrate 1, a heating electrode 2, four temperature detection electrodes 3, four thermal isolation grooves 4 and two ambient temperature self-compensation electrodes 5 ;

The substrate 1 is octagonal and made of low thermal conductivity material. On the top surface of the substrate 1 is laid a thermally conductive medium layer 6, heating electrodes 2, four temperature detection electrodes 3 and two ambient temperature self-compensation electrodes 5 are all arranged on the heat conduction medium layer 6;

The heating electrode 2 includes a heating electrode body 2-1 and two first lead-out electrodes 2-2. The heating electrode body 2-1 has a square coiled spiral structure and is arranged at the center of the heat-conducting medium layer 6. The two first lead-out electrodes 2-2 -2 lead out from the first external end and the second external end of the heating electrode body 2-1 respectively and extend to the edge of the heat conduction medium layer 6;

Each temperature detection electrode 3 includes a temperature detection electrode body 3-1 and two second lead-out electrodes 3-2. The temperature detection electrode body 3-1 includes two serpentine winding structures, and the two serpentine winding structures are Axisymmetrically arranged in a fan-shaped structure, the first external ends of the two serpentine winding structures are interconnected, and the two second lead-out electrodes 3-2 are respectively drawn from the second external ends of the two serpentine winding structures and extend to the heat conduction the edge of the dielectric layer 6;

For the four temperature detection electrodes 3, the small ends of the four temperature detection electrode bodies 3-1 are respectively arranged opposite to the four sides of the heating electrode body 2-1, and the four thermal isolation grooves 4 are respectively arranged on the four temperature detection electrode bodies 3 -1 and the heating electrode body 2-1, the notch of each thermal isolation groove 4 is located on the top surface of the heat conduction medium layer 6, and the bottom of the groove is located in the substrate 1;

Each ambient temperature self-compensating electrode 5 includes an ambient temperature self-compensating electrode body 5-1 and two third lead-out electrodes 5-2. The first outer terminal and the second outer terminal lead out and extend to the edge of the heat-conducting medium layer 6;

For the two ambient temperature self-compensating electrodes 5 , the two ambient temperature self-compensating electrode bodies 5 - 1 are respectively located at two opposite edges of the heat conduction medium layer 6 .

Preferably, the eight sides of the heat-conducting medium layer 6 include four long sides and four short sides, and the short sides and the long sides are arranged alternately and encircled into an octagon;

The end of each lead-out electrode away from the corresponding electrode body is its external terminal;

The outer ends of the two first lead-out electrodes 2-2 of the heating electrode are respectively close to the two opposite long sides of the heat conduction medium layer 6, and the two ambient temperature self-compensating electrode bodies 5-1 are respectively close to the other two sides of the heat conduction medium layer 6. On the long side, the two third lead-out electrodes 5-2 corresponding to each ambient temperature self-compensating electrode body 5-1 are respectively located on both sides of the ambient temperature self-compensating electrode body 5-1, and are connected to the ambient temperature self-compensating electrode body 5-1. The long sides of the side where the main body 5-1 is located are parallel;

The external ends of the two second lead-out electrodes 3-2 of each temperature detection electrode 3 are all located on the same side of the corresponding temperature detection electrode body 3-1, and the external ends of the second lead-out electrodes 3-2 of the four temperature detection electrodes 3 They are respectively close to the four short sides of the heat conduction medium layer 6 .

Preferably, the substrate 1 is made of alumina ceramics, the heat conduction medium layer 6 is realized by an aluminum nitride film, and the heating electrode 2, the four temperature detection electrodes 3 and the two ambient temperature self-compensation electrodes 5 are metal thin film electrodes .

Preferably, the heating electrode 2, the four temperature detecting electrodes 3 and the two ambient temperature self-compensating electrodes 5 are platinum films.

Preferably, the width of each first lead-out electrode 2 - 2 of the heating electrode 2 increases uniformly from the heating electrode body 2 - 1 to the edge of the heat conducting medium layer 6 .

Preferably, the external terminal of each lead-out electrode is a through-hole pad 7 , and the through-hole of the through-hole pad 7 is a round hole, and the through-hole also penetrates the heat-conducting medium layer 6 and the substrate 1 in turn.

Preferably, one end of the lead is drawn from the bottom side of the substrate 1 through the through hole of the through hole pad 7, and is fixedly connected with the through hole pad 7 by platinum paste sintering and welding; after welding, the solidified platinum The paste covers the via pad 7 .

Preferably, the thickness of the substrate 1 is 0.1-0.15mm, the thickness of the heat conduction medium layer 6 is 0.1-10 μm, the thickness of the heating electrode 2, the temperature detection electrode 3 and the ambient temperature self-compensation electrode 5 are all 50-500nm, The line width of the heating electrode body 2-1 is 40-100 μm, the line width of the temperature detection electrode body 3-1 and the ambient temperature self-compensating electrode body 5-1 are both 10-50 μm, and the groove depth of the thermal isolation groove 4 is 0.1- 0.15 mm, the groove width is 20-50 μm, and the hole diameter of the via pad 7 is 50-100 μm.

The environmental self-compensation method of the two-dimensional heat-temperature difference wind speed sensor with environmental self-compensation function described in the utility model includes:

Step 1. Determine the ambient temperature value according to the resistance values of the two ambient temperature self-compensating electrodes 5;

Step 2: Adjust the voltage frequency at both ends of the heating electrode 2 according to the change of the ambient temperature value, so as to keep the temperature field of the wind speed sensor constant.

Preferably, step one determines the ambient temperature value according to the resistance values of the two ambient temperature self-compensating electrodes 5:

When the resistance values of the two ambient temperature self-compensating electrodes 5 are equal, the resistance value of any ambient temperature self-compensating electrode 5 is used as the ambient temperature value;

When the resistance values of the two ambient temperature self-compensating electrodes 5 are not equal, the smaller ambient temperature self-compensating electrode 5 resistance value is taken as the ambient temperature value.

The two-dimensional heat-temperature difference wind speed sensor with environmental self-compensation function described in the utility model has a substrate made of a material with low thermal conductivity, and a heat-conducting medium layer is laid on the top surface of the substrate. This composite substrate with a heat-conducting medium layer is not only conducive to the rapid lateral conduction of temperature but also reduces the longitudinal heat conduction loss, which can effectively improve the thermal response rate of the wind speed sensor, thereby increasing the wind speed and direction detection rate of the wind speed sensor .

Description of drawings

In the following, the two-dimensional thermal temperature difference wind speed sensor with environmental self-compensation function described in the present utility model will be described in more detail based on the embodiments and with reference to the accompanying drawings, wherein:

Fig. 1 is the plane structure schematic diagram of the two-dimensional thermal temperature difference type wind speed sensor with environmental self-compensation function described in the embodiment;

Fig. 2 is the cross-sectional view of the two-dimensional thermal temperature difference wind speed sensor with environmental self-compensation function described in the embodiment;

Fig. 3 is a schematic structural view of the heating electrode described in the embodiment, wherein a is the line width of the heating electrode body;

Fig. 4 is a schematic structural diagram of the temperature detection electrode described in the embodiment, wherein, b is the line width of the temperature detection electrode body;

5 is a schematic structural diagram of the ambient temperature self-compensating electrode described in the embodiment, wherein c is the line width of the ambient temperature self-compensating electrode body.

Detailed ways

The two-dimensional thermal temperature difference wind speed sensor with environmental self-compensation function described in the present utility model will be further described below in conjunction with the accompanying drawings.

Embodiment: The present embodiment will be described in detail below in conjunction with FIG. 1 to FIG. 5 .

The two-dimensional thermal temperature difference air velocity sensor with environmental self-compensation function described in this embodiment includes a substrate 1, a heating electrode 2, four temperature detection electrodes 3, four thermal isolation grooves 4 and two ambient temperature self-compensation electrodes 5 ;

The substrate 1 is octagonal and made of low thermal conductivity material. On the top surface of the substrate 1 is laid a thermally conductive medium layer 6, heating electrodes 2, four temperature detection electrodes 3 and two ambient temperature self-compensation electrodes 5 are all arranged on the heat conduction medium layer 6;

The heating electrode 2 includes a heating electrode body 2-1 and two first lead-out electrodes 2-2. The heating electrode body 2-1 has a square coiled spiral structure and is arranged at the center of the heat-conducting medium layer 6. The two first lead-out electrodes 2-2 -2 lead out from the first external end and the second external end of the heating electrode body 2-1 respectively and extend to the edge of the heat conduction medium layer 6;

Each temperature detection electrode 3 includes a temperature detection electrode body 3-1 and two second lead-out electrodes 3-2. The temperature detection electrode body 3-1 includes two serpentine winding structures, and the two serpentine winding structures are Axisymmetrically arranged in a fan-shaped structure, the first external ends of the two serpentine winding structures are interconnected, and the two second lead-out electrodes 3-2 are respectively drawn from the second external ends of the two serpentine winding structures and extend to the heat conduction the edge of the dielectric layer 6;

For the four temperature detection electrodes 3, the small ends of the four temperature detection electrode bodies 3-1 are respectively arranged opposite to the four sides of the heating electrode body 2-1, and the four thermal isolation grooves 4 are respectively arranged on the four temperature detection electrode bodies 3 -1 and the heating electrode body 2-1, the notch of each thermal isolation groove 4 is located on the top surface of the heat conduction medium layer 6, and the bottom of the groove is located in the substrate 1;

Each ambient temperature self-compensating electrode 5 includes an ambient temperature self-compensating electrode body 5-1 and two third lead-out electrodes 5-2. The first outer terminal and the second outer terminal lead out and extend to the edge of the heat-conducting medium layer 6;

For the two ambient temperature self-compensating electrodes 5 , the two ambient temperature self-compensating electrode bodies 5 - 1 are respectively located at two opposite edges of the heat conduction medium layer 6 .

The eight sides of the heat conduction medium layer 6 in this embodiment include four long sides and four short sides, and the short sides and the long sides are alternately arranged and encircled to form an octagon;

The end of each lead-out electrode away from the corresponding electrode body is its external terminal;

The outer ends of the two first lead-out electrodes 2-2 of the heating electrode are respectively close to the two opposite long sides of the heat conduction medium layer 6, and the two ambient temperature self-compensating electrode bodies 5-1 are respectively close to the other two sides of the heat conduction medium layer 6. On the long side, the two third lead-out electrodes 5-2 corresponding to each ambient temperature self-compensating electrode body 5-1 are respectively located on both sides of the ambient temperature self-compensating electrode body 5-1, and are connected to the ambient temperature self-compensating electrode body 5-1. The long sides of the side where the main body 5-1 is located are parallel;

The external ends of the two second lead-out electrodes 3-2 of each temperature detection electrode 3 are all located on the same side of the corresponding temperature detection electrode body 3-1, and the external ends of the second lead-out electrodes 3-2 of the four temperature detection electrodes 3 They are respectively close to the four short sides of the heat conduction medium layer 6 .

The substrate 1 of this embodiment is made of alumina ceramics with a purity of 99%, the heat conduction medium layer 6 is realized by an aluminum nitride film, and the heating electrode 2, four temperature detection electrodes 3 and two ambient temperature self-compensation electrodes 5 are all for metal thin film electrodes.

In this embodiment, the heating electrode 2 , the four temperature detecting electrodes 3 and the two ambient temperature self-compensating electrodes 5 are all platinum films.

The width of each first lead-out electrode 2 - 2 of the heater electrode 2 in this embodiment increases uniformly from the heater electrode body 2 - 1 to the edge of the heat conduction medium layer 6 .

The external terminal of each lead-out electrode in this embodiment is a through-hole pad 7 , and the through hole of the through-hole pad 7 is a round hole, and the through hole also penetrates the heat-conducting medium layer 6 and the substrate 1 in turn.

One end of the lead is drawn from the bottom side of the substrate 1 through the through hole of the through hole pad 7, and is fixedly connected to the through hole pad 7 by platinum paste sintering and welding; after welding, the solidified platinum paste covers the through hole solder Disk 7.

The thickness of the substrate 1 in this embodiment is 0.1-0.15mm, the thickness of the heat-conducting medium layer 6 is 0.1-10 μm, the thickness of the heating electrode 2, the temperature detection electrode 3 and the ambient temperature self-compensation electrode 5 are all 50-500nm, heating The line width of the electrode body 2-1 is 40-100 μm, the line width of the temperature detection electrode body 3-1 and the ambient temperature self-compensating electrode body 5-1 are both 10-50 μm, and the groove depth of the thermal isolation groove 4 is 0.1-0.15 mm, the groove width is 20-50 μm, and the hole diameter of the via pad 7 is 50-100 μm.

The two-dimensional thermal temperature difference wind speed sensor with environmental self-compensation function described in this embodiment also has the following beneficial effects:

1. The heating electrode body 2-1 has a square coiled spiral structure, forming a square temperature field at the center of the wind speed sensor, which is conducive to the diffusion of temperature to the surroundings. The temperature detection electrode body 3-1 distributed around the heating electrode body 2-1 forms a fan-shaped temperature diffusion field, which is conducive to the formation of a symmetrical temperature field. The width of each first extraction electrode 2-2 of the heating electrode 2 increases uniformly from the heating electrode body 2-1 to the edge of the heat conduction medium layer 6, which reduces the influence of the first extraction electrode 2-2 on the temperature field.

2. The four fan-shaped areas formed by the four temperature detection electrode bodies 3-1 just cover the four temperature diffusion fields of the heating electrode body 2-1, which is conducive to improving the exchange area and efficiency of the heat field, and improving the sensitivity and detection accuracy of wind speed and direction.

3. One end of the lead is drawn from the bottom side of the substrate 1 through the through hole of the through hole pad 7, and is fixedly connected to the through hole pad 7 by sintering and welding with platinum paste; after welding, the solidified platinum paste covers the through hole pad 7. Hole Pad 7. This welding method not only plays the role of welding the lead wire but also fixes the lead wire, which improves the reliability. At the same time, the surface of the wind speed sensor has no distribution of lead wires and welding reinforcement protrusions, which reduces the influence on the airflow and reduces the problem of sealing interference.

The wind speed and wind direction detection principle of the two-dimensional heat-temperature difference wind speed sensor with environmental self-compensation function described in this embodiment is a prior art, and will not be repeated here.

The preparation process of the two-dimensional thermal temperature difference wind speed sensor with environmental self-compensation function described in this embodiment is as follows:

Step 1: cleaning and baking the alumina ceramic substrate;

Step 2: sputtering an aluminum nitride heat conduction medium film on the alumina ceramic substrate baked in step 1;

Step 3: nitriding or oxidizing the alumina ceramic substrate on which the aluminum nitride heat-conducting dielectric film was sputtered in step 2;

Step 4: Forming a layer of positive photoresist on the step 3 nitriding or oxidizing nitriding or aluminum oxynitriding heat conducting medium film;

Step 5: Make a plate-making mold, the plate-making mold is a reticle of the opposite pattern of the sensor electrode surface structure formed by the heating electrode 2, four temperature detection electrodes 3 and two ambient temperature self-compensating electrodes 5, and use the plate-making mold to step 4 Perform reverse exposure and development on the formed positive photoresist to obtain an alumina ceramic substrate with a photoresist pattern;

Step 6: Metallize the alumina ceramic substrate with the photoresist pattern in step 5 to form an alumina ceramic substrate with a platinum film pattern;

Step 7: The aluminum oxide ceramic substrate with the platinum film pattern covered in step 6 is subjected to flexible mechanical peeling, and the platinum film sensor with the opposite pattern to the pattern of the plate-making mold is left on the surface of the aluminum nitride dielectric film on the alumina ceramic substrate Electrode pattern structure;

Step 8: Carry out laser etching on the alumina ceramic substrate at the periphery of the heating electrode body 2-1 and the center of the through-hole pad 7 in the platinum film sensor electrode pattern structure in step 7, and etch to form thermal isolation grooves 4 and via via pad 7;

Step 9: The platinum wire leads pass through the through hole of the pad from the lead-out pad, and the platinum wire lead is drawn out on the back of the alumina ceramic substrate, and the pad on the front of the alumina ceramic substrate is covered with platinum paste solder and a protective layer. After curing, The two-dimensional thermal temperature difference wind speed sensor has been manufactured.

For the alumina ceramic substrate baked in step 1, use the magnetron radio frequency sputtering method to sputter the aluminum nitride film in the ratio of argon to nitrogen at 2:1 and maintain a pressure of 0.5-1.2Pa to obtain nitrided Aluminum heat conduction medium film.

In step 2, the aluminum nitride film is sputtered by radio frequency sputtering in an environment of 2:1 ratio of argon gas and nitrogen gas to maintain a pressure of 0.5-1.2 Pa. The radio frequency sputtering process:

The sputtering temperature is alternately carried out at room temperature 25°C and 200°C, that is, magnetron radio frequency sputtering aluminum nitride film at room temperature 25°C for 2 hours, heating to 200°C, then radio frequency sputtering aluminum nitride film for 2 hours, and cooling down to room temperature 25°C , during radio frequency sputtering aluminum nitride thin film coating;

By repeating the above radio frequency sputtering process 2-3 times, a multilayer aluminum nitride film with obvious grain boundaries can be obtained.

The environmental self-compensation method of the two-dimensional thermal temperature difference wind speed sensor with environmental self-compensation function described in this embodiment includes:

Step 1. Determine the ambient temperature value according to the resistance values of the two ambient temperature self-compensating electrodes 5;

Step 2: Adjust the voltage frequency at both ends of the heating electrode 2 according to the change of the ambient temperature value, so as to keep the temperature field of the wind speed sensor constant.

Step 1. The specific method of determining the ambient temperature value according to the resistance values of the two ambient temperature self-compensating electrodes 5 is as follows:

When the resistance values of the two ambient temperature self-compensating electrodes 5 are equal, the resistance value of any ambient temperature self-compensating electrode 5 is used as the ambient temperature value;

When the resistance values of the two ambient temperature self-compensating electrodes 5 are not equal, the smaller ambient temperature self-compensating electrode 5 resistance value is taken as the ambient temperature value.

When there is no air flow on the surface of the wind speed sensor, the resistance values of the two ambient temperature self-compensating electrodes 5 are equal and unchanged. At this time, the resistance value of any ambient temperature self-compensating electrode 5 is taken as the ambient temperature value. When the ambient temperature changes or the radial direction of the external airflow is perpendicular to the direction of the two ambient temperature self-compensating electrodes 5, the resistance values of the two ambient temperature self-compensating electrodes 5 change at the same time, but are still equal. At this time, any ambient temperature self-compensating The resistance value of the electrode 5 was taken as the ambient temperature value. When the resistance values of the two ambient temperature self-compensating electrodes 5 are not equal, it means that the direction of the external airflow forms a certain angle with the radial direction of the two ambient temperature self-compensating electrodes 5, and the side with the smaller resistance value is the airflow input direction. When using the smaller ambient temperature, the resistance value of the self-compensating electrode 5 is taken as the ambient temperature value.

The voltage frequency at both ends of the heating electrode 2 is determined by the ambient temperature value. Specifically, the influence of the ambient temperature change on the wind speed and direction error is calibrated through the ambient temperature experiment, and the relationship curve between the ambient temperature and the wind speed and wind direction can be obtained, so that the wind speed self-compensation function can be realized and the wind speed can be improved. and wind direction detection accuracy.

Although the invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely illustrative of the principles and applications of the invention. It is therefore to be understood that numerous modifications may be made to the exemplary embodiments and that other arrangements may be devised without departing from the spirit and scope of the invention as defined by the appended claims. It shall be understood that different dependent claims and features described herein may be combined in a different way than that described in the original claims. It will also be appreciated that features described in connection with individual embodiments can be used in other described embodiments.

Claims (8)

1. A two-dimensional thermal temperature difference type wind speed sensor with environmental self-compensation function, it is characterized in that, described wind speed sensor comprises substrate (1), heating electrode (2), four temperature detecting electrodes (3), four Thermal isolation tank (4) and two ambient temperature self-compensating electrodes (5); The substrate (1) is octagonal and made of low thermal conductivity material, and a thermally conductive medium layer (6) is laid on the top surface of the substrate (1), heating electrodes (2), four temperature detection electrodes (3 ) and two ambient temperature self-compensating electrodes (5) are all arranged on the heat conduction medium layer (6); The heating electrode (2) includes a heating electrode body (2-1) and two first lead-out electrodes (2-2). The heating electrode body (2-1) has a square coiled spiral structure and is arranged on the bottom of the heat conduction medium layer (6). In the central position, the two first lead-out electrodes (2-2) are respectively led out from the first outer connection end and the second outer connection end of the heating electrode body (2-1) and extend to the edge of the heat-conducting medium layer (6); Each temperature detection electrode (3) includes a temperature detection electrode body (3-1) and two second lead-out electrodes (3-2), and the temperature detection electrode body (3-1) includes two serpentine winding structures, The two serpentine winding structures are arranged axially symmetrically to form a fan-shaped structure, the first external ends of the two serpentine winding structures are interconnected, and the two second lead-out electrodes (3-2) are connected to each other from the two serpentine winding structures respectively. The second external end of the lead out and extend to the edge of the heat conduction medium layer (6); For the four temperature detection electrodes (3), the small ends of the four temperature detection electrode bodies (3-1) are respectively set opposite to the four sides of the heating electrode body (2-1), and the four thermal isolation grooves (4) are respectively set Between the four temperature detection electrode bodies (3-1) and the heating electrode body (2-1), the notch of each thermal isolation groove (4) is located on the top surface of the heat conduction medium layer (6), and the bottom of the groove is are all located in the substrate (1); Each ambient temperature self-compensating electrode (5) includes an ambient temperature self-compensating electrode body (5-1) and two third lead-out electrodes (5-2), and the two third lead-out electrodes (5-2) lead out from the first external end and the second external end of the compensation electrode body (5-1) and extend to the edge of the heat conduction medium layer (6); For the two ambient temperature self-compensating electrodes (5), the two ambient temperature self-compensating electrode bodies (5-1) are respectively located at two opposite edges of the heat conduction medium layer (6). 2. The two-dimensional heat temperature difference type wind speed sensor with environmental self-compensation function as claimed in claim 1, is characterized in that, the eight sides of heat conduction medium layer (6) comprise four long sides and four short sides, short side and long side Arranged alternately and encircled into an octagon; The end of each lead-out electrode away from the corresponding electrode body is its external terminal; The outer ends of the two first lead-out electrodes (2-2) of the heating electrode are respectively close to the two opposite long sides of the heat conduction medium layer (6), and the two ambient temperature self-compensating electrode bodies (5-1) are respectively close to the heat conduction medium On the other two long sides of the layer (6), two third lead-out electrodes (5-2) corresponding to each ambient temperature self-compensating electrode body (5-1) are respectively located in the ambient temperature self-compensating electrode body (5-1) ), and are all parallel to the long side of the side where the ambient temperature self-compensating electrode body (5-1) is located; The external ends of the two second lead-out electrodes (3-2) of each temperature detection electrode (3) are all located on the same side of the corresponding temperature detection electrode body (3-1), and the second of the four temperature detection electrodes (3) The external ends of the lead-out electrodes (3-2) are respectively close to the four short sides of the heat-conducting medium layer (6). 3. The two-dimensional thermal temperature difference type wind speed sensor with environmental self-compensation function as claimed in claim 2, characterized in that, the substrate (1) is made of alumina ceramics, and the heat-conducting medium layer (6) adopts aluminum nitride film Realized, the heating electrode (2), the four temperature detection electrodes (3) and the two ambient temperature self-compensation electrodes (5) are all metal thin film electrodes. 4. the two-dimensional thermal temperature difference type wind speed sensor with environmental self-compensation function as claimed in claim 3, is characterized in that, heating electrode (2), four temperature detection electrodes (3) and two ambient temperature self-compensation electrodes ( 5) Both are platinum film. 5. The two-dimensional thermal temperature difference type wind speed sensor with environmental self-compensation function as claimed in claim 4, characterized in that, the width of each first lead-out electrode (2-2) of the heating electrode (2) is from the heating electrode body (2-1) uniformly increases to the edge direction of the heat conduction medium layer (6). 6. the two-dimensional thermal temperature difference type wind speed sensor with environmental self-compensation function as claimed in claim 5, is characterized in that, the external terminal of each lead-out electrode is a through-hole pad (7), and the through-hole pad (7) ) is a circular hole, and the through hole also runs through the heat-conducting medium layer (6) and the substrate (1) in sequence. 7. The two-dimensional thermal temperature difference type wind speed sensor with environmental self-compensation function as claimed in claim 6, is characterized in that, one end of the lead wire is connected from the bottom side of the substrate (1) through the through-hole pad (7). The hole is drawn out, and is fixedly connected with the through-hole pad (7) by means of platinum paste sintering and welding; after welding, the solidified platinum paste covers the through-hole pad (7). 8. The two-dimensional thermal temperature difference wind speed sensor with environmental self-compensation function as claimed in claim 7, characterized in that, the thickness of the substrate (1) is 0.1-0.15mm, and the thickness of the heat-conducting medium layer (6) is 0.1mm. -10μm, the thickness of the heating electrode (2), the temperature detection electrode (3) and the ambient temperature self-compensation electrode (5) are all 50-500nm, the line width of the heating electrode body (2-1) is 40-100μm, the temperature detection The line width of the electrode body (3-1) and the ambient temperature self-compensating electrode body (5-1) are both 10-50 μm, the groove depth of the thermal isolation groove (4) is 0.1-0.15 mm, and the groove width is 20-50 μm, The hole diameter of the through-hole pad (7) is 50-100 μm.