Micro-heater with local surface super-high temperature uniformity

Abstract

The present application relates to the field of micro-heater, and particularly relates to a micro-heater with local surface super-high temperature uniformity, comprising a substrate (1), a serpentine heating resistance wire (2) and a lead pin (3); the serpentine heating resistance wire (2) is folded and arranged in the same length along the width direction of the substrate (1) and is folded and arranged in equal intervals along the length direction of the substrate (1); the resistance value changes along the length direction of the substrate (1) according to a weight function changing along the length direction of the substrate (1), so that the serpentine heating resistance wire (2) has the minimum width and / or thickness near the edge of the substrate (1) and has the maximum width and / or thickness at the corresponding position of the center of the substrate (1). The micro-heater provided by the present application is weighted designed for the serpentine heating resistance wire (2), and the local surface super-high temperature uniformity micro-heater design is realized by compensating the heat loss at the edge of the substrate.

Description

Technical Field

[0001] This invention relates to the field of microheaters, and particularly to a microheater with localized ultra-high surface temperature uniformity. Background Technology

[0002] Gas sensors, composed of microheaters and sensing elements, are widely used in industrial, consumer, and environmental monitoring applications. In gas sensors, a large, uniformly heated area facilitates the reaction of the gas with the catalyst within the appropriate temperature range, improving the device's sensitivity and selectivity. Furthermore, a uniform temperature distribution results in higher heating efficiency.

[0003] Typically, the serpentine heating resistance wire 2 heats the substrate 1. Since the interior of the substrate 1 only experiences heat loss from the surrounding air and radiation, while the periphery of the substrate 1 experiences additional heat loss from its sides, the edges of the substrate 1 surface are cooler than the interior, resulting in an uneven temperature distribution. Placing the substrate 1 on a material with high thermal conductivity can achieve temperature uniformity, but this also introduces more heat loss, increasing the power consumption of the microheater. One method to address the temperature uniformity issue in microheaters is to design serpentine heating resistance wires 2 with different patterns. For example, Wu Lei of the Shanghai Institute of Microsystem and Information Technology (Structural Design and Fabrication of MEMS Planar Microheaters, 2005) used magnetron sputtering to sputter six different patterns of serpentine heating resistance wires 2, designing a 0.5mm × 0.3mm active region on a 1mm × 1mm thin film surface, achieving a temperature gradient of 0.05K / µm within the active region.

[0004] However, there is still a large temperature variation in the entire active region of the MEMS surface micro heater. The main reason is that the heating resistance wires of each pattern designed in the paper have the same resistance width in the active region, and the problem of compensating for the temperature non-uniformity in the active region by the uniform heat source distribution generated by the heating resistance wire is not considered. Summary of the Invention

[0005] The purpose of this invention is to overcome the uneven surface temperature distribution of existing microheaters by weighting the serpentine heating resistance wire 2 and compensating for heat loss at the boundary of the substrate 1 to achieve microheater design with ultra-high local surface temperature uniformity, so as to meet the design requirements of high precision, high sensitivity and good selectivity of gas sensors.

[0006] To achieve the aforementioned objective, the present invention provides a microheater with ultra-high temperature and localized surface uniformity, comprising: a substrate 1, a serpentine heating resistance wire 2, and lead pins 3 connecting the serpentine heating resistance wire 2; characterized in that the serpentine heating resistance wire 2 is placed at the center of the upper or lower surface of the substrate 1; the lead pins 3 are symmetrically deposited on both sides of the serpentine heating resistance wire 2 along the length direction of the substrate 1, and are electrically connected to the serpentine heating resistance wire 2 and external components; wherein...

[0007] The serpentine heating resistance wires 2 are folded and arranged in a manner of equal length in the width direction of the substrate 1, and folded and arranged at equal intervals in the length direction of the substrate 1; wherein,

[0008] The resistance value of the serpentine heating resistance wire 2 varies along the length direction of the substrate 1 according to a weighted function that varies along the length direction of the substrate 1. This includes: changing the thickness and / or width of the serpentine heating resistance wire 2 along the length direction of the substrate 1 according to the weighted function to change the resistance value of the serpentine heating resistance wire 2, so that the serpentine heating resistance wire 2 has the minimum width and / or thickness near the edge of the substrate 1, and the maximum width and / or thickness at the corresponding position at the center of the substrate 1. The width and / or thickness of the serpentine heating resistance wire 2 gradually increases and then decreases along the length direction of the substrate 1, and has the maximum width or thickness at the center of the surface of the substrate 1. The way the width and / or thickness changes is based on a weighted function that varies along the length direction of the substrate 1.

[0009] As an improvement to the above-mentioned device, the weighting function includes: a cosine function, a quadratic function, a trigonometric wave function, a Gaussian function, or a Sinc function.

[0010] As an improvement to the above-mentioned device, the weights of the weighting function vary between 1 and 10.

[0011] As an improvement to the above-mentioned device, the width of the serpentine heating resistance wire 2 is independently weighted along the length direction of the substrate 1 according to the weighting function, or the thickness of the serpentine heating resistance wire 2 is independently weighted along the length direction of the substrate 1 according to the weighting function, or the thickness and width of the serpentine heating resistance wire 2 are simultaneously weighted together along the length direction of the substrate 1 according to the weighting function.

[0012] As an improvement to the above-mentioned device, a single serpentine heating resistance wire 2 or multiple serpentine heating resistance wires 2 are disposed at the bottom of the substrate 1, wherein multiple serpentine heating resistance wires are deposited side by side on the surface of the substrate 1 along the width direction of the substrate 1.

[0013] As an improvement to the above-mentioned device, the material of the serpentine heating resistance wire 2 includes: metallic materials, such as gold, platinum, aluminum or copper; composite metallic materials, such as cadmium-platinum or aluminum-cadmium-platinum composite metallic materials; semiconductor materials, such as silicon carbide; and the width and thickness of the serpentine heating resistance wire 2 are in the nanometer to micrometer range.

[0014] As an improvement to the above-mentioned device, the serpentine heating resistance wire 2 is deposited on the surface of the substrate 1 using a surface deposition method; the surface deposition method includes physical vapor deposition or chemical vapor deposition.

[0015] As an improvement to the above-mentioned device, the lead pin 3 includes: a metal pin, such as aluminum, copper, platinum or gold; and also includes: a composite film metal pin, such as a cadmium-platinum composite metal pin, wherein the lead pin 3 is deposited on the surface of the substrate 1 using a surface deposition process.

[0016] As an improvement to the above-mentioned device, the material of the substrate 1 includes: piezoelectric material, semiconductor material or polymer material, such as: lithium niobate, quartz, lithium tantalate, lanthanum gallium silicate, ceramic, silicon, diamond or silicon nitride.

[0017] The advantage of this invention is that it places a serpentine heating resistance wire 2 and lead pins 3 on the surface of the substrate 1, and uses a weighting function to independently or in combination weight the thickness and / or width of the serpentine heating resistance along the length of the substrate 1, so that the micro heater has the characteristic of local surface ultra-high temperature uniformity, which is beneficial to improving the selectivity, sensitivity and response of the gas sensor. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the microheater;

[0019] Figure 2 This is a front view of the micro heater;

[0020] Figure 3 This is a schematic diagram of the structure of each part of the microheater;

[0021] Figure 4 A serpentine heating resistance wire for a microheater, with width weighting;

[0022] Figure 5 The surface structure of the microheater is one;

[0023] Figure 6 The second surface structure of the microheater;

[0024] Figure 7 This is a schematic diagram of the surface temperature distribution of the microheater;

[0025] Figure 8This is a schematic diagram of the surface temperature gradient of the microheater.

[0026] Figure 9 The width and height of a serpentine heating resistance wire 2 are weighted for a micro heater.

[0027] Attached Figure Labels

[0028] 1. Piezoelectric material; 2. Serpentine heating resistance wire; 3. Lead pins Detailed Implementation

[0029] The technical solutions provided by the present invention will be further illustrated below with reference to the embodiments.

[0030] like Figure 1 As shown, the present invention proposes a micro heater with localized ultra-high surface temperature uniformity. The micro heater includes a substrate 1, a serpentine heating resistance wire 2, and lead pins 3. The serpentine heating resistance wire 2 is placed on the surface of the substrate 1, and the lead pins 3 are placed on the surface of the substrate 1. The serpentine heating resistance wire 2 is folded and extended at equal intervals along the length direction of the substrate 1, while the length of the substrate 1 remains unchanged in the width direction. The width and / or thickness of the serpentine heating resistance wire 2 along the length direction of the substrate 1 are independently or in combination weighted to achieve temperature uniformity design on the surface of the substrate 1.

[0031] Specifically, the microheater with ultra-high temperature and localized surface uniformity provided by the present invention includes: a substrate 1, a serpentine heating resistance wire 2, and lead pins 3 connected to the serpentine heating resistance wire 2; characterized in that the serpentine heating resistance wire 2 is placed at the center of the upper or lower surface of the substrate 1; the lead pins 3 are symmetrically deposited on both sides of the serpentine heating resistance wire 2 along the length direction of the substrate 1, and are electrically connected to the serpentine heating resistance wire 2 and the outside; wherein,

[0032] The serpentine heating resistance wires 2 are folded and arranged in a manner of equal length in the width direction of the substrate 1, and folded and arranged at equal intervals in the length direction of the substrate 1; wherein,

[0033] The resistance value of the serpentine heating resistance wire 2 varies along the length direction of the substrate 1 according to a weighted function that varies along the length direction of the substrate 1. This includes: changing the thickness and / or width of the serpentine heating resistance wire 2 along the length direction of the substrate 1 according to the weighted function to change the resistance value of the serpentine heating resistance wire 2; so that the serpentine heating resistance wire 2 has the minimum width and / or thickness near the edge of the substrate 1, and the maximum width and / or thickness at the corresponding position at the center of the substrate 1. The width and / or thickness of the serpentine heating resistance wire 2 gradually increases and then decreases along the length direction of the substrate 1, and has the maximum width or thickness at the center of the surface of the substrate 1. The variation of the width and / or thickness is based on a weighted function that varies along the length direction of the substrate 1.

[0034] The weighting function includes: cosine function, quadratic function, trigonometric wave function, Gaussian function or Sinc function.

[0035] The weights of the weighting function vary between 1 and 10.

[0036] The serpentine heating resistance wire 2 is independently weighted along the length direction of the substrate 1 according to the weight function, or the serpentine heating resistance wire 2 is independently weighted along the length direction of the substrate 1 according to the weight function, or the serpentine heating resistance wire 2 is simultaneously weighted along the length direction of the substrate 1 according to the weight function, combining the weight of the thickness and width of the serpentine heating resistance wire 2.

[0037] The bottom of the substrate 1 is provided with a single serpentine heating resistance wire 2 or multiple serpentine heating resistance wires 2, wherein multiple serpentine heating resistance wires are deposited side by side on the surface of the substrate 1 along the width direction of the substrate 1.

[0038] The materials of the serpentine heating resistance wire 2 include: metallic materials, such as gold, platinum, aluminum or copper; composite film materials, such as cadmium-platinum composite metal materials or aluminum-cadmium-platinum composite metal materials; semiconductor materials, such as silicon carbide; the width and thickness of the serpentine heating resistance wire 2 are in the nanometer to micrometer range.

[0039] The serpentine heating resistance wire 2 is deposited on the surface of the substrate 1 using a surface deposition method; the surface deposition method includes physical vapor deposition or chemical vapor deposition.

[0040] The lead pin 3 includes: metal pins, such as aluminum, copper, platinum or gold; and also includes: composite film metal pins, such as cadmium-platinum composite metal pins, wherein the lead pins are deposited on the surface of the substrate 1 using a surface deposition process.

[0041] The substrate 1 is made of piezoelectric materials, semiconductor materials, or polymer materials, such as lithium niobate, quartz, lithium tantalate, lanthanum gallium silicate, ceramics, silicon, diamond, or silicon nitride.

[0042] To gain a more comprehensive understanding of the present invention, and to reveal its other objectives and advantages, the present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0043] Example 1:

[0044] like Figure 1 As shown, in Example 1, substrate 1 is a 128° Y-cut lithium niobate crystal 1, on which aluminum 2 and lead pins 3 are deposited. Lead pins 3 are made by depositing a layer of gold on the aluminum surface. The lithium niobate is 6 mm long, 3 mm wide, and 250 μm thick. For detailed device composition, refer to [reference needed]. Figure 3 A serpentine heating resistance wire 2 is deposited in the middle of the device surface, and lead pins 3 are designed at the edges. Surface weighted resistance reference. Figure 4 The thin aluminum metal film is arranged in a basic serpentine structure, weighting the resistance width. The resistance width is smaller at the edges and larger in the center, exhibiting a quadratic function distribution with the x-direction opening downwards. The resistance width ranges from 2µm to 40µm, the resistance thickness is 2µm, and the resistance length is approximately 23cm. For connecting the weighted resistance wire to lead pin 3, refer to... Figure 5 Quadrilateral lead pins 3 are deposited on both sides of the weighted resistance wire to achieve electrical connection points to the outside world. The results from the numerical simulation are referenced below. Figure 7 It can be seen that the middle part of the surface has extremely high temperature uniformity, and the temperature gradient reference... Figure 8 It can be seen that a temperature gradient of <0.0005K / um and a temperature difference of <0.1K can be achieved within a surface thickness of 1.8mm to 4.2mm.

[0045] Implementation Case 2

[0046] As shown in Figure 1, the substrate 1 is a 128° Y-cut lithium niobate crystal 1 on which aluminum 2 and lead pins 3 are deposited. The lead pins 3 are made by depositing a layer of gold on the aluminum surface. The lithium niobate is 6 mm long, 3 mm wide, and 250 μm thick. For detailed device composition, please refer to [reference needed]. Figure 3 A heating resistor is deposited in the center of the device surface, with lead pins 3 designed at the edges. Surface weighted resistance reference. Figure 4 The thin aluminum metal film is arranged in a basic serpentine structure, weighting the resistance width. The resistance width is smaller at the edges and larger in the center, exhibiting a quadratic function distribution with the x-direction opening downwards. The resistance width varies from 2µm to 40µm, the resistance thickness is 2µm, and the resistance length is approximately 23cm. The weighted resistance wire 2 is connected to the lead pin 3, as shown in the reference diagram. Figure 6 Quadrilateral lead pins 3 are deposited on both sides of the weighted resistance wire to establish electrical connection points to the outside world, while blank pins are left to increase the connection stability of the device. The results in the numerical simulation are referenced below. Figure 7 It can be seen that the middle part of the surface has extremely high temperature uniformity, and the temperature gradient reference... Figure 8 It can be seen that a temperature gradient of <0.0005K / um and a temperature difference of <0.1K can be achieved within a surface thickness of 1.8mm to 4.2mm.

[0047] Implementation Case 3

[0048] As shown in Figure 1, the substrate 1 is a 128° Y-cut lithium niobate crystal 1 on which aluminum 2 and lead pins 3 are deposited. The lead pins 3 are made by depositing a layer of gold on the aluminum surface. The lithium niobate is 6 mm long, 3 mm wide, and 250 μm thick. For detailed device composition, please refer to [reference needed]. Figure 3 A heating resistor is deposited in the center of the device surface, with lead pins 3 designed at the edges. Surface-weighted resistance wire reference. Figure 2 The aluminum thin film 2 is arranged in a basic serpentine structure, weighting the resistance thickness. The resistance thickness is thinner at the edges and thicker in the center, with the thickness distributed as a quadratic function opening downwards along the y-direction. The resistance thickness varies from 2µm to 40µm, with a width of 2µm and a length of approximately 23cm. The weighted resistance wire 2 is connected to the lead pin 3, as shown in the reference diagram. Figure 6 Quadrilateral lead pins 3 are deposited on both sides of the weighted resistance wire to establish electrical connection points to the outside world, while blank pins are left to increase the connection stability of the device. The results in the numerical simulation are referenced below. Figure 7 It can be seen that the middle part of the surface has extremely high temperature uniformity, and the temperature gradient reference... Figure 8 It can be seen that a temperature gradient of <0.0005K / um and a temperature difference of <0.1K can be achieved within a surface thickness of 1.8mm to 4.2mm.

[0049] Implementation Case 4

[0050] The schematic diagram of this implementation is shown in Figure 1. Substrate 1 is a 128° Y-cut lithium niobate crystal 1 on which metallic aluminum (2) and lead pins 3 are deposited (on top of the crystal). The lead pins 3 are made by depositing a layer of gold on the aluminum surface. The lithium niobate is 6 mm long, 3 mm wide, and 250 μm thick. For detailed device composition, refer to [reference needed]. Figure 3 A heating resistor is deposited in the center of the device surface, with lead pins 3 designed at the edges. Surface weighted resistance reference. Figure 9The aluminum thin film 2 is arranged in a basic serpentine structure, with the resistance thickness and width weighted together. At the edges, the resistance width is smaller and the thickness is thinner, while in the center, the resistance width is larger and the thickness is thicker. The resistance width follows a quadratic function distribution opening downwards along the x-direction, and the resistance thickness also follows a quadratic function distribution opening downwards along the y-direction. The resistance thickness varies from 2µm to 40µm, and the width also varies from 2µm to 40µm, with a length of approximately 23cm. The weighted resistance wire 2 is connected to the lead pin 3, as shown in the reference diagram. Figure 6 Quadrilateral lead pins 3 are deposited on both sides of the weighted resistance wire to establish electrical connection points to the outside world, while blank pins are left to increase the connection stability of the device. The results in the numerical simulation are referenced below. Figure 7 It can be seen that the middle part of the surface has extremely high temperature uniformity, and the temperature gradient reference... Figure 8 It can be seen that a temperature gradient of <0.0005K / um and a temperature difference of <0.1K can be achieved within a surface thickness of 1.8mm to 4.2mm.

[0051] As can be seen from the above detailed description of the present invention, the micro heater with ultra-high local surface temperature uniformity provided by the present invention, by depositing serpentine heating resistance wire 2 and lead pin 3 on the surface of substrate 1, and using a weighting function to independently or in combination weight the thickness and / or width of the serpentine heating resistance along the length direction of substrate 1, makes the local surface of the micro heater have ultra-high temperature uniformity, thereby improving the selectivity, sensitivity and response of the gas sensor.

[0052] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art should understand that modifications or equivalent substitutions to the technical solutions of the present invention do not depart from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A microheater with localized ultra-high surface temperature uniformity, comprising: The substrate (1), the serpentine heating resistance wire (2), and the lead pins (3) connecting the serpentine heating resistance wire (2) are characterized in that the serpentine heating resistance wire (2) is deposited at the center of the upper or lower surface of the substrate (1); the lead pins (3) are symmetrically placed on both sides of the serpentine heating resistance wire (2) along the length direction of the substrate (1) and are electrically connected to the serpentine heating resistance wire (2) and the outside; wherein, The serpentine heating resistance wire (2) is folded and arranged with the same length along the width direction of the substrate (1), and folded and arranged with equal spacing along the length direction of the substrate (1); wherein, The resistance value of the serpentine heating resistance wire (2) varies along the length direction of the substrate (1) according to a weight function that varies along the length direction of the substrate (1), including: the thickness and / or width of the serpentine heating resistance wire (2) is changed along the length direction of the substrate (1) according to the weight function to change the resistance value of the serpentine heating resistance wire (2), so that the serpentine heating resistance wire (2) has the minimum width and / or thickness near the edge of the substrate (1), and the maximum width and / or thickness at the corresponding position at the center of the substrate (1).

2. The microheater with localized ultra-high surface temperature uniformity according to claim 1, characterized in that, The weighting function includes: cosine function, quadratic function, trigonometric wave function, Gaussian function or Sinc function.

3. The microheater with localized ultra-high surface temperature uniformity according to claim 2, characterized in that, The weights of the weight function vary between 1 and 10.

4. The microheater with localized ultra-high surface temperature uniformity according to claim 1, characterized in that, The width of the serpentine heating resistance wire (2) is independently weighted along the length direction of the substrate (1) according to the weight function, or the thickness of the serpentine heating resistance wire (2) is independently weighted along the length direction of the substrate (1) according to the weight function, or the thickness and width of the serpentine heating resistance wire (2) are simultaneously weighted along the length direction of the substrate (1) according to the weight function.

5. The microheater with locally ultra-high surface temperature uniformity according to claim 1, characterized in that, The substrate (1) has a single serpentine heating resistance wire (2) or multiple serpentine heating resistance wires (2) on its surface; wherein, multiple serpentine heating resistance wires are deposited side by side on the surface of the substrate (1) along the width direction of the substrate (1).

6. The microheater with locally ultra-high surface temperature uniformity according to claim 1, characterized in that, The materials of the serpentine heating resistance wire (2) include: metallic materials, composite metallic materials or semiconductor materials; the width and thickness of the serpentine heating resistance wire (2) are in the nanometer to micrometer range.

7. The microheater with locally ultra-high surface temperature uniformity according to claim 1, characterized in that, The serpentine heating resistance wire (2) is deposited on the surface of the substrate (1) using a surface deposition process. The surface deposition method includes physical vapor deposition or chemical vapor deposition.

8. The microheater with localized ultra-high surface temperature uniformity according to claim 1, characterized in that, The lead pin (3) includes a metal or composite film metal pin, and the lead pin (3) is deposited on the surface of the substrate (1) by a surface deposition process.

9. The microheater with localized ultra-high surface temperature uniformity according to claim 1, characterized in that, The substrate (1) is made of piezoelectric material, semiconductor material or polymer material.

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