Infrared thermoelectric sensing chip and radiation temperature measuring device

Abstract

The invention relates to the technical field of semiconductor devices, discloses an infrared thermoelectric sensing chip, a radiation temperature measurement device and a design method of an infrared hot end sensing chip, and is used for solving the technical problems that an infrared thermoelectric sensing chip in the prior art is poor in temperature measurement effect, is easily influenced by interference signals and is relatively low in detection precision. The infrared thermoelectric sensing chip comprises a supporting layer arranged above a substrate layer; a thermopile unit disposed over the support layer; the thermopile unit comprises a couple layer composed of a plurality of couple strips, a reflecting layer covers one end of the couple layer to form a cold end of the thermopile unit, and the other end of the couple layer forms a hot end of the thermopile unit; and the hot end area size of the galvanic couple layer is greater than or equal to the cold end area size of the galvanic couple layer. According to the invention, the temperature measurement effect of the infrared thermoelectric sensing chip is improved, the influence of interference signals on temperature detection is reduced, and the temperature detection precision is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor devices, and in particular to an infrared thermoelectric sensor chip, a radiation temperature measuring device and a design method of an infrared hot end sensor chip. Background Art

[0002] With the continuous development of infrared thermopile sensor applications, radiation temperature measurement has more and more applications and demands in different scenarios; accordingly, the requirements for the stability and sensitivity of the signal transmission of the thermopile system are getting higher and higher. For example, in the application of radiation temperature measurement scenarios, the sensor chip will face the signals brought by three heat transfer modes: thermal radiation, thermal convection and thermal conduction at the same time, but only the thermal radiation signal of the temperature measurement target itself is the effective signal that needs to be detected, and in addition to the effective signal, it also contains interference signals; for example, in the temperature measurement scenario, the external thermal radiation signal in the space and the internal thermal radiation signal caused by the heat dissipation of the package will directly superimpose on the measured signal to cause interference; the thermal conduction signal generated by the package and passed to the chip substrate will indirectly superimpose on the measured signal through the thermal conduction of the substrate to generate a temperature gradient at the hot and cold ends of the thermopile, causing interference; the thermal convection signal generated by the package and passed to the air between the chip and the package will indirectly superimpose on the measured signal through the thermal convection of the air to generate a temperature gradient at the hot and cold ends of the thermopile, causing interference, etc.; these interference factors are the main challenges in solving the signal stability problem.

[0003] The common anti-interference method in the prior art is to circumvent it through the signal processing program realized by the later intelligent algorithm, and it is mainly aimed at the pattern recognition and processing of "external thermal radiation signal", but the processing effect of other interference signals is poor, and the design and processing of the algorithm are relatively complicated. Therefore, there is an urgent need for an infrared thermoelectric sensor chip that can reduce interference signals and improve detection accuracy to solve the problems of infrared thermoelectric sensor chips in the prior art. Summary of the invention

[0004] The main purpose of the present invention is to solve the technical problems in the prior art that the infrared thermoelectric sensor chip has poor temperature measurement effect, is easily affected by interference signals, and has low detection accuracy.

[0005] The first aspect of the present invention provides an infrared thermoelectric sensor chip, characterized in that it comprises:

[0006] a support layer disposed above the substrate layer;

[0007] A thermopile unit disposed above the support layer;

[0008] The thermopile unit comprises an electric couple layer composed of a plurality of electric couple strips, one end of the electric couple layer is covered with a reflective layer to form a cold end of the thermopile unit, and the other end of the electric couple layer forms a hot end of the thermopile unit;

[0009] And the hot end area size of the electric double layer is greater than or equal to the cold end area size of the electric double layer.

[0010] Optionally, in a first implementation of the first aspect of the present invention, the relationship between the hot end area size and the cold end area size of the infrared thermoelectric sensor chip satisfies that the difference between the thermal response time constant of the cold end and the thermal response time constant of the hot end is minimum.

[0011] Optionally, in a second implementation of the first aspect of the present invention, the infrared thermoelectric sensor chip includes two thermopile units;

[0012] The two thermopile units are arranged in parallel along the diagonal line of the support layer, and when arranged in parallel, the cold ends and the hot ends of the two thermopile units are arranged in opposite directions.

[0013] Optionally, in a third implementation of the first aspect of the present invention, the shape of the galvanic strip is a rectangle;

[0014] When the galvanic strips are arranged side by side, the starting positions of the galvanic strips have certain equal intervals, so that the galvanic strips are arranged in a "V" shape;

[0015] The reflective layer is located at the upper half of the "V" in the "V"-shaped galvanic strip.

[0016] Optionally, in a fourth implementation of the first aspect of the present invention, the shape of the galvanic strip is a trapezoid;

[0017] The reflective layer is located at a side of the bottom of the trapezoidal galvanic strip where the length is shorter.

[0018] Optionally, in a fifth implementation of the first aspect of the present invention, a rectangular optical viewing area window is further provided on the infrared thermoelectric sensor chip;

[0019] The rectangular outline of the rectangular optical viewing area window is parallel to the outline of the substrate of the infrared thermoelectric sensor chip;

[0020] The hot end of the electric double layer in the infrared thermoelectric sensor chip is within the range of the rectangular optical viewing area window.

[0021] Optionally, in a sixth implementation of the first aspect of the present invention, an absorption layer is further covered on the electric double layer.

[0022] Optionally, in a seventh implementation of the first aspect of the present invention, a reflective layer is further provided below the electric double layer on the hot end side of the thermopile unit.

[0023] A second aspect of the present invention provides a radiation temperature measurement device, comprising: any one of the infrared thermal sensor chips described above.

[0024] A third aspect of the present invention provides a method for designing an infrared thermoelectric sensor chip, comprising: comprising any one of the infrared thermoelectric sensor chips described above;

[0025] Calculate the hot-end time constant and the cold-end time constant according to the reflective layer material parameters and the electric double layer material parameters of the infrared thermoelectric sensor chip;

[0026] The hot end area size and the cold end area size of the infrared thermoelectric sensor chip are determined based on the hot end material area size and the cold end material area size when the difference between the cold end time constant and the hot end time constant is the smallest.

[0027] The technical solution provided by the present invention includes a support layer arranged above the substrate layer; a thermopile unit arranged above the support layer; the thermopile unit includes an electric couple layer composed of a plurality of electric couple strips, one end of the electric couple layer is covered with a reflective layer to form the cold end of the thermopile unit, and the other end forms the hot end of the thermopile unit; and the hot end area size of the electric couple layer is greater than or equal to the cold end area size of the electric couple layer. The present invention improves the temperature measurement effect of the infrared thermoelectric sensor chip, reduces the influence of interference signals on temperature detection, and improves the accuracy of temperature detection. The design method of the radiation temperature measurement device and infrared thermoelectric sensor chip provided by the present invention also solves the corresponding technical problems. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0029] Figure 1 This is a schematic diagram of the first type of thermocouple strip shape of the infrared thermoelectric sensor chip in an embodiment of the present invention;

[0030] Figure 2 This is a schematic diagram of a first arrangement of thermocouple strips of an infrared thermoelectric sensor chip in an embodiment of the present invention;

[0031] Figure 3 This is a cross-sectional view of the first structure of the infrared thermoelectric sensor chip in the embodiment of the present invention;

[0032] Figure 4 This is a cross-sectional view of the structure of an electric couple layer and a reflective layer of an infrared thermoelectric sensor chip in an embodiment of the present invention;

[0033] Figure 5 A top view of the structure of an electric couple layer and a reflective layer of an infrared thermoelectric sensor chip in an embodiment of the present invention;

[0034] Figure 6 A top view of a first structure of an infrared thermoelectric sensor chip in an embodiment of the present invention;

[0035] Figure 7 A second structural cross-sectional view of the infrared thermoelectric sensor chip in an embodiment of the present invention;

[0036] Figure 8 This is a third structural cross-sectional view of the infrared thermoelectric sensor chip in the embodiment of the present invention;

[0037] Fig. 9 This is a fourth structural cross-sectional view of the infrared thermoelectric sensor chip in the embodiment of the present invention;

[0038] Fig.10 This is a schematic diagram of a second arrangement of the thermoelectric strips of the infrared thermoelectric sensor chip in an embodiment of the present invention;

[0039] Fig.11 A top view of a second structure of an external thermoelectric sensor chip in an embodiment of the present invention;

[0040] Fig.12 This is a schematic diagram of the second type of thermocouple strip shape of the thermoelectric sensor chip in the embodiment of the present invention;

[0041] Fig.13 This is a schematic diagram of a third arrangement of the thermoelectric strips of the infrared thermoelectric sensor chip in an embodiment of the present invention;

[0042] Fig.14 It is a top view of the third structure of the infrared thermoelectric sensor chip in the embodiment of the present invention. DETAILED DESCRIPTION

[0043] Exemplary embodiments of the present invention will now be described more fully with reference to the accompanying drawings. However, exemplary embodiments can be implemented in a variety of forms, and should not be construed as limiting the present invention to the embodiments set forth herein. On the contrary, providing these exemplary embodiments enables the present invention to be more comprehensive and complete, and is more convenient for fully conveying the inventive concept to those skilled in the art. The same reference numerals in the figures represent the same or similar elements, components or parts, and thus their repeated description will be omitted.

[0044] Under the premise of being consistent with the technical concept of the present invention, the features, structures, characteristics or other details described in a specific embodiment do not exclude that they can be combined in one or more other embodiments in a suitable manner.

[0045] In the description of specific embodiments, the features, structures, characteristics or other details described in the present invention are intended to enable those skilled in the art to fully understand the embodiments. However, it does not exclude that those skilled in the art can practice the technical solutions of the present invention without one or more of the specific features, structures, characteristics or other details.

[0046] The flowcharts shown in the accompanying drawings are only exemplary and do not necessarily include all the contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps can be decomposed, and some operations / steps can be combined or partially combined, so the actual execution order may change according to actual conditions.

[0047] The color codes in the drawings are only used to enhance the visual effect and distinguish different parts, and do not necessarily represent the colors of the actual objects.

[0048] The block diagrams shown in the accompanying drawings are only functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software form, or in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices. The term "and / or" or "and / or" includes all combinations of any one or more of the associated listed items.

[0049] See also Figure 1-Figure 9 The first embodiment of the infrared thermoelectric sensor chip in the embodiment of the present invention includes:

[0050] The infrared thermoelectric sensor chip described in this embodiment includes a thermopile structure, which is composed of thermocouple strips; for details, please refer to Figure 1 , the galvanic strip may be rectangular; the thermopile structure may be composed of a plurality of galvanic strips, and the specific layout design may be to arrange galvanic strips of equal length side by side; specifically, the thermopile structure taking a combination of 5 rectangular galvanic strips as an example is as follows Figure 2 shown.

[0051] Please continue reading Figure 3-Figure 6 The infrared thermoelectric sensor chip includes a substrate 101, an etching cavity 102, a support layer 103, an electric double layer 104 and a reflective layer 105; in a first implementation of the present embodiment, each infrared thermoelectric sensor chip includes two thermopile units, the reflective layer 105 is only located at one end above to constitute the cold end of the thermopile unit, and the end above the electric double layer 104 without the reflective layer constitutes the hot end of the thermopile unit; and the two thermopile units are arranged in parallel, and when arranged in parallel, the cold ends and hot ends of the two thermopile units are set in reverse.

[0052] Take a specific example to illustrate, the substrate 101 can be a polysilicon substrate, the etching cavity 102 can be made by back etching technology; the support layer 103 can be made of silicon nitride, the electric couple layer can be a poly+Metal structure (electrical couple process structure of polysilicon and metal) or N-poly+P-poly structure (electrical couple process structure of N-type polysilicon and P-type polysilicon); the reflective layer 105 can be made of aluminum. The above description of specific materials and manufacturing processes is only a specific embodiment of the present invention, and should not be regarded as a limitation on the infrared thermoelectric sensor chip described in the present invention.

[0053] In this embodiment, due to the presence of the support layer 103, the cold end and the hot end of the thermopile unit do not contact the substrate 101, that is, the cold end and the hot end are both symmetrically suspended on the medium of the support layer 103 through the double suspension design of the cold and hot ends, so that heat conduction and heat convection will not produce thermal gradients to the thermopile itself, which can greatly improve the signal stability. However, since the cold end cannot contact the substrate 101, the dynamic range of the output signal is reduced. In order to improve the signal stability while reducing the loss of sensitivity, it is necessary to maximize the temperature difference brought to the hot and cold ends by the thermal radiation signal of the temperature measurement target itself in this embodiment. In a specific embodiment, the hot end can be added or the cold end can be subtracted, so that the cold end receives less heat and the hot end receives more heat. The calculation formula for the thermal time constant of the material is:

[0054]

[0055] Among them, C is the heat capacity of the material, G is the thermal conductivity of the material, c is the specific heat capacity of the material, m is the mass, k is the thermal conductivity of the material, ρ is the density of the material, L is the thickness of the body material in the direction of heat flow, and A is the area of ​​the body material in the direction perpendicular to the heat flow. From the above formula, it can be seen that the thermal time constant can be significantly changed by adjusting the structural parameter "L".

[0056] Please continue reading Figure 4 as well as Figure 5 In this embodiment, a rectangular thermocouple in which the heat flow is parallel to the layers is taken as an example, material 1 is selected as the material of the electric double layer 104, and material 2 is selected as the material of the reflective layer 105; the side lengths of the electric double layer 104 and the reflective layer 105 are a1, b1 and a2, b2 respectively; the relationship between these parameters can be expressed as:

[0057] d2=α1d1, a2=α2a1, b2=α3b3;

[0058] Wherein, α1, α2 and α3 are proportional factors, the value range of α1 is (0, 1], the value range of α2 is [1, +∞), and the value range of α3 is (0, 1);

[0059] Taking α1=1, α2=1 as an example, by adjusting the proportional factor α3 (equivalent to adjusting "L"), the difference R between the thermal response time constants of the cold end and the hot end can be reduced. diff After calculation, the thermal response time constant R of the cold end is obtained. cold and the thermal response time constant R of the hot end hot They are:

[0060]

[0061] Among them, the specific heat capacity of material 1 is c1, the density is ρ1, the thermal conductivity is k1, and the thickness is d1; the specific heat capacity of material 2 is c2, the density is ρ2, the thermal conductivity is k2, and the thickness is d2;

[0062] Therefore, the difference in thermal response time constant R diff for:

[0063]

[0064] Assume that the material factor of the cold end is M2 and the material factor of the hot end is M1, that is:

[0065]

[0066] Let α3=x, x∈(0,1), so:

[0067] y=x 2 M2-(1-x) 2 M1=(M2-M1)x 2 +2M1x-M1;

[0068] That is:

[0069] y(x=0)=-M1<0;

[0070] y(x=1)=M2>0;

[0071]

[0072] In general, to ensure that the hot end absorbs enough heat, the value of α3 should not exceed therefore:

[0073] 1) If the material parameters of the hot and cold ends are such that but Time R diff Minimum;

[0074] 2) If the material parameters of the hot and cold ends are such that but Time R diff Minimal, exact match.

[0075] In summary, this embodiment can control the area of ​​the hot end and the cold end receiving heat radiation by increasing or reducing the material design of the hot and cold ends, that is, adjusting the proportional factor α3 (equivalent to adjusting "L"), which can effectively reduce R diff , but its actual optimization effect depends on the material factors, and when optimized, the thermal time constants of the hot and cold ends can be fully matched.

[0076] Please continue reading Figure 6 In the first implementation of the present embodiment, the layout design of each thermopile unit is placed along the diagonal direction of the substrate 101 and the support layer 103. When the shape of the infrared thermoelectric sensor chip is a square, since the length of the diagonal is longer than the side length, if the thermocouple is arranged in this diagonal direction, the cold and hot nodes of the same thermopile can be pulled apart by a longer distance. Specifically, the two thermopile units are arranged side by side along the diagonal of the infrared thermoelectric sensor chip or along the diagonal of the support layer 103; and the cold ends and hot ends of the two thermopile units are arranged in reverse, so that the two thermopile units are centrally symmetrical with the center point of the substrate 101. Such a symmetrical method can achieve a greater distance between the cold and hot nodes of the thermopile, and fewer thermocouple units can be used when the same or even higher temperature difference can be achieved, which is more conducive to reducing the internal resistance in the signal sensing process.

[0077] Please continue reading Figure 6 In another implementation of this embodiment, a rectangular optical viewing window is also provided on the electric thermal pile unit, and the portion within the rectangular optical viewing window can receive the thermal radiation signal of the temperature measurement target, while the portion outside the rectangular optical viewing window is shielded, so as to minimize the area of ​​the reflective layer within the rectangular optical viewing window while ensuring that the hot end is completely within the rectangular optical viewing window. In this way, the thermal radiation signal of the temperature measurement target itself is more focused on the "infrared radiation area" within the rectangular optical viewing window. This fully symmetrical design, both in terms of optics and chip structure, is more conducive to improving the stability of signal infrared signal sensing.

[0078] See also Figure 7 In another implementation of the present embodiment, the infrared thermoelectric sensor chip includes a substrate 101, an etching cavity 102, a support layer 103 and an electric double layer 104, and also includes an absorption layer 106 above the electric double layer 104, and a reflection layer 105 arranged above the absorption layer 106; specifically, the absorption layer 106 is located above the electric double layer 104, and the reflection layer 105 is arranged above one end of the absorption layer 106, constituting the cold end of the thermopile unit; the other end without the reflection layer 105 constitutes the hot end of the thermopile unit; the temperature difference between the two ends of the electric double layer 104 is increased through such a structural design.

[0079] See also Figure 8In another implementation of the present embodiment, the infrared thermoelectric sensor chip in the present embodiment includes a substrate 101, an etching cavity 102, a support layer 103 and an electric double layer 104, and an absorption layer 106 arranged above the electric double layer 104; a reflection layer 105 is arranged above one end of the absorption layer 106 to form a cold end, and a reflection layer 105 is arranged below the other end of the absorption layer 106 to form a hot end; the design of the reflection layer 105 in this embodiment can increase the temperature difference between the two ends of the electric double layer.

[0080] See also Fig. 9 In another implementation of this embodiment, in the aforementioned Figure 8 On the basis of the structure shown, an absorption enhancement layer 107 is further included above the absorption layer 106, and the absorption enhancement layer 107 covers the entire area of ​​the absorption layer 106; a reflection layer 105 is provided above one end of the absorption layer 106 and the absorption enhancement layer 107 to form a cold end, and a reflection layer 105 is provided below the other end of the absorption layer 106 and the absorption enhancement layer 107 to form a hot end. By providing the absorption enhancement layer 107, it is possible to prevent the absorption layer 106 at the hot end from transmitting light and the reflection layer 105 below from reflecting part of the thermal radiation signal of the temperature measurement target itself, thereby further increasing the temperature difference between the two ends.

[0081] The present invention improves the temperature measurement effect of the infrared thermoelectric sensor chip, reduces the influence of the thermal non-equilibrium state of the chip itself caused by the change of ambient temperature on the temperature measurement effect; and, through the structural addition and subtraction material design, the thermal time constants at both ends of the cold end are matched, which is simpler than material design and production; at the same time, the present invention also makes the temperature difference between the cold and hot ends larger through structural design, reduces the influence of interference signals on temperature detection, and improves the accuracy of temperature detection.

[0082] See also Figure 1 , Figure 3 as well as Figure 7-11 The second embodiment of the infrared thermoelectric sensor chip in the embodiment of the present invention includes:

[0083] The infrared thermoelectric sensor chip described in this embodiment also includes a thermopile structure, which is composed of thermocouple strips; for details, please refer to Figure 1 The galvanic strip may be rectangular; the thermopile structure may be composed of a plurality of galvanic strips, and the specific layout design may be to arrange galvanic strips of equal length side by side; specifically, when the galvanic strips are arranged, the positions of adjacent galvanic strips may be staggered with each other, so that the center points of the galvanic strips are not on the same straight line, and in this way, the hot end area size and the cold end area size of the infrared thermoelectric sensor chip are adjusted.

[0084] For a specific example, please refer to Fig.10 as well as Fig.11 , from the two side strips to the middle strip, when the strips are arranged side by side, the starting positions of the strips have a certain equidistant interval, and the strips are symmetrical on the left and right, forming a "V" shape arrangement, and then the reflective layer is set in the upper half of the "V" shape of the "V" shaped strip, that is, the upper half of the "V" in the "V" shaped strip to obtain the thermoelectric pile structure; the reflective layer can cover the area of ​​the strip that is smaller than the uncovered area, so that the area of ​​the hot end is increased and the area of ​​the cold end is reduced. Specifically, the specific dimensions of the cold end and the hot end of the thermoelectric pile structure described in this embodiment can be designed based on the scheme in the first embodiment described above and based on the thermal response time constants of the cold end and the hot end; the specific calculation can be performed through simulation and other methods, which will not be repeated here.

[0085] Please continue reading Figure 3 and Fig.11 In the first implementation of the present embodiment, the infrared thermoelectric sensor chip includes a substrate 101, an etching cavity 102, a support layer 103, an electric double layer 104 and a reflective layer 105; the reflective layer 105 is only located at one end above the electric double layer 104 to form the cold end of the thermopile unit, and the end above the electric double layer 104 without the reflective layer forms the hot end. In the present embodiment, the reflective layer 105 is located at one end of the thermopile unit, and combined with the aforementioned design of staggered electric double strips, the reflective layer 105 can cover an area of ​​the electric double strips that is smaller than the uncovered area, so that the area of ​​the hot end is increased and the area of ​​the cold end is reduced, further increasing the temperature difference between the two ends.

[0086] Please continue reading Fig.11 In this embodiment, the layout design of each thermopile unit is placed along the diagonal of the infrared thermoelectric sensor chip, that is, the diagonal direction of the substrate 101 and the support layer 103, and the two thermopile units are centrally symmetrical about the center point of the substrate 101 or the support layer 103. Such a symmetric manner can achieve a greater distance between the cold and hot nodes of the thermopile, and fewer thermocouple units can be used when the same or even higher temperature difference can be achieved, which is more conducive to reducing the internal resistance in the signal sensing process.

[0087] The layout design of each thermopile unit is placed along the diagonal direction of the support layer 103, and the two thermopile units are centrally symmetrical about the center point of the support layer 103. Such a symmetric manner can achieve a greater distance between the cold and hot nodes of the thermopile, and fewer thermocouple units can be used when the same or even higher temperature difference can be achieved, which is more conducive to reducing the internal resistance in the signal sensing process.

[0088] In one implementation of this embodiment, a rectangular optical viewing window is also provided on the electric thermal pile unit, and the portion within the rectangular optical viewing window can receive the thermal radiation signal of the temperature measurement target, while the portion outside the rectangular optical viewing window is shielded to reduce the thermal radiation signal of the temperature measurement target that can be received. In this way, the thermal radiation signal of the temperature measurement target itself is more focused on the "infrared radiation area" within the rectangular optical viewing window. This fully symmetrical design, both in terms of optics and chip structure, is more conducive to improving the stability of signal infrared signal sensing.

[0089] For further information, see Figure 7-9 In other implementations of this embodiment, an absorption layer 106 may be covered on the electric double layer in the infrared thermoelectric sensor chip, a reflection layer 105 may be provided on the electric double layer 104 and one end of the absorption layer 106 to form a cold end, and the other end may be used as a hot end; an absorption layer 106 may also be covered on the electric double layer 104, and a reflection layer 105 may be provided on one end of the absorption layer 106 in the infrared thermoelectric sensor chip to form a cold end, and a reflection layer 105 may be provided below the other end of the absorption layer 106 to form a hot end; further, an absorption enhancement layer 107 may be added on the absorption layer 106. The specific contents are basically similar to those in the aforementioned embodiments, and will not be repeated here.

[0090] The present invention improves the temperature measurement effect of the infrared thermoelectric sensor chip, reduces the influence of the thermal non-equilibrium state of the chip itself caused by the change of ambient temperature on the temperature measurement effect; and, through the structural addition and subtraction material design, the thermal time constants at both ends of the cold end are matched, which is simpler than material design and production; at the same time, the present invention also makes the temperature difference between the cold and hot ends larger through structural design, reduces the influence of interference signals on temperature detection, and improves the accuracy of temperature detection.

[0091] See also Figure 3 , Figure 7-9 as well as Figure 12-14 , the third embodiment of the infrared thermoelectric sensor chip in the embodiment of the present invention includes:

[0092] For details, please refer to Fig.12 The infrared thermoelectric sensor chip described in this embodiment includes a thermopile structure composed of trapezoidal thermocouple strips. Fig.13 The layout of each galvanic strip is designed to arrange the trapezoidal galvanic strips side by side. Since each galvanic strip is designed in a trapezoidal shape, when arranged side by side, it can form a thermopile structure similar to a trapezoidal or fan-shaped structure. Furthermore, when arranging the galvanic strips, the distance between each other is kept uniform.

[0093] The infrared thermoelectric sensor chip includes a substrate 101, an etching cavity 102, a support layer 103, an electric double layer 104 and a reflective layer 105; in the first implementation of the present embodiment, the reflective layer 105 is only located at one end above to constitute a cold end, and the end above the electric double layer 104 without the reflective layer constitutes a hot end. Fig.14 The reflecting layer 105 is arranged on one side of the bottom of each galvanic strip where the length is shorter. In this way, the reflecting layer 105 can cover an area of ​​the galvanic strip that is smaller than the uncovered area, so that the area of ​​the hot end is increased and the area of ​​the cold end is reduced. Specifically, the specific dimensions of the cold end and the hot end of the thermopile structure described in this embodiment can be designed based on the thermal response time constants of the cold end and the hot end based on the scheme in the first embodiment mentioned above, so as to further increase the temperature difference between the two ends. The specific calculation can be performed through simulation and the like, which will not be repeated here.

[0094] Please continue reading Fig.14 The layout of each thermopile unit is designed to be placed along the diagonal of the infrared thermoelectric sensor chip, that is, the diagonal direction of the substrate 101 and the support layer 103, and the two thermopile units are centrally symmetrical about the center point of the substrate 101 or the support layer 103. Such a symmetric method can achieve a greater distance between the cold and hot nodes of the thermopile, and fewer thermocouple units can be used when the same or even higher temperature difference can be achieved, which is more conducive to reducing the internal resistance in the signal sensing process.

[0095] In one implementation of this embodiment, a rectangular optical viewing window is also provided on the electric thermal pile unit, and the portion within the rectangular optical viewing window can receive the thermal radiation signal of the temperature measurement target, while the portion outside the rectangular optical viewing window is shielded to reduce the thermal radiation signal of the temperature measurement target that can be received. In this way, the thermal radiation signal of the temperature measurement target itself is more focused on the "infrared radiation area" within the rectangular optical viewing window. This fully symmetrical design, both in terms of optics and chip structure, is more conducive to improving the stability of signal infrared signal sensing.

[0096] Furthermore, in other implementations of this embodiment, an absorption layer 106 may be covered on the electric double layer 104 in the infrared thermoelectric sensor chip, and a reflection layer 105 may be provided on one end of the electric double layer 104 and the absorption layer 106 to form the cold end of the thermopile unit, and the other end may serve as the hot end of the thermopile unit; an absorption layer 106 may also be covered on the electric double layer 104, and a reflection layer 105 may be provided on one end of the absorption layer 106 in the infrared thermoelectric sensor chip to form the cold end, and a reflection layer 105 may be provided below the other end of the absorption layer 106 to form the hot end; further, an absorption enhancement layer 107 may also be added on the absorption layer 106. For details, please refer to Figure 7-9The contents in the embodiment are basically similar to those in the aforementioned embodiment, so they will not be described again here.

[0097] The present invention improves the temperature measurement effect of the infrared thermoelectric sensor chip, reduces the influence of the thermal non-equilibrium state of the chip itself caused by the change of ambient temperature on the temperature measurement effect; and, through the structural addition and subtraction material design, the thermal time constants at both ends of the cold end are matched, which is simpler than material design and production; at the same time, the present invention also makes the temperature difference between the cold and hot ends larger through structural design, reduces the influence of interference signals on temperature detection, and improves the accuracy of temperature detection.

[0098] Based on the same inventive concept, a radiation temperature measurement device is also provided in this embodiment, and the radiation temperature measurement device includes: an infrared thermal sensor chip as described in the above embodiment of the claim. The specific corresponding description can refer to the above embodiment and will not be repeated here.

[0099] Based on the same inventive concept, the present embodiment also provides a design method for an infrared thermoelectric sensor chip, including an infrared thermal sensor chip as described in the above embodiment; specifically, the design method for the infrared thermoelectric sensor chip includes: calculating the hot-end time constant and the cold-end time constant according to the reflective layer material parameters and the electric double layer material parameters of the infrared thermoelectric sensor chip; determining the hot-end area size and the cold-end area size of the infrared thermoelectric sensor chip based on the hot-end material area size and the cold-end material area size when the difference between the cold-end time constant and the hot-end time constant is the smallest.

[0100] Furthermore, the design method of the infrared thermoelectric sensor chip also includes: obtaining the material parameters of the reflective layer and the material parameters of the electric double layer, and calculating the hot end time constant and the cold end time constant through computer simulation; determining the hot end area size and the cold end area size of the infrared thermoelectric sensor chip based on the hot end material area size and the cold end material area size when the difference between the cold end time constant and the hot end time constant is the smallest.

[0101] The present invention matches the thermal time constants at both ends of the cold end through structural material addition and subtraction design, which is simpler to manufacture than material design, reduces the influence of interference signals on temperature detection, and improves the accuracy of temperature detection.

[0102] The above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

[0103] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0104] The above is only an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. An infrared thermoelectric sensor chip, characterized in that: include: a support layer disposed above the substrate layer; A thermopile unit disposed above the support layer; The thermopile unit comprises an electric couple layer composed of a plurality of electric couple strips, one end of the electric couple layer is covered with a reflective layer to form a cold end of the thermopile unit, and the other end of the electric couple layer forms a hot end of the thermopile unit; And the hot end area size of the electric double layer is greater than or equal to the cold end area size of the electric double layer.

2. The infrared thermoelectric sensor chip according to claim 1, characterized in that: The relationship between the hot end area size and the cold end area size of the infrared thermoelectric sensor chip satisfies that the difference between the thermal response time constant of the cold end and the thermal response time constant of the hot end is minimum.

3. The infrared thermoelectric sensor chip according to claim 2, characterized in that: The infrared thermoelectric sensor chip includes two thermopile units; The two thermopile units are arranged in parallel along the diagonal line of the support layer, and when arranged in parallel, the cold ends and the hot ends of the two thermopile units are arranged in opposite directions.

4. The infrared thermoelectric sensor chip according to claim 3, characterized in that: The shape of the galvanic strip is rectangular; When the galvanic strips are arranged side by side, the starting positions of the galvanic strips have certain equal intervals, so that the galvanic strips are arranged in a "V" shape; The reflective layer is located at the upper half of the "V" in the "V"-shaped galvanic strip.

5. The infrared thermoelectric sensor chip according to claim 3, characterized in that: The shape of the galvanic strip is trapezoidal; The reflective layer is located at a side of the bottom of the trapezoidal galvanic strip where the length is shorter.

6. The infrared thermoelectric sensor chip according to claim 4 or 5, characterized in that: The infrared thermoelectric sensor chip is also provided with a rectangular optical viewing area window; The rectangular outline of the rectangular optical viewing area window is parallel to the outline of the substrate of the infrared thermoelectric sensor chip; The hot end of the electric double layer in the infrared thermoelectric sensor chip is within the range of the rectangular optical viewing area window.

7. The infrared thermoelectric sensor chip according to claim 6, characterized in that: The electric double layer is also covered with an absorption layer.

8. The infrared thermoelectric sensor chip according to claim 7, characterized in that: A reflective layer is further arranged below the electric double layer on the hot end side of the thermopile unit.

9. A radiation temperature measuring device, characterized in that: The radiation temperature measuring device comprises: The infrared thermal sensor chip according to any one of claims 1 to 8.

10. A design method for an infrared thermoelectric sensor chip, characterized in that: comprising an infrared thermoelectric sensor chip as described in any one of claims 1 to 8; Calculate the hot-end time constant and the cold-end time constant according to the reflective layer material parameters and the electric double layer material parameters of the infrared thermoelectric sensor chip; The hot end area size and the cold end area size of the infrared thermoelectric sensor chip are determined based on the hot end material area size and the cold end material area size when the difference between the cold end time constant and the hot end time constant is the smallest.

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