Infrared temperature sensor and preparation method thereof

Abstract

The invention discloses an infrared temperature sensor and a preparation method thereof, and belongs to the technical field of semiconductors. A channel layer, a barrier layer, a first electrode, a wave-absorbing dielectric layer and a wave-absorbing resonance layer are sequentially stacked on a first surface of a substrate of the infrared temperature sensor, and at least part of the outer contour of the orthographic projection of the wave-absorbing dielectric layer on the first surface exceeds the outer contour of the orthographic projection of the wave-absorbing resonance layer on the first surface. The second electrode is arranged on the second surface, penetrates through the substrate and is electrically connected with the channel layer. The first electrode, the wave-absorbing dielectric layer and the wave-absorbing resonance layer form the metamaterial infrared wave absorber, infrared waves can be perfectly absorbed on the corresponding wave band, the temperature can be increased, then electrons in the material move in the direction perpendicular to the surface of the material through the self-polarization effect of a heterostructure formed by the channel layer and the barrier layer, and therefore polarization surface charges are generated, and the wave-absorbing effect is improved. Current is formed through the first electrode and the second electrode, and temperature detection is achieved through the magnitude of the current.

Description

Technical Field

[0001] The present application belongs to the field of semiconductor technology, and in particular relates to an infrared temperature sensor and a preparation method thereof. Background Art

[0002] At present, temperature sensors still have problems such as low measurement accuracy, low sensitivity, or complex system and high manufacturing cost. Infrared temperature sensors in particular have low sensitivity and poor measurement accuracy, and their performance is greatly reduced or even fails in low temperature environments.

[0003] Based on this, how to improve the sensitivity of infrared temperature sensors has become an urgent problem to be solved in this field. Summary of the invention

[0004] The present application provides an infrared temperature sensor and a preparation method thereof, aiming to improve the sensitivity thereof.

[0005] In a first aspect, the present application provides an infrared temperature sensor, wherein the substrate comprises a first surface and a second surface opposite to each other, and the infrared temperature sensor further comprises a channel layer, a barrier layer, a first electrode, an absorbing medium layer and an absorbing resonance layer stacked in sequence on the first surface, wherein the outer contour of the positive projection of the absorbing medium layer on the first surface at least partially exceeds the outer contour of the positive projection of the absorbing resonance layer on the first surface. The infrared temperature sensor further comprises a second electrode, which is disposed on the second surface and penetrates the substrate and is electrically connected to the channel layer.

[0006] In some embodiments, the infrared temperature sensor includes a plurality of wave absorbing resonance layers, and the orthographic projections of the plurality of wave absorbing resonance layers on the first surface are located within the range of the orthographic projection of the wave absorbing medium layer on the first surface.

[0007] In some embodiments, the material of the channel layer includes at least one of gallium nitride, gallium arsenide, or indium gallium arsenide, and the material of the barrier layer includes at least one of indium gallium nitride, aluminum gallium nitride, indium phosphide, aluminum gallium arsenide, or indium aluminum arsenide.

[0008] In some embodiments, the infrared temperature sensor further includes a buffer layer disposed between the substrate and the channel layer, and the second electrode is electrically connected to the channel layer through the buffer layer.

[0009] In some embodiments, the material of the absorbing medium layer includes at least one of silicon oxide, silicon nitride or aluminum oxide.

[0010] In some embodiments, the material of the wave absorbing resonance layer includes at least one of gold, silver, aluminum, copper, platinum, palladium or titanium.

[0011] In some embodiments, the infrared temperature sensor further includes a hollow portion, and an orthographic projection of the hollow portion on the first surface surrounds an orthographic projection of the barrier layer on the first surface.

[0012] In some embodiments, the substrate includes a penetrating cavity, the second electrode is disposed on an inner wall of the cavity, and the second electrode is electrically connected to the channel layer through the cavity.

[0013] In a second aspect, the present application also provides a method for preparing an infrared temperature sensor, comprising the following steps S10 to S20: Step S10: providing a substrate, wherein the substrate comprises a first surface and a second surface opposite to each other.

[0014] Step S20: forming a stacked channel layer, a barrier layer, a first electrode, an absorbing medium layer and an absorbing resonance layer in sequence on the first surface, wherein an outer contour of an orthographic projection of the absorbing medium layer on the first surface at least partially exceeds an outer contour of an orthographic projection of the absorbing resonance layer on the first surface.

[0015] Step S30: forming a second electrode on the second surface, wherein the second electrode penetrates the substrate and is electrically connected to the channel layer.

[0016] In some embodiments, after forming the wave absorbing resonance layer and before forming the second electrode, the preparation method further includes steps S21 and S22: Step S21: etching the channel layer to form a hollow portion exposing the substrate, wherein the orthographic projection of the hollow portion on the first surface surrounds the orthographic projection of the barrier layer on the first surface; Step S22: etching the substrate to form a cavity communicating with the hollow portion.

[0017] In addition, forming the second electrode includes: forming the second electrode on the inner wall of the cavity, and the second electrode is electrically connected to the channel layer through the cavity.

[0018] In the infrared temperature sensor provided in the embodiment of the present application, the infrared temperature sensor includes a channel layer, a barrier layer, a first electrode, an absorbing medium layer and an absorbing resonance layer stacked in sequence on the first surface of the substrate, and also includes a second electrode arranged on the second surface of the substrate. The first electrode, the absorbing medium layer and the absorbing resonance layer form a metamaterial infrared absorber, which can perfectly absorb infrared waves in the corresponding band (absorption efficiency is as high as 100%), so that the temperature of the infrared temperature sensor rises rapidly.

[0019] Utilizing the pyroelectric properties and electrostrictive effect of the channel layer and the barrier layer, when the temperature changes, the self-polarization effect of the heterostructure composed of the channel layer and the barrier layer causes the electrons in the material to move in a direction perpendicular to the surface of the material, thereby generating polarized surface charges. The surface charges are discharged through the first electrode and the second electrode to form a current, and the temperature is detected by collecting the current size.

[0020] Since the metamaterial infrared absorber formed by the first electrode, the absorbing medium layer and the absorbing resonance layer can perfectly absorb infrared waves, its absorption efficiency for infrared waves is greater than that of traditional materials. Compared with the related art, under the same temperature change, the temperature rise of the infrared temperature sensor provided by the embodiment of the present application is more obvious, and thus a larger current can be generated, so that the infrared temperature sensor has a higher sensitivity.

[0021] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which: Figure 1 A top view of the infrared temperature sensor provided in an embodiment of the present application; Figure 2 for Figure 1 A cross-sectional view of the mid-infrared temperature sensor along the section line AA'; Figure 3 A flow chart of a method for preparing an infrared temperature sensor provided in an embodiment of the present application; Figure 4 to Figure 12 A diagram of the steps for preparing an infrared temperature sensor provided in an embodiment of the present application. DETAILED DESCRIPTION

[0023] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in some embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments provided by the present application, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present application.

[0024] Unless the context requires otherwise, throughout the specification and claims, the term "comprising" is to be construed in an open, inclusive sense, ie, meaning "including, but not limited to."

[0025] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present application, unless otherwise specified, "plurality" means two or more.

[0026] When describing some embodiments, the term "connection" and its derivative expressions may be used. The term "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. For example, when describing some embodiments, the term "connection" may be used to indicate that two or more components are in direct physical or electrical contact with each other.

[0027] Additionally, the use of “based on” is meant to be open and inclusive, as a process, step, calculation, or other action “based on” one or more stated conditions or values ​​may, in practice, be based on additional conditions or values ​​beyond those stated.

[0028] It will be understood that when a layer or an element is referred to as being on another layer or substrate, it can be directly on the other layer or substrate, or intervening layers may be present between the layer or element and the other layer or substrate.

[0029] Exemplary embodiments are described herein with reference to cross-sectional views that are idealized exemplary drawings. In the drawings, the thickness of layers and the area of ​​regions are exaggerated for clarity. Therefore, variations in shape relative to the drawings due to, for example, manufacturing techniques and / or tolerances are conceivable. Therefore, the exemplary embodiments should not be interpreted as being limited to the shapes of the regions shown herein, but include deviations in shape due to, for example, manufacturing. Therefore, the regions shown in the drawings are schematic in nature, and their shapes are not intended to illustrate the actual shape of regions of the device, and are not intended to limit the scope of the exemplary embodiments.

[0030] Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0031] In the related art, infrared temperature sensors have low sensitivity, poor measurement accuracy, unsatisfactory performance in low temperature environments, and a small measurement range.

[0032] To solve the above problems, the present application provides an infrared temperature sensor, such as Figure 1~Figure 2 As shown, Figure 1 This is a top view of the infrared temperature sensor provided in the embodiment of the present application. The dotted box in the figure corresponds to a sensing unit 100. Figure 2 for Figure 1 Cross-sectional view of the mid-infrared temperature sensor along section line AA'.

[0033] The substrate 11 of the infrared temperature sensor 10 includes a first surface P1 and a second surface P2 opposite to each other, and a channel layer 12, a barrier layer 13, a first electrode 14, an absorbing medium layer 15 and an absorbing resonance layer 16 are sequentially stacked on the first surface P1. The outer contour of the orthographic projection of the absorbing medium layer 15 on the first surface P1 at least partially exceeds the outer contour of the orthographic projection of the absorbing resonance layer 16 on the first surface P1.

[0034] The infrared temperature sensor 10 further includes a second electrode 17 disposed on the second surface P2 . The second electrode 17 penetrates the substrate 10 and is electrically connected to the channel layer 12 .

[0035] In the embodiment provided in the embodiment of the present application, the infrared temperature sensor 10 includes a channel layer 12, a barrier layer 13, a first electrode 14, an absorbing medium layer 15 and an absorbing resonance layer 16 which are sequentially stacked on the first surface P1 of the substrate 11. Among them, the first electrode 14, the absorbing medium layer 15 and the absorbing resonance layer 16 can form a metamaterial infrared absorber. When infrared waves are radiated into the metamaterial infrared absorber, the resonance of the absorbing resonance layer 16 is caused. During the resonance process, the photon energy of the infrared wave is converted into heat energy. In the corresponding band, the metamaterial infrared absorber can perfectly absorb infrared waves (absorption efficiency is as high as 100%), so that the temperature of the infrared temperature sensor 10 rises rapidly.

[0036] By utilizing the pyroelectric properties and electrostrictive effect of the channel layer 12 and the barrier layer 13, when the temperature changes, the self-polarization effect of the heterostructure formed by the channel layer 12 and the barrier layer 13 causes the electrons in the material to move in a direction perpendicular to the surface of the material, thereby generating polarized surface charges. The surface charges are discharged through the first electrode 14 and the second electrode 17 to form a current, and the temperature is detected by collecting the current size.

[0037] Since the metamaterial infrared absorber can perfectly absorb infrared waves, its absorption efficiency of infrared waves is greater than that of traditional materials. Compared with the related art, under the same temperature change, the temperature rise of the infrared temperature sensor 10 provided by the embodiment of the present application is more obvious, thereby forming a larger current, so that the infrared temperature sensor 10 has a higher sensitivity. In addition, the infrared temperature sensor with the above structure also has the advantages of strong anti-interference ability and high precision.

[0038] In some embodiments, Figure 1 As shown, the infrared temperature sensor 10 includes a plurality of absorbing resonance layers 16 , and the orthographic projections of the plurality of absorbing resonance layers 16 on the first surface P1 are located within the range of the orthographic projections of the absorbing medium layer 15 on the first surface P1 .

[0039] In the embodiment of the present application, a plurality of absorbing resonance layers 16 are arranged in the same layer, and one absorbing resonance layer 16 can be regarded as corresponding to one metamaterial infrared absorber unit, which can absorb infrared waves within a certain band. For example, the side length of a metamaterial infrared absorber unit along direction X or direction Y is within the range of 0.1 μm to 30 μm. By properly designing the absorbing resonance layer 16, the infrared wave band that can be absorbed by the metamaterial infrared absorber unit is within the range of 0.01 μm to 10 μm.

[0040] For example, Figure 1 The infrared temperature sensor 10 shown includes four wave-absorbing resonance layers 16. Through the reasonable design of the four wave-absorbing resonance layers 16, the infrared temperature sensor 10 can absorb infrared waves in a band range that is a superposition of four bands, thereby expanding the detection range of the infrared temperature sensor 10. And within the corresponding band range, the infrared temperature sensor 10 can achieve perfect absorption of infrared waves, so that the temperature of the infrared temperature sensor 10 rises rapidly, and then a large current can be formed, so that the infrared temperature sensor 10 has a higher sensitivity.

[0041] In some embodiments, the material of the channel layer 12 includes at least one of gallium nitride, gallium arsenide, or indium gallium arsenide, and the material of the barrier layer 13 includes at least one of indium gallium nitride, aluminum gallium nitride, indium phosphide, aluminum gallium arsenide, or indium aluminum arsenide.

[0042] The channel layer 12 and the barrier layer 13 are used to form a heterostructure, so that when the temperature changes, the self-polarization effect is utilized to make the electrons in the material move in a direction perpendicular to the surface of the material, thereby generating polarized surface charges. The surface charges are discharged through the first electrode 14 and the second electrode 17 to form a current, and then the temperature is detected by collecting the current size.

[0043] The above materials provided in the embodiments of the present application all have excellent pyroelectric properties and electrostrictive effects, and can produce more obvious current changes under the same temperature changes, thereby making the infrared temperature sensor 10 have higher sensitivity.

[0044] In some embodiments, Figure 2 As shown, the infrared temperature sensor 10 further includes a buffer layer 111 disposed between the substrate 11 and the channel layer 12 , and the second electrode 17 is electrically connected to the channel layer 12 through the buffer layer 111 .

[0045] The buffer layer 111 is used to improve the lattice mismatch problem and reduce the dislocation density. Based on this, the second electrode 17 is electrically connected to the channel layer 12 through the buffer layer 111. In the process of surface charges forming a current through the buffer layer 111 and the second electrode 17, the electron movement efficiency is improved, thereby improving the performance of the infrared temperature sensor 10.

[0046] In some embodiments, the material of the absorbing medium layer 15 includes at least one of silicon oxide, silicon nitride or aluminum oxide.

[0047] The above materials have strong intrinsic absorption capabilities for specific infrared bands. For example, silicon nitride has strong intrinsic absorption capabilities in long-wave infrared (7.5μm~14μm). Using the above materials to form the absorbing medium layer 15 can enhance the absorption efficiency of the metamaterial infrared absorber in the corresponding band, making the temperature rise of the infrared temperature sensor 10 more obvious, and then a larger current can be formed, so that the infrared temperature sensor 10 has a higher sensitivity.

[0048] In some embodiments, the material of the wave absorbing resonance layer 16 includes at least one of gold, silver, aluminum, copper, platinum, palladium or titanium.

[0049] Different materials exhibit good plasmon properties in different bands. The metamaterial infrared absorber can enhance the local field strength of light through its plasmon properties, thereby improving the absorption efficiency of the metamaterial infrared absorber. The working wavelength and bandwidth of the metamaterial infrared absorber can be adjusted by reasonably designing the size of the absorbing resonance layer 16 of different materials, and the infrared wave can be efficiently absorbed in a specific band, so that the temperature rise of the infrared temperature sensor 10 is more obvious, and a larger current can be formed, so that the infrared temperature sensor 10 has a higher sensitivity.

[0050] In some embodiments, Figure 1 As shown, the infrared temperature sensor 10 further includes a hollow portion L0 , and the orthographic projection of the hollow portion L0 on the first surface P1 surrounds the orthographic projection of the barrier layer 13 on the first surface P1 .

[0051] The setting of the hollow portion L0 can reduce the conduction loss of heat in the solid, so that the temperature increased after the metamaterial infrared absorber absorbs infrared waves can be retained as much as possible in the absorbing medium layer 15 and the absorbing resonance layer 16 under the first electrode 14, which is conducive to the self-polarization effect of the heterostructure and the generation of a more stable current, thereby improving the measurement sensitivity and measurement accuracy.

[0052] In some embodiments, Figure 2 As shown, the substrate 11 includes a penetrating cavity K0 , the second electrode 17 is disposed on the inner wall of the cavity K0 , and the second electrode 17 is electrically connected to the channel layer 12 via the cavity K0 .

[0053] The setting of the cavity K0 can also reduce the conduction loss of heat in the solid, and avoid the temperature increase after the metamaterial infrared absorber absorbs infrared waves and then dissipates heat through the substrate 11. Exemplarily, in some embodiments, the hollow portion L0 and the cavity K0 work together to make the infrared temperature sensor 10 have a suspended island structure surrounded by the hollow portion L0. Based on this, the increased temperature is retained as much as possible in the suspended island structure, which is conducive to the self-polarization effect of the heterostructure and the generation of a more stable current. In addition, the electrons do not need to pass through the substrate 11 during the movement process, and can directly form a current through the second electrode 17, thereby improving the electron movement efficiency and improving the measurement accuracy and sensitivity of the infrared temperature sensor 10.

[0054] In a second aspect, the present application also provides a method for preparing an infrared temperature sensor, such as Figure 3 As shown, Figure 3 This is a flow chart of a method for preparing an infrared temperature sensor provided in an embodiment of the present application. Figure 4 to Figure 12 A diagram of the steps for preparing an infrared temperature sensor provided in an embodiment of the present application.

[0055] The preparation method comprises the following steps S10 to S20: Step S10: Figure 4 As shown, a substrate 11 is provided, and the substrate 11 includes a first surface P1 and a second surface P2 opposite to each other.

[0056] Step S20: Figure 5~Figure 9 As shown, a stacked channel layer 12, a barrier layer 13, a first electrode 14, an absorbing medium layer 15 and an absorbing resonance layer 16 are sequentially formed on the first surface P1, and an outer contour of an orthographic projection of the absorbing medium layer 15 on the first surface P1 at least partially exceeds an outer contour of an orthographic projection of the absorbing resonance layer 16 on the first surface P1.

[0057] For example, Figure 5 As shown, the material of the substrate 10 includes at least one of silicon or silicon carbide. In the process of forming the stacked structure, in order to avoid lattice mismatch and dislocation, a buffer layer 111 is further provided between the substrate 11 and the channel layer 12. For example, the materials of the buffer layer 111, the channel layer 12 and the barrier layer 13 all include gallium nitride. Among them, the barrier layer 13 can be etched by an inductively coupled plasma etching process to form a desired morphology of the gallium nitride mesa, and the process can more accurately control the etching depth and achieve a more ideal etching effect.

[0058] Afterwards, if Figure 6 As shown, a first electrode 14 is formed. The first electrode 14 is made of metal material, and the material type includes but is not limited to at least one of gold, aluminum, platinum, molybdenum, etc., and the thickness ranges from 50nm to 1000nm.

[0059] Then, if Figure 7 As shown, a plasma enhanced chemical vapor deposition process is used to form a passivation layer 141, and the passivation layer 141 is etched to form a first opening V1 and a second opening V2 exposing the first electrode 14. The material of the passivation layer 141 includes but is not limited to at least one of silicon nitride, silicon dioxide, aluminum oxide, etc., and the thickness of the passivation layer 141 ranges from 100nm to 500nm. The portion of the first electrode 14 exposed by the first opening V1 is used to subsequently form a metamaterial infrared absorber, and the portion of the first electrode 14 exposed by the second opening V2 can be used to be electrically connected to an external circuit.

[0060] The passivation layer 141 can be used to protect the first electrode 14 , and the thermal conductivity of the material of the passivation layer 141 is slightly worse than that of the first electrode 14 . The provision of the passivation layer 141 is also beneficial to reducing heat loss.

[0061] Afterwards, if Figure 8 As shown, an absorbing medium layer 15 is formed. The absorbing medium layer 15 contacts the first electrode 14 through the first opening V1 and has a thickness of 100 nm to 2000 nm. The material of the absorbing medium layer 15 may include but is not limited to at least one of silicon dioxide, silicon nitride, aluminum oxide, and the like.

[0062] Then, if Fig. 9 As shown, the wave absorbing resonance layer 16 is formed by electron beam evaporation or magnetron sputtering, and its material includes at least one of gold, silver, aluminum, copper, platinum, palladium or titanium. The morphology, size parameters and quantity of the wave absorbing resonance layer 16 can be reasonably designed according to the target band.

[0063] In some embodiments, after the wave absorbing resonance layer is formed, the preparation method further includes steps S21 and S22: Step S21: Fig.10 As shown, the channel layer 12 is etched to form a hollow portion L0 exposing the substrate 11 , and the orthographic projection of the hollow portion L0 on the first surface P1 surrounds the orthographic projection of the barrier layer 13 on the first surface P1 .

[0064] For example, when a buffer layer 111 is disposed between the channel layer 12 and the substrate 11, the channel layer 12 and the buffer layer 111 are etched by an inductively coupled plasma etching process to expose the first surface P1 of the substrate 11, and the hollowed-out area after etching is the hollowed-out portion L0.

[0065] Step S22: Fig.11 As shown, the substrate 11 is etched to form a cavity K0 communicating with the hollow portion L0.

[0066] For example, deep silicon etching is performed from the second surface P2 of the substrate 11 , and the etching thickness is the thickness of the substrate 11 . The cavity K0 formed by etching the substrate 11 is connected to the hollow portion L0 .

[0067] In the embodiment of the present application, the stacked structure formed by the channel layer 12, the barrier layer 13, the first electrode 14, the absorbing medium layer 15 and the absorbing resonance layer 16, the portion of which surrounded by the cavity K0 and the hollow portion L0 forms a structure similar to a suspended island. The arrangement of the cavity K0 and the hollow portion L0 is conducive to retaining as much temperature as possible in the suspended island structure.

[0068] Step S30: Fig.12 As shown, a second electrode 17 is formed on the second surface P2 , and the second electrode 17 penetrates the substrate 11 and is electrically connected to the channel layer 12 .

[0069] Exemplarily, in some embodiments, forming the second electrode 17 includes forming the second electrode 17 on the inner wall of the cavity K0, and the second electrode 17 is electrically connected to the channel layer 12 via the cavity K0. The thickness of the second electrode 17 is 20nm-1000nm, and the material may include at least one of gold, titanium, aluminum, platinum, etc.

[0070] At this point, the infrared temperature sensor 10 is completed.

[0071] The above-mentioned preparation method is relatively simple and has low process cost. In the prepared infrared temperature sensor 10, the first electrode 14, the absorbing medium layer 15 and the absorbing resonance layer 16 can form a metamaterial infrared absorber. When the infrared wave radiates into the metamaterial infrared absorber, the absorbing resonance layer 16 resonates. During the resonance, the photon energy of the infrared wave is converted into heat energy. In the corresponding band, the metamaterial infrared absorber can perfectly absorb the infrared wave, so that the temperature of the infrared temperature sensor 10 rises rapidly.

[0072] In addition, by utilizing the pyroelectric properties and electrostrictive effect of the channel layer 12 and the barrier layer 13, when the temperature changes, the self-polarization effect of the heterostructure formed by the channel layer 12 and the barrier layer 13 causes the electrons in the material to move in a direction perpendicular to the surface of the material, thereby generating polarized surface charges. The surface charges are discharged through the first electrode 14 and the second electrode 17 to form a current, and the temperature is detected by collecting the current size.

[0073] Since the metamaterial infrared absorber can perfectly absorb infrared waves, its absorption efficiency of infrared waves is greater than that of traditional materials. Compared with related technologies, under the same temperature change, the temperature rise of the infrared temperature sensor 10 provided in the embodiment of the present application is more obvious, which can form a larger current, thereby making the infrared temperature sensor 10 have a higher sensitivity.

[0074] Moreover, in some embodiments, by forming the hollow portion L0 and the cavity K0, the conduction and heat dissipation of heat in the solid can be reduced, which is beneficial for retaining the temperature increased by the metamaterial infrared absorber as much as possible in the suspended island structure part, thereby making the self-polarization effect of the heterogeneous structure more obvious, which is beneficial for forming a larger current and further improving the sensitivity of the external temperature sensor 10.

[0075] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that a person skilled in the art can think of within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. An infrared temperature sensor, characterized in that: include: a substrate comprising opposing first and second surfaces; A channel layer, a barrier layer, a first electrode, an absorbing medium layer and an absorbing resonance layer are sequentially stacked on the first surface, wherein an outer contour of an orthographic projection of the absorbing medium layer on the first surface at least partially exceeds an outer contour of an orthographic projection of the absorbing resonance layer on the first surface; The second electrode is disposed on the second surface, and the second electrode penetrates the substrate and is electrically connected to the channel layer.

2. The infrared temperature sensor according to claim 1, characterized in that: The infrared temperature sensor comprises a plurality of the wave absorbing resonance layers, and the orthographic projections of the plurality of the wave absorbing resonance layers on the first surface are located within the range of the orthographic projections of the wave absorbing medium layer on the first surface.

3. The infrared temperature sensor according to claim 1, characterized in that: The material of the channel layer includes at least one of gallium nitride, gallium arsenide or indium gallium arsenide, and the material of the barrier layer includes at least one of indium gallium nitride, aluminum gallium nitride, indium phosphide, aluminum gallium arsenide or indium aluminum arsenide.

4. The infrared temperature sensor according to claim 1, characterized in that: The infrared temperature sensor further includes a buffer layer disposed between the substrate and the channel layer, and the second electrode is electrically connected to the channel layer through the buffer layer.

5. The infrared temperature sensor according to claim 1, characterized in that: The material of the absorbing medium layer includes at least one of silicon oxide, silicon nitride or aluminum oxide.

6. The infrared temperature sensor according to claim 1, characterized in that: The material of the wave absorbing resonance layer includes at least one of gold, silver, aluminum, copper, platinum, palladium or titanium.

7. The infrared temperature sensor according to claim 1, characterized in that: The infrared temperature sensor further includes a hollow portion; The orthographic projection of the hollow portion on the first surface surrounds the orthographic projection of the barrier layer on the first surface.

8. The infrared temperature sensor according to claim 1, characterized in that: The substrate comprises a through cavity, and the second electrode is arranged on an inner wall of the cavity; The second electrode is electrically connected to the channel layer through the cavity.

9. A method for preparing an infrared temperature sensor, characterized in that: include: providing a substrate comprising a first surface and a second surface opposite to each other; A stacked channel layer, a barrier layer, a first electrode, an absorbing medium layer and an absorbing resonance layer are sequentially formed on the first surface, wherein an outer contour of an orthographic projection of the absorbing medium layer on the first surface at least partially exceeds an outer contour of an orthographic projection of the absorbing resonance layer on the first surface; A second electrode is formed on the second surface, and the second electrode penetrates the substrate and is electrically connected to the channel layer.

10. The preparation method according to claim 9, characterized in that: After forming the wave absorbing resonance layer and before forming the second electrode, the preparation method further includes: The channel layer is etched to form a hollow portion exposing the substrate; the orthographic projection of the hollow portion on the first surface surrounds the orthographic projection of the barrier layer on the first surface; Etching the substrate to form a cavity communicating with the hollow portion; The second electrode is formed, comprising: The second electrode is formed on the inner wall of the cavity, and the second electrode is electrically connected to the channel layer through the cavity.

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