An absorber and a manufacturing method thereof

Abstract

The present invention provides an absorber and a manufacturing method thereof. The method includes: spin-coating a first layer of photoresist on a substrate and / or a sensor; performing secondary exposure and development on the first layer of photoresist to obtain a preset concavo-convex strengthening structure; depositing absorber material on the preset concavo-convex strengthening structure to obtain a deposited concavo-convex strengthening structure; spin-coating a second layer of photoresist on the deposited concavo-convex strengthening structure; and etching the absorber pattern using the second layer of photoresist as a mask to obtain the absorber. By using photolithography technology to manufacture the absorber, when detecting a specific signal, the present invention can quickly transfer heat to the temperature sensor. Moreover, since the surface of the absorber cap has a concavo-convex strengthening structure pattern, while ensuring relatively high mechanical strength of the absorber, the absorber has a small heat capacity and high signal detection ability. In addition, the weak connection between the absorber and the substrate using support feet also ensures the data acquisition time.

Description

Technical Field

[0001] The present invention relates to the technical field of thermal detectors, and more particularly, to an absorber and a method for manufacturing the same. Background Art

[0002] A microcalorimeter is a type of thermal detector that increases in temperature after absorbing the energy of rays. It generally consists of an absorber for absorbing rays and a sensor. The resistance of the sensor changes with temperature. By measuring the change in its resistance, high-sensitivity detection of X-rays and γ-rays can be achieved, even single-photon detection. It is widely used in fields such as astronomy, quantum information, biological detection, and materials science.

[0003] The energy resolution (ΔE) of a microcalorimeter is restricted by the heat capacity (C). The heat capacity C is determined by the sensor and the absorber on it. The absorber is used to convert the received ray energy into a temperature rise. This means that the heat capacity of the absorber needs to be as small as possible to ensure high energy resolution of the microcalorimeter. Due to the limitation of the signal readout speed, a weak connection is required between the absorber and the sensor to ensure the time for thermal equilibrium for measurement.

[0004] In addition, high thermal conductivity is also an important requirement for the absorber. The absorber needs to quickly reach thermal equilibrium after absorbing rays to ensure that the sensor measures a stable temperature rise.

[0005] Based on the above requirements for the absorber, a "suspended" structure is generally adopted. Currently, the thickness of the absorber of a microcalorimeter with a "suspended" structure is generally greater than 1.8 microns, and the side length is generally 120 - 625 microns, and its energy resolution is 0.6 eV. It can be seen that the existing absorber has the defect of low energy resolution. Summary of the Invention

[0006] To solve the above problems, an object of an embodiment of the present invention is to provide an absorber and a method for manufacturing the same.

[0007] An absorber includes:

[0008] An absorber cap;

[0009] Support legs, the support legs being connected to the absorber cap; the support legs and the absorber cap are of an integral structure.

[0010] Preferably, the absorber cap is of a plate-like structure; the thickness of the absorber cap is 200 - 20000 nanometers.

[0011] Preferably, the structure of the support legs is cylindrical; the diameter of the support legs is 3 - 10 microns.

[0012] Preferably, one end of the support leg is connected to the absorber cap, and the other end of the support leg is connected to the substrate and / or the sensor.

[0013] Preferably, the surface of the absorber cap has concave-convex strengthening structural patterns; the concave-convex strengthening structural patterns include, but are not limited to, one or more of transverse and longitudinal beam patterns, multi-D character patterns, lentil patterns, and T-shaped patterns.

[0014] The present invention also provides a method for manufacturing an absorber, which is applied to the absorber and is characterized by including:

[0015] Step 1: Spin-coat a first layer of photoresist on the substrate and / or the sensor;

[0016] Step 2: Expose the first layer of photoresist to obtain a support leg pattern;

[0017] Step 3: Perform secondary exposure and development on the first layer of photoresist to obtain a preset concave-convex strengthening structure;

[0018] Step 4: Deposit absorber material on the preset concave-convex strengthening structure to obtain a deposited concave-convex strengthening structure;

[0019] Step 5: Spin-coat a second layer of photoresist on the deposited concave-convex strengthening structure;

[0020] Step 6: Expose and develop the second layer of photoresist to obtain an absorber pattern;

[0021] Step 7: Etch the absorber pattern using the second layer of photoresist as a mask to obtain an absorber.

[0022] Preferably, after Step 3: Perform secondary exposure and development on the first layer of photoresist to obtain a preset concave-convex strengthening structure, the method further includes:

[0023] Bake the preset concave-convex strengthening structure and chamfer the edges of the preset concave-convex strengthening structure.

[0024] Preferably, Step 4: Deposit absorber material on the preset concave-convex strengthening structure to obtain a deposited concave-convex strengthening structure, includes:

[0025] Deposit a first layer of absorber material on the preset concave-convex strengthening structure to obtain a deposited concave-convex strengthening structure; the first layer of absorber material includes gold or copper.

[0026] Preferably, Step 4: Deposit absorber material on the preset concave-convex strengthening structure to obtain a deposited concave-convex strengthening structure, includes:

[0027] Deposit a first absorber material layer and a second absorber material layer in sequence on the preset concavo-convex strengthening structure to obtain a concavo-convex strengthening structure with deposition completed; the first absorber material layer includes gold or copper; the second absorber material layer includes bismuth.

[0028] Preferably, step 7: etching the absorber pattern using the second photoresist as a mask to obtain an absorber, includes:

[0029] Step 7.1: etching the absorber pattern using an argon ion beam or an etching solution to obtain an etched absorber pattern;

[0030] Step 7.2: soaking the etched absorber pattern with acetone to remove the photoresist on the etched absorber pattern to obtain an absorber.

[0031] Step 7.3: drying the absorber after removing the photoresist by soaking with acetone in step 7.2 using the critical point drying method.

[0032] The beneficial effects of an absorber and its manufacturing method provided by the present invention are as follows: Compared with the prior art, a manufacturing method of an absorber of the present invention includes spin-coating a first photoresist on a substrate or / and a sensor; exposing the first photoresist to obtain a support foot pattern; performing secondary exposure and development on the first photoresist to obtain a preset concavo-convex strengthening structure; depositing an absorber material on the preset concavo-convex strengthening structure to obtain a concavo-convex strengthening structure with deposition completed; spin-coating a second photoresist on the concavo-convex strengthening structure with deposition completed; exposing and developing the second photoresist to obtain an absorber pattern; etching the absorber pattern using the second photoresist as a mask to obtain an absorber. By using photolithography technology to manufacture the absorber, when detecting a specific signal, heat can be quickly transferred to the temperature sensor, and since the surface of the absorber cap has a concavo-convex strengthening structure pattern, while ensuring the relatively high mechanical strength of the absorber, the thickness of the manufactured absorber can be very thin, making the absorber have a small heat capacity and high signal detection ability. In addition, the weak connection between the absorber and the substrate using support feet also ensures the data acquisition time.

[0033] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following specifically gives preferred embodiments and, in conjunction with the accompanying drawings, makes detailed descriptions as follows. Description of the Drawings

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0035] Figure 1 Shows a schematic cross-sectional view of the absorber provided by an embodiment of the present invention;

[0036] Figure 2 Shows several pattern schematic diagrams of the concave-convex strengthening structure provided by an embodiment of the present invention; wherein, A represents a planar structure pattern, B represents a multi-character structure pattern, C represents a horizontal and vertical beam pattern, and D represents a lentil pattern;

[0037] Figure 3 Shows the graphic and layout schematic diagrams of the support feet provided by an embodiment of the present invention; wherein, a represents the triangular layout of the first support feet, b represents the triangular layout of the second support feet, c represents the quadrilateral layout of the first support feet, d represents the quadrilateral layout of the second support feet, e represents the multi-support layout of the first support feet, and f represents the multi-support layout of the second support feet.

[0038] The reference numerals in the figure respectively represent:

[0039] 101, substrate or sensor; 102, absorber cap; 103, chamfer of support feet; 104, support feet; 105, absorber cap; 106, chamfer of concave-convex strengthening structure; 107, concave-convex strengthening structure; 108, absorber cap. Detailed implementation manners

[0040] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0041] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality" means two or more, unless otherwise specifically defined.

[0042] In the present invention, unless otherwise clearly defined and limited, terms such as "installation", "connection", "linkage", "fixation", etc. shall be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0043] To solve the above problems, an object of an embodiment of the present invention is to provide an absorber and a manufacturing method thereof.

[0044] Please refer to Figures 1 - 3 , an absorber, comprising: an absorber cap and support legs; the surface of the absorber cap is provided with a concavo-convex strengthening structure pattern; the concavo-convex strengthening structure pattern includes but is not limited to any one or more of a crosswise and longitudinal beam pattern, a multi-D character structure pattern, a lentil pattern, a T-shaped pattern, and a planar structure pattern; one end of the support leg is connected to the absorber cap, and the other end of the support leg is connected to a substrate and / or a sensor, and the layout of the support leg and the substrate is as Figure 3 shown.

[0045] In the present invention, the support legs of the absorber are cylinders with a diameter of 3 to 10 micrometers, and the material can be the same as or different from that of the absorber cap, that is, it can be hollow or solid. The support legs and the absorber cap adopt a one-step forming technique. The sensor on the substrate is a temperature sensor, and its performance changes with temperature, including semiconductor sensors and superconducting transition edge sensors, etc. A part of the support legs of the absorber is connected to the substrate, and a part is connected to the temperature sensor. The part of the support legs connected to the sensor is used for support and heat transfer, and the part connected to the substrate is used for support.

[0046] As another specific embodiment of the present invention, the absorber cap includes: an absorber cap 102; support legs 104, one end of the support legs 104 is connected to one end of the absorber cap 102; an absorber cap 105, one end of the absorber cap 105 is connected to the other end of the support legs 104; a concavo-convex strengthening structure 107, one end of the concavo-convex strengthening structure 107 is connected to the other end of the absorber cap 105; an absorber cap 108, one end of the absorber cap 108 is connected to the other end of the concavo-convex strengthening structure 107.

[0047] As another specific embodiment of the present invention, the absorber cap is in a plate-like structure, with a size in the plane of 100 to 3000 micrometers and a thickness of 200 to 20000 nanometers, and has a concavo-convex strengthening structure pattern in the plane.

[0048] The present invention also provides a manufacturing method of an absorber. The method is applied to the absorber and includes:

[0049] Step 1: Spin-coat the first layer of photoresist on the substrate and / or the sensor;

[0050] Step 2: Expose the first layer of photoresist to obtain the support leg pattern;

[0051] Step 3: Perform secondary exposure and development on the first layer of photoresist to obtain a preset concavo-convex strengthening structure;

[0052] Step 4: Deposit absorber material on the preset concavo-convex strengthening structure to obtain a deposited concavo-convex strengthening structure;

[0053] Specifically, deposit the first layer of absorber material on the preset concavo-convex strengthening structure to obtain a deposited concavo-convex strengthening structure; the first layer of absorber material includes gold or copper.

[0054] In the present invention, two layers of absorber material can also be deposited according to actual needs. Further, deposit the first layer of absorber material and the second layer of absorber material on the preset concavo-convex strengthening structure in sequence to obtain a deposited concavo-convex strengthening structure; the first layer of absorber material includes gold or copper; the second layer of absorber material includes bismuth.

[0055] Step 5: Spin-coat the second layer of photoresist on the deposited concavo-convex strengthening structure;

[0056] Step 6: Expose and develop the second layer of photoresist to obtain the absorber pattern;

[0057] Step 7: Etch the absorber pattern using the second layer of photoresist as a mask to obtain the absorber;

[0058] Among them, Step 7 specifically includes:

[0059] Step 7.1: Etch the absorber pattern using an argon ion beam or an etching solution that can dissolve the first layer of absorber material and the second layer of absorber material to obtain an etched complete absorber pattern;

[0060] Step 7.2: Soak with acetone to remove the photoresist on the etched complete absorber pattern to obtain the absorber.

[0061] Step 7.3: Dry the absorber after soaking with acetone in Step 7.2 using the critical point drying method. The absorber includes an absorber cap, and the surface of the absorber cap is provided with concavo-convex strengthening structure patterns; the concavo-convex strengthening structure patterns include, but are not limited to, horizontal and vertical beam patterns, multi-D character structure patterns, lentil patterns, and T-shaped patterns; a substrate, the substrate is not in contact with the absorber cap; support legs, one end of the support legs is connected to the absorber cap, and the other end of the support legs is in contact with the substrate.

[0062] After Step 3: Perform secondary exposure and development on the first layer of photoresist to obtain a preset concavo-convex strengthening structure, it further includes:

[0063] Bake the preset concave-convex strengthening structure and chamfer the edges of the preset concave-convex strengthening structure.

[0064] The following further describes the method for manufacturing the absorber in the present invention with reference to specific embodiments:

[0065] In the present invention, microfabrication technology is adopted for manufacturing the absorber. First, a layer of photoresist is spin-coated on the temperature sensor and the substrate, and photolithography technology is used to define the pattern of the support feet.

[0066] Furthermore, for the concave-convex strengthening structure of the absorber, double-exposure technology is used. After spin-coating a layer of photoresist on the sensor and the substrate and exposing to define the pattern of the support feet, double-dose reduction exposure is used to define a specific concave-convex strengthening structure, and then development is carried out uniformly. The support foot structure of the photoresist penetrates the photoresist, and the concave-convex strengthening structure only has a certain depth from the upper surface of the photoresist downward and does not completely penetrate the photoresist.

[0067] The spin-coated photoresist is exposed and developed in sequence and then baked at a high temperature of 100-160 °C to chamfer the steep pattern edges smoothly.

[0068] The patterned photoresist on the substrate is briefly treated with oxygen plasma at a certain power, and then the first layer of absorber material is deposited as soon as possible. And it can be selected whether to deposit the second layer of absorber material immediately according to needs. The deposition method of the second layer of absorber material is physical deposition or electroplating; specifically, first deposit a certain thickness of the first layer of absorber material and then deposit the second layer of absorber material to the target thickness. The first layer of absorber material is gold or copper, and the second layer of absorber material is bismuth.

[0069] For the concave-convex strengthening structure after depositing the absorber material, spin-coat the second layer of photoresist on its surface, and expose and develop to define the absorber pattern. Using this layer of photoresist as a mask, use an argon ion beam or an etching solution that can dissolve the first layer of absorber material and the second layer of absorber material to etch away the excess absorber material, and soak it in acetone to remove the photoresist on it. Use the critical point drying technology to dry under the condition of zero liquid surface tension to complete the preparation of the absorber.

[0070] The absorber prepared by the present invention has few support feet, a thin thickness (small heat capacity), and high energy resolution, and can meet the requirements for absorbers in different application fields.

[0071] An absorber and a manufacturing method thereof provided by the present invention. A manufacturing method of an absorber of the present invention includes spin-coating a first layer of photoresist on a substrate or / and a sensor; exposing the first layer of photoresist to obtain a support leg pattern; performing secondary exposure and development on the first layer of photoresist to obtain a preset concavo-convex strengthening structure; depositing an absorber material on the preset concavo-convex strengthening structure to obtain a deposited concavo-convex strengthening structure; spin-coating a second layer of photoresist on the deposited concavo-convex strengthening structure; exposing and developing the second layer of photoresist to obtain an absorber pattern; etching the absorber pattern with the second layer of photoresist as a mask to obtain an absorber. By using photolithography technology to manufacture the absorber, when detecting a specific signal, heat can be quickly transferred to the temperature sensor. Moreover, since the surface of the absorber cap has a concavo-convex strengthening structure pattern, while ensuring the high mechanical strength of the absorber, the thickness of the manufactured absorber can be very thin, making the absorber have a small heat capacity and high signal detection ability. In addition, the weak connection between the absorber and the substrate using support legs also ensures the data acquisition time.

[0072] As described above, the above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of technical solutions of changes or substitutions, and all of them should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. An absorber, characterized in that, Comprising: Absorber cap; Supporting feet, which are connected to the absorber cap; the supporting feet and the absorber cap are of an integral structure; The surface of the absorber cap is provided with concave-convex strengthening structure patterns; the concave-convex strengthening structure patterns include, but are not limited to, one or several of cross and longitudinal beam patterns, multi-D character structure patterns, lentil patterns and T-shaped patterns.

2. The absorber according to claim 1, wherein, The absorber cap is of a plate structure; the thickness of the absorber cap is 200 - 20000 nanometers.

3. An absorber according to claim 1, characterized in that, The structure of the supporting feet is cylindrical; the diameter of the supporting feet is 3 - 10 micrometers.

4. An absorber according to claim 1, characterized in that, One end of the supporting feet is connected to the absorber cap, and the other end of the supporting feet is connected to the substrate and / or the sensor.

5. A method for manufacturing an absorber, the method being applied to the absorber according to any one of claims 1-4, characterized in that, Comprising: Step 1: Spin-coat a first layer of photoresist on the substrate and / or the sensor; Step 2: Expose the first layer of photoresist to obtain a supporting foot pattern; Step 3: Perform secondary exposure and development on the first layer of photoresist to obtain a preset concave-convex strengthening structure; Step 4: Deposit absorber material on the preset concave-convex strengthening structure to obtain a deposited complete concave-convex strengthening structure; Step 5: Spin-coat a second layer of photoresist on the deposited complete concave-convex strengthening structure; Step 6: Expose and develop the second layer of photoresist to obtain an absorber pattern; Step 7: Etch the absorber pattern using the second layer of photoresist as a mask to obtain an absorber.

6. The method for manufacturing an absorber according to claim 5, wherein, In the said Step 3: After performing secondary exposure and development on the first layer of photoresist to obtain a preset concave-convex strengthening structure, it further includes: Bake the preset concave-convex strengthening structure and chamfer the edges and corners on the preset concave-convex strengthening structure.

7. A method for manufacturing an absorber according to claim 5, characterized in that, The said Step 4: Deposit absorber material on the preset concave-convex strengthening structure to obtain a deposited complete concave-convex strengthening structure, including: Deposit a first layer of absorber material on the preset concave-convex strengthening structure to obtain a deposited complete concave-convex strengthening structure; the first layer of absorber material includes gold or copper.

8. A method for manufacturing an absorber according to claim 5, characterized in that, The said Step 4: Deposit absorber material on the preset concave-convex strengthening structure to obtain a deposited complete concave-convex strengthening structure, including: Deposit a first layer of absorber material and a second layer of absorber material in sequence on the preset concave-convex strengthening structure to obtain a deposited complete concave-convex strengthening structure; the first layer of absorber material includes gold or copper; the second layer of absorber material includes bismuth.

9. A method for manufacturing an absorber according to claim 5, characterized in that, The said Step 7: Etch the absorber pattern using the second layer of photoresist as a mask to obtain an absorber, including: Step 7.1: Etch the absorber pattern using an argon ion beam or an etching solution to obtain an etched complete absorber pattern; Step 7.2: Soak with acetone to remove the photoresist on the etched complete absorber pattern to obtain an absorber; Step 7.3: Dry the absorber after removing the photoresist by soaking with acetone in Step 7.2 using the critical point drying method.

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