Manufacturing method of high-performance blackbody radiation layer

Abstract

The invention relates to a method for manufacturing a high-performance blackbody radiation layer, which comprises the following steps of: firstly, providing a growth substrate for growing the blackbody radiation layer; then, photoetching patterning is carried out on the substrate; then, plasma etching is carried out on the substrate containing the photoetching pattern; and finally, carrying out high-temperature annealing treatment on the substrate. The MEMS infrared light source is simple in process flow, compatible in preparation process and semiconductor process, suitable for process integration and mass production, and beneficial for reducing the cost of the MEMS infrared light source, the black body radiation layer is obtained by carrying out plasma etching on the photoresist and then carrying out high-temperature annealing, the patterning of the black body radiation layer is equal to the patterning of the photoresist, and the manufacturing cost of the black body radiation layer is reduced. Compared with other types of black body radiation layers, the black body radiation layer has the advantage of being easy to manufacture tiny patterns.

Description

Technical Field

[0001] The present invention relates to the technical field of infrared processing, and particularly refers to a method for manufacturing a high-performance blackbody radiation layer. Background Art

[0002] The NDIR infrared gas sensor realizes the detection of gas types and concentrations by measuring the absorption of infrared light of a specific wavelength by the gas, and is an accurate and reliable gas concentration measurement element, which has important applications in the fields of medicine, industry, etc. The MEMS infrared light source is one of the core components of the NDIR infrared gas sensor, which greatly affects the performance of the infrared gas sensor.

[0003] The MEMS infrared light source is an element based on semiconductor processing technology, and is usually a multi-layer structure composed of a substrate, a support layer, a heating resistance layer, a blackbody radiation layer, etc. Among them, structures such as the substrate, the support layer, and the heating resistance layer can be processed by conventional semiconductor processes with relatively low difficulty, while the processing technology of the blackbody radiation layer is a special process, which is the most critical process in the processing of the MEMS infrared light source, affecting the performance and cost of the MEMS infrared light source, and is the difficulty in the entire processing of the MEMS infrared light source;

[0004] For example, a self-supporting MEMS infrared light source and its preparation method disclosed in the prior art 202210505995.1 deposit a blackbody radiation layer in the middle area of the heating resistance by electroplating, and there are the following problems:

[0005] 1. Complex process:

[0006] The electroplating method usually requires complex equipment and operation processes, including the preparation of electroplating solutions, the control of electroplating conditions, etc., which increases the complexity and cost of preparation.

[0007] 2. Difficult to pattern:

[0008] The electroplating method has difficulties in achieving precise patterning of the blackbody radiation layer. Since electroplating is a process in a liquid environment, it is difficult to precisely control the edges and shapes of the patterns, which may lead to irregular or blurred patterns.

[0009] 3. The performance of the fabricated blackbody radiation layer is not good:

[0010] The blackbody radiation layer prepared by the electroplating method may have problems in terms of uniformity, adhesion, and thermal stability, etc.; for example, the thickness of the electroplated layer may be uneven, resulting in inconsistent radiation performance; the adhesion between the electroplated layer and the heating resistance may be insufficient, affecting the reliability and life of the device; the electroplated layer may deform or peel off at high temperatures, reducing the thermal stability of the device. Summary of the Invention

[0011] The object of the present invention is to provide a method for fabricating a high-performance blackbody radiation layer to overcome the deficiencies of the prior art, so as to improve the performance of MEMS infrared light sources and reduce the cost of MEMS infrared light sources.

[0012] To achieve the above object, the technical solution adopted by the present invention is: A method for fabricating a high-performance blackbody radiation layer, comprising the following steps:

[0013] S1. Provide a growth substrate for the growth of the blackbody radiation layer;

[0014] S2. Perform photolithographic patterning on the substrate;

[0015] S3. Perform plasma etching on the substrate including the photolithographic pattern;

[0016] S4. Perform high-temperature annealing treatment on the substrate.

[0017] Preferably, in step S1, the substrate is silicon or a silicon substrate including a metal resistance pattern.

[0018] Preferably, in step S2, the thickness range of the photoresist is 0.1 - 10 um.

[0019] Preferably, in step S3, the substrate including the photolithographic pattern is subjected to full-surface plasma etching.

[0020] Preferably, in step S3, the gas used in the plasma etching process is one or more of SF6, CF4, Ar, etc.

[0021] Preferably, in step S4, the temperature range of the annealing process is 400°C - 1000°C, and the time range of the annealing process is 1 - 8 h.

[0022] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0023] 1. The method for fabricating a high-performance blackbody radiation layer provided by the present invention has a simple process flow, and the preparation process is compatible with semiconductor processes, which is suitable for process integration and mass production, and is beneficial to reducing the cost of MEMS infrared light sources;

[0024] 2. In the method for fabricating a high-performance blackbody radiation layer provided by the present invention, the blackbody radiation layer is obtained by first performing plasma etching on the photoresist and then performing high-temperature annealing. The patterning of the blackbody radiation layer is equivalent to the patterning of the photoresist. Therefore, the blackbody radiation layer is easy to form into a micro pattern, and has the advantage of being easy to fabricate a micro pattern compared with other types of blackbody radiation layers;

[0025] 3. The blackbody radiation layer fabricated by the present invention has excellent performance while having high reliability. It has an ultra-high emissivity in the range of 1 - 20 μm, and its radiation spectrum is very close to that of a blackbody. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The technical solution of the present invention will be further described below with reference to the drawings:

[0027] Att Figure 1 is a flowchart of the manufacturing method of the high-performance blackbody radiation layer according to the present invention;

[0028] Att Figure 2 is a schematic cross-sectional view of the initial growth substrate in the manufacturing method of the present invention;

[0029] Att Figure 3 is a schematic cross-sectional view after photolithographic patterning in the manufacturing method of the present invention;

[0030] Att Figure 4 is a schematic cross-sectional view after plasma etching in the manufacturing method of the present invention;

[0031] Att Figure 5 is a schematic cross-sectional view after high-temperature annealing in the manufacturing method of the present invention.

[0032] Wherein: 1. Semiconductor substrate; 2. Metal heating layer; 3. Support layer; 4. Cavity; 5. Photoresist; 6. Ashing photoresist; 7. Blackbody radiation layer. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] The present invention will be further described in detail below with reference to the drawings and specific embodiments.

[0034] Att Figure 1 is the manufacturing method of the high-performance blackbody radiation layer according to the present invention, comprising the following steps:

[0035] S1. Provide a growth substrate for the growth of the blackbody radiation layer;

[0036] S2. Perform photolithographic patterning on the substrate;

[0037] S3. Perform plasma etching on the substrate including the photolithographic pattern;

[0038] S4. Perform high-temperature annealing treatment on the substrate.

[0039] Figures 2 to 5 is a schematic cross-sectional view of the manufacturing process of the high-performance blackbody radiation layer disclosed in the embodiment of the present invention.

[0040] In this embodiment, the initial substrate includes a semiconductor substrate 1, a metal heating layer 2, a support layer 3, and a cavity 4, as Figure 2As shown, the initial structure of the embodiment is a typical MEMS infrared light source structure. After the metal heating layer 2 is heated by energization, it generates infrared radiation to the outside. The support layer 3 is used for the stable support of the structure, and the cavity 4 is to reduce heat loss.

[0041] In this embodiment, the schematic cross-sectional view after photolithographic patterning is as Figure 3 . The remaining photoresist pattern is located in the middle radiation area, and the thickness range of the photoresist made is 0.1 - 10 μm.

[0042] In this embodiment, the schematic cross-sectional view after photoresist ashing is as Figure 4 . The substrate containing the photolithographic pattern is subjected to full-surface plasma etching.

[0043] In this embodiment, the gas used in the photoresist ashing plasma etching process is one or more of SF6, CF4, Ar, etc.; after the photoresist undergoes this process step, its pattern color will become darker and the surface will become relatively rough.

[0044] In this embodiment, the schematic cross-sectional view after high-temperature annealing is as Figure 5 . The temperature range of the high-temperature annealing process is 400°C - 1000°C, and the time range of the annealing process is 1 - 8 h; the surface of the blackbody radiation layer obtained after high-temperature annealing is dark black and has an ultra-high emissivity in the wide spectral range.

[0045] The above are only specific application examples of the present invention and do not constitute any limitation to the protection scope of the present invention. Any technical solutions formed by equivalent transformation or equivalent substitution fall within the scope of the protection of the rights of the present invention.

Claims

1. A method for manufacturing a high-performance blackbody radiation layer, characterized in that: The following steps are involved: S1. providing a growth substrate for growing a black body radiation layer; S2, performing photolithography patterning on the substrate; S3, performing plasma etching on the substrate including the photolithography pattern; S4, performing high temperature annealing treatment on the substrate.

2. The method for manufacturing a high-performance blackbody radiation layer according to claim 1, characterized in that: In step S1, the substrate is silicon or a silicon substrate including a metal resistor pattern.

3. The method for manufacturing a high-performance blackbody radiation layer according to claim 1, characterized in that: In step S2, the photoresist has a thickness ranging from 0.1 to 10 um.

4. The method for manufacturing a high-performance blackbody radiation layer according to claim 1, characterized in that: In step S3, the substrate including the photolithography pattern is subjected to full-surface plasma etching.

5. The method for manufacturing a high-performance blackbody radiation layer according to claim 4, characterized in that: In step S3, the gas used in the plasma etching process is one or more of SF6, CF4, Ar, etc.

6. The method for manufacturing a high-performance blackbody radiation layer according to claim 1, characterized in that: In step S4, the temperature range of the annealing process is 400° C.-1000° C., and the time range of the annealing process is 1-8 hours.

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