Pixel sounding unit and manufacturing method thereof, digital sounding chip

Abstract

The application discloses a pixel sound unit, a manufacturing method thereof and a digital sound chip, and relates to the technical field of microelectronic manufacturing, and aims to solve the problems of poor safety and reliability of the pixel sound unit. The pixel sound unit comprises an electrode structure layer, a diaphragm, a support structure and an electrical isolation layer. The support structure is arranged between the electrode structure layer and the diaphragm, and the support structure comprises a plurality of support bodies which are distributed on the electrode structure layer at intervals. The electrical isolation layer is arranged on the electrode structure layer and the support structure in a laminated mode, and is used for electrically isolating the electrode structure layer and the diaphragm. The digital sound chip comprises the pixel sound unit disclosed in the technical solution, and the manufacturing method of the pixel sound unit comprises the pixel sound unit disclosed in the technical solution.

Description

Technical Field

[0001] This invention relates to the field of microelectronics manufacturing technology, and in particular to a pixel-based sound-generating unit and its manufacturing method, as well as a digital sound-generating chip. Background Technology

[0002] A loudspeaker is a transducer that converts electrical signals into sound signals. Loudspeakers are fundamental to the manufacture of audio equipment and active acoustic noise reduction devices; therefore, their performance has a crucial impact on the production of acoustic devices. MEMS loudspeakers (Micro-Electro-Mechanical Systems) offer advantages over traditional voice coil loudspeakers, including better consistency, lower power consumption, smaller size, and lower price.

[0003] Currently, commonly used MEMS loudspeakers consist of multiple pixel sound-generating units. Each pixel sound-generating unit includes an electrode layer and a diaphragm. When the loudspeaker is working, the diaphragm can vibrate up and down under the electrostatic force of the electrode layer to produce sound. However, when the diaphragm moves downward, it is easy to come into contact with the electrode layer below, affecting the safety and reliability of the pixel sound-generating unit. Summary of the Invention

[0004] The purpose of this invention is to provide a pixel-based sound-generating unit and its manufacturing method, as well as a digital sound-generating chip, to improve the safety and reliability of the pixel-based sound-generating unit.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a pixel-based sound-emitting unit, comprising an electrode structure layer and a diaphragm, and further comprising:

[0006] A support structure is disposed between the electrode structure layer and the diaphragm, and the support structure includes multiple supports spaced apart on the electrode structure layer;

[0007] An electrical isolation layer is stacked on the electrode structure layer and the support structure to electrically isolate the electrode structure layer and the diaphragm.

[0008] With the above technical solution, the electrode structure layer and the diaphragm are electrically isolated by an electrical isolation layer, which prevents the diaphragm from contacting the electrode structure layer during downward movement, thus improving the safety of the pixel sound generation unit. The support structure, located between the electrode structure layer and the diaphragm, supports the diaphragm during downward movement, preventing excessive downward amplitude and damage, thereby improving the reliability of the pixel sound generation unit. When the diaphragm is ultra-thin, it is prone to excessive amplitude and breakage during downward movement. The support structure and electrical isolation layer provide good support for the ultra-thin diaphragm, preventing breakage during downward movement and extending its service life. Simultaneously, the support structure and electrical isolation layer increase the distance between the diaphragm and the electrode structure layer, reducing the actual electric field strength at the support structure, thereby reducing the possibility of the support structure being broken down by the voltage between the diaphragm and the electrode structure layer, and further improving the circuit safety and reliability of the pixel sound generation unit.

[0009] In some possible implementations, the electrode structure layer includes a segmented annular groove that divides the electrode structure layer into an inner ring and an outer ring, with the inner ring electrically isolated from the outer ring. The support is located on the inner ring. This configuration electrically isolates the inner ring from the outer ring, further reducing the actual electric field strength at the support structure and improving the circuit safety and reliability of the pixel sound-generating unit.

[0010] In some possible implementations, the segmented ring groove is filled with an insulating structure. This configuration further isolates the inside and outside of the ring through electrical isolation, improving the circuit safety and reliability of the pixel sound-generating unit; filling the segmented ring groove with an insulating structure also enhances the overall stability of the pixel sound-generating unit.

[0011] In some possible implementations, the insulation structure and the electrical isolation layer are integrated into one structure. This configuration can further improve the overall stability of the pixel-based sound-generating unit.

[0012] In some possible implementations, the difference between the inner and outer diameters of the dividing ring groove is 0.5 μm to 2 μm. This setting optimizes the dimensions of the dividing ring groove and ensures electrical isolation between the inside and outside of the ring.

[0013] In some possible implementations, the support is a cylindrical structure, and the portion of the electrical isolation layer stacked on the support has rounded chamfers;

[0014] The diameter of the support cross-section is 1μm to 5μm, and the difference between the inner diameter of the dividing annular groove and the outer diameter of the support is 1μm to 3μm. This design prevents the diaphragm from being damaged when it comes into contact with the edges of the electrical isolation layer.

[0015] In some possible implementations, the support material is silicon dioxide or silicon nitride, and the height of the support is 150nm to 300nm;

[0016] And / or, the material of the electrical isolation layer is silicon nitride, and the thickness of the electrical isolation layer is 150nm to 500nm. This configuration ensures electrical isolation between the electrode structure layer and the diaphragm.

[0017] In some possible implementations, multiple supports are arranged in an array. This configuration, where the diaphragm is supported by multiple arrayed supports, can improve the reliability of the pixel-based sound-generating unit.

[0018] In a second aspect, the present invention also provides a digital sound chip, including a pixel sound unit as provided in any of the above solutions.

[0019] With the above technical solution, since the digital sound chip uses the pixel sound unit in this application, the security and reliability of the digital sound chip can be improved.

[0020] Thirdly, the present invention also provides a method for manufacturing a pixel sound-emitting unit, comprising the pixel sound-emitting unit as provided in any of the above embodiments, wherein the manufacturing method comprises:

[0021] Provide an electrode structure layer;

[0022] A first dielectric layer is deposited on the electrode structure layer;

[0023] The first dielectric layer is etched to form a support structure, which includes multiple supports spaced apart on the electrode structure layer.

[0024] The electrode structure layer is etched to form a segmented annular groove, which divides the electrode structure layer into an electrically isolated inner ring and an outer ring, with the support located inside the ring.

[0025] A second dielectric layer is deposited on the electrode structure layer and the first dielectric layer. The second dielectric layer is partially stacked on the electrode structure layer and the support structure to form an electrical isolation layer. The second dielectric layer is partially filled in the segmented ring groove to electrically isolate the inside and outside of the ring.

[0026] When the above technical solution is adopted, since the manufacturing method of the pixel sound unit uses the pixel sound unit of this application, the safety and reliability of the pixel sound unit can be improved. Attached Figure Description

[0027] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings:

[0028] Figure 1 This is a schematic diagram of the pixel sound-emitting unit after etching to form a support structure in this invention;

[0029] Figure 2 This is a schematic diagram of the pixel sound-emitting unit after etching to form the segmented annular groove in this invention;

[0030] Figure 3 This is a schematic diagram of the pixel sound-emitting unit after the second dielectric layer has been deposited in this invention;

[0031] Figure 4 This is a top view of the pixel sound-emitting unit after the second dielectric layer has been deposited in this invention.

[0032] Figure label:

[0033] 1-Electrode structure layer, 11-Divided annular groove, 2-Insulating layer, 3-Support body, 4-Electrically insulating layer. Detailed Implementation

[0034] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0035] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0036] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. "Several" means one or more, unless otherwise explicitly specified.

[0037] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0038] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0039] Please see Figures 1 to 4 This invention provides a pixel-generating unit, including an electrode structure layer 1, a diaphragm, a support structure, and an electrical isolation layer 4. The support structure is disposed between the electrode structure layer 1 and the diaphragm, and includes a plurality of support bodies 3 spaced apart on the electrode structure layer 1. The electrical isolation layer 4 is stacked on the electrode structure layer 1 and the support structure to electrically isolate the electrode structure layer 1 and the diaphragm. For example, the support body 3 can be made of an insulating material, and the electrode structure layer 1 can be an electrode layer made of polycrystalline silicon or an electrode layer made of the top silicon layer of an SOI (Silicon-On-Insulator) wafer. Additionally, the pixel-generating unit also includes an insulating layer 2, on which the electrode structure layer 1 is stacked.

[0040] With the above technical solution, the electrode structure layer 1 and the diaphragm are electrically isolated by the electrical isolation layer 4, which can prevent the diaphragm from contacting the electrode structure layer 1 when it moves downward, thus improving the safety of the pixel sound generation unit. The support structure is set between the electrode structure layer 1 and the diaphragm. When the diaphragm moves downward, it can be supported by the support structure and the electrical isolation layer 4 to prevent the diaphragm from being damaged due to excessive downward movement, thereby improving the reliability of the pixel sound generation unit. When the diaphragm is an ultra-thin diaphragm, it is easy for the ultra-thin diaphragm to be damaged due to excessive amplitude when it moves downward. The support structure and the electrical isolation layer 4 can provide good support for the ultra-thin diaphragm, which can prevent the ultra-thin diaphragm from being damaged when it moves downward, thus improving the service life of the ultra-thin diaphragm. At the same time, the support structure and the electrical isolation layer 4 can increase the distance between the diaphragm and the electrode structure layer 1, reduce the actual electric field strength at the support structure, thereby reducing the possibility of the support structure being broken down by the voltage between the diaphragm and the electrode structure layer 1, and thus improving the circuit safety and reliability of the pixel sound generation unit.

[0041] like Figure 2 and Figure 3As shown, the electrode structure layer 1 further includes a segmented annular groove 11, which divides the electrode structure layer 1 into an inner ring and an outer ring. The inner ring and the outer ring are electrically isolated, and the support 3 is located on the inner ring. For example, the axis of the segmented annular groove 11 is perpendicular to the front surface of the insulating layer 2, and the segmented annular groove 11 penetrates the electrode structure layer 1. The inner ring can be a cylindrical structure. For example, multiple segmented annular grooves 11 are provided, and their number is consistent with the number of support 3s. The support 3 is located at the center of the inner ring, and the multiple segmented annular grooves 11 can be arranged in an array. With this structure, the inner ring and the outer ring are electrically isolated, preventing the support 3 from being electrically connected to the outer ring, thereby further reducing the actual electric field strength at the support structure and improving the circuit safety and reliability of the pixel sound-emitting unit.

[0042] like Figure 3 As shown, the segmented annular groove 11 is further filled with an insulating structure. This structure further isolates the interior and exterior of the ring from each other, improving the circuit safety and reliability of the pixel sound-emitting unit; filling the segmented annular groove 11 with an insulating structure also enhances the overall stability of the pixel sound-emitting unit.

[0043] In some embodiments, the insulating structure and the electrical isolation layer 4 are integrally formed. For example, the insulating structure can be deposited within the segmented annular groove 11 using chemical vapor deposition, and the electrical isolation layer 4 can be formed on the electrode structure layer 1 and the support structure. This structure facilitates the forming of the insulating structure and the electrical isolation layer 4, further improving the overall stability of the pixel-based sound-generating unit.

[0044] In one alternative embodiment, the dividing groove 11 is a circular ring structure, with the difference between its inner and outer diameters ranging from 0.5 μm to 2 μm. When the difference between the inner and outer diameters of the dividing groove 11 is less than 0.5 μm, the groove width is narrow, making it easy for the inside and outside of the ring to make electrical contact, and also hindering the formation of the insulating structure of the dividing groove 11. When the difference between the inner and outer diameters of the dividing groove 11 is greater than 2 μm, the groove width is wide, reducing the overall size of the electrode structure layer 1, lowering the electrical strength of the electrode structure layer 1, and affecting the normal vibration of the diaphragm. Using this structure, when the difference between the inner and outer diameters of the dividing groove 11 is between 0.5 μm and 2 μm, the dimensions of the dividing groove 11 are optimized, ensuring electrical isolation between the inside and outside of the ring, while also facilitating the formation of the insulating structure of the dividing groove 11 and ensuring the electrical strength of the electrode structure layer 1.

[0045] like Figure 3As shown, further, the support 3 is a cylindrical structure, and the portion of the electrical isolation layer 4 stacked on the support 3 has rounded chamfers; the diameter of the cross-section of the support 3 is 1μm to 5μm, and the difference between the inner diameter of the dividing annular groove 11 and the outer diameter of the support 3 is 1μm to 3μm. For example, the support 3 is a cylindrical structure, and the portion of the electrical isolation layer 4 stacked on the cylindrical structure is a frustum structure. By forming rounded chamfers on the upper edge of the frustum structure, damage to the diaphragm after contact with the corners of the electrical isolation layer 4 can be avoided, improving the service life of the diaphragm and ensuring that the support structure and the electrical isolation layer 4 can provide good support for the diaphragm. Specifically, when the diameter of the cross-section of the support 3 is less than 1μm, the cross-sectional area of ​​the support 3 is small, resulting in poor support and a tendency to damage the diaphragm with sharp corners; when the diameter of the cross-section of the support 3 is greater than 5μm, the cross-sectional area of ​​the support 3 is large, making the support 3 difficult to process. When the difference between the inner diameter of the dividing ring groove 11 and the outer diameter of the support 3 is less than 1 μm, the support 3 is close to the dividing ring groove 11, which is not convenient for processing the dividing ring groove 11. When the difference between the inner diameter of the dividing ring groove 11 and the outer diameter of the support 3 is greater than 3 μm, the support 3 is far from the dividing ring groove 11, the size of the support 3 is small or the size of the inner ring is large, which affects the support effect of the diaphragm and the electrical strength of the electrode structure layer 1.

[0046] In some embodiments, the material of the support 3 is silicon dioxide or silicon nitride, and the height of the support 3 is 150 nm to 300 nm. With this structure, silicon dioxide or silicon nitride has insulating properties, ensuring electrical isolation between the diaphragm and the electrode structure layer 1. The height of the support 3, 150 nm to 300 nm, allows the support 3 to provide good support for the diaphragm.

[0047] In other embodiments, the material of the electrical isolation layer 4 is silicon nitride, and the thickness of the electrical isolation layer 4 is 150nm to 500nm. Using this structure, silicon nitride has insulating properties, ensuring electrical isolation between the diaphragm and the electrode structure layer 1. The thickness of the electrical isolation layer 4 (150nm to 500nm) can increase the distance between the diaphragm and the electrode structure layer 1, reducing the actual electric field strength at the support structure. This reduces the possibility of the support structure being broken down by the voltage between the diaphragm and the electrode structure layer 1, thereby improving the circuit safety and reliability of the pixel sound unit.

[0048] In other embodiments, the support 3 is made of silicon dioxide or silicon nitride, with a height of 150 nm to 300 nm, and the electrical isolation layer 4 is made of silicon nitride with a thickness of 150 nm to 500 nm. With this structure, silicon dioxide or silicon nitride provides insulation, ensuring electrical isolation between the diaphragm and the electrode structure layer 1. The height of the support 3 (150 nm to 300 nm) allows for good support of the diaphragm. Silicon nitride also provides insulation, ensuring electrical isolation between the diaphragm and the electrode structure layer 1. The thickness of the electrical isolation layer 4 (150 nm to 500 nm) increases the distance between the diaphragm and the electrode structure layer 1, reducing the actual electric field strength at the support structure. This reduces the possibility of the support structure being broken down by the voltage between the diaphragm and the electrode structure layer 1, thereby improving the circuit safety and reliability of the pixel sound unit.

[0049] like Figure 4 As shown, further, multiple supports 3 are arranged in an array. For example, the multiple supports 3 are arranged in a dot matrix of five rows and five columns. By adopting this structure, the diaphragm is supported by multiple arrayed supports 3, which can improve the reliability of the pixel sound-generating unit and ensure that the support structure can provide good support for the diaphragm.

[0050] Secondly, embodiments of the present invention also provide a digital sound-generating chip, including pixel sound-generating units as provided in the above embodiments. Exemplarily, multiple pixel sound-generating units are disposed in an array.

[0051] With the above technical solution, the electrode structure layer 1 and the diaphragm are electrically isolated by the electrical isolation layer 4, which can prevent the diaphragm from contacting the electrode structure layer 1 when it moves downward, thus improving the safety of the pixel sound generation unit. The support structure is set between the electrode structure layer 1 and the diaphragm. When the diaphragm moves downward, it can be supported by the support structure and the electrical isolation layer 4 to prevent the diaphragm from being damaged due to excessive downward movement, thereby improving the reliability of the pixel sound generation unit. When the diaphragm is an ultra-thin diaphragm, it is easy for the ultra-thin diaphragm to be damaged due to excessive amplitude when it moves downward. The support structure and the electrical isolation layer 4 can provide good support for the ultra-thin diaphragm, which can prevent the ultra-thin diaphragm from being damaged when it moves downward, thus improving the service life of the ultra-thin diaphragm. At the same time, the support structure and the electrical isolation layer 4 can increase the distance between the diaphragm and the electrode structure layer 1, reduce the actual electric field strength at the support structure, thereby reducing the possibility of the support structure being broken down by the voltage between the diaphragm and the electrode structure layer 1, and thus improving the circuit safety and reliability of the pixel sound generation unit.

[0052] Thirdly, embodiments of the present invention also provide a method for manufacturing a pixel sound-emitting unit, including the pixel sound-emitting unit as provided in the above embodiments, the manufacturing method comprising:

[0053] An electrode structure layer 1 is provided;

[0054] A first dielectric layer is deposited on electrode structure layer 1;

[0055] The first dielectric layer is etched to form a support structure, which includes a plurality of supports 3 spaced apart on the electrode structure layer 1. For example, photoresist can be spin-coated, and the photoresist patterning can be completed through exposure and development processes. The photoresist is used as a mask to etch the first dielectric layer, and the etched first dielectric layer retains only circular areas arranged in a dot matrix.

[0056] The electrode structure layer 1 is etched to form a segmented annular groove 11, which divides the electrode structure layer 1 into an electrically isolated inner ring and an outer ring, with the support 3 located on the inner ring. For example, photoresist can be further spin-coated, and the photoresist patterning can be completed through exposure and development processes to etch the electrodes in the outer annular region of the exposed area down to the underlying insulating layer 2. After etching, the electrode structure layer 1 directly below the support structure is divided into isolated cylindrical structures.

[0057] A second dielectric layer is deposited on the electrode structure layer 1 and the first dielectric layer. The second dielectric layer is partially stacked on the electrode structure layer 1 and the support structure to form an electrical isolation layer 4. The second dielectric layer is partially filled in the segmented annular groove 11 to electrically isolate the inside and outside of the ring.

[0058] For example, when depositing the first dielectric layer on the electrode structure layer 1, a low-pressure chemical vapor deposition (LPCVD) method can be used. Etching the first dielectric layer to form the support structure can be achieved by spin-coating photoresist, patterning the photoresist through exposure and development, and using the photoresist as a mask to etch the first dielectric layer. After etching, the first dielectric layer retains only circular regions arranged in a dot matrix. Etching the electrode structure layer 1 to form the segmented annular groove 11 can be further achieved by spin-coating photoresist, patterning the photoresist through exposure and development, and etching the outer annular region electrodes of the exposed area down to the underlying insulating layer 2. After etching, the electrode structure layer 1 directly below the support structure is segmented into isolated cylindrical structures. Depositing the second dielectric layer on the electrode structure layer 1 and the first dielectric layer can be performed using LCVD.

[0059] With the above technical solution, the electrode structure layer 1 and the diaphragm are electrically isolated by the electrical isolation layer 4, which can prevent the diaphragm from contacting the electrode structure layer 1 when it moves downward, thus improving the safety of the pixel sound generation unit. The support structure is set between the electrode structure layer 1 and the diaphragm. When the diaphragm moves downward, it can be supported by the support structure and the electrical isolation layer 4 to prevent the diaphragm from being damaged due to excessive downward movement, thereby improving the reliability of the pixel sound generation unit. When the diaphragm is an ultra-thin diaphragm, it is easy for the ultra-thin diaphragm to be damaged due to excessive amplitude when it moves downward. The support structure and the electrical isolation layer 4 can provide good support for the ultra-thin diaphragm, which can prevent the ultra-thin diaphragm from being damaged when it moves downward, thus improving the service life of the ultra-thin diaphragm. At the same time, the support structure and the electrical isolation layer 4 can increase the distance between the diaphragm and the electrode structure layer 1, reduce the actual electric field strength at the support structure, thereby reducing the possibility of the support structure being broken down by the voltage between the diaphragm and the electrode structure layer 1, and thus improving the circuit safety and reliability of the pixel sound generation unit.

[0060] In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0061] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A pixel-based sound-emitting unit, comprising an electrode structure layer and a diaphragm, characterized in that, Also includes: A support structure is disposed between the electrode structure layer and the diaphragm, the support structure comprising a plurality of supports spaced apart on the electrode structure layer; An electrical isolation layer is stacked on the electrode structure layer and the support structure to electrically isolate the electrode structure layer and the diaphragm. The electrode structure layer includes a segmented annular groove, which divides the electrode structure layer into an inner ring and an outer ring. The inner ring and the outer ring are electrically isolated. The support is located on the inner ring. Multiple segmented annular grooves are provided, and the number of grooves is the same as the number of supports.

2. The pixel-based sound-emitting unit according to claim 1, characterized in that, The segmented annular groove is filled with an insulating structure.

3. The pixel-based sound-emitting unit according to claim 2, characterized in that, The insulating structure and the electrical isolation layer are an integral structure.

4. The pixel-based sound-emitting unit according to claim 1, characterized in that, The dividing annular groove has a circular structure, and the difference between the inner and outer diameters of the dividing annular groove is 0.5μm to 2μm.

5. The pixel-based sound-emitting unit according to claim 4, characterized in that, The support body is a cylindrical structure, and the portion of the electrical isolation layer stacked on the support body has rounded chamfers; The diameter of the cross-section of the support is 1μm to 5μm, and the difference between the inner diameter of the dividing annular groove and the outer diameter of the support is 1μm to 3μm.

6. The pixel-based sound-emitting unit according to claim 1, characterized in that, The material of the support is silicon dioxide or silicon nitride, and the height of the support is 150nm~300nm; And / or, the material of the electrical isolation layer is silicon nitride, and the thickness of the electrical isolation layer is 150nm~500nm.

7. The pixel-based sound-emitting unit according to claim 1, characterized in that, The multiple supports are arranged in an array.

8. A digital sound-generating chip, characterized in that, Includes the pixel-emitting unit as described in any one of claims 1 to 7.

9. A method for manufacturing a pixel-based sound-emitting unit, characterized in that, The manufacturing method includes the pixel-emitting unit as described in any one of claims 1 to 7, comprising: Provide an electrode structure layer; A first dielectric layer is deposited on the electrode structure layer; The first dielectric layer is etched to form a support structure, the support structure comprising a plurality of supports spaced apart on the electrode structure layer; The electrode structure layer is etched to form a segmented annular groove, which divides the electrode structure layer into an electrically isolated inner ring and an outer ring, with the support located on the inner ring. A second dielectric layer is deposited on the electrode structure layer and the first dielectric layer. The second dielectric layer is partially stacked on the electrode structure layer and the support structure to form an electrical isolation layer. The second dielectric layer is partially filled in the segmented annular groove to electrically isolate the inside and outside of the annular groove.

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