Manipulation device for biological particles

Abstract

We provide a device for manipulating biological particles. [Solution] The manipulator for biological particles comprises a substrate, a metallic conductive layer, a working electrode, and at least one dielectric layer. The metallic conductive layer is located on the substrate. The working electrode is located on the metallic conductive layer and is electrically connected to the metallic conductive layer. At least one dielectric layer covers the metallic conductive layer and has a first recess, the first recess exposing the working electrode, the upper surface of the working electrode is higher than the bottom of the first recess, and the at least one dielectric layer is in contact with the side wall of the working electrode. The first recess of this disclosure can prevent the working electrode from coming into contact with and destroying the target biological particle.

Description

Technical Field

[0001] The present disclosure and some embodiments relate to an operating device for biological particles, and particularly to an electrode-type dielectrophoresis operating device capable of ensuring the activity of biological particles.

Background Art

[0002] With the rapid development of biotechnology in recent years, various biological particle manipulation technologies have emerged. The biological particles that can be manipulated range widely from cells, viruses, proteins to deoxyribonucleic acid (DNA). By using biological particle manipulation technology, individual biological particles can be positioned, enabling the measurement and detection of various physical, chemical, and biological properties. Furthermore, it is also possible to achieve the purpose of separating and purifying specific target biological particles by manipulating them. In the application to the quarantine field, rapid and precise manipulation of biological particles enables earlier and more accurate determination of the quantity of specific biological particles, for example, the quantity of a specific virus, contributing to the improvement of quarantine accuracy.

Summary of the Invention

Problems to be Solved by the Invention

[0003] Dielectrophoresis is one of the biological particle manipulation techniques. Dielectrophoresis is universally applicable to biological particles of various sizes and offers considerable manipulative effects. In dielectrophoretic (DEP) manipulation, for example, applying an alternating current (AC) voltage between two non-parallel electrodes creates a non-uniform electric field, generating dielectrophoretic force and rapidly moving target biological particles to predetermined electrode positions. Based on the operating mode, DEP includes electrode-based electrode dielectrophoresis (eDEP) or insulator-based insulated dielectrophoresis (iDEP). Currently, electrode dielectrophoresis (eDEP) is widely applied in microfluidic devices because it can generate high electric field gradients with low applied voltages over short intervals. However, the large gradients in electrode dielectrophoresis (eDEP) are prone to causing Joule heating, which can decompose the electrodes and generate large amounts of toxic substances. When cells approach or come into contact with electrodes for prolonged dielectrophoretic movement, damage to cells and organelles is likely to occur. [Means for solving the problem]

[0004] Some embodiments of the present disclosure provide a device for manipulating biological particles comprising a substrate, a metallic conductive layer, a working electrode, and at least one dielectric layer. The metallic conductive layer is located on the substrate. The working electrode is located on the metallic conductive layer and is electrically connected to the metallic conductive layer. At least one dielectric layer covers the metallic conductive layer and has a first recess, the first recess exposing the working electrode, the upper surface of the working electrode is higher than the bottom of the first recess, and the protective layer is in contact with the sidewall of the working electrode.

[0005] In some embodiments, at least one dielectric layer further has a second recess extending downward from the bottom of the first recess and surrounding the working electrode.

[0006] In some embodiments, the width of the top of the second recess is smaller than the width of the bottom of the first recess.

[0007] In some embodiments, the side wall of the second recess and the side wall of the first recess are separated by the bottom surface of the first recess.

[0008] In some embodiments, the upper part of the side wall of the working electrode protrudes from the protective layer.

[0009] In some embodiments, the dielectric layer includes a nitride layer and an oxide layer located on top of the nitride layer.

[0010] In some embodiments, the upper surface of the nitrided layer of at least one dielectric layer is higher than the upper surface of the working electrode.

[0011] In some embodiments, the operating device further includes via members located between the metal conductive layer and the working electrode.

[0012] In some embodiments, the width of the first recess is between 0.1 micrometers and 2 micrometers.

[0013] In some embodiments, the side wall of the first recess surrounds the working electrode. [Brief explanation of the drawing]

[0014] [Figure 1] This is a cross-sectional view showing a device for manipulating biological particles according to some embodiments of the present disclosure. [Figure 2] A cross-sectional view showing the process of forming an operating device according to some embodiments of the present disclosure. [Figure 3] A cross-sectional view showing the process of forming an operating device according to some embodiments of the present disclosure. [Figure 4] A cross-sectional view showing the process of forming an operating device according to some embodiments of the present disclosure. [Figure 5] A cross-sectional view showing the process of forming an operating device according to some embodiments of the present disclosure. [Figure 6] A cross-sectional view showing the process of forming an operating device according to some embodiments of the present disclosure. [Figure 7]A cross-sectional view showing the process of forming an operating device according to some embodiments of the present disclosure. [Figure 8] A cross-sectional view showing the process of forming an operating device according to some embodiments of the present disclosure. [Figure 9] A cross-sectional view showing the process of forming an operating device according to some embodiments of the present disclosure. [Figure 10] A cross-sectional view showing the process of forming an operating device according to some embodiments of the present disclosure. [Figure 11] A cross-sectional view showing the process of forming an operating device according to some embodiments of the present disclosure. [Figure 12] This is a top view showing an operating device of several embodiments of the present disclosure. [Figure 13] This is a top view showing an operating device of another embodiment of the present disclosure. [Modes for carrying out the invention]

[0015] Some embodiments of this disclosure relate to apparatus for handling biological particles. The apparatus for handling biological particles is applicable to biological particle handling techniques and is applicable to the field of electrophoresis (eDEP). Biological particles may include cells, bacteria, viruses, proteins, deoxyribonucleic acid (DNA), and the like. When handling biological particles, the apparatus for handling biological particles of this disclosure can avoid direct contact between the biological particles and electrodes when performing electrophoresis, significantly reduce the harm that Joule heat or electrochemical decomposition substances inflict on biological particles such as cells, and improve the activity of the biological particles.

[0016] FIG. 1 is a cross-sectional view showing an operating device according to some embodiments of the present disclosure. Referring to FIG. 1, the operating device includes a substrate 110, a metal conductive layer 120, an insulating layer 130, a via member 140, an active electrode 150, and a dielectric layer 160. The operating device can be used to adsorb target biological particles B. In some embodiments, the target biological particles B may be biological particles and may include cells, bacteria, viruses, etc.

[0017] In some embodiments, the substrate 110 includes a base material 112 and an insulating layer 114. The substrate 110 may include, for example, but is not limited to, other semiconductor materials such as gallium nitride (GaN), silicon carbide (SiC), silicon germanium (SiGe), germanium, or combinations thereof. The base material 112 may be, for example, a silicon substrate. Depending on the design requirements in the technical field, the base material 112 may include various different doping configurations. In some embodiments, the base material 112 may be a highly doped low-resistivity semiconductor substrate. In other embodiments, the substrate 110 is a glass substrate and does not have the insulating layer 114.

[0018] The insulating layer 114 is located on the base material 112. In some embodiments, the insulating layer 114 may include, for example, but is not limited to, oxides, nitrides, oxynitrides, or combinations thereof such as silicon oxide, silicon nitride, silicon oxynitride, etc. By adopting a low dielectric constant (low-K) material for the insulating layer 114, the operating device has good insulating properties. In a certain embodiment, the thickness of the insulating layer 114 is from about 0.02 micrometers (μm) to about 0.6 micrometers, for example, about 0.10 micrometers, about 0.15 micrometers, or about 0.20 micrometers.

[0019] The metal conductive layer 120 is located on the substrate 110. In some embodiments, the metal conductive layer 120 may include, but is not limited to, titanium (Ti), nickel (Ni), silver (Ag), aluminum (Al), aluminum copper alloy (AlCu), aluminum silicon copper alloy (AlSiCu), or a combination thereof. In some embodiments, the thickness of the metal conductive layer 120 is from about 0.02 micrometers to about 0.7 micrometers, for example, about 0.1 micrometer, 0.2 micrometer, 0.3 micrometer, 0.4 micrometer, about 0.5 micrometer or about 0.6 micrometer.

[0020] The insulating layer 130 covers the metal conductive layer 120 and contacts the upper surface and sidewalls of the metal conductive layer 120. In some embodiments, the insulating layer 130 may include, but is not limited to, oxides such as silicon oxide, silicon nitride, silicon oxynitride, nitrides, oxynitrides, or a combination or compound thereof. In some embodiments, the material of the insulating layer 114 is the same as the material of the insulating layer 130. In some embodiments, the material of the insulating layer 114 is different from the material of the insulating layer 130.

[0021] The via member 140 is located within the insulating layer 130 and is located above the metal conductive layer 120. The width of the via member 140 may be smaller than the width of the metal conductive layer 120, and the insulating layer 130 surrounds the via member 140. In some embodiments, the via member 140 may include, but is not limited to, tungsten (W), copper (Cu), or a combination thereof. In some embodiments, the thickness of the via member 140 is from about 0.2 micrometers to about 0.6 micrometers.

[0022] The working electrode 150 is located on the metal conductive layer 120 and electrically connects the via member 140 to the metal conductive layer 120. That is, the via member 140 is located between the metal conductive layer 120 and the working electrode 150. The width of the working electrode 150 may be smaller than the width of the via member 140. Each working electrode 150 protrudes above the via member 140 at a height H1. In some embodiments, the height H1 of the working electrode 150 is about 0.05 micrometers to about 0.5 micrometers, for example, about 0.05 micrometers, 0.1 micrometers, 0.2 micrometers, about 0.3 micrometers, or about 0.4 micrometers. In some embodiments, the width of the working electrode 150 is about 0.08 micrometers to about 0.4 micrometers, for example, about 0.08 micrometers, 0.1 micrometers, 0.2 micrometers, or about 0.3 micrometers. In one embodiment, the working electrode 150 has an aspect ratio between approximately 0.125 and approximately 7.5, for example, approximately 0.2 or approximately 0.3.

[0023] In some embodiments of this disclosure, the shape of the working electrode 150 may be a cylinder or a regular polygonal prism, such as a triangular prism, a square prism, a pentagonal prism, a hexagonal prism, or an octagonal prism. In some embodiments, the working electrode 150 may include, but is not limited to, tantalum (Ta), tantalum nitride (TaN), copper (Cu), titanium (Ti), titanium nitride (TiN), tungsten (W), titanium (Ti), nickel (Ni), silver (Ag), aluminum (Al), copper-aluminum alloy (AlCu), copper-aluminum-silicon alloy (AlSiCu), or a combination thereof. In some embodiments, the material of the working electrode 150 is preferably titanium nitride (TiN).

[0024] The dielectric layer 160 covers the insulating layer 130, the via member 140, and the working electrode 150. The dielectric layer 160 has a recess R1, the recess R1 exposing the working electrode 150, and the upper surface of the working electrode 150 is higher than the bottom of the recess R1, with a thickness T1 greater than zero between the bottom of the recess R1 and the bottom of the dielectric layer 160. In other words, the dielectric layer 160 is not directly above the working electrode 150. In some embodiments, the thickness T1 between the bottom of the recess R1 and the bottom of the dielectric layer 160 is about 0.03 micrometers to about 0.15 micrometers. In some embodiments, the recess R1 may have a substantially circular planar contour. In some embodiments, the top of the recess R1 has a width W1 (or diameter), and the bottom of the recess R1 has a width W2, where width W1 is greater than width W2. In other words, in the cross-sectional view of Figure 1, the recess R1 has a contour that narrows downwards. In some embodiments, the width W1 is the maximum width of the recess R1.

[0025] In some embodiments, the maximum width of the recess R1 (e.g., width W1) is smaller than the size of the target biological particle B. In some embodiments, the width W1 of the recess R1 is between approximately 0.1 micrometers and 2 micrometers. In some embodiments, the upper surface of the working electrode 150 is higher than the bottom of the recess R1 by a height H2, with a height H2 of approximately 0.05 micrometers and 0.2 micrometers. That is, the dielectric layer 160 is in contact with the side wall of the working electrode 150, and the upper part of the side wall of the working electrode 150 protrudes from the dielectric layer 160.

[0026] The dielectric layer 160 further has a recess R2, which is located at the bottom of the recess R1, surrounding the working electrode 150, and the bottom of the recess R2 is lower than the bottom of the recess R1. More specifically, the recess R2 extends downward from the bottom surface of the recess R1, thereby separating the side wall of the recess R2 from the side wall of the recess R1 via the bottom surface of the recess R1. In some embodiments, the top of the recess R2 has a width W3 that is smaller than the bottom width W2 of the recess R1. There is a further thickness T2 greater than zero between the bottom of the recess R2 and the bottom of the dielectric layer 160. In some embodiments, the thickness T2 between the bottom of the recess R2 and the bottom of the dielectric layer 160 is about 0.02 micrometers to about 0.05 micrometers.

[0027] The dielectric layer 160 can be made of a dielectric material. In some embodiments, the dielectric layer 160 may, but is not limited to, oxides such as silicon oxide, silicon nitride, silicon oxide nitride, nitride oxide, or combinations thereof or compounds thereof. For example, the dielectric layer 160 may include a nitride layer 162 and an oxide layer 164, with the oxide layer 164 located on top of the nitride layer 162.

[0028] When performing dielectrophoretic manipulation techniques on biological particles, the target biological particles B can be attracted to the working electrode 150 by placing a solution containing the target biological particles B on a manipulating device having an arrangement that forms a non-parallel electric field and applying an AC voltage of a specific frequency range to the working electrode 150. Subsequently, processes such as detection, separation, and electroporation can be performed on the target biological particles B. The recess R1 in some embodiments of this disclosure can be used to significantly improve the viability of the target biological particles B when using electrode-type dielectrophoresis. Specifically, since the recess R1 in the dielectric layer 160 exposes the working electrode 150, an electrode-type dielectrophoresis mode can be used, and when maintaining the execution of biological particle manipulation techniques at low voltage, the target biological particles B are attracted by dielectrophoretic force and move towards the working electrode 150 where the electric field is concentrated or diverged, but ultimately there is no substantial contact between the target biological particles B and the working electrode 150, significantly reducing damage to the target biological particles B from Joule heat and potential chemical decomposition materials generated by the operating electrical signal on the working electrode 150. Furthermore, since the width W1 of the recess R1 in the dielectric layer 160 is smaller than the size of the target biological particle B, it is guaranteed that the target biological particle B will not fall into the recess R1 and will not come into contact with the working electrode 150.

[0029] Figures 2 to 11 are cross-sectional views showing the formation process of an operating device in some embodiments of the present disclosure. Referring to Figures 2 and 3, a substrate 110 is provided. In some embodiments, the substrate 110 comprises a base material 112 and an insulating layer 114, the insulating layer 114 being formed on the base material 112. The insulating layer 114 can be formed by atomic layer deposition (ALD), physical vapor deposition (PVD), chemical vapor deposition (CVD), chemical oxidation, heat oxidation and / or other suitable methods. In some embodiments, the insulating layer 114 may, but is not limited to, oxides, nitrides, oxide nitrides, such as silicon oxide, silicon nitride, silicon oxide nitride, etc.

[0030] Referring to Figure 4, a metallic conductive layer 120 is formed on the insulating layer 114 of the substrate 110. In some embodiments, the metallic conductive layer 120 can be formed by PVD, CVD, electron beam evaporation, sputtering, electroplating and / or other suitable processes. In some embodiments, the metallic conductive layer 120 may include, but is not limited to, titanium (Ti), nickel (Ni), silver (Ag), aluminum (Al), copper-aluminum alloy (AlCu), copper-aluminum-silicon alloy (AlSiCu), or a combination thereof.

[0031] Referring to Figure 5, a patterning process is performed on the metal conductive layer 120. Specifically, a patterned photoresist layer (not shown) can be formed on the metal conductive layer 120 using a mask and a lithography process. This photoresist layer may be, for example, a positive-type or negative-type photoresist. Next, an etching process is performed on the metal conductive layer 120 using the patterned photoresist layer to expose the upper surface of a portion of the underlying insulating layer 114.

[0032] Referring to Figure 6, an insulating layer 130 is deposited on the insulating layer 114 and the metallic conductive layer 120. In some embodiments, the insulating layer 130 may be multilayered, with each layer being made of a different material. In some embodiments, the insulating layer 130 may be multilayered, with each layer being made of the same material. In some embodiments, the insulating layer 130 may, but is not limited to, oxides, nitrides, oxide nitrides, such as silicon oxide, silicon nitride, silicon oxide nitride, etc. In one embodiment, the insulating layer 130 is tetraethoxysilane. In some embodiments, the insulating material layer can be formed by PVD, CVD, plasma-enhanced chemical vapor deposition (PECVD) and / or other suitable processes.

[0033] Referring to Figure 7, via members 140 are formed within the insulating layer 130. Specifically, holes are formed in the insulating layer 130, conductive material is filled into the holes, and finally a planarization process is performed to remove any excess material that has overflowed from the holes, thereby forming the via members 140 within the insulating layer 130. In some embodiments, the via members 140 may include, but are not limited to, tungsten (W), copper (Cu), or a combination thereof.

[0034] Referring to Figure 8, a conductive layer 150' is deposited on the insulating layer 130 and the via member 140. In some embodiments, the conductive layer 150' can be formed by PVD, CVD, electron beam evaporation, sputtering, plating and / or other suitable processes. In some embodiments, the conductive layer 150' may, but is not limited to, tantalum (Ta), tantalum nitride (TaN), copper (Cu), titanium (Ti), titanium nitride (TiN), tungsten (W), or a combination thereof.

[0035] Next, referring to Figure 9, a patterning process is performed on the conductive layer 150' to form multiple working electrodes 150. Specifically, a patterned photoresist layer can be formed on the conductive layer 150' using a mask and lithography process, and this photoresist layer may be, for example, a positive-type photoresist or a negative-type photoresist. Next, an etching process is performed on the conductive layer 150' using the patterned photoresist layer to form multiple working electrodes 150, and to expose the upper surface of the insulating layer 130 and a portion of the upper surface of the via member 140. The working electrodes 150 have a height H1.

[0036] Referring to Figure 10, a dielectric layer 160 is formed on the insulating layer 130 and the working electrode 150. In some embodiments, the insulating layer 130 may be multilayered, with each layer being made of a different material. In some embodiments, the dielectric layer 160 may be multilayered, with each layer being made of the same material. In some embodiments, the insulating layer 130 may, but is not limited to, oxides, nitrides, oxide nitrides, or combinations thereof, such as silicon oxide, silicon nitride, silicon oxide nitride, etc. In one embodiment, the insulating layer 130 is tetraethoxysilane. For example, the dielectric layer 160 may include a nitride layer 162 and an oxide layer 164, with the oxide layer 164 located on top of the nitride layer 162. The nitride layer 162 completely covers the working electrode 150 and is used to prevent the working electrode 150 from being oxidized simultaneously when the oxide layer 164 is formed, thereby not affecting the resistance value of the working electrode 150. In some embodiments, the dielectric layer 160 can be formed by PVD, CVD, plasma-enhanced chemical vapor deposition (PECVD), and / or other suitable processes. In some embodiments, the entire upper surface of the nitride layer 162 is higher than the upper surface of the working electrode 150, as shown in Figure 10. In other embodiments, only a portion of the upper surface of the nitride layer 162 is higher than the upper surface of the working electrode 150. For example, since the nitride layer 162 is a thin film layer formed together with the insulating layer 130 and the working electrode 150, only the upper surface of the nitride layer 162 near the top of the working electrode 150 is higher than the upper surface of the working electrode 150.

[0037] Referring to Figure 11, a recess R1 is formed within the dielectric layer 160. Specifically, a patterned photoresist layer (not shown) can be formed on the dielectric layer 160 using a mask and a lithography process, and this photoresist layer is, for example, a positive-type or negative-type photoresist. Next, an etching process is performed on the dielectric layer 160 using the patterned photoresist layer to expose the working electrode 150. Since the etching process is etching selective for both the dielectric layer 160 and the working electrode 150, the working electrode 150 is slightly etched when the recess R1 is formed (i.e., the etching rate of the dielectric layer 160 by the etching process is much greater than the etching rate of the working electrode 150). In some embodiments, after the recess R1 is formed, the upper surface of the nitride layer 162 of the dielectric layer 160 may be higher than the upper surface of the working electrode 150. In other embodiments, after the recess R1 is formed, the upper surface of the nitride layer 162 of the dielectric layer 160 may be lower than the upper surface of the working electrode 150. The top of the recess R1 has a width W1 (or diameter), and the bottom of the recess R1 has a width W2 that is greater than the width W2, and the width W1 is greater than the width W2. Since the width W1 of the recess R1 is smaller than the size of the target biological particle, the target biological particle will not come into direct contact with the working electrode 150. When the etching process is performed, the dielectric layer 160 is not completely etched, so there is a thickness T1 between the bottom of the recess R1 and the bottom of the dielectric layer 160. That is, the top of the working electrode 150 is exposed to the environment, the bottom of the working electrode 150 is covered by the dielectric layer 160, and the top surface of the working electrode 150 is higher than the bottom of the recess R1 by a height H2. In some embodiments, when the dielectric layer 160 is etched to form the recess R1, the recess R1 may not be perfectly flat due to the presence of the working electrode 150. For example, because the etching process etches the material around the working electrode 150 at a fast rate, a recess R2 surrounding the working electrode 150 is formed at the bottom of the recess R1. There is a thickness T2 greater than zero between the bottom of the recess R2 and the bottom of the dielectric layer 160, and the top of the recess R2 has a width W3 that is smaller than the bottom width W2 of the recess R1.

[0038] Figure 12 is a top view showing an operating device of several embodiments of the present disclosure. Figures 1 to 11 can be cross-sectional views shown along the line A-A' in Figure 12. In some embodiments, one recess R1 corresponds to a plurality of working electrodes 150, the longitudinal direction of the recess R1 is along a first direction D1, and the working electrodes 150 within the recess R1 are also arranged along the first direction D1. That is, the side walls of the recess R1 are located on both sides of the working electrodes 150.

[0039] Figure 13 is a top view showing an operating device of another embodiment of the present disclosure. Figures 1 to 11 can be cross-sectional views shown along line A-A' in Figure 13. In some embodiments, one recess R1 may correspond to one working electrode 150. That is, the side wall of the recess R1 surrounds the working electrode 150.

[0040] It should be noted that this disclosure does not limit the correspondence and arrangement of the recess R1 and the working electrode 150. If the width W1 of the recess R1 is smaller than the size of the target biological particles, and the target biological particles do not fall into the recess R1 and come into direct contact with the working electrode 150, the recess R1 can be used to improve the dielectric force between the target biological particles and the working electrode 150 without destroying the target biological particles. This disclosure does not limit the shape of the recess R1, and in some embodiments, the shape of the recess R1 can be square, circular, triangular, etc.

[0041] In summary, the operating apparatus in some embodiments of the present disclosure includes a protective layer having a recess. Because the recess exposes the working electrode, when performing biological particle manipulation techniques using an electrode-type dielectrophoresis mode, as the target biological particle is attracted by dielectrophoretic force and moves toward the working electrode where the electric field is concentrated or diverged, there is ultimately no substantial contact between the target biological particle and the working electrode, and damage to the target biological particle B from the operating electrical signal and Joule heat on the working electrode can be greatly reduced. Furthermore, because the size of the recess is smaller than the size of the target biological particle, the recess can prevent the working electrode from coming into contact with and destroying the target biological particle.

[0042] The foregoing describes only some of the embodiments of the Disclosure, not all embodiments, and any equivalent modifications made by a person skilled in the art by reading the specification of the Disclosure are also included in the claims of the Disclosure. [Explanation of Symbols]

[0043] 110: Circuit board 112: Base material 114, 130: Insulating layer 120: Metal conductive layer 140: Via component 150: Working electrode 150': Conductive layer 160: Dielectric layer 162: Nitrided layer 164: Oxide layer B: Target biological particle D1: Direction H1, H2: Height R1, R2: Recessed T1, T2: thickness W1, W2, W3: Width

Claims

1. A device for manipulating biological particles, circuit board and A metal conductive layer located on the aforementioned substrate, A working electrode is located on the aforementioned metal conductive layer and is electrically connected to the aforementioned metal conductive layer. A protective layer covering the metal conductive layer, having a first recess, the first recess exposing the working electrode, and the upper surface of the working electrode being higher than the bottom of the first recess, The protective layer contacts the side wall of the working electrode. Operating device.

2. The operating device according to claim 1, wherein the protective layer further has a second recess that extends downward from the bottom of the first recess and surrounds the working electrode.

3. The operating device according to claim 2, wherein the width of the top of the second recess is smaller than the width of the bottom of the first recess.

4. The operating device according to claim 2, wherein the side wall of the second recess and the side wall of the first recess are separated by the bottom surface of the first recess.

5. The operating device according to claim 1, wherein the upper part of the side wall of the working electrode protrudes from the protective layer.

6. The aforementioned protective layer is Nitrided layer, The oxide layer located on the nitride layer, The operating device according to claim 1.

7. The operating device according to claim 6, wherein the upper surface of the nitrided layer of the protective layer is higher than the upper surface of the working electrode.

8. The operating device according to claim 1, further comprising a via member located between the metal conductive layer and the working electrode.

9. The operating device according to claim 1, wherein the width of the first recess is between 0.1 micrometers and 2 micrometers.

10. The operating device according to claim 1, wherein the side wall of the first recess surrounds the working electrode.

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