Ceramic electrode, thin film sensor having the same, and manufacturing method of the ceramic electrode

Abstract

The ceramic electrode provided by the present invention, a thin film sensor having the same, and a manufacturing method of the ceramic electrode belong to the technical field of thin film sensors. The ceramic electrode includes: a ceramic substrate, a fixed electrode layer, and a support structure. The support structure is deposited on the same surface of the ceramic substrate where the fixed electrode layer is located by electroplating. There is a plating layer between the support structure and the ceramic substrate, and the thickness of the plating layer is equal to that of the fixed electrode layer. For the ceramic electrode of the present invention, on the surface of the ceramic substrate where the electrode layer is provided, a plating layer before electroforming is also provided by screen printing or physical vapor deposition, and then a support structure is provided on the plating layer. Moreover, the thickness of the support structure is precisely controlled by electroforming, which can not only avoid the influence of the thickness of the electrode layer formed by screen printing or physical vapor deposition on the electrode spacing, but also precisely control the thickness of the support structure, thereby ensuring the accuracy of the sensor.

Description

Technical Field

[0001] The present invention relates to the technical field of thin film sensors, and particularly relates to a ceramic electrode, a thin film sensor having the same, and a manufacturing method of the ceramic electrode. Background Art

[0002] A thin film sensor usually consists of a movable electrode made of a metal diaphragm and a fixed electrode with a ceramic or other insulating material as the substrate. The metal movable electrode and the ceramic fixed electrode are spaced at a fixed distance to establish a capacitance. From the capacitance formula C = Ae r e o / d (where A is the corresponding area of the two electrodes, e r is the relative permittivity of the material, e o is the vacuum permittivity, and d is the distance between the two plates), it can be seen that when the electrode area and the permittivity are fixed, the capacitance value is mainly determined by the d value. In high vacuum measurement, if you want to accurately measure the vacuum degree of the chamber to be measured, the smaller d is, the better.

[0003] Generally, we set the d value between 100um and 200um. Usually, for the processing of different ranges of sensors and different batches of plates of the same range, a spacer with adjustable thickness is required to select the appropriate spacing d. The currently common method is to process strips with different thickness gradients for selection. And, since the chamber between the ceramic electrode and the diaphragm electrode in the sensor needs to be evacuated, air guiding grooves need to be etched on the strip to be used as an air guiding spacer.

[0004] Since the strip is too thin and there are many required gradient thicknesses, the processing cost is extremely high, and it is also difficult to etch air guiding grooves on such a thin strip. On the other hand, the ceramic fixed electrode forms an electrode layer on the ceramic by screen printing or physical vapor deposition, and the thickness of the electrode layer is usually between 8um and 16um. The superposition of the processing errors of the screen printed electrode layer and the air guiding spacer will greatly affect the distance between the electrodes. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the defect that the ceramic electrode in the prior art has a certain thickness due to the electrode layer formed by screen printing or physical vapor deposition, and after being superimposed with the air guiding spacer arranged by the strip, it will greatly affect the distance between the electrodes, so as to provide a ceramic electrode that can avoid the above errors.

[0006] The present invention also provides a thin film sensor having the above ceramic electrode.

[0007] The present invention also provides a manufacturing method of the above ceramic electrode.

[0008] To solve the above technical problems, the present invention provides a ceramic electrode, which is used to be arranged in the reference pressure chamber of a thin film sensor and opposite to the diaphragm electrode, and includes:

[0009] A ceramic substrate;

[0010] A fixed electrode layer, which is arranged on one side of the ceramic substrate for facing the diaphragm electrode by means of screen printing or physical vapor deposition;

[0011] A support structure, which is deposited on the same surface of the ceramic substrate where the fixed electrode layer is located by electroplating. There is a plating layer between the support structure and the ceramic substrate, and the thickness of the plating layer is equal to that of the fixed electrode layer.

[0012] As a preferred solution, the support structure is located on the outer circle of the fixed electrode layer.

[0013] As a preferred solution, there are multiple support structures, and the multiple support structures are evenly arranged along the circumferential direction.

[0014] As a preferred solution, the multiple support structures form an unclosed ring.

[0015] As a preferred solution, the support structure is an arc structure.

[0016] The present invention also provides a thin film sensor, including:

[0017] A housing, which has an inner cavity;

[0018] A diaphragm electrode, which is arranged in the housing and divides the inner cavity of the housing into a reference pressure chamber and an external pressure test chamber. The external pressure test chamber is communicated with the outside through an inlet pipe;

[0019] A ceramic electrode, which is located in the reference pressure chamber and opposite to the diaphragm electrode; on the side of the ceramic electrode facing the diaphragm electrode, there is a fixed electrode layer arranged by means of screen printing or physical vapor deposition;

[0020] On the side of the ceramic electrode facing the diaphragm electrode, there is a support structure deposited by electroplating. There is a plating layer between the support structure and the ceramic substrate of the ceramic electrode, and the thickness of the plating layer is equal to that of the fixed electrode layer.

[0021] As a preferred solution, the support structure is an unclosed ring arranged on the outer circle of the fixed electrode layer.

[0022] The present invention also provides a manufacturing method of a ceramic electrode, including the following steps:

[0023] Set a fixed electrode layer and a plating layer, and form the fixed electrode layer and the plating layer on the ceramic substrate by screen printing or physical vapor deposition, and make the thickness of the plating layer equal to that of the fixed electrode layer;

[0024] Set a gas guiding layer, and deposit a support structure on the plating layer by electroforming, so that a plurality of the support structures are arranged at intervals on the ceramic substrate, and the top surface of the support structure is adapted to be in direct contact with the diaphragm electrode.

[0025] As a preferred solution, the plating layer is arranged on the outer circle of the fixed electrode layer.

[0026] As a preferred solution, the thickness of the support structure is a multiple of 25 microns.

[0027] The technical solution of the present invention has the following advantages:

[0028] 1. For the ceramic electrode provided by the present invention, on the side of the ceramic substrate where the electrode layer is arranged, a plating layer before electroforming is also arranged by screen printing or physical vapor deposition, and then a support structure is arranged on the plating layer, and the support structure is precisely controlled in thickness by electroforming. This not only can avoid the influence of the thickness of the electrode layer formed by screen printing or physical vapor deposition on the electrode spacing, but also can precisely control the thickness of the support structure, thereby ensuring the accuracy of the sensor.

[0029] 2. For the thin film sensor provided by the present invention, by using the above ceramic electrode, the electroformed support structure can precisely deposit gas guiding layers with different thicknesses on the ceramic substrate, so there is no need to additionally process a gas guiding gasket to adjust the thickness.

[0030] 3. For the manufacturing method of the ceramic electrode provided by the present invention, when making an electrode for the ceramic, a plating layer with the same thickness as the electrode layer is formed on the ceramic substrate by screen printing or physical vapor deposition, and then support structures with different thicknesses are electroformed on the plating layer to form a gas guiding layer. This can avoid the influence of the thickness of the electrode layer formed by screen printing or physical vapor deposition on the electrode spacing, and by using electroforming to deposit the support structure, the distance between the electrodes can be precisely controlled, thereby ensuring the accuracy of the sensor.

[0031] 4. For the manufacturing method of the ceramic electrode provided by the present invention, the gas guiding layer formed by the support structures with different thicknesses electroformed on the plating layer of the ceramic substrate can be in a gradient of every 25um according to requirements, so as to precisely control the spacing of the adjustable electrodes. Description of the Drawings

[0032] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are 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.

[0033] Figure 1 It is a front view cross-sectional view of an embodiment of the thin film sensor of the present invention.

[0034] Figure 2 It is a three-dimensional structural schematic diagram of an embodiment of the ceramic electrode.

[0035] Description of the reference numerals:

[0036] 1. Housing; 2. Inlet pipe; 3. Ceramic electrode; 4. Diaphragm electrode; 5. Reference pressure chamber; 6. External pressure test chamber; 7. Fixed electrode layer; 8. Support structure; 9. Coating; 10. Ceramic substrate. Specific embodiments

[0037] The following will clearly and completely describe the technical solutions of the present invention with reference to the drawings. Obviously, the described embodiments are some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

[0038] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It 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 of the present invention.

[0039] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", and "connection" should 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 directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. 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 situations.

[0040] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0041] As Figure 1 shown, this embodiment provides a specific implementation of a thin-film sensor, including: a housing 1 and an inlet pipe 2 connected to the housing 1 and communicating with the inner cavity of the housing 1. A diaphragm electrode 4 is provided in the housing 1. The diaphragm electrode 4 divides the pressure chamber in the housing 1 into a reference pressure chamber 5 and an external pressure test chamber 6. The external pressure test chamber 6 can communicate with the chamber to be measured through the inlet pipe 2. A ceramic electrode 3 is provided in the reference pressure chamber 5. The ceramic electrode 3 faces the diaphragm electrode 4. A fixed electrode layer 7 and a support structure 8 are provided on the surface of the ceramic electrode 3 facing the diaphragm electrode 4.

[0042] As Figure 2 shown, the fixed electrode layer 7 of the ceramic electrode is arranged on a ceramic substrate 10 by means of screen printing or physical vapor deposition, and the support structure 8 is deposited by electroplating. A plating layer 9 is provided between the support structure 8 and the ceramic substrate 10. The plating layer 9 is arranged simultaneously with the fixed electrode layer 7 and is also arranged on the ceramic substrate 10 by means of screen printing or physical vapor deposition. The thickness of the plating layer 9 is equal to that of the fixed electrode layer 7. The physical vapor deposition method includes: evaporation plating, magnetron sputtering coating, etc.

[0043] The support structure 8 is an arc-shaped structure. The support structure 8 is located outside the fixed electrode layer 7 and there are multiple of them. The multiple support structures 8 are evenly arranged along the circumferential direction outside the fixed electrode layer 7 to form an unclosed ring. In addition, as an alternative implementation, a single support structure 8 can be in a shape other than an arc, such as a cylinder, and a non-closed ring is formed by multiple support structures 8.

[0044] The manufacturing method of the ceramic electrode includes the following steps:

[0045] In the first step, the fixed electrode layer 7 and the plating layer 9 are arranged. The fixed electrode layer 7 and the plating layer 9 are formed on the ceramic substrate 10 by means of screen printing or physical vapor deposition, and the thickness of the plating layer 9 is equal to that of the fixed electrode layer 7; wherein, the plating layer 9 is arranged outside the fixed electrode layer 7.

[0046] In the second step, a gas guiding layer is arranged. The support structure 8 is deposited on the plating layer 9 by electroforming, so that there are multiple support structures 8 arranged at intervals on the ceramic substrate 10. The top surface of the support structure 8 is suitable for direct contact with the diaphragm electrode 4. According to actual needs, the thickness of the support structure 8 is adjustable. The thickness of the support structure 8 is taken as a gradient of 25 microns, that is, the thickness of the support structure 8 is set as a multiple of 25 microns to precisely control the electrode spacing of the sensor.

[0047] Obviously, the above embodiments are merely examples given for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation manners here. And the obvious changes or modifications derived therefrom still fall within the protection scope of the present invention.

Claims

1. A ceramic electrode, which is used to be arranged in a reference pressure chamber (5) of a thin film sensor and opposite to a diaphragm electrode (4), is characterized in that, Comprising: A ceramic substrate (10); A fixed electrode layer (7) disposed on one side of the ceramic substrate (10) opposite to the diaphragm electrode (4) by means of screen printing or physical vapor deposition; A support structure (8) deposited on the same surface of the ceramic substrate (10) where the fixed electrode layer (7) is located by electroplating, and the top surface of the support structure (8) is adapted to directly contact the diaphragm electrode (4); There is a plating layer (9) between the support structure (8) and the ceramic substrate (10), the plating layer (9) has the same thickness as the fixed electrode layer (7), the plating layer (9) is set simultaneously with the fixed electrode layer (7), and is also disposed on the ceramic substrate (10) by means of screen printing or physical vapor deposition.

2. The ceramic electrode according to claim 1, wherein The support structure (8) is located on the outer circle of the fixed electrode layer (7).

3. The ceramic electrode according to claim 1, wherein There are a plurality of the support structures (8), and the plurality of support structures (8) are evenly arranged in the circumferential direction.

4. The ceramic electrode according to claim 3, characterized in that, The plurality of support structures (8) form an unclosed ring.

5. The ceramic electrode according to claim 4, characterized in that, The support structure (8) is an arc structure.

6. A thin film sensor, characterized in that, Comprising: A housing (1) having an inner cavity; A diaphragm electrode (4) disposed in the housing (1) and dividing the inner cavity of the housing (1) into a reference pressure chamber (5) and an external pressure test chamber (6), and the external pressure test chamber (6) communicates with the outside through an inlet pipe (2); The ceramic electrode (3) according to any one of claims 1-5, located in the reference pressure chamber (5) and opposite to the diaphragm electrode (4).

7. The thin film sensor according to claim 6, characterized in that, The support structure (8) is an unclosed ring disposed on the outer circle of the fixed electrode layer (7).

8. A method for manufacturing a ceramic electrode, characterized in that, Comprising the following steps: Setting the fixed electrode layer (7) and the plating layer (9), forming the fixed electrode layer (7) and the plating layer (9) on the ceramic substrate (10) by means of screen printing or physical vapor deposition, and making the plating layer (9) have the same thickness as the fixed electrode layer (7); Setting the gas guiding layer, depositing the support structure (8) on the plating layer (9) by electroforming, so that there are a plurality of the support structures (8) spaced apart on the ceramic substrate (10), and the top surface of the support structure (8) is adapted to directly contact the diaphragm electrode (4).

9. The manufacturing method of the ceramic electrode according to claim 8, characterized in that, The plating layer (9) is disposed on the outer circle of the fixed electrode layer (7).

10. The manufacturing method of the ceramic electrode according to claim 8, characterized in that, The thickness of the support structure (8) is a multiple of 25 microns.

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