Pressure sensor and manufacturing method thereof

Abstract

The pressure sensor includes a top cover component, an upper base (120), and a movable membrane (200), the top and bottom of which are formed with openings, the top cover component sealing the top opening of the upper base (120), and the movable membrane (200) sealing the bottom opening of the upper base (120). The top cover component, the upper base (120), and the movable membrane (200) together form a pressure reference chamber (100), and the pressure sensor is adapted to detect the pressure of the top cover component of the movable membrane (200) based on the state of the movable membrane (200). The pressure sensor detects the gas pressure on the side remote from the pressure reference chamber (100), the top cover component is formed with at least one air passage (510) and is used to communicate the pressure reference chamber (100) with the outside, the top cover component includes at least one closure member (521) and is used to seal the air passage (510), the closure member (521) melts at least partially when heated to a temperature higher than a predetermined melting temperature and solidifies after cooling to seal the air passage (510). A method for manufacturing the pressure sensor is further provided. The pressure sensor has high manufacturing efficiency, a robust structure, and high pressure detection accuracy.

Description

[Technical field]

[0001] The present invention relates to the field of semiconductor processing equipment, and more particularly to a pressure sensor and a method for manufacturing the pressure sensor. [Background technology]

[0002] In the semiconductor industry, when producing chips using methods such as etching, it is usually necessary to precisely control the gas pressure, flow rate, etc., and also to precisely monitor the pressure of the process gas in order to produce high-quality products.

[0003] However, the manufacturing process of conventional pressure sensors is complicated, the manufacturing efficiency is low, and there is often a problem of accuracy decreasing during use. Therefore, how to provide a pressure sensor structure that is highly stable and easy to manufacture has become a technical problem that needs to be solved urgently in this field. Summary of the Invention [Means for solving the problem]

[0004] An object of the present invention is to provide a pressure sensor and a method for manufacturing the pressure sensor, which, when used, has high manufacturing efficiency, a robust structure, and high pressure detection accuracy.

[0005] In order to achieve the above object, one aspect of the present invention provides a pressure sensor including a top cover component, an upper base, and a movable membrane, wherein openings are formed on both the top and bottom of the top base, the top cover component seals the top opening of the top base, and the movable membrane seals the bottom opening of the top base, the top cover component, the upper base, and the movable membrane together form a pressure reference chamber, and the pressure sensor is used to detect a gas pressure on a side of the movable membrane away from the top cover component based on a state of the movable membrane, wherein at least one air conduction passage is formed in the top cover component, the air conduction passage is used to communicate the pressure reference chamber with the outside, the top cover component includes at least one blocking member, the blocking member is used to block the air conduction passage, and the blocking member at least partially melts when heated to a temperature higher than a predetermined melting temperature and solidifies after cooling, thereby sealing the air conduction passage.

[0006] Optionally, the top cover component includes a top cover body that seals the upper opening of the upper base, the top cover body has an air passage penetrating therethrough in its thickness direction, and the blocking member before melting is provided on the top cover body in correspondence with the air passage.

[0007] Optionally, the cross-sectional dimension of the air passage at any position is equal to or smaller than the cross-sectional dimension of the air passage remote from the movable membrane.

[0008] Optionally, the air passage includes an accommodating hole formed on the upper surface of the top cover body and a through hole penetrating from the bottom end of the accommodating hole to the bottom surface of the top cover body, the hole diameter of the accommodating hole being larger than the hole diameter of the through hole, and the blocking member before melting extends along a direction surrounding the axis of the through hole and is provided within the accommodating hole.

[0009] Optionally, the air passage further includes a diameter-changing hole connected between the receiving hole and the through hole, and the diameter of the diameter-changing hole gradually increases in a direction away from the movable membrane.

[0010] Optionally, the aperture of the air passage gradually increases in size in a direction away from the movable membrane, and the blocking member is disposed within the air passage before melting.

[0011] Optionally, the top cover component further includes a flow guide member disposed in the air passage, and the blocking member before melting is disposed on the flow guide member, and after melting and cooling and solidifying to form the blocking member, it seals the air passage together with the flow guide member, and the flow guide member is formed with at least one flow guide hole for communicating the pressure reference chamber with the outside.

[0012] Optionally, the top cover component includes a top cover body and an intake component provided on the top cover body, the intake component includes a pump cover and a getter material provided within the pump cover, the top cover body is formed with a communication passage that communicates the pump cover with the pressure reference chamber, and a bottom end of the pump cover is provided within the communication passage; the air introduction passage includes the communication passage and a communication hole penetrating the bottom end side wall of the pump cover, the pressure reference chamber communicates with the outside through the communication passage and the communication hole in sequence, the blocking member before melting is provided on the top cover body corresponding to the communication hole, and the position of the communication hole is lower than the upper surface of the top cover body, and / or The air supply passage includes a communication passage and a gap between the bottom end of the pump cover and the head cover body, the pressure reference chamber communicates with the outside via the communication passage and the gap in sequence, and the blocking member before melting is fitted onto the outside of the pump cover and disposed on the head cover body.

[0013] Optionally, the material of the blocking member includes at least one of tin, aluminum, and silver, and has a bonding material layer on the surface of the flow guide member and / or on the inner wall of the air guide passage, and the material of the bonding material layer includes at least one of copper and nickel.

[0014] As a second aspect of the present invention, there is provided a method for manufacturing the pressure sensor described above, comprising the steps of: disposing the blocking member before melting at a position corresponding to the air introducing passage; disposing at least one unobstructed pressure sensor within the process chamber; evacuating the process chamber to reduce the gas pressure in the process chamber to less than a predetermined pressure; heating the process chamber so that the temperature within the process chamber does not fall below the predetermined melting temperature; and decreasing the temperature of the process chamber so that the blocking member melts and then solidifies to form the blocking member and block the air passage. A method for manufacturing a pressure sensor is provided.

[0015] Optionally, while evacuating the process chamber and reducing the gas pressure in the process chamber below a predetermined pressure, the method further includes heating the process chamber to a first predetermined temperature, the first predetermined temperature being less than the predetermined melting temperature.

[0016] In the pressure sensor according to the embodiment of the present invention, the top cover component, the upper base and the movable membrane form a pressure reference chamber, the top cover component forms an air passage that can communicate between the inside and outside of the pressure reference chamber, and the blocking member melts at least partially when heated to a temperature higher than a predetermined melting temperature and solidifies after cooling to seal the air passage. Therefore, the air passage can be blocked by the blocking member formed by melting and cooling and solidifying by simply evacuating the pressure reference chamber before attaching the blocking member, and heating and lowering the temperature of the pressure sensor after attaching the blocking member, and the inside of the pressure reference chamber can be isolated from the external environment to obtain a pressure sensor that can be used for pressure detection. In the manufacturing process of the pressure sensor according to the present invention, there is no need to assemble structures such as a vacuum pump and a copper tube, improving the manufacturing efficiency of the pressure sensor. In addition, compared with the copper tube blocking structure exposed to the outside, the structure of the present invention in which the blocking member at least partially melts and solidifies after cooling to seal the air passage is stronger, improving the stability of the entire structure of the pressure sensor, and further effectively avoiding gas leakage from the pressure reference chamber, ensuring the pressure detection accuracy of the pressure sensor.

[0017] In addition, multiple pressure sensors according to the present invention can simultaneously undergo the pressure reference chamber sealing process, which further improves the manufacturing efficiency of the pressure sensors. [Brief description of the drawings]

[0018] The drawings are intended to provide a further understanding of the present invention, constitute a part of the specification, and are used to interpret the present invention together with the following specific embodiments, but are not intended to limit the present invention. [Figure 1] FIG. 1 is a schematic diagram showing the structure of a conventional pressure sensor. [Diagram 2] FIG. 2 is a cross-sectional view of the pressure sensor in FIG. [Diagram 3] FIG. 2 is a schematic diagram of the state of the pressure sensor in FIG. 1 after the copper tube is cut off. [Figure 4]1 is a structural schematic diagram of a pressure sensor according to an embodiment of the present invention; [Diagram 5] FIG. 5 is a cross-sectional view of the pressure sensor of FIG. [Figure 6] 1A to 1C are schematic diagrams illustrating the principle of a method for manufacturing a pressure sensor according to an embodiment of the present invention. [Figure 7] 2 is a structural schematic diagram of a top cover portion of a pressure sensor according to an embodiment of the present invention; FIG. [Figure 8] FIG. 8 is a partially enlarged schematic diagram of region I in FIG. [Figure 9] 2 is a structural schematic diagram of a top cover portion of a pressure sensor according to an embodiment of the present invention; FIG. [Figure 10] 10 is a partially enlarged schematic view of region II in FIG. 9. FIG. [Figure 11] FIG. 4 is a schematic diagram showing a partial structure of a pressure sensor according to another embodiment of the present invention. [Figure 12] 12 is a schematic diagram showing the principle by which the molten material in FIG. 11 melts and solidifies to block the air passage. FIG. [Figure 13] FIG. 4 is a schematic diagram showing a partial structure of a pressure sensor according to another embodiment of the present invention. [Figure 14] 14 is a schematic diagram showing the principle of how the molten material in FIG. 13 melts and solidifies to block the air passage. FIG. [Figure 15] FIG. 4 is a schematic diagram showing a partial structure of a pressure sensor according to another embodiment of the present invention. [Figure 16] 16 is a schematic diagram showing the principle of how the molten material in FIG. 15 melts and solidifies to block the air passage. FIG. [Figure 17] FIG. 2 is a structural schematic diagram of an intake component in a pressure sensor according to an embodiment of the present invention; [Figure 18] FIG. 4 is a schematic diagram showing a partial structure of a pressure sensor according to another embodiment of the present invention. [Figure 19] FIG. 4 is a schematic diagram showing a partial structure of a pressure sensor according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. It should be understood that the specific embodiments described herein are used only to explain and interpret the present invention, and are not intended to limit the present invention.

[0020] 1 and 2 are schematic diagrams of the structure of a conventional pressure sensor, which includes a pressure reference chamber 100, a guide pin 300, an internal electrode 410, and a copper tube 50. The bottom opening of the pressure reference chamber 100 is sealed by a movable membrane 200, and the top is sealed by a top cover body 110. The internal electrode 410 is fixedly installed in the pressure reference chamber 100 and is parallel to and spaced apart from the movable membrane 200. One end of the guide pin 300 is connected to the internal electrode 410 and the other end penetrates to the outside of the pressure reference chamber 100. The copper tube 50 is fixedly connected to the top cover body 110 of the pressure reference chamber 100. One end of the copper tube 50 communicates with the inside of the pressure reference chamber 100 and the other end communicates with the outside.

[0021] Before the pressure sensor can be used, the gas in the pressure reference chamber 100 must first be extracted through the copper tube 50 to create a low-pressure environment inside the pressure reference chamber 100, and then the copper tube 50 must be shut off. As shown in Fig. 3, at this time, the pressure reference chamber 100 is completely shut off from the external environment, so that the low pressure inside the pressure reference chamber 100 can be maintained, and a usable pressure sensor can be obtained.

[0022] When the pressure sensor is placed in the environment to be measured, the movable membrane 200 is deformed by the pressure difference between the internal and external air pressures of the pressure reference chamber 100, which changes the distance between the movable membrane 200 and the internal electrode 410. The higher the external air pressure, the smaller the distance between the movable membrane 200 and the internal electrode 410, and the lower the external air pressure, the larger the distance between the movable membrane 200 and the internal electrode 410, and the capacitance value of the capacitance structure consisting of the movable membrane 200 and the internal electrode 410 changes. At this time, the detection circuit is electrically connected to the internal electrode 410 via the guide pin 300, and in response to the change in capacitance between the movable membrane 200 and the internal electrode 410, the gas pressure in the environment where the pressure sensor is placed can be identified, and the pressure detection function can be realized.

[0023] However, the inventor of the present invention found during research that the cut-off point of the copper tube 50 in the pressure sensor used is exposed to the outside and the tube wall is thin, which is a risk point of gas leakage, and the copper tube 50 only functions in the evacuation process, resulting in material waste. In addition, the manufacturing process of this structure is complicated, for example, first forming a through hole in the top cover body 110 and welding the copper tube 50 to the top cover body 110, then heating the pressure sensor to a high temperature to a temperature of several hundred degrees Celsius, connecting the tip of the copper tube 50 to a vacuum pump, evacuating the pressure reference chamber 100 by the vacuum pump, allowing the pressure reference chamber 100 to quickly reach a low pressure value, and then sealing the copper tube 50. In addition, in the prior art, the above-mentioned vacuum pump connection, evacuation, and sealing processes must usually be performed sequentially for each pressure sensor, so that only one product can be processed at a time, occupying a lot of production time. In addition, if the sealing of the copper tube 50 fails, it is difficult to perform secondary repairs of the product, which increases the manufacturing cost of the pressure sensor.

[0024] In order to solve the above technical problems, a pressure sensor is provided as one embodiment of the present invention. As shown in Figures 4 and 5, the pressure sensor includes a top cover component (including a top cover main body 110 and a partial structure provided thereon), an upper base 120, and a movable membrane 200, and openings are formed on both the top and bottom of the upper base 120, the top cover component seals the upper opening of the upper base 120, and the movable membrane 200 seals the bottom opening of the upper base 120. The top cover component, the upper base 120, and the movable membrane 200 together form a pressure reference chamber 100, and the pressure sensor is used to detect the gas pressure on the side of the movable membrane 200 away from the top cover component based on the state of the movable membrane 200. Specifically, the greater the external pressure of the pressure reference chamber 100, the more the movable membrane 200 is recessed inward, and the smaller the external pressure of the pressure reference chamber 100, the less the movable membrane 200 is recessed inward. Therefore, the pressure sensor can detect the gas pressure on the side of the movable membrane 200 away from the top cover component based on the changing state of the movable membrane 200.

[0025] Here, as shown in FIG. 9, the top cover component has at least one air passage 510 formed therein, the air passage 510 being for connecting the pressure reference chamber 100 with the outside, and the top cover component includes at least one closure member 521 used for sealing the air passage 510, and here, as shown in FIGS. 7 to 10, the closure member 521 at least partially melts when (the melting member 520) is heated to a temperature higher than a predetermined melting temperature and solidifies after cooling, thereby sealing the air passage 510.

[0026] In the pressure sensor according to the present invention, the top cover component is formed with an air passage 510 that can communicate between the inside and outside of the pressure reference chamber 100, and the melting member 520 is melted (or partially melted) at a high temperature, cooled and solidified, and then forms a blocking member 521, which seals the air passage 510. Therefore, by simply evacuating the pressure reference chamber 100 before the blocking member 521 is formed, and heating and lowering the temperature of the pressure sensor, the melting member 520 is melted and cooled and solidified to form the blocking member 521, thereby sealing the air passage 510, and the inside of the pressure reference chamber 100 is isolated from the external environment, and a pressure sensor that can be used for pressure detection can be obtained. In the manufacturing process of the pressure sensor according to the present invention, there is no need to assemble structures such as a vacuum pump and copper tube, which improves the manufacturing efficiency of the pressure sensor. In addition, compared with a copper tube blocking structure exposed to the outside, the structure of the present invention in which the air conduction passage 510 is sealed with the blocking member 521 formed by melting the molten member 520 and cooling and solidifying it is stronger, improving the stability of the entire pressure sensor structure, and furthermore, effectively preventing gas leakage from the pressure reference chamber 100, thereby ensuring the pressure detection accuracy of the pressure sensor.

[0027] In addition, the sealing process of the pressure reference chamber 100 for multiple pressure sensors according to the present invention can be performed simultaneously (i.e., the manufacturing is completed at the same time). Specifically, as shown in FIG. 6, multiple pressure sensors according to the present invention (where the molten member 520 is not yet melted) are placed in the same process chamber, the process chamber is evacuated to a vacuum, the gas pressure in the process chamber is lowered below a predetermined pressure, the process chamber is heated, and after the temperature inside the process chamber reaches the predetermined melting temperature, the process chamber is simply cooled down, so that the molten member 520 in the multiple pressure sensors can be solidified to form the blocking member 521 and block the corresponding air guide passage 510. This realizes the manufacturing of multiple pressure sensors according to the present invention in the same process, and further improves the manufacturing efficiency of the pressure sensors significantly.

[0028] As an optional embodiment of the present invention, the pressure sensor can detect the change in the movable membrane 200 based on an equivalent capacitance structure. Specifically, as shown in Figures 4 and 5, the pressure sensor further includes a guide pin 300 and an internal electrode 410, one end of the guide pin 300 is connected to the internal electrode 410, and the other end penetrates to the outside of the pressure reference chamber 100 and is used to connect to a detection circuit (not shown), so that the detection circuit can determine the gas pressure in the environment where the pressure sensor is placed in response to the change in capacitance between the movable membrane 200 and the internal electrode 410. That is, the position of the internal electrode 410 does not change, and the greater the pressure outside the pressure reference chamber 100, the smaller the distance between the movable membrane 200 and the internal electrode 410, and the corresponding increase in capacitance between the two; conversely, the smaller the pressure outside the pressure reference chamber 100, the larger the distance between the movable membrane 200 and the internal electrode 410, and the corresponding decrease in capacitance between the two. Therefore, the detection circuit can determine the magnitude of the gas pressure on the side of the movable membrane 200 away from the top cover component based on the magnitude of the capacitance value.

[0029] As a preferred embodiment of the present invention, as shown in Figures 4 and 5, the pressure sensor further includes a lower base 700, the top of the lower base 700 is sealed against the bottom of the upper base 120, a gas uniformity groove corresponding to the position of the movable membrane 200 is formed on the top of the lower base 700, a connecting tube is provided on the bottom of the lower base 700, and a through hole penetrating the connecting tube is formed on the bottom of the gas uniformity groove, so that the pressure sensor can be remotely connected to the gas environment to be measured via the connecting tube, and there is no need to install the pressure sensor in the gas environment to be measured.

[0030] For example, the process chamber of the gas pressure to be measured may be connected to a connecting tube of the lower base 700 via a conduit, so that the gas pressure on the side of the movable membrane 200 away from the top cover component matches the gas pressure in the process chamber to be measured, and further the gas pressure of the gas environment to be measured is remotely detected via a pressure sensor, reducing the difficulty of wiring the pressure sensor, reducing the contact area between the pressure sensor and the gas environment to be measured, and extending the service life of the pressure sensor.

[0031] As an optional embodiment of the present invention, as shown in Figures 4 and 5, the top cover component includes a top cover body 110, which seals the top opening of the upper base 120, and the top cover body 110 has an air passage 510 formed therethrough along its thickness direction, and a pre-melted blocking member 521 (i.e., melting member 520) is provided on the top cover body 110 corresponding to the air passage 510.

[0032] As an alternative embodiment of the present invention, the top cover body 110 is welded to the upper base 120 to ensure the airtightness of the pressure reference chamber 100 .

[0033] In order to ensure the structural strength of the pressure reference chamber 100, in a preferred embodiment of the present invention, the materials of the top cover body 110, the upper base 120 and the movable membrane 200 are all metallic materials.

[0034] It should be noted that the number of air conduction passages 510 may be multiple in order to improve the efficiency of suction during vacuum suction, but the number of openings in the top cover body 110 should be as small as possible in order to ensure the sealing of the pressure reference chamber 100. For example, as shown in FIG. 4, it is preferred that the top cover component has only one air conduction passage 510.

[0035] As a preferred embodiment of the present invention, as shown in FIG. 4 and FIG. 5, the top cover component further includes an intake component 600 provided in the top cover body 110, and as shown in FIG. 18, the intake component 600 includes a pump cover 610 and a getter material 620 provided in the pump cover 610, and the top cover body 110 is provided with a communication passage that communicates the pump cover 610 with the pressure reference chamber 100, and the bottom end of the pump cover 610 is provided in the communication passage and communicates with the inside of the pressure reference chamber 100. The getter material 620 can continuously absorb the gas in the pressure reference chamber 100 and maintain a low pressure state inside the pressure reference chamber 100. As an alternative embodiment of the present invention, as shown in FIG. 18, a horizontal filter 630 is provided in the pump cover 610 to prevent the getter material from falling into the pressure reference chamber 100.

[0036] As an optional embodiment of the present invention, as shown in FIG. 5 , the pressure reference chamber 100 is provided with a mounting member 400, the mounting member 400 is made of an insulating material, the periphery of the mounting member 400 has an outwardly protruding annular boss, the inner wall of the upper base 120 has an inwardly protruding annular boss surrounding the mounting member 400, the annular boss of the mounting member 400 is provided on the annular boss of the upper base 120, and the internal electrode 410 is provided on a bottom surface of the mounting member 400, for example, the internal electrode 410 may be a metal plating layer formed on the bottom surface of the mounting member 400.

[0037] Optionally, a conductive through hole is formed in the mounting member 400 along the height direction, a metal layer is formed on the upper surface of the mounting member 400 and on the inner wall of the conductive through hole, the metal layer on the upper surface of the mounting member 400 is electrically connected to the internal electrode 410 via the metal layer on the inner wall of the conductive through hole, and the guide pin 300 is electrically connected to the metal layer on the upper surface of the mounting member 400.

[0038] In order to ensure the sealing effect of blocking the air guide passage 510 after the melting member 520 melts, in a preferred embodiment of the present invention, the air guide passage 510 is a non-linear hole, and the cross-sectional dimension at any position of the air guide passage 510 is equal to or smaller than the cross-sectional dimension at the side farther from the movable membrane 200, i.e., any position is selected in the air guide passage 510, and the cross-sectional dimension at this position is equal to or smaller than the cross-sectional dimension at other positions above the selected position. That is, the hole diameter of the air guide passage 510 tends to decrease from top to bottom, which ensures that the flow direction of the melting member 520 after melting is downward along the air guide passage 510, and prevents the melting member 520 from flowing diffusively to the top cover body 110 after melting, and further ensures that the melting member 520 blocks the air guide passage 510. In addition, the hole diameter of the air guide passage 510 is contracted at the bottom, which can effectively improve the surface tension of the liquid surface at the bottom when the molten material 520 flows downward after melting, thereby effectively preventing the molten material 520 from passing through the air guide passage 510 and falling into the pressure reference chamber 100 after melting, and further ensures the sealing effect of closing the air guide passage 510 after the molten material 520 is melted.

[0039] In a preferred embodiment of the present invention, the minimum aperture of the air guide passage 510 is less than 2 millimeters, so as to ensure that the surface tension of the bottom liquid surface is sufficiently large when the molten material 520 flows to the position, and the molten material 520 in the liquid state can be positioned within the air guide passage 510.

[0040] In some embodiments of the present invention, the melting member 520 may be provided directly on the top cover body 110 at a position corresponding to the air passage 510 .

[0041] In order to ensure the stability of the position of the melting member 520, as a preferred embodiment of the present invention, as shown in Figs. 11 and 12, the air guide passage 510 includes a receiving hole 511 formed on the upper surface of the top cover body 110 and a through hole 512 penetrating from the bottom end of the receiving hole 511 to the bottom surface of the top cover body 110, and the hole diameter of the receiving hole 511 is larger than the hole diameter of the through hole 512. The blocking member 521 before melting (i.e., the melting member 520) extends along a direction surrounding the axis of the through hole 512 and is provided in the receiving hole 511. For example, the receiving hole 511 and the through hole 512 communicate in order from the upper surface of the top cover body 110 to the bottom surface of the top cover body 110, that is, one end of the receiving hole 511 is located on the upper surface of the top cover body 110, the other end is connected to one end of the through hole 512, and the other end of the through hole 512 is located on the bottom surface of the top cover body 110.

[0042] In the embodiment of the present invention, since the melting member 520 is provided in the receiving hole 511 with the largest hole diameter, it is possible to prevent the position of the melting member 520 from being displaced, and improve the stability of the position of the melting member 520. In addition, since the melting member 520 extends in a curved manner along the direction surrounding the axis of the through hole 512, in order to avoid changing the position of the melting member 520 when the airflow is blown out of the through hole 512 in the vacuum exhaust process and affecting the fluency of the melting member 520 flowing into the through hole 512, this can be made to avoid the through hole 512 with the smallest hole diameter in the orthogonal projection on the radial cross section of the through hole 512.

[0043] In some embodiments of the present invention, the melting member 520 may be a sheet-like member, or may be a strip-like member extending in a curved manner, for example, curved in a "C" shape around the axis of the through hole 512. In order to improve the circumferential uniformity of the force received between the melting member 520 and the air guide passage 510 and ensure the positional stability of the melting member 520, in a preferred embodiment of the present invention, the shape of the blocking member 521 (i.e., the melting member 520) before melting is annular.

[0044] In order to improve the fluidity of the molten material 520 flowing downward through the air guide passage 510 after it has melted, as a preferred embodiment of the present invention, as shown in Figures 7, 8 and 10, the air guide passage 510 further includes a diameter-changing hole 513 connected between the accommodating hole 511 and the through hole 512, and the hole diameter of the diameter-changing hole 513 gradually increases in the direction away from the movable membrane 200, thereby making the transition between the accommodating hole 511 and the through hole 512 smoother, improving the fluidity of the molten material 520 flowing along the path of the accommodating hole 511, the diameter-changing hole 513 and the through hole 512 after it has melted, and further ensuring the sealing effect of blocking the air guide passage 510 after the molten material 520 has melted.

[0045] In another preferred embodiment of the present invention, as shown in Figures 13 to 16, the hole diameter of the air conducting passage 510 gradually increases in the direction away from the movable membrane 200, and the blocking member 521 (i.e., the molten member 520) before melting is provided inside the air conducting passage 510, that is, the hole diameter of the air conducting passage 510 gradually changes along the height direction, thereby reducing the ridge and step structure on the inner wall of the air conducting passage 510, and further improving the fluidity of the molten member 520 flowing downward along the air conducting passage 510 after it has melted, and ensuring the sealing effect of closing the air conducting passage 510 after the molten member 520 has melted.

[0046] In some embodiments of the present invention, as shown in Figures 13 and 14, the hole diameter of the air passage 510 does not change with the rate of height change (the amount of change in hole diameter corresponding to each fixed height change), i.e., the air passage 510 is formed as a tapered hole.

[0047] Alternatively, in some embodiments of the present invention, the rate at which the diameter of the air passage 510 changes with height may vary along the height direction, for example, as shown in Figures 15 and 16, the rate at which the diameter of the air passage 510 changes with height may decrease and then increase, thereby forming a variable diameter hole having an "S" shaped cross-sectional profile.

[0048] In order to improve the connection strength between the molten member 520 and the inner wall of the air guide passage 510 and ensure the sealing effect of the molten member 520 to the pressure reference chamber 100, in a preferred embodiment of the present invention, the inner surface of the air guide passage 510 can be treated to increase its surface area. For example, the inner wall of the air guide passage 510 can be processed with a female thread or a structure similar to a thread, or the inner wall of the air guide passage 510 can be frosted, surface etched, etc., to increase the surface area of ​​the inner wall of the air guide passage 510, and further increase the contact area between the inner wall of the air guide passage 510 and the molten member 520, thereby improving the connection strength between the molten member 520 and the top cover body 110 and ensuring the sealing effect of the molten member 520 to the pressure reference chamber 100.

[0049] In order to further ensure the sealing effect of blocking the air passage 510 after the molten member 520 melts, in a preferred embodiment of the present invention, as shown in FIG. 17, the top cover component further includes a flow guide member 530 arranged in the air passage 510, and the blocking member 521 before melting (i.e., the molten member 520) is arranged in the flow guide member 530, and after melting, cooling and solidifying to form the blocking member 521, it seals the air passage 510 together with the flow guide member 530, and at least one flow guide hole is formed in the flow guide member 530 to connect the pressure reference chamber 100 to the outside.

[0050] In an embodiment of the present invention, the top cover body 110 of the pressure reference chamber 100 is further provided with a guiding member 530, which guides the molten member 520 after it melts, and at the same time, the molten member 520 melts and seals the air guide passage 510 together with the guiding member 530. Therefore, the guiding member 530 can improve the coupling performance and connection strength between the molten member 520 and the air guide passage 510, and can ensure the sealing effect of closing the air guide passage 510 after the molten member 520 melts.

[0051] In addition, to prevent the molten element 520 from completely blocking the air passage 510 and preventing the gas in the pressure reference chamber 100 from flowing out smoothly, the flow guide element 530 can play a supporting role for the blocking element 521 (i.e., the molten element 520) before it is melted.

[0052] In a preferred embodiment of the present invention, the flow guide member 530 is formed with a plurality of flow guide holes, for example, the flow guide member 530 may be formed as a porous part such as a mesh or a porous part, which can ensure that the gas in the pressure reference chamber 100 flows out smoothly, and at the same time, prevent the molten member 520 from dropping into the pressure reference chamber 100. In addition, after the molten member 520 melts, the porous flow guide member 530 can provide a larger surface tension to prevent the molten member 520 in a liquid state from flowing downward into the pressure reference chamber 100. In addition, the porous flow guide member 530 can form a stronger bond with the molten member 520 after it solidifies, thereby improving the reliability of the product.

[0053] In order to improve the flexibility of the processing and manufacturing of the pressure sensor, in a preferred embodiment of the present invention, the flow guide member 530 is fixedly connected to the top cover body 110 before the melting member 520 is melted, or the flow guide member 530 is fixedly connected to the melting member 520 in advance.

[0054] For example, the flow guide member 530 may first be joined to the air passage 510 (for example, by welding the air passage 510 and the flow guide member 530 by brazing), and then the molten member 520 may melt, cool and solidify to form the blocking member 521, and then be joined to the flow guide member 530 and the air passage 510.

[0055] Alternatively, the flow guide member 530 may first be bonded to the melting member 520 (e.g., first, a small portion of the blocking member 521 is melted and solidified, and then welded to the flow guide member 530), and then the melting member 520 may be re-melted and then bonded to the flow guide member 530 and the air guide passage 510.

[0056] In addition, since the pressure sensor needs to perform high-temperature degassing (i.e., vacuum exhaust operation), the predetermined melting temperature of the melting member 520 should not be too low, and generally needs to be higher than 200°C (°C); and the melting temperature of the melting member 520 should not be too high, otherwise it will not only increase the manufacturing cost of the pressure sensor (and will need to be replaced with auxiliary equipment such as temperature measuring parts that can withstand higher temperatures), but will also be likely to cause damage to other parts in the product; generally, it should be lower than 800°C.

[0057] For example, as an optional embodiment of the present invention, the material of the blocking member 521 (i.e., the melting member 520) before melting may include at least one of low melting point metal materials such as tin, aluminum, silver, etc. Alternatively, it may include a non-metallic material such as a low melting point glass.

[0058] In order to further ensure the sealing effect of closing the air guide passage 510 after the molten member 520 melts, in a preferred embodiment of the present invention, a material film layer having good weldability and sealing property with the molten member may be provided on the surface of the flow guide member 530 or the inner wall of the air guide passage 510, thereby expanding the material selection range of the molten member 520 while ensuring the closing effect of the molten member 520 on the air guide passage 510. Specifically, a bonding material layer is provided on the surface of the flow guide member 530 and / or the inner wall of the air guide passage 510, and the material of the bonding material layer includes at least one of copper and nickel.

[0059] In an alternative embodiment of the present invention, the bonding material layer may be applied to the surface of the flow guide member 530 and / or the inner walls of the air guide passages 510 by electrolytic plating.

[0060] In order to save material costs and improve the sealing performance of the pressure reference chamber 100, in a preferred embodiment of the present invention, the air guide passage 510 corresponding to the melting member 520 may be a through-hole structure of other members in the top cover body 110 corresponding to the top cover body 110 or a through-hole structure of other members attached to the top cover body 110.

[0061] For example, as shown in FIG. 19 , the air-conducting passage includes a communication passage and a gap between the bottom end of the pump cover 610 and the top cover body 110, the pressure reference chamber 100 can be connected to the outside through the communication passage and the gap in sequence, and the blocking member 521 before melting (i.e., the melting member 520) is fitted onto the outside of the pump cover 610 and disposed in the top cover body 110.

[0062] In the embodiment of the present invention, the intake component 600 and the inside of the pressure reference chamber 100 communicate with each other through the gap between the bottom end of the pump cover 610 and the top cover body 110. During the evacuation process, gas is drawn out through the gap between the bottom end of the pump cover 610 and the top cover body 110, and the molten member 520 melts and solidifies to form the blocking member 521, which then blocks the gap between the bottom end of the pump cover 610 and the side wall of the air passage 510, thereby sealing the pressure reference chamber 100.

[0063] In order to improve the flow of gas during the evacuation process, as a preferred embodiment of the present invention, as shown in FIG. 19, the air guide passage 510 further includes a communication hole 611 penetrating the side wall of the pump cover 610 and adjacent to the bottom end of the pump cover 610, the side wall of the pump cover 610 is formed with a communication hole 611 penetrating the side wall along the thickness direction, the pressure reference chamber 100 can communicate with the outside through the communication passage and the communication hole 611 in sequence, and the pressure reference chamber 100 communicates with the outside through the communication passage and the gap between the bottom end of the pump cover 610 and the top cover body 110 in sequence, the blocking member 521 before melting (i.e., the melting member 520) is provided on the top cover body 110 corresponding to the communication hole, and the position of the communication hole is lower than the upper surface of the top cover body.

[0064] Alternatively, the bottom end of the pump cover 610 may be fixedly connected to the top cover body 110 in advance (e.g., by welding), that is, there is no gap between the bottom end of the pump cover 610 and the top cover body 110, the air guide passage 510 only includes a communication passage and a communication hole 611 that penetrates the side wall of the pump cover 610 and is close to the lower end of the pump cover 610, the pressure reference chamber 100 communicates with the outside sequentially through the communication passage and the communication hole 611, the pre-melted blocking member 521 (i.e., the melting member 520) is provided on the top cover body 110 corresponding to the communication hole, and the position of the communication hole is lower than the upper surface of the top cover body.

[0065] In a second aspect of the present invention, there is provided a method for manufacturing a pressure sensor, the method comprising the steps of:

[0066] Step S1: The blocking member 521 before melting (ie, the melting member 520) is placed at a position corresponding to the air introducing passage 510.

[0067] Step S2: Placing at least one pressure sensor according to the present invention in the process chamber.

[0068] Step S3: The process chamber is evacuated to reduce the gas pressure in the process chamber to a value lower than a predetermined pressure.

[0069] Step S4: The process chamber is heated so that the temperature inside the process chamber does not fall below the predetermined melting temperature.

[0070] Step S5: The temperature of the process chamber is lowered so that the melting member 520 melts and then solidifies to form the blocking member 521 that blocks the corresponding air passage.

[0071] In the manufacturing method of the pressure sensor according to the present invention, the top cover component of the pressure sensor is formed with an air passage 510 that can communicate between the inside and outside of the pressure reference chamber 100, and the melting member 520 corresponding to the position of the air passage 510 is heated to at least partially melt, and the melting member 520 that is at least partially melted by cooling is solidified to seal the air passage 510. Therefore, the pressure reference chamber 100 is evacuated before the blocking member 521 is formed, and the pressure sensor is heated and cooled, and the melting member 520 is melted to solidify and form the blocking member 521, sealing the air passage 510, isolating the inside of the pressure reference chamber 100 from the external environment, and a pressure sensor that can be used for pressure detection is obtained. In the manufacturing process of the pressure sensor provided by the present invention, there is no need to assemble structures such as a vacuum pump and a copper tube, improving the manufacturing efficiency of the pressure sensor. In addition, compared with a copper tube blocking structure exposed to the outside, the structure of the present invention in which the air conduction passage 510 is sealed with the blocking member 521 formed by melting the molten member 520 and cooling and solidifying it is stronger, improving the stability of the entire pressure sensor structure, and furthermore, effectively preventing gas leakage from the pressure reference chamber 100, thereby ensuring the pressure detection accuracy of the pressure sensor.

[0072] Furthermore, in the manufacturing method of the pressure sensor provided in the present invention, multiple pressure sensors can undergo the sealing process of the pressure reference chamber 100 simultaneously, and multiple pressure sensors can be manufactured in the same process, which greatly improves the manufacturing efficiency of the pressure sensor.

[0073] Optionally, while evacuating the process chamber and lowering the gas pressure in the process chamber below a predetermined pressure, the manufacturing method further includes heating the process chamber to a first predetermined temperature, which is lower than the predetermined melting temperature, i.e., preheating the pressure sensor, but ensuring that the melting element 520 does not start to melt, so as to avoid premature blocking of the air passage 510. Optionally, the first predetermined temperature may be 200°C to 300°C.

[0074] Optionally, as shown in FIG. 6, the process chamber includes a chamber 10, a heater 20, and a vacuum pump 30, in which the heater 20 is provided in the chamber 10 and heats a pressure sensor in the chamber 10 (e.g., the pressure sensor can be heated by infrared light irradiation), and the vacuum pump 30 is provided in an exhaust pipe of the chamber 10 and evacuates the process chamber (i.e., extracts gas in the chamber 10).

[0075] As a third aspect of the present invention, there is provided a semiconductor processing apparatus comprising a detection circuit and a pressure sensor as provided in the present invention, the detection circuit being connected to a guide pin of the pressure sensor and responsive to a change in capacitance between a movable membrane 200 and an internal electrode 410 of the pressure sensor for determining a gas pressure in an environment in which the pressure sensor is located.

[0076] In the semiconductor processing apparatus provided in the present invention, the top cover body 110 of the pressure reference chamber 100 of the pressure sensor has an air passage 510 penetrating the top cover body 110 in the thickness direction, and the molten member 520 melts and solidifies again to form a blocking member 521 in the air passage 510, which blocks the air passage 510, improving the stability of the structure of the entire pressure sensor, effectively preventing gas leakage from the pressure reference chamber 100, and ensuring the pressure detection accuracy of the pressure sensor. In addition, a plurality of pressure sensors can be manufactured simultaneously, improving the manufacturing efficiency of the pressure sensor.

[0077] It should be understood that the above-described embodiments are merely exemplary embodiments adopted to explain the principles of the present application, and the present application is not limited thereto. Those skilled in the art can make various modifications and improvements without departing from the spirit and substance of the present application, and these modifications and improvements are also considered to fall within the scope of the claims of the present application. [Explanation of symbols]

[0078] 100: pressure reference chamber, 110: top cover body, 120: upper base, 200: movable membrane, 300: guide pin, 400: mounting member, 410: internal electrode, 510: air guide passage, 511: receiving hole, 512: through hole, 513: diameter change hole, 520: melting member, 521: blocking member, 530: flow guide member, 600: intake component, 610: pump cover, 611: communication hole, 620: getter material, 630: filter, 700: lower base

Claims

1. a pressure sensor including a top cover component, an upper base, and a movable membrane, the top and bottom of the top base being formed with openings, the top cover component sealing the top opening of the top base, the movable membrane sealing the bottom opening of the top base, the top cover component, the upper base, and the movable membrane forming a pressure reference chamber together, the pressure sensor being used to detect a gas pressure on a side of the movable membrane remote from the top cover component based on a state of the movable membrane, the top cover component being formed with at least one air introduction passage, the air introduction passage being used to communicate the pressure reference chamber with the outside, the top cover component including at least one blocking member, the blocking member being used to block the air introduction passage, the blocking member being at least partially melted when heated to a temperature higher than a predetermined melting temperature and solidifying after cooling to block the air introduction passage, Pressure sensor.

2. The top cover component includes a top cover body, the top cover body seals an upper opening of the upper base, the top cover body has an air passage penetrating therethrough in a thickness direction, and the blocking member before melting is provided on the top cover body in correspondence with the air passage.

2. The pressure sensor of claim 1.

3. The cross-sectional dimension at any position of the air guide passage is equal to or smaller than the cross-sectional dimension at the side away from the movable membrane.

3. The pressure sensor of claim 2.

4. The air guide passage includes an accommodation hole formed in the upper surface of the top cover body and a through hole penetrating from a bottom end of the accommodation hole to the bottom surface of the top cover body, the diameter of the accommodation hole is larger than the diameter of the through hole, and the blocking member before melting extends along a direction surrounding the axis of the through hole and is provided within the accommodation hole.

4. The pressure sensor of claim 3.

5. The air guide passage further includes a diameter-changing hole connected between the receiving hole and the through hole, and the diameter of the diameter-changing hole gradually increases in a direction away from the movable membrane.

5. The pressure sensor of claim 4.

6. The hole diameter of the air introducing passage gradually increases in a direction away from the movable membrane, and the blocking member before melting is provided in the air introducing passage.

4. The pressure sensor of claim 3.

7. the top cover component further comprises a flow guide member disposed in the air passage, the blocking member before melting is disposed on the flow guide member, and after melting and cooling to form the blocking member, the blocking member seals the air passage together with the flow guide member, and the flow guide member has at least one flow guide hole for communicating the pressure reference chamber with the outside.

4. The pressure sensor of claim 3.

8. the top cover component includes a top cover body and an intake component provided on the top cover body, the intake component includes a pump cover and a getter agent provided within the pump cover, the top cover body is formed with a communication passage that communicates the pump cover with the pressure reference chamber, and a bottom end of the pump cover is provided within the communication passage; the air introduction passage includes the communication passage and a communication hole penetrating the bottom end side wall of the pump cover, the pressure reference chamber communicates with the outside through the communication passage and the communication hole in sequence, the blocking member before melting is provided on the top cover body corresponding to the communication hole, and the position of the communication hole is lower than the upper surface of the top cover body, and / or The air introduction passage includes a communication passage and a gap between the bottom end of the pump cover and the top cover body, the pressure reference chamber communicates with the outside through the communication passage and the gap in sequence, and the blocking member before melting is fitted to the outside of the pump cover and disposed in the top cover body.

2. The pressure sensor of claim 1.

9. The material of the blocking member includes at least one of tin, aluminum, and silver, and a bonding material layer is provided on the surface of the flow guide member and / or on the inner wall of the air guide passage, and the material of the bonding material layer includes at least one of copper and nickel.

8. The pressure sensor of claim 7.

10. A method for producing the pressure sensor according to any one of claims 1 to 9, comprising the steps of: disposing the blocking member before melting at a position corresponding to the air introducing passage; disposing at least one unobstructed pressure sensor within the process chamber; evacuating the process chamber to reduce a gas pressure within the process chamber to less than a predetermined pressure; heating the process chamber so that the temperature within the process chamber does not fall below the predetermined melting temperature; and decreasing the temperature of the process chamber so that the blocking member melts and then solidifies to form the blocking member and block the air passage. A method for manufacturing a pressure sensor.

11. Concurrently with evacuating the process chamber and reducing the gas pressure within the process chamber below a predetermined pressure, the method further includes heating the process chamber to a first predetermined temperature, the first predetermined temperature being less than the predetermined melting temperature. The method of claim 10.

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