Vacuum measurement system

Abstract

The invention provides a vacuum measurement system. The present invention addresses the problem of suppressing a change in capacitance value caused by a change in the environment around a sensor head. An environmental sensor (131) of a vacuum measurement system according to the present invention measures the pressure or temperature around a sensor head (101). The circuit unit (102) includes a correction circuit (102a) and a measurement circuit (102b). A correction circuit (102a) corrects a capacitance value output by a sensor chip (112) housed in a sensor head (101) on the basis of a measurement result of an environmental sensor (131). A measurement circuit (102b) converts the capacitance value corrected by the correction circuit (102a) into a pressure value.

Description

Technical Field

[0001] The invention relates to a vacuum measuring system. Background Art

[0002] In a pressure sensor such as a capacitive diaphragm vacuum gauge, a sensor head containing a sensor chip including a diaphragm (diaphragm) is mounted on a pipe or the like through which a gas to be measured flows, and the deflection amount, i.e., displacement, of the diaphragm after receiving pressure is converted into a capacitance value, and a pressure value is output based on the capacitance value. The pressure sensor is widely used in industrial applications, represented by semiconductor devices, because it has little gas type dependence.

[0003] Furthermore, the process gas of the semiconductor used in the semiconductor device using the pressure sensor is easy to liquefy or solidify. Therefore, in the sensor head, the liquefied or solidified components will adhere to the pressure introduction pipe to the sensor chip or the sensor chip, thereby affecting the measurement. In order to prevent the adhesion of the process gas, the sensor head is heated. In the heating, for example, a heater is provided in a manner surrounding the outer peripheral surface of the sensor head, and the inside of the sensor head (sensor cover) is heated by the heater (Patent Document 1).

[0004] [Prior art literature]

[0005] [Patent Document]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2007-002986

[0007] [Patent Document 2] Japanese Patent Application Publication No. 2022-176611 Summary of the invention

[0008] [Problems to be solved by the invention]

[0009] However, in the above-described heating method, the pressure around the sensor head varies within the range of vacuum to atmospheric pressure. In addition, if the pressure around the sensor head varies within the range of vacuum to atmospheric pressure, the surrounding temperature may change due to adiabatic compression or adiabatic expansion. If the surrounding environment changes in this way, the output capacitance value may change due to, for example, changes in the characteristics of the sensor chip or the characteristics of the cable connecting the sensor chip to the measurement circuit.

[0010] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to suppress changes in the electrostatic capacitance value caused by changes in the environment around the sensor head.

[0011] [Technical means to solve the problem]

[0012] The vacuum measurement system of the present invention includes: a sensor head, which is arranged in a vacuum chamber and includes a sensor housing and a pressure introduction tube, the sensor housing accommodates a sensor chip that converts the displacement of a diaphragm into an electrostatic capacitance value and outputs it, the pressure introduction tube is connected to the sensor housing and guides the pressure of a measured medium to the diaphragm of the sensor chip; an environmental sensor that measures the pressure or temperature around the sensor head in the vacuum chamber; a circuit unit, which is arranged outside the vacuum chamber and includes a connector, a correction circuit and a measurement circuit, the connector is used to input the electrostatic capacitance value output by the sensor chip and the measurement result of the environmental sensor, the correction circuit is connected to the connector and corrects the electrostatic capacitance value output by the sensor chip based on the measurement result of the environmental sensor, and the measurement circuit converts the electrostatic capacitance value corrected by the correction circuit into a pressure value; and a vacuum feedthrough, which is arranged to penetrate the outer wall of the vacuum chamber on the connection path between the sensor chip and the connector.

[0013] In a configuration example of the vacuum measurement system, the environmental sensor is mounted on the sensor head.

[0014] The vacuum measurement system of the present invention includes: a sensor head, which is arranged in a vacuum chamber and includes a sensor housing and a pressure introduction tube, the sensor housing accommodates a sensor chip that converts the displacement of a diaphragm into an electrostatic capacitance value and outputs it, the pressure introduction tube is connected to the sensor housing, and guides the pressure of a measured medium to the diaphragm of the sensor chip; a circuit unit, which is arranged outside the vacuum chamber and includes a connector, a correction circuit and a measurement circuit, the connector is used to input the electrostatic capacitance value output by the sensor chip, the correction circuit is connected to the connector and corrects the electrostatic capacitance value output by the sensor chip based on the path length of the connection path between the sensor chip and the connector, and the measurement circuit converts the electrostatic capacitance value corrected by the correction circuit into a pressure value; and a vacuum feedthrough, which is arranged to penetrate the outer wall of the vacuum chamber on the connection path between the sensor chip and the connector.

[0015] In a configuration example of the vacuum measurement system, a cable is included, and the cable connects the sensor chip and the connector via a vacuum feedthrough.

[0016] In a structural example of the vacuum measurement system, it also includes: a repeater arranged in the vacuum feedthrough; a cable connecting one end of the repeater to the sensor chip; and an adapter connecting the connector to the other end of the repeater.

[0017] In a structural example of the vacuum measurement system, it also includes: a repeater, arranged in the vacuum feedthrough; a first cable, used to connect the sensor chip to one end of the repeater; a sensor adapter, connecting the first cable to one end of the repeater; a second cable, used to connect the other end of the repeater to the connector; a first adapter, connecting the second cable to the other end of the repeater; and a second adapter, connecting the second cable to the connector.

[0018] [Effects of the Invention]

[0019] According to the present invention, the electrostatic capacitance value output by the sensor chip is corrected due to the change of the environment around the sensor head, so that the change of the electrostatic capacitance value caused by the change of the environment around the sensor head can be suppressed. Alternatively, the influence of parasitic capacitance or stray capacitance related to the length of the connection path between the correction circuit and the sensor chip on the measured value can be eliminated, thereby improving the accuracy of the measured value. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a configuration diagram showing the configuration of a vacuum measurement system according to Embodiment 1 of the present invention.

[0021] Figure 2 This is a configuration diagram showing a part of the configuration of the vacuum measurement system according to the first embodiment of the present invention.

[0022] Figure 3 It is a structural diagram showing the structure of a vacuum measurement system according to Embodiment 2 of the present invention.

[0023] Figure 4 It is a structural diagram showing the structure of a vacuum measurement system according to Embodiment 3 of the present invention.

[0024] Figure 5 It is a structural diagram showing the structure of a vacuum measurement system according to a fourth embodiment of the present invention.

[0025] Figure 6 It is a structural diagram showing the structure of a vacuum measurement system according to Embodiment 5 of the present invention.

[0026] Figure 7 It is a structural diagram showing the structure of a vacuum measurement system according to Embodiment 6 of the present invention.

[0027] [Explanation of Symbols]

[0028] 101: Sensor head

[0029] 102: Circuit unit

[0030] 102a: Correction Circuit

[0031] 102b: Measurement Circuit

[0032] 103: Vacuum feedthrough

[0033] 105: Connector

[0034] 106: Cable

[0035] 111: Diaphragm

[0036] 112: Sensor chip

[0037] 113: Sensor housing

[0038] 114: Pressure inlet pipe

[0039] 121: Vacuum chamber

[0040] 122: Vacuum device

[0041] 131: Environmental Sensor

[0042] 201: Connection Path DETAILED DESCRIPTION

[0043] Hereinafter, a vacuum measurement system according to an embodiment of the present invention will be described.

[0044] [Implementation Method 1]

[0045] First, refer to Figure 1 , Figure 2 A vacuum measurement system according to Embodiment 1 of the present invention is described. The vacuum measurement system includes a sensor head 101, a circuit unit 102, a vacuum feedthrough 103, and an environmental sensor 131. The sensor head 101 is disposed in a vacuum chamber 121 connected to a vacuum device 122 as a pressure (vacuum degree) measurement object, and is in a vacuum state.

[0046] The sensor head 101 includes: a sensor housing 113 that accommodates a sensor chip 112 that converts the displacement of a diaphragm 111 into an electrostatic capacitance value and outputs it; and a pressure introduction pipe 114 that is connected to the sensor housing 113 and guides the pressure of the medium to be measured in the vacuum device 122 to the diaphragm 111 of the sensor chip 112. The pressure of the medium to be measured inside the vacuum device 122 is guided to the diaphragm 111 through the pressure introduction pipe 114. The interior of the sensor housing 113 is vacuum-sealed and set as a reference vacuum chamber. Since the sensor chip 112 is arranged inside the sensor housing 113 set as a vacuum reference chamber, the absolute pressure can be measured.

[0047] The environmental sensor 131 is installed in the vacuum chamber 121 together with the sensor head 101, and measures the pressure or temperature around the sensor head 101. Figure 1In the embodiment, the environment sensor 131 is provided separately from the sensor head 101, but it is also possible to provide a holding portion for holding the environment sensor 131 in the sensor head 101, and to install the environment sensor 131 in the holding portion. The configuration in which the environment sensor 131 is installed in the sensor head 101 makes it easier to install the environment sensor 131 in the vacuum chamber 121 (the same applies to the second and third embodiments described later). On the other hand, the circuit unit 102 provided outside the vacuum chamber 121 includes a correction circuit 102a and a measurement circuit 102b inside. The correction circuit 102a uses the measurement result of the environment sensor 131 inputted from the connector 105 via the connection path 201 and the electrostatic capacitance value outputted from the sensor chip 112, and corrects the electrostatic capacitance value outputted from the sensor chip 112 based on the measurement result of the environment sensor 131. The measurement circuit 102b converts the electrostatic capacitance value corrected by the correction circuit 102a into a pressure value.

[0048] For example, the electrostatic capacitance value can be corrected by "electrostatic capacitance value × correction value A0 + correction value B0". For example, it can be set as "correction value A0 = measurement result of environmental sensor 131 × correction value A00 + correction value A01", and set as "correction value B0 = measurement result of environmental sensor 131 × correction value B00 + correction value B01". Correction value A00, correction value A01, correction value B00, correction value B01 can be calculated for each sensor chip 112 in the production process of the product and stored in the memory of the correction circuit 102a. The correction value stored in the memory can be changed appropriately.

[0049] The vacuum feedthrough 103 is a vacuum component that has an airtight structure that allows a cable 106 for transmitting an electrical signal to pass through the inside of a vacuum chamber 121 that is maintained in a vacuum state, blocks the inflow of the atmosphere from the outside, and is provided on the outer wall of the vacuum chamber 121 that passes through the connection path 201 between the sensor chip 112 and the connector 105. In addition, in each embodiment of the vacuum measurement system of the present invention, the vacuum feedthrough 103 is preferably composed of a coaxial type vacuum feedthrough having a coaxial structure. Furthermore, the sensor chip 112 housed in the sensor housing 113 of the sensor head 101 is connected to the connector 105 of the circuit unit 102 via the cable 106 via the vacuum feedthrough 103. In addition, the environmental sensor 131 is connected to the connector 105 via the cable 106 via the vacuum feedthrough 103.

[0050] The cable 106 can be, for example, a coaxial cable. The capacitive pressure sensor needs to detect small capacitance changes, so the measured value is easily affected by parasitic capacitance or stray capacitance. In particular, it is affected by parasitic capacitance or stray capacitance in the wiring from the sensor chip 112 to the correction circuit 102a. In order to avoid these effects, a coaxial cable is used, and the sensor chip 112 is connected to the connector 105 using a core wire, and the shield wire is connected to the ground (Patent Document 2).

[0051] For example, in order to connect each of the pressure-sensing fixed electrode and the pressure-sensing movable electrode of the sensor chip 112 to the correction circuit 102a, two coaxial cables are required in one sensor head 101. In addition, when a reference electrode is used in addition to the pressure-sensing electrode, two additional coaxial cables are required because the reference fixed electrode and the reference movable electrode are further provided on the sensor chip 112, resulting in a total of four coaxial cables. However, in the above case, it is also possible to select either a case where the pressure-sensing fixed electrode and the reference fixed electrode are integrated and shared or a case where the pressure-sensing movable electrode and the reference movable electrode are integrated and shared, and when such a selection is made, three coaxial cables are required.

[0052] According to the embodiment, since the sensor chip 112 in the sensor housing 113 in the sensor head 101 is connected to the correction circuit 102a via the vacuum feedthrough 103 provided through the outer wall of the vacuum chamber 121, the interior of the vacuum chamber 121 in which the sensor head 101 is arranged can be set to a vacuum state, thereby making it possible to heat the sensor head 101. In addition, for example, when four cables are used for connection between the sensor head 101 and the circuit unit 102, one vacuum feedthrough can be used for every two cables. In addition, a plurality of cables can be bundled.

[0053] Furthermore, according to the above embodiment, the correction circuit 102 a corrects the capacitance value outputted from the sensor chip 112 based on the measurement result of the environment sensor 131 , thereby suppressing the change in the capacitance value caused by the change in the environment around the sensor head 101 .

[0054] [Implementation Method 2]

[0055] Next, refer to Figure 3 A vacuum measurement system according to Embodiment 2 of the present invention is described. The vacuum measurement system includes a sensor head 101, a circuit unit 102, a vacuum feedthrough 103, and an environmental sensor 131. These structures are the same as those of Embodiment 1. Embodiment 2 further includes a relay 107 provided in the vacuum feedthrough 103.

[0056] In the second embodiment, one end of the repeater 107 is connected to the sensor chip 112 via the cable 106. In the second embodiment, the connector 105 is connected to the other end of the repeater 107 via the adapter 108. Through these connections, the sensor chip 112 is connected to the correction circuit 102a via the connection path 201 of the cable 106-repeater 107-adapter 108-connector 105.

[0057] In Embodiment 2, the sensor head 101 and the correction circuit 102a are also connected via the vacuum feedthrough 103, so the sensor head 101 can be heated equally as in Embodiment 1. In addition, according to Embodiment 2, since a cable between the vacuum feedthrough 103 and the connector 105 is not required, there is an advantage that the total cable length of the connection path 201 can be shortened. In Embodiment 2, the correction circuit 102a also corrects the electrostatic capacitance value output by the sensor chip 112 based on the measurement result of the environmental sensor 131, so the change in the electrostatic capacitance value caused by the change in the environment around the sensor head 101 can be suppressed.

[0058] [Implementation method 3]

[0059] Next, refer to Figure 4 A vacuum measurement system according to a third embodiment of the present invention will be described. The vacuum measurement system includes a sensor head 101, a circuit unit 102, a vacuum feedthrough 103, and an environmental sensor 131. These structures are the same as those of the first embodiment.

[0060] In Embodiment 3, a repeater 107 is further included which is provided in the vacuum feedthrough 103. In Embodiment 3, one end of the repeater 107 is connected to the sensor chip 112 via the first cable 106a. A sensor adapter 109 is mounted on the end of the first cable 106a on the repeater 107 side, and the first cable 106a is connected to one end of the repeater 107 via the sensor adapter 109.

[0061] In Embodiment 3, the other end of the repeater 107 is connected to the connector 105 via the second cable 106b. The end of the second cable 106b on the repeater side is connected to the repeater 107 via the first adapter 108a. The second cable 106b is connected to the other end of the repeater 107 via the first adapter 108a. In addition, the end of the second cable 106b on the connector side is connected to the connector 105 via the second adapter 108b.

[0062] Through these connections, the sensor chip 112 is connected to the correction circuit 102a using the connection path 201 of the first cable 106a - sensor adapter 109 - repeater 107 - first adapter 108a - second cable 106b - second adapter 108b - connector 105.

[0063] In Embodiment 3, the sensor chip 112 and the correction circuit 102a are also connected via the vacuum feedthrough 103, so that the interior of the vacuum chamber 121 in which the sensor head 101 is arranged can be set to a vacuum state as in Embodiment 1, so that the sensor head 101 can be heated evenly. In addition, according to Embodiment 3, there is an advantage that when it is desired to adjust and change the connection distance between the vacuum feedthrough 103 and the connector 105 on site, the second cable 106b can be easily adjusted and changed by simply selecting a cable with an appropriate cable length. In addition, in Embodiment 3, the correction circuit 102a also corrects the electrostatic capacitance value output by the sensor chip 112 based on the measurement result of the environmental sensor 131, so that the change in the electrostatic capacitance value caused by the change in the environment around the sensor head 101 can be suppressed.

[0064] [Implementation Method 4]

[0065] Next, refer to Figure 5 A vacuum measurement system according to a fourth embodiment of the present invention is described. The vacuum measurement system includes a sensor head 101, a circuit unit 102, and a vacuum feedthrough 103. The sensor head 101 is placed in a vacuum chamber connected to a vacuum device 122 to be measured for pressure (vacuum degree), and is in a vacuum state.

[0066] The sensor head 101 includes: a sensor housing 113 that accommodates a sensor chip 112 that converts the displacement of a diaphragm 111 into an electrostatic capacitance value and outputs it; and a pressure introduction pipe 114 that is connected to the sensor housing 113 and guides the pressure of the medium to be measured to the diaphragm 111 of the sensor chip 112. The pressure of the medium to be measured inside the vacuum device 122 is guided to the diaphragm 111 through the pressure introduction pipe 114. The inside of the sensor housing 113 is vacuum-sealed and set as a reference vacuum chamber. Since the sensor chip 112 is arranged inside the sensor housing 113 set as a vacuum reference chamber, the absolute pressure can be measured.

[0067] The circuit unit 102 includes a connector 105 for inputting the electrostatic capacitance value output by the sensor chip 112, and a correction circuit 102a' and a measurement circuit 102b connected to the connector 105 to correct the input electrostatic capacitance value. The correction circuit 102a' corrects the electrostatic capacitance value output by the sensor chip 112 based on the path length of the connection path between the connector 105 or the correction circuit 102a' and the sensor chip 112. The measurement circuit 102b converts the electrostatic capacitance value corrected by the correction circuit 102a' into a pressure value.

[0068] For example, the electrostatic capacitance value can be corrected by "electrostatic capacitance value × correction value A0 + correction value B0". For example, it can be set to "correction value A0 = path length × correction value A00 + correction value A01", and set to "correction value B0 = path length × correction value B00 + correction value B01". The path length can be set to the length of the cable 106 described later, for example. The path length (the length of the cable 106) can be stored in the memory of the correction circuit 102a'. In addition, the correction value A00, the correction value A01, the correction value B00, and the correction value B01 can be calculated for each sensor chip 112 in the production process of the product, and stored in the memory of the correction circuit 102a'. The path length and correction value stored in the memory can be changed as appropriate.

[0069] The vacuum feedthrough 103 is a vacuum component that has an airtight structure for allowing a cable 106 for transmitting an electrical signal to pass into a vacuum chamber 121 maintained in a vacuum state, blocks the inflow of atmosphere from the outside, and is arranged on the outer wall of the vacuum chamber 121 on a connection path 201 that passes through the sensor chip 112 and the connector 105.

[0070] The cable 106 can be, for example, a coaxial cable. The capacitive pressure sensor needs to detect minute capacitance changes, so the measured value is easily affected by parasitic capacitance or stray capacitance. In particular, it is affected by parasitic capacitance or stray capacitance in the wiring from the sensor chip 112 to the correction circuit 102a'. In order to avoid these effects, a coaxial cable is used, and the core wire is used to connect the sensor chip 112 to the connector 105, and the shield wire is connected to the ground (Patent Document 2).

[0071] For example, in order to connect each of the pressure-sensing fixed electrode and the pressure-sensing movable electrode of the sensor chip 112 to the correction circuit 102a', two coaxial cables are required in one sensor head 101. In addition, when a reference electrode is used in addition to the pressure-sensing electrode, two additional coaxial cables are required because the reference fixed electrode and the reference movable electrode are further provided on the sensor chip 112, resulting in a total of four coaxial cables. However, in the above case, it is possible to select either a case where the pressure-sensing fixed electrode and the reference fixed electrode are integrated and shared or a case where the pressure-sensing movable electrode and the reference movable electrode are integrated and shared, and when such a selection is made, three coaxial cables are required.

[0072] According to the embodiment, since the sensor chip 112 in the sensor housing 113 of the sensor head 101 is connected to the correction circuit 102a' via the vacuum feedthrough 103 provided through the outer wall of the vacuum chamber 121, the interior of the vacuum chamber 121 in which the sensor head 101 is arranged can be set to a vacuum state. In addition, for example, when four cables are used for connection between the sensor head 101 and the circuit unit 102, one vacuum feedthrough can be used for every two cables. In addition, a plurality of cables can be bundled.

[0073] Furthermore, according to the embodiment, the correction circuit 102a' corrects the electrostatic capacitance value output by the sensor chip 112 based on the path length of the connection path between the connector 105 or the correction circuit 102a' and the sensor chip 112, thereby eliminating the influence of parasitic capacitance or stray capacitance related to the path length of the connection path on the measured value, thereby improving the accuracy of the measured value.

[0074] [Implementation method 5]

[0075] Next, refer to Figure 6 A vacuum measurement system according to a fifth embodiment of the present invention will be described. The vacuum measurement system includes a sensor head 101, a circuit unit 102, and a vacuum feedthrough 103. These structures are the same as those of the fourth embodiment. In the fifth embodiment, a relay 107 provided in the vacuum feedthrough 103 is further included.

[0076] In the fifth embodiment, one end of the repeater 107 is connected to the sensor chip 112 via the cable 106. In the fifth embodiment, the connector 105 is connected to the other end of the repeater 107 via the adapter 108. Through these connections, the sensor chip 112 is connected to the correction circuit 102a' via the connection path 201 of the cable 106-repeater 107-adapter 108-connector 105.

[0077] In the fifth embodiment, the sensor head 101 and the measuring circuit 102b are also connected via the vacuum feedthrough 103, so that the interior of the vacuum chamber 121 in which the sensor head 101 is arranged can be set to a vacuum state as in the fourth embodiment, thereby allowing the sensor head 101 to be heated evenly. In the fifth embodiment, the correction circuit 102a' also corrects the electrostatic capacitance value output by the sensor chip 112 based on the path length of the connection path between the connector 105 or the correction circuit 102a' and the sensor chip 112, so that the influence of parasitic capacitance or stray capacitance related to the path length of the connection path on the measured value can be eliminated, thereby improving the accuracy of the measured value.

[0078] [Implementation Method 6]

[0079] Next, refer to Figure 7 A vacuum measurement system according to a sixth embodiment of the present invention will be described. The vacuum measurement system includes a sensor head 101, a circuit unit 102, and a vacuum feedthrough 103. These structures are the same as those of the fourth embodiment.

[0080] In Embodiment 6, a repeater 107 is further included which is provided in the vacuum feedthrough 103. In Embodiment 6, one end of the repeater 107 is connected to the sensor chip 112 via the first cable 106a. A sensor adapter 109 is mounted on the end of the first cable 106a on the repeater 107 side, and the sensor adapter 109 is connected to the repeater 107. The first cable 106a is connected to one end of the repeater 107 via the sensor adapter 109.

[0081] In addition, in Embodiment 6, the repeater 107 is connected to the connector 105 via the second cable 106b. The end of the second cable 106b on the repeater 107 side is connected to the repeater 107 via the first adapter 108a. The second cable 106b is connected to the other end of the repeater 107 via the first adapter 108a. In addition, the end of the second cable 106b on the connector 105 side is connected to the connector 105 via the second adapter 108b.

[0082] Through these connections, the sensor chip 112 is connected to the measurement circuit 102 b using a connection path 201 of first cable 106 a - sensor adapter 109 - repeater 107 - first adapter 108 a - second cable 106 b - second adapter 108 b - connector 105 .

[0083] In the sixth embodiment, the sensor chip 112 and the measurement circuit 102b are also connected via the vacuum feedthrough 103, so that the interior of the vacuum chamber 121 in which the sensor head 101 is arranged can be set to a vacuum state as in the fourth embodiment, thereby allowing the sensor head 101 to be heated evenly. In the sixth embodiment, the correction circuit 102a' also corrects the electrostatic capacitance value output by the sensor chip 112 based on the path length of the connection path between the connector 105 or the correction circuit 102a' and the sensor chip 112, so that the influence of parasitic capacitance or stray capacitance related to the path length of the connection path on the measured value can be eliminated, thereby improving the accuracy of the measured value.

[0084] As described above, according to the present invention, the electrostatic capacitance value output by the sensor chip is corrected due to the change in the environment around the sensor head, so that the change in the electrostatic capacitance value caused by the change in the environment around the sensor head can be suppressed. Alternatively, the influence of parasitic capacitance or stray capacitance related to the length of the connection path between the correction circuit and the sensor chip on the measured value can be eliminated, thereby improving the accuracy of the measured value.

[0085] In addition, the present invention is not limited to the above-described embodiments, and it is obvious that a person having ordinary knowledge in the art can implement various modifications and combinations within the technical concept of the present invention.

Claims

1. A vacuum measurement system, comprising: A sensor head is disposed in a vacuum chamber and includes a sensor housing and a pressure introduction tube, wherein the sensor housing accommodates a sensor chip that converts a displacement of a diaphragm into an electrostatic capacitance value and outputs the value, and the pressure introduction tube is connected to the sensor housing and guides the pressure of a measured medium to the diaphragm of the sensor chip; an environmental sensor for measuring pressure or temperature around the sensor head in the vacuum chamber; a circuit unit, disposed outside the vacuum chamber and comprising a connector, a correction circuit, and a measurement circuit, wherein the connector is used to input the electrostatic capacitance value output by the sensor chip and the measurement result of the environmental sensor, the correction circuit is connected to the connector and corrects the electrostatic capacitance value output by the sensor chip based on the measurement result of the environmental sensor, and the measurement circuit converts the electrostatic capacitance value corrected by the correction circuit into a pressure value; and The vacuum feedthrough is provided to penetrate the outer wall of the vacuum chamber on a connection path between the sensor chip and the connector.

2. The vacuum measurement system according to claim 1, characterized in that: The environmental sensor is installed on the sensor head.

3. A vacuum measurement system, comprising: A sensor head is disposed in a vacuum chamber and includes a sensor housing and a pressure introduction tube, wherein the sensor housing accommodates a sensor chip that converts a displacement of a diaphragm into an electrostatic capacitance value and outputs the value, and the pressure introduction tube is connected to the sensor housing and guides the pressure of a measured medium to the diaphragm of the sensor chip; a circuit unit disposed outside the vacuum chamber and comprising a connector, a correction circuit, and a measurement circuit, wherein the connector is used to input an electrostatic capacitance value output by the sensor chip, the correction circuit is connected to the connector and corrects the electrostatic capacitance value output by the sensor chip based on a path length of a connection path between the sensor chip and the connector, and the measurement circuit converts the electrostatic capacitance value corrected by the correction circuit into a pressure value; and The vacuum feedthrough is provided to penetrate the outer wall of the vacuum chamber on a connection path between the sensor chip and the connector.

4. The vacuum measurement system according to any one of claims 1 to 3, comprising: A cable connects the sensor chip and the connector via the vacuum feedthrough.

5. The vacuum measurement system according to any one of claims 1 to 3, further comprising: A repeater, disposed in the vacuum feedthrough portion; A cable, connecting one end of the repeater to the sensor chip; as well as An adapter connects the connector to the other end of the repeater.

6. The vacuum measurement system according to any one of claims 1 to 3, further comprising: A repeater, disposed in the vacuum feedthrough portion; A first cable, used to connect the sensor chip to one end of the repeater; a sensor adapter, connecting the first cable to one end of the repeater; a second cable, used to connect the other end of the repeater to the connector; a first adapter, connecting the second cable to the other end of the repeater; as well as The second adapter connects the second cable to the connector.

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