Vacuum gauge module and vacuum degree measuring method

Abstract

The invention provides a vacuum gauge module and a vacuum degree measuring method. The vacuum gauge module comprises a vacuum gauge unit, a control unit and a detection unit. The vacuum gauge unit comprises a first vacuum gauge and a second vacuum gauge, the first vacuum gauge has a first measuring range, the second vacuum gauge has a second measuring range, and the first measuring range is different from the second measuring range; the detection unit is connected with the vacuum gauge unit through the control unit, and the connection mode of the detection unit and the vacuum gauge unit is switched through the control unit, so that the detection unit at least detects electric signals of the first vacuum gauge or the second vacuum gauge. According to the MEMS Pirani vacuum gauge, the problem that the MEMS Pirani vacuum gauge in the prior art cannot perform accurate measurement in a wide vacuum range is solved.

Description

Technical Field

[0001] This invention relates to the field of vacuum measurement technology, and in particular to a vacuum gauge module and a vacuum measurement method. Background Technology

[0002] With the rapid development of advanced manufacturing technologies, vacuum technology has begun to be widely used in industry and scientific research, and has received great attention in various industries such as inertial navigation, automotive electronics, chemical pharmaceuticals, and semiconductor manufacturing.

[0003] MEMS Pirani vacuum gauges, based on the principle of thermal conductivity measurement and combined with microelectromechanical systems (MEMS) technology, feature high precision, high reliability, and miniaturization, enabling accurate vacuum measurements. However, the effective range of MEMS Pirani vacuum gauges is limited, and optimization of the effective range through manufacturing process improvements and geometric design is also limited. Therefore, how to perform accurate vacuum measurement over a wide vacuum range is a technical problem that those skilled in the art urgently want to solve. Summary of the Invention

[0004] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a vacuum gauge module and a vacuum degree measurement method to solve the problem that the MEMS Pirani vacuum gauge in the prior art cannot perform accurate measurements over a wide vacuum range.

[0005] To achieve the above and other related objectives, the present invention provides a vacuum gauge module, including a vacuum gauge unit, a control unit, and a detection unit;

[0006] The vacuum gauge unit includes a first vacuum gauge and a second vacuum gauge, wherein the first vacuum gauge has a first range, the second vacuum gauge has a second range, and the first range and the second range are different.

[0007] The detection unit is connected to the vacuum gauge unit through the control unit. The control unit switches the connection mode between the detection unit and the vacuum gauge unit so that the detection unit can detect the electrical signal of at least the first vacuum gauge or the second vacuum gauge.

[0008] Optionally, the control unit includes a first control group and a second control group. The first vacuum gauge is connected to the detection unit through the first control group, and the second vacuum gauge is connected to the first vacuum gauge through the second control group. The connection mode of the detection unit, the first vacuum gauge, and the second vacuum gauge is switched through the first control group and the second control group, so that the detection unit detects the electrical signals of the first vacuum gauge, the second vacuum gauge, or a composite vacuum gauge. The composite vacuum gauge includes the first vacuum gauge and the second vacuum gauge in series.

[0009] Optionally, the first vacuum gauge and the second vacuum gauge are Pirani vacuum gauges, and the detection unit detects the electrical signals of the corresponding vacuum gauges based on a Wheatstone bridge.

[0010] Optionally, the first vacuum gauge includes a first equivalent resistance, the second vacuum gauge includes a second equivalent resistance, the first control group includes a first switch and a second switch, the second control group includes a third switch and a fourth switch, and the detection unit includes a first matching resistor, a second matching resistor, a third matching resistor, a fourth matching resistor, a constant voltage source, and a detection section.

[0011] The positive terminal of the constant voltage source is connected to the common terminal of the first switch via the first matching resistor and to the common terminal of the second switch via the second matching resistor, and the negative terminal is connected to the reference ground.

[0012] The first terminal of the first switch is connected to the common terminal of the third switch via the first equivalent resistor, and the second terminal is directly connected to the common terminal of the third switch.

[0013] The first terminal of the second switch is connected to the common terminal of the fourth switch via the third matching resistor, and the second terminal is directly connected to the common terminal of the fourth switch.

[0014] The first terminal of the third switch is connected to the reference ground via the second equivalent resistor, and the second terminal is directly connected to the reference ground;

[0015] The first terminal of the fourth switch is connected to the reference ground via the fourth matching resistor, and the second terminal is directly connected to the reference ground.

[0016] The detection section is connected to the common terminal of the first switch and the second switch, and generates a detection signal by detecting the electrical signal of the corresponding vacuum gauge.

[0017] Optionally, the detection section includes an amplifier, a first transistor, a second transistor, and a load resistor;

[0018] The amplifier's first input terminal is connected to the common terminal of the first switch, its second input terminal is connected to the common terminal of the second switch, and its output terminal is connected to the emitters of the first transistor and the second transistor.

[0019] The base of the first transistor is connected to the common terminal of the first switch and the base of the second transistor, and the collector is connected to its base;

[0020] The collector of the second transistor is connected to reference ground via the load resistor and outputs the detection signal.

[0021] Optionally, the first vacuum gauge further includes a first reference resistor, and the second vacuum gauge further includes a second reference resistor. The first reference resistor is used to replace the third matching resistor, and the second reference resistor is used to replace the fourth matching resistor. The first reference resistor and the second reference resistor are thermistors.

[0022] Optionally, the first vacuum gauge and the second vacuum gauge are integrated on the same substrate using MEMS technology. A first cavity and a second cavity are formed on the substrate. The first equivalent resistance of the first vacuum gauge is suspended above the first cavity, and the second equivalent resistance of the second vacuum gauge is suspended above the second cavity. The cross-sectional areas of the first cavity and the second cavity are different.

[0023] Optionally, when the first vacuum gauge includes a first reference resistor and the second vacuum gauge includes a second reference resistor, the first reference resistor and the second reference resistor are directly disposed on the substrate, wherein each resistor is fabricated simultaneously.

[0024] Optionally, the vacuum gauge module further includes a power supply unit connected to the vacuum gauge unit and the detection unit to supply power to the vacuum gauge unit and the detection unit.

[0025] The present invention also provides a vacuum degree measurement method based on the vacuum gauge module described above, comprising: selecting a vacuum gauge with a corresponding range to measure the vacuum degree of the environment under test according to the vacuum range of the environment under test, and detecting the electrical signal of the corresponding vacuum gauge to realize the vacuum degree measurement.

[0026] As described above, the vacuum gauge module and vacuum degree measurement method of the present invention integrate vacuum gauges with different ranges into the same module to provide multiple ranges of vacuum gauges by switching them with a switch, and measure the vacuum degree by detecting minute changes in the corresponding vacuum gauges, thereby achieving accurate measurement of vacuum degree under different vacuum environments using vacuum gauges with different ranges. Attached Figure Description

[0027] Figure 1 The diagram shown is a structural schematic of the vacuum gauge module.

[0028] Figure 2 This is a circuit diagram of a vacuum gauge module.

[0029] Figure 3 This is another circuit diagram of a vacuum gauge module.

[0030] Figure 4 The diagram shown is a structural schematic of a vacuum gauge unit.

[0031] Figure 5 This is a schematic diagram of another structure of the vacuum gauge unit.

[0032] Figure 6 The diagram shows the operation of the vacuum gauge module under different vacuum environments.

[0033] Component designation explanation

[0034] 100 Vacuum Gauge Module

[0035] 110 Vacuum gauge unit

[0036] 111 First Vacuum Gauge

[0037] 112 Second Vacuum Gauge

[0038] 120 Control Unit

[0039] 121 First Control Group

[0040] 122 Second Control Group

[0041] 130 detection units

[0042] 131 Detection Section

[0043] 140 power supply units Detailed Implementation

[0044] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0045] Please see Figures 1 to 6 It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Therefore, the illustrations only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the shape, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0046] like Figures 1-3 As shown, this embodiment provides a vacuum gauge module 100, including a vacuum gauge unit 110, a control unit 120, and a detection unit 130; further, it also includes a power supply unit 140.

[0047] The vacuum gauge unit 110 includes a first vacuum gauge 111 and a second vacuum gauge 112. Of course, it is also feasible to include more vacuum gauges, but due to limitations such as process size, designing more vacuum gauges is not very meaningful. Among them, the first vacuum gauge 111 has a first range, and the second vacuum gauge 112 has a second range, and the first range and the second range are different; by using vacuum gauges with different ranges, accurate measurement of vacuum level under different vacuum environments can be achieved.

[0048] As an example, the first vacuum gauge 111 and the second vacuum gauge 112 are Pirani vacuum gauges; wherein, the first vacuum gauge 111 includes a first equivalent resistance R. S1 The second vacuum gauge 112 includes a second equivalent resistance R. S2 In an alternative example, the first vacuum gauge 111 and the second vacuum gauge 112 are integrated on the same substrate using MEMS technology, such as... Figure 4 As shown. Furthermore, a first cavity and a second cavity are formed on the substrate, and the first equivalent resistance R... S1 Suspended above the first cavity, the second equivalent resistance R S2 It is suspended above the second cavity, and the cross-sectional areas of the first cavity and the second cavity are different.

[0049] In this design, the first cavity serves as the gas-sensitive area of ​​the first vacuum gauge 111, and the second cavity serves as the gas-sensitive area of ​​the second vacuum gauge 112. Since the gas-sensitive area is directly related to the measurement range, different gas-sensitive areas are designed to give the two vacuum gauges different measurement ranges. Assuming the area of ​​the gas-sensitive area of ​​the first vacuum gauge 111 is S1 and the area of ​​the gas-sensitive area of ​​the second vacuum gauge 112 is S2, then we can design S1 > S2, R... S1 ≈R S2 .

[0050] In one implementation, the first vacuum gauge 111 and the second vacuum gauge 112 are implemented using a sandwich structure of meandering resistors. The sandwich structure includes, from bottom to top, a support layer, a resistance layer, an electrode layer, and a protective layer. The support layer is set above the cavity by a cantilever beam. The meandering metal in the resistance layer serves as an equivalent resistor. The electrode layer includes electrode terminals set at both ends of the equivalent resistor. The protective layer is set at least above the support layer. The material of the resistance layer is titanium.

[0051] Of course, in other examples, the first vacuum gauge 111 may also include a first reference resistor R. R1 The second vacuum gauge 112 may also include a second reference resistor R. R2 At this time, the first reference resistor R R1 and the second reference resistor R R2 Directly mounted on the substrate and used as a thermistor to suppress temperature drift, such as... Figure 5As shown; among them, the two reference resistors and the two equivalent resistors are manufactured simultaneously and are made of the same material, titanium.

[0052] The detection unit 130 is connected to the vacuum gauge unit 110 through the control unit 120. The control unit 120 switches the connection mode between the detection unit 130 and the vacuum gauge unit 110 so that the detection unit 130 can detect the electrical signal of at least the first vacuum gauge 111 or the second vacuum gauge 112.

[0053] As an example, the control unit 120 includes a first control group 121 and a second control group 122. The first vacuum gauge 111 is connected to the detection unit 130 through the first control group 121, and the second vacuum gauge 112 is connected to the first vacuum gauge 111 through the second control group 122. The connection mode of the detection unit 130, the first vacuum gauge 111 and the second vacuum gauge 112 is switched through the first control group 121 and the second control group 122, so that the detection unit 130 can detect the electrical signals of the first vacuum gauge 111, the second vacuum gauge 112 or the composite vacuum gauge. The composite vacuum gauge includes the first vacuum gauge 111 and the second vacuum gauge 112 in series.

[0054] The above example provides three ranges of vacuum gauges. In application, different ranges of vacuum gauges can be switched according to actual needs to measure the vacuum level in different vacuum environments, so as to achieve accurate measurement of the environmental vacuum level in a wide vacuum range. Of course, in other examples, it is also feasible for the detection unit to be connected to the first vacuum gauge 111 and the second vacuum gauge 112 respectively through a set of control groups (the two vacuum gauges can be regarded as parallel). However, in this case, the detection unit 130 can only detect the electrical signal of the first vacuum gauge 111 or the second vacuum gauge 112, and cannot detect the electrical signal of the composite vacuum gauge.

[0055] Since the first vacuum gauge 111 and the second vacuum gauge 112 are Pirani vacuum gauges, the detection unit 130 detects the electrical signals of each vacuum gauge, such as the current value, based on a Wheatstone bridge.

[0056] In one implementation, the first vacuum gauge 111 includes a first equivalent resistance R. S1 The second vacuum gauge 112 includes a second equivalent resistance R. S2 The first control group 121 includes a first switch S1 and a second switch S2; the second control group 122 includes a third switch S3 and a fourth switch S4; the detection unit 130 includes a first matching resistor R1, a second matching resistor R2, a third matching resistor R3, a fourth matching resistor R4, and a constant voltage source V. B And testing section 131.

[0057] like Figure 2 As shown, constant pressure source V BThe positive terminal is connected to the common terminal of the first switch S1 via the first matching resistor R1 and to the common terminal of the second switch S2 via the second matching resistor R2; the negative terminal is connected to the reference ground; the first terminal of the first switch S1 is connected to the first equivalent resistor R... S1 The common terminal of the third switch S3 is connected, and the second terminal is directly connected to the common terminal of the third switch S3; the first terminal of the second switch S2 is connected to the common terminal of the fourth switch S4 via the third matching resistor R3, and the second terminal is directly connected to the common terminal of the fourth switch S4; the first terminal of the third switch S3 is connected via the second equivalent resistor R... S2 The first terminal of the fourth switch S4 is connected to the reference ground, and the second terminal is directly connected to the reference ground. The first terminal of the fourth switch S4 is connected to the reference ground via the fourth matching resistor R4, and the second terminal is directly connected to the reference ground. The detection section 131 is connected to the common terminal of the first switch S1 and the second switch S2, and detects the electrical signals of each vacuum gauge to generate detection signals, such as generating voltage values ​​based on the detected current values.

[0058] The detection section 131 includes an amplifier OP, a first transistor Q1, a second transistor Q2, and a load resistor R. L The amplifier OP's first input terminal (e.g., inverting input terminal) is connected to the common terminal of the first switch S1, and its second input terminal (e.g., non-inverting input terminal) is connected to the common terminal of the second switch S2. The output terminal is connected to the emitters of the first transistor Q1 and the second transistor Q2. The base of the first transistor Q1 is connected to the common terminal of the first switch S1 and the base of the second transistor Q2, and its collector is connected to its base. The collector of the second transistor Q2 is connected via a load resistor R. L Connect to the reference ground and output a detection signal.

[0059] In other implementations, the first vacuum gauge 111 also includes a first reference resistor R. R1 The second vacuum gauge 112 also includes a second reference resistor R. R2 At this time, such as Figure 3 As shown, a first reference resistor R is used. R1 Replace the third matching resistor R3 and use the second reference resistor R R2 Replace the fourth matching resistor R4; where the first reference resistor R R1 and the second reference resistor R R2 It is a thermistor; by keeping the resistor temperature consistent with the ambient temperature, it prevents temperature drift and reduces measurement errors caused by changes in ambient temperature.

[0060] It should be noted that the above only shows one connection relationship between the switch and the resistor. In fact, any connection scheme that allows different range vacuum gauges to be selected by switching the switch should be applicable to this embodiment. Simple adjustments to the positions of the switch and the resistor have no substantial impact on the implementation of this embodiment.

[0061] The power supply unit 140 is connected to the vacuum gauge unit 110 and the detection unit 130, and is used to supply power to the vacuum gauge unit 110 and the detection unit 130.

[0062] Accordingly, this embodiment also provides a vacuum degree measurement method, including the following steps; wherein, the vacuum degree measurement method is implemented based on the vacuum gauge module 100 described above.

[0063] The method includes: selecting a vacuum gauge with a corresponding range to measure the vacuum degree of the environment under test according to the vacuum range of the environment under test, and detecting the electrical signal of the corresponding vacuum gauge to realize the vacuum degree measurement.

[0064] by Figure 3 Taking the circuit shown as an example, the operation of the vacuum gauge module 100 when measuring the vacuum level under different vacuum environments is as follows: Figure 6 As shown, the area S1 of the gas-sensitive region of the first vacuum gauge 111 is larger than the area S2 of the gas-sensitive region of the second vacuum gauge 112. The first and second ends of the first switch S1, the second switch S2, the third switch S3, and the fourth switch S4 are respectively denoted as 1 to 8.

[0065] For low vacuum environments, switch S1 is switched to position 1, switch S2 to position 3, switch S3 to position 6, and switch S4 to position 8. The first vacuum gauge 111 is selected to measure the ambient vacuum level. At this time, the first matching resistor R1, the second matching resistor R2, and the first equivalent resistance R... S1 and the first reference resistor R R1 Construct a Wheatstone bridge and detect the first equivalent resistance R on the Wheatstone bridge. S1 The resistance changes and generates a corresponding voltage output, enabling accurate detection of vacuum levels in low-vacuum environments.

[0066] For a high vacuum environment, switch S1 is switched to position 2, switch S2 to position 4, switch S3 to position 5, and switch S4 to position 7. The second vacuum gauge 112 is then selected to measure the ambient vacuum level. At this time, the first matching resistor R1, the second matching resistor R2, and the second equivalent resistance R... S2 and the second reference resistor R R2 Construct a Wheatstone bridge and detect the second equivalent resistance R on the Wheatstone bridge. S2 The resistance changes and generates a corresponding voltage output, enabling accurate detection of vacuum levels in high vacuum environments.

[0067] For a wide vacuum range, switch S1 is switched to position 1, switch S2 to position 3, switch S3 to position 5, and switch S4 to position 7. The composite vacuum gauge is then selected for environmental vacuum measurement. At this time, the first matching resistor R1, the second matching resistor R2, and the composite equivalent resistance (i.e., the first equivalent resistance R...) are... S1 With the second equivalent resistance R S2 The sum of the two reference resistors and the composite reference resistor (i.e., the first reference resistor R) R1 With the second reference resistor R R2 The sum of these components forms a Wheatstone bridge, which detects changes in the resistance of the composite equivalent resistance on the Wheatstone bridge and generates a corresponding voltage output, enabling accurate detection of vacuum levels in a wide vacuum range environment.

[0068] In practical applications, the ambient vacuum level is not constant for different application scenarios. If the ambient vacuum level changes, when measuring the vacuum level using the vacuum gauge module 100 in this embodiment, the output of the corresponding vacuum gauge can be used to determine whether the current ambient vacuum level has exceeded the range of the vacuum gauge. If so, a vacuum gauge with a different range can be selected to complete the measurement of the current ambient vacuum level. Measuring the vacuum level under different vacuum environments using vacuum gauges with different ranges helps to improve measurement accuracy.

[0069] In summary, the vacuum gauge module and vacuum degree measurement method of the present invention integrate vacuum gauges with different ranges into the same module, providing multiple ranges of vacuum gauges through switching. Vacuum degree measurement is achieved by detecting minute changes in the corresponding vacuum gauges, thus realizing accurate measurement of vacuum degree under different vacuum environments using vacuum gauges with different ranges. Therefore, the present invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0070] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A vacuum gauge module, characterized in that, Includes a vacuum gauge unit, a control unit, and a detection unit; The vacuum gauge unit includes a first vacuum gauge and a second vacuum gauge, wherein the first vacuum gauge has a first range, the second vacuum gauge has a second range, and the first range and the second range are different. The detection unit is connected to the vacuum gauge unit through the control unit. The control unit switches the connection mode between the detection unit and the vacuum gauge unit so that the detection unit can detect the electrical signal of at least the first vacuum gauge or the second vacuum gauge.

2. The vacuum gauge module according to claim 1, characterized in that, The control unit includes a first control group and a second control group. The first vacuum gauge is connected to the detection unit through the first control group, and the second vacuum gauge is connected to the first vacuum gauge through the second control group. The connection mode of the detection unit, the first vacuum gauge and the second vacuum gauge is switched through the first control group and the second control group, so that the detection unit detects the electrical signals of the first vacuum gauge, the second vacuum gauge or a composite vacuum gauge. The composite vacuum gauge includes the first vacuum gauge and the second vacuum gauge in series.

3. The vacuum gauge module according to claim 2, characterized in that, The first vacuum gauge and the second vacuum gauge are Pirani vacuum gauges, and the detection unit detects the electrical signals of the corresponding vacuum gauges based on a Wheatstone bridge.

4. The vacuum gauge module according to claim 3, characterized in that, The first vacuum gauge includes a first equivalent resistance, the second vacuum gauge includes a second equivalent resistance, the first control group includes a first switch and a second switch, the second control group includes a third switch and a fourth switch, and the detection unit includes a first matching resistor, a second matching resistor, a third matching resistor, a fourth matching resistor, a constant voltage source, and a detection section. The positive terminal of the constant voltage source is connected to the common terminal of the first switch via the first matching resistor and to the common terminal of the second switch via the second matching resistor, and the negative terminal is connected to the reference ground. The first terminal of the first switch is connected to the common terminal of the third switch via the first equivalent resistor, and the second terminal is directly connected to the common terminal of the third switch. The first terminal of the second switch is connected to the common terminal of the fourth switch via the third matching resistor, and the second terminal is directly connected to the common terminal of the fourth switch. The first terminal of the third switch is connected to the reference ground via the second equivalent resistor, and the second terminal is directly connected to the reference ground; The first terminal of the fourth switch is connected to the reference ground via the fourth matching resistor, and the second terminal is directly connected to the reference ground. The detection section is connected to the common terminal of the first switch and the second switch, and generates a detection signal by detecting the electrical signal of the corresponding vacuum gauge.

5. The vacuum gauge module according to claim 4, characterized in that, The detection section includes an amplifier, a first transistor, a second transistor, and a load resistor; The amplifier's first input terminal is connected to the common terminal of the first switch, its second input terminal is connected to the common terminal of the second switch, and its output terminal is connected to the emitters of the first transistor and the second transistor. The base of the first transistor is connected to the common terminal of the first switch and the base of the second transistor, and the collector is connected to its base; The collector of the second transistor is connected to reference ground via the load resistor and outputs the detection signal.

6. The vacuum gauge module according to claim 4, characterized in that, The first vacuum gauge further includes a first reference resistor, and the second vacuum gauge further includes a second reference resistor. The first reference resistor is used to replace the third matching resistor, and the second reference resistor is used to replace the fourth matching resistor. The first reference resistor and the second reference resistor are thermistors.

7. The vacuum gauge module according to any one of claims 1 to 6, characterized in that, The first vacuum gauge and the second vacuum gauge are integrated on the same substrate using MEMS technology. A first cavity and a second cavity are formed on the substrate. The first equivalent resistance of the first vacuum gauge is suspended above the first cavity, and the second equivalent resistance of the second vacuum gauge is suspended above the second cavity. The cross-sectional areas of the first cavity and the second cavity are different.

8. The vacuum gauge module according to claim 7, characterized in that, When the first vacuum gauge includes a first reference resistor and the second vacuum gauge includes a second reference resistor, the first reference resistor and the second reference resistor are directly disposed on the substrate, wherein each resistor is fabricated simultaneously.

9. The vacuum gauge module according to claim 1, characterized in that, The vacuum gauge module also includes a power supply unit, which is connected to the vacuum gauge unit and the detection unit to supply power to the vacuum gauge unit and the detection unit.

10. A method for measuring vacuum degree based on the vacuum gauge module according to any one of claims 1 to 9, characterized in that, include: Based on the vacuum range of the environment to be tested, a vacuum gauge with the corresponding range is selected to measure the vacuum degree of the environment to be tested, and the electrical signal of the corresponding vacuum gauge is detected to realize the vacuum degree measurement.

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