KR0126580B1 - Apparatus for correcting of a vacuum sensor - Google Patents

Abstract

The apparatus for correcting vacuum sensors which are used in a vacuum equipment, comprises: a polygonal pillar chamber(1) having a cylindrical space in the interior thereof and a polygonal pillar shape in the exterior thereof; and standard sensors(5,6) and correcting sensors(7,8) each attached on a chamber side plate(2) of the polygonal pillar chamber(1) to be placed with the same partial pressure as each other, the standard sensors(5,6) and correcting sensors(7,8) each disposed to be in an equal shape, equal distance and equal position.

Description

Vacuum Sensor Compensation Device Using Polyhedral Column Vacuum Chamber

1 is a schematic diagram of a vacuum sensor correction apparatus using a polyhedral cylinder vacuum chamber.

2 is an assembly state of the vacuum sensor correction apparatus using a polyhedral cylinder vacuum chamber.

3 is a characteristic diagram of a standard pressure sensor.

4 is a characteristic diagram before and after correction of a correction sensor.

5 is a comparison of the characteristics of the output difference with the standard sensor after correction of the correction sensor.

* Description of the symbols for the main parts of the drawings *

1: polyhedral pillar chamber 2: chamber side plate

3: chamber upper plate 4: pneumatic isolation valve

5,6: Standard sensor 7,8: Calibration sensor

9: Pneumatic isolation valve for purge and vent 10: Manual adjustment needle valve

11: Flexible connection bellows 12: Shut off gate valve

13 pressure control valve 14 vibration compensator

15: turbo pump 16: auxiliary pump

17 exhaust port 18 voltage measuring instrument

19: 2-channel display device 20: Pressure valve regulator

21: pneumatic valve selection switch box 22: signal stability and channel selector

The present invention relates to a vacuum sensor correction apparatus using a multi-column resonant chamber as a device for correcting a vacuum sensor (capacitance manometer, piranha gauge, thermocouple gauge, hot cathode ion gauge, cold cathode ion gauge) used in vacuum equipment.

The pressure sensor used in most vacuum equipments changes the electrical signal characteristic, which is the output of the sensor with respect to the input pressure, after a certain period of time. This change is largely a change in the zero point and a change in the slope within the pressure sensing range.

When the product is produced using the changed vacuum sensor, it has an undesirable effect on the reliability and productivity of the product. In order to reduce this effect, it is necessary to periodically calibrate the pressure sensor of the vacuum equipment to any standard.

Among the conventional vacuum sensor correction devices currently commercially available are MKS's Portable Vacuum Standard (PVS) and Rittenstein Balzers' PSK, but the former MKS's chamber processing type uses a manual valve on a cylindrical vacuum tube. It is intended to use, and there is a problem in that the partial position of the standard sensor and the calibration sensor is located at different distances from the exhaust port of the chamber.

Therefore, the above products have a difficulty in reprocessing the chamber when additional standards or correction sensors are to be attached.

In the latter Balzers model, the PSK is a cylindrical dome shaped chamber with the sensor port facing up, and a limited number of standard and calibration sensors can be attached.

However, the above products have a disadvantage that the vacuum chamber must be made into the atmosphere because there is no pneumatic valve that blocks the pressure between the chamber and the sensor when the standard sensor or correction sensor is attached or added. There is a problem in that the shape of the chamber must be changed when adding.

In order to solve the above problems, the present invention implements the correction of sensors having a vacuum pressure sensing range of 1.0 × 10 ^-6 torr at atmospheric pressure by using a polyhedral pillar chamber among various vacuum pressure sensors used in a vacuum equipment at a production site. It is an object of the present invention to provide a vacuum sensor correction apparatus using a polyhedral pillar resonant chamber.

In order to achieve the above object, in the present invention, a capacitance manometer or a precision standard sensor, which is a standard sensor for precisely measuring a certain pressure range, is attached to the polyhedral column vacuum chamber from the bottom exhaust port 17 of the polyhedral column chamber 1. It is characterized in that the correction sensor can be attached to the isoform, isoposition, equidistance so that the sensor to be calibrated has the same partial pressure as the standard sensor.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a conceptual diagram of the vacuum sensor correction apparatus of the present invention, Figure 2 is an assembly diagram.

In the present invention, the standard sensor (5), (6) and the correction sensor (7), (8) is placed on the same partial pressure by using the polyhedral column chamber (1), the inside of the polyhedral column chamber (1) of the cylindrical shape It was processed into a space and the outside was formed into a polyhedral column.

Pneumatic isolation valve (9) and manual adjustment needle valve (10) for purge and vent used for chamber pressure control are attached to the center of chamber top (3), and connected to the center of chamber bottom with vacuum pump. Since there is an exhaust port 17, the same partial pressure can be obtained at the same height on each side of the chamber even when supplying gas for pressure control or gas exhaust of the chamber.

In addition, the pneumatic isolation valve 4 is located between the standard sensors 5, 6 and the correction sensors 7, 8 and the polyhedral column chamber on each side so that the unused sensors can be isolated from the chamber. It was. This is to ensure that the sensor is kept in a stable state to minimize the zero shift of the standard sensor or the calibration sensor. That is, the basic shape of the outside of the chamber (1) located in the center has a polyhedral pillar shape, and on each side thereof, the standard sensor (5,6) and the correction sensor (7,8) from the side plate (2) of the vacuum chamber (1) Pneumatic isolating valve (4) is attached to isolate the arbitrary. At this time, the standard sensor and the calibration sensor are placed in the isomorphism, equidistance, and equiposition so that the same partial pressure is achieved.

Exhaust of the polyhedral column chamber 1 is connected to the exhaust port 17 of the chamber 1, a flexible connection bellows 11, a shut-off gate valve 12, a pressure control valve 13, a vacuum compensator 14, a turbopump (5), the auxiliary pump 16 is assembled.

Reference numeral 18 denotes a voltage force measuring instrument, 19 is a two-channel display device, 20 is a pressure valve regulator, 21 is a pneumatic valve selection switch box, and 22 is a signal stability and channel selector.

It looks at the operation and effects of the present invention configured as described above.

Air is used to drive the various valves 4, 9 and 12 attached to the apparatus, and the drive signal is connected to be driven by the solenoid valve by operating the corresponding switch of the switch box 21.

Nitrogen is used to control the pressure of the polyhedral column chamber and purge and vent the chamber, and the flow sequence of the nitrogen is a polyhedral column chamber (1) through a manual adjustment needle valve (10), a purge and band pneumatic isolation valve (9). ) Is injected.

The vacuum measurement of the chamber uses a coercometer 18 to measure the approximate vacuum in the range 1.0 × 10 ⁻¹⁰ torr from the atmosphere. The low-vacuum pressure sensor of this high pressure measuring instrument 18 uses a Piranny sensor, which measures 1.0 × 10 ⁻³ torr from the atmosphere.

The high vacuum pressure sensor uses a cold cathode ion sensor, which measures the approximate vacuum in the range from 1.0 × 10 ^-3 to 1.0 × 10 ^-10 torr. The vacuum degree measured by this voltage measuring instrument 18 is used as the basic pressure of the vacuum chamber when calibrating the correction sensor using this apparatus.

The standard sensor used for calibration has a capacitance manometer with excellent linearity in the detection range. The maximum sensing ranges of these sensors are 1000, 100, 10, 1, and 0.1torr, respectively, and this standard sensor outputs a voltage of 0 volts at a pressure below 1.0 × 10 ^-6 torr, which is the base pressure. The maximum sensing range outputs 10 volts.

Pressure control of the vacuum chamber is connected to the exhaust port 17 of the chamber while injecting a small amount of nitrogen gas through the manual control needle valve 10 and the purge and vent pneumatic isolation valve 9 connected to the gas inlet of the chamber. It is made by properly adjusting the angle of the disc control blade in the pressure control valve (13).

To explain this in more detail, the variable resistance for pressure regulation in the pressure valve regulator 20 is selected as the desired pressure, and the standard sensors 5 and 6 of the corresponding pressure are selected in the signal stability and channel selector 22.

In the standard sensor, the chamber vacuum degree at that time is measured and the pressure state is sent to the two-channel digital display device 19 so as to read the pressure. This measured value is fed back to the pressure regulating regulator 20 to adjust the pressure by finely adjusting the angle of the disc blade in the pressure regulating valve 13 again in comparison with the selected value.

The actual calibration of the calibration sensor used in the vacuum equipment is carried out by attaching the calibration sensors (7) and (8) to the pneumatic isolation valve (4) attached to the chamber, selecting a standard sensor suitable for the calibration sensor range, and then The calibration is performed to match the output of the standard sensor with varying chamber pressures. The following is a description of an embodiment in which the vacuum sensor used in the actual equipment is corrected using the vacuum sensor correcting apparatus of the present invention.

Tables 1 and 3 are characteristic tables and characteristic charts of the output voltage versus pressure of a standard sensor having a maximum sensing pressure range of 10torr attached to the apparatus of the present invention.

[Figure 1]

The standard sensor having a maximum sensing range of 10torr used in the pressure calibration experiment according to the present invention has the output characteristics as shown in Table 1, and this characteristic is shown in FIG.

As can be seen from the above diagrams and figures, the standard sensor has an output voltage corresponding to pressure in the sensing range of 0 to 10torr (1 to 1) between 0 and 10V, and the percentage error is +0.038 to -0.035%, which is very accurate. It can be seen that it has characteristics.

The calibration sensor used in the experiment was selected as the sensor used in the equipment of the production site and compared with the standard sensor was measured while increasing the output voltage value of the calibration sensor in the chamber pressure range of 0 to 10 torr by 1 tor.

[Figure 2] Comparison between before and after calibration of calibration sensor (voltage: pressure)

As can be seen from the results of Table 2, the calibration sensor has a variation of 0.088 volts at the zero point when compared with the standard sensor, and 10.272 volts is 0.2664 volts higher at the output of 10 volts of the standard sensor.

Since the actual process of the equipment using the selected calibration sensor is performed in the range of 50mtorr ~ 1torr, it can be seen that the variation of the zero voltage of the sensor attached to the equipment and the error in this range directly affected the process.

4 is a characteristic diagram of an output voltage showing the above result.

5 is a measurement of the output voltage difference between the calibration sensor and the standard sensor before and after calibration.

As shown in this result, the zero point variation of the calibration sensor disappears after correction and the percentage error is also reduced to the range of +0.126 to -0.074 when compared to the error before correction. It can be seen that the linearization is close to the output voltage value within the sensing range of the sensor and the output voltage value with the standard sensor.

The vacuum sensor correction device using the polyhedral column chamber has the same partial pressure in the chamber by placing the standard sensor and correction sensor at equidistant distances, so it can be more precisely corrected than the existing products. At the time of attachment, the pressure in the chamber was maintained in a vacuum so that it could be easily replaced.

Therefore, when the sensor is calibrated using the apparatus of the present invention, it is determined that the pressure sensor output signal in the vacuum equipment is stabilized, and as a result, the stability and productivity of the process using the vacuum are increased.

As described above, in the present invention, a device capable of correcting various pressure sensors that are essentially attached to an apparatus using a vacuum may be implemented using a polyhedral pillar vacuum chamber, thereby more accurately correcting at the same partial pressure. In addition, each chamber side plate (2) is equipped with a pneumatic isolation valve (4) to attach a standard sensor for each sensing area and open and close it as necessary, so that the standard sensor or correction sensor is equal to the pressure state of the vacuum chamber In addition to being detachable, these sensors can be placed under their most stable state, thereby providing convenience and stability in use.

In addition, since the injection port for air or nitrogen gas required for pressure control of the vacuum chamber is made in the center of the upper surface of the chamber, the partial pressure generated during the injection may have the same value at the same position, thereby increasing the stability and productivity of the process using the vacuum. It is a very useful technique that can be done.

Claims (4)

A device for calibrating vacuum pressure sensors (capacitance manometer, Piranha gauge, thermocouple gauge, hot cathode ion gauge, cold cathode ion gauge) used in vacuum equipment, which forms an inner space into a cylindrical space and an outer polyhedral cylinder shape. A polyhedral cylinder vacuum chamber (1); In the chamber side plate 2 of the polyhedral column vacuum chamber 1, standard sensors 5, 6 and correction sensors 7, 8 are attached to the same partial pressure, and the standard sensor 5 , (6) and the correction sensor (7), (8) is a vacuum sensor correction device using a polyhedral pillar vacuum chamber, characterized in that it is configured to be placed in the same shape, equidistant, equidistant position such that the same partial pressure. According to claim 1, The upper chamber 3 of the chamber (1) in the center of the nitrogen gas injection port for the pressure control in the vacuum chamber (1) as a purge (purge) and vent (pneumatic isolation valve for vent) ( 9) and the manual adjustment needle valve (10) is attached, the exhaust port 17 is connected to the vacuum pump at the center of the bottom of the chamber (1) is installed even when supplying gas for pressure control or gas exhaust of the chamber (1) A vacuum sensor correction device using a polyhedral cylinder vacuum chamber, characterized in that the same partial pressure is always obtained at the same height on each side of the cylinder. 2. The sensor according to claim 1, wherein the standard sensors (5), (6) and correction sensors (7), (8), which are provided in each chamber side plate (2) of the vacuum chamber (1), are arbitrarily provided by a pneumatic isolation valve (4). A sensor for calibrating a vacuum sensor using a polyhedral pillar vacuum chamber, characterized in that the intermittent sensors can be used to isolate unused sensors from the chamber. The standard sensors (5), (6) and correction sensors (7) and (8) of claim 1 or 3, which are provided in each chamber side plate (2) of the vacuum chamber (1), can be attached in multiple stages. Vacuum sensor correction device using a polyhedral pillar vacuum chamber, characterized in that to be easily switched when adding the correction sensor.