JP5286430B2 - Corrosion-resistant pressure type flow rate controller for the reference pressure type flow rate controller constituting the pressure control type flow rate reference device. - Google Patents

Description

  The present invention relates to an improvement of a reference pressure type flow rate controller that constitutes a pressure control type flow rate reference device used for calibration of various flow rate controllers used in semiconductor manufacturing equipment, chemical manufacturing equipment, chemical product manufacturing equipment, etc. The present invention relates to a corrosion-resistant pressure type flow rate controller for a reference pressure type flow rate controller capable of greatly improving and stabilizing the flow rate control accuracy.

  In semiconductor manufacturing apparatuses and the like, so-called calorific flow rate controllers (MFC) and pressure flow rate controllers (FCS) are often used as flow rate controllers for various process gases. In particular, the latter pressure type flow rate controller has a simple structure and has excellent characteristics such as responsiveness, measurement accuracy, service life, and maintainability, and is widely used.

By the way, these thermal flow controllers and pressure flow controllers are usually shipped to the market after performing flow rate calibration one by one using a flow standard.
On the other hand, as will be described later, the flow rate standard used for flow rate calibration is a. A method of calculating the flow rate of the fed gas from the pressure of the gas accumulated in the chamber (build-up method or ROR method), b. A method of calculating the flow rate of the gas released from the change in the chamber weight (gas flow reduction method) and c. Various standards have been developed that use a method (gravimetric method) that sends gas into the chamber and calculates the flow rate of the gas sent from the change in the weight of the chamber. After calibrating the flow rate of the flow controller related to its manufacture using a flow rate reference device independently selected by the manufacturer, the product is shipped to the end user.

  For this reason, in production facilities that use flow controllers, if the manufacturer of the flow controller is determined at the time of installation, the same flow controller from the same manufacturer must be used for refurbishing or partially updating the equipment. As a result, the flow controller of another new manufacturer cannot be easily applied, which causes a problem that the facility cost cannot be reduced. This is because the flow rate standard used for calibration varies from manufacturer to manufacturer, so even if the specifications are the same, actual flow values will vary slightly, and high-precision flow control like semiconductor manufacturing equipment. This is because it is difficult to mix and use flow controllers from different manufacturers.

There are various problems associated with the flow rate calibration of the flow rate controller due to the flow rate reference device itself.
That is, these flow rate reference devices are constructed using the normal build-up method and the weight method as described above. For example, in the former build-up method, as shown in FIG. 8, first, a gas G having a set flow rate is supplied into a chamber C having a predetermined internal volume V (l) through a flow rate controller MFC that performs flow rate calibration. From the reading of the pressure gauge P, the relationship between the supply time T and the chamber internal pressure P is obtained.
Next, from the measurement results of the supply time T and the internal pressure P as shown in FIG. 9, the pressure increase rate ΔP / Δt of the chamber internal pressure is obtained, and the following equation (1) is obtained using the pressure increase rate ΔP / Δt. The flow rate Q (sccm) of the flow rate controller MFC is calculated from the flow rate, and the read value of the flow rate controller MFC is calibrated based on this calculated value.

However, many problems still remain in this build-up method, and among them, the first problem is that it is difficult to accurately measure the gas temperature T in the chamber C.
That is, when the gas temperature T is measured at the center in the chamber C and when the gas temperature T is measured in the vicinity of the wall surface of the chamber C, the measured value of the gas temperature T is considerably different. When the temperature T changes by 1 ° C., the flow rate Q (sccm) is about 0.33% S.V. P. It will change.

  The second problem is that the measurement accuracy of the pressure gauge (baratron) P is low, and the pressure increase rate ΔP / Δt varies with each measurement. That is, the pressure gauge (Baratron) P has a unique temperature characteristic and pressure rise characteristic (linearity). Therefore, when the pressure increase range (span of pressure increase) and the pressure measurement conditions are different, the form of the curve showing the measurement results in FIG. 9 is different, and as a result, the pressure increase rate ΔP / Δt varies greatly. It will be. Further, when the flow rate of the flow rate measuring device is increased, a large chamber C is required. Conversely, when the chamber C is reduced, problems such as a long time required for measurement occur.

  The third problem is that the flow rate value (calibration flow rate) actually calculated by the equation (1) is different for each measurement. In other words, even if the experimental system, flow rate, measurement time, measurement pressure range, etc. are exactly the same, the actual flow rate value will change only by changing the flow rate range of the flow controller, resulting in high accuracy. There is a difficulty in that it is not possible to perform accurate flow rate calibration.

  FIG. 10 shows an example of the flow rate calibration test result of the flow rate controller by the build-up method. Even if the calibration flow rate is adjusted so that the flow rate error becomes zero at the flow rate setting of 100%, the flow rate setting value The results show that the error (% FS) increases as SET (%) changes.

  On the other hand, separately from the flow rate standard based on the build-up method, a gas weight reduction method is used in which the weight of the gas supply source (gas cylinder) is measured and the gas flow rate Q (sccm) is obtained from the weight reduction value. On the contrary, a flow rate reference device using a weight method in which a gas is supplied into a chamber and a gas flow rate Q (sccm) is obtained from an increase value of the chamber weight has been developed.

  However, the flow rate reference device using the gas weight loss method or the weight method has a problem that a high-precision weighing device is required, the device is large, and a long time is required for measurement.

  As described above, the flow rate reference device used for the flow rate calibration of the flow rate controller is different for each manufacturer of the flow rate controller, and the accuracy of the used flow rate reference device itself is relatively low. As a result, each time the flow controller model (manufacturer or model) to be used changes, the flow measurement value fluctuates. For example, in the field where the manufacturing process is miniaturized, such as the semiconductor manufacturing process, These slight flow calibration differences (errors) relative to the flow controller will have a significant adverse effect on the overall process.

  Further, in semiconductor manufacturing facilities and the like, a lot of corrosive gas is used as a process gas. For this reason, the flow controller is also subject to many errors due to corrosion, and there is a problem that the process is adversely affected. This also applies to the reference pressure type flow rate controller (master controller) used in the pressure control type flow rate reference device. When the flow rate calibration gas is a corrosive gas, the orifice of the master controller is used. The shape and inner diameter of the hole may change due to corrosion, or the orifice hole may be blocked by corrosion products, resulting in loss of function as a master controller.

Japanese Patent No. 3580645 JP-A-11-63265 JP 2000-137528 A

  The present invention relates to the above-described problems in the reference flow meter based on the conventional build-up method, gas weight loss method, and weight method. The accuracy of the flow standard used is low, and the structure and type of the flow standard used by each flow controller manufacturer differ, so errors between the flow controllers can adversely affect the semiconductor manufacturing process. , B. The flow rate controller with a corrosive gas flow solves problems such as a decrease in control accuracy at an early stage, and is a pressure type with high flow control accuracy and excellent operational stability. The pressure control type flow rate reference that made it possible to unify the flow rate calibration accuracy of the flow rate controller by configuring the pressure control type flow rate reference device with the flow rate controller as the reference pressure type flow rate controller (master flow rate controller) And a corrosion-resistant pressure type flow rate controller as a reference pressure type flow rate controller used therefor.

According to the first aspect of the present invention, an orifice, a control valve provided on the upstream side of the orifice, a pressure detector provided between the control valve and the orifice, and a flow rate Q from the detected pressure P _{1 of} the pressure detector are set to Q = KP ₁ (where K is a constant) with computed as made up of a flow command signal Q _S and year arithmetic and control unit for outputting a difference between the calculated flow rate signal Q as control signal Qy to the drive unit of the control valve, the orifice With the ratio of the upstream pressure P ₁ and the downstream pressure P ₂ kept below the critical pressure ratio of the controlled fluid, the orifice upstream pressure P ₁ is adjusted by opening and closing the control valve, and the fluid flow rate Q on the downstream side of the orifice In the reference pressure type flow rate controller used for the pressure control type flow rate reference device for controlling the pressure, a metal mesh is formed on the entire surface of the reference pressure type flow rate controller in contact with the fluid. The basic structure of the invention is to form a key film.

  The invention of claim 2 is the invention of claim 1, wherein the thickness of the gold plating film is 2 to 5 μm.

The invention according to claim 3 is a pressure controller for adjusting the pressure of the calibration gas from the calibration gas supply source, a volume provided on the downstream side of the pressure controller, and a flow rate controller to be calibrated provided on the downstream side of the volume. , A reference pressure flow controller connected to the downstream connection port of the flow controller to be calibrated, a volume provided downstream of the reference pressure flow controller, and a vacuum provided downstream of the volume A reference pressure type flow rate controller used for a pressure control type flow rate reference device comprising a pulling device, comprising an orifice, a control valve provided upstream of the orifice, a pressure detector provided between the control valve and the orifice, the co flow rate Q from the detected pressure P ₁ of the pressure detector as well as calculated as Q = KP 1 _(where K is a constant), the difference between the flow rate signal Q and the flow rate command signal Q _S was the arithmetic as a control signal Qy Consists of a calculation control unit that outputs to the driving section of the trawl valve, the opening and closing of the control valves the ratio between the upstream pressure P ₁ and downstream pressure P ₂ of the orifice being maintained at below the critical pressure ratio of the controlled fluid The orifice upstream pressure P ₁ is adjusted to control the fluid flow rate Q downstream of the orifice, and a gold plating film having a thickness of 2 to 5 μm is formed on the entire surface in contact with the internal fluid. To do.

  The invention of claim 4 is the invention of claim 3, wherein the thickness of the gold plating film is 1 to 3 μm.

  In the present invention, since the gold plating film is formed on the inner wall surface where the fluid inside the reference pressure type flow controller that forms the flow rate reference unit is in contact with, the corrosion resistance is improved. It can be performed more safely and with high accuracy. As a result, for example, when used for flow rate calibration of a flow rate controller for a semiconductor manufacturing apparatus, it is possible to greatly improve the quality of semiconductor products and reduce manufacturing costs.

  In addition, as a master reference flow rate controller, one or more reference pressure flow rate controllers composed of corrosion-resistant pressure type flow rate controllers are connected in parallel, and the pressure type flow rate control device is excellent. The flow control accuracy that fully utilizes the flow control accuracy is ± 0.25% S.E. P. The following flow rate reference device for flow rate calibration can be manufactured at a very low cost.

  Furthermore, since the reference pressure type flow controller consisting of a corrosion-resistant pressure type flow controller with high flow control accuracy is used as the master reference flow controller, the flow control accuracy is extremely stable even if the temperature and pressure of the fluid fluctuate. Compared to the flow rate standard based on the conventional build-up method, gas weight loss method, and weight method, the flow rate controller can be calibrated with high accuracy and stability.

1 is an overall configuration diagram of a pressure-controlled flow rate reference device including a reference pressure-type flow rate controller including a corrosion-resistant pressure-type flow rate controller according to the present invention. It is a diagram which shows the result of the flow rate accuracy test (% FS) of the reference | standard pressure type flow rate controller which consists of a corrosion-resistant pressure type flow rate controller which concerns on this invention. It is explanatory drawing of the corrosion resistance test of the reference | standard pressure type flow controller which consists of a corrosion-resistant pressure type flow controller which concerns on this invention. It is a diagram which shows the change state of the flow control error after enclosing for 24 hours of HBr gas when there is no gold plating film. It is a diagram which shows the change state of the flow control accuracy after enclosing HBr gas for 24 hours at the time of forming a gold plating film. It is a diagram which shows the change state of the flow control accuracy after enclosing HBr gas for 24 hours at the time of forming a nickel plating film. It is a diagram which shows the relationship between the frequency | count of correction | amendment of a reference | standard pressure type flow controller, and flow control accuracy. It is explanatory drawing of the flow volume calibration method based on the buildup method. It is a diagram which shows an example of the chamber pressure increase rate in the buildup method. It is a diagram which shows an example of the flow measurement accuracy based on the buildup method. The basic composition of a pressure type flow controller is shown. It is a longitudinal cross-sectional schematic diagram of a pressure type flow controller.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an overall configuration diagram of a pressure control type flow rate reference device provided with a reference pressure type flow rate control device composed of a corrosion-resistant pressure type flow rate control device according to the present invention. In FIG. 2 is a pressure controller, 3 is a volume, 4 is an N ₂ gas supply port, 5 is a thermal mass flow meter, 6 is a purge gas supply port, 7 is a purge gas discharge port, 8 is a flow rate controller to be calibrated, and 9 is corrosion resistance A reference pressure type flow controller composed of a pressure type flow controller (hereinafter referred to as a reference pressure type flow controller (master pressure type flow controller)), 10 is a volume, 11 is a connection port of a vacuuming device, and 12 is a bypass. A circuit, 13 is a connection port of a flow rate controller to be calibrated, AV _{1 to} AV ₂ 6 are on-off valves, F ₁ and F ₂ are filters, and PT is a pressure detector.

  The volumes 3 and 10 are provided to prevent a shortage of the primary supply pressure of the flow rate controller 8 to be calibrated and an increase in the secondary pressure of the reference pressure type flow rate controller (master pressure type flow rate controller) 9. In this embodiment, a tank having a capacity of 1 to 3 l is used.

  The thermal mass flow meter 5 is a preliminary flow rate controller for confirming whether or not there is a serious trouble in the reference pressure type flow rate controller (master pressure type flow rate controller) 9, and in this embodiment, Two thermal mass flowmeters of 10 SLM and 200 SCCM are used in parallel.

  The reference pressure type flow rate controller (master pressure type flow rate controller) 9 is a combination of a plurality of pressure type flow rate controllers in parallel, and the flow rate up to 10 SLM is changed to 12 reference pressure type flow rate controllers 9. Therefore, it is configured to cover.

  When performing flow rate calibration of the flow rate controller 8 to be calibrated, first, a vacuuming device, for example, a vacuum pump or a vacuum chamber (not shown) is connected to the vacuuming device connection port 11, and the reference pressure type flow rate controller 9 is connected. While evacuating the secondary side, the flow rate of the reference pressure type flow rate controller (master pressure type flow rate controller) 9 is selected so that the flow rate is close to the rated flow rate of the flow rate controller 8 to be calibrated. ~ AV22 is opened appropriately.

  Next, a calibration gas having a flow rate substantially close to the rated flow rate of the flow rate controller 8 to be calibrated is controlled from the calibration gas supply source 1 via the pressure controller 2, volume 3, and thermal mass flow meter 5. The flow of the calibrated flow rate controller 8 is calibrated by comparing the reading of the reference pressure type flow rate controller (master pressure type flow rate controller) 9 with the reading of the calibrated flow rate controller 8.

100% F. above. When the flow rate calibration in S is completed, the flow rate supplied from the calibration gas supply port 1 is adjusted, and the flow rate controllers 8 and 9 are respectively set at a predetermined set flow rate (% FS) in the same manner as described above. The flow rate of the calibrated flow rate controller 8 is calibrated.
Incidentally, during the flow calibration, a reference pressure type flow controller secondary pressure P ₂ of the (master pressure type flow controller) 9 is kept below 1/2 of the upstream pressure P _1, the reference pressure The calibration gas flowing through the orifice (not shown) of the flow rate controller 9 is in a critical state.

11 and 12 show the overall configuration of the reference pressure type flow rate controller (master pressure type flow rate controller) 9. As a pressure type flow rate controller, Japanese Patent No. 3580645, Japanese Patent Application Laid-Open No. 11-63265, etc. It is a well-known thing. That is, the flow rate Q _C = KP ₁ (K is a constant determined by the orifice QL) is calculated in the control unit H from the primary pressure P ₁ and the primary gas temperature T _{1 of} the orifice OL, and the difference from the set flow rate Qs. The opening of the flow control valve CV is adjusted so that Qy = Qs−Qc becomes zero. In addition, as a pressure type flow controller, as shown in FIG. 12, each member CV, H, P, T, OL, etc. are assembled | attached integrally.
Further, the pressure type flow rate controller is provided with a mechanism for automatically detecting clogging of the output end of the flow rate output signal and the orifice OL and so-called self-diagnosis of the flow rate (Japanese Patent Laid-Open No. 2000-137528). ).
As described above, since the pressure type flow rate controller itself is known, its detailed description is omitted here.
In addition, the pressure type flow controller has a relatively small measurement error with respect to temperature and pressure fluctuations compared to other types of flow controllers such as thermal type flow controllers, and the controller Since it is small in size and can handle various gases with the same controller, it is optimal for use as a flow control reference device.

Thus, in the reference pressure type flow controller (master pressure type flow controller) 9 used in the present invention, a gold plating film having a thickness of 2 to 5 μm is formed on the entire outer surface of the gas contact portion. Yes.
The gold plating film may be formed by any method. In the present invention, a gold plating film having a thickness of 1 to 3 μm is formed by a so-called chemical plating method.

  By the way, it is a well-known matter that a gold plating film etc. hold | maintain corrosion resistance. Therefore, the present inventors apply this known matter to a pressure type flow rate controller having an orifice as an essential component and apply gold plating to the entire surface portion of the gas contact portion, thereby providing corrosion resistance to all corrosive gases. This prevents the clogging of orifice holes due to corrosion and changes in orifice diameter, hole shape, etc., so that the flow control accuracy is always high even when corrosive gas flows. Inspired to be able to maintain.

  The reference pressure type flow rate controller (master pressure type flow rate controller) 9 according to the present invention was developed on the basis of the results of many corrosion resistance tests and flow rate control accuracy tests based on the above concept, and the gas contact part A gold plating film having a thickness of 2 to 5 μm is formed on all of the above.

Table 1 shows an example of main test items performed on the reference pressure type flow rate controller (master pressure type flow rate controller) 9 according to the present invention and its judgment criteria.
In addition, four reference pressure type flow controllers (master pressure type flow controllers) 9 were manufactured as test products.

  Tables 2 to 5 show the results of the test.

Next, the corrosion resistance test method and the test result of the reference pressure type flow controller (master pressure type flow controller) according to the present invention will be described.
Referring to FIG. 3, first, the reference pressure type flow rate controller 9 that has completed each test (accuracy confirmation test) 17 in Tables 2 to 4 is left in a clean room for 18 hours, and then N ₂ gas is used. After the cycle purge 19 is performed and the actual gas is sealed 20 for 24 hours, the cycle purge 19b using N ₂ gas is performed again, and the accuracy check test 17b is performed again. The gas flowing out from the secondary side of the gas is received by the wafer, and metal contamination existing on the wafer is inspected / confirmed 21 by the metal contamination detection device.

Each of the cycle purges 19 is continuously purged with N ₂ gas at a pressure of 0.1 MPa for 1 minute, then filled with 0.1 MPa of N ₂ gas, and then kept in a vacuum state for 10 seconds 10 times continuously. And finally purging with 0.1 MPa of N ₂ gas for 1 minute.

The corrosion test cycle shown in FIG. 3 is continuously performed by changing the actual gas to be supplied in the order of HCL, CL ₂ , HBr, and HF (4 cycles using four kinds of actual gases), and The processing operation with the same content was repeated three times.

  FIG. 4 shows a change state of flow rate control accuracy after a corrosion test in which HBr is sealed for 24 hours in a reference pressure type flow rate controller not subjected to gold plating treatment. It can be seen that an error of about 20 (% S.P.) or more is generated due to clogging of the corrosion products in the orifice, etc., after being sealed for 24 hours.

  FIG. 5 shows a change state of the flow rate control accuracy before and after the HBr gas is sealed for 24 hours when a gold plating film having a thickness of 2 μm is formed. As is clear from the comparison with FIG. When a gold plating film having a thickness of 2 to 5 μm is formed, it can be understood that the influence of corrosion by HBr gas on the flow rate control accuracy can be almost ignored at a flow rate of 20 (% SP) or more.

In the gold plating, a film thickness of about 2 to 5 [mu] m is sufficient, and even when the thickness is 5 [mu] m or more, the corrosion resistance does not increase so much and the economy is deteriorated.
Therefore, the thickness of the gold plating film is preferably selected to be 2 to 5 μm.
Similarly, the gold plating film may be formed by any method, but a chemical plating method using a plating solution is advantageous in terms of work process and can be widely applied to this type of flow controller.

  For reference, the same corrosion resistance test was performed on a reference pressure type flow rate controller in which a nickel plating film (thickness: 2 μm) was formed on the gas contact portion instead of gold plating. FIG. 6 shows the result, and it has been found that the flow rate error (% SP) decreases only about −5% in the nickel-plated film and cannot be put into practical use.

Next, the relationship between the flow rate accuracy and the number of corrections in the low flow rate region of the reference pressure type flow rate controller 9 was investigated.
In the pressure type flow rate control device, if the gas flow through the orifice is under a critical condition and the shape of the orifice (diameter or shape on the gas inlet side) is not changed, the flow rate through the orifice is the pressure P ₁ on the primary side of the orifice. Therefore, a relatively stable flow control accuracy can be basically obtained.
However, from the viewpoint of use as a reference pressure type flow rate controller (master pressure type flow rate controller) 9, higher control accuracy, for example, ± 0.25% S even in a low constant flow rate range where the set flow rate is about 1%. . Since control accuracy of P or less is desired, it was examined whether the realization was possible by repeating the correction.

  Table 6 shows the number of corrections for the reference pressure type flow rate controller 9 and the set flow rate 1% S.E. P. FIG. 7 shows the test result with the flow rate accuracy at the time of FIG.

  In Table 6 and FIG. 7, σ is the standard deviation, and the error is% F. S. Value. As is apparent from FIG. 7, by repeating the correction, ± 1 dgit = ± 0.065% F.V. S. It was found that it was possible to suppress the error to within. As a result, the reference pressure type flow rate controller 9 used for the test was ± 0.25% S.P. P. It was confirmed that the flow rate control accuracy can be sufficiently provided.

  The pressure flow control type flow rate reference device provided with the reference pressure type flow rate control device comprising the corrosion-resistant pressure type flow rate control device according to the present invention is applicable as a reference device for calibration of all kinds of flow rate control devices, and The reference pressure type flow rate controller composed of the corrosion resistant pressure type flow rate controller according to the present invention can be widely applied not only to the pressure flow rate control type flow rate reference device but also to the flow rate controller of other equipment using corrosive gas. Is.

Explanation of sign

1 Calibration gas supply port 2 Pressure controller 3 Volume 4 Filter 5 Thermal mass flow meter 6 Purge gas supply port 7 Purge gas discharge port 8 Calibrated flow rate controller 9 Corrosion resistance pressure type flow rate controller (reference pressure type flow rate controller (master Pressure type flow controller))
10 Volume 11 connecting port 12 a bypass circuit 13 to be calibrated flow controller connection port of the vacuum device AV1~AV26 off valve _F 1, _{F 2} filter PT pressure detector

Claims (4)

An orifice, a control valve provided on the upstream side of the orifice, a pressure detector provided between the control valve and the orifice, the flow rate Q from the detected pressure P ₁ of the pressure detector as Q = KP 1 _(where K is a constant) while operation is composed of a calculation control unit for outputting to the driving unit of the control valve the difference between the flow rate signal Q obtained by the arithmetic and flow command signal Q _S as a control signal Qy, the upstream pressure P ₁ and downstream of the orifice adjust the orifice upstream side pressure P ₁ the ratio of the side pressure P ₂ being maintained at below the critical pressure ratio of the controlled fluid by opening and closing of said control valve, and to control the fluid flow rate Q of the downstream side of an orifice, In the reference pressure type flow rate controller used for the pressure control type flow rate reference device, a gold plating film is formed on the entire surface of the reference pressure type flow rate controller where the fluid contacts. A corrosion-resistant pressure type flow rate controller for a reference pressure type flow rate controller constituting a pressure control type flow rate reference device.   The corrosion-resistant pressure type flow rate controller for the reference pressure type flow rate controller constituting the pressure control type flow rate reference device according to claim 1, wherein the thickness of the gold plating film is 2 to 5 μm. A pressure controller for adjusting the pressure of the calibration gas from the calibration gas supply source, a volume provided on the downstream side of the pressure controller, a connection port of the flow rate controller to be calibrated provided on the downstream side of the volume, and a calibration target Pressure composed of a reference pressure type flow controller connected to the connection port on the downstream side of the flow controller, a volume provided on the downstream side of the reference pressure type flow controller, and a vacuuming device provided on the downstream side of the volume A reference pressure type flow rate controller used for a control type flow rate reference device, comprising an orifice, a control valve provided upstream of the orifice, a pressure detector provided between the control valve and the orifice, and a detected pressure of the pressure detector from P ₁ flow Q as well as calculation as Q = KP 1 _(where K is a constant), the driving of the control valve the difference between the flow rate signal Q obtained by the arithmetic and flow command signal Q _S as a control signal Qy An arithmetic control unit and output to an orifice upstream side pressure P the ratio between the upstream pressure P ₁ and downstream pressure P ₂ being maintained at below the critical pressure ratio of the controlled fluid by opening and closing of the control valve orifice ₁ is adjusted to control the fluid flow rate Q on the downstream side of the orifice, and a pressure-controlled flow rate characterized in that a gold plating film having a thickness of 2 to 5 μm is formed on the entire surface in contact with the internal fluid. Corrosion-resistant pressure type flow controller for the reference pressure type flow controller constituting the reference unit. The corrosion-resistant pressure type flow rate controller for the reference pressure type flow rate controller constituting the pressure control type flow rate reference device according to claim 3, wherein the thickness of the gold plating film is 1 to 3 μm.

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