Integrated full-scale high-precision flow controller and flow measurement and control method

Abstract

The invention relates to the field of flow control, in particular to an integrated full-scale high-precision flow controller and a flow measurement and control method. The integrated full-range high-precision flow controller comprises a fluid conveying flow path, a control valve and a main control chip, the fluid conveying flow path is provided with at least two flow measuring parts which are different in measuring range and connected in parallel, and each flow measuring part comprises a sensor and a flow resistance structure which are used in cooperation. A measuring part switching assembly is arranged at an inlet of the branch flow path where each flow measuring part is located; the control valve is installed on the fluid conveying flow path and connected with the measuring part switching assembly in series. The main control chip is connected with the flow measuring part, the measuring part switching assembly and the control valve. The flow can be accurately measured, so that the flow is accurately controlled, the requirement of customers for high precision of small-flow process gas is met, full-scale high-precision flow control is met, the integration degree is high, and the structure is compact.

Description

Technical Field

[0001] The present invention relates to the field of flow measurement and control, and in particular to an integrated full-range high-precision flow controller and a flow measurement and control method. Background Art

[0002] A mass flow controller (MFC) is a device used to control gas flow and plays an important role in the semiconductor manufacturing process. MFC can accurately control the flow of gas to ensure stability and repeatability in the semiconductor production process. The semiconductor manufacturing process requires the use of a large amount of gases, such as hydrogen, nitrogen, argon, oxygen and chlorine. The flow control accuracy of these gases is very critical because they directly affect the manufacturing of chips. In processes such as chemical vapor deposition (CVD), the accuracy of the mass flow controller directly affects the thickness and uniformity of the deposited film. In the etching process, inaccurate flow control may cause uneven etching, residue or damage to the wafer surface, affecting the performance and yield of the device.

[0003] Defects and shortcomings of the existing technology: At present, the mainstream mass flow controller brands in the semiconductor industry have difficulty guaranteeing accuracy in the small range. For example, when the set flow rate is >20%FS (FullScall), the accuracy of Brooks' GF120 series is ±1.0%SP (SetPoint); when the set flow rate is ≤ 20%FS, the accuracy is ±0.2%FS. However, the flow rate can be controlled within the range of 2-100%FS, that is, the control capability of the valve is far greater than the range that can guarantee the flow measurement accuracy.

[0004] This is because the current MFC generally adopts a technical solution consisting of a control valve, a flow measurement component and a main control circuit. The pressure flow measurement component includes a pressure sensor and a flow resistance structure installed in series on the pipeline along the fluid delivery direction. The thermal flow measurement component includes a thermal sensor and a flow resistance structure installed in parallel on the pipeline. The main control circuit integrates a control program and a flow calculation program. When the flow rate is lower than a certain range, the pressure difference or heat generated by the gas passing through the flow measurement component is too small, which ultimately leads to a large error in the calculated flow rate. That is, the flow measurement component is affected by its own performance, which makes the accuracy of the MFC small range section insufficient.

[0005] When a certain process gas needs to use both high and low flow rates, the inventor has to use two MFCs with different ranges to control the two flow rates respectively in order to ensure the flow control accuracy, so as to meet the process requirements for flow accuracy. Therefore, when designing the equipment, not only is it necessary to design an additional gas line, which increases the cost of related components required on the gas line (such as diaphragm valves, PT, pressure regulating valves, etc.), but it also increases the volume of the entire gas cabinet.

[0006] Therefore, there is an urgent need to design a mass flow controller with compact structure and high precision over the entire range. Summary of the invention

[0007] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide an integrated full-range high-precision flow controller, which can accurately measure the flow rate and thus accurately control the flow rate, meet the customer's high-precision requirements for small-flow process gases, meet the full-range high-precision flow control, and has high integration and compact structure.

[0008] In order to solve the above technical problems, the technical solution of the present invention is: an integrated full-range high-precision flow controller, comprising: The fluid delivery flow path is equipped with at least two flow measurement parts with different ranges and connected in parallel with each other, the flow measurement parts include sensors and flow resistance structures used in conjunction with each other, and a measurement part switching component is provided at the entrance of the branch flow path where each flow measurement part is located; A control valve, installed on the fluid delivery path and connected in series with the measuring part switching assembly; The main control chip is respectively connected to the flow measurement unit, the measurement unit switching component and the control valve.

[0009] Furthermore, at least a part of the flow measurement part is a single-range pressure measurement part, and its sensor is a pressure sensor, and the pressure sensor and the flow resistance structure used in conjunction with it are installed in series.

[0010] Furthermore, the single-range pressure measuring unit also includes an outlet pressure sensor, which is installed in the rear channel of the flow resistance structure of the single-range pressure measuring unit and is connected to the main control chip.

[0011] Furthermore, at least a part of the flow measurement part is a single-range thermal measurement part, and its sensor is a thermal sensor, and the thermal sensor and the flow resistance structure used in conjunction with it are installed in parallel.

[0012] Furthermore, at least a portion of the flow measurement unit is a multi-range measurement unit, in which: The sensor is configured with at least two sensors of different ranges. When the sensor is a pressure sensor, each sensor is connected in series in sequence. When the sensor is a thermal sensor, each sensor is connected in parallel with each other, and a sensor switching component is provided at the entrance of the branch flow path, and the main control chip is also connected to the sensor switching component; And / or the flow resistance structure is configured with at least two with different flow resistances, each flow resistance structure is connected in parallel with each other, a flow resistance switching component is provided at the entrance of the branch flow path where each flow resistance structure is located, and the main control chip is also connected to the flow resistance switching component.

[0013] Furthermore, two flow measurement units are provided.

[0014] The present invention also relates to a flow measurement method of an integrated full-range high-precision flow controller, the method comprising: Receive external set flow value; Selecting the flow measurement unit corresponding to the preset interval where the set flow value is located as the flow measurement unit put into use; wherein a single preset interval corresponds to at least one flow measurement unit, and the larger the upper limit of the preset interval, the larger the total range of the corresponding flow measurement unit; Controlling the measuring part switching component to switch the fluid to flow only through the flow measuring part put into use; The actual flow value is calculated based on the signal fed back by the flow measurement unit in use.

[0015] The present invention also relates to a flow control method of an integrated full-range high-precision flow controller, the method comprising: Receive external set flow value; Selecting the flow measurement unit corresponding to the preset interval where the set flow value is located as the flow measurement unit put into use; wherein, a single preset interval corresponds to at least one flow measurement unit, and the larger the upper limit of the preset interval, the larger the total range of the corresponding flow measurement unit; Controlling the measuring part switching component to switch the fluid to flow only through the flow measuring part put into use; Calculate the actual flow value based on the signal fed back by the flow measurement unit in use; The actual flow value is compared with the set flow value, and the opening of the control valve is adjusted.

[0016] After adopting the above technical solution, the present invention adopts at least two flow measurement parts with different ranges, selects the corresponding flow measurement part for use according to the set flow value, and selects the signal of the sensor of the corresponding flow measurement part as the feedback signal, so as to accurately measure the flow, realize high-precision adjustment of the control valve opening, and meet the requirements of high-precision measurement and control of large-flow process gas and small-flow process gas at the same time, so as to achieve high-precision flow control within the full range. In addition, the gas cabinet can reduce one gas path design, reduce the related components required on the gas path, such as diaphragm valve, PT, pressure regulating valve, etc., achieve structural integration and compactness, reduce the gas path design cost, and reduce the gas cabinet space. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the integrated full-range high-precision flow controller of the present invention; Figure 2 It is a structural schematic diagram of a first flow measurement unit of the present invention; Figure 3It is a structural schematic diagram of a second flow measurement unit of the present invention; Figure 4 It is a schematic structural diagram of a third flow measurement unit of the present invention; Figure 5 is a schematic structural diagram of a fourth flow measurement unit of the present invention; Figure 6 is a schematic structural diagram of a fifth flow measurement unit of the present invention; Figure 7 is a schematic structural diagram of a sixth flow measurement unit of the present invention; Figure 8 is a schematic structural diagram of a seventh flow measurement unit of the present invention; Fig. 9 is a schematic structural diagram of an eighth flow measurement unit of the present invention; Fig.10 It is a flow chart of the flow measurement method of the integrated full-range high-precision flow controller of the present invention; Fig.11 It is a flow chart of the flow control method of the integrated full-range high-precision flow controller of the present invention; In the figure, 1, fluid conveying flow path; 2, flow measurement part; 2a, single-range pressure measurement part; 2b, single-range thermal measurement part; 2c, multi-range measurement part; 21, sensor; 21a, pressure sensor; 21b, thermal sensor; 22, flow resistance structure; 23, outlet pressure sensor; 3, measurement part switching component; 4, control valve; 5, main control chip; 6, sensor switching component; 7, flow resistance switching component. DETAILED DESCRIPTION

[0018] In order to make the contents of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments in conjunction with the accompanying drawings.

[0019] like Figure 1-9 As shown, an integrated full-range high-precision flow controller includes: The fluid delivery flow path 1 is provided with at least two flow measurement parts 2 of different ranges and connected in parallel with each other, the flow measurement part 2 comprises a sensor 21 and a flow resistance structure 22 used in conjunction with each other, and a measurement part switching component 3 is provided at the entrance of the branch flow path where each flow measurement part 2 is located; The control valve 4 is installed on the fluid delivery flow path 1 and is connected in series with the measuring part switching component 3; The main control chip 5 is connected to the flow measurement unit 2, the measurement unit switching component 3 and the control valve 4 respectively.

[0020] The control valve 4 may be located in the front section of the measuring part switching assembly 3 , or in the rear section of the parallel structure formed by each flow measuring part 2 .

[0021] like Fig.10 As shown, the flow measurement method of the integrated full-range high-precision flow controller includes: S1, the main control chip 5 receives an external set flow value; S2, the main control chip 5 selects the flow measurement unit 2 corresponding to the preset interval where the set flow value is located as the flow measurement unit 2 put into use; wherein, a single preset interval corresponds to at least one flow measurement unit 2, and the larger the upper limit of the preset interval, the larger the total range of the corresponding flow measurement unit 2; S3, the main control chip 5 controls the measuring part switching component 3 to switch to make the fluid flow only through the flow measuring part 2 in use; S4, the main control chip 5 calculates the actual flow value according to the signal fed back by the flow measurement unit 2 put into use.

[0022] like Fig.11 As shown, the flow control method of the integrated full-range high-precision flow controller, based on the above flow measurement method, also includes: S5, the main control chip 5 compares the actual flow value with the set flow value and adjusts the opening of the control valve 4.

[0023] In some embodiments, Figure 2 As shown, at least a portion of the flow measurement part 2 is a single-range pressure measurement part 2a, and its sensor 21 is a pressure sensor 21a. The pressure sensor 21a and the flow resistance structure 22 used in conjunction with it are installed in series.

[0024] In some embodiments, Figure 2 As shown, the single-range pressure measuring part 2a further includes an outlet pressure sensor 23 , which is installed at the rear of the flow resistance structure 22 of the single-range pressure measuring part 2a and connected to the main control chip 5 .

[0025] Since the outlet of the fluid conveying flow path 1 is generally connected to a vacuum cavity or a reaction chamber, when the equipment is running, the outlet of the fluid conveying flow path 1 is always in a vacuum state under the continuous operation of the vacuum pump. The inlet of the fluid conveying flow path 1 is generally connected to the factory gas source, and is affected by the change in the opening of the control valve 4. The pressure collected by the upstream pressure sensor 21a will also change continuously. It is precisely because the change in pressure has a functional relationship with the flow rate that the embodiment can also set an outlet pressure sensor 23 at the downstream (outlet) of the fluid conveying flow path 1, and calculate the flow value based on the signals of the corresponding upstream pressure sensor 21a and the downstream outlet pressure sensor 23, so as to avoid the calculated flow value being affected by the opening of the control valve 4, thereby ensuring the accuracy of the actual flow value obtained.

[0026] In some embodiments, Figure 3As shown, at least a portion of the flow measurement portion 2 is a single-range thermal measurement portion 2b, and its sensor 21 is a thermal sensor 21b. The thermal sensor 21b and the flow resistance structure 22 used in conjunction with it are installed in parallel.

[0027] In some embodiments, Figures 4 to 9 As shown, at least a portion of the flow measurement unit 2 is a multi-range measurement unit 2c, in which: The sensor 21 is configured with at least two sensors of different ranges. When the sensor 21 is a pressure sensor 21a, each sensor 21 is connected in series in sequence; when the sensor is a thermal sensor 21b, each sensor 21 is connected in parallel with each other, and a sensor switching component 6 is provided at the entrance of the branch path where each sensor 21 is located, and the main control chip 5 is also connected to the sensor switching component 6; And / or the flow resistance structure 22 is configured with at least two flow resistances of different types, each flow resistance structure 22 is connected in parallel, a flow resistance switching component 7 is provided at the entrance of each branch flow path where each flow resistance structure 22 is located, and the main control chip 5 is also connected to the flow resistance switching component 7 .

[0028] It should be noted that the main purpose of the flow resistance structure 22 is to maintain a laminar flow and provide air resistance. The measuring part switching component 3, the sensor switching component 6 and the flow resistance switching component 7 can all be switching valves.

[0029] In the above-mentioned embodiment, two, three, four, etc. flow measurement units 2 may be provided.

[0030] It is preferred to configure two, when the set flow value is relatively small, the preset interval is [0,n%Q fs ], the small-range flow measurement unit 2 is selected for use. When the set flow value is relatively large, the preset interval is (n%Q fs ,Q fs ], there are two ways, the first is to select a large-range flow measurement unit 2 for use, and the second is to select a large-range and a small-range flow measurement unit 2 for use at the same time. n can be 5, 20, 25, etc., and is not limited here.

[0031] Assume that the full scale flow rate of mass flow control is Q fs , then, when the first method is selected, the measurement range of the large-range flow measurement unit 2 is Q1=Q fs , the area where its accuracy can be guaranteed is a%Q fs The above, the measurement range of the small-range flow measurement unit 2 is designed to be Q2 ≥ a%Q fs , and the area where its accuracy can be guaranteed contains a%Q fsWithin, it should cover the minimum controllable value of control valve 4. When the second option is selected, the full scale flow rate of the mass flow controller can actually reach Q1+Q2. This method can broaden the range of the compact full-scale high-precision flow controller.

[0032] The solutions involved in the above embodiments are described in detail below in conjunction with specific embodiments.

[0033] Embodiment 1: Figure 1 , 2 As shown, an integrated full-range high-precision flow controller includes: The fluid delivery flow path 1 is provided with two flow measurement parts 2 of different ranges and connected in parallel with each other, the flow measurement part 2 comprises a sensor 21 and a flow resistance structure 22 used in conjunction with each other, and a measurement part switching component 3 is provided at the entrance of the branch flow path where each flow measurement part 2 is located; The control valve 4 is installed on the fluid delivery path 1 and is located in front of the measuring part switching component 3; The main control chip 5 is connected to the flow measurement unit 2, the measurement unit switching component 3 and the control valve 4 respectively.

[0034] Both flow measurement parts 2 are Figure 2 The single-range pressure measuring section 2a is shown.

[0035] Embodiment 2: Figure 1 , 3 As shown, the main difference between this embodiment and the first embodiment is that both flow measurement parts 2 are Figure 3 The single-range thermal measuring section 2b is shown.

[0036] Embodiment 3: Figure 1 , 4 As shown, the difference between this embodiment and the first embodiment is that both flow measurement parts 2 are Figure 4 The multi-range measuring part 2c shown in the figure, the multi-range measuring part 2c in this embodiment includes two pressure sensors 21a with different ranges. In each multi-range measuring part 2c, two pressure sensors and a flow resistance structure 22 are connected in series in the branch flow path where the multi-range measuring part 2c is located along the fluid flow direction.

[0037] During the control process, the main control chip 5 selects the flow measurement unit 2 corresponding to the preset interval where the set flow value is located as the flow measurement unit 2 put into use, and then selects the effective pressure sensor 21a in the flow measurement unit 2 put into use according to the smaller preset interval where the set flow value is located. The main control chip 5 controls the measurement unit switching component 3 to switch to make the fluid flow only through the flow measurement unit 2 put into use, and then calculates the actual flow value according to the signal fed back by the effective pressure sensor 21a. In this way, the entire mass flow controller can have multiple range selection ranges, realize more precise control, and further improve the accuracy of fluid flow measurement and control, especially the measurement and control accuracy under small flow setting values.

[0038] Embodiment 4: Figure 1 and Figure 5 As shown, the main difference between this embodiment and the first embodiment is that both flow measurement parts 2 are Figure 5 The multi-range measuring part 2c shown in the figure, the multi-range measuring part 2c in this embodiment has two thermal sensors 21b with different ranges, in each multi-range measuring part 2c, the two thermal sensors 21b are connected in parallel, and a sensor switching component 6 is arranged at the parallel entrance, and the structure formed by the two thermal sensors 21b and the sensor switching component 6 is connected in parallel with a flow resistance structure 22.

[0039] During the control process, the main control chip 5 selects the flow measurement unit 2 corresponding to the preset interval where the set flow value is located as the flow measurement unit 2 put into use, and then selects the thermal sensor 21b put into use in the flow measurement unit 2 put into use according to the smaller preset interval where the set flow value is located. The main control chip 5 controls the measurement unit switching component 3 to switch to make the fluid flow only from the flow measurement unit 2 put into use, and controls the sensor switching component 6 to switch to make the fluid flow only from the branch where the thermal sensor 21b put into use is located, and calculates the actual flow value according to the signal fed back by the thermal sensor 21b put into use. In this way, the entire mass flow controller can have multiple range selection ranges, realize more precise control, and further improve the accuracy of fluid flow measurement and control, especially the measurement and control accuracy under small flow setting values.

[0040] Embodiment 5: Figure 1 and Figure 6 As shown, the main difference between this embodiment and the first embodiment is that both flow measurement parts 2 are Figure 6 The multi-range measuring part 2c shown in the figure, the multi-range measuring part 2c in this embodiment includes a pressure sensor 21a and two flow resistance structures 22 with different flow resistances. The two flow resistance structures 22 are connected in parallel, and a flow resistance switching component 7 is arranged at the parallel inlet. The pressure sensor 21a and the structure formed by the flow resistance switching component 7 and the two flow resistance structures 22 are connected in series in sequence along the fluid flow direction.

[0041] During the control process, the main control chip 5 selects the flow measurement unit 2 corresponding to the preset interval where the set flow value is located as the flow measurement unit 2 put into use, and then selects the flow resistance structure 22 put into use in the flow measurement unit 2 put into use according to the smaller preset interval where the set flow value is located. The main control chip 5 controls the measurement unit switching component 3 to switch to make the fluid flow only from the flow measurement unit 2 put into use, and controls the flow resistance switching component 7 to switch to make the fluid flow only from the branch path where the flow resistance structure 22 put into use is located, and calculates the actual flow value according to the signal fed back by the pressure sensor 21a of the flow measurement unit 2 put into use. In this way, the entire mass flow controller can have multiple range selection ranges, realize more precise control, and further improve the accuracy of fluid flow measurement and control, especially the measurement and control accuracy under small flow setting values.

[0042] Example 6: Figure 1 and Figure 7 As shown, the main difference between this embodiment and the first embodiment is that both flow measurement parts 2 are Figure 7 The multi-range measuring part 2c shown in the figure, the multi-range measuring part 2c in this embodiment includes a thermal sensor 21b and two flow resistance structures 22 with different flow resistances. The two flow resistance structures 22 are connected in parallel, and a flow resistance switching component 7 is arranged at the parallel inlet. The thermal sensor 21b and the structure formed by the flow resistance switching component 7 and the two flow resistance structures 22 are connected in parallel.

[0043] During the control process, the main control chip 5 selects the flow measurement unit 2 corresponding to the preset interval where the set flow value is located as the flow measurement unit 2 put into use, and then selects the flow resistance structure 22 put into use in the flow measurement unit 2 put into use according to the smaller preset interval where the set flow value is located. The main control chip 5 controls the measurement unit switching component 3 to switch to make the fluid flow only from the flow measurement unit 2 put into use, and controls the flow resistance switching component 7 to switch to make the fluid flow only from the branch path where the flow resistance structure 22 put into use is located, and calculates the actual flow value according to the signal fed back by the thermal sensor 21b of the flow measurement unit 2 put into use. In this way, the entire mass flow controller can have multiple range selection ranges, realize more precise control, and further improve the accuracy of fluid flow measurement and control, especially the measurement and control accuracy under small flow setting values.

[0044] Embodiment 7: Figure 1 and Figure 8 As shown, the main difference between this embodiment and the first embodiment is that both flow measurement parts 2 are Figure 8The multi-range measuring part 2c shown in the figure, the multi-range measuring part 2c in this embodiment includes two pressure sensors 21a with different ranges and two flow resistance structures 22 with different flow resistances. The two flow resistance structures 22 are connected in parallel, and a flow resistance switching component 7 is arranged at the parallel inlet. The two pressure sensors 21a and the structure formed by the flow resistance switching component 7 and the two flow resistance structures 22 are connected in series in sequence along the fluid flow direction.

[0045] During the control process, the main control chip 5 selects the flow measurement part 2 corresponding to the preset interval where the set flow value is located as the flow measurement part 2 put into use, and then selects the flow resistance structure 22 and the effective pressure sensor 21a put into use in the flow measurement part 2 put into use according to the smaller preset interval where the set flow value is located. The main control chip 5 controls the measurement part switching component 3 to switch to make the fluid flow only from the flow measurement part 2 put into use, and controls the flow resistance switching component 7 to switch to make the fluid flow only from the branch path where the flow resistance structure 22 put into use is located, and calculates the actual flow value according to the signal fed back by the effective pressure sensor 21a. In this way, the entire mass flow controller can have more range selection ranges, realize more precise control, and better improve the accuracy of fluid flow measurement and control, especially the measurement and control accuracy under small flow setting values.

[0046] Embodiment 8: Figure 1 and Fig. 9 As shown, the main difference between this embodiment and the first embodiment is that both flow measurement parts 2 are Fig. 9 The multi-range measuring part 2c shown in the figure, the multi-range measuring part 2c in this embodiment includes two thermal sensors 21b with different ranges and two flow resistance structures 22 with different flow resistances, the two thermal sensors 21b are connected in parallel, and a sensor switching component 6 is set at the parallel entrance, the two flow resistance structures 22 are connected in parallel, and a flow resistance switching component 7 is set at the parallel entrance, and the structure composed of the two thermal sensors 21b and the sensor switching component 6 and the structure formed by the flow resistance switching component 7 and the two flow resistance structures 22 are connected in parallel.

[0047] During the control process, the main control chip 5 selects the flow measurement part 2 corresponding to the preset interval where the set flow value is located as the flow measurement part 2 put into use, and then selects the flow resistance structure 22 put into use and the thermal sensor 21b put into use in the flow measurement part 2 put into use according to the smaller preset interval where the set flow value is located. The main control chip 5 controls the measurement part switching component 3 to switch to make the fluid flow only from the flow measurement part 2 put into use, and controls the flow resistance switching component 7 to switch to make the fluid flow only from the branch where the flow resistance structure 22 put into use is located, and controls the sensor switching component 6 to switch to make the fluid flow only from the branch where the thermal sensor 21b put into use is located, and calculates the actual flow value according to the signal fed back by the thermal sensor 21b put into use. In this way, the entire mass flow controller can have more range selection ranges, realize more precise control, and better improve the accuracy of fluid flow measurement and control, especially the measurement and control accuracy under small flow setting values.

[0048] Embodiment 9: The main difference between this embodiment and embodiment 1 is that the structures of the two flow measurement parts 2 are different. Figures 2 to 9 Any two structures in .

[0049] It should be noted that in the fifth to eighth embodiments, when the set flow value of the mass flow controller is relatively large, one flow resistance structure 22 can be selected for use, or two flow resistance structures 22 can be selected for use at the same time. When the latter is selected, the range of the mass flow controller can be widened.

[0050] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. An integrated full-range high-precision flow controller, characterized in that: include: A fluid delivery flow path (1) is provided with at least two flow measurement parts (2) of different measuring ranges and connected in parallel with each other, the flow measurement parts (2) comprising a sensor (21) and a flow resistance structure (22) used in conjunction with each other, and a measurement part switching assembly (3) is provided at the entrance of the branch flow path where each flow measurement part (2) is located; A control valve (4) is installed on the fluid delivery path (1) and is connected in series with the measuring part switching assembly (3); A main control chip (5) is respectively connected to the flow measurement unit (2), the measurement unit switching component (3) and the control valve (4).

2. The integrated full-range high-precision flow controller according to claim 1, characterized in that: At least a portion of the flow measurement part (2) is a single-range pressure measurement part (2a), and its sensor (21) is a pressure sensor (21a). The pressure sensor (21a) and the flow resistance structure (22) used in conjunction with the pressure sensor (21a) are installed in series.

3. The integrated full-range high-precision flow controller according to claim 2, characterized in that: The single-range pressure measuring part (2a) further comprises an outlet pressure sensor (23), wherein the outlet pressure sensor (23) is installed at the rear of the flow resistance structure (22) of the single-range pressure measuring part (2a) where the outlet pressure sensor (23) is located, and is connected to the main control chip (5).

4. The integrated full-range high-precision flow controller according to claim 1, characterized in that: At least a portion of the flow measurement portion (2) is a single-range thermal measurement portion (2b), and its sensor (21) is a thermal sensor (21b). The thermal sensor (21b) and a flow resistance structure (22) used in conjunction with the thermal sensor (21b) are installed in parallel.

5. The integrated full-range high-precision flow controller according to claim 1, characterized in that: At least a portion of the flow measurement unit (2) is a multi-range measurement unit (2c), in which: The sensor (21) is configured with at least two sensors of different measuring ranges. When the sensor (21) is a pressure sensor (21a), the sensors (21) are sequentially connected in series. When the sensor is a thermal sensor (21b), the sensors (21) are connected in parallel with each other. A sensor switching component (6) is provided at the entrance of the branch flow path, and the main control chip (5) is also connected to the sensor switching component (6). And / or the flow resistance structure (22) is configured with at least two flow resistances of different types, the flow resistance structures (22) are connected in parallel with each other, a flow resistance switching component (7) is provided at the entrance of the branch flow path where each flow resistance structure (22) is located, and the main control chip (5) is also connected to the flow resistance switching component (7).

6. The integrated full-range high-precision flow controller according to any one of claims 1 to 5, characterized in that: The flow measurement units (2) are provided in two numbers.

7. A flow measurement method of an integrated full-range high-precision flow controller according to any one of claims 1 to 6, characterized in that: Methods include: Receive external set flow value; Selecting a flow measurement unit (2) corresponding to a preset interval in which the set flow value is located as the flow measurement unit (2) put into use; wherein a single preset interval corresponds to at least one flow measurement unit (2), and the larger the upper limit of the preset interval, the larger the total range of the corresponding flow measurement unit (2); Controlling the measuring section switching component (3) to switch the fluid to flow only through the flow measuring section (2) in use; The actual flow value is calculated based on the signal fed back from the flow measurement unit (2) put into use.

8. A flow control method based on the flow measurement method of the integrated full-range high-precision flow controller according to claim 7, characterized in that: Methods include: Get the actual flow value; Compare the actual flow value with the set flow value and adjust the opening of the control valve (4).

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