Mass flow control having advanced zero-directed diagnosis

Abstract

To provide a diagnosing system for calibrating a mass flow control having a controller coupled for communication to a sensor and a valve, which controller is to control the valve based on a predetermined set-point value and communication information from at least one sensor.SOLUTION: A mass flow control includes a controller that determines the number of set-point value adjustments and compares a result of calibrating operation with set-point and allowable error values. The controller generates a notification message indicative of at least one of a predetermined number of set-point value adjustments and a result of comparison. The controller calibrates the mass flow control based at least partially on the predetermined number of set-point value adjustments, the result of comparison and a user input. The notification message may include a temperature value, a valve drive value, a sensor flow-rate value, gas flow hours, and a remaining number of total fluid hours-based set-point adjustments.SELECTED DRAWING: Figure 1

Description

[Background technology]

[0001] Many industrial processes require precise control of various process fluids. For example, in the semiconductor industry, mass flow meters (MFMs) are used to precisely measure the amount of process fluid introduced into a process chamber. In addition to measuring the mass flow rate, mass flow controllers (MFCs) are used to precisely measure and control the amount of process fluid introduced into a process chamber. It should be understood that the term fluid as used herein applies to any type of gas or vapor where control of the flow rate may be important.

[0002] Maintenance of these devices is required to maintain acceptable performance levels. Maintenance of these devices is timely and can require advanced knowledge of device operation, and therefore can be expensive to maintain. Many MFCs have self-diagnostic capabilities based on built-in hardware with limited capabilities. The limited capabilities and complex designs of existing MFC diagnostic systems only increase the cost of the MFC.

[0003] Exemplary embodiments of the presently disclosed subject matter are described in detail below with reference to the accompanying drawings, which are incorporated herein by reference. [Brief description of the drawings]

[0004] [Figure 1] FIG. 1 illustrates a mass flow controller with control and advanced diagnostic electronics in accordance with certain example embodiments. [Figure 2A] FIG. 1 is a diagram of an algorithm for diagnosing and controlling the operation of a mass flow controller, in accordance with certain example embodiments. [Figure 2B] FIG. 1 is a diagram of an algorithm for diagnosing and controlling the operation of a mass flow controller, in accordance with certain example embodiments. [Diagram 3]FIG. 2 is a block diagram illustrating a computing machine and system applications in accordance with certain example embodiments. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0005] Although the making and use of various embodiments of the present disclosure are discussed in detail below, it should be understood that the present disclosure provides many applicable inventive concepts that can be embodied in a wide variety of specific contexts. The specific embodiments discussed herein are merely exemplary and do not define the scope of the present disclosure. For purposes of clarity, the present disclosure may not describe all features of an actual implementation. Of course, in developing any such actual embodiment, many implementation-specific judgments must be made to achieve the developer's specific goals, including compliance with system-related and business-related constraints that vary from implementation to implementation. Moreover, it will be appreciated that such a development effort may be complex and time-consuming, but would be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.

[0006] MFCs tuned to control a particular type of fluid under known conditions, i.e., pressure, volume, and temperature, can often become detuned during installation, maintenance, and testing. Additionally, MFCs can become detuned due to unknown operating conditions or simply due to use, i.e., wear and tear. All things considered, detuning of MFCs can be determined by understanding normal and abnormal MFC variable behavior and acting on recognized problems before they affect related operations, e.g., yield in a manufacturing supply chain. Thus, advanced MFC diagnostic systems can improve the operation of a manufacturing supply chain. However, without careful consideration, designing and developing a system to address such issues can be complex and very expensive.

[0007] Disclosed herein is an advanced diagnostic system that is used to calibrate and control the operation of a previously tuned MFC. The diagnostic system monitors select variables, such as adjustments and backflow rate against setpoint values, and if a problem is recognized, generates a notification and causes the MFC to calibrate and shut down. The diagnostic system can retune the MFC based on the revised adjustment variable or variables, such as setpoint, temperature, pressure, and volume. Additionally, if the backflow rate reaches an undesirable level, the diagnostic system can shut down the MFC. Additionally, the advanced diagnostic system can be designed and developed entirely in software, such as firmware, or in a combination of hardware and software.

[0008] As used herein, tune refers to an MFC that has been previously adjusted, for example, in a laboratory or MFC manufacturing facility, before a repair is initiated. Calibration, as used herein, refers to an operation performed on an MFC controller that adjusts a control variable to reflect any changes from when the MFC is tuned to when it is operating or during its operation. A setpoint is a variable that includes an identifier and a value. The setpoint is the desired flow rate and is set during the tuning stage based on known factors such as fluid type, pressure, volume, and temperature. During MFC operation, there may be many adjustments to the setpoint, for example, to correct for slight drifts caused by normal operation of the MFC. As discussed later, the number of adjustments may reflect some issues with the MFC, or more specifically, with the tuning variables of the MFC. As used herein, backflow refers to the flow rate of a fluid back to a fluid source. As an example, fluids used in manufacturing processes, such as the manufacture of semiconductor devices, travel from an upstream source to a downstream process chamber. In this example, the backflow refers to a fluid traveling back to an upstream source.

[0009] 1 shows an example of a thermal mass flow controller (MFC) 100 according to an embodiment of the disclosure, but other types of mass flow sensing methods can be included. The mass flow controller 100 includes a block 110, which is a platform on which the components of the MFC 100 are mounted. A thermal mass flow meter 140 and a valve assembly 150 including a control valve 170 are mounted on the block 110 between a fluid inlet 120 and a fluid outlet 130. The thermal mass flow meter 140 typically includes a bypass 142 through which a majority of the fluid flows and a thermal flow sensor 146 through which a smaller portion of the fluid flows. The bypass 142 is calibrated with known fluids to determine the appropriate relationship between the fluid flowing through the mass flow sensor and the fluid flowing through the bypass 142 at various known flow rates, so that the total flow rate through the flow meter can be determined from the thermal flow sensor output signal. The thermal flow sensor 146 and bypass 142 can then be connected to the control valve 170 and the control and diagnostics and controller 160, and then calibrated again under known conditions. The response of control and diagnostics and controller 160 and control valve 170 is then characterized so that the overall response of the system to a change in set point or input pressure is known and can be used to control the system to provide the desired response. Other functions of control and diagnostics and controller 160 include advanced diagnostic features related to zero trending, zero recommended, bad zero determination, excessive zero drift, and back streaming, as discussed in more detail with respect to Figures 2 and 3.

[0010] The thermal flow sensor 146 is contained within a sensor housing 102 (portions shown removed to show the thermal flow sensor 146) which is attached to a mounting plate 108. The thermal flow sensor 146 is a small diameter tube, commonly referred to as a capillary tube, and includes a sensor inlet portion 146A, a sensor outlet portion 146B, and a sensor measuring portion 146C around which two resistive coils or windings 147, 148 are disposed. In operation, a current is applied to the two resistive windings 147, 148 which are in thermal contact with the sensor measuring portion 146C. The current in the resistive windings 147, 148 heats the fluid flowing through the measuring portion 146C to a temperature higher than the temperature of the fluid flowing through the bypass 142. The resistance of the windings 147, 148 changes with temperature. As fluid flows through the sensor conduit, heat is transferred from the upstream resistor 147 to the downstream resistor 148, and the temperature difference is proportional to the mass flow rate through the sensor.

[0011] An electrical signal is derived from the two resistive windings 147, 148 that is related to the flow rate through the sensor. The electrical signal can be derived in a number of different ways, such as from the difference in the resistance of the resistive windings or from the difference in the amount of energy provided to each resistive winding to maintain each winding at a particular temperature. Examples of the various ways in which an electrical signal that correlates to the flow rate of fluid in a thermal mass flow meter can be determined are described, for example, in commonly owned U.S. Patent No. 6,845,659, which is incorporated herein by reference. The electrical signal derived from the resistive windings 147, 148 after signal processing comprises the sensor output signal.

[0012] The sensor output signal can be correlated with the mass flow rate at the mass flow meter to determine the fluid flow rate when the electrical signal is measured. The sensor output signal is typically correlated first with the flow rate at the sensor 146 and then with the mass flow rate at the bypass 142 to determine the total flow rate through the flow meter and control valve 170 can be controlled accordingly. The correlation between the sensor output signal and the fluid flow rate is complex and depends on many operating conditions including fluid type, flow rate, inlet and / or outlet pressure, temperature, etc.

[0013] The process of correlating the raw sensor output to the fluid flow rate requires tuning and / or calibration of the mass flow controller. For example, a mass flow sensor can be tuned by flowing a known amount of a known fluid through the sensor portion and adjusting certain signal processing parameters to provide a response that accurately represents the fluid flow rate. For example, the output can be normalized so that a specified voltage range, such as 0V-5V, of the sensor output corresponds to a flow rate range from zero to the top of the range for the sensor. The output can also be linearized so that changes in the sensor output correspond linearly to changes in flow rate. For example, if the output is linearized, doubling the fluid output doubles the electrical output. The dynamic response of the sensor, i.e., the inaccurate effects of pressure or flow rate changes that occur when flow rate or pressure changes are determined, can be determined and compensated for. Diagnostics of the sensor can also be performed to determine whether the sensor requires maintenance or whether other aspects of the MFC require attention or maintenance.

[0014] Mass flow controller operation is generally degraded when the type of fluid used by the end user is different from the type of fluid used in the adjustment and / or calibration, or when the operating conditions, such as inlet and outlet pressures, temperatures, flow rate ranges, etc., used by the end user are different from those used in the adjustment and / or calibration. For this reason, flow meters can be adjusted or calibrated using additional fluids (called "substitute fluids") and / or operating conditions, and any changes necessary to provide sufficient response are stored in a look-up table. U.S. Patent No. 7,272,512 to Wang et al., entitled "Flow Sensor Signal Conversion," owned by the assignee of the present invention and incorporated herein by reference, describes a system that uses the properties of different gases to adjust the response, rather than requiring substitute fluids to calibrate the device for each different process fluid used.

[0015] Additionally, the mass flow controller 100 may include a pressure transducer 112 coupled to the flow path to measure the pressure within the flow path, typically, but not limited to, somewhere upstream of the bypass 142. The pressure transducer 112 provides a pressure signal indicative of the pressure. According to disclosed embodiments, the pressure transducer 112 is used to measure the pressure during flow measurement.

[0016] The diagnostic and controller 160 controls the position of the control valve 170 according to a setpoint indicative of a desired mass flow rate and an electrical flow signal from the mass flow sensor indicative of the actual mass flow rate of the fluid flowing through the sensor conduit. Conventional feedback control methods, such as proportional control, integral control, proportional-integral (PI) control, derivative control, proportional-derivative (PD) control, integral-derivative (ID) control, and proportional-integral-derivative (PID) control, are then used to control the flow rate of the fluid in the mass flow controller. A control signal (e.g., a control valve drive signal) is generated based on an error signal that is the difference between a setpoint signal indicative of the desired mass flow rate of the fluid and a feedback signal related to the actual mass flow rate sensed by the mass flow sensor. The control valve is disposed in the primary fluid flow path (usually downstream of the bypass and the mass flow sensor) and can be controlled (e.g., opened or closed) to vary the mass flow rate of the fluid flowing through the primary fluid flow path, and this control is provided by the mass flow controller 100.

[0017] In the illustrated example, the flow rate is provided as a voltage signal by conductors 158 to a closed loop system and diagnostics and controller 160. The signal is amplified, processed and provided to a control valve assembly 150 using conductors 159 to modify the flow rate. To this end, the controller 160 compares the signal from the mass flow sensor 140 to a predetermined value and adjusts a control valve 170 accordingly to achieve the desired flow rate. The control valve 170 may be a piezoelectric or other technology valve configured to operate at flow rates of 2 standard liters per minute or greater.

[0018] 2A and 2B, diagrams of algorithms for diagnostic and control operation of MFC 100 are shown, according to an example embodiment. FIG. 2A is a diagram of an algorithm for locally diagnosing and controlling operation of MFC 100. At block 200, selected variables, i.e., MFC process and control variables, are monitored. Process variables can include measured pressure, temperature, volume, and fluid flow rate. Control variables can include known variables, such as setpoint, setpoint adjustment, temperature volume, fluid type, flow rate, and predetermined variables. Setpoint variable is the measured flow rate. Predetermined variables can be the number of desired setpoints, setpoint adjustment, backflow, and backflow rate. The desired setpoint and desired flow rate are based on known fluid type, pressure, temperature, direction, and volume. Setpoint adjustment is the number of adjustments made by controller 160. At block 202, the number of setpoint adjustments is determined. During the normal course of MFC 100 operation, the fluid flow rate may deviate from the desired setpoint. At block 204, the number of setpoint adjustments is compared to at least one predetermined number. The comparison can be between the total number of adjustments as a function of total gas hours, e.g., 128 adjustments as a function of total gas. This information is useful to understand the structure and stability of the MFC 100 before performing an as-found calibration check. A zero adjustment or 128 adjustments can indicate, for example, a potential problem. A zero adjustment can indicate that system protocols are not being followed, that the MFC 100 is installed incorrectly, contaminant build-up, or drifting of the MFC 100, which could possibly mean a non-functioning MFC. An adjustment of 128 can indicate, for example, degradation of MFC 100 components and / or deviations in operating conditions, any of which constitute a diagnostic or health check and possibly a calibration. At block 206, a notification message is generated.The notification message may include at least one of the following: at least one value for temperature, valve drive, set point, sensor flow rate, gas flow hours, time, fluid type, and at least one of the remaining number of set point adjustments based on total fluid hours. At block 208, the variables or selected variables are calibrated based on the particular situation. Calibration may only require resetting the desired set point. However, calibration may require partial or complete readjustment of the MFC 100 based on partially or completely different known variable settings. Calibration is performed at least in part based on one of a predetermined number of set point value adjustments, the results of the comparison, and user input. Other variables may also be monitored. At block 210, the backflow rate may be monitored. If the backflow rate exceeds a predetermined value, for example, a percentage of the total flow rate or a percentage of the total flow rate over a period of time, the operation of the MFC 100 is controlled (block 212). In this case, the algorithm may force the MFC 100 into a hard fault or safe state. At block 214, the event is logged. The logged information may include date, time, and device identifier. Although blocks 208 and 214 are described as being performed locally in this embodiment, it should be understood that the calibration commands may be performed remotely and the logging system may be designed to store the logging data remotely. Referring now to FIG. 2B, a diagram of an algorithm for processing diagnostic or logging data and controlling the diagnostic and controller 160 from a centralized controller, such as a Programmable Logic Controller (PLC) or Distributed Control System (DCS), is shown. At block 216, the centralized controller receives notification messages and / or logging data from multiple MFCs 100. A process engineer may act according to this information.At block 218, the MFC 100 and the diagnostics and controller 160 may be calibrated or their operation may be controlled.

[0019] As used herein, the term hard fault means that the MFC 100 is not operational due to, for example, liquid in a sensor that may affect the MFC's ability to detect changes in temperature. Safe states are software or hardware settings that force the MFC 100 into a predetermined valve state. Safe states are used during start-up and recovery for process and tool alarms.

[0020] Referring now to FIG. 3, a computing machine 300 and a system application module 400 are shown according to an exemplary embodiment. The computing machine 300 can correspond to any of a variety of computers, mobile devices, laptop computers, servers, embedded systems, or computing systems presented herein. The module 400 can include one or more hardware or software elements, such as other OS applications and user and kernel space applications, designed to facilitate the computing machine 300 to execute the various methods and processing functions presented herein. The computing machine 300 can include various internal or attached components, such as a processor 310, a system bus 320, a system memory 330, a storage medium 340, an input / output interface 350, a network interface 360 ​​for communicating with a network 370, such as a local loop, cellular / GPS, Bluetooth, or WiFi, and a set of sensors 380, such as any of the sensors identified in connection with FIG. 1.

[0021] The computing machine may be implemented as a conventional computer system, an embedded controller, a laptop, a server, a mobile device, a smart phone, a wearable computer, a customized machine, any other hardware platform, or any combination or plurality of them. The computing machine may be a distributed system configured to function using multiple computing machines interconnected via a data network or bus system.

[0022] The processor 310 can be designed to execute code instructions to perform the operations and functions described herein, manage request flow and address mapping, perform calculations and generate commands. The processor 310 can be configured to monitor and control the operation of components in the computing machine. The processor 310 can be a general-purpose processor, a processor core, a multiprocessor, a reconfigurable processor, a microcontroller, a digital signal processor ("DSP"), an application specific integrated circuit ("ASIC"), a controller, a state machine, gate logic, a discrete hardware component, any other processing unit, or any combination or plurality thereof. The processor 310 can be a single processing unit, multiple processing units, a single processing core, multiple processing cores, a dedicated processing core, a coprocessor, or any combination thereof. According to certain embodiments, the processor 310 can be a software-based or hardware-based virtual computing machine executing within one or more other computing machines, along with other components of the computing machine 300.

[0023] The system memory 330 may include non-volatile memory, such as read-only memory ("ROM"), programmable read-only memory ("PROM"), erasable programmable read-only memory ("EPROM"), flash memory, or any other device capable of storing program instructions or data with or without the application of power. The system memory 330 may also include volatile memory, such as random access memory ("RAM"), static random access memory ("SRAM"), dynamic random access memory ("DRAM"), and synchronous dynamic random access memory ("SDRAM"). Other types of RAM may also be used to implement the system memory 330. The system memory 330 may be implemented using a single memory module or multiple memory modules. Although the system memory 330 is shown as being part of the computing machine, those skilled in the art will understand that the system memory 330 may be separate from the computing machine 300 without departing from the scope of the subject technology. It should also be understood that the system memory 330 may include or operate in conjunction with a non-volatile storage device, such as the storage medium 340.

[0024] The storage medium 340 may include a hard disk, a floppy disk, a compact disk read-only memory ("CD-ROM"), a digital versatile disk ("DVD"), a Blu-ray disk, a magnetic tape, a flash memory, other non-volatile memory devices, a solid-state drive ("SSD"), any magnetic storage device, any optical storage device, any electrical storage device, any semiconductor storage device, any physically based storage device, any other data storage device, or any combination or plurality of such. The storage medium 340 may store one or more operating systems, application programs and program modules, data, or any other information. The storage medium 340 may be part of a computing machine or may be connected to a computing machine. The storage medium 340 may also be part of one or more other computing machines in communication with the computing machine, such as a server, a database server, cloud storage, network attached storage, etc.

[0025] The application module 400 and other OS application modules may include one or more hardware or software elements configured to facilitate a computing machine to execute various methods and processing functions presented herein. The application module 400 and other OS application modules may include one or more algorithms or sequences of instructions stored as software or firmware in association with the system memory 330, the storage medium 340, or both. The storage medium 340 may thus represent an example of a machine or computer readable medium that may store instructions or code for execution by the processor 310. A machine or computer readable medium may generally refer to any medium or media used to provide instructions to the processor 310. Such machine or computer readable media associated with the application module 400 and other OS application modules may include computer software products. It should be understood that the computer software products including the application module 400 and other OS application modules may also be associated with one or more processes or methods of distributing the application module 400 and other OS application modules to a computing machine via a network, any signal-carrying medium, or any other communication or distribution technology. Application module 400 and other OS application modules may also include hardware circuitry or information for configuring hardware circuitry, such as microcode, or configuration information for an FPGA or other PLD. In one example embodiment, application module 400 and other OS application modules may include algorithms capable of performing the functional operations described by the flowcharts and computer systems presented herein.

[0026] The input / output ("I / O") interface 350 can be configured to couple to one or more external devices, receive data from one or more external devices, and transmit data to one or more external devices. Such external devices, along with various internal devices, may also be known as peripheral devices. The I / O interface 350 can include both electrical and physical connections to couple various peripheral devices to the computing machine or processor 310. The I / O interface 350 can be configured to communicate data, address, and control signals between the peripheral devices and the computing machine or processor 310. The I / O interface 350 can be configured to implement any standard interface, such as Small Computer System Interface ("SCSI"), Serial Attached SCSI ("SAS"), Fibre Channel, Peripheral Component Interconnect ("PCI"), PCI Express (PCIe), serial bus, parallel bus, Advanced Technology Attachment ("ATA"), Serial ATA ("SATA"), Universal Serial Bus ("USB"), Thunderbolt, FireWire, various video buses, etc. I / O interface 350 may be configured to implement only one interface or bus technology. Alternatively, I / O interface 350 may be configured to implement multiple interface or bus technologies. I / O interface 350 may be configured to operate as part of, as all of, or in conjunction with system bus 320. I / O interface 350 may include one or more buffers for buffering transmissions between one or more external devices, internal devices, computing machines, or processors 310.

[0027] I / O interface 350 can couple the computing machine to a variety of input devices including a mouse, touch screen, scanner, electronic digitizer, sensor, receiver, touch pad, track ball, camera, microphone, keyboard, any other pointing device, or any combination thereof. I / O interface 350 can couple the computing machine to a variety of output devices including video displays, speakers, printers, projectors, haptic feedback devices, automation controls, robotic components, actuators, motors, fans, solenoids, valves, pumps, transmitters, signal emitters, lights, etc.

[0028] The computing machine 300 may operate in a networked environment, with logical connections through the NIC 360 to one or more other systems or computing machines over a network. The network may include a wide area network (WAN), a local area network (LAN), an intranet, the Internet, a wireless access network, a wired network, a mobile network, a telephone network, an optical network, or a combination thereof. The network may be a packet-switched network, a circuit-switched network of any topology and may use any communication protocol. The communication links in the network may involve a variety of digital or analog communication media, such as fiber optic cables, free-space optics, wave guides, conductors, wireless links, antennas, radio frequency communications, and the like.

[0029] The processor 310 may be connected to other elements of the computing machine or the various peripherals discussed herein via a system bus 320. It should be understood that the system bus 320 may be internal to the processor 310, external to the processor 310, or both. According to some embodiments, the processor 310, other elements of the computing machine, or any of the various peripherals discussed herein may be incorporated into a single device, such as a system on a chip ("SOC"), system on a package ("SOP"), or ASIC device.

[0030] The embodiments may include a computer program that embodies the functions described and illustrated herein, the computer program being implemented in a computer system that includes instructions stored in a machine-readable medium and a processor that executes the instructions. However, it should be apparent that there may be many different ways to implement the embodiments in computer programming, and the embodiments should not be construed as being limited to any one set of computer program instructions unless otherwise disclosed in the exemplary embodiments. Furthermore, a skilled programmer would be able to write such a computer program to implement one of the disclosed embodiments based on the accompanying flowcharts, algorithms, and related descriptions in the body of the application. Thus, disclosure of a particular set of program code instructions is not deemed necessary to fully understand how to make and use the embodiments. Furthermore, one skilled in the art would understand that one or more aspects of the embodiments described herein may be performed by hardware, software, or a combination thereof, such that they may be embodied in one or more computing systems. Furthermore, any reference to a computer-executed act should not be construed as being performed by a single computer, since two or more computers may perform the act.

[0031] The exemplary embodiments described herein can be used with computer hardware and software to perform the methods and processing functions described above. The systems, methods and procedures described herein can be embodied in a programmable computer, computer executable software, or digital circuitry. The software can be stored on a computer readable medium. For example, computer readable media can include floppy disks, RAM, ROM, hard disks, removable media, flash memory, memory sticks, optical media, magneto-optical media, CD-ROMs, and the like. Digital circuitry can include integrated circuits, gate arrays, building block logic, field programmable gate arrays (FPGAs), and the like.

[0032] The example systems, methods, and acts described in the embodiments presented above are exemplary, and in alternative embodiments, certain acts may be performed in different orders, in parallel with one another, omitted entirely, and / or combined between different example embodiments, and / or certain additional acts may be performed, without departing from the scope and spirit of the various embodiments. Accordingly, such alternative embodiments are included in the description herein.

[0033] As used herein, the singular forms "a", "an" and "the" are intended to include the plural, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising" as used herein specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. As used herein, phrases such as "between X and Y" and "between about X and Y" should be interpreted to include X and Y. As used herein, phrases such as "between about X and Y" mean "between about X and about Y." As used herein, phrases such as "from about X to Y" mean "from about X to about Y."

[0034] As used herein, "hardware" may include a combination of discrete components, an integrated circuit, an application specific integrated circuit, a field programmable gate array, or other suitable hardware. As used herein, "software" may include one or more objects, agents, threads, lines of code, subroutines, separate software applications, two or more lines of code or other suitable software structures operating in one or more processors (wherein the processor may include one or more microcomputers or other suitable data processing units, memory devices, input / output devices, displays, data input devices such as keyboards or mice, peripherals such as printers and speakers, associated drivers, control cards, power supplies, network devices, docking station devices, or other suitable devices operating under the control of a software system with a processor or other devices), two or more software applications, or other suitable software structures. In one exemplary embodiment, the software may include one or more lines of code or other suitable software structures operating in a general-purpose software application, such as an operating system, and one or more lines of code or other suitable software structures operating in a dedicated software application. As used herein, "couple" and cognate terms such as "couples" and "coupled" may include a physical connection (such as through copper conductors), a virtual connection (such as through randomly assigned memory locations in a data memory device), a logical connection (such as through logic gates in a semiconductor device), any other suitable connection, or a suitable combination of such connections.The term "data" may refer to any suitable structure for using, transporting, or storing data, such as a data field, a data buffer, a data message having a data value and sender / recipient address data, a control message having a data value and one or more operators that cause a receiving system or component to perform some function with the data, or other suitable hardware or software component for the electronic processing of data.

[0035] Generally, a software system is a system that runs on a processor to perform a given function in response to a given data field. For example, a system can be defined by the function that the system performs and the data field on which the system performs the function. As used herein, a NAME system (where NAME is typically the name of the generic function performed by the system) refers to a software system that runs on a processor and is configured to perform a disclosed function on a disclosed data field. Unless a specific algorithm is disclosed, any suitable algorithm known to one of ordinary skill in the art to perform a function with the associated data field is contemplated as being within the scope of this disclosure. For example, a message system that generates a message including a sender address field, a recipient address field, and a message field includes software operating on a processor that can obtain the sender address field, the recipient address field, and the message field from a suitable system or device of the processor, such as a buffer device or system, assemble the sender address field, the recipient address field, and the message field into a suitable electronic message format (such as an email message, a TCP / IP message, or any other suitable message format having sender address fields, recipient address fields, and message fields), and transmit the electronic message using the electronic messaging system and device of the processor over a communication medium, such as a network. One of ordinary skill in the art will be able to provide specific encoding for a particular application based on the above disclosure, which is intended to illustrate exemplary embodiments of the present disclosure, but is not intended to provide guidance to persons other than those skilled in the art, such as persons unfamiliar with programming in a suitable programming language or with processors.Specific algorithms for performing certain functions may be provided in flowchart form or other suitable format, and data fields and associated functions may be shown in an exemplary sequence of operations, which sequence may be rearranged as suitable and is not intended as limiting unless expressly stated to be limiting.

[0036] The above disclosed embodiments are presented for the purpose of illustration and to enable those skilled in the art to practice the present disclosure, but the present disclosure is not intended to be exhaustive or limited to the disclosed forms. Many insubstantial modifications and variations will be apparent to those skilled in the art without departing from the spirit and scope of the present disclosure. The claims are intended to broadly encompass the disclosed embodiments and any such modifications. Furthermore, the following clauses represent further embodiments of the present disclosure and should be considered to be within the scope of the present disclosure.

[0037] Clause 1. A mass flow controller comprising an inlet configured to receive a fluid, a flow path through which the fluid passes through the mass flow controller, a valve configured to regulate a flow rate of the fluid out of an outlet of the mass flow controller, at least one sensor configured to monitor the fluid passing through the flow path and valve operation, and a controller communicatively coupled to the at least one sensor and the valve, the controller adapted to control the valve based on a predetermined setpoint value and communication information from the at least one sensor, the controller further comprising a diagnostic system for calibrating the controller, the diagnostic system configured to determine a number of setpoint value adjustments and generate a notification message indicating the predetermined number of setpoint value adjustments. Clause 2. The mass flow controller of clause 1, wherein the predetermined number of setpoint value adjustments is a function of total flow time. Clause 3. The mass flow controller of clause 1, wherein the predetermined number of setpoint value adjustments is 128. Clause 4. The mass flow controller of clause 1, wherein the predetermined number of setpoint value adjustments is zero. Clause 5. The mass flow controller of clause 1, wherein the predetermined number of setpoint adjustments is at least one of a minimum threshold and a maximum threshold. Clause 6. The mass flow controller of clause 1, wherein the diagnostic system is further configured to compare results of the calibration operation with setpoint values ​​and tolerance values, and generate a notification message indicating at least one of the predetermined number of setpoint value adjustments and the result of the comparison. Clause 7. The mass flow controller of clause 6, wherein the diagnostic system is further configured to cause the controller to calibrate the mass flow controller based at least in part on one of the predetermined number of setpoint value adjustments, the result of the comparison, and the user input. Clause 8. The mass flow controller of clause 1, wherein the notification message further includes at least one of values ​​for temperature, valve drive, set point, sensor flow rate, gas flow time, time, fluid type, and a remaining number of set point adjustments based on total fluid time. Clause 9. A diagnostic system for calibrating a mass flow controller, comprising: a controller communicatively coupled to at least one sensor and a valve, the controller adapted to control the valve based on a predetermined setpoint value and communication information from the at least one sensor, the controller configured to determine a number of setpoint value adjustments and generate a notification message indicating the predetermined number of setpoint value adjustments. Clause 10. The diagnostic system of clause 9, wherein the predetermined number of set point value adjustments is a function of total flow time. Clause 11. The diagnostic system of clause 9, wherein the predetermined number of set point value adjustments is 128. Clause 12. The diagnostic system of clause 9, wherein the predetermined number of setpoint value adjustments is zero. Clause 13. The diagnostic system of clause 9, wherein the predetermined number of set point value adjustments is at least one of a minimum threshold and a maximum threshold. Clause 14. The diagnostic system of clause 9, wherein the controller is further configured to compare the results of the calibration operation with a setpoint value and a tolerance value, and generate a notification message indicating at least one of the predetermined number of setpoint value adjustments and the result of the comparison. Clause 15. The diagnostic system of clause 14, wherein the diagnostic system is further configured to cause the controller to calibrate the mass flow controller based at least in part on one of the predetermined number of setpoint value adjustments, a result of the comparison, and a user input. Clause 16. The diagnostic system of clause 9, wherein the notification message further includes at least one of values ​​for temperature, valve drive, set point, sensor flow rate, gas flow time, time, fluid type, and remaining number of set point adjustments based on total fluid time. Clause 17. A method for calibrating a mass flow controller, the method comprising: receiving data from at least one sensor; controlling a valve based on a predetermined setpoint value and communication information from the at least one sensor; determining a number of setpoint value adjustments; and generating a notification message indicating the predetermined number of setpoint value adjustments. Clause 18. The method of clause 17, further comprising: comparing a result of the calibration operation to a setpoint value and a tolerance value; generating a notification message indicating at least one of the predetermined number of setpoint value adjustments and the result of the comparison; and calibrating the mass flow controller based at least in part on one of the predetermined number of setpoint value adjustments, the result of the comparison, and a user input. Clause 19. The method of clause 18, wherein the predetermined number is one of a function of a minimum threshold and a maximum threshold and a total fluid time. Clause 20. The method of clause 17, wherein the notification message further includes at least one of values ​​for temperature, valve drive, set point, sensor flow rate, gas flow time, time, fluid type, and remaining number of set point adjustments based on total fluid time.

Claims

1. 1. A mass flow controller comprising: an inlet configured to receive a fluid; a flow path for the fluid to pass through the mass flow controller; a valve configured to regulate the flow of the fluid out of an outlet of the mass flow controller; at least one sensor configured to monitor fluid flow through the flow path and valve operation; a controller communicatively coupled to the at least one sensor and the valve, the controller adapted to control the valve based on a predetermined set point value and communication information from the at least one sensor, the controller further comprising a diagnostic system for calibrating the controller; The diagnostic system comprises: determining the number of set point value adjustments; generating a notification message indicating a predetermined number of setpoint value adjustments; The mass flow controller is configured as follows:

2. 2. The mass flow controller of claim 1, wherein the predetermined number of setpoint value adjustments is a function of total flow time.

3. 2. The mass flow controller of claim 1, wherein the predetermined number of setpoint value adjustments is one hundred and twenty-eight.

4. 2. The mass flow controller of claim 1, wherein the predetermined number of setpoint value adjustments is zero.

5. 2. The mass flow controller of claim 1, wherein the predetermined number of setpoint adjustments is at least one of a minimum threshold and a maximum threshold.

6. The diagnostic system comprises: Comparing the results of the calibration operation to the setpoint values ​​and tolerance values; generating a notification message indicating at least one of the predetermined number of setpoint value adjustments and a result of the comparison. The mass flow controller of claim 1 further configured to:

7. 7. The mass flow controller of claim 6, wherein the diagnostic system is further configured to cause the controller to calibrate the mass flow controller based at least in part on one of a predetermined number of setpoint value adjustments, a result of the comparison, and a user input.

8. 10. The mass flow controller of claim 1 , wherein the notification message further includes at least one of values ​​for temperature, valve drive, setpoint, sensor flow rate, gas flow time, time, fluid type, and a remaining number of setpoint adjustments based on total fluid time.

9. 1. A diagnostic system for calibrating a mass flow controller, comprising: a controller communicatively coupled to at least one sensor and a valve, the controller adapted to control the valve based on a predetermined set point value and communication information from the at least one sensor, the controller comprising: determining the number of set point value adjustments; generating a notification message indicating said predetermined number of setpoint value adjustments. A diagnostic system configured to:

10. The diagnostic system of claim 9 , wherein the predetermined number of setpoint value adjustments is a function of total flow time.

11. The diagnostic system of claim 9 , wherein the predetermined number of setpoint value adjustments is 128.

12. The diagnostic system of claim 9 , wherein the predetermined number of setpoint value adjustments is zero.

13. The diagnostic system of claim 9 , wherein the predetermined number of setpoint value adjustments is at least one of a minimum threshold and a maximum threshold.

14. The controller: Comparing the results of the calibration operation to the setpoint values ​​and tolerance values; generating a notification message indicating at least one of the predetermined number of setpoint value adjustments and a result of the comparison. The diagnostic system of claim 9 further configured to:

15. 15. The diagnostic system of claim 14, further configured to cause the controller to calibrate the mass flow controller based at least in part on one of a predetermined number of setpoint value adjustments, a result of the comparison, and a user input.

16. 10. The diagnostic system of claim 9, wherein the notification message further includes at least one of values ​​for temperature, valve drive, set point, sensor flow rate, gas flow time, time, fluid type, and remaining number of set point adjustments based on total fluid time.

17. 1. A method for calibrating a mass flow controller, comprising the steps of: receiving data from at least one sensor; controlling a valve based on a predetermined setpoint value and communication from the at least one sensor; determining a number of set point value adjustments; generating a notification message indicating a predetermined number of setpoint value adjustments; A method comprising:

18. comparing the results of the calibration operation to setpoint values ​​and tolerance values; generating a notification message indicating at least one of the predetermined number of setpoint value adjustments and a result of the comparison; calibrating the mass flow controller based at least in part on one of a predetermined number of setpoint value adjustments, a result of the comparison, and a user input; 20. The method of claim 17, further comprising:

19. The method of claim 17 , wherein the predetermined number is one of a function of minimum and maximum thresholds and total fluid time.

20. 20. The method of claim 17, wherein the notification message further includes at least one of values ​​for temperature, valve drive, set point, sensor flow rate, gas flow time, time, fluid type, and a remaining number of set point adjustments based on total fluid time.

Images