TW202334625A - Exhaust monitoring apparatus and method for substrate processing systems - Google Patents

Abstract

A gas exhaust monitoring apparatus includes a peripheral support frame and one or more collector elements. The one or more collector elements extend laterally across the peripheral support frame. The one or more collector elements include a plurality of openings configured to intake gas. A circuit board is coupled with the peripheral support frame. The circuit board includes a plurality of pressure sensors coupled to the one or more collector elements and a transmitter circuitry to transmit pressure readings from the plurality of pressure sensors. The pressure readings are utilized for computation of flow velocity of the gas.

Description

Exhaust gas monitoring apparatus and method for substrate processing systems

The present disclosure relates to exhaust monitoring devices and methods, and particularly to exhaust monitoring devices and methods for use in substrate processing systems. This application claims U.S. Provisional Patent Application No. 63/270,965 filed on October 22, 2021, and the invention is titled "EXHAUST MONITORING APPARATUS AND METHOD FOR SUBSTRATE PROCESSING SYSTEMS )", which application is hereby incorporated by reference in its entirety for all purposes.

Substrate processing systems are used to perform processes such as deposition and etching of films on substrates such as semiconductor wafers. For example, deposition may be performed using chemical vapor deposition (CVD), plasma enhanced CVD (PECVD), atomic layer deposition (ALD), plasma enhanced ALD (PEALD), and/or other deposition processes to deposit conductive films, dielectrics, Electric membrane, or other types of membranes. During deposition, the substrate is mounted on a support (e.g., a pedestal) and a gas distribution device (e.g., a showerhead) may be used to supply one or more precursor gases to the processing chamber during one or more process steps. . The gas will then exit the processing chamber via one or more exhaust passages or exhaust ducts.

The gas pressure in the exhaust pipe can be monitored by a sensor coupled to one or more openings in the pipe. Conventional sensors are located outside the tube and attached to one or more openings in the tube. Attachment may be made by one or more sensing tubes, which may be of substantially large length. The information transmitted by the sensing tube is limited by the gas pressure. Lack of local measurement can lead to overcompensation of flow requirements, exhaust pipe redesign, etc. Overcompensating can be costly and may impose limitations on the design. As such, there is a need to have online airflow monitors for obtaining localized measurements and for identifying additional airflow parameters.

According to certain embodiments, an online airflow monitoring system is provided that includes an exhaust pipe (herein referred to as a pipe) and an exhaust monitoring device coupled within the pipe. In some embodiments, an exhaust monitoring device includes a perimeter support frame, a plurality of sensor tubes, and a circuit board. In certain embodiments, the perimeter support frame includes one or more collector elements extending laterally across the perimeter support frame. In certain embodiments, one or more collector elements each include at least one opening configured to draw in gas. In other embodiments, one or more collector elements each include a plurality of openings configured to draw in gas to obtain pressure readings from various areas within the tube. In certain embodiments, the tube has a circular cross-section with one or more collector elements spanning the tube. In certain embodiments, a pair of collector elements may be separated vertically, ie, the longitudinal axis of the tube. One or more collector elements may be positioned along the diameter to obtain pressure profile measurements across the diameter of the pipe. In certain embodiments, one or more collector elements include a first plurality of openings along a direction parallel to the longitudinal axis of the tube, and a second plurality of openings along the same direction. In other embodiments, one or more collector elements include a first plurality of openings in a direction parallel to the longitudinal axis of the tube. In certain embodiments, one or more collector elements include a second plurality of openings in a direction orthogonal to the longitudinal axis of the tube.

In some embodiments, the circuit board includes a plurality of pressure sensors coupled to one or more openings in one or more collector elements. In some embodiments, the pressure sensor is an absolute pressure sensor. In other embodiments, the pressure sensor is a differential pressure sensor. In some embodiments, the pressure sensor may include multiple nozzles to facilitate pressure measurements from different areas in the collector element. In some embodiments, the circuit board may include transmitter circuitry to transmit readings from the plurality of pressure sensors to a computing device external to the exhaust gas monitoring device.

According to certain embodiments, exhaust monitoring equipment may be utilized to measure gas properties in the exhaust pipe. In some embodiments, the method utilized includes drawing gas through a first opening in a first collector element and a second opening in a second collector element of the exhaust gas monitoring device. The first collector element and the second collector element are spaced apart within the exhaust pipe. The method further includes delivering gas from both the first opening and the second opening to one or more pressure sensors located within the exhaust pipe. In certain embodiments, the method further includes utilizing the first sensor tube to deliver gas from the first opening to one or more pressure sensors. In certain embodiments, the method further includes utilizing a second sensor tube to deliver gas from the second opening to the one or more pressure sensors. The method further includes measuring the first pressure within the first sensor tube by one or more pressure sensors. The method further includes measuring the second pressure within the second sensor tube by one or more pressure sensors. The method further includes outputting a pressure reading based at least in part on the first pressure and the second pressure measured by the one or more pressure sensors. In certain embodiments, the method further includes calculating the flow rate based on predetermined values of the first pressure, the second pressure, and the density of the gas. Although the examples here focus on exhaust monitoring, this does not preclude the use of exhaust monitoring equipment in other applications.

In the accompanying drawings, the material described herein is illustrated by way of example and not by way of limitation. For the sake of simplicity and clarity, the elements depicted in the drawings are not necessarily drawn to scale. For example, the dimensions of some elements may be exaggerated relative to other elements for clarity. Also, while many physical features may be represented in simplified "ideal" forms and geometries for clarity of discussion, it is understood that actual implementations may only approximate the ideals depicted. For example, smooth surfaces and square intersections can be drawn while ignoring the finite roughness, rounded corners, and imperfect angular intersection characteristics of structures formed by nanofabrication techniques. Furthermore, where deemed appropriate, reference numbers are repeated in the drawings to indicate corresponding or similar elements.

The intelligent exhaust monitoring equipment is now described. In the following description, numerous specific details, such as structural arrangements, are set forth in order to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that embodiments of the present disclosure may be practiced without these specific details. In other instances, well-known features, such as exhaust device operation, are described in less detail to avoid unnecessarily obscuring embodiments of the present disclosure. Furthermore, it is to be understood that the various embodiments shown in the drawings are presented by way of illustration and are not necessarily drawn to scale.

In some cases, well-known methods and devices are shown in block diagram form rather than in detail in order to avoid obscuring the disclosure. Reference throughout this specification to "an embodiment" or "an embodiment" or "certain embodiments" means that a particular feature, structure, function, or characteristic described in connection with the embodiment is included in at least part of this disclosure. In one embodiment. Thus, the appearances of the terms "in an embodiment" or "in an embodiment" or "in certain embodiments" in various places throughout this specification do not necessarily refer to the same embodiment of the present disclosure. Furthermore, the particular features, structures, functions or characteristics may be combined in any suitable manner in one or more embodiments. For example, a first embodiment may be combined with a second embodiment as long as any specific features, structures, functions or characteristics associated with the two embodiments are not mutually exclusive.

The terms "coupled" and "connected" along with their derivatives may be used herein to describe the functional or structural relationship between two components. These terms are not intended as synonyms for each other. Rather, in particular embodiments, "connected" may be used to indicate that two or more elements are in direct physical, optical, or electrical contact with each other. "Coupled" may be used to indicate that two or more elements are in physical, electrical, or magnetic contact with each other, either directly or indirectly (with other intervening elements between the two or more elements), and/or to indicate that two or more elements are in physical, electrical, or magnetic contact with each other, either directly or indirectly (with other intervening elements between the two or more elements). More elements collaborate or interact with each other (e.g., like in a cause-and-effect relationship).

As used herein, the terms "on," "under," and "on" refer to the relative position of one component or material with respect to other components or materials where such physical relationships are of concern. Unless "directly" or "directly" is used to modify these terms, one or more intermediate components or materials may be present. A similar distinction will be made in the context of component assemblies. As used throughout this description and in the claims, a list of items linked by the terms "at least one of" or "one or more of" may mean any combination of the listed terms.

The term "adjacent" as used herein generally refers to a location where an object is adjacent (e.g., immediately adjacent or proximal in the case of one or more objects between them) or adjacent (e.g., adjacent to) another object.

Unless otherwise indicated in the clear context of their use, the terms "substantially equivalent," "approximately equivalent," and "approximately equivalent" mean that there is only incidental variation between the two items so described. In the art, such variations typically do not exceed +/-10% of the quoted value.

Existing exhaust monitoring systems for semiconductor device manufacturing tools are cumbersome and functionally limited. Existing exhaust monitoring systems collect data from a sensor tube connected to the exhaust pipe and determine the external pressure in a computing device located outside the exhaust pipe. The air pressure is not measured in the area within the exhaust pipe but at peripheral points along the pipe. Cross-sectional measurements of air pressure are then estimated from the perimeter measurements. There is often a significant difference between pressure measurements taken along the longitudinal axis and the perimeter of the tube. Such differences may often lead to an overestimation of exhaust system requirements because gas velocities at the periphery do not accurately describe gas velocities at the center of the tube. These differences can result in significant increases in operating costs. Furthermore, existing exhaust pressure monitoring systems lack the ability to measure gas flow rates, which are important for estimating exhaust pipe conductivity (eg, airflow volume). Measurements of conductivity can help determine whether existing exhaust pipes are sufficient to achieve the necessary flow capacity or if additional exhaust pipes are needed.

In order to cope with the above-mentioned limitations, an in-line exhaust monitoring device that can be implemented in an exhaust pipe, a pipe, or a duct of a semiconductor manufacturing equipment is disclosed. According to embodiments of the present disclosure, an exhaust gas monitoring device includes a perimeter support frame and one or more collector elements coupled to the perimeter support frame. In certain embodiments one or more collector elements may be custom-made bars or rods. In certain embodiments, one or more collector elements extend laterally across the perimeter support frame. In certain embodiments, one or more collector elements include a plurality of openings configured to draw in gas or allow gas to flow through attached tubes coupled to sensors (eg, pressure sensors, temperature sensors, etc.) . In some embodiments, the circuit board is coupled to the perimeter support frame. In some embodiments, the circuit board includes a plurality of pressure sensors coupled to one or more collector elements and a transmitter (eg, transmitter circuit) to transmit readings from the plurality of pressure sensors. In some embodiments, the circuit board may include one or more flow sensors in addition to the pressure sensor.

In certain embodiments, the exhaust monitoring device may further include a separately movable damper coupled within the tube. In some embodiments, the damper can actively control the total airflow within the tube. In some embodiments, readings from the pressure sensor may be transmitted via a wired connection, or wirelessly, to control the damper to increase (if not previously set to maximum flow) or decrease the total airflow.

For example, semiconductor manufacturing equipment such as etch or deposition tools may include numerous exhaust pipes. The exhaust pipe can be coupled to various chambers within the tool (process chamber, vacuum transfer chamber, equipment front end module (EFEM), etc.). Exhaust pipes from different parts of the tool can be coupled into a unified exhaust or to different sub-exhaust systems that feed into a unified exhaust. In some cases, the exhaust pipe may feed into different systems, some of which may require exhaust and some may not. The exhaust pipes may have the same or different cross-sectional areas and may be designed to accommodate the throughput depending on the volume of pumped gas. In some embodiments, flow rates within different sub-exhaust pipes may be individually programmed to increase efficiency. The dampers of the exhaust gas monitoring system in certain embodiments may be incorporated into one or more exhaust ducts and the dampers may be controlled to increase airflow throughput, efficiency, uniformity across different ducts, or all of the above.

FIG. 1A illustrates a schematic diagram of a substrate processing system 100 including one or more exhaust monitoring devices 101 within an exhaust system 103 , in accordance with an embodiment of the present disclosure. In the illustrative embodiment, exhaust system 103 is coupled to processing tool 105 . In some examples, exhaust system 103 may be referred to as plant vacuum system 103 . In some embodiments, exhaust system 103 includes a plurality of exhaust lines (eg, exhaust lines 107A-107F), and each exhaust line includes exhaust monitoring device 101 . Details of the exhaust gas monitoring device 101 will be described here.

In some embodiments, exhaust lines 107A-107F (collectively, "exhaust lines 107") may be exhaust pipes coupled between various components within the processing tool 105 and the exhaust receptacle 109. For example, processing tool 105 may include at least one processing chamber 105A (eg, processing module), transfer chamber 105B (eg, vacuum transfer module or VTM), equipment front-end module 105C (or EFEM 105C), and an air box 105D. In the illustrative embodiment, exhaust line 107A is coupled to processing chamber 105A, exhaust lines 107B, 107C, and 107D are coupled to transfer chamber 105B, and exhaust line 107E is coupled to EFEM 105C. And exhaust line 107F is coupled to air box 105D.

It may be necessary to maintain necessary flow rates in each exhaust line 107A~107F. In fact, each exhaust line 107A-107F may have different throughput requirements that may be met, for example, by changing the size of the pipe. In certain embodiments, the insertion of a damper (not shown) in each exhaust monitoring device 101 may enable the exhaust system 103 or plant vacuum system 103 to operate more efficiently.

In some embodiments, the total airflow in the exhaust system 103 may be monitored and controlled by individual exhaust monitoring devices 101 in each exhaust line 107A-107F. In some embodiments, the dampers in each exhaust line 107A-107F may be individually controlled by external controller 111. In some embodiments, the external controller 111 may communicate with transmitters within one or more exhaust monitoring devices 101 to rotate each damper to change airflow. In some embodiments, controller 111 may control other substrate processing systems in addition to substrate processing system 100 . In certain embodiments, exhaust monitoring device 101 may communicate directly (or indirectly via an intermediary device such as controller 111) with other exhaust monitoring systems in other substrate processing tools. In certain embodiments, a centralized system may be configured to monitor and/or control exhaust in an entire fleet of substrate processing tools via one or more exhaust monitoring devices 101 or controllers 111 .

Figure IB illustrates an isometric view of exhaust gas monitoring device 101, in accordance with certain embodiments. According to some embodiments, the exhaust monitoring device 101 is designed to be installed within the exhaust pipe/duct to measure the properties of the in-line airflow. As such, in the illustrative embodiment, exhaust gas monitoring device 101 includes perimeter support frame 102 and one or more collector elements, such as collector element 104 coupled or connected to perimeter support frame 102 . As shown, in some embodiments, the collector element 104 extends laterally across the upper portion of the perimeter support frame 102 . In some embodiments, collector element 104 includes openings 106 and 108 . Structural details of openings 106 and 108 are further described in Figures 1D and 1E. In some embodiments, a single opening 106 and a single opening 108 may be sufficient. However, multiple openings 106 and 108 may provide measurements across different points. A plurality of openings 106 and 108 extend through the collector element 104 and are designed to interface with the sensor tube (eg, via insertion) and to admit gas. As shown, sensor tube 110A is coupled to collector element 104 via opening 106 .

In some embodiments, the circuit board 112 is coupled to the support plate 130 of the peripheral support frame 102 . In the illustrative embodiment, circuit board 112 includes at least one pressure sensor, such as pressure sensor 114 coupled to collector element 104 via sensor tube 110A. In an embodiment, circuit board 112 further includes a transmitter 126 to transmit readings from pressure sensor 114 to another device (eg, controller 111 in FIG. 1A , a computer, or another centralized control or monitoring system ). In some embodiments, circuit board 112 may include at least one airflow sensor in addition to pressure sensor 114 . In some embodiments, a temperature sensor may also be included.

FIG. 1C illustrates an isometric view of perimeter support 102 in accordance with an embodiment of the present disclosure. The circuit board 112 and sensor tube are not shown in Figure 1C. In the illustration, a support plate 130 for mounting the circuit board can be seen.

In an embodiment, the perimeter support frame 102 includes an upper ring structure 116 (hereinafter ring structure 116). In the illustrative embodiment, ring structure 116 is circular. As shown, collector element 104 extends across the diameter of ring structure 116 . In other embodiments, the ring structure 116 may be oval, square, rectangular, or other shapes that will allow for proper interface with the airflow duct. The placement of the collector element 104 across the diameter advantageously achieves a radial profile for pressure and flow measurements. In certain embodiments, the number of openings 106 or 108 depends on the diameter _DR of the ring structure 116 and the diameter of the opening 106 . In some embodiments, _DR ranges between 3 inches and 9 inches. In certain embodiments, _DR is at least 9 inches but less than 18 inches. In some embodiments, the number of openings 106 also depends on the number of measurement locations required. In some embodiments, the number is between 2 and 4. In some embodiments, the number of openings 106 is greater than four. In the illustrative embodiment, the number of openings 106 exceeds the number of openings 108 . In other embodiments, the number of openings 108 exceeds the number of openings 106 . In the exemplary embodiment, one of the openings 106 is located at the axis of the peripheral support frame 102 . As will be discussed below, the opening 106 at the axis facilitates the detection of airflow at maximum pressure (and maximum flow rate). In the illustrative embodiment, collector element 104 includes both openings 106 and 108 . Opening 108 is designed to provide a measurement of the airflow component. The difference between the measurements obtained using openings 106 and 108 may be used for calibration of one or more pressure sensors. The openings within collector elements 104 and 120 associated with portion 117 will be described in further detail below.

Figure 1D shows an enlarged isometric view of portion 117 of collector element 104 in Figure 1C. Openings such as openings 106A, 106B, and 106C have an orientation parallel to the longitudinal axis of peripheral support frame 102 (along the Z direction). In some embodiments, openings 106A and 106B extend from top surface 104A to bottom surface 104B. As shown, openings 106A and 106B extend across the vertical thickness T ₁ of collector element 104 . T ₁ spans a distance between top surface 104A and bottom surface 104B. Generally speaking, the lower end of opening 106A is configured to draw gas and the upper end of opening 106A is configured to couple to a sensing tube (not shown). However, as will be discussed below (in Figure 3E), the placement of the sensing tube depends on the direction of the air flow. In the illustrative embodiment, openings 106A and 106B are circular and have a diameter D ₁ between 1 mm and 10 mm. In certain embodiments, D ₁ is substantially uniform across vertical thickness T ₁ .

In the illustrative embodiment, openings 106A, 106B, and 106C are diametrically spaced apart (along the X direction) by a distance S ₁ . In some embodiments, adjacent openings 106A, 106B, and 106C are equidistant from each other. For example, the openings 106A and 106B are separated by a distance S ₁ , and the openings 106B and 106C are also separated by a distance S ₁ , and S ₁ may be between 0.2 cm and 10 cm. In some embodiments, the spacing between adjacent pairs of openings (eg, 106A and 106B, and 106B and 106C) may be inconsistent. The placement of openings 106A, 106B, and 106C in portion 117 may be designed for measurements at specific locations within an enclosure in which exhaust gas monitoring device 101 may be accommodated. In the illustrative embodiment, opening 106A may be at the axis of collector 104 (along the Z direction).

In certain embodiments, openings 108A, 108B, and 108C have an orientation orthogonal to the longitudinal axis of peripheral support frame 102 (along the Y direction). In some embodiments, openings 108 extend from side wall surface 104C to side wall surface 104D. As shown, the opening 108 extends across the lateral thickness T ₂ of the collector element 104 . A first end of opening 108A is configured to draw in gas and an opposite end of opening 108A is configured to couple to a sensing tube (not shown). However, as will be discussed below (in Figure 3E), the placement of the sensing tubes depends at least in part on the direction of the air flow. In the illustrative embodiment, openings 108A and 108B are circular and have a diameter D ₂ , _which may be between 1 mm and 10 mm. In certain embodiments, _D2 is substantially uniform across transverse thickness _T2 . In certain embodiments, D ₂ and D ₁ are substantially equal.

In the illustrative embodiment, openings 108A, 108B, and 108C are diametrically spaced apart (along the X direction) by a distance S ₂ . In some embodiments, adjacent openings 108A, 108B, and 108C are equidistant from each other. For example, openings 108A and 108B are spaced apart by a distance S ₂ , and openings 108B and 108C are also spaced apart by a distance S ₂ , and S ₂ may be between 0.2 and 10 cm. In some embodiments, the spacing between adjacent pairs of openings 108 (eg, 108A and 108B, and 108B and 108C) may be inconsistent. The placement of openings 108A, 108B, and 108C in portion 117 may be designed for measurements at specific locations within the enclosure in which the exhaust device may be accommodated.

The minimum spacing between opening 108A and adjacent opening 106B or 106C is a spacing that prevents intersection. In certain embodiments, the spacing is at least 1 mm. In other embodiments the separation may be less than 1 mm but greater than 0.1 mm. A configuration in which a vertical opening, such as opening 106A, is placed between a pair of lateral openings, such as openings 108C and 108B, ensures that the vertical opening does not intersect with the lateral opening. Thus, a minimum separation between 1 mm but greater than 0.1 mm is sufficient to prevent intersection between vertical and transverse openings.

In Figure 1D, _T1 is substantially uniform across the vertical thickness _T1 . In other embodiments, as illustrated in structure 119 in Figure IE, collector element 104 has a top surface 104A that is wider than a bottom surface 104B. Structure 119 has one or more properties of portion 117 of collector element 104 (shown in Figure ID), such as lateral openings 108 and vertical openings 106. The structure 119 has a narrower bottom surface 104B than the top surface 104A, which is beneficial to reducing the total cross-sectional area of the bottom surface 104B. The reduced total cross-sectional area of bottom surface 104B reduces the net gas impedance within the tube housing the perimeter support frame. In some embodiments, bottom surface 104B has an area that is approximately 25% to 65% less than the area of top surface 104A. As shown, bottom surface 104B has a lateral thickness T ₃ that is less than the lateral thickness T ₂ of top surface 104A. In some embodiments, T ₃ is substantially equal to or greater than diameter D1 of openings 106A and 106B.

In certain embodiments, the perimeter support frame 102 may include one or more collector elements to facilitate flow velocity measurements as well as pressure measurements at multiple locations along the direction of air flow. Referring again to FIG. 1C , the perimeter support frame 102 further includes a pair of vertical support posts 118A and 118B (hereinafter referred to as support posts 118A and 118B) on diametrically opposite ends of the ring structure 116 . In some embodiments, support posts 118A and 118B extend away from the annular structure 116 . In certain embodiments, additional collector elements 120 are coupled to support columns 118A and 118B, as shown.

In certain embodiments, collector element 120 has one or more features of collector element 104 described with respect to (Figures ID and IE). In the illustrative embodiment, collector element 120 has one or more characteristics of collector element 104 (described with respect to FIG. 1E ), such as vertical and lateral thickness, shape, etc. In other embodiments, collector element 120 may have different vertical and lateral thicknesses than collector element 104, T ₁ and T ₂ respectively. In some embodiments, collector element 120 includes openings 122 and 124 . In the exemplary embodiment, the spatial arrangement of openings 122 is substantially the same as openings 106 . In some embodiments, the spatial arrangement of openings 124 is substantially the same as openings 108 . In certain embodiments, as shown, collector element 104 can be above and parallel to collector element 120 . Collector element 120 may be positioned below collector element 104 to provide pressure measurements at approximately the same but separated radial locations along the longitudinal axis (z-axis in Figure C). Pressure measurements at the same radial position are preferred to obtain flow rate measurements substantially parallel to the longitudinal axis. As shown, when collector element 104 is above and parallel to collector element 120, the net impedance to airflow across the length of perimeter support frame 102 (along the Z direction) is also reduced.

In some embodiments, collector elements 104 and 120 are vertically separated from each other by a distance S ₃ . In certain embodiments, _S3 is between 5 cm and 100 cm. In certain embodiments, S ₃ is between 15 cm and 30 cm. In some such embodiments, circuit board 112 remains as shown in Figure IB regardless of the length of _S3 . As shown in FIG. 1B , sensor tube 110B is shortened or extended to reach collector element 120 . Referring to Figure 1C, in embodiments, _S3 may depend on diameter _DR . In some embodiments, a larger _DR may be associated with a larger S ₃ . A _DR ranging between 3 inches and 9 inches can be related to an _S3 in the range of 5 cm to 50 cm. A _DR varying between 9 inches and 18 inches can be related to an _S3 in the range of 50 cm to 100 cm. In other embodiments, a _DR ranging between 3 inches and 9 inches can be associated with an _S3 in the range of 5 cm to 10 cm.

In some embodiments, perimeter support frame 102 may be made from a polymer such as polyvinyl chloride (PVC). In embodiments, the design of the perimeter support frame 102 may be drawn and 3D printed. In some embodiments, the perimeter support frame 102 further includes a plurality of pivot plates 132 extending laterally from the ring structure 116 . Four rotating plates are shown, but the number of rotating plates 132 may vary with the diameter of the ring structure 116 . Each of the rotating plates 132 includes a respective opening 134 for securing the ring structure 116 to the tube (as discussed herein). In some embodiments, the perimeter support frame 102 has two rotating plates. In some embodiments, perimeter support frame 102 has three rotating plates. In some embodiments, perimeter support frame 102 has more than four pivot plates.

In the illustrative embodiment, as will be discussed below, support columns 118A and 118B further include respective openings 136 that facilitate gas pressure measurement using external pressure measurement tools. Opening 136 may be round as shown. According to certain embodiments, opening 136 may have a diameter of between 1 mm and 10 mm.

FIG. 1F illustrates an enlarged isometric view of portion 125 of exhaust gas monitoring device 101 in FIG. 1B . In an embodiment, sensor tube 110A is coupled between opening 106C and first nozzle 114A of pressure sensor 114 . In some embodiments, pressure sensor 114 is a differential pressure sensor. In some embodiments, differential pressure sensor 114 measures the pressure difference between two different points along the path of the air flow. The two points may be located at two different collectors, such as collector element 104 and collector element 120 (as shown in Figure IB). The pressure difference may be measured by pressure sensor 114 using sensor tubes 110A and 110B. In the illustrative embodiment, sensor tube 110B is coupled between second nozzle 114B of pressure sensor 114 and an opening in collector element 120 (not visible in FIG. 1F but can be seen, for example, in FIG. 1A to).

Gas entering sensor tubes 110A and 110B along the flow direction (z-direction in Figure IF) can be used to estimate flow rate using differential pressure and gas density. Flow rate can be calculated from flow velocity and flow cross-sectional area without the need for a flow meter (see Figure 3C). Multiple sensing points in the collector element 104 in combination with two or more differential sensors can also be used to obtain gas velocity profiles. Gas velocity profiles can be used to improve flow rate calculation accuracy.

In some embodiments, the differential pressure sensor uses Bernoulli’s equation to measure the flow of gas in the tube. A differential pressure sensor introduces a contraction in the tube to produce a pressure drop across two points within the tube. Pressure drop is the difference in pressure between the upstream and downstream sides of a differential pressure sensor. When the flow rate increases, a larger pressure drop occurs. The pulse line routes the upstream and downstream pressures from the differential pressure sensor to a manometer tube that measures the pressure difference in the upstream and downstream sides of the restrictor. The difference in measured pressure (i.e., differential pressure) is used to determine flow rate. In other embodiments, pressure sensor 114 is an absolute pressure sensor. Unlike differential pressure sensors, absolute pressure sensors measure the pressure at a single point relative to a calibrated vacuum level. In the illustrative embodiment, sensor tubes 110A and 110B provide measurements of pressure at two points at two different collector locations. It will be appreciated that sensor tubes 110A and 110B can each be of different lengths without adversely affecting the accuracy of the measurements. In some embodiments, the lengths of the many sensor tubes can vary by up to 50%.

FIG. 1G illustrates an enlarged isometric view of portion 127 of exhaust gas monitoring device 101 in FIG. 1B . In the illustrative embodiment, sensor tube 110C is coupled between opening 124A of collector element 120 and nozzle 128A of pressure sensor 128 . In other examples, sensor tube 110C may be coupled between the upper end (hidden) of opening 122A and nozzle 128A of pressure sensor 128 .

As shown, sensor tube 110C is connected to the backside of opening 124A. In some embodiments, pressure sensor 128 is a differential pressure sensor. In other embodiments, pressure sensor 128 is an absolute pressure sensor. It will be appreciated that sensor tube 110C may have a different length compared to the length of sensor tubes 110A and 110B (in Figure IF). As will be discussed below in Figure 3H, calibration between different sensor tubes (eg, 110A, 110B, and 110C) can be performed by coupling to the same opening but to different pressure sensors.

FIG. 2A illustrates an isometric view of the exhaust gas monitoring device 101 of FIG. 1B , according to certain embodiments of the invention. Figure 2A is an isometric view of the back side of the exhaust gas monitoring device 101. As shown in the figure, the circuit board is mounted on the support plate 130 of the peripheral support frame 102 . In the illustrative embodiment, support plate 130 includes a pair of extensions 130A and 130B coupled to ring structure 116 . Extensions 130A and 130B are designed to provide mechanical support for circuit board 112 and include the same material as the perimeter support frame. As shown, the circuit board 112 is positioned within the ring structure 116 to prevent components of the circuit board 112 from contacting the tube into which the perimeter support frame 102 is designed.

The exhaust monitoring device 101 is designed to operate in an environment for measuring gas properties of corrosive by-products. As such, there is a need to protect circuit board 112 and internal components such as pressure sensor 114 and wireless transmitter 126 from corrosive by-products to which exhaust gas monitoring device 101 may be exposed during operation.

Figure 2B is an isometric view of the exhaust gas monitoring device 200 having all the features of the exhaust gas monitoring device 101 (in Figure 2A). FIG. 2B shows the circuit board 112 in FIG. 2A being encapsulated in resin 202 . In some embodiments, resin 202 may include a polymer coating that is insulating and non-reactive with corrosive gases. According to some embodiments, resin 202 may be up to 1 mm thick.

Figure 3A is an isometric view of a pipe structure 300 (eg, an exhaust duct or tube) designed to retrofit a device such as exhaust monitoring device 101 (described with respect to Figures 1A-1F). As shown, tube structure 300 includes cylindrical tube 302 . In certain embodiments, tube 302 has a circular cross-section to allow laminar flow for optimal airflow. Depending on the application, tube 302 may have a diameter between 2 inches and 10 inches. In certain embodiments, the tube structure 300 further includes a mounting bracket 304 attached to the end 308 of the tube 302 . In some embodiments, the mounting bracket 304 is designed to couple to a device (such as, for example, the exhaust gas monitoring device 101 described above). In some embodiments, the mounting bracket 304 includes a plurality of bolt holes 306 to facilitate coupling to the exhaust gas monitoring device 101 (described above). In embodiments, when the tube 302 includes a metal construction, the mounting bracket 304 may be welded to the outer surface of the tube 302 . In other embodiments, the mounting bracket 304 is fabricated as a component of the tube structure 300 regardless of the material of the tube 302 . Tube 302 may further include at least one opening, such as opening 307, to measure pressure at the periphery of the tube. One end of a sensor tube (not shown) can be attached to opening 307 and the other end can be attached to a pressure sensor located outside of tube 302 . In the illustrative embodiment, tube 302 includes two openings 307 that are substantially completely separate. In such an embodiment, opening 307 may facilitate simultaneous pressure measurements at two substantially opposite ends of tube 302 .

FIG. 3B is an isometric view of device 320 including exhaust monitoring device 101 coupled to pipe structure 300 at end 308 . Device 320 may be an example of an online gas monitoring system designed to measure gas velocity in exhaust gases from a substrate processing system, such as, for example, substrate processing system 100 . In the illustrative embodiment, the ring structure 116 of the exhaust gas monitoring device 101 is circular and sits on the mounting bracket 304 . As shown in the figure, individual rotating plates 132 of the exhaust gas monitoring device 101 are fixed to respective bolt holes 306 using bolts 309 (not visible in the figure). In some embodiments, support posts 118A and 118B are confined within ring structure 116 . In an embodiment, openings 136 in support posts 118A and 118B are aligned with openings 307 in tube 302 (shown in Figure 3A). The alignment between openings 136 and 307 facilitates external measurement of gas pressure in tube 302 during operation. An external pressure measurement tool, such as an absolute pressure sensor, may be coupled to opening 307 via tubing. Gas flowing into openings 136 in respective support columns 118A and 118B may be directed to respective absolute pressure sensors by respective tubes. The measurement of the pressure near opening 136 using a measuring tool remote from opening 136 constitutes an external measurement of the gas pressure in tube 302 . It should be understood that support posts 118A and 118B may contact the sidewalls of tube 302. In this manner, the surfaces of support posts 118A and 118B can match the curvature of tube 302. The matching curved surfaces between the support posts 118A and 118B and the tube 302 enable flush contact without gaps. In some embodiments, openings 136 and 307 may be circular, with opening 136 having a smaller diameter than opening 307 . The smaller diameter ensures that the outer tube can be secured without gaps to prevent the loss of gas from opening 307.

In certain embodiments, ring structure 116 has an inner diameter D _I that is the same or substantially the same as inner diameter D _T of tube 302 . In certain embodiments, when D _I is greater than or equal to D _T then ring structure 116 does not obstruct air flow, although collector elements 104 and 120 themselves partially obstruct air flow.

In embodiments where _DI is less than _DT , support posts 118A and 118B may not contact the sidewalls of tube 302. In some such embodiments, the outer tube coupled to the absolute pressure sensor will protrude within the interior of tube 302.

Figure 3C illustrates a cross-sectional plan view of device 330. Device 330 is an example of an online gas monitoring system (FIG. 3B) and further includes a plurality of sensor tubes (eg, sensor tubes 110A, 110B, etc.). As shown, tube 302 has a cross-sectional area A _T within inner wall 302A of tube 302 . As shown, the collector element 104 has an area _ACE and the support plate 130 has an effective surface area _ASP . Airflow within tube 302 is obstructed by the presence of collector element 104 and support plate 130 for the circuit board (not visible) and sensor tubes (eg, 110A and 110B).

The opening area of the gas flow tube 302 is given by the difference between A _T and the sum of A _SP and A _CE and the effective surface area of the sensor tube (eg, sensor tubes 110A, 110B, etc.). A _CE needs to be as small as possible to facilitate the collection of traffic data but large enough to be physically rigid. It will be appreciated that collector element 104 has substantially the same plan view cross-section as collector element 120 (not visible in the drawings) to minimize any reduction in airflow through tube 302 . Collector element 120 is directly below collector element 104 to provide pressure measurements at the same radial position (although separated along a longitudinal axis orthogonal to the plane of the drawing). Measurement of pressure at the same radial location may preferably be used to obtain flow rate measurements. When collector element 120 is offset relative to collector element 104, then the overall flow reduction may be greater because the difference in opening area A _T - ( _ASP + _ACE ) is reduced. However, in some embodiments, collector element 120 is offset relative to collector element 104 by up to a distance equal to one half of the inner diameter of tube 302 ( _DT in Figure 3B).

Support posts 118A and 118B are invisible and tied directly beneath collector element 104 . In the exemplary embodiment, support posts 118A and 118B do not increase the cross-sectional area of collector element 104 .

It will be appreciated that the presence of the exhaust gas monitoring device 101 within the duct structure 300 impedes airflow by less than 5% under steady-state flow disturbance conditions. The reduction in airflow is also a function of gas temperature. However, for gas temperatures less than 25 degrees Celsius, a flow reduction of less than 5% may be observed.

Figure 3D is a method 340 of measuring gas pressure in a device such as exhaust monitoring device 101.

Method 340 begins at operation 341 by flowing gas into a tube, wherein the flow causes the gas to enter an open first end of a collector element of an exhaust gas monitoring device within the tube. Method 340 continues with operation 342 by forcing gas entering the opening to be directed into a sensor tube coupled at the second end of the opening. The second end is relative to the first end. Gas flow is maintained in the sensor tube by positive pressure from the gas flowing in the tube. Direct the gas to the pressure sensor. Method 340 ends at operation 343 by using a pressure sensor to measure the pressure of gas flowing in the sensor tube.

Figure 3E is a schematic diagram illustrating the operation of device 350 including exhaust monitoring device 101 within duct 302 described with respect to Figure 3B, according to certain embodiments. In an embodiment, exhaust gas, such as gas 351 (indicated with arrows) flows within tube 302 and enters one or more openings in collectors 120 and 104 . In certain embodiments, gas 351 passes through opening 122A of collector 120 , into the inlet of sensor tube 110C and is directed to pressure sensor 128 . The positive pressure within tube 302 maintains the flow of gas 351 in the positive y direction in sensor tube 110C. The positive pressure ensures that some of the gas 351 flowing into one end 352 of opening 122A continues to flow into sensor tube 110C coupled to the opposite end 353 of opening 122A. Pressure sensor 128 senses gas 351 impinging on the internal sensing element and measures the pressure of gas 351 within tube 110C. Because sensor 128 is close to opening 122A, opening 122A is the approximate measurement location. In an embodiment, dynamic measurement (or real-time continuous measurement) of gas pressure by pressure sensor 128 is facilitated by the continued flow of gas 351 in sensor tube 110C. In an embodiment, continuous flow within sensor tube 110C is achieved because gas 351 exits pressure sensor 128 through openings (not shown) in sensor 128 .

Gas 351 also passes through opening 106A in collector 104, enters the inlet of sensor tube 110A and is directed to pressure sensor 114. Gas 351 flows into one end 354 of opening 106A and into sensor tube 110A coupled to an opposite end 355 of opening 106A. The positive pressure within tube 302 ensures that gas 351 continues to flow within sensor tube 110A. Pressure sensor 114 senses gas 351 impinging on the internal sensing element and measures the pressure of gas 351 flowing within sensor tube 110A. Because pressure sensor 114 is close to opening 106A, opening 106A is the approximate measurement location. In embodiments, dynamic measurement (or instantaneous continuous measurement) of the gas pressure at pressure sensor 114 is facilitated as long as there is continued flow of gas 351 in tube 110A. The continuous flow is achieved because the gas 351 exits the pressure sensor 114 through an opening (not shown) in the sensor 114 . In the exemplary embodiment, openings 106A and 122A are located at the axis of exhaust monitoring device 101 . The openings at the axial centers of the collector elements 104 and 120 enable detection of the maximum pressure of the gas 351 flowing in the tube 302 . In embodiments in which laminar flow exists in the cylindrical tube 302 , the maximum flow rate of the gas 351 is at the axis of the cylindrical tube 302 . In certain such embodiments, the maximum flow rate is related to the maximum pressure.

In the illustrative embodiment, openings 106A and 122A are both oriented along the same direction (z-direction). This allows pressure sensors 114 and 128 to measure components of gas 351 flowing in substantially the same direction (eg, the z-direction in the figure). The vertical spacing S ₃ between collector element 120 and collector element 104 may be sufficient to allow a substantially vertical component of gas 351 to enter opening 106A. As discussed above, _S3 may be a function of the diameter of tube 302 ( _DT in Figure 3B).

In the illustrative embodiment, openings 106A and 122A are a respective pair of openings in collector elements 104 and 120, respectively. As shown, openings 106A and 122A are vertically or substantially vertically aligned. In some such embodiments, other pairs of openings along collector elements 104 and 120 that are not at the axis (eg, 122AB and 106AB - not shown) are also vertically or substantially vertically aligned. Vertical alignment between individual openings in the group of openings 106 in the collector element 104 and individual openings in the group of openings 122 in the collector element 120 (such as that shown in FIG. 1C ) may facilitate to provide correlated pressure measurements for a group of paired openings separated by the same distance S ₃ . Such correlated pressure measurements may help provide a pressure measurement profile along the diameter of tube 302.

The difference in pressure between openings 122A and 106A enables measurement of the gas flow rate. The difference in pressure measurements between pressure sensors 128 and 114 coupled to openings 122A and 106A, respectively, can be used directly to calculate flow rate. In some embodiments, calculations may be performed via circuit board 112 . In some embodiments, data from each pressure sensor 128 and 114 may be transmitted to a computer external to tube 302 for flow rate calculations. In some embodiments, the difference in detected pressure measurements may be used to calculate the flow rate based on the following equation (1):

V ² =2[P ₂ -P ₁ ]/rho (1)

where V is the flow rate, P ₁ and P ₂ are the pressure readings at openings 122A and 106A respectively, and rho is the density of the gas flowing in tube 302 (or the weighted density of different gas components). In one example, the density of nitrogen at standard temperature and pressure (STP) may be utilized in the calculation. In an embodiment, the velocity is the average flow velocity calculated between openings 122A and 106A.

In some embodiments, the gas flow rate can be obtained from a test setup in which the tube 302 can be attached at the base to a fan capable of generating a flow of calibration gas (eg, _N2 or air). The flow rate of the calibration gas can be varied to assist in measuring a range of flow rates for a given tube size. The flow rate information can be utilized to implement correct fan sizing for achieving airflow (eg, fan speed for achieving a specific cubic flow rate of gas per minute). Evaluating accurate fan sizing can eliminate the implementation of unnecessarily larger exhaust fans in exhaust lines within systems such as those illustrated in Figure 1A. An accurate assessment can help reduce costs, prevent lengthy maintenance downtime, and save space in systems where smaller exhaust fans can be utilized in place of larger ones.

In certain embodiments, sensor tube 110D may be coupled to lateral opening 124A within collector element 120, as illustrated in FIG. 3F. In certain such embodiments, gas 351 enters along transverse opening 124A at end 356 and enters tube 110D at end 357 . The method of pressure measurement is substantially the same as that described with respect to Figure 3E. In some such embodiments, the cross flow velocity of gas 351 (along the y direction) can be calculated by measuring the pressure at opening 124A.

In some embodiments, as illustrated in Figure 3G, sensor tube 110A may be coupled to a second nozzle 128B (hidden behind nozzle 128A). In some embodiments, pressure sensor 128 may be a differential pressure sensor that measures and compares pressure readings from two points. In some embodiments, pressure readings may be transmitted to an external input device (eg, a microcontroller). In some embodiments, pressure readings obtained from two different ends 352 and 354 may be transmitted from a pressure sensor to a computing block within or external to the circuit board 112 to calculate the flow rate. In other embodiments, the pressure sensor 128 is an absolute pressure sensor having two input nozzles 128A and 128B. The flow rate measurement can be calculated from the pressure readings obtained from the two different openings 106A and 122A and the input nozzles 128A and 128B.

In another embodiment, as illustrated in Figure 3H, sensor tube 110C (shown in Figure 3E) is further coupled with additional sensor tubes, such as sensor tube 110E. In the illustrative embodiment, sensor tube 110E is coupled between sensor tube 110C and pressure sensor 114 . Sensor tube 110E provides additional access for gas 351 into opening 122A to flow to additional pressure sensors, such as pressure sensor 114 . In the illustrative embodiment, gas 351 entering opening 122A may flow to pressure sensors 114 and 128 simultaneously. Because sensor tube 110E has a longer path length compared to sensor tube 110C, simultaneous pressure measurements using pressure sensors 114 and 128 can be provided at a single measurement location, such as at end 352 of opening 122A. means of pressure difference (if any). Such measurements can provide sensitivity of the pressure measurement to the length of the sensor tube and can be used to calibrate pressure sensors 114 and 128 .

The device 350 described with respect to Figures 3E-3H provides a means to dynamically measure pressure and calculate flow velocity within tube 302. Referring again to Figure 3C, a plurality of sensor tubes may be coupled between each pressure sensor and each of a plurality of openings distributed along the length of collector elements 104 and 120 (not visible). In some such embodiments, a pair of measurement locations corresponding to an opening on each collector element 104 and 120 may be selected to provide a measurement of velocity parallel to the longitudinal axis (z-direction). A set of paired measurement locations along the entire length of collector elements 104 and 120 may be used to obtain pressure profile measurements. The velocity profile measurement across tube 302 may be calculated from the pressure profile measurement. In the illustrative embodiment, collector 104 is positioned along the diameter of tube 302 to provide maximum measurement range within tube 302 .

Although the tool and exhaust are located at opposite ends of each other as shown in Figures 3E-3H, the orientation of the tool and exhaust relative to collector elements 104 and 120 can be reversed. In an inverted configuration. Gas 351 will be directed in the negative z direction. Referring again to Figure 3E, in some such embodiments, tubes 110A and 110C can be inserted into ends 354 and 352, respectively, to measure gas 351 flowing in the opposite direction (-z direction).

Figure 3I is a flow diagram of a method 360 of measuring one or more airflow properties in tube 302 (Figure 3B) by using exhaust monitoring device 101. In embodiments, tube 302 may be an exhaust duct. Method 360 begins at operation 361 by drawing gas through a first opening in a first collector element and a second opening in a second collector element of the exhaust gas monitoring device. The first collector element and the second collector element are spaced apart within the exhaust duct. Method 360 continues at operation 362 by delivering gas from the first opening and the second opening to one or more pressure sensors located within the exhaust conduit. Method 360 continues with operation 363 by transmitting gas from the first opening to one or more pressure sensors using the first sensor tube and measuring the first pressure within the first sensor tube. Operation 364 continues by transmitting gas from the second opening to one or more pressure sensors using the second sensor tube and measuring the second pressure within the second sensor tube. Method 360 ends at operation 365 by outputting pressure readings based at least in part on the first pressure and the second pressure measured by one or more pressure sensors. In some embodiments, method 360 does not end at 365 and one or more additional calculations may be performed based on the pressure readings obtained. Although not shown in Figure 3I, in some embodiments, other sensors may be coupled to the first and second sensor tubes to obtain other airflow characteristics such as temperature.

In some embodiments, method 360 further includes calculating the flow rate based on the first pressure, the second pressure, and the predetermined value of the density of the gas. In some embodiments, one or more operations of method 360 may be skipped, rearranged, or omitted. Although the examples here are primarily for exhaust monitoring, this does not exclude the use of online airflow monitoring systems or exhaust monitoring equipment for use in other applications.

FIG. 4A shows a simplified cross-sectional view of an online gas monitoring device 400 including the exhaust gas monitoring device 101 and a damper 402 coupled to a tube 302 . For clarity, the sensor tube and pressure sensor are removed. As shown, damper 402 may be implemented to control the total volume and flow rate of gas 408 within tube 302. In some embodiments, damper 402 includes a rotor 404 and blades 406 coupled to rotor 404 . As shown, the rotor 404 extends along the centerline of the blades 406 (in the x-direction) and along the diameter of the tube 302 . In certain embodiments, rotor 404 may extend parallel to collector element 102 or 104. In some embodiments, the rotor 404 can perform a complete 360 degree rotation (expressed by angle θ) about the axis of the blades 406 . The 360 degree rotation allows for fine control of airflow through tube 302. In certain embodiments, the rotor 404 and blades 406 have a thickness _TB that is less than the lateral thickness T ₄ of either collector element 104 or 120 . Therefore, when the surface 406A of the blade 406 is oriented parallel to the inner wall 302A of the tube 302, the damper will have little effect on the airflow within the tube 302. In certain embodiments, vanes 406 may have a circular planar surface area (orthogonal to the longitudinal or z-axis of tube 302 in the drawings) to effectively provide damping. In some such embodiments, the rotor 404 may extend along the diameter of the tube 302 but must be parallel to the collector element 120 or 104. When blade 406 is circular, blade 406 may have a diameter D _RO that is less than the diameter _DT of tube 302 . In some embodiments, _DRO is between 5% and 25% smaller than _DT . In other embodiments, D _RO is substantially equal to _DT for maximum damping. In some embodiments, the damper 402 is a fan that rotates along the Y-axis and controls the airflow within the duct 302 along the Z-axis.

In certain embodiments, the damper 402 is vertically separated from the collector element 120 by a separation distance S _DC . In the illustrative embodiment, S _DC represents the distance between rotor 404 and collector element 120 . The separation S _DC provides a safe operating distance where the damper does not come into contact with the exhaust gas monitoring device 101 . The separation is at least greater than half the diameter D _RO . In certain embodiments, S _DC is between 3 cm and 30 cm.

In some embodiments, the damper 402 is controlled by a controller external to the online gas monitoring device 400 . In some embodiments, the damper 402 may be controlled by the circuit board 112 of the exhaust gas monitoring device 101 .

As illustrated in Figure 4B, damper 402 may be implemented within substrate processing system 410. In certain embodiments, substrate processing system 410 includes one or more components of substrate processing system 100 (shown in FIG. 1A ). In the illustrative embodiment, exhaust lines 107A-107F each include a damper, such as, for example, dampers 402A, 402B, 402C, 402D, 402E, and 402F (402A-402F). In an embodiment, the pressure is monitored within each of the exhaust lines 107A-107F by an exhaust monitoring device 101 within each respective exhaust line 107A-107F. The flow rate of the gas in the exhaust lines 107A~107F can be calculated by the method outlined above. Flow rate can be calculated dynamically from dynamic measurements of pressure. The flow rates in each exhaust line 107A~107F can be compared with each other. If desired, the flow rate in one or more of the exhaust lines 107A-107F can be changed by rotating the respective dampers 402A-402F. For example, rotation of respective dampers 402A-402F may increase or decrease the gas flow rate within respective exhaust lines 107A-107F. In some embodiments, airflow may be increased or decreased to a maximum or minimum level determined by the rotation angle of the respective exhaust fans and dampers coupled to exhaust lines 107A-107F. In this manner, any damper 402A-402F can be dynamically adjusted to a desired set point within each exhaust line 107A-107F.

Although embodiments of the present disclosure are described in the context of gas monitoring in exhaust ducts, applications of the exhaust gas monitoring devices described in this disclosure are not limited to such uses. In certain embodiments, one or more embodiments of the exhaust monitoring device may be used with other gas flow ducts or tubes within semiconductor manufacturing equipment. In certain embodiments, one or more embodiments of the exhaust monitoring device may be used in other gas flow ducts throughout the manufacturing plant. In some embodiments, the exhaust monitoring equipment is lightweight and configured to communicate with other monitoring devices within the manufacturing plant.

FIG. 5 illustrates a block diagram of a controller system 500 on a circuit board 112 in accordance with certain embodiments of the present disclosure. The controller system 500 includes an input controller 501, a power block 502, a microcontroller block 503, a sensor block 504, and an output controller 505. The circuit board 112 illustrated in FIG. 1B may include an input controller 501 and an output controller 505. In some embodiments, input controller 501 includes an interface for receiving input signals. Input signals can be received through any suitable interface such as Universal Bus (USB) compatible interface, I2C, Thunderbolt, serial interface, parallel interface, etc. In some embodiments, input controller 501 instructs power block 502 to provide specific amounts of power to blocks of controller system 500 . In other embodiments, input controller 501 may be used to download one or more programs to microcontroller block 503 . In some embodiments, microcontroller block 503 includes or is coupled to wireless circuitry (not shown). The wireless circuit may allow the microcontroller block 503 to communicate with other devices such as a server, another wireless device, etc. In this way, pressure readings and/or calculations can be extracted wirelessly from the microcontroller block 503. In some embodiments, pressure sensors 114 and 128 may be calibrated by microcontroller block 503 . According to some embodiments, instructions for calibrating pressure sensors 114, and 128 may be retrieved wirelessly or via a wired device.

In some embodiments, power block 502 includes a DC-DC converter, a linear converter (eg, a low dropout regulator), or any other suitable voltage regulator. In some embodiments, the power block 502 can provide different power levels to different blocks according to their specifications. In some embodiments, the power block includes a rechargeable battery or backup battery to operate the controller system 500 in the absence of input power. In some embodiments, microcontroller block 503 includes any suitable processor and/or associated components to process readings using sensor block 504 .

In some embodiments, microcontroller block 503 includes the processor system described with reference to FIG. 6 . Referring to Figure 5, in some embodiments, sensor block 504 includes one or more sensors. In some embodiments, the one or more sensors include absolute pressure sensors and/or differential pressure sensors. In some embodiments, the one or more sensors include a temperature sensor. Readings from one or more sensors are provided to microcontroller block 503 for processing. The readings are then transmitted to another device via output controller 505. In other embodiments, the microcontroller block 503 may be programmed to perform measurements such as comparing pressure readings from different pressure sensors (such as pressure sensors 114 and 128 in Figure 3E) and calculating flow rates. The microcontroller block 503 can then transmit the flow rate information to the output controller 505 . In some embodiments, microcontroller block 503 is configured to adjust the sensitivity of one or more sensors. In some embodiments, output controller 505 includes wired and/or wireless means to communicate with external devices. In some embodiments, various components of controller system 500 may be recharacterized in one or more blocks.

According to certain embodiments, FIG. 6 illustrates a processor system 600 having a machine-readable storage medium having a machine-readable storage medium that when executed causes a microcontroller in a circuit board of the exhaust monitoring device 101 (eg, FIG. Microcontroller block 503 in 5) provides instructions for measuring and reporting gas properties. The processes described in various embodiments of the present disclosure may be stored on a machine-readable medium (eg, 603) as computer-executable instructions. In some embodiments, processor system 600 includes memory 601, processor 602, machine-readable storage media 603 (also referred to as tangible machine-readable media), communication interface 604 ( For example, wireless or wired interface), and network bus 605. In some embodiments, various components of system 600 may be components of microcontroller block 503 .

In some embodiments, processor 602 is a digital signal processor (DSP), an application specific integrated circuit (ASIC), a general purpose central processing unit (CPU), or a device that implements a simple finite state machine to perform many of the processes described herein. Low power logic.

In some embodiments, the logic blocks of processor system 600 are coupled together via network bus 605 . Network bus 605 may be implemented using any suitable communications protocol. In certain embodiments, the machine-readable storage medium 603 includes instructions (also referred to as program software code/instructions) for measuring gas pressure and gas flow and/or controlling dampers within the measurement apparatus as described above with reference to various embodiments. ).

In one example, machine-readable storage medium 603 is a machine-readable storage medium (hereinafter referred to as machine-readable medium 603 ) having instructions for measuring gas pressure and gas flow and for reporting the measured gas pressure. The machine-readable medium 603 has machine-readable instructions that, when executed, cause the processor 602 to perform measurement and/or reporting methods as discussed with reference to various embodiments.

Programming software code/instructions associated with various embodiments may be implemented as a portion of an operating system or a particular application, a component, a program, an object, a module, a subroutine, or other sequence of instructions or an organization of a sequence of instructions. is "programming code/instructions", "operating system software code/instructions", "application software code/instructions", or simply "software", or is implemented as firmware embedded in a processor. In some embodiments, software code/instructions associated with processes of various embodiments are executed by processor system 600.

In some embodiments, machine-readable storage medium 603 is computer-executable storage medium 603. In some such embodiments, software code/instructions associated with various embodiments are stored in computer-executable storage media 603 and executed by processor 602. Here, computer-executable storage media 603 may be used to store tangible machine-readable program software code/instructions and data that, when executed by a computing device, cause one or more processors (eg, processor 602) to perform processes. Media603.

Tangible machine-readable medium 603 may include storage of executable software code/instructions and data in a number of tangible locations, including, for example, ROM, volatile RAM, non-volatile memory and/or cache and/or as in Other tangible memories referenced in this application. Portions of this software code/instructions and/or data may be stored in any of these storage and memory devices. In some embodiments, the software code/instructions may be retrieved from other storage, including, for example, via a centralized server or a peer-to-peer network or the like, including the Internet. Different portions of the software code/instructions and data may be obtained at different times and in different communication sessions or within the same communication session.

Software code/instructions associated with various embodiments may be retrieved in their entirety prior to execution of the respective software program or application. Alternatively, portions of the software code/instructions and data may be retrieved dynamically (eg, in real time) when required for execution. Alternatively, by way of example, some combination of these ways of obtaining software code/instructions and data may be generated, e.g., for different applications, components, programs, objects, modules, subroutines, or other instructions. The organization of a sequence or sequence of instructions. Accordingly, there is no requirement that the data and instructions be entirely on tangible machine-readable medium 603 at the time of a particular instance.

Examples of tangible machine-readable media 603 include, but are not limited to, recordable and non-recordable forms of media, such as volatile and non-volatile memory devices, read only memory (ROM), random access memory (RAM), flash memory, etc. Flash memory devices, floppy disks and other removable disks, magnetic storage media, optical storage media (e.g., compact disc read-only memories (CD ROMS), digital versatile discs (DVDs), etc.), and others. The software program code/instructions can be temporarily stored in a digital tangible communication link and at the same time, electrical, optical, acoustic, or other forms of propagation signals, such as carrier waves, infrared signals, digital signals, etc., can be implemented through such tangible communication links.

In addition to what is described herein, many modifications may be made to the embodiments and implementations disclosed herein without departing from the scope of what is described herein. Accordingly, the descriptions of the embodiments herein should be construed as examples only and not as limiting the scope of the present disclosure. The scope of the invention should be gauged only by reference to the following claims.

100, 410: Substrate processing system 101, 200: Exhaust monitoring equipment 102: Perimeter support frame 103: Exhaust system 104, 120: Collector element 104A: Top surface 104B: Bottom surface 104C, 104D: Side wall surface 105: Processing tool 105A: Processing chamber 105B: Transfer chamber 105C: Equipment front-end module 105D: Air box 106, 106A, 106B, 106C, 108, 108A, 108B, 108C, 122, 122A, 124, 124A: Opening 107A, 107B, 107C, 107D, 107E, 107F: Exhaust pipeline 109: Exhaust reservoir 110A, 110B, 110C, 110D, 110E: Sensor tube 111: External controller 112: Circuit board 114, 128: Pressure sensor 114A: The first nozzle of the pressure sensor 114 114B: Pressure sensor The second nozzle 116 of the detector 114: ring structure _DR , D ₁ , D ₂ , D _T , D _RO : diameter T ₁ , T ₂ , T ₃ , T ₄ , T _B : thickness S ₁ , S ₂ , S ₃ , S _DC : distance Nozzle 128B of device 128: second nozzle 130 of pressure sensor 128: support plate 130A, 130B: extension 132: rotating plate 134: opening 136: opening 202: resin 300: tube structure 302: cylindrical tube 302A: inner wall 304 : Mounting frame 306: Bolt hole 307: Opening 308: End 309: Bolt 320, 330, 350: Equipment D _I , D _T : Inner diameter A _T : Cross-sectional area A _CE : Area A _SP : Effective surface area 340: Method 341, 342, 343: Operation 351: Gas 352: One end of opening 122A 353: The opposite end of opening 122A 354: One end of opening 106A 355: The opposite end of opening 106A 356, 357: The end of opening 124A 360: Method 361, 362, 363, 364, 365: Operation 400: Online gas monitoring equipment 402, 402A, 402B, 402C , 402D, 402E, 402F: Damper 404: Rotor 406: Blade 408: Gas θ: Angle 500: Controller system 501: Input controller 502: Power block 503: Microcontroller block 504: Sensor block 505: Output Controller 600: Processor system 601: Memory 602: Processor 603: Machine-readable storage medium 604: Communication interface 605: Network bus

In the accompanying drawings, the material described herein is illustrated by way of example and not by way of limitation. For the sake of simplicity and clarity, the elements depicted in the drawings are not necessarily drawn to scale. For example, the dimensions of some elements may be exaggerated relative to other elements for clarity. Also, while many physical features may be represented in simplified "ideal" forms and geometries for clarity of discussion, it is understood that actual implementations may only approximate the ideals depicted. For example, smooth surfaces and square intersections can be drawn while ignoring the finite roughness, rounded corners, and imperfect angular intersection characteristics of structures formed by nanofabrication techniques. Furthermore, where deemed appropriate, reference numbers are repeated in the drawings to indicate corresponding or similar elements.

FIG. 1A illustrates a schematic diagram of a substrate processing system in which a plurality of exhaust lines are coupled to an exhaust or factory vacuum system, according to an embodiment of the present disclosure.

Figure IB is a drawing of an isometric view of a device designed to measure gas properties, in accordance with an embodiment of the present disclosure.

Figure 1C is a drawing of an isometric view of a support frame used in the device of Figure IB, in accordance with an embodiment of the present disclosure.

FIG. 1D is a drawing of a portion of a collector element of the support frame illustrated in FIG. 1C , in accordance with an embodiment of the present disclosure.

FIG. 1E is a drawing of a portion of a collector element of the support frame illustrated in FIG. 1C , in accordance with an embodiment of the present disclosure.

FIG. 1F is an enlarged isometric view of a portion of the device of FIG. 1A , in accordance with an embodiment of the present disclosure.

Figure 1G is an enlarged isometric view of a portion of the device of Figure 1A, in accordance with an embodiment of the present disclosure.

FIG. 2A is a drawing of the device of FIG. 1A illustrating the mechanical coupling between a circuit board and a support frame of the device, in accordance with an embodiment of the present disclosure.

According to an embodiment of the present disclosure, FIG. 2B is a drawing of the circuit board of FIG. 2A , wherein the circuit board is wrapped in a protective casing.

Figure 3A is a drawing of a tube in accordance with an embodiment of the present disclosure.

Figure 3B is a drawing of the device of Figure 1B coupled within the tube depicted in Figure 3A, in accordance with an embodiment of the present disclosure.

According to an embodiment of the present disclosure, FIG. 3C is a plan view of the structure of FIG. 3B.

FIG. 3D is a flowchart illustrating a method of measuring gas pressure in the device of FIG. 3B , according to an embodiment of the present disclosure.

Figure 3E is a plot of pressure measurements using the device of Figure 3B, in accordance with an embodiment of the present disclosure.

Figure 3F is a plot of pressure measurements using the device of Figure 3B, in accordance with an embodiment of the present disclosure.

Figure 3G is a plot of pressure measurements using the device of Figure 3B, in accordance with an embodiment of the present disclosure.

Figure 3H is a plot of pressure measurements using the device of Figure 3B, in accordance with an embodiment of the present disclosure.

According to an embodiment of the present disclosure, FIG. 3I is a flowchart illustrating a method of measuring gas pressure in the device of FIG. 3B.

According to an embodiment of the present disclosure, FIG. 4A shows a simplified schematic diagram of the structure of FIG. 3B including a damper.

FIG. 4B illustrates a schematic diagram of a substrate processing system in which each exhaust line of a plurality of exhaust lines includes a damper, in accordance with an embodiment of the present disclosure.

Figure 5 illustrates a block diagram of a collector system, in accordance with an embodiment of the present disclosure.

In accordance with various embodiments, FIG. 6 illustrates a processor system having a machine-readable storage medium having instructions that, when executed, cause the processor to measure and report gas properties.

101: Exhaust monitoring equipment

102:Peripheral support frame

104,120: Collector element

106:Open your mouth

108:Open your mouth

110A, 110B: Sensor tube

112:Circuit board

114: Pressure sensor

125,127: Part of exhaust monitoring equipment 101

126:Transmitter

130:Support plate

Claims (28)

An airflow monitoring system consisting of: one tube; A perimeter support frame coupled within the tube, wherein the perimeter support frame includes one or more collector elements extending laterally across the perimeter support frame, wherein the one or more collector elements include a collector element configured to draw in gas plural openings; and A circuit board coupled to the peripheral support frame in the tube, the circuit board including: one or more pressure sensors coupled to the one or more collector elements; and A transmitter circuit for transmitting readings from the one or more pressure sensors. The air flow monitoring system of claim 1, wherein the tube includes a circular cross-section. The airflow monitoring system of claim 1, wherein the one or more collector elements comprise a collector element, wherein the collector element spans the tube, and wherein one or more openings in the collector element are configured to inhale the exhaust gas flowing in the tube. The airflow monitoring system of claim 1, wherein an individual pressure sensor of the one or more pressure sensors includes one or more nozzles. The air flow monitoring system of claim 1, wherein at least one pressure sensor is an absolute pressure sensor. The air flow monitoring system of claim 1, wherein at least one pressure sensor is a differential pressure sensor. The airflow monitoring system of claim 1, wherein the one or more collector elements include a first plurality of openings along a first direction parallel to a longitudinal axis of the tube, and a second plurality of openings along the first direction. Open your mouth. The airflow monitoring system of claim 7, further comprising one or more sensors coupled between respective openings in the one or more collector elements and respective nozzles of the one or more pressure sensors Organ tube. The airflow monitoring system of claim 1, wherein the one or more collector components include: a first collector element along a first position of the peripheral support frame; and A second collector element is spaced apart from the first collector element, wherein the first collector element and the second collector element are spaced apart along a longitudinal axis of the tube. The air flow monitoring system of claim 9, wherein a separation distance between the first collector element and the second collector element is between 5 cm and 100 cm. The airflow monitoring system of claim 9, wherein the first collector element and the second collector element include: a first plurality of openings along a second direction parallel to the longitudinal axis of the tube; and A second plurality of openings along a third direction orthogonal to a longitudinal axis of the tube. For example, the airflow monitoring system of claim 11 further includes: A first plurality of sensor tubes, wherein individual sensor tubes of the first plurality of sensor tubes are coupled between respective openings in the first collector element and the one or more pressure sensors. between individual nozzles; and A second plurality of sensor tubes, wherein individual sensor tubes of the second plurality of sensor tubes are coupled to respective openings in the second collector element and to the first plurality of sensor tubes. The remaining one or more pressure sensors are coupled between respective nozzles. The airflow monitoring system of claim 1, wherein the tube further includes an opening adjacent the peripheral support frame, the opening being configured to measure the pressure within the tube relative to a pressure outside the tube. If the airflow monitoring system of claim 1 further includes a damper in the tube, wherein the damper is longitudinally away from the one or more collector elements, the damper includes: a plate having a cross-sectional area smaller than the cross-sectional area of an opening of the tube; and A motor is coupled to the plate, the motor being configured to provide rotation of the plate about a line orthogonal to a longitudinal axis. The airflow monitoring system of claim 1, wherein the circuit board is coupled to a peripheral portion of the peripheral support frame. An exhaust monitoring device including: a perimeter support frame including one or more collector elements extending laterally across the perimeter support frame, wherein the one or more collector elements include a plurality of openings configured to draw in gas; and A circuit board coupled to the peripheral support frame, the circuit board includes: a plurality of pressure sensors coupled to the one or more collector elements; and A transmitter circuit for transmitting readings from the plurality of pressure sensors. The exhaust monitoring device of claim 16, wherein the peripheral support frame includes a circular ring structure, and wherein the one or more collector elements include a collector element extending across a diameter of the circular ring structure. The exhaust monitoring device of claim 17, wherein the peripheral support frame further includes a pair of vertical support columns on opposite ends of the diameter of the circular ring structure, the pair of vertical support columns extending away from the circular ring structure , wherein the collector element is a first collector element, and the one or more collector elements further comprise a second collector element, wherein the second collector element is connected to each of the pair of vertical support columns. or coupled. The exhaust gas monitoring device of claim 18, wherein the first collector element is directly above the second collector element and parallel to the second collector element. The exhaust gas monitoring device of claim 19, wherein the first collector element includes one or more first openings and the second collector element includes one or more second openings. The exhaust gas monitoring device of claim 20, wherein individual ones of the first collector element and the second collector element include a first plurality of openings along a direction parallel to a longitudinal axis of a peripheral support structure , and a second plurality of openings along a direction orthogonal to the longitudinal axis of the peripheral support frame. The exhaust monitoring device of claim 17, wherein the circuit board is coupled to the circular ring structure. A method for utilizing an exhaust monitoring device to determine the properties of one or more air flows in an exhaust duct, the method comprising: Inhaling a gas through a first opening in a first collector element and a second opening in a second collector element of the exhaust gas monitoring device, wherein the first collector element and the second collector element tied at a distance within the exhaust duct; The gas is transported from both the first opening and the second opening to one or more pressure sensors located in the exhaust duct, wherein a first sensor tube is used to transport the gas from the first opening to the one or more pressure sensors, and using a second sensor tube to deliver the gas from the second opening to the one or more pressure sensors; measuring a first pressure within the first sensor tube by the one or more pressure sensors; measuring a second pressure within the second sensor tube by the one or more pressure sensors; and A pressure reading is output based at least in part on the first pressure and the second pressure measured by the one or more pressure sensors. The method of claim 23 for using the exhaust monitoring device to determine one or more gas flow properties in the exhaust pipeline further includes a predetermined value based on the first pressure, the second pressure, and a density of the gas. value to calculate the flow rate. As claimed in claim 23, the method for using the exhaust monitoring device to determine one or more air flow properties in the exhaust duct, wherein the first opening is a first plurality of openings, and wherein the second opening is a second plurality of openings, The step of inhaling the gas further includes inhaling the gas through the first plurality of openings and the second plurality of openings. The method of claim 23 for using the exhaust gas monitoring device to determine one or more air flow properties in the exhaust duct, wherein the first sensor pipe is connected to a first center of the first collector element is coupled to an opening at a second center of the second collector element, wherein the second sensor tube is coupled to an opening at a second center of the second collector element, wherein the first center and the second center are coupled along a line parallel to A direction of a longitudinal axis of the exhaust gas monitoring device is separated, and the step of measuring the first pressure and the second pressure includes measuring along the longitudinal axis. The method of claim 23 for using the exhaust gas monitoring device to determine one or more air flow properties in the exhaust duct, wherein the first collector element is measured at a first position other than the center of the first collector element. a pressure, wherein the second pressure is measured at a second position other than the center of the second collector element, and wherein a direction between the first position and the second position is parallel to the exhaust A vertical axis of the monitoring device. The method of claim 25 for using the exhaust gas monitoring device to determine one or more airflow properties in the exhaust duct, wherein the first plurality of openings are along a first diameter of the exhaust gas monitoring device, wherein the The second plurality of openings is along a second diameter of the exhaust gas monitoring device, wherein the method further includes measuring pressure simultaneously along the first plurality of openings and along the second plurality of openings.

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