Chemical concentration measurement and control of semiconductor fabrication equipment

Abstract

Techniques for chemical concentration measurement and control of semiconductor fabrication equipment are disclosed. During an operation of the semiconductor fabrication equipment, outputs of a sensing arrangement coupled with the semiconductor fabrication equipment are monitored. The sensing arrangement includes at least one micro-electromechanical system (MEMS) sensor configured to output signals indicative of a chemical concentration in at least one stage of the semiconductor fabrication equipment. Based on the monitored outputs, a parameter of the operation is controlled.

Description

CHEMICAL CONCENTRATION MEASUREMENT AND CONTROL OF SEMICONDUCTOR FABRICATION EQUIPMENTINCORPORATION BY REFERENCE

[0001] A PCT Request Form is filed concurrently with this specification as part of the present application. Each application that the present application claims benefit of or priority to as identified in the concurrently filed PCT Request Form is incorporated by reference herein in their entireties and for all purposes.BACKGROUND

[0002] Semiconductor fabrication systems use a wide variety of gaseous chemicals for product fabrications and equipment cleaning. Real time knowledge of the composition, flow rates and densities of those gases can be important for process optimization and to minimize use of environmentally harmful chemicals. However, obtaining accurate realtime knowledge can be difficult or expensive.

[0003] The background description provided herein is for the purposes of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor implicitly admitted as prior art against the present disclosure.SUMMARY

[0004] Techniques for chemical concentration measurement and control of semiconductor fabrication equipment are disclosed.

[0005] According to some implementations, a method of chemical concentration measurement and control of semiconductor fabrication equipment includes monitoring, during an operation of the semiconductor fabrication equipment, outputs of a sensing arrangement coupled with the semiconductor fabrication equipment. The sensing arrangement includes at least one micro-electromechanical system (MEMS) sensor configured to output signals indicative of a chemical concentration in at least one stage of the semiconductor fabrication equipment. Based on the monitored outputs a parameter of the operation is controlled.

[0006] In some examples, the method may include, based on the monitored outputs, one or more of: taking a corrective action, sounding an alarm, signaling an operator, initiating a soft shutdown of the fabrication equipment, aborting an operation of the fabrication equipment, or recommending further analysis and / or other corrective actions.In some examples, the corrective action includes one or more of changing gas flow, pressure, temperature, and / or RF power.

[0007] In some examples, the MEMS sensor may include a field effect transistor with a sensing channel comprising a two-dimensional (2D) nanomaterial. In some examples, the 2D nanomaterial may include a graphene, a transition metal dichalcogenide (TMD) and / or black phosphorous. In some examples, the 2D nanomaterial may include nanoparticles of tin oxide (SNO2), tungsten trioxide (WO3), silver or platinum, or a combination thereof.

[0008] In some examples, the MEMS sensor may include a cantilever-based mass / vibration sensing device.

[0009] In some examples, monitoring the outputs may include processing, with a controller, the outputted signals to determine a chemical concentration measurement in the at least one stage of the semiconductor fabrication equipment. In some examples, controlling the parameter may include the controller making a comparison between the determined chemical concentration and a desired chemical concentration and controlling the parameter responsive to the comparison.

[0010] In some examples, the method may include repeating the monitoring outputs and the controlling the parameter, continuously, or at intervals, as a closed loop control process.

[0011] In some examples, the sensing arrangement may include a plurality of MEMS sensors, each of the MEMS sensors being configured to output respective signals indicative of a chemical concentration of a respective chemical species in the at least one stage of the semiconductor fabrication equipment. In some examples, the at least one stage may include a process station, and the operation may include a deposition process performed within the process station; the semiconductor fabrication equipment may include a source of a carrier gas and one or more sources of process gases for performing the deposition process; the sensing arrangement may be configured to detect a concentration of at least one of the process gases; and controlling the parameter of the operation may include maintaining or adjusting a pressure and / or flow rate of the carrier gas and / or the process gas. In some examples, at least one of the process gases may include tungsten hexaflouride (WF6), a chloride of tungsten, an oxychloride of molybdenum, tetraethoxysilane (TEOS), silane (SiH4), diborane (B2H6), ammonia (NH3), ammonium (NH4), or nitrogen trifluoride (NF3), methane (CH4), and / or carbon monoxide (CO). In some examples, the plurality of MEMS sensors may include at leastone MEMS sensor located at an inlet of the process station and at least one MEMS sensor located at an outlet of the process station. In some examples, at least one MEMS sensor may be located within the process station. In some examples, the method may include controlling radio frequency (RF) generator settings and / or actuating flow and / or pressure control mechanisms, responsive to the outputted respective signals so as to obtain a desired chemical concentration of at least one of the process gases within the process station, at the inlet of the process station and / or at the outlet of the process station. In some examples, the operation may include a purging process, performed after the deposition process, the purging process configured to remove at least the process gases from the process station. The method may further include determining, from the outputted respective signals, whether or not the process gases have been sufficiently removed.

[0012] In some examples, the semiconductor fabrication equipment may include multiple stations for performing a deposition process, each respective station comprising a sensing arrangement configured to detect a concentration of at least one of the process gases for the respective station. Controlling the parameter may include controlling radio frequency (RF) generator settings and / or maintaining or adjusting a pressure and / or flow rate of the carrier gas and / or the process gas at each respective station. In some examples, the operation may include cleaning the process station and the outputted respective signals are indicative of a chemical concentration of cleaning compounds or byproducts thereof. In some examples, the cleaning compounds or byproducts may include nitrogen trifluoride (NF3), atomic fluorine (F), molecular fluorine (F2) and / or hydrogen fluoride (HF). In some examples, the operation may include cleaning the process station with a remote plasma clean system and the outputted respective signals are indicative of a cleaning efficiency and / or health of the remote plasma clean system. In some examples, controlling the parameter of the operation may include determining, from the outputted respective signals whether or not the process station is safe to open. In some examples, at least one of the one or more sources of process gases may include an ampoule configured to produce the process gas from a solid or liquid precursor chemical contained in the ampoule, and the sensing arrangement may include at least one micro-electromechanical system (MEMS) sensor disposed proximal to an ampoule outlet and configured to measure chemical concentrations of the process gas proximal to the ampoule outlet. In some examples, the respective chemical species in the at least one stage of the semiconductor fabrication equipment may include oxygen, and monitoring the outputs of the sensingarrangement may include determining whether an indicated concentration of oxygen represents a corrosion risk.

[0013] According to some implementations, an apparatus for monitoring semiconductor fabrication equipment includes a sensing arrangement coupled with the semiconductor fabrication equipment, the sensing arrangement including at least one micro-electromechanical system (MEMS) sensor configured to output signals indicative of a chemical concentration in at least one stage of the semiconductor fabrication equipment during an operation of the semiconductor fabrication. The sensing arrangement is communicatively coupled with a controller, the controller being configured to monitor outputs of the sensing arrangement and comprising logic configured to control, based on the monitored outputs, an operational parameter of the semiconductor fabrication equipment.

[0014] In some examples, the logic may be further configured to control, based on the monitored outputs, a corrective action, one or more of: sounding an alarm, signaling an operator, initiating a soft shutdown of the fabrication equipment, aborting an operation of the fabrication equipment, or recommending further analysis and / or other corrective action. In some examples, the corrective action may include one or more of changing gas flow, pressure, temperature, and / or RF power.

[0015] In some examples, the MEMS sensor may include a field effect transistor with a sensing channel comprising a two-dimensional (2D) nanomaterial. In some examples, the 2D nanomaterial may include graphene, a transition metal dichalcogenide (TMD) and / or black phosphorous. In some examples, the 2D nanomaterial may include nanoparticles of tin oxide (SNO2), tungsten trioxide (WO3), silver or platinum, or a combination thereof.

[0016] In some examples, the MEMS sensor may include a cantilever-based mass / vibration sensing device.

[0017] In some examples, the controller may be configured to process the outputted signals to determine a chemical concentration measurement in the at least one stage of the semiconductor fabrication equipment.

[0018] In some examples, the sensing arrangement may include a plurality of MEMS sensors, each of the MEMS sensors being configured to output signals indicative of a chemical concentration of a respective chemical species in the at least one stage of the semiconductor fabrication equipment. In some examples, the at least one stage may include a process station, and the operation may include a deposition process performedwithin the process station; the semiconductor fabrication equipment may include a carrier gas source and one or more sources of process gases for performing the deposition process; the sensing arrangement may be configured to detect a concentration of at least one of the process gases; and the controlling the parameter of the operation may include maintaining or adjusting a pressure and / or flow rate of the carrier gas and / or the process gas.

[0019] In some examples, at least one of the process gases may include tungsten hexaflouride (WF6), a chloride of tungsten, an oxychloride of molybdenum, tetraethoxysilane (TEOS), silane (SiH4), diborane (B2H6), ammonia (NH3), ammonium (NH4), or nitrogen trifluoride (NF3), methane (CH4), and / or carbon monoxide (CO). In some examples, the plurality of MEMS sensors may include at least one MEMS sensor located at an inlet of the process station, and at least one MEMS sensor located at an outlet of the process station. In some examples, the plurality of MEMS sensors may include at least one MEMS sensor located within the process station. In some examples, the operation may include a purging process, performed after the deposition process, the purging process configured to remove at least the process gases from the process station and the controller may be configured to determine, from the monitored outputted respective signals, whether or not the process gases have been sufficiently removed. In some examples, the semiconductor fabrication equipment may include multiple stations for performing a deposition process, each respective station comprising a sensing arrangement configured to detect a concentration of at least one of the process gases for the respective station; and controlling the parameter may include maintaining or adjusting a pressure and / or flow rate of the carrier gas and / or the process gas at each respective station. In some examples, the operation includes cleaning the process station and the outputted respective signals are indicative of a chemical concentration of cleaning compounds or byproducts thereof. In some examples, the cleaning compounds or byproducts may include nitrogen trifluoride (NF3) and / or hydrogen fluoride (HF). In some examples, the controlling the parameter of the operation may include determining, from the outputted respective signals whether or not the process station is safe to open. In some examples, at least one of the one or more sources of process gases may include an ampoule configured to produce the process gas from a solid or liquid precursor chemical contained in the ampoule, and the sensing arrangement may include at least one microelectromechanical system (MEMS) sensor disposed proximal to an ampoule outlet andconfigured to measure chemical concentrations of the process gas proximal to the ampoule outlet.

[0020] In some examples, the sensing arrangement may be configured to output signals indicative of a chemical concentration of one or more of water, hydrogen, oxygen, tungsten hexaflouride (WF6), a chloride of tungsten, an oxychloride of molybdenum, tetraethoxysilane (TEOS), silane (SiH4), diborane (B2H6), ammonia (NH3), ammonium (NH4), or nitrogen trifluoride (NF3), methane (CH4), and / or carbon monoxide (CO), nitrogen trifluoride (NF3) and / or hydrogen fluoride (HF).BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic diagram of semiconductor fabrication equipment.

[0022] Figure 2 is a schematic diagram of a multi-station a multi-station semiconductor fabrication tool.

[0023] Figure 3 illustrates a simplified schematic of equipment for semiconductor fabrication, according to some implementations.

[0024] Figure 4 presents a flowchart of an example process for measuring and controlling chemical concentration measurement in a semiconductor fabrication system, according to some implementations.

[0025] Figure 5 illustrates process stations of a process chamber fluidically coupled with a gas delivery arrangement by way of a control valve arrangement, according to some implementations.

[0026] Figure 6 illustrates a gas delivery arrangement including an ampoule, partially filled with a precursor, according to some implementations.DETAILED DESCRIPTION

[0027] In the following description, numerous specific details are set forth to provide a thorough understanding of the presented embodiments. The disclosed embodiments may be practiced without some or all these specific details. In other instances, well-known process operations have not been described in detail to not unnecessarily obscure the disclosed embodiments. While the disclosed embodiments will be described in conjunction with the specific embodiments, it will be understood that it is not intended to limit the disclosed embodiments.

[0028] Figure 1 shows a highly simplified schematic of semiconductor fabrication equipment with which the presently disclosed techniques may be implemented. The system 100 may be configured for depositing films on or over a semiconductor substrate utilizing any number of processes. For example, the system 100 may be adapted forperforming chemical vapor deposition (CVD), plasma-enhanced CVD (PECVD), atomic layer deposition (ALD) and / or atomic layer epitaxy (ALE).

[0029] In the illustrated example, the system 100 includes a single process station 102 comprising a process chamber enclosing, in an interior volume, a single substrate holder 108 (that may be referred to hereinbelow as a pedestal) and a substrate 112, disposed on the pedestal 108. The interior volume may be maintained under vacuum by a vacuum pump 118. A gas distributor 106 (that may be referred to hereinbelow as a s showerhead) is fluidically coupled with a gas delivery arrangement 101 and may be configured to permit delivery of film precursors, for example, as well as carrier and / or purge and / or process gases, secondary reactants, and / or cleaning agents, for example.

[0030] The showerhead 106 may operate to distribute process gases and / or reactants (e.g., film precursors) toward the substrate 112, the flow of which may be controlled by one or more valves upstream from the showerhead (not illustrated). In the implementation depicted in Figure 1, the substrate 112 is depicted as located beneath showerhead 106 and is shown disposed on the pedestal 108. The showerhead 106 may include any suitable shape and may include any suitable number and arrangement of ports for distributing process gases to the substrate 112. In some implementations involving two or more stations, the gas delivery arrangement 101 may include valves or other flow control structures upstream from the showerhead, which can independently control the flow of process gases and / or reactants to each station so as to permit gas flow to one station while preventing gas flow to one or more other stations. Moreover, the gas delivery arrangement 101 may be configured to independently control process gases and / or reactants delivered to each station in a multi-station apparatus such that the gas composition provided to different stations is different; e.g., the partial pressure of a gas component may vary between stations at the same time.

[0031] In the implementation of Figure 1, gas volume 107 is depicted as being located beneath showerhead 106. In some implementations, the pedestal 108 may be raised or lowered to expose the substrate 112 to gas volume 107 and / or to vary the size of the gas volume 107. A separation distance between the pedestal 108 and the showerhead 106 may be referred to as a “gap.” In some implementations, the pedestal 108 may be lowered and / or raised during portions of a deposition process to modulate process pressure, reactant concentration, etc., within the gas volume 107.

[0032] In the illustrated example, the showerhead 106 and the pedestal 108 are electrically coupled to a radio frequency (RF) signal generator 114 and a matchingnetwork 116 for coupling power to a plasma generator. For example, the showerhead 106 may function as an electrode for coupling radio frequency power into the process station 102. The RF signal generator 114 and the matching network 116 may be operated at any suitable RF power level and be configured to form plasma having a desired composition of radical species, ions, and electrons. In addition, RF signal generator 114 may provide RF power having more than one frequency component, such as a low-frequency component (e.g., less than about 2 MHz) as well as a high frequency component (e.g., greater than about 2 MHz). In some implementations, plasma ignition and maintenance conditions are controlled with appropriate hardware and / or appropriate machine-readable instructions in a system controller which may provide control instructions via a sequence of input / output control instructions.

[0033] For clarity of illustration, the processing apparatus 100 is depicted in Figure 1 as a standalone station (102) of a process chamber for maintaining a low-pressure environment. However, some fabrication tools employ a plurality of process stations such as shown in Figure 2, which schematically depicts an implementation of a multi-station fabrication tool 200. The fabrication tool 200 employs a process chamber 214 that includes multiple fabrication process stations, each of which may be used to perform processing operations on a substrate held in a wafer holder (such as, e.g., pedestal 108 of Figure 1). In the implementation of Figure 2, the process chamber 214 is shown as having four process stations numbered from 1 to 4. However, in certain other implementations, multi-station processing apparatuses may have more or fewer process stations depending on the implementation and, for instance, the desired level of parallel wafer processing, size / space constraints, cost constraints, etc. Figure 2 additionally shows substrate handler robot 206, which may operate under the control of system controller 250 and be configured to move wafers from a cassette loaded through a pod 208 into an inbound load lock 202 via an atmospheric port 210. A wafer is placed by the robot 206 on a substrate holder 212 in the inbound load lock 202, the atmospheric port 210 is closed, and the load lock is pumped down. Where the inbound load lock 202 includes a remote plasma source, the wafer may be exposed to a remote plasma treatment in the load lock prior to being introduced into a process chamber 214. Further, the wafer also may be heated in the inbound load lock 202 as well, for example, to remove moisture and adsorbed gases. Next, a chamber transport port 216 to process chamber 214 is opened, and another robot (not shown) places the wafer into the reactor on a substrate holder of a first station shown in the reactor for processing. While the embodiment depicted in FIG. 2 includes load locks, itwill be appreciated that, in some embodiments, direct entry of a wafer into a process station may be provided.

[0034] The system controller 250 may be configured to control process conditions and hardware states of fabrication tool 200. It may interact with one or more sensors, gas flow subsystems, temperature subsystems, and / or plasma subsystems to control process gas flow, thermal conditions, and / or plasma conditions as appropriate for controlling a fabrication process. System controller 250 and the above-mentioned subsystems may act to implement a recipe or other process conditions in the stations of process chamber 214.

[0035] In multi- station fabrication tools, an RF signal generator may be coupled to an RF signal distribution unit, which is configured to divide the power of the input signal into, for example, four output signals. Output signals from an RF signal distribution unit may possess similar levels of RF voltage and RF current, which may be conveyed to individual stations of a multi- station fabrication tool.

[0036] From the foregoing description, it will be appreciated that semiconductor fabrication systems contemplated by the present disclosure may include numerous equipment elements or components, many of which may be configured to control gas or liquid flows of various fluids. Accurate control of the flows of such gas / liquid species is important in various aspects. For example, it can allow optimization of a process “recipe” of precursor gas delivery which can have an impact on on-wafer performance. As a further example, it can allow for optimization of tool cleaning processes and improve life of components. As a yet further example, it can allow better control and / or reduced use of gasses that have a high toxicity or a high greenhouse gas equivalency.

[0037] In the absence of the presently disclosed techniques, techniques for monitoring delivery rates of precursor gases or cleaning fluids include optical methods such as infrared end point detection (IREPD) or through mass spectroscopy using a residual gas analyzer (RGA) or through optical spectroscopy such as optical emission spectroscopy (OES). Such techniques are generally expensive and may accordingly be used sparingly. Alternatives include developing process control sequences that provide timed solutions, but using the same timed solutions across multiple stations and / or modules does not always provide repeatable and similar results, particularly in the context of a high- volume manufacturing facility having numerous stations and / or modules. Accordingly, active sensing and control of fluid flow results in better performance than timed solutions.

[0038] The present inventors have appreciated that chemical concentration measurements in various locations (“stages”) of semiconductor fabrication equipment maybe advantageously performed by micro-electromechanical systems (MEMS) techniques, either in conjunction with or as a field effect transistor (FET) (e.g., a metal-oxide-semiconductor field-effect transistor (MOSFET)) for electrical sensing or a cantilever based (mass / vibration sensing) device configured to detect concentrations of species of interest. Advantageously, such sensors may provide chemical sensing with a response time on the order of milliseconds to seconds (depending on the application) and the sensitivity may be on the order of tens of parts per billion. Because of their small size and low cost, a number of such sensors may be used in a given semiconductor fabrication system, for a variety of purposes. For example, multiple species detection is possible inline where each of two or more sensors is configured to sense a different species.Moreover, sensors may be coupled with the semiconductor fabrication system at multiple stages, for example, upstream and downstream of a plasma processing or deposition chamber. As a result, desired chemical concentrations at multiple locations may be continuously maintained by closed loop, real-time control of operational parameters of the semiconductor fabrication system.

[0039] A FET sensor contemplated by the present disclosure may include a sensing channel disposed between and electrically coupled with a source electrode and a drain electrode. An electrical perturbation introduced by a target analyte binding with a surface of the sensing channel results in modulation of the semiconductor channel current, and such modulation may be correlated with chemical concentration of the targeted analyte(s). As disclosed in Fin, et al., “Gas Detection System and Methods Using Graphene Filed Effect Transistors”, U.S. Pat. Publ. No. 2018 / 0180573 and Mao, et al., “Two-dimensional nanomaterial-based field-effect transistors for chemical and biological sensing”, Chem. Soc. Rev., 2017, 46, 6872, for example, the conductance of the FET channel may change upon adsorption of target molecules onto a sensing channel surface formed from a two-dimensional (2D) nanomaterial such as graphene, a transition metal dichalcogenide (TMD) or black phosphorous. The sensor may be configured to specifically target one or more particular analytes by, for example, depositing appropriate nanoparticles onto the channel sensing surface. For example, nanoparticles of tin oxide (SNO2), tungsten trioxide (WO3), silver or platinum, or various combinations thereof, may be contemplated.

[0040] A controller may be configured to operate the sensing arrangement and analyze outputs of the sensing arrangement so as to obtain chemical concentration measurement data and / or detect changes in concentration measurement data. Moreover, the controller may be configured to compare the data with a desired chemical concentration level. Insome implementations, the desired chemical concentration level may remain constant with time; in other implementations, the desired chemical concentration level may vary with time and the controller may be configured to control, in real-time, operational parameters of the semiconductor fabrication system so as to achieve a desired profile of chemical concentration level as a function of time.

[0041] Figure 3 illustrates a simplified schematic of a system 300 for semiconductor fabrication. Similarly to system 100 (Figure 1), the system 300 includes the gas delivery arrangement 101, the process station 102, the showerhead 106, the pedestal 108 and the vacuum pump 118. The gas delivery arrangement 101 may be configured to selectively permit delivery of film precursors, for example, as well as carrier gases, process gases, purge gases, secondary reactants, and / or cleaning agents, for example. In the illustrated example, sensing arrangements 320(1), 320(2) and 320(3) are disposed to sense, respectively, characteristics of gases (1) between the gas delivery arrangement 101 and the process station 102, (2) within the process station 102, and (3) between the process station 102 and the vacuum pump 118.

[0042] As described hereinabove, each sensing arrangement 320 may include one or more micro-electromechanical systems (MEMS) sensors configured to output signals indicative of chemical concentrations at each respective location of the system 300. Each MEMS sensor may include a field effect transistor with a sensing channel including a two-dimensional (2D) nanomaterial. The 2D nanomaterial may include graphene, a transition metal dichalcogenide (TMD) and / or black phosphorous and may further include nanoparticles of tin oxide (SNO2), tungsten trioxide (WO3), silver or platinum, or various combinations thereof. In some implementations, one or more sensing arrangement 320 may include a cantilever-based mass / vibration sensing device.

[0043] Figure 4 presents a flowchart of an example process 400 for measuring and controlling chemical concentration measurement in semiconductor fabrication equipment. Blocks of process 400 may be implemented by one or more processors or of a computing device or controller that may be included in or communicatively coupled with system controller 250, for example.

[0044] At block 402, process 400 may monitor outputs of a sensing arrangement coupled with the semiconductor fabrication equipment. As described hereinabove, the sensing arrangement may include one or more micro-electromechanical systems (MEMS) sensors configured to output signals indicative of chemical concentrations in at least one stage of the semiconductor fabrication equipment. Monitoring the outputs may includeprocessing, with a controller, the output signals to determine the chemical concentration in at least one stage of the semiconductor fabrication equipment.

[0045] At block 404, process 400 may, based on the monitored outputs, control an operational parameter of the semiconductor fabrication equipment. For example, the controller may make a comparison between the determined chemical concentration and a desired chemical concentration; and control the parameter responsive to the comparison.

[0046] Optionally, as indicated by dashed process flow line 405, the process 400 may be repeated, at intervals or continuously, so as to provide a substantially closed loop control process.

[0047] Optionally, as indicated by dashed decision block 406, the process 400 may include a determination as to whether or not the monitored outputs are within acceptable limits. If so, as indicated by dashed process flow line 407, the process 400 may be repeated, at intervals or continuously. If not, at block 408 the process may continue by, for example, taking a corrective action such as sounding an alarm, signaling an operator, initiating a soft shutdown of the semiconductor fabrication system, aborting an operation of the semiconductor fabrication system, or recommending further analysis and / or corrective action. A corrective action may further include, for example, changing gas flow, pressure, temperature, RF power, etc. to compensate for or minimize process drift.

[0048] A number of use cases for the presently disclosed techniques will now be described. In a first example use case, the monitored outputs relate to chemical concentration of process and / or carrier gases for use in a semiconductor fabrication process. The semiconductor fabrication process may be a deposition process, for example.

[0049] In a deposition process, for example, referring again to Figure 3, the gas delivery arrangement 101 may be configured to permit delivery of film precursor vapor or other process gases together with a carrier gas such as argon or nitrogen, for example. The process gases, in some implementations, may include one or more of tungsten hexaflouride (WF6), various chlorides of tungsten (e.g., WCh), various oxychlorides of molybdenum (MoOxCly), tetraethoxysilane (TEOS), diborane (B2H6), silane (SiFE), nitrogen trifluoride (NF3), ammonia (NH3), ammonium (NH4), methane (CH4), and carbon monoxide (CO), for example.

[0050] Sensing arrangements 320(1), 320(2) and 320(3) may sense, respectively, concentrations of the process or carrier gases (1) at an inlet to the process station 102, between the delivery arrangement 101 and the process station 102, (2) within the process station 102, and (3) at an outlet of the process station 102, between the process station 102and the vacuum pump 118. Each of sensing arrangements 320(1), 320(2) and 320(3) may include multiple variously configured sensing elements (e.g., MEMS sensors), each respectively configured to sense chemical concentrations of different chemical species. In some implementations, one sensor may be configurable to selectively sense more than one species as a result of, for example, diverse adsorption and / or electrical properties. The sensing arrangements 320 are communicatively coupled with a controller 350 that is also communicatively coupled with the gas delivery arrangement 101.

[0051] The controller 350 may be configured to monitor output signals from the sensing arrangements 320, and process the output signals to determine the chemical concentration of process and / or carrier gases in the process station 102, at the inlet of the process station 102 and / or at the outlet of the process station 102. The controller 350 may further be configured to make a comparison between the determined chemical concentration and a desired chemical concentration and, responsive to the comparison controlling an operating parameter of the gas delivery arrangement 101. For example, the controller 350 may actuate flow and / or pressure control mechanisms within gas delivery arrangement 101. For example, responsive to outputs of sensing arrangement 320(2), the controller may actuate flow and / or pressure control mechanisms including those disposed within gas delivery arrangement 101 so as to achieve and / or maintain a desired concentration of process gases within process station 102. As a further example, the controller may be configured to actuate flow and / or pressure control mechanisms, responsive to outputs of sensing arrangements 320(1), 320(2) and 320(3), so as to optimize processes (e.g., utilization efficiency of precursor vapors and / or duration of postdeposition purging of process station 102). For example, analysis of outputs of sensing arrangements 320(1), 320(2) and 320(3) may be used to minimize waste of process gases, resulting in reduced operating costs, and lessened environmental effects. As a further example, where a deposition process is followed by a purge process during which process gases are safely purged from the process station, the duration of such purge may be optimized, by using outputs of sensing arrangements 320(2) and / or 320(3) to determine when the process station 102 has been sufficiently purged of process gases. As a result, advantageously, process throughput may be increased and / or unnecessary equipment downtime may be reduced, while maintaining worker safety and environmental protections.

[0052] A second use case relates to cleaning of a process station after deposition operations. It should be appreciated that a deposition process unavoidably results inundesirable deposits on locations within the process station other than the substrate undergoing the deposition process. Periodic removal of these deposits may require the use of highly corrosive and toxic cleaning chemicals and reaction products thereof, including, for example, nitrogen trifluoride (NF3) and / or hydrogen fluoride (HF). To avoid hazards to personnel and the environment, such compounds must be safely purged from the process station during and after a cleaning procedure and prior to opening the process station to a laboratory environment. In the absence of the presently disclosed techniques, an RGA might be used to measure concentrations of hazardous gases, or a purging operation might be performed for a conservative time period shown by past experience to be sufficient. Advantageously, because RGAs are expensive and not always available and the conservative time period may mean unnecessarily prolonged equipment downtime, sensing arrangements using MEMS sensors as described hereinabove may be used. The MEMS sensors may be configured to output signals indicative of the chemical concentrations of the dangerous substances within the process station. For example, the controller 350 may be configured to monitor the output signals of sensing arrangement 320(2) and make a determination whether or not to open (or permit opening) of the process station, based on the monitored outputs.

[0053] Moreover, outputs from the MEMS sensors may be used as an indicator for life of a remote plasma clean system. For example, as the remote plasma clean system deteriorates with age, the concentrations of specific clean species created (e.g., atomic or molecular fluorine) would change, thereby providing an indication of cleaning efficiency and / or health of the remote plasma clean system under similar operating conditions. The system can compensate by changing the gas mixture ratio or power but also alert the user early of impacted life for future replacement as part of planned maintenance.

[0054] A further use case relates to a configuration of the gas delivery arrangement 101 in which the gas delivery arrangement 101 includes one or more containers, referred to herein as ampoules, for storing liquid or solid precursor chemicals. Referring to Figure 6, the gas delivery arrangement 101 includes ampoule 630, partially filled with precursor 640. Precursor vapor resulting from evaporation or sublimation of the liquid or solid precursor 640 may be carried by a carrier gas, such as argon, to the process station 102. Knowledge of and control over the chemical concentration of the resulting mixture, in the absence of the presently disclosed techniques is difficult to achieve, because, for example, the concentration may vary significantly depending on the fill level of the ampoule 630. As the ampoule 630 becomes depleted, the chemical concentration may decrease, but therate of decrease is difficult to accurately predict. As contemplated by the present disclosure, however, chemical concentrations may be measured by a sensing arrangement 320(4), including one or more MEMS sensors, disposed at or near the ampoule outlet, significantly reducing this uncertainty. Moreover, the controller 350 may be configured to actively control, responsive to outputs from the sensing arrangement 320(4), the chemical concentration by changing the flow rate of the carrier gas or the temperature of the ampoule 630.

[0055] A yet further use case relates to control of semiconductor fabrication equipment configured with a plurality of process stations, such as illustrated in Figure 2. The illustrated fabrication tool 200 employs a process chamber 214 that includes multiple fabrication process stations, each of which may be used to perform processing operations on a respective substrate. As illustrated in Figure 5, each process station of the process chamber 214 may be fluidically coupled with the gas delivery arrangement 101 by way of a control valve arrangement 505. Each respective station may include a sensing arrangement configured to detect a concentration of at least one of the process gases within the respective station. The controller 250, responsive to outputs from the respective sensing arrangements may be configured to maintain or adjust a pressure and / or flow rate of the carrier gas and / or the process gas at each respective station by controlling respective control valves of the control valve arrangement 505.

[0056] Yet other use cases are within the contemplation of the present disclosure. For example, sensing arrangements including MEMS sensors may be configured to measure concentrations of substances back streamed from a process station. As a further example, sensing arrangements including MEMS sensors may be configured to measure moisture and / or to detect leaks in a process station. As another example, sensing arrangements including MEMS sensors may be configured to detect encroaching gas flow from a process station that may impact performance of a tool such as substrate handler robot 206.

[0057] As a yet further example, one or more MEMS sensors may be used to detect a high risk of corrosion of components exposed, for example, to high temperature. In such environments, corrosion-prevention may rely on minimizing exposure of the at-risk components to oxygen by, for example, to purging a region surrounding the component with an inert gas such as nitrogen or argon, for example. A necessary / sufficient flow rate of the inert gases may be determined based on calculations and / or empirical data. But relying solely on such determined flow rates leaves open a risk that that a gas purge line may become obstructed or that an upstream purge gas pressure may be anomalously low,resulting in improperly high concentrations of oxygen. One or more MEMS sensors may be configured to detect for concentrations of oxygen species. If the concentration exceeds a threshold, a controller monitoring MEMS sensor outputs may, take a corrective action such as or more of changing gas flow, pressure or temperature, sounding an alarm, signaling an operator, initiating a soft shutdown of the fabrication equipment, aborting an operation of the fabrication equipment, or recommending further analysis and / or other corrective action.

[0058] The above described use cases mainly relate to implementations in which the semiconductor fabrication equipment is configured to perform deposition processes. Without limitation, however the semiconductor fabrication equipment, alternatively or in addition, may include an etch chamber or module, a spin-rinse chamber or module, a metal plating chamber or module, a clean chamber or module, an ion implantation chamber or module, a track chamber or module, and / or any other semiconductor processing systems that may be associated or used in the fabrication and / or manufacturing of semiconductor wafers. It should also be appreciated that non-plasma processes are also contemplated, for example chemical deposition or reaction processes may be thermally driven whether or not in the presence of plasma.

[0059] Depending on the process step or steps to be performed by the equipment, a controller (e.g., controller 250 or controller 350 may communicate with one or more of other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout a factory, a main computer, another controller, or tools used in material transport that bring containers of wafers to and from tool locations and / or load ports in a semiconductor manufacturing factory.

[0060] The controller, depending on the processing requirements and / or the type of system, may be programmed to control any of the processes disclosed herein, including the delivery of processing gases, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, positional and operation settings, wafer transfers into and out of a tool and other transfer tools and / or load locks connected to or interfaced with a specific system.

[0061] Broadly speaking, the controller may be defined as electronics having various integrated circuits, logic, memory, and / or software that receive instructions, issue instructions, control operation, enable cleaning operations, enable endpoint measurements, and the like. The integrated circuits may include chips in the form of firmware that storeprogram instructions, digital signal processors (DSPs), chips defined as application specific integrated circuits (ASICs), and / or one or more microprocessors, or microcontrollers that execute program instructions (e.g., software). Program instructions may be instructions communicated to the controller in the form of various individual settings (or program files), defining operational parameters for carrying out a particular process on or for a semiconductor wafer or to a system. The operational parameters may, in some embodiments, be part of a recipe defined by process engineers to accomplish one or more processing steps during the fabrication of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of a wafer.

[0062] The controller, in some implementations, may be a part of or coupled to a computer that is integrated with, coupled to the system, otherwise networked to the system, or a combination thereof. For example, the controller may be in the “cloud” or all or a part of a fab host computer system, which can allow for remote access of the wafer processing. The computer may enable remote access to the system to monitor current progress of fabrication operations, examine a history of past fabrication operations, examine trends or performance metrics from a plurality of fabrication operations, to change parameters of current processing, to set processing steps to follow a current processing, or to start a new process. In some examples, a remote computer (e.g. a server) can provide process recipes to a system over a network, which may include a local network or the Internet. The remote computer may include a user interface that enables entry or programming of parameters and / or settings, which are then communicated to the system from the remote computer. In some examples, the controller receives instructions in the form of data, which specify parameters for each of the processing steps to be performed during one or more operations. It should be understood that the parameters may be specific to the type of process to be performed and the type of tool that the controller is configured to interface with or control. Thus as described above, the controller may be distributed, such as by comprising one or more discrete controllers that are networked together and working towards a common purpose, such as the processes and controls described herein. An example of a distributed controller for such purposes would be one or more integrated circuits on a chamber in communication with one or more integrated circuits located remotely (such as at the platform level or as part of a remote computer) that combine to control a process on the chamber.CONCLUSION

[0063] In the description, numerous specific details were set forth in order to provide a thorough understanding of the presented embodiments. The disclosed embodiments may be practiced without some or all of these specific details. In other instances, well-known process operations were not described in detail to not unnecessarily obscure the disclosed embodiments. While the disclosed embodiments were described in conjunction with the specific embodiments, it will be understood that the specific embodiments are not intended to limit the disclosed embodiments.

[0064] Numeric ranges are inclusive of the numbers defining the range. It is intended that every maximum numerical limitation given throughout this specification includes every lower numerical limitation, as if such lower numerical limitations were expressly written herein. Every minimum numerical limitation given throughout this specification will include every higher numerical limitation, as if such higher numerical limitations were expressly written herein. Every numerical range given throughout this specification will include every narrower numerical range that falls within such broader numerical range, as if such narrower numerical ranges were all expressly written herein.

[0065] The headings provided herein are not intended to limit the disclosure.

[0066] As used herein, the singular terms “a,” “an,” and “the” include the plural reference unless the context clearly indicates otherwise. The term “or” as used herein, refers to a non-exclusive or, unless otherwise indicated.

[0067] Various computational elements including processors, memory, instructions, routines, models, or other components may be described or claimed as “configured to” perform a task or tasks. In such contexts, the phrase “configured to” is used to connote structure by indicating that the component includes structure (e.g., stored instructions, circuitry, etc.) that performs the task or tasks during operation. As such, the unit / circuit / component can be said to be configured to perform the task even when the specified component is not necessarily currently operational (e.g., is not on).

[0068] The components used with the “configured to” language may refer to hardware — for example, circuits, memory storing program instructions executable to implement the operation, etc. Additionally, “configured to” can refer to generic structure (e.g., generic circuitry) that is manipulated by software and / or firmware (e.g., an FPGA or a general-purpose processor executing software) to operate in manner that is capable of performing the recited task(s). Additionally, “configured to” can refer to one or more memories or memory elements storing computer executable instructions for performingthe recited task(s). Such memory elements may include memory on a computer chip having processing logic. In some contexts, “configured to” may also include adapting a manufacturing process (e.g., a semiconductor fabrication facility) to fabricate devices (e.g., integrated circuits) that are adapted to implement or perform one or more tasks.

[0069] It is to be understood that the above disclosure, while focusing on a particular example implementation or implementations, is not limited to only the discussed example, but may also apply to similar variants and mechanisms as well, and such similar variants and mechanisms are also considered to be within the scope of this disclosure. For example, the above disclosure is directed to at least, but not exclusively, the following numbered implementations.

[0070] Implementation 1. A method of chemical concentration measurement and control of semiconductor fabrication equipment, the method comprising: monitoring, during an operation of the semiconductor fabrication equipment, outputs of a sensing arrangement coupled with the semiconductor fabrication equipment, the sensing arrangement comprising at least one micro-electromechanical system (MEMS) sensor configured to output signals indicative of a chemical concentration in at least one stage of the semiconductor fabrication equipment; and, based on the monitored outputs, controlling a parameter of the operation.

[0071] Implementation 2. The method of implementation 1, further comprising, based on the monitored outputs, one or more of: taking a corrective action, sounding an alarm, signaling an operator, initiating a soft shutdown of the fabrication equipment, aborting an operation of the fabrication equipment, or recommending further analysis and / or other corrective actions.

[0072] Implementation 3. The method of implementation 2, wherein the corrective action includes one or more of changing gas flow, pressure, temperature, and / or RF power.

[0073] Implementation 4. The method of implementation 1, wherein the MEMS sensor comprises a field effect transistor with a sensing channel comprising a two-dimensional (2D) nanomaterial.

[0074] Implementation 5. The method of implementation 4, wherein the 2D nanomaterial comprises graphene, a transition metal dichalcogenide (TMD) and / or black phosphorous.

[0075] Implementation 6. The method of implementation 5, wherein the 2D nanomaterial further comprises nanoparticles of tin oxide (SNO2), tungsten trioxide (WO3), silver or platinum, or a combination thereof.

[0076] Implementation 7. The method of implementation 1, wherein the MEMS sensor includes a cantilever-based mass / vibration sensing device.

[0077] Implementation 8. The method of implementation 1, wherein monitoring the outputs includes processing, with a controller, the outputted signals to determine a chemical concentration measurement in the at least one stage of the semiconductor fabrication equipment.

[0078] Implementation 9. The method of implementation 8, wherein the controlling the parameter further comprises: the controller making a comparison between the determined chemical concentration and a desired chemical concentration; and controlling the parameter responsive to the comparison.

[0079] Implementation 10. The method of implementation 1, further comprising repeating the monitoring outputs and the controlling the parameter, continuously, or at intervals, as a closed loop control process.

[0080] Implementation 11. The method of implementation 1, wherein the sensing arrangement comprises a plurality of MEMS sensors, each of the MEMS sensors being configured to output respective signals indicative of a chemical concentration of a respective chemical species in the at least one stage of the semiconductor fabrication equipment.

[0081] Implementation 12. The method of implementation 11, wherein: the at least one stage includes a process station, and the operation includes a deposition process performed within the process station; the semiconductor fabrication equipment comprises a source of a carrier gas and one or more sources of process gases for performing the deposition process; the sensing arrangement is configured to detect a concentration of at least one of the process gases; and the controlling the parameter of the operation includes maintaining or adjusting a pressure and / or flow rate of the carrier gas and / or the process gas.

[0082] Implementation 13. The method of implementation 12, wherein at least one of the process gases includes tungsten hexaflouride (WF6), a chloride of tungsten, an oxychloride of molybdenum, tetraethoxysilane (TEOS), silane (SiH4), diborane (B2H6), ammonia (NH3), ammonium (NH4), or nitrogen trifluoride (NF3), methane (CH4), and / or carbon monoxide (CO).

[0083] Implementation 14. The method of implementation 12, wherein the plurality of MEMS sensors includes at least one MEMS sensor located at an inlet of the process station and at least one MEMS sensor located at an outlet of the process station.

[0084] Implementation 15. The method of implementation 13, wherein at least one MEMS sensor is located within the process station.

[0085] Implementation 16. The method of implementation 14, further comprising controlling radio frequency (RF) generator settings and / or actuating flow and / or pressure control mechanisms, responsive to the outputted respective signals so as to obtain a desired chemical concentration of at least one of the process gases within the process station, at the inlet of the process station and / or at the outlet of the process station.

[0086] Implementation 17. The method of implementation 15, wherein: the operation includes a purging process, performed after the deposition process, the purging process configured to remove at least the process gases from the process station; and the method includes determining, from the outputted respective signals, whether or not the process gases have been sufficiently removed.

[0087] Implementation 18. The method of implementation 12, wherein: the semiconductor fabrication equipment includes multiple stations for performing a deposition process, each respective station comprising a sensing arrangement configured to detect a concentration of at least one of the process gases for the respective station; and the controlling the parameter includes controlling radio frequency (RF) generator settings and / or maintaining or adjusting a pressure and / or flow rate of the carrier gas and / or the process gas at each respective station.

[0088] Implementation 19. The method of implementation 12, wherein the operation includes cleaning the process station and the outputted respective signals are indicative of a chemical concentration of cleaning compounds or byproducts thereof.

[0089] Implementation 20. The method of implementation 19, wherein the cleaning compounds or byproducts include nitrogen trifluoride (NF3), atomic fluorine (F), molecular fluorine (F2) and / or hydrogen fluoride (HF).

[0090] Implementation 21. The method of implementation 19, wherein the operation includes cleaning the process station with a remote plasma clean system and the outputted respective signals are indicative of a cleaning efficiency and / or health of the remote plasma clean system.

[0091] Implementation 22. The method of implementation 19, wherein the controlling the parameter of the operation includes determining, from the outputted respective signals whether or not the process station is safe to open.

[0092] Implementation 23. The method of implementation 12, wherein at least one of the one or more sources of process gases comprises an ampoule configured to produce theprocess gas from a solid or liquid precursor chemical contained in the ampoule, and the sensing arrangement includes at least one micro-electromechanical system (MEMS) sensor disposed proximal to an ampoule outlet and configured to measure chemical concentrations of the process gas proximal to the ampoule outlet.

[0093] Implementation 24. The method of implementation 11, wherein the respective chemical species in the at least one stage of the semiconductor fabrication equipment include oxygen, and monitoring the outputs of the sensing arrangement includes determining whether an indicated concentration of oxygen represents a corrosion risk.

[0094] Implementation 25. An apparatus for monitoring semiconductor fabrication equipment, the apparatus comprising: a sensing arrangement coupled with the semiconductor fabrication equipment, the sensing arrangement comprising at least one micro-electromechanical system (MEMS) sensor configured to output signals indicative of a chemical concentration in at least one stage of the semiconductor fabrication equipment during an operation of the semiconductor fabrication equipment; wherein: the sensing arrangement is communicatively coupled with a controller, the controller being configured to monitor outputs of the sensing arrangement and comprising logic configured to control, based on the monitored outputs, an operational parameter of the semiconductor fabrication equipment.

[0095] Implementation 26. The apparatus of implementation 25, wherein the logic is further configured to control, based on the monitored outputs, a corrective action, one or more of: sounding an alarm, signaling an operator, initiating a soft shutdown of the fabrication equipment, aborting an operation of the fabrication equipment, or recommending further analysis and / or other corrective action.

[0096] Implementation 27. The apparatus of implementation 26, wherein the corrective action includes one or more of changing gas flow, pressure, temperature, and / or RF power.

[0097] Implementation 28. The apparatus of implementation 25, wherein the MEMS sensor comprises a field effect transistor with a sensing channel comprising a two-dimensional (2D) nanomaterial.

[0098] Implementation 29. The apparatus of implementation 28, wherein the 2D nanomaterial comprises graphene, a transition metal dichalcogenide (TMD) and / or black phosphorous.

[0099] Implementation 30. The apparatus of implementation 29, wherein the 2D nanomaterial further comprises nanoparticles of tin oxide (SNO2), tungsten trioxide (WO3), silver or platinum, or a combination thereof.

[0100] Implementation 31. The apparatus of implementation 25, wherein the MEMS sensor includes a cantilever-based mass / vibration sensing device.

[0101] Implementation 32. The apparatus of implementation 25, wherein the controller is further configured to process the outputted signals to determine a chemical concentration measurement in the at least one stage of the semiconductor fabrication equipment.

[0102] Implementation 33. The apparatus of implementation 25, wherein the sensing arrangement comprises a plurality of MEMS sensors, each of the MEMS sensors being configured to output signals indicative of a chemical concentration of a respective chemical species in the at least one stage of the semiconductor fabrication equipment.

[0103] Implementation 34. The apparatus of implementation 33, wherein: the at least one stage includes a process station, and the operation includes a deposition process performed within the process station; the semiconductor fabrication equipment comprises a carrier gas source and one or more sources of process gases for performing the deposition process; the sensing arrangement is configured to detect a concentration of at least one of the process gases; and the controlling the parameter of the operation includes maintaining or adjusting a pressure and / or flow rate of the carrier gas and / or the process gas.

[0104] Implementation 35. The apparatus of implementation 34, wherein at least one of the process gases includes tungsten hexaflouride (WF6), a chloride of tungsten, an oxychloride of molybdenum, tetraethoxysilane (TEOS), silane (SiH4), diborane (B2H6), ammonia (NH3), ammonium (NH4), or nitrogen trifluoride (NF3), methane (CH4), and / or carbon monoxide (CO).

[0105] Implementation 36. The apparatus of implementation 35, wherein the plurality of MEMS sensors includes at least one MEMS sensor located at an inlet of the process station, and at least one MEMS sensor located at an outlet of the process station.

[0106] Implementation 37. The apparatus of implementation 36, wherein the plurality of MEMS sensors includes at least one MEMS sensor located within the process station.

[0107] Implementation 38. The apparatus of implementation 36, wherein: the operation includes a purging process, performed after the deposition process, the purging process configured to remove at least the process gases from the process station; and thecontroller is configured to determine, from the monitored outputted respective signals, whether or not the process gases have been sufficiently removed.

[0108] Implementation 39. The apparatus of implementation 36, wherein: the semiconductor fabrication equipment includes multiple stations for performing a deposition process, each respective station comprising a sensing arrangement configured to detect a concentration of at least one of the process gases for the respective station; and the controlling the parameter includes maintaining or adjusting a pressure and / or flow rate of the carrier gas and / or the process gas at each respective station.

[0109] Implementation 40. The apparatus of implementation 36, wherein the operation includes cleaning the process station and the outputted respective signals are indicative of a chemical concentration of cleaning compounds or byproducts thereof.

[0110] Implementation 41. The apparatus of implementation 40, wherein the cleaning compounds or byproducts include nitrogen trifluoride (NF3) and / or hydrogen fluoride (HF).

[0111] Implementation 42. The apparatus of implementation 40, wherein the controlling the parameter of the operation includes determining, from the outputted respective signals whether or not the process station is safe to open.

[0112] Implementation 43. The apparatus of implementation 34, wherein at least one of the one or more sources of process gases comprises an ampoule configured to produce the process gas from a solid or liquid precursor chemical contained in the ampoule, and the sensing arrangement includes at least one micro-electromechanical system (MEMS) sensor disposed proximal to an ampoule outlet and configured to measure chemical concentrations of the process gas proximal to the ampoule outlet.

[0113] Implementation 44. The apparatus of implementation 25, wherein the sensing arrangement is configured to output signals indicative of a chemical concentration of one or more of water, hydrogen, oxygen, tungsten hexaflouride (WF6), a chloride of tungsten, an oxychloride of molybdenum, tetraethoxysilane (TEOS), silane (SiH4), diborane (B2H6), ammonia (NH3), ammonium (NH4), or nitrogen trifluoride (NF3), methane (CH4), and / or carbon monoxide (CO), nitrogen trifluoride (NF3) and / or hydrogen fluoride (HF).

Claims

CLAIMSWhat is claimed is:

1. A method of chemical concentration measurement and control of semiconductor fabrication equipment, the method comprising:monitoring, during an operation of the semiconductor fabrication equipment, outputs of a sensing arrangement coupled with the semiconductor fabrication equipment, the sensing arrangement comprising at least one micro-electromechanical system (MEMS) sensor configured to output signals indicative of a chemical concentration in at least one stage of the semiconductor fabrication equipment; and,based on the monitored outputs, controlling a parameter of the operation.

2. The method of claim 1, further comprising, based on the monitored outputs, one or more of: taking a corrective action, sounding an alarm, signaling an operator, initiating a soft shutdown of the fabrication equipment, aborting an operation of the fabrication equipment, or recommending further analysis and / or other corrective actions, changing gas flow, pressure, temperature, and / or RF power.

3. The method of claim 1, wherein monitoring the outputs includes processing, with a controller, the outputted signals to determine a chemical concentration measurement in the at least one stage of the semiconductor fabrication equipment.

4. The method of claim 1, wherein the sensing arrangement comprises a plurality of MEMS sensors, each of the MEMS sensors being configured to output respective signals indicative of a chemical concentration of a respective chemical species in the at least one stage of the semiconductor fabrication equipment.

5. The method of claim 4, wherein:the at least one stage includes a process station, and the operation includes a deposition process performed within the process station;the semiconductor fabrication equipment comprises a source of a carrier gas and one or more sources of process gases for performing the deposition process;the sensing arrangement is configured to detect a concentration of at least one of the process gases; andthe controlling the parameter of the operation includes maintaining or adjusting a pressure and / or flow rate of the carrier gas and / or the process gas.

6. The method of claim 5, wherein at least one of the process gases includes tungsten hexaflouride (WF6), a chloride of tungsten, an oxychloride of molybdenum, tetraethoxysilane (TEOS), silane (SiH4), diborane (B2H6), ammonia (NH3), ammonium (NH4), or nitrogen trifluoride (NF3), methane (CH4), and / or carbon monoxide (CO).

7. The method of claim 6, further comprising controlling radio frequency (RF) generator settings and / or actuating flow and / or pressure control mechanisms, responsive to the outputted respective signals so as to obtain a desired chemical concentration of at least one of the process gases within the process station, at an inlet of the process station and / or at an outlet of the process station.

8. The method of claim 6, wherein:the operation includes a purging process, performed after the deposition process, the purging process configured to remove at least the process gases from the process station; andthe method includes determining, from the outputted respective signals, whether or not the process gases have been sufficiently removed.

9. The method of claim 5, wherein the operation includes cleaning the process station and the outputted respective signals are indicative of a chemical concentration of cleaning compounds or byproducts thereof.

10. The method of claim 9, wherein the operation includes cleaning the process station with a remote plasma clean system and the outputted respective signals are indicative of a cleaning efficiency and / or health of the remote plasma clean system.

11. An apparatus for monitoring semiconductor fabrication equipment, the apparatus comprising:a sensing arrangement coupled with the semiconductor fabrication equipment, the sensing arrangement comprising at least one micro-electromechanical system (MEMS) sensor configured to output signals indicative of a chemical concentration in at least one stage ofthe semiconductor fabrication equipment during an operation of the semiconductor fabrication equipment; wherein:the sensing arrangement is communicatively coupled with a controller, the controller being configured to monitor outputs of the sensing arrangement and comprising logic configured to control, based on the monitored outputs, an operational parameter of the semiconductor fabrication equipment.

12. The apparatus of claim 11, wherein:the logic is further configured to control, based on the monitored outputs, a corrective action, one or more of: sounding an alarm, signaling an operator, initiating a soft shutdown of the fabrication equipment, aborting an operation of the fabrication equipment, or recommending further analysis and / or other corrective action, changing gas flow, pressure, temperature, and / or RF power.

13. The apparatus of claim 11, wherein the MEMS sensor comprises a field effect transistor with a sensing channel comprising a two-dimensional (2D) nanomaterial.

14. The apparatus of claim 11, wherein the MEMS sensor includes a cantilever-based mass / vibration sensing device.

15. The apparatus of claim 11, wherein the sensing arrangement comprises a plurality of MEMS sensors, each of the MEMS sensors being configured to output signals indicative of a chemical concentration of a respective chemical species in the at least one stage of the semiconductor fabrication equipment.

16. The apparatus of claim 15, wherein:the at least one stage includes a process station, and the operation includes a deposition process performed within the process station;the semiconductor fabrication equipment comprises a carrier gas source and one or more sources of process gases for performing the deposition process;the sensing arrangement is configured to detect a concentration of at least one of the process gases; andthe controlling the parameter of the operation includes maintaining or adjusting a pressure and / or flow rate of the carrier gas and / or the process gas.

117. The apparatus of claim 16, wherein the plurality of MEMS sensors includes at least one MEMS sensor located at an inlet of the process station, and at least one MEMS sensor located at an outlet of the process station.

18. The apparatus of claim 17, wherein the plurality of MEMS sensors includes at least one MEMS sensor located within the process station.

19. The apparatus of claim 16, wherein at least one of the one or more sources of process gases comprises an ampoule configured to produce the process gas from a solid or liquid precursor chemical contained in the ampoule, and the sensing arrangement includes at least one micro-electromechanical system (MEMS) sensor disposed proximal to an ampoule outlet and configured to measure chemical concentrations of the process gas proximal to the ampoule outlet.

20. The apparatus of claim 11, wherein the sensing arrangement is configured to output signals indicative of a chemical concentration of one or more of water, hydrogen, oxygen, tungsten hexaflouride (WF6), a chloride of tungsten, an oxychloride of molybdenum, tetraethoxysilane (TEOS), silane (SiH4), diborane (B2H6), ammonia (NH3), ammonium (NH4), or nitrogen trifluoride (NF3), methane (CH4), and / or carbon monoxide (CO), nitrogen trifluoride (NF3) and / or hydrogen fluoride (HF).

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