Vacuum pump protection to avoid deposition by-product build-up

Abstract

A processing chamber (e.g., a plasma etch chamber) may perform deposition and etch operations where by-products of the deposition and etch operations may accumulate in a vacuum pump system fluidly coupled with the processing chamber. The vacuum pump system may have a plurality of roughing pumps such that the etching gas may be shunted to one roughing pump and the deposition precursor may be shunted to another roughing pump. The shunt line may direct unused deposition precursor through a separate roughing pump. By incorporating one or more gas injectors or venturi pumps at the outlet of the primary pump in the vacuum pump system, deposition by-product formation may be avoided. Cleaning operations using certain cleaning chemicals (e.g., wafer-less auto-cleaning operations) may remove deposition byproducts before or after the etch operation.

Description

This application is a divisional application of the invention patent application with application number 201980078104.5, application date September 26, 2019, applicant is Rum Research Company, and invention name is "Vacuum pump protection to avoid accumulation of deposition by-products". Incorporated by Reference

[0001] The PCT application form is filed concurrently with this specification as a part of this application. Each application to which this application claims the benefit of or priority as identified in the concurrently filed PCT application form is incorporated herein by reference in its entirety and for all purposes. Background Art

[0002] Vacuum pumps are widely used in semiconductor processing equipment to provide a clean and / or low-pressure environment within the process chamber. Such vacuum pumps can be fluidly connected to the process chamber to remove byproducts and unused etch and deposition precursors. Some vacuum pumps may be susceptible to the accumulation of undesirable byproducts caused by mixing of etch and deposition precursors, which can corrode or degrade the vacuum pump over time.

[0003] The background description provided here is for the purpose of generally presenting the context of the present disclosure. No admission is made, either explicitly or implicitly, that the work of the presently designated inventors is prior art to the present disclosure to the extent that it is described in this background section and in aspects of the specification that were not determined to be prior art at the time the application was filed. Summary of the Invention

[0004] The present invention provides an apparatus comprising: a processing chamber; an etching gas delivery system configured to introduce one or more etching gases into the processing chamber; a deposition precursor delivery system configured to introduce one or more deposition precursors into the processing chamber; and a vacuum pump system in fluid communication with the processing chamber. The vacuum pump system comprises: a first roughing pump; a second roughing pump; and a turbomolecular pump, the turbomolecular pump being in fluid communication with one or both of the first roughing pump and the second roughing pump.

[0005] In some embodiments, the vacuum pump system is configured to direct the one or more etching gases through the first roughing pump and the one or more deposition precursors through the second roughing pump. In some embodiments, the vacuum pump system further comprises: a foreline in fluid communication with the process chamber and configured to receive the one or more etching gases and the one or more deposition precursors from the process chamber; and a valve coupled to the foreline and configured to direct the one or more etching gases through the first roughing pump at a first position and to direct the one or more deposition precursors through the second roughing pump at a second position. In some embodiments, the vacuum pump system further comprises: a shunt line in fluid communication with the deposition precursor delivery system, wherein the shunt line is configured to shunt unused deposition precursors from the deposition precursor delivery system through the second roughing pump. In some embodiments, the one or more etching gases comprise hydrogen bromide (HBr), and the one or more deposition precursors comprise an aminosilane precursor.

[0006] Another aspect of the present disclosure includes a vacuum pump system for exhausting one or more etching gases and one or more deposition precursors from a process chamber. The vacuum pump system includes a first roughing pump for receiving the one or more etching gases from the process chamber; and a second roughing pump for receiving the one or more deposition precursors from the process chamber, wherein one or both of the first roughing pump and the second roughing pump are configured to be in fluid communication with a turbomolecular pump.

[0007] In some embodiments, the vacuum pump system further includes: a foreline in fluid communication with the processing chamber and configured to receive the one or more etching gases and the one or more deposition precursors from the processing chamber; and a valve coupled to the foreline and configured to direct the one or more etching gases through the first roughing pump at a first position and to direct the one or more deposition precursors through the second roughing pump at a second position.

[0008] Another aspect of the present disclosure includes a vacuum pump system for exhausting one or more etching gases and one or more deposition precursors from a process chamber. The vacuum pump system includes a first roughing pump for receiving the one or more etching gases and the one or more deposition precursors from the process chamber; and a second roughing pump for receiving unused deposition precursors from a deposition cycle, wherein one or both of the first roughing pump and the second roughing pump are configured to be in fluid communication with a turbomolecular pump.

[0009] In some embodiments, the vacuum pump system is configured to direct the one or more etching gases and the one or more deposition precursors through the first roughing pump, and to direct unused deposition precursors from a deposition cycle through the second roughing pump. In some embodiments, the vacuum pump system further comprises a shunt line in fluid communication with the deposition precursor delivery system, wherein the shunt line is configured to shunt unused deposition precursors from a deposition cycle from the deposition precursor delivery system through the second roughing pump. In some embodiments, the one or more etching gases comprise hydrogen bromide (HBr) and the one or more deposition precursors comprise an aminosilane precursor.

[0010] Another aspect of the present disclosure includes a method for cleaning a vacuum pump system. The method includes performing one or more deposition operations on a wafer in a processing chamber; performing one or more etching operations on the wafer in the processing chamber; and performing a cleaning operation using a reactive gas flowing through the vacuum pump system, the cleaning operation being performed before or after the one or more etching operations, wherein the vacuum pump system is in fluid communication with the processing chamber.

[0011] In some embodiments, performing the cleaning operation is performed between a deposition operation and an etching operation. In some embodiments, performing the one or more deposition operations, the one or more etching operations, and the cleaning operation is performed when a wafer is present in the treatment chamber. In some embodiments, performing the cleaning operation is performed when a wafer is not present in the treatment chamber. In some embodiments, the reactive gas comprises nitrogen trifluoride (NF3), sulfur hexafluoride (SF6), carbon tetrafluoride (CF4), chlorine trifluoride (ClF3), chlorine (Cl2), oxygen (O2), ozone (O3), or a combination thereof. In some embodiments, the reactive gas comprises ozone. In some embodiments, the method further comprises: generating the reactive gas in situ in the treatment chamber by a plasma reaction. In some embodiments, the method further comprises: generating the reactive gas by a plasma source located in a foreline, wherein the foreline provides an interconnection between the vacuum pump system and the treatment chamber. In some embodiments, the method further includes generating the reactive gas via a remote plasma source located external to a foreline, wherein the foreline provides an interconnection between the vacuum pump system and the processing chamber.

[0012] Another aspect of the present disclosure includes a vacuum pump system for exhausting one or more etching gases and one or more deposition precursors from a process chamber. The vacuum pump system includes a roughing pump through which the deposition precursors and etching gases are exhausted from the process chamber; and a gas ejector connected in series with the roughing pump and located downstream of the roughing pump, wherein the gas ejector is configured to reduce the pressure at an outlet of the roughing pump.

[0013] In some embodiments, the gas ejector is a venturi pump connected to the outlet of the roughing pump, wherein the venturi pump is configured to flow an injection gas through the body of the venturi pump and mix with the discharged deposition precursor and etching gas in the body of the venturi pump. In some embodiments, the injection gas comprises an inert gas, clean dry air, or nitrogen (N2). In some embodiments, the vacuum pump system further comprises an abatement assembly configured to process the deposition precursor and the discharged gas, wherein the gas ejector is located between the abatement assembly and the roughing pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1A is a schematic diagram of an exemplary processing apparatus for performing etching and deposition operations, according to some embodiments.

[0015] Figure 1B is a schematic diagram of an exemplary vacuum pump system including a roughing pump used in series with a turbomolecular pump, according to some embodiments.

[0016] Figure 2A is a schematic diagram of an exemplary processing apparatus including a "completely split" vacuum pump system having two separate pumps, according to some embodiments.

[0017] Figure 2B is a schematic diagram of an exemplary processing apparatus including a "bypass split" vacuum pump system having two separate pumps, according to some embodiments.

[0018] Figure 2C is a schematic diagram of an exemplary processing apparatus including a "multi-inlet" vacuum pump system operating at different pressure stages, according to some embodiments.

[0019] Figure 3 An example of a rotor assembly in a vacuum pump system is shown according to some embodiments.

[0020] Figure 4 A flow chart is shown of an exemplary method of a cleaning process for preventing accumulation of deposition byproducts in a vacuum pump system, according to some embodiments.

[0021] Figure 5 is a schematic diagram of an exemplary vacuum pump system including a roughing pump having an outlet in fluid communication with an abatement assembly.

[0022] Figure 6 is a schematic cross-sectional view of an exemplary venturi pump showing the pressure gradient across the length of the venturi pump, according to some embodiments.

[0023] Figure 7 An exemplary venturi pump having components configured to connect to a vacuum pump system is shown according to some embodiments.

[0024] Figure 8A A schematic diagram of an exemplary vacuum pump system including a roughing pump modified to be connected in series with a gas ejector is shown, according to some embodiments.

[0025] Figure 8B A schematic diagram of an exemplary vacuum pump system including a roughing pump connected in series with a gas ejector is shown, according to some embodiments.

[0026] Figure 8C A schematic diagram of an exemplary vacuum pump system including a roughing pump connected in series with a plurality of gas ejectors is shown, according to some embodiments.

[0027] Figure 9 A schematic diagram of an exemplary vacuum pumping system including multiple venturi pumps serving as multi-stage venturi pre-pumps of the vacuum pumping system is shown, according to some embodiments. DETAILED DESCRIPTION

[0028] In the present disclosure, the terms "semiconductor wafer," "wafer," "substrate," "wafer substrate," and "partially processed integrated circuit" are used interchangeably. It will be understood by those skilled in the art that the term "partially processed integrated circuit" can refer to a silicon wafer during any of many stages of integrated circuit processing. Wafers or substrates used in the semiconductor device industry typically have a diameter of 200 mm, or 300 mm, or 450 mm. The following detailed description assumes that the present disclosure is implemented on a wafer. However, the present disclosure is not so limited. The workpiece can be of various shapes, sizes, and materials. In addition to semiconductor wafers, other workpieces that can utilize the present disclosure include various items, such as printed circuit boards, etc. introduction

[0029] Conventionally, deposition and etching processes are performed on separate tools or platforms. For example, a deposition chamber typically does not perform an etching process, while an etching chamber typically does not perform a deposition process. In some embodiments, an apparatus may be configured to perform deposition and etching processes in a single process chamber. For example, an atomic layer deposition (ALD) process and an etching process may be performed in a process chamber such as a plasma etch chamber. When both an ALD process and an etching process are performed on a wafer in the process chamber, deposition precursors and etching gases flow through the process chamber and may be exhausted by a vacuum pump system.

[0030] Unreacted deposition precursors and etching gases can be discharged through a vacuum pump system coupled to the processing chamber fluid. Unreacted deposition precursors and etching gases may mix in the vacuum pump system and form undesirable byproducts that may damage the pump equipment. In some cases, deposition byproducts may accumulate in the roughing pump of the vacuum pump system, where the deposition byproducts degrade the roughing pump, thereby reducing its performance and life. Without being limited by any theory, after the deposition or etching operation, process chemicals (such as deposition precursors, etching gases, or reaction products) remain in the roughing pump, and chemical reactions with the retained chemicals subsequently occur, and the same process chemicals flow through the roughing pump. For example, acidic gases such as hydrogen bromide (HBr) may react with the iron components of the roughing pump to form ferric bromide, which is a Lewis acid catalyst. When subsequently exposed to a deposition precursor (such as an aminosilane precursor gas), several reactions may occur, which result in the formation of deposition byproducts that are less volatile than the original aminosilane precursor gas. The accumulation of deposition byproducts in the pump may cause early failure of the pump. In some cases, the deposition byproducts may be a dark, tar-like substance. The accumulation of deposition byproducts reduces the practicality of using the deposition precursor and the etching gas together in a single processing chamber.

[0031] The present invention relates to methods and apparatus for removing deposition byproducts from a vacuum pump system or preventing the formation of deposition byproducts in the vacuum pump system. In some embodiments, deposition and etching gases can be discharged separately via separate pumps in fluid communication with the processing chamber. In some embodiments, the pump can have multiple inlets so that the pump can access the processing chamber depending on the operating pressure of the pump. In some embodiments, the internal surfaces of the pump are heated to an elevated temperature to vaporize deposition byproducts or prevent surface reactions that form deposition byproducts. In some embodiments, the internal surfaces of the pump are coated with a corrosion-resistant material to avoid or minimize surface reactions that would otherwise form deposition byproducts. In some embodiments, a purge time is determined so that the purge operation performed between deposition and etching operations is sufficient to remove etching gases and deposition precursors from the vacuum pump system. In some embodiments, a reactive gas can be used in the cleaning operation to remove deposition byproducts or deposition / etching gases from the vacuum pump system. The cleaning chemical can include oxygen, ozone, or a combination thereof. The cleaning chemical can include a fluorine-containing substance, a chlorine-containing substance, a bromine-containing substance, an iodine-containing substance, or a combination thereof. In some embodiments, one or more gas ejectors or venturi pumps may be positioned downstream of the roughing pump to reduce the discharge pressure at the outlet of the roughing pump. In some embodiments, multiple gas ejectors or venturi pumps may be used as primary pumps to create at least a "rough" vacuum in the process chamber. One or more of the aforementioned embodiments may be combined to prevent accumulation of deposition byproducts. Integrated etch / deposition equipment

[0032] Figure 1A FIG2 is a schematic diagram of an exemplary processing apparatus for performing etching and deposition operations according to some embodiments. The processing apparatus 100 may be an inductively coupled plasma processing apparatus. The processing apparatus 100 includes a plasma chamber 132, such as a plasma etch chamber. In some embodiments, the Kiyo is manufactured by Lam Research, Inc. of Fremont, California. TM A reactor is an example of a suitable reactor that can be used as the plasma etch chamber.

[0033] Details regarding the processing chamber 100 for performing etching and deposition operations are described in U.S. patent application Ser. No. 15 / 669,871, filed by Zhou et al. on Aug. 4, 2017, and entitled “INTEGRATED ATOMIC LAYER PASSIVATION IN TCP ETCH CHAMBER AND IN-SITU ETCH-ALP METHOD,” which is incorporated herein by reference in its entirety for all purposes.

[0034] The plasma chamber 132 may include a unitary chamber structure defined by chamber walls 114 and a window 106. The window 106 may be made of quartz or other dielectric materials. In some embodiments, the plasma chamber 132 includes a substrate support 116 disposed within the plasma chamber 132. In some embodiments, the substrate support 116 is an electrostatic chuck that supports the substrate 112 while the deposition / etching process is performed on the substrate 112. The electrostatic chuck may include electrostatic electrodes that are used to clamp and unclamp the substrate 112. Filters and a DC clamped power supply (not shown) may be provided for this purpose. Other control systems may also be provided for lifting the substrate 112 off the substrate support 116. The substrate support 116 is configured to receive and hold the substrate 112.

[0035] In some embodiments, the substrate support 116 may include a heater (not shown) to heat the substrate 112. The substrate support 116 may operate at an elevated temperature, for example, between about -20°C and about 150°C. This temperature will depend on the process operation and the specific recipe. In some embodiments, the plasma chamber 132 may also operate at a pressure, for example, between about 1 mTorr and about 1 Torr.

[0036] In some embodiments, the processing apparatus 100 may include a radio frequency (RF) power supply 120 that can be used to bias / charge the substrate support 116. The RF power supply 120 can be defined by one or more RF generators. If multiple RF generators are provided, different frequencies can be used to achieve various tuning characteristics. A bias matching circuit 118 is coupled between the RF power supply 120 and the substrate support 116. In this manner, the RF power supply 120 is connected to the substrate support 116.

[0037] The coil 134 is positioned above the window 106. The coil 134 may be made of a conductive material and include at least one full turn. Figure 1A The coil 134 shown in FIG. 1 includes at least three turns. The RF power supply 121 is configured to supply RF power to the coil 134. The matching circuit 102 is coupled between the RF power supply 121 and the coil 134. In this manner, the RF power supply 121 is connected to the coil 134. In some embodiments, an optional Faraday shield (not shown) is positioned between the coil 134 and the window 106. The Faraday shield can be maintained in a spaced relationship relative to the coil 134. The Faraday shield can be positioned immediately above the window 106. The Faraday shield can prevent metal or other substances from being deposited on the window 106 of the plasma chamber 132.

[0038] RF power is supplied from the RF power supply 121 to the coil 134, causing an RF current to flow through the coil 134. The RF current flowing through the coil 134 may generate an electromagnetic field around the coil 134. The electromagnetic field generates an induced current within the plasma chamber 132, which acts on the gas present in the plasma chamber 132 to generate plasma. Various ions and / or radicals from the plasma may interact with the substrate 112 to perform deposition or etching operations.

[0039] In some embodiments, the processing apparatus 100 optionally includes a plasma grid (not shown) that can be used to divide the plasma chamber 132 into an upper portion and a lower portion. The plasma grid can be used to limit the number of thermal electrons that enter the lower portion of the plasma chamber 132. In some embodiments, the processing apparatus 100 is designed to operate such that the plasma present in the lower portion of the plasma chamber 132 is an ion-ion plasma and the plasma present in the upper portion of the plasma chamber 132 is an electron-ion plasma.

[0040] Process gases can be introduced into the plasma chamber 132 from the top of the plasma chamber 132 via a first gas injector 104, and / or from the side of the plasma chamber 132 via a second gas injector 110. The process gases can include vaporized liquid precursors or vaporized solid precursors, which can be vaporized in a solid source vaporizer (not shown) upstream of the processing apparatus 100. One or more reactant gases can be supplied via the first gas injector 104 and / or the second gas injector 110. In some embodiments, the gas injectors 104, 110 can be replaced by showerheads. It should be understood that additional or other gas supplies can be provided to supply different gases to the plasma chamber 132 for various types of operations.

[0041] The various ways of injecting gases into the plasma chamber 132 illustrate that process gases, vaporized liquid precursors, and / or vaporized solid precursors can be provided to the plasma chamber 132 from various locations. In some embodiments, only the first gas injector 104 is used. In certain other embodiments, only the second gas injector 110 is used. In certain other embodiments, both the first gas injector 104 and the second gas injector 110 are used. In some embodiments, a manifold 122 controls which gases are supplied to each of the different gas lines. The manifold 122 enables any type of gas (reactant, carrier gas, precursor, etc.) to be provided from any of the different gas lines. In some embodiments, the carrier gas can include gases such as oxygen (O2), nitrogen (N2), and helium (He). These gases can be introduced into the plasma chamber 132 unmixed, or they can be mixed with other gases before being introduced into the plasma chamber 132.

[0042] The manifold 122 can be used to select, switch, and / or mix the outputs from the various delivery systems in the delivery system 128. In some embodiments, the delivery system 128 may include an etching gas delivery system 127 and a deposition precursor delivery system 129. The etching gas delivery system 127 can be configured to output an etching gas. Examples of etching gases include, but are not limited to, chlorine (Cl2), hydrogen bromide (HBr), and sulfur hexafluoride (SF6). The deposition precursor delivery system 129 can be configured to provide a liquid precursor that is vaporized and delivered in a vapor form during a deposition process (e.g., an ALD process). Thus, the deposition precursor can be introduced into the plasma chamber 132 and can be adsorbed on the surface of the substrate 112. The adsorbed precursor can be converted using plasma to form a film with a limited amount of adsorption. In some embodiments, the deposition precursor includes an aminosilane precursor. An exemplary deposition precursor can have a chemical composition of the following formula: C x H y N z O a Si b .

[0043] The vacuum pump system 130 is connected to the plasma chamber 132 and can be used to extract process gases from the plasma chamber 132 and maintain a certain pressure in the plasma chamber 132. A valve 126 can be placed between the exhaust portion 124 and the vacuum pump system 130 to control the amount of vacuum suction applied to the plasma chamber 132. In some embodiments, the vacuum pump system 130 can include one or two mechanical dry pumps and / or turbomolecular pumps. In some embodiments, the vacuum pump system 130 can be activated to purge the plasma chamber 132 after each deposition or etching operation is completed. An example of a vacuum pump system 130 is shown in FIG. Figure 1B The vacuum pump system 130 is fluidly connected to the plasma chamber 132 and can be used to remove etching gases, deposition precursors, and reaction byproducts from the plasma chamber 132 .

[0044] When the processing apparatus 100 is installed in a cleanroom or manufacturing facility, it can be coupled to a facility (not shown). The facility includes piping that provides process gases, vacuum, temperature control, and environmental particle control. When these facilities are installed in the target manufacturing facility, they can be coupled to the processing apparatus 100. In addition, the processing apparatus 100 can be coupled to a transfer chamber that allows a robot arm to transfer substrates into and out of the plasma chamber 132 using an automated system.

[0045] The processing device 100 may also include a system controller 108. The system controller 108 (which may include one or more physical or logical controllers) controls some or all operations of the processing device 100. The system controller 108 may include one or more memory devices and one or more processors. The processor may include a central processing unit (CPU) or computer, analog and / or digital input / output connectors, a stepper motor controller board, and other similar components. Instructions for performing appropriate control operations are executed on the processor. These instructions may be stored on a memory device associated with the system controller 108 or may be provided over a network. In some embodiments, the system controller 108 executes system control software.

[0046] The system control software may include instructions for controlling the timing and / or magnitude of application of any one or more of the following chamber operating conditions: gas mixture and / or composition, chamber pressure, chamber temperature, wafer / wafer support temperature, bias applied to the substrate (which in many embodiments may be zero), frequency and power applied to coils or other plasma generating components, substrate position, substrate movement speed, and other parameters of the specific process performed by the tool. The system control software may further control heating operations, sweep operations, and cleaning operations via the vacuum pump system 130. The system control software may be configured in any suitable manner. For example, subroutines or control objects may be written to control the operation of the necessary process tool components to perform various process tool processes. The system control software may be encoded in any suitable computer-readable programming language.

[0047] In some embodiments, the system control software includes input / output control (IOC) sequence instructions for controlling the various parameters described above. For example, each stage of a semiconductor processing process may include one or more instructions executed by the system controller 108. For example, instructions for setting process conditions for a stage may be included in a corresponding recipe stage. In some embodiments, the recipe stages may be arranged in a sequence so that the steps in the doping process are performed in a certain order for that process stage. For example, a recipe may be configured to perform an etching operation and include one or more cycles of an ALD process performed between each of the etching operations. The recipe may be configured to perform a sweep operation and / or a cleaning operation between the etching operation and one or more cycles of the ALD process.

[0048] In some embodiments, the system controller 108 is configured with instructions for performing one or more of the following: performing an etching operation on the substrate 112 in the plasma chamber 132 using one or more etching gases from the etching gas delivery system 127; and performing a deposition operation on the substrate 112 in the plasma chamber 132 using one or more deposition precursors from the deposition precursor delivery system 129. The system controller 108 may be further configured with instructions for exhausting the one or more etching gases and the one or more deposition precursors from the plasma chamber 132 using the vacuum pump system 130. The system controller 108 may be further configured with instructions for heating a pump surface of the vacuum pump system 130 to an elevated temperature. The system controller 108 may be further configured with instructions for purging the one or more etching gases or the one or more deposition precursors from the vacuum pump system 130 according to a purge time determined by residual gas analysis (RGA) or Fourier transform infrared (FTIR) gas analysis. The system controller 108 may be further configured with instructions for performing a cleaning operation using reactive gas flowing through the vacuum pump system 130 before or after the etching operation.

[0049] In some embodiments, other computer software and / or programs may be used. Examples of programs or program sections for this purpose include substrate positioning programs, process gas composition control programs, pressure control programs, heater control programs, and RF power supply control programs.

[0050] In some cases, the system controller 108 controls gas concentrations, substrate movement, and / or power supplied to the coils 134 and / or substrate support 116. The system controller 108 can control gas concentrations by, for example, opening and closing associated valves to generate one or more inlet gas flows that provide the necessary reactants at appropriate concentrations. Substrate movement can be controlled by, for example, instructing a substrate positioning system to move as required. Power supplied to the coils 134 and / or substrate support 116 can be controlled to provide a specific RF power level. If a grid is used, the RF power can be adjusted by the system controller 108 to generate an electron-ion plasma in the upper portion of the plasma chamber 132 and an ion-ion plasma in the lower portion of the plasma chamber 132. Furthermore, the system controller 108 can be configured to supply power to the substrate support 116 under conditions such that an electron-ion plasma does not form in the lower portion of the plasma chamber 132.

[0051] The system controller 108 may control these and other aspects based on sensor outputs (e.g., when power, potential, pressure, gas level, etc. reaches a certain threshold), timing of operations (e.g., opening valves, purging, etc. at certain times in the process), or based on instructions received from a user.

[0052] In some embodiments, the system controller 108 is part of a system, which may be part of the examples described above. Such a system may include semiconductor processing equipment, including one or more processing tools, one or more chambers, one or more workstations for processing, and / or specific processing components (wafer pedestals, gas flow systems, etc.). These systems may be integrated with electronic devices to control their operation before, during, and after processing of semiconductor wafers or substrates. These electronic devices may be referred to as "controllers," which may control various components or subassemblies of one or more systems. Depending on the requirements of the process and / or the type of system, the system controller 108 can be programmed to control any of the processes disclosed herein, including the delivery of etching gases and deposition precursors into the plasma chamber 132, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, RF generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, position and operation settings, wafer transport in and out of the tool, purging of gases and byproducts from the plasma chamber 132, purging of gases and byproducts from the vacuum pump system 130, heating of component surfaces of the vacuum pump system 130, and purging of the vacuum pump system 130 with reactive gases.

[0053] Broadly speaking, the system controller 108 can be defined as an electronic device having various integrated circuits, logic, memory, and / or software that receive instructions, send instructions, control operations, enable cleaning operations, enable endpoint measurements, and the like. The integrated circuits can include a chip in the form of hardware that stores program instructions, a digital signal processor (DSP), a chip defined as an application specific integrated circuit (ASIC), and / or one or more microprocessors or microcontrollers that execute program instructions (e.g., software). The program instructions can be instructions transmitted to the system controller 108 in the form of various individual settings (or program files) that define operating parameters for performing a particular process on a semiconductor wafer, for a semiconductor substrate, or for the system. In some embodiments, these operating parameters can be part of a recipe defined by a process engineer for completing one or more process steps during the fabrication of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of a substrate.

[0054] In some embodiments, the system controller 108 may be part of or coupled to a computer that is integrated with the system, coupled to the system, connected to the system via a network, or a combination thereof. For example, the system controller 108 may be located in the "cloud" or may be all or part of a main fab computer system that allows remote access to substrate processing. The computer enables remote access to the system to monitor the current progress of manufacturing operations, view the history of past manufacturing operations, view trends or performance metrics from multiple manufacturing operations, change parameters of the current process, set processing steps to continue the current process, or start a new process. In some examples, a remote computer (e.g., a server) can provide process recipes to the system via a network, which may include a local area network or the Internet. The remote computer may include a user interface that enables the input or programming of parameters and / or settings, which are then transmitted from the remote computer to the system. In some examples, the system controller 108 receives instructions in the form of data that specify parameters for each of the processing steps to be performed during one or more operations. It will be appreciated that these parameters may be specific to the type of process to be performed, as well as the type of tool with which the system controller 108 is configured to interface or control. Thus, as described above, the system controller 108 may be distributed, for example by including one or more separate controllers that are networked together and work toward a common goal, such as the processing and control described herein. An example of a distributed system controller 108 for such purposes may be one or more integrated circuits on a chamber that communicate with one or more integrated circuits located remotely (e.g., at the platform level, or as part of a remote computer), which in combination control the processing on the chamber.

[0055] As described above, depending on one or more processing steps to be performed by the tool, the system controller 108 may communicate with one or more of the following in the semiconductor fabrication facility: other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools throughout the facility, a host computer, another system controller 108, or tools used in material transport to transport substrate containers to and from tool locations and / or load ports. Vacuum pump system

[0056] According to some embodiments, Figure 1B FIG1 is a schematic diagram of an exemplary vacuum pump system including a roughing pump, wherein the roughing pump is used in series with a turbomolecular pump. However, it should be understood that the vacuum pump system 130 of the present invention may include a vacuum pump system 130 having a roughing pump connected to a turbomolecular pump. Figure 1BThe vacuum pump system 130 is in fluid communication with a process chamber 132 (such as the plasma chamber described above). The vacuum pump system 130 can control the chamber pressure in the process chamber 132. The vacuum pump system 130 can remove byproducts, unreacted deposition precursors, and unreacted etching gases from the process chamber 132. The vacuum pump system 130 can include multiple pumps that operate within a range of varying pressures. Figure 1B As shown in FIG, the vacuum pump system 130 includes a turbomolecular pump 140 and a roughing pump 150, wherein the roughing pump 150 is configured to generate a "rough" vacuum and the turbomolecular pump 140 is configured to follow to generate a very high vacuum. For example, the turbomolecular pump 140 can be configured to generate a vacuum pressure in the process chamber 132 in a very high range (e.g., between about 1 mTorr and about 1 Torr), while the roughing pump 150 can be configured to generate a vacuum pressure in the process chamber 132 in a relatively low range (e.g., between about 1 Torr and atmospheric pressure). The roughing pump 150 can also be referred to as a "pre-pump" or "primary pump." For example, the roughing pump 150 can include one or two mechanical dry pumps.

[0057] The roughing pump 150 can be positioned downstream of the turbomolecular pump 140. In some embodiments, a booster pump 160 is optionally disposed between the turbomolecular pump 140 and the roughing pump 150, wherein the booster pump 160 can generate a vacuum pressure within a range between the turbomolecular pump 140 and the roughing pump 150. In some embodiments, the booster pump 160 can be considered part of the roughing pump 150 of the vacuum pump system 130. In some embodiments, the booster pump 160 can be considered separate from the roughing pump system. In some embodiments, the booster pump 160 comprises a blower such as a Roots-type blower. The roughing pump 150 and / or the booster pump 160 can be connected in series with the turbomolecular pump 140 to operate the chamber pressure within a large vacuum pressure range.

[0058] A first valve 152 may be disposed between the turbomolecular pump 140 and the roughing pump 150. The first valve 152 may be controlled to discharge the process gas from the turbomolecular pump 140 to the roughing pump 150. A second valve 154 may be disposed between an exhaust port 162 and the roughing pump 150, wherein the exhaust port 162 is connected to the process chamber 132. The second valve 154 may be controlled to discharge the process gas to a foreline 164 through the exhaust port 162. The foreline 164 connects the roughing pump 150 to the exhaust port 162. Split pump or multi-inlet pump

[0059] By shunting the etching gas and the deposition precursor to separate pumps, mixing of the etching gas and the deposition precursor in the pump can be avoided. Therefore, accumulation of deposition byproducts in any separated pump is avoided or limited. In some embodiments, the vacuum pump system can be designed to have at least two separate roughing pumps. In some embodiments, each of the at least two roughing pumps can include a booster pump or a blower. In some embodiments, each of the at least two roughing pumps can include a rotor assembly, such as a rotating blade. As described below, the vacuum pump system can be operated according to a "complete shunt" scheme or a "bypass shunt" scheme.

[0060] Figure 2A FIG. 2 is a schematic diagram of an exemplary processing apparatus according to some embodiments, comprising a "completely split" vacuum pump system 230a having two separate pumps. In some embodiments, the two separate pumps are two separate roughing pumps. Figure 1A and 1B The etching gas and deposition precursor can be discharged through an exhaust port. The etching gas and deposition precursor can flow through a pipeline, such as the foreline 214. A valve 224 can be arranged between the foreline 214 and the two separate pumps. Valve 224 serves as a switchable valve. When the processing chamber 212 is performing an etching operation, valve 224 is switched to direct the etching gas through the first roughing pump 220a. When the processing chamber 212 is performing a deposition operation, valve 224 is switched to direct the deposition precursor through the second roughing pump 220b. Separating the flow of the etching gas and deposition precursor between the separate roughing pumps avoids the accumulation of deposition products caused by mixing the etching gas and the deposition gas. In some embodiments, the etching gas comprises hydrogen bromide, and the deposition precursor comprises an aminosilane precursor. In some embodiments, when the etching gas comprises hydrogen bromide, valve 224 can be switched to direct the etching gas through the first roughing pump 220a. A first roughing pump 220a and a second roughing pump 220b are disposed downstream of the foreline 214. A removal line 216 can be connected to the first roughing pump 220a and the second roughing pump 220b and disposed downstream of the first roughing pump 220a and the second roughing pump 220b to remove etching gases and deposition precursors from the vacuum pump system 230a. A purge operation can be performed between etching and deposition operations, wherein the purge time can be sufficient to completely remove the etching gases and deposition precursors from the foreline 214. Techniques for determining a sufficient purge time are described below.

[0061] The introduced etching gas and the introduced deposition gas can enter the processing chamber 212 via different gas lines. The etching gas can be provided from an etching gas delivery source, and the deposition gas can be provided from a deposition precursor delivery source. In some embodiments, some of the deposition gas from the deposition precursor delivery source can be diverted via a shunt line 218 and discharged directly to the second roughing pump 220b. The diverted deposition gas does not enter the processing chamber 212. The shunt line 218 can be fluidically coupled to the deposition precursor delivery system, and the shunt line 218 is configured to direct unused deposition precursors in the deposition cycle to the second roughing pump 220b. The deposition cycle can be an ALD cycle. Generally, ALD is a deposition technique that uses a surface self-limiting deposition reaction to deposit films layer by layer. Each ALD cycle includes a sequence of batching and conversion stages. In some embodiments, the ALD cycle includes a sequence of batching, sweeping, conversion, and sweeping stages. The dosing phase involves the delivery and adsorption of precursor materials onto the substrate surface in the processing chamber, while the conversion phase involves converting the adsorbed precursor materials into adsorption-limited amounts of deposition materials (e.g., passivation materials). The conversion phase generally involves the delivery of reactant species, such as oxidizing species (e.g., O2), to convert the adsorbed precursor materials. During the conversion phase of the ALD cycle, deposition gas may continue to flow from the deposition precursor delivery source. However, some deposition gas flowing from the deposition precursor delivery source may be diverted during the conversion phase of the ALD cycle. This diverted deposition gas does not mix with the etching gas in the processing chamber or in any of the roughing pumps.

[0062] Figure 2B is a schematic diagram of an exemplary processing apparatus according to some embodiments, the processing apparatus including a "bypass" vacuum pump system 230b having two separate pumps. Figure 1A and 1B232 . The etching gas and deposition precursor can be discharged through the exhaust port. The etching gas and deposition precursor can flow through a conduit, such as the foreline 234. The etching gas and deposition precursor flow through the first roughing pump 240a without including a valve for switching between the etching gas and the deposition precursor. However, some deposition gas can be diverted to the second roughing pump 240b via the shunt line 238. This deposition gas does not participate in the deposition operation occurring in the processing chamber 232. Specifically, the deposition gas during the conversion phase of the ALD cycle is diverted to the second roughing pump 240b via the shunt line. In other words, the unused deposition precursor in the ALD cycle flows out of the deposition precursor delivery system and flows directly through the second roughing pump 240b without entering the processing chamber 232. Thus, the deposition precursor during the dosing phase of the ALD cycle passes through the first roughing pump 240a and mixes with the etching gas, while the deposition precursor during the conversion phase of the ALD cycle passes through the second roughing pump 240b and does not mix with the etching gas. Although some deposition gas mixes with the etching gas in the first roughing pump 240a, the amount of mixing is significantly reduced, resulting in significantly reduced accumulation of deposition byproducts. In addition, the second roughing pump 240b is not in fluid communication with the processing chamber 232, so the second roughing pump 240b can be shared among multiple modules / equipment. Multiple shunt lines from other modules / equipment (not shown) can shunt unused deposition precursors in the ALD cycle through the second roughing pump 240b.

[0063] Figure 2C Schematic diagram of an exemplary processing apparatus according to some embodiments, the processing apparatus includes a "multi-inlet" vacuum pump system 230c operating in different stages. Rather than having separate pumps for receiving etching and deposition gases, the vacuum pump system 230c may have a pump with multiple inlets. The process gas exhausted from the processing chamber may include etching and deposition gases. One of the multiple inlets may be opened to receive the process gas from the processing chamber based on the operating pressure of the pump. For example, the first inlet 252 may be opened to receive the process gas during the low pressure stage 254, and the second inlet 262 may be opened to receive the process gas during the high pressure stage 264. Figure 2CIn the embodiment of the present invention, the pump may include a roughing pump (not shown). The roughing pump may or may not include a booster pump (or blower). When the roughing pump operates in the low pressure range, the first exhaust port 256 coupled to the first inlet 252 may be opened to discharge the process gas from the process chamber (not shown). When the roughing pump operates in the high pressure range, the second exhaust port 266 coupled to the second inlet 262 may be opened to discharge the process gas from the process chamber. In some embodiments, the high pressure range is between about 1 Torr and about 10 Torr or between about 0.5 Torr and about 5 Torr, while the low pressure range is between about 0.5 Torr and about 3 Torr or between about 0.1 Torr and about 1 Torr. In some embodiments, the deposition gas is typically discharged from the process chamber during the high pressure range, while the etching gas is typically discharged from the process chamber during the low pressure range. In particular, ALD processes tend to operate in the high pressure range.

[0064] Accumulation of deposition byproducts in the roughing pump may be affected by pressure and / or temperature. Components operating within the low-pressure phase 254 may be unheated, while components operating within the high-pressure phase 264 may be heated. To prevent accumulation of deposition byproducts during the high-pressure phase 264, the pump components may be heated to an elevated temperature sufficient to prevent byproduct accumulation. In some embodiments, higher pressures require higher temperatures to prevent byproduct accumulation. In some embodiments, the elevated temperature is equal to or greater than approximately 160°C, between approximately 80°C and approximately 500°C, between approximately 100°C and approximately 400°C, between approximately 120°C and approximately 300°C, or between approximately 150°C and approximately 250°C. Without being limited by theory, mixing between the deposition precursor and the etching gas is more likely to occur during the high-pressure phase of the pump, while mixing between the deposition precursor and the etching gas is less likely to occur during the low-pressure phase of the pump. Therefore, heating the pump components to an elevated temperature during the high-pressure phase can avoid or minimize the accumulation of deposition byproducts. The aspect of heating the pump components in the pump is described in more detail below.

[0065] In some embodiments, the pump assembly operating within the low pressure stage 254 may be susceptible to accumulation of deposited byproducts. This is in addition to the pump assembly operating within the high pressure stage 264. In some embodiments, the blower assembly may be separate from the rotor assembly of the vacuum pump system 230c. The blower assembly may be part of the boost pump of the roughing pump. In some embodiments, the blower assembly may operate during the low pressure stage 254 of the roughing pump, while the rotor assembly may operate during the high pressure stage 264 of the roughing pump. In some embodiments, the blower assembly and the rotor assembly may be heated to an elevated temperature sufficient to prevent accumulation of byproducts. Such an assembly is shown in FIG. Figure 3 middle. Surface coating

[0066] The vacuum pump system (including the roughing pump and its components) can be coated with one or more materials to limit surface reactions that would otherwise cause deposition byproducts to accumulate in the vacuum pump system. The various pump components of the pump may include, but are not limited to, a rotor assembly, a stator assembly, an inlet, bearings, a shaft, and a transmission gear. Additional pump components may also include a booster pump and a blower, which may be provided as separate units or integrated with the pump. The rotor assembly may include, for example, rotating blades on counter-rotating shafts. The transmission gear transfers torque to the shaft and causes the rotating blades to rotate in opposite directions and engage with each other. The stator assembly may include, for example, a housing for surrounding the rotor assembly. One or more inlets may receive etching gases and deposition precursors discharged from the processing chamber, wherein the one or more inlets may be coupled to the stator assembly. The one or more inlets may be connected to a channel leading to the rotor assembly. The bearings may support various components of the pump, such as a shaft.

[0067] In some embodiments, the pump assembly of the pump in the vacuum pump system is made of a metal material (e.g., iron). For example, the pump assembly can be made of cast iron. However, the pump assembly made of cast iron or other metal materials may be susceptible to corrosion and / or accumulation of deposition byproducts. In some embodiments, the surface of the pump assembly can be coated with one or more materials that are resistant to corrosion and / or accumulation of deposition byproducts. Thus, the surface coating on the surface of the pump assembly can eliminate or at least reduce surface reactions that would otherwise cause accumulation of deposition byproducts.

[0068] Exemplary materials for the surface coating may include, but are not limited to, plated nickel, plated cobalt, titanium nitride (TiN), Inconel, Hastelloy, ceramic materials, fluoropolymers, and combinations thereof. Such materials may be corrosion-resistant. The surface of at least one of the pump's inlet and rotor assembly may be coated with the surface coating to protect the pump's rotor assembly and inlet from degradation due to accumulation of deposited byproducts. Other surfaces of the pump components, including bearings, shafts, etc., may also be coated with the surface coating.

[0069] In some embodiments, the pump components of a pump in a vacuum pump system are made of a ceramic material, such as aluminum oxide (Al2O3). Rather than being coated with metallic materials, the pump components can be made of a material that is resistant to corrosion and / or accumulation of deposition byproducts. Thus, these pump components can eliminate or at least reduce surface reactions that would otherwise lead to accumulation of deposition byproducts.

[0070] In some embodiments, the pump components can be heated to further eliminate or reduce surface reactions that lead to the accumulation of deposition byproducts. Certain pump components can be heated to elevated temperatures (e.g., a temperature of at least about 160° C.) to avoid or reduce the accumulation of deposition byproducts. For example, one or more shafts can be connected to and support one or more rotor assemblies, wherein each of the shafts can be connected to a heat source for heating the surface of the one or more rotor assemblies. Examples of heat sources can include, but are not limited to, electrical wires, heat lamps, and thermal fluids.

[0071] It should be understood that the embodiments using the aforementioned materials to limit surface reactions can be combined with one or more of the aforementioned embodiments for preventing accumulation of deposition byproducts. It should also be understood that the embodiments using the aforementioned materials to limit surface reactions can be combined with one or more of the embodiments described below for preventing accumulation of deposition byproducts. Pump heating

[0072] There is a challenge in spatially heating all surfaces of various pump components to a sufficiently hot temperature to avoid accumulation of deposition byproducts. Improvements in the thermal design of pumps (e.g., roughing pumps) can keep the surfaces of the pump components sufficiently hot to avoid accumulation of deposition byproducts. Aspects of the present invention provide a method for exhausting an etching gas and a deposition precursor using a vacuum pump system, and heating the surfaces of the pump components of the vacuum pump system to an elevated temperature. The elevated temperature is sufficiently hot to avoid accumulation of deposition byproducts caused by reactions between the etching gas and the deposition precursor. For example, the elevated temperature may be equal to or greater than approximately 160°C, between approximately 80°C and approximately 500°C, between approximately 100°C and approximately 400°C, between approximately 120°C and approximately 300°C, or between approximately 150°C and approximately 250°C. The elevated temperature can be maintained while exhausting the etching gas and deposition precursor. The etching gas may comprise hydrogen bromide, and the deposition precursor may comprise an aminosilane precursor.

[0073] In some embodiments, heating the surfaces of the pump components of the pump can be achieved by circulating a hot fluid or heated purge gas through the pump. A reservoir of hot fluid or heated purge gas can be provided external to the vacuum pump system, and the vacuum pump system can draw from this reservoir to heat its pump components. In some embodiments, heating the surfaces of the pump components includes heating one or more shafts connected to and supporting one or more rotor assemblies in the pump. In some embodiments, each shaft may include a channel for accommodating a heat source, wherein the heat source includes electrical wires, a heat lamp, a hot fluid, or a combination thereof. The channel allows thermal energy to be conducted through the shaft and transferred to the surrounding surface by radiation and / or conduction. Thus, the surface of one or more rotor assemblies can be heated to a temperature of at least 160°C, between about 80°C and about 500°C, between about 100°C and about 400°C, between about 120°C and about 300°C, or between about 150°C and about 250°C.

[0074] Figure 3 is an example of a rotor assembly in a vacuum pump system 300 according to some embodiments. Deposition precursors and etching gases are exhausted from a processing chamber and enter the vacuum pump system 300, which has a stator assembly 310 surrounding a first rotor assembly 322 and a second rotor assembly 324. The deposition precursors and etching gases pass through a channel 312 in the stator assembly 310. The first rotor assembly 322 and the second rotor assembly 324 can rotate in opposite directions to push the gases through the vacuum pump system 300. A first shaft 332 can be connected to and support the first rotor assembly 322, and a second shaft 334 can be connected to and support the second rotor assembly 324. In some embodiments, each shaft 332, 334 can be hollow or provide a channel or opening through which electrical wires, a heat lamp, a hot fluid, or other heat source can pass. In some embodiments, each shaft 332, 334 can include an outer insulating material and an inner conductive material. The shafts 332, 334 can be configured to rotate in counter-rotating directions.

[0075] It should be understood that the embodiment using pump heating can be combined with one or more of the aforementioned embodiments for preventing the accumulation of deposition byproducts (including embodiments involving separate pumps, separate inlets, and surface coatings). It should also be understood that the embodiment using pump heating can be combined with one or more of the embodiments described below for preventing the accumulation of deposition byproducts. Pump cleaning

[0076] A sweep operation may be performed between deposition and etching operations to more thoroughly purge deposition precursors, etching gases, and / or deposition by-products from the vacuum pump system. The duration of the sweep operation may be determined to be long enough so that no deposition precursors, etching gases, and deposition by-products are detected in the vacuum pump system. In this way, deposition precursors and etching gases do not have a chance to mix together and cause accumulation of deposition by-products. One or more sensors in the vacuum pump system may be utilized to perform this determination. For example, residual gas analysis (RGA), Fourier transform infrared (FTIR) gas analysis, or other suitable gas analysis may be utilized to measure the sweep time for purging deposition precursors, etching gases, and deposition by-products from the vacuum pump system. In some embodiments, the etching gas comprises hydrogen bromide, and the deposition precursor comprises an aminosilane precursor.

[0077] A method for purging a pump (e.g., a roughing pump) may include performing a purge operation in a processing chamber between etching and deposition operations. One method may include: performing an etching operation on a wafer in a processing chamber, wherein one or more etching gases are exhausted by a pump in fluid communication with the processing chamber; and purging the one or more etching gases from the pump according to a first predetermined duration. The method may also include: performing a deposition operation on the wafer in the processing chamber, wherein one or more deposition precursors are exhausted by the pump; and purging the one or more deposition precursors from the pump according to a second predetermined duration. In some embodiments, the first predetermined duration and the second predetermined duration may be determined by RGA, FTIR gas analysis, or other suitable gas analysis. For example, RGA, FTIR gas analysis, or other suitable gas analysis may utilize a sensor to measure when etching gas and / or deposition precursors are no longer present in the gas line of the vacuum pump system, thereby serving as an endpoint detection system. Thus, the gas analysis can determine an appropriate purge time to remove the etching gas or deposition precursor from the vacuum pump system.

[0078] A method for determining a purge time for purging a pump may include performing a purge operation between etching and deposition operations in a processing chamber and measuring a purge time during the purge operation. The method may include: performing an etching operation on a wafer in the processing chamber, wherein one or more etching gases are exhausted by a pump in fluid communication with the processing chamber; purging the one or more etching gases from the pump; and measuring a first purge time for purging the one or more etching gases. The method may also include: performing a deposition operation on a wafer in the processing chamber, wherein one or more deposition precursors are exhausted by the pump; purging the one or more deposition precursors from the pump; and measuring a second purge time for purging the one or more deposition precursors. The purge time may be measured using RGA, FTIR gas analysis, or other suitable gas analysis. Future purge operations performed in the processing chamber may utilize the purge time measured by the gas analysis, ensuring that the purge time is long enough to completely or at least substantially purge the deposition precursors and etching gases from the vacuum pump system.

[0079] Longer purge times and more accurately measured purge times can avoid unwanted mixing of deposition precursors and etching gases in the vacuum pump system. Embodiments using longer purge times and more accurately measured purge times can be combined with one or more of the aforementioned embodiments for preventing accumulation of deposition byproducts (including embodiments involving separate pumps, separate inlets, surface coatings, and pump heating). For example, RGA or FTIR gas analysis can be used to determine when to switch valves to divert etching gases through the first roughing pump and when to switch valves to divert deposition precursors through the second roughing pump. It should be understood that embodiments using longer purge times and more accurately measured purge times can be combined with one or more of the embodiments described below for preventing accumulation of deposition byproducts. Pump cleaning

[0080] A cleaning operation may be performed between deposition and etching operations, after a deposition or etching operation is completed, or after a certain number of wafers have been processed in a processing chamber. A cleaning operation may be performed to clean the vacuum pump system to prevent mixing of deposition precursors with etching gases or to remove deposition byproducts from the vacuum pump system. In some embodiments, the deposition precursor may include an aminosilane precursor, and the etching gas may include hydrogen bromide. The execution of the cleaning operation includes flowing a reactive gas through a vacuum pump system, wherein the vacuum pump system includes one or more pumps in fluid communication with the processing chamber. The one or more pumps may include a roughing pump. In some embodiments, the one or more pumps may also include a booster pump and / or a turbomolecular pump. In some embodiments, the reactive gas is flowed through the processing chamber and through one or more pumps of the vacuum pump system. In some embodiments, the reactive gas includes free radicals and / or ions generated in situ in the processing chamber, generated in a remote plasma source, or generated by a plasma source installed in a foreline connected to one or more pumps of the vacuum pump system.

[0081] The cleaning operation generally involves cleaning chemicals that effectively remove deposition precursors, etching gases, and deposition byproducts. In some embodiments, the cleaning operation can be part of a waferless automated clean (WAC) operation, but it should be understood that the cleaning operation can be performed with or without a wafer in the process chamber. The cleaning chemical can include reactive gases, such as fluorine-containing species, chlorine-containing species, bromine-containing species, iodine-containing species, oxygen-containing species, or combinations thereof.

[0082] Figure 4 A flow chart of an exemplary method of a cleaning process to prevent accumulation of deposition byproducts in a vacuum pump system according to some embodiments. Figure 4 The cleaning process 400 shown in FIG. 4 may be performed using fewer, additional, or different operations.

[0083] At block 410 of the cleaning process 400, one or more deposition operations are performed in the process chamber. The one or more deposition operations may utilize one or more deposition precursors to deposit material on the wafer. In some embodiments, the one or more deposition operations may utilize one or more deposition precursors from an ALD cycle. The one or more deposition precursors may include an aminosilane precursor. The one or more deposition precursors may be exhausted to one or more pumps of a vacuum pump system, wherein the one or more pumps are in fluid communication with the process chamber. The one or more pumps may include a roughing pump.

[0084] At block 420 of the cleaning process 400, one or more etching operations are performed in the process chamber. The one or more etching operations may utilize one or more etching gases to etch material from the wafer. The one or more etching gases may include hydrogen bromide. The one or more etching gases may be exhausted to one or more pumps of the vacuum pump system. Figure 4As shown in , in some embodiments, the one or more etching operations may be performed before the cleaning operation of block 430. Alternatively, the one or more etching operations may be performed after the cleaning operation of block 430. This is shown in Figure 4 In other words, the cleaning operation can be performed between deposition and etching operations while processing the wafer, or the cleaning operation can be performed after deposition and etching operations are completed while processing the wafer.

[0085] At block 430, a cleaning operation is performed using a reactive gas flowing through a vacuum pump system in fluid communication with the process chamber. In some embodiments, one or more deposition operations of block 410, one or more etching operations of block 420 or block 440, and the cleaning operation of block 430 can be performed with a wafer in the process chamber. In some embodiments, the cleaning operation of block 430 can be performed without a wafer in the process chamber.

[0086] In some embodiments, the reactive gas may include fluorine-containing species, such as nitrogen trifluoride (NF3), carbon tetrafluoride (CF4), xenon difluoride (XeF2), sulfur hexafluoride (SF6), and chlorine trifluoride (ClF3). In some embodiments, the reactive gas may include oxygen-containing species, such as oxygen (O2) and ozone (O3). In some embodiments, the reactive gas may include chlorine-containing species, such as chlorine (Cl2). The reactive gas may remove deposition precursors or etching precursors from the vacuum pump system, or may remove deposition byproducts formed in the vacuum pump system.

[0087] In some embodiments, the reactive gas may contain free radicals and / or ions of fluorine, chlorine, oxygen, or a combination thereof. The free radicals and / or ions of fluorine may contain F * and F2 + , chlorine radicals and / or ions may include Cl * 、Cl - , and Cl + , and the oxygen radicals and / or ions may include O* and O2 - Generally speaking, fluorine, chlorine, and oxygen radicals are more likely to travel through one or more pumps of a vacuum pumping system without recombination than fluorine, chlorine, and oxygen ions. The reactive gas can remove deposition precursors or etching precursors from the vacuum pumping system or can remove deposition byproducts formed in the vacuum pumping system.

[0088] In some embodiments of cleaning process 400, cleaning process 400 further comprises generating a reactive gas, wherein the reactive gas comprises a plasma-activated species of fluorine, chlorine, oxygen, or a combination thereof. The plasma-activated species may comprise free radicals and / or ions of fluorine, chlorine, oxygen, or a combination thereof, as described above. Various plasma sources may be used to generate the plasma-activated species for performing the cleaning operation of block 430. In some embodiments, the plasma-activated species may be generated in situ within the processing chamber via a plasma reaction. For example, a fluorine-containing gas, a chlorine-containing gas, an oxygen-containing gas, or a combination / sequence thereof may be introduced into the processing chamber, and a plasma may be ignited to form the plasma-activated species of the fluorine-containing gas, the chlorine-containing gas, the oxygen-containing gas, or a combination / sequence thereof. The plasma-activated species may flow from the processing chamber and through one or more pumps of a vacuum pumping system to prevent accumulation of deposition byproducts. In some embodiments, the plasma-activated species may be generated in a plasma source located in a foreline, wherein the foreline provides an interconnection between the one or more pumps and the processing chamber. In this manner, the plasma-activated species may be generated near the one or more pumps, limiting the possibility of recombination before reaching the one or more pumps. For example, a Litmas pump may be installed in the foreline near the one or more pumps. TM A plasma source is provided to generate a plasma-activated species of a gas comprising fluorine, chlorine, oxygen, or a combination / sequence thereof. In some embodiments, the plasma-activated species can be generated in a remote plasma source located external to the foreline. The remote plasma source can be positioned upstream of the foreline. The plasma-activated species can be generated in the remote plasma source and injected into the foreline to pass through the one or more pumps.

[0089] In some embodiments of the cleaning process 400, during the cleaning operation of block 430, ozone (O3) may be flowed to one or more pumps of the vacuum pumping system. Ozone generally has a longer lifespan than ions and / or radicals of oxygen. Therefore, ozone is more likely to reach the one or more pumps of the vacuum pumping system without recombining. In some embodiments, ozone may be provided in the processing chamber and discharged to the vacuum pumping system. In some embodiments, ozone may be generated by a separation unit that introduces ozone into the foreline leading to the one or more pumps. For example, such a separation unit for generating ozone may be installed in the foreline or in the area between the processing chamber and the foreline. Compared to plasma-activated species of oxygen provided by a remote plasma source or provided in situ in the processing chamber, ozone provided by the separation unit or provided in the processing chamber may have a better chance of reaching the one or more pumps.

[0090] Ozone flowing to one or more pumps of the vacuum pumping system can react with substances in the pumping equipment to form oxidized products. For example, ozone can transport oxidizing free radicals that form bromine oxide (BrO), silicon dioxide (SiO2), chlorine oxide (ClO), or a combination thereof. After flowing ozone to the one or more pumps of the vacuum pumping system, a fluorine-containing substance can be flowed to the one or more pumps. The fluorine-containing substance can include fluorine radicals and / or ions, wherein the fluorine-containing substance can originate from the processing chamber or from a remote plasma source. The oxidized products can be etched away by the fluorine-containing substance. Without being limited by any theory, the fluorine-containing substance can cause the oxidized products to become volatile. The volatilized products can be discharged to an abatement device.

[0091] In some embodiments, the cleaning operation of block 430 includes flowing ozone and then flowing a fluorine-containing substance through a vacuum pump system to remove or prevent accumulation of deposition byproducts. The ozone treatment as a cleaning operation can be performed simultaneously during wafer processing or in an interval after wafer processing. In one example, such ozone treatment can be performed simultaneously with the execution of one or more deposition operations of block 410 or one or more etching operations of block 420. For example, ozone can be flowed simultaneously with the flow of etching gas in the processing chamber. In another example, such ozone treatment can be performed between one or more deposition operations of block 410 and one or more etching operations of block 420. This can cause the deposition precursor to be immediately oxidized. In yet another example, such ozone treatment can be performed in an interval after one or more deposition operations of block 410 and one or more etching operations of block 420.

[0092] The cleaning chemicals used in the cleaning operation can prevent the accumulation of deposition byproducts in the vacuum pump system. Embodiments using such cleaning chemicals can be combined with one or more of the aforementioned embodiments for preventing the accumulation of deposition byproducts, including embodiments involving separate pumps, separate inlets, surface coatings, pump heating, and longer and more accurately measured purge times. For example, a reactive gas can be flowed through one or more pumps during the cleaning operation while the surfaces of the pump components are heated to an elevated temperature, wherein the elevated temperature is equal to or greater than about 160°C, between about 80°C and about 500°C, between about 100°C and about 400°C, between about 120°C and about 300°C, or between about 150°C and about 250°C. Gas injectors

[0093] Deposition precursor and etching gas can be discharged from the processing chamber by the roughing pump of vacuum pump system. The mixing of deposition precursor and etching gas may cause unwanted deposition in the roughing pump, which may damage the pumping equipment. Specifically, deposition precursor and etching gas may react with the components in the vacuum pump system to form by-products, which may cause vacuum pump system failure. Although purge gas (e.g., N2) can be used to exhaust the roughing pump, unwanted deposition may still occur in the roughing pump (especially on the moving parts of the roughing pump). For example, unwanted deposition may occur at the back section of the roughing pump or at the outlet of the roughing pump.

[0094] Without being bound by any theory, a high pressure point may exist at the outlet of the roughing pump, wherein such a high pressure point is typically adjacent to the rear section of the roughing pump. Exhaust gas is discharged from the roughing pump and may be exhausted to atmospheric pressure or near atmospheric pressure. As used herein, "near atmospheric" pressure is a pressure that is within 10% of atmospheric pressure (i.e., 760 Torr). Due to this high pressure point at the outlet (e.g., exhaust port) of the roughing pump, this may cause stagnation of exhaust gas at the outlet of the roughing pump. This may cause the deposition precursor and etching gas to remain at the outlet of the roughing pump for a relatively long period of time. The deposition precursor and etching gas may remain long enough to mix and cause unwanted deposition. In addition, without being bound by any particular theory, higher gas pressures at various stages of the vacuum pump system can significantly increase the reaction rate. Specifically, higher pressure conditions can accelerate the reaction between the deposition precursor (e.g., aminosilane) and the etching gas (e.g., hydrogen bromide), while lower pressure conditions can slow down the reaction between the deposition precursor and the etching gas.

[0095] Figure 5Schematic diagram of an exemplary vacuum pump system 500 including a roughing pump 510 having an outlet 512 in fluid communication with an abatement assembly 514. The vacuum pump system 500 includes the roughing pump 510. In some embodiments, the roughing pump 510 may be used in combination with, or may optionally include, an optional booster pump 520. Deposition precursors and etching gases may be exhausted from a processing chamber (not shown) via the roughing pump 510. The roughing pump 510 may include one or more moving parts, wherein the one or more moving parts may include a rotor assembly. In some embodiments, a purge gas 530 (e.g., N2) may be provided to flow through the roughing pump 510 to exhaust the deposition precursors and etching gases from the roughing pump 510. The exhausted deposition precursors and etching gases may exit the roughing pump 510 at an outlet 512 of the roughing pump 510. The outlet 512 of the roughing pump 510 may be an exhaust port. In some embodiments, the exhausted deposition precursors and etching gases may be exhausted to an abatement assembly 514 for processing. A line 516 comprising pipes and tubing may connect the outlet 512 of the roughing pump 510 to the abatement assembly 514. The exhausted deposition precursors and etching gases may be exhausted at the outlet 512 of the roughing pump 510 at an exhaust pressure of approximately 760 Torr. During operation, one or more stages of the roughing pump 510 may be at a pressure below atmospheric pressure (e.g., below 760 Torr) or low pressure. During operation, the line 516 between the abatement assembly 514 and the roughing pump 510 may be at atmospheric pressure (i.e., approximately 760 Torr). Even if additional dilution gas 540 (e.g., N2) is provided at the outlet 512 of the roughing pump 510, any pressure drop may be negligible to effectively exhaust the gases from the outlet 512 of the roughing pump 510 and prevent unwanted deposition. The dilution gas 540 is used to dilute the exhaust gas, and the pipeline 516 between the roughing pump 510 and the abatement assembly 514 is only under a low amount of vacuum suction, which may be several Torr below atmospheric pressure.

[0096] As described above, the high pressure at the outlet 512 of the roughing pump 510 may cause stagnation and retention of exhaust gases, and may increase the reaction rate of the formation of unwanted byproducts. The unwanted byproducts may form on one or more moving parts of the roughing pump 510, including on any of the one or more moving parts adjacent to the outlet 512 of the roughing pump 510. This may cause one or more moving parts to stick and cause malfunction / damage to the vacuum pump system 500.

[0097] In the present disclosure, one or more gas ejectors may be provided at the outlet of the roughing pump, from which gas is discharged. The one or more gas ejectors may be configured to reduce the pressure at the outlet of the roughing pump, wherein the one or more gas ejectors may be connected in series with the roughing pump and located downstream of the roughing pump. The one or more gas ejectors near the outlet of the roughing pump are used to reduce the discharge pressure of the roughing pump. The one or more gas ejectors generate suction to effectively discharge the exhaust gas from the outlet of the roughing pump, thereby reducing the discharge pressure at the roughing pump.

[0098] A gas ejector is a pump that uses high-pressure gas to entrain and compress other gases. A gas ejector produces a high-speed jet stream that entrains a low-pressure stream, creating a mixed stream that moves at an intermediate speed. In other words, a gas ejector uses high-pressure gas to compress and discharge low-pressure gas without the use of moving parts. As used herein, a gas ejector may also be referred to as an aspirator, venturi nozzle, venturi pump, venturi nozzle ejector, jet pump, jet mixer, nozzle ejector, air ejector, and ejector.

[0099] One or more gas ejectors of the present disclosure may be a venturi pump that utilizes the "venturi effect" to efficiently exhaust gas from the roughing pump and reduce the pressure at the outlet of the roughing pump. The "venturi effect" is the reduction in fluid pressure caused when a fluid flows through a constricted portion of a channel. According to some embodiments, Figure 6 FIG6 is a schematic cross-sectional view of an exemplary Venturi pump 600, illustrating the pressure gradient across the entire length of the Venturi pump 600. Injection gas is introduced as a motive flow at high velocity and high inlet pressure. The main body of the Venturi pump 600 comprises a converging power section 610, a diverging discharge section 620, and a Venturi gap 630 between the converging power section 610 and the diverging discharge section 620. The converging power section 610 increases the fluid velocity of the high-pressure gas flow. This increase in fluid velocity creates a low-pressure zone, which provides suction to draw in the low-pressure gas flow. The low-pressure zone can be provided in the suction port 640 of the Venturi pump 600, wherein the suction port 640 is in fluid communication with the converging power section 610. The suction port 640 can be connected to a device requiring vacuum or reduced pressure. The low-pressure gas flow mixes with the high-pressure gas flow in the converging power section 610. The mixed gas flow is conveyed through a venturi gap 630 located downstream of the converging power section 610. The venturi gap 630 is a constricted portion of the body of the venturi pump 600 where the mixed gas flow is maintained at a low pressure and high fluid velocity. The mixed gas flow then flows through a diverging discharge section 620, which in turn reduces the fluid velocity and increases the pressure, thereby compressing the mixed gas flow. This enables the venturi pump 600 to discharge the mixed gas flow at a pressure greater than that at the suction port 640.

[0100] Gas ejectors or Venturi pumps are commonly used in many large-scale industrial applications. In one example, Venturi pumps are used to transport and move powders, granules, and bulk solids in the food industry. In another example, Venturi pumps can create a vacuum for pick-and-place operations. In yet another example, Venturi pumps are used to exhaust steam in the power plant industry. In yet another example, Venturi pumps are used to determine fuel or combustion pressure in jet or rocket engines.

[0101] However, one or more venturi pumps of the present invention are used with a vacuum pump system of a semiconductor processing apparatus to reduce the pressure at the discharge of a roughing pump and to limit deposits in the roughing pump. The one or more venturi pumps are connected in series with the roughing pump or primary pump of the vacuum pump system. An example of a vacuum pump system including one or more venturi pumps is shown in FIG. Figure 7 、 8A , 8B, and 8C. Semiconductor processing equipment may include processing chambers to perform deposition and etching operations.

[0102] In an alternative embodiment, multiple venturi pumps are used as primary pumps or pre-pumps for a vacuum pumping system. Multiple venturi pumps can be connected in series and / or in parallel to provide multi-stage venturi pre-pumps. Multiple venturi pumps can be connected to the exhaust of a processing chamber, wherein the processing chamber is configured to perform deposition and etching operations. Multiple venturi pumps can be used to exhaust deposition precursors and etching gases from the processing chamber. In some embodiments, multiple venturi pumps can be configured to achieve a "partial" vacuum or a "rough" vacuum in the processing chamber, wherein the processing chamber can be brought to a pressure between about 1 Torr and atmospheric pressure. Instead of using a roughing pump, multiple venturi pumps can perform the same or similar function as a roughing pump, but the multiple venturi pumps do not have any moving parts. In some embodiments, the number of multiple venturi pumps can be between about 2 and about 6. Using multiple venturi pumps as primary pumps in a vacuum pumping system can avoid the formation of unwanted byproducts between deposition precursors and etching gases. An example of a vacuum pumping system using multiple venturi pumps as pre-pumps or primary pumps for a processing chamber is shown in Figure 9 middle.

[0103] In some embodiments, the venturi pump may be equipped with a connector or component to be mounted on a pumping device of a semiconductor processing device. In some embodiments, the venturi pump may be located between the abatement assembly / system and the roughing pump, wherein the venturi pump is located downstream of the roughing pump and upstream of the abatement assembly / system. According to some embodiments, Figure 7 An exemplary venturi pump 700 is shown having components configured to connect to a vacuum pump system. Figure 7In the figure, a first connector 710 is used to connect the venturi pump 700 to the outlet of a roughing pump (not shown). The first connector 710 receives exhaust gas from the roughing pump, which may include deposition precursors and etching gases exhausted from processing equipment. The second connector 720 is used to receive injection gas at a high inlet pressure as a motive flow. The injection gas is provided through the main body of the venturi pump 700. The injection gas mixes with the exhaust gas from the roughing pump received from the first connector 710. In some embodiments, the injection gas includes an inert gas such as helium (He), N2, or clean dry air. The third connector 730 provides a connection to an abatement assembly to process the gas exhausted from the venturi pump 700. Such gases may include, for example, injection gas (e.g., N2), deposition precursors (e.g., aminosilane), etching gases (e.g., HBr), purge gases, and reactive gases (e.g., CH2F2, CF4, Cl2, SiCl4, NF3, O2, O3, etc.), which may be used during wafer processing and / or cleaning operations. Therefore, the venturi pump 700 may be provided with one or more connectors for connecting to a roughing pump of a semiconductor processing tool (ALD processing tool) and for connecting to a facility abatement component / system. The venturi pump 700 receives exhaust gas from the roughing pump at a reduced pressure and discharges it from the venturi pump 700 at an increased pressure. The venturi pump 700 is used to efficiently discharge gas from the moving parts of the roughing pump and to prevent deposits in the roughing pump.

[0104] Figure 8A According to some embodiments, a schematic diagram of an exemplary vacuum pump system 800a is shown, including a roughing pump 810, wherein the roughing pump 810 is modified to be connected in series with a gas ejector. In some embodiments, the gas ejector includes one or more venturi pumps 820. The vacuum pump system 800a includes a roughing pump 810. In some embodiments, the roughing pump 810 can be used in combination with an optional booster pump 840, or can optionally include a booster pump 840. Deposition precursors and etching gases can be exhausted from the processing chamber via the roughing pump 810. The roughing pump 810 can include one or more moving parts, wherein the one or more moving parts can include a rotor assembly. In some embodiments, a purge gas 830 (e.g., N2) can be provided to flow through the roughing pump 810 and cause the roughing pump 810 to exhaust the deposition precursors and etching gases. The exhausted deposition precursors and etching gases can exit the roughing pump 810 at an outlet 812 of the roughing pump 810. The outlet 812 of the roughing pump 810 may be a discharge port.

[0105] One or more venturi pumps 820 can be connected to the outlet 812 or exhaust port of the roughing pump 810. In some embodiments, an air intake 822 leading to a low pressure zone of the one or more venturi pumps 820 can be connected to the outlet 812 of the roughing pump 810. The one or more venturi pumps 820 are connected in series with the roughing pump 810 and are located downstream of the roughing pump 810. The one or more venturi pumps 820 are configured to reduce the pressure at the outlet 812 of the roughing pump 810. Typically, the deposition precursors and etching gases are discharged from the roughing pump 810 at a certain exhaust pressure, which is about atmospheric pressure or near atmospheric pressure. The exhaust pressure at the outlet 812 of the roughing pump 810 is reduced to significantly less than atmospheric pressure by the one or more venturi pumps 820. For example, the discharge pressure at the outlet 812 of the roughing pump 810 is equal to or less than about 380 Torr, equal to or less than about 250 Torr, or equal to or less than about 200 Torr. The reduced discharge pressure can prevent or limit the formation of deposited byproducts at the outlet 812 of the roughing pump 810. In some embodiments, one or more venturi pumps 820 reduce the overall pressure of various stages of the roughing pump 810 itself.

[0106] The above aspects of the Venturi pump can be applied to Figure 8A The Venturi pump 820 in the Figure 5 The vacuum pump system in the Figure 7 One or more connectors for the venturi pump in the Figure 8A The modified vacuum pump system 800a in FIG. Figure 8AOne or more venturi pumps 820 in the venturi pump 820 provide a high-pressure gas flow that creates a low-pressure zone in the suction port 822, thereby causing an intake flow that draws in the discharged deposition precursor and etching gas. Specifically, an injection gas is flowed into the body of each of the venturi pumps 820. In some embodiments, the injection gas comprises an inert gas (e.g., helium (He)), clean dry air, or N2. In some embodiments, the injection gas is flowed at a pressure between about 40 psig and about 80 psig. In some embodiments, the injection gas is flowed at room temperature or at an elevated temperature. For example, the injection gas is flowed at a temperature between about 20°C and about 100°C. The injection gas can entrain and mix with the discharged deposition precursor and etching gas. The mixed gas is then effectively discharged from the one or more venturi pumps 820 to an abatement assembly 814, which is configured to be connected to an outlet 824 of the one or more venturi pumps 820. The abatement assembly 814 is configured to process the mixed gas (including the exhausted deposition precursor and etching gas). Taking advantage of the Venturi effect described above, the exhaust pressure at the outlet 824 of the one or more Venturi pumps 820 can be greater than the exhaust pressure at the outlet 812 of the roughing pump 810, wherein the exhaust pressure at the outlet 824 of the Venturi pump 820 can be at atmospheric pressure or near atmospheric pressure. For example, the exhaust pressure at the outlet 824 of the one or more Venturi pumps 820 is equal to or greater than approximately 525 Torr, equal to or greater than approximately 600 Torr, equal to or greater than approximately 700 Torr, or equal to or greater than approximately 760 Torr.

[0107] Other designs or embodiments of the vacuum pump system may incorporate a gas ejector (e.g., a venturi pump) into the vacuum pump system. Figure 8B A schematic diagram of an exemplary vacuum pump system 800b is shown, comprising a roughing pump 810 connected in series with a gas ejector. The gas ejector may be a venturi pump 850. The vacuum pump system 800b comprises the roughing pump 810 and, optionally, a booster pump 840 as described above. Figure 8BIn the embodiment, the venturi pump 850 includes a body, wherein the body includes a converging power section, a diverging discharge section, and a venturi gap between the converging power section and the diverging discharge section. Deposition precursors and etching gases are discharged to the outlet 812 of the roughing pump 810, which is connected to the suction port 822 of the venturi pump 850. The discharged deposition precursors and etching gases are then drawn into the converging power section of the venturi pump 850 from the suction port 822. The high-pressure gas flow is introduced by injecting an injection fluid into the converging power section. The injection fluid mixes with the discharged deposition precursors and etching gases in the converging power section, and the mixed gas flows through the venturi gap and is discharged in the diverging discharge section. In some embodiments, the venturi pump 850 includes a corrosion-resistant material or is coated with a corrosion-resistant material. In this way, the venturi pump 850 is protected from the caustic chemical effects involved in the plasma etching process.

[0108] Figure 8C According to some embodiments, a schematic diagram of an exemplary vacuum pump system 800c including a roughing pump 810 is shown, wherein the roughing pump 810 is connected in series with a plurality of gas injectors 860a, 860b. A plurality of gas injectors 860a, 860b can provide gas injectors in multiple stages, which can be connected in series or in parallel with each other. A plurality of gas injectors 860a, 860b can be used to further reduce the exhaust pressure at the outlet 812 of the roughing pump 810. In addition, a plurality of gas injectors 860a, 860b can be used to increase the suction flow at the outlet 812 of the roughing pump 810, thereby effectively discharging the deposition precursor and etching gas from the roughing pump 810.

[0109] Incorporating one or more gas ejectors or venturi pumps into the pre-pump can prevent accumulation of deposition byproducts in the vacuum pump system. Embodiments using such gas ejectors can be combined with one or more of the aforementioned embodiments for preventing accumulation of deposition byproducts, including embodiments involving separate pumps, separate inlets, surface coatings, pump heating, longer and more accurately measured purge times, and cleaning chemicals. In one example, during a cleaning operation, a reactive gas (e.g., plasma-activated species of fluorine, chlorine, oxygen, ozone, or a combination thereof) can be flowed through the roughing pump, where the reactive gas, along with the remaining deposition precursor and etching gas, is exhausted at the outlet of a primary pump connected to one or more venturi pumps. In another example, the surfaces of the pump components can be heated to an elevated temperature while the pump components exhaust the deposition precursor and etching gas at the outlet of the primary pump connected to one or more venturi pumps.

[0110] Figure 9A schematic diagram of an exemplary vacuum pump system 900 is shown, according to some embodiments, including multiple Venturi pumps 920a, 920b, and 920c, wherein the multiple Venturi pumps 920a, 920b, and 920c serve as a multi-stage Venturi pre-pump 910 of the vacuum pump system 900. The vacuum pump system 900 includes the multi-stage Venturi pre-pump 910, which replaces a roughing pump. The multi-stage Venturi pre-pump 910 includes the multiple Venturi pumps 920a, 920b, and 920c connected in series. The multi-stage Venturi pre-pump 910 functions as an effective roughing pump and is fluidically coupled to a turbomolecular pump 930. in conclusion

[0111] In the above 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 of these specific details. In other instances, routine process operations are not described in detail in order not to obscure the disclosed embodiments. Although the disclosed embodiments are described in conjunction with specific embodiments, it should be understood that this is not intended to limit the disclosed embodiments.

[0112] The above embodiments have been described in detail for purposes of clarity of understanding, but it will be appreciated that certain changes and modifications may be made within the scope of the appended claims. It should be noted that there are many alternative ways of implementing the processes, systems, and apparatus of the embodiments herein. Accordingly, the embodiments herein are to be considered in all respects illustrative and not restrictive, and the embodiments are not to be limited to the details provided herein.

Claims

1. A vacuum pump system for exhausting one or more etching gases and one or more deposition gases from a processing chamber, the vacuum pump system comprising: a roughing pump through which deposition precursors and etching gases are exhausted from the processing chamber, wherein the roughing pump includes one or more shafts supporting one or more rotor assemblies, each shaft having a passage for receiving a heat source, wherein the heat source includes electrical wires, a heat lamp, or a heated fluid; and A system controller configured with instructions for: exhausting the deposition precursor or the etching gas from the process chamber; and The heat source is used to heat the inner surfaces of the one or more shafts and the one or more rotor components to an elevated temperature while exhausting the deposition precursor or the etching gas.

2. The vacuum pump system according to claim 1, wherein: The elevated temperature is equal to or greater than 160°C.

3. The vacuum pump system according to claim 1, wherein: The elevated temperature is sufficient to prevent accumulation of deposition byproducts due to reactions between the etching gas and the deposition gas.

4. The vacuum pump system according to claim 1, wherein: A system controller configured with instructions to heat the inner surface is configured with instructions to absorb thermal energy from a reservoir external to the vacuum pump system and transfer the thermal energy to the inner surface via radiation and / or conduction.

5. The vacuum pump system according to claim 1, wherein: The etching gas includes hydrogen bromide, and the deposition precursor includes an aminosilane precursor.

6. The vacuum pump system according to claim 1, wherein: Roughing pumps also include: A stator assembly surrounds the one or more rotor assemblies of the roughing pump, wherein the deposition precursor and the etching gas pass through channels in the stator assembly.

7. The vacuum pump system according to claim 1, wherein: Each of the one or more shafts includes an inner conductive material and an outer insulating material.

8. A vacuum pump system for exhausting one or more etching gases and one or more deposition gases from a processing chamber, the vacuum pump system comprising: a roughing pump through which deposition precursors and etching gases are exhausted from the processing chamber, wherein the roughing pump includes one or more shafts supporting one or more rotor assemblies; A system controller configured with instructions to: exhausting the deposition precursor or the etching gas from the process chamber; and The surfaces of the one or more shafts and the one or more rotor assemblies are heated to an elevated temperature by flowing a heated purge gas over the surfaces of the one or more shafts and the one or more rotor assemblies.

9. The vacuum pump system according to claim 8, wherein: The elevated temperature is equal to or greater than 160°C.

10. The vacuum pump system according to claim 8, wherein: A system controller configured with instructions to heat the surface is configured with instructions to flow a heated sweep gas while exhausting the deposition precursor or etching gas.

11. The vacuum pump system according to claim 8, wherein: The system controller is configured with instructions to: exhausting the deposition precursor from the process chamber through a passage in the roughing pump; as well as The etching gas is exhausted from the processing chamber through a passage in the roughing pump, wherein the flow of the heated sweep gas occurs between exhausting the deposition precursor and exhausting the etching gas.

12. A vacuum pump system for exhausting one or more etching gases and one or more deposition gases from the processing chamber, the vacuum pump system comprising: a roughing pump, through which the deposition precursor and the etching gas are exhausted from the processing chamber, wherein the roughing pump comprises: one or more rotor assemblies; one or more shafts for supporting the one or more rotor assemblies; and A stator assembly is provided for surrounding the one or more rotor assemblies, wherein the one or more rotor assemblies, the one or more shafts, and the stator assembly are all made of a metallic material coated with a corrosion-resistant surface coating.

13. The vacuum pump system according to claim 12, wherein: The roughing pump further comprises: One or more inlets are connected to the passageway leading to the one or more rotor assemblies, wherein the one or more inlets are coated with a corrosion resistant coating.

14. The vacuum pump system according to claim 12, wherein: The corrosion resistant surface coatings include plated nickel, plated cobalt, titanium nitride (TiN), Inconel, Hastelloy, ceramic materials, fluoropolymers, and combinations thereof.

15. The vacuum pump system according to claim 12, wherein: The corrosion-resistant surface coating may prevent accumulation of deposition byproducts due to reactions between the etching gas and the deposition gas.

16. The vacuum pump system according to claim 12, wherein: The etching gas includes hydrogen bromide, and the deposition precursor includes an aminosilane precursor.

17. The vacuum pump system according to claim 12, wherein: Each shaft has a channel for receiving a heat source, including electrical wires, heat lamps, or heated fluid.

18. The vacuum pump system according to claim 17, wherein: The heat source is configured to heat the inner surfaces of the one or more shafts and the one or more rotor assemblies to a temperature equal to or greater than 160°C.

19. A method for cleaning a pump, the method comprising: performing an etching operation on the wafer in a processing chamber, wherein one or more etching gases are exhausted by a pump in fluid communication with the processing chamber; purging the one or more etching gases from the pump according to a first predetermined duration; performing a deposition operation on the wafer in the process chamber, wherein one or more deposition precursors are discharged by the pump; as well as The one or more deposition precursors are purged from the pump according to a second predetermined duration.

20. The method according to claim 19, wherein The first predetermined duration and the second predetermined duration are both determined by residual gas analysis.

21. The method according to claim 19, wherein The first predetermined duration and the second predetermined duration are both determined by Fourier transform infrared gas analysis.

22. The method of claim 19, further comprising: measuring a first purge time for purging the one or more etching gases from the pump to determine the first predetermined duration; as well as A second purge time for purging the one or more deposition gases from the pump is measured to determine the second predetermined duration.

23. A method of cleaning a vacuum pump system, the method comprising: performing one or more deposition operations on the wafer in the processing chamber; performing one or more etching operations on the wafer in a processing chamber; as well as A cleaning operation is performed using a reactive gas flowing through the vacuum pump system, the cleaning operation being performed before or after the one or more etching operations, wherein the vacuum pump system is in fluid communication with the processing chamber.

24. The method according to claim 23, wherein The cleaning operation is performed between the deposition operation and the etching operation.

25. The method according to claim 23, wherein The wafer is positioned within the processing chamber while the one or more deposition operations, the one or more etching operations, and the cleaning operation are performed.

26. The method according to claim 23, wherein When the cleaning operation is performed, no wafer is present in the processing chamber.

27. The method of claim 23, wherein the reactive gas comprises nitrogen trifluoride, sulfur hexafluoride, carbon tetrafluoride, chlorine trifluoride, chlorine, oxygen, ozone, or a combination thereof.

28. The method of claim 27, wherein the reactive gas comprises ozone.

29. The method of claim 23, wherein the reactive gas comprises radicals and / or ions of fluorine, chlorine, oxygen, or a combination thereof.

30. The method of claim 23, further comprising: The reactive gas is generated in situ within the processing chamber by a plasma reaction.

31. The method of claim 23, further comprising: The reactive gas is generated by a plasma source located in a foreline, wherein the foreline provides an interconnection between the vacuum pump system and the processing chamber.

32. The method of claim 23, further comprising: The reactive gas is generated by a remote plasma source located external to the foreline, wherein the foreline provides an interconnection between the vacuum pump system and the processing chamber.

33. A vacuum pump system for exhausting one or more etching gases and one or more deposition gases from a processing chamber, the vacuum pump system comprising: a roughing pump through which deposition precursors and etching gases are exhausted from the processing chamber; as well as A gas ejector is connected in series with the roughing pump and located downstream of the roughing pump, wherein the gas ejector is configured to reduce the pressure at an outlet of the roughing pump.

34. The vacuum pump system of claim 33, wherein: The gas injector is a venturi pump connected to an outlet of the roughing pump, wherein the venturi pump is configured to allow injection gas to flow through a body of the venturi pump and mix with the discharged deposition precursor and etching gas within the body of the venturi pump.

35. The vacuum pump system of claim 34, wherein: The injection gas includes inert gas, clean dry air or nitrogen.

36. The vacuum pump system of claim 34, wherein: The injection gas flows at a pressure between 40 psig and 80 psig, and the injection gas flows at a temperature between 20°C and 100°C.

37. The vacuum pump system of claim 33, further comprising: An abatement assembly is provided for processing the deposition precursors and the exhausted gases, wherein the gas injector is positioned between the abatement assembly and the roughing pump.

38. The vacuum pump system of claim 33, further comprising: One or more additional gas injectors connected in series with the gas injector, wherein the one or more additional gas injectors are configured to further reduce the pressure at the outlet of the roughing pump.

39. An apparatus comprising: processing room; an etching gas delivery system configured to introduce one or more etching gases into the processing chamber; as well as a deposition precursor delivery system configured to introduce one or more deposition precursors into the processing chamber; as well as a vacuum pump system in fluid communication with the process chamber, wherein the vacuum pump system includes a roughing pump, wherein the roughing pump includes: a first exhaust port in fluid communication with the process chamber for receiving the one or more etching gases and the one or more deposition precursors when the roughing pump operates in a low pressure range, wherein the low pressure range is between 0.1 Torr and 1 Torr; and A second exhaust port is in fluid communication with the process chamber for receiving one or more etching gases and one or more deposition precursors when the roughing pump operates in a high pressure range, wherein the high pressure range is between 1 Torr and 10 Torr.

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