Preventing contamination of substrates during pressure changes in a processing system

Abstract

An implementation is disclosed for minimizing contamination of a substrate during pressure changes in a substrate processing system. Over the duration of a pressure change (increase or decrease) in a chamber of the substrate processing system, the flow rate is adjusted multiple times to reduce the generation of contaminating particles in the environment of the chamber. In some examples, the flow rate is continuously changed using at least one dynamic valve that allows continuous control over the pressure dynamics of the chamber.

Description

[Technical Field]

[0001] TECHNICAL FIELD This present specification relates generally to improving the quality of substrates (e.g., wafers) in electronic device manufacturing systems, and more particularly to methods for minimizing the presence of contaminants in the environment of substrate processing equipment. [Background technology]

[0002] Modern materials manufacturing often involves a variety of etching and deposition techniques, including plasma etching, chemical vapor deposition, and physical vapor deposition (PVD), in which one or more selected types of atoms are deposited onto specially prepared substrates held in a low- or high-vacuum environment provided by a vacuum deposition chamber. Materials produced using this technique include single crystals, semiconductor films, fine coatings, and numerous other substances used in practical applications such as electronic device manufacturing. Many of these applications require certain standards for the purity of the material grown within the deposition chamber. The need to maintain environmental separation between chambers and minimize their exposure to the ambient atmosphere and the contaminants therein has led to various robotic techniques for substrate manipulation and chamber control. Automated manipulation often involves robots moving substrates between chambers with vastly different environments.

[0003] Aspects and embodiments of the present disclosure will be more fully understood from the detailed description provided below and the accompanying drawings, which should not be construed as limiting the disclosure to the particular aspects or embodiments, but which are for purposes of illustration and understanding only. The drawings are set forth below for illustrative purposes and are not necessarily drawn to scale. [Brief explanation of the drawings]

[0004] [Figure 1] 1 is a schematic diagram of a processing system (eg, a substrate processing system) according to some embodiments of the present disclosure. [Figure 2]1 is a schematic diagram of a substrate processing system that enables effective prevention of substrate contamination during pressure changes, according to some embodiments of the present disclosure. [Figure 3] 10A-10C are schematic diagrams of types of variations in pressure to a load lock chamber (top graph) and flow rate of gas into the load lock chamber (bottom graph) determined to minimize contamination of substrates during the pump-up phase of substrate manufacturing, according to some embodiments of the present disclosure. [Figure 4] FIG. 10 is a schematic diagram of an example algorithm used to determine a target pressure and a target flow rate for a pump-up process that reduces the presence of contaminants in a substrate processing system, according to some embodiments of the present disclosure. [Figure 5] 10A-10C are schematic diagrams illustrating types of changes in load lock chamber pressure (top graph) and flow rate of gas flowing out of the load lock chamber (bottom graph) determined to minimize liquid condensation during a pump-down phase of a substrate processing system, according to some embodiments of the present disclosure. [Figure 6] FIG. 10 is a schematic diagram of an example algorithm used to determine a target pressure and a target flow rate during a pump-down process to reduce liquid condensation in a substrate processing system, according to some embodiments of the present disclosure. [Figure 7A] FIG. 1 illustrates an example valve control system that may be used to prevent product contamination in a substrate processing system during pressure changes, according to some embodiments of the present disclosure. [Figure 7B] FIG. 1 illustrates another example valve control system for preventing product contamination in a substrate processing system during pressure changes, according to some embodiments of the present disclosure. [Figure 8] FIG. 1 is a flow diagram of a method for defining pressure changes that minimize contaminant generation in a substrate processing system according to some embodiments of the present disclosure. [Figure 9] 1 is a flow diagram of a method for moving a substrate from a first compartment of a substrate processing system to a second compartment of the substrate processing system while minimizing exposure of the material to contaminants according to some embodiments of the present disclosure. [Figure 10] FIG. 1 is a flow diagram of a method for modeling types of pressure and flow rate changes to minimize contaminant generation in a substrate processing system, according to some embodiments of the present disclosure. [Figure 11] FIG. 1 is a block diagram of an example processing device operation in accordance with one or more aspects of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0005] In a substrate processing system, a substrate (e.g., a silicon wafer) can undergo several processing stages. For example, an unprocessed substrate can be delivered to the processing system in a substrate carrier, such as a front-opening unified pod (FOUP). The FOUP can be docked to a factory interface (front-end module). A robot arm of a factory interface robot can remove the substrate from the FOUP and deliver it to a load lock (degassing chamber). Another robot arm can then extend from the transfer chamber, remove the substrate from the load lock chamber, and deliver it to one or more processing chambers accessible from the transfer chamber for processing. Multiple processing chambers can be provided. The substrate can be moved (e.g., by a transfer chamber robot) between various processing chambers where various stages of processing can be performed, such as mask deposition, etching, mask removal, substrate deposition, etc. After processing, the substrate can be returned to the FOUP (same or different) through, for example, a transfer chamber, a load lock chamber, a factory interface, etc. Each chamber can have a unique environment, such as, for example, temperature, pressure, gas type, etc. For example, the transfer chamber (and processing chamber) may be operated at a pressure P T The factory interface (and FOUP) can have a low or high vacuum environment with a pressure P close to atmospheric pressure. IThus, the load lock chamber (degas chamber, or any other chamber) can function as an air lock between the factory interface and the transfer chamber. Specifically, when a substrate is to be moved from the factory interface to the load lock chamber (and then to the transfer chamber), the pressure in the load lock chamber can be adjusted to P I The pressure in the transfer chamber P T The pump-down process can be gradually reduced to P. Such a pump-down process, if performed rapidly, can reduce the temperature within the load lock chamber and result in condensation of various vapors (e.g., water vapor) on the substrate. Condensation subsequently carried by the substrate into the transfer chamber and processing chambers can adversely affect the manufacturing process and the quality of the final product (e.g., by preventing deposited materials from properly adhering to the substrate). On the other hand, if performed slowly, the pump-down process reduces the manufacturing output (throughput) of the system. Similarly, as substrates are moved from the transfer chamber to the load lock chamber (and then to the factory interface), the pressure within the load lock chamber can drop to P T to the pressure P in the factory interface IThe pump-up process, if performed too quickly, can release various particles remaining (adsorbed) on the walls of the load-lock chamber into the load-chamber environment. These particles can then land on the substrate and become contaminants. Slowing down the pump-up process, as in the case of the pump-down process, reduces the number of particles that are detached (resuspended), but also reduces manufacturing throughput. Existing techniques involve dividing the pump-down process into two phases: a slow first phase and a fast second phase. The first phase is characterized by a first (low) flow rate (vent rate) and a corresponding slow increase in pressure inside the load-lock chamber. The second phase begins by switching the flow rate to a second (increased) flow rate value. The pressure then increases even more rapidly. Such two-stage flow control reduces the number of particles that can detach by limiting the rate at which pressure increases during the first (and more sensitive) phase of the pump-up process. Although they do reduce the number of contaminants released into the load lock chamber environment to some extent, existing two-stage techniques have limited flexibility and adjustability because the first vent rate value and the second vent rate value are set empirically.

[0006] Aspects and embodiments of the present disclosure address these and other shortcomings of existing pump-down and pump-up techniques used in substrate manufacturing. Described herein, among other things, are implementations that enable the determination of optimal types of changes in the pressure P(t) within a load-lock chamber during both the pump-down and pump-up processes to minimize the release of contaminants into the load-lock chamber environment. In some embodiments, contaminant minimization is based on simulations that consider actual physical processes that determine particle resuspension in the environment during the pump-up phase and vapor condensation during the pump-down phase. Additionally, dynamic valve control settings are described that enable the setting and control of the flow rates F(t) of gas streams flowing into or out of the load-lock chamber at multiple points (time points) in the respective processes. In some embodiments, each of the pump-up and pump-down phases may involve setting three, four, or more different flow rates calculated to minimize the generation of contaminants within the load-lock chamber. In some embodiments, each of the pump-up and pump-down stages may involve setting the flow rate F(t) in a continuous or quasi-continuous manner, which may involve setting (or adjusting) the flow rate F(t) at a large number N (e.g., N=10, 20, 50, etc.) of times over the duration of the respective stage.

[0007] FIG. 1 illustrates a schematic diagram of a processing system 100 (e.g., a substrate processing system) according to some embodiments of the present disclosure. The processing system 100 includes a factory interface (FI) 101 and load ports 128 (e.g., load ports 128A-D). In some embodiments, the load ports 128A-D are directly mounted to (e.g., sealed relative to) the FI 101. An enclosure system 130 (e.g., a cassette, FOUP, process kit enclosure system, etc.) is configured to removably couple to (e.g., dock with) the load ports 128A-D. Referring to FIG. 1 , enclosure system 130A is coupled to load port 128A, enclosure system 130B is coupled to load port 128B, enclosure system 130C is coupled to load port 128C, and enclosure system 130D is coupled to load port 128D. In some embodiments, one or more enclosure systems 130 are coupled to the load ports 128 for moving substrates and / or other products into and out of the processing system 100. Each of the enclosure systems 130 may seal to its respective load port 128. In some embodiments, a first enclosure system 130A is docked to the load port 128A. Once such operations and operations are performed, the first enclosure system 130A is decoupled from the load port 128A, and then a second enclosure system 130B (e.g., a FOUP containing a substrate) is docked to the same load port 128A. In some embodiments, the enclosure system 130 (e.g., enclosure system 130A) is a system for performing calibration and diagnostic operations. In some embodiments, the enclosure system 130 (e.g., enclosure system 130B) is a process kit enclosure system for moving contents 110, such as process kit rings, into and out of the processing system 100.

[0008] In some embodiments, the load port 128 includes a front interface that forms an opening. The load port 128 additionally includes a horizontal surface that supports the enclosure systems 130. Each enclosure system 130 has a front interface that forms a vertical opening. The front interface of the enclosure system 130 is sized to interface with the front interface of the load port 128 (e.g., the vertical opening of the enclosure system 130 is approximately the same size as the vertical opening of the load port 128). The enclosure system 130 is positioned on the horizontal surface of the load port 128, and the vertical opening of the enclosure system 130 aligns with the vertical opening of the load port 128. The front interface of the enclosure system 130 interconnects (e.g., is clamped, fastened, or sealed) with the front interface of the load port 128. The bottom plate (e.g., base plate) of the enclosure system 130 has features that engage with the horizontal surfaces of the load port 128 (load features such as recesses or receptacles that engage with the load port's kinematic pin features, load port features for pin clearance and / or enclosure system docking tray latch clamp features). The same load port 128 can be used for different types of enclosure systems 130.

[0009] In some embodiments, the enclosure system 130B (e.g., a process kit enclosure system) contains one or more contents 110 (e.g., one or more of a process kit ring, an empty process kit ring carrier, a process kit ring positioned on a process kit ring carrier, a placement verification wafer, etc.). In some examples, the enclosure system 130B is coupled to the FI 101 (e.g., via a load port 128) to enable automated movement of a process kit ring on a process kit ring carrier into the processing system 100 for replacement of a used process kit ring.

[0010] In some embodiments, the processing system 100 also includes first vacuum ports 103a, 103b coupling the FI 101 to the respective load lock chambers 104a, 104b. Second vacuum ports 105a, 105b are coupled to the respective load lock chambers 104a, 104b and are disposed between the load lock chambers 104a, 104b and the transfer chamber 106 to facilitate movement of substrates and other contents 110 (e.g., process kit rings) to the transfer chamber 106. In some embodiments, the processing system 100 includes and / or uses one or more load lock chambers 104 and a corresponding number of vacuum ports 103, 105 (e.g., the processing system 100 includes a single load lock chamber 104, a single first vacuum port 103, and a single second vacuum port 105). The transfer chamber 106 includes multiple processing chambers 107 (e.g., four processing chambers 107, six processing chambers 107, etc.) disposed around and coupled thereto. The processing chambers 107 are coupled to the transfer chamber 106 through respective ports 108, such as slit valves. In some embodiments, the FI 101 is at a higher pressure (e.g., atmospheric pressure) and the transfer chamber 106 is at a lower pressure (e.g., vacuum). Each load lock chamber 104 (e.g., a degassing chamber) has a first door (e.g., first vacuum port 103) to seal the load lock chamber 104 from the FI 101 and a second door (e.g., second vacuum port 105) to seal the load lock chamber 104 from the transfer chamber 106. To move contents from the FI 101 into the load lock chamber 104 while the first door is open and the second door is closed, the first door is closed, the pressure in the load lock chamber 104 is reduced to match the pressure in the transfer chamber 106, the second door is opened, and the contents are moved out of the load lock chamber 104. A local center finding (LCF) device should be used to align the contents with the transfer chamber 106 (eg, before entering the processing chamber 107, after exiting the processing chamber 107).

[0011] In some embodiments, the processing chamber 107 includes one or more of an etch chamber, a deposition chamber (including atomic layer deposition, chemical vapor deposition, physical vapor deposition or plasma-enhanced versions thereof), an anneal chamber, or the like.

[0012] The factory interface 101 includes a factory interface robot 111. The factory interface robot 111 includes a robot arm, such as a Selective Compliance Assembly Robot Arm (SCARA) robot. Examples of SCARA robots include a two-link SCARA robot, a three-link SCARA robot, a four-link SCARA robot, etc. The factory interface robot 111 includes an end effector at one end of the robot arm. The end effector is configured to lift and handle specific objects, such as wafers. Alternatively, or additionally, the end effector is configured to handle objects, such as calibration substrates and process kit rings (edge ​​rings). The robot arm has one or more linkages or members (e.g., wrist members, upper arm members, forearm members) configured to move the end effector to different orientations and locations.

[0013] The factory interface robot 111 is configured to move objects between the enclosure system 130 (e.g., cassettes, FOUPs) and the load lock chambers 104a, 104b (or load ports). The factory interface robot 111 is taught a fixed position relative to the load port 128 using the enclosure system 130 in an embodiment. The fixed position in one embodiment corresponds to a center position of the enclosure system 130A located on the particular load port 128, which in an embodiment also corresponds to a center position of the enclosure system 130B located on the particular load port 128. Alternatively, the fixed position may correspond to another fixed position within the enclosure system 130, such as the front or rear of the enclosure system 130. The factory interface robot 111 is calibrated using the enclosure system 130 in some embodiments. The factory interface robot 111 is diagnosed using the enclosure system 130 in some embodiments.

[0014] The transfer chamber 106 includes a transfer chamber robot 112. The transfer chamber robot 112 includes a robot arm with an end effector at one end of the robot arm. The end effector is configured to handle a particular object, such as a wafer. In some embodiments, the transfer chamber robot 112 is a SCARA robot, although in some embodiments, the transfer chamber robot 112 may have fewer linkages and / or fewer degrees of freedom than the factory interface robot 111.

[0015] Controller 109 controls various aspects of processing system 100. Controller 109 is or includes a computing device such as a personal computer, a server computer, a programmable logic controller (PLC), a microcontroller, etc. Controller 109 includes one or more processing devices, which in some embodiments are general-purpose processing devices such as a microprocessor, a central processing unit, etc. More specifically, in some implementations, the processing device is a complex instruction set computing (CISC) microprocessor, a reduced instruction set computing (RISC) microprocessor, a very long instruction word (VLIW) microprocessor, or a processor implementing other instruction sets or combinations of instruction sets. In some embodiments, the processing device is one or more special-purpose processing devices such as an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a digital signal processor (DSP), a network processor, etc. In some embodiments, controller 109 includes a data storage device (e.g., one or more disk drives and / or solid-state drives), main memory, static memory, a network interface, and / or other components. In some embodiments, the controller 109 executes the instructions to perform one or more of the methods or processes described herein. The instructions are stored in a computer-readable storage medium, which (during execution of the instructions) includes a main memory, static memory, secondary storage, and / or processing device. The controller 109, in some embodiments, receives signals from and sends control to the factory interface robot 111 and the wafer transfer chamber robot 112.

[0016] According to one embodiment of the disclosure, to move contents 110 (e.g., substrates or process kit rings) into processing chambers 107, the contents 110 are removed from process kit enclosure system 130B via factory interface robot 111 located within FI 101. Factory interface robot 111 moves contents 110 through one of first vacuum ports 103a, 103b and into respective load lock chambers 104a, 104b. Transfer chamber robot 112 located within transfer chamber 106 removes contents 110 from one of load lock chambers 104a, 104b through second vacuum port 105a or 105b. Transfer chamber robot 112 moves contents 110 into transfer chamber 106, where they are transferred to processing chambers 107 through respective ports 108. After processing, the processed contents 110 (eg, used process kit rings) are removed from the processing system 100 in the reverse manner described herein.

[0017] The processing system 100 includes a chamber, such as FI101 (e.g., an equipment front-end module, EFEM), and adjacent chambers adjacent to FI101 (e.g., a load port 128, an enclosure system 130, an SSP, a load lock chamber 104 such as a degassing chamber, etc.). Some or all of the chambers can be sealed. In some embodiments, an inert gas (e.g., one or more of nitrogen, argon, neon, helium, krypton, or xenon) is provided to one or more of the chambers (e.g., FI101 and / or an adjacent chamber) to achieve one or more inert environments. In some examples, FI101 is an inert EFEM that maintains an inert environment (e.g., an inert EFEM mini-environment) within FI101, thereby eliminating the need for a user to enter FI101 (e.g., the processing system 100 is configured so that there is no manual access within FI101).

[0018] In some embodiments, a gas flow (e.g., inert gas, nitrogen) is provided into one or more chambers (e.g., FI101) of processing system 100. In some embodiments, the gas flow is greater than leakage through one or more chambers to maintain a positive pressure in the one or more chambers. In some embodiments, the inert gas in FI101 is recirculated. In some embodiments, a portion of the inert gas is exhausted. In some embodiments, to maintain a positive pressure of the inert gas in FI101, the gas flow of gas that is not recirculated into FI101 is greater than the exhausted gas flow and gas leakage. In some embodiments, FI101 is coupled to one or more valves and / or pumps to provide gas flow into and out of FI101. A processing device (e.g., in controller 109) controls the gas flow into and out of FI101. In some embodiments, the processing device receives sensor data from one or more sensors (e.g., oxygen sensors, moisture sensors, motion sensors, door operation sensors, temperature sensors, pressure sensors, etc.) and determines the flow rate of inert gas into and out of FI101 based on the sensor data.

[0019] Enclosure system 130 is also capable of teaching, calibrating, and / or diagnosing a robotic arm (e.g., of a factory interface robot) without opening the sealed environment within FI 101 and adjacent chambers. Enclosure system 130 seals against load port 128 in response to docking thereon. Enclosure system 130 provides purge port access so that the interior of enclosure system 130 can be purged prior to opening enclosure system 130 to minimize disturbance of the inert environment within FI 101.

[0020] 2 illustrates a schematic diagram of a substrate processing system 200 that enables effective prevention of substrate contamination during pressure changes, according to some embodiments of the present disclosure. The electronic device processing system 200 includes an FI 101 (or equipment front-end module, EFEM), which interfaces with one or more substrate carriers, e.g., FOUPs (not shown). In addition, the FI 101 interfaces with a load lock chamber 104 via a first vacuum port 103. The load lock chamber 104 further interfaces with a transfer chamber 106 via a second vacuum port 105. The transfer chamber 106 provides access to one or more processing chambers (not depicted in FIG. 2 ). The FI 101 and the transfer chamber 106 include respective robots 111 and 112 for moving substrates 201, 202 between the FI 101, the load lock chamber 104, the transfer chamber 106, and the processing chambers.

[0021] The load lock chamber 104 includes various equipment for monitoring and controlling the environment therein. More specifically, the load lock chamber 104 has a dynamic valve 204 for setting a gas flow rate F(t) into (solid arrow) or out (dotted arrow) of the load lock chamber 104. The dynamic valve 204 is a fast-response valve capable of setting the flow rate F(t) continuously or quasi-continuously in response to an input control signal, as described in more detail below. The gas whose flow rate is controlled by the dynamic valve 204 can be nitrogen, argon, xenon, krypton, or any other suitable gas, e.g., a low-reactivity gas that does not react with the substrates 201 and 202. The setting of the dynamic valve 204 indirectly controls the pressure P(t) within the load lock chamber 104. The load lock chamber 104 has a pressure sensor 208 for monitoring the pressure within the load lock chamber 104. For simplicity, only one pressure sensor 208 is shown in the load lock chamber 104, however, multiple pressure sensors may be positioned at various locations in the load lock chamber 104. Various other sensors may also be used. For example, monitoring of the environment in the load lock chamber 104 may be performed using one or more temperature sensors to measure the temperature at one or more locations in the load lock chamber 104, using one or more chemical sensors to detect the presence (and / or concentration) of contaminants at various locations in the load lock chamber 104, using one or more optical sensing devices (e.g., to monitor the presence of contaminant particles), etc.

[0022] The substrate processing system 200 includes a computing device 210 for implementing the types of pump-up and pump-down variations according to the present disclosure. The computing device 210 can be a desktop computer, a laptop computer, a workstation, a wearable device (e.g., a tablet, a smartphone), a cloud-based computing service, or the like. In some embodiments, the computing device 210 is a dedicated microcontroller operating independently or in conjunction with another computing device. In some embodiments, the computing device 210 controls multiple stages of substrate manufacturing, including receiving substrates within the FI 101, delivering substrates to the transfer chamber 106 and processing chambers, performing various processes therein (e.g., masking, etching, deposition, imaging, quality control, etc.), and retrieving the substrates from the processing chambers after processing. In addition to the operations listed above, the computing device 210 performs many more specific functions related to monitoring and controlling the pressure inside the load lock chamber 104.

[0023] In particular, the computing device 210 has a pressure monitoring component 220, which collects pressure data (e.g., P LL The computing device 210 collects pressure monitoring module 220 (P(t)) and other data from the load lock chamber 104, including temperature data, optical sensor data, chemical sensor data, etc. The computing device 210 further includes a valve control module 222 to regulate the amount of gas flow 206 F(t) into (or out of) the load lock chamber 104 by providing a signal (e.g., analog or digital) to the dynamic valve 204. The pressure monitoring module 220 and the valve control module 222 operate in conjunction with pressure and flow modeling 224 to identify a target pressure P(t) and a target flow rate F(t) that represent a desired (e.g., optimal or near-optimal) type of change of the pump-down and / or pump-up process to be performed in the load lock chamber 104.

[0024] In one embodiment, the modules and components of the computing device operate as follows: In some embodiments, the computing device 210 executes a technological process involved in the substrate processing system 200. In other embodiments, the computing device 210 is aware of a technological process that some other computing device is controlling, and performs only a part of the overall process, for example, the computing device 210 controls the environment of the load lock chamber 104, sealing and opening the load lock chamber 104, etc., before and after completion of a pump-down / pump-up process. In some embodiments, the computing device 210 determines that the substrate 202 has undergone processing in one or more processing chambers and is ready to be moved from the transfer chamber 106 to one of the FOUPs docked to the FI 101. The computing device 210 then determines that in the current technological process, a given gas is heated at a pressure P T Finally, the computing device 210 determines that the opening of the load lock chamber 104 opens the first vacuum port 103, so that the current pressure in the load lock chamber 104 is equal to the factory interface pressure P I It is further determined that the pressure in the load lock chamber 104 is at or near P, which may be comparable to atmospheric pressure. Therefore, before the second vacuum port 105 can be opened for the passage of the substrate 202, the pressure in the load lock chamber 104 must be P I From P T The computing device 210 further determines that the pump-down process should be completed within a time τ. I ), final pressure (in this example, P T) and time τ are then input to pressure and flow modeling 224 for determination of a target pressure profile P(t) according to methods and techniques described below. Additionally, pressure and flow modeling 224 determines a target gas flow F(t) to be implemented by dynamic valve 204 to maintain the target pressure profile P(t). In some implementations, the determination by pressure and flow modeling 224 is performed prior to the start of the pump-down / pump-up process, and the target F(t) and P(t) are stored in memory of computing device 210.

[0025] Upon receiving instructions to implement a target flow rate F(t) and a target pressure P(t), e.g., from pressure and flow modeling 224 (or retrieving such instructions from memory pre-stored as target profiles F(t) and P(t)), the valve control module 222 outputs a control signal to the dynamic valve 204 to set and adjust the target flow rate F(t). In some implementations, the control signal is output continuously. For example, the valve control module 222 can output a current I(t) (or a voltage V(t)) to continuously control the flow rate through the dynamic valve 204. In some implementations, the valve control module 222 outputs a signal quasi-continuously, e.g., by varying the strength of the current (or voltage) signal every fraction Δτ of the total duration τ of the pump-down (or pump-up) process. In some implementations, the signal strength is varied multiple times over the entire duration (so that Δτ<<τ). Meanwhile, the pressure monitoring component 220 monitors the actual pressure P inside the load lock chamber 104 in real time. LL (t) is monitored, for example, the difference ΔP(t)=P LL The actual pressure is compared to the target pressure profile P(t) by calculating the difference ΔP(t)-P(t). Depending on the sign and magnitude of the difference ΔP(t), the valve control module 222 varies the signal output to the dynamic valve 204 to modify the gas flow 206 and increase the actual pressure P LL(t) approaches the target pressure P(t). For example, if ΔP(t)>0 is detected during the pump-down process, the valve control module 222 causes the dynamic valve 204 to increase the gas flow F(t) from the load lock chamber 104. Conversely, if ΔP(t)<0 is detected, the valve control module 222 causes the dynamic valve 204 to decrease the gas flow F(t). A similar process follows during the pump-up process. For example, if ΔP(t)>0 is detected during the pump-up process, the valve control module 222 causes the dynamic valve 204 to decrease the gas flow F(t) into the load lock chamber 104. Conversely, if ΔP(t)<0 is detected, the valve control module 222 causes the dynamic valve 204 to increase the gas flow F(t) into the load lock chamber 104.

[0026] Although the above examples and the remainder of the disclosure refer to processes performed to equalize pressure between the load lock chamber and the transfer chamber (pump-down phase) or between the load lock chamber and the factory interface (pump-up phase), the disclosed methods and systems are applicable to equalizing pressure between any two or more chambers of various manufacturing systems in particle-sensitive environments.

[0027] FIG. 3 schematically illustrates the type of change in pressure (upper graph) determined to minimize substrate contamination and the flow rate of gas into the load lock chamber (lower graph) during the pump-up phase of substrate fabrication, according to some implementations of the present disclosure. The illustrated pressure curve P(t) is further divided into three phases for ease of discussion. In Phase 1, the pressure in the load lock chamber is relatively low (P(t) is about 1 Torr or even lower). T(t)). When the pressure in the chamber is low, the probability of particle detachment (resuspension) from the surface is higher than when the pressure is high. In addition, when the pressure is low, the fast increase in pressure P(t) caused by a large flow rate of gas F(t) creates significant aerodynamic drag forces near the particles adsorbed on the surface, again making particle detachment more likely. For example, if the flow rate F(t) is expressed in units of volume per time (e.g., cm 3 For an adiabatic increase in pressure, dP(t) / dt = γP(t)F(t) / V, measured in sq. / s, where V is the chamber volume and γ is the adiabatic exponent (e.g., γ = 7 / 5 for molecular nitrogen), and for an isothermal increase, dP(t) / dt = P(t)F(t) / V. Thus, as seen by the bottom graph in Figure 3, Phase 1 is characterized by a relatively low (but continually increasing) flow rate F(t) and pressure P(t). Phase 1 (the "slow vent" phase) continues until some level of pressure P (Phase 2), depicted as P6 in Figure 3, is reached. In some embodiments, pressure P (Phase 2) is between 20 and 25 Torr, although pressure P (Phase 2) may vary depending on the volume of chamber V, the type of gas being used, the type and quality of chamber surfaces, the type of adsorbed particles that may be present in the chamber environment, etc. After pressure P (phase 2) is reached, the likelihood of resuspension decreases, and higher flow rates can be used without resuspending many additional particles. As a result, pressure P (phase 2) ("fast vent") begins. In some implementations, in phase 2, the flow rate increases relatively quickly to a maximum amount F max and then maintained at that level. In some implementations, the flow rate in Phase 2 is a maximum amount specified by a human (e.g., a systems engineer). In some embodiments, the maximum amount F max is calculated by pressure and flow modeling 224 based on a target duration τ of the pump-up process. In some embodiments, the target duration τ may be determined based on a target throughput (number of substrates processed in a specified time). In some embodiments, the maximum flow rate F maxis the ultimate flow rate F supported by the dynamic valve 204 and the valve control module 222 ult For example, F max / F ult = 0.8, 0.85, 0.9, etc. The limiting flow rate F ult Somewhat lower maximum flow rate F max is the actual pressure P LL (t) lags behind the target curve P(t), and F max In some implementations, when the pressure P(t) approaches a target pressure, e.g., when the pressure P(t) in the factory interface I Phase 3 (the "tail") begins when the flow rate F(t) approaches t. In Phase 3, the flow rate F(t) decreases smoothly but rapidly to the flow rate used in Phase 2 (e.g., maximum pressure F max ) to zero. For example, the duration of phase 3 is I the intended pressure P at the intended stage of time τ (counted from the start of the pumping process) without exceeding I For example, assume the time for shutting off the dynamic valve to be Δt (this time can be known from the valve specifications or can be determined through empirical testing), and set the average flow rate in phase 3 to F max / 2, the average increase in pressure in phase 3 (for isothermal pumping) is It can be estimated as TIFF0007772835000001.tif11170, where the pressure at the start of phase 3 is the final pressure P I Therefore, phase 3 begins once the pressure in the chamber reaches a value When TIFF0007772835000002.tif11170 is reached, it can begin. This example is intended as an illustration only, and many other flow rate profiles F(t) can be implemented with roughly the same goal of effective tailing of the pump-up process. The advantage of having Phase 3 is twofold. On the one hand, P(t) is the time when P I Even if the pressure exceeds P I On the other hand, phase 3 ensures that the pressure in the load lock chamber and the pressure in the factory interface are exactly equal, and opening the gate between the chambers does not disturb the environment of either chamber (as might otherwise happen if the two pressures were different).

[0028] In some embodiments, the flow rate F(t) is j (depicted by the black triangles and dotted line in the bottom graph of Figure 3), for example, the pressure in the chamber is set in a quasi-continuous fashion by specifying a distinct set of pressures P j (depicted by the black circle in the upper graph in Figure 3), j The flow rate F can be set by a dynamic valve in predetermined steps of several (e.g., as few as three to as many as several tens or more) j For example, as depicted in the non-limiting example in FIG. 3, thirteen different flow rates may be specified over the duration of the pump-up process, with values ​​F0 through F5 implementing Phase 1 (corresponding to target pressure values ​​P1 through P6), value F6 implementing Phase 2 (corresponding to target pressure values ​​P6 and P7), values ​​F7 through F8 implementing Phase 3 (corresponding to target pressure values ​​P8 and P9), and so on. 12 Phase 3 (intended pressure P I (leading to...)

[0029] 4 is a schematic diagram of an example algorithm 400 used to determine a target pressure and target flow rate for a pump-up process that reduces the presence of contaminants in a substrate processing system, according to some embodiments of the present disclosure. The example algorithm 400 can use multiple physical and statistical models to ensure accuracy of predictions under realistic modeling conditions. In some embodiments, the example algorithm 400 includes a drag force model 410 based on aerodynamic equations. In one example, the drag force model 410 uses gas particle size (e.g., diameter) and viscosity (e.g., dynamic or kinematic viscosity). The drag force model 410 determines the aerodynamic flow profile near a chamber surface (e.g., variation in flow velocity with distance from the surface) based on, for example, the gas viscosity, and further determines the force acting on particles adhered to the surface.

[0030] In some embodiments, the example algorithm 400 includes a surface adhesion model 420 that determines the amount of force that should be applied to a given particle to detach the particle from the surface. Particles are characterized by their size, density, and shape (e.g., spherical, ellipsoidal, rod-shaped, etc.). Surfaces are characterized by surface roughness, which can include variations in the lateral scale of the surface profile, the normal (orthogonal to the surface) scale of the surface profile, etc. The interaction of particles with surfaces can be modeled using various mechanisms. For example, in one mechanism, the adhesion of particles to a surface is modeled using a spring model.

[0031] In some embodiments, a static or dynamic model is used, in which the drag force is a varying, e.g., random, function of time that has a particular mean value (in the direction of gas flow) and a variation around that mean value (which is itself dependent on the average velocity of the gas flow).

[0032] In some embodiments, the output of the drag force model 410 (which characterizes the drag forces experienced by particles of various sizes) and the surface adhesion model 420 (which characterizes the conditions for particle detachment) are used to determine the probability of resuspension for a given particle (block 430). For example, a particle of a given size and placed in a given flow of gas (determined by a specified flow rate F(t) given a particular chamber geometry) will undergo a motion that has a particular probability of reaching the conditions for detachment from the surface. For example, the drag force calculated using the drag force 410 and applied as an input to the surface adhesion model 420 can result in a characteristic stretch Δl(t) of a spring as a function of time. Based on the probability that Δl(t) exceeds the threshold stretch for particle detachment, the probability of resuspension per unit time 430 is determined. In some embodiments, the probability of resuspension (detachment) p(F t / F d ) is (i) the threshold force F required to pull a particle from a surface t and (ii) the actual resistive force F acting on the particle. d and a function (e.g., a model function) that depends on the ratio of t / F d ) can be an exponential function, a power function, or some other function. In some embodiments, p(F t / F d ) is F t / F d approaches zero when is large (weak resistance), and F t / F d It increases when becomes smaller (strong resistance).

[0033] The probability of resuspension 430 can be determined for a particular particle (size, shape, etc.) and for a particular condition of the surface (adhesion energy, elastic properties of the surface, surface roughness, etc.). The probability of resuspension 430 may be used in statistical ensemble averaging 440. Inputs to statistical ensemble averaging 440 also include particle size distribution 450, surface roughness distribution 460, distribution of adhesion energy, etc. The statistical ensemble averaging applied to the probability of resuspension determines the average probability of resuspension for the ensemble or particles adhered to the surface of the chamber. Based on the statistical ensemble averaging 440, an integration over time is performed to determine the fraction of particles remaining 470 as a function of time.

[0034] In some embodiments, the fraction of remaining particles 470, e.g., η(t)=η[F(t), V, P T , P I ] is determined by considering the type of change in flow rate F(t) selected for the chamber, which is determined by the initial pressure (e.g., transfer chamber pressure) P T and the final pressure (e.g., factory interface pressure) P IDetermine the dynamics of the pressure P(t) in the chamber (with respect to the known volume V of the chamber), ending with . The various models and blocks of algorithm 400 can be repeated any number of times, for example, within time increments Δt. For each time increment, the updated conditions for resuspension can be recalculated based on the current pressure P(t) and the newly updated flow rate (F(t+Δt). The new resistance force and new resuspension probability are then determined by the respective blocks of algorithm 400, and statistical ensemble averaging 440 is performed to obtain the derivative of the remaining particle fraction, -Δη(t) / Δt. Based on the value of the derivative at each time increment, the final remaining particle fraction, η(τ), at the end of the pump-up process is determined. As a result, using simulations performed by blocks 410-470, flow rate and pressure optimization 480 identifies a target flow rate F(t) given a target duration τ and a target fraction of particles remaining adsorbed (attached to the surface), η(Target). The target fraction of particles depends on the particular technological process being performed (e.g., depending on the target quality of the product being manufactured) and can be 70%, 80%, 90%, or any other value.

[0035] 5 illustrates a schematic variation pattern of pressure (top graph) and flow rate of gas out of a load lock chamber (bottom graph) determined to minimize condensation of liquid during the pump-down phase of substrate fabrication, according to some embodiments of the present disclosure. A target pressure curve P(t) is illustrated, which may be determined as described below in connection with FIG. 6. The target pressure curve P(t) is a curve that is plotted against an initial pressure P I This may be the pressure in the factory interface, and the final pressure P T , which may be the pressure in the transfer chamber. The target flow rate F(t) for gas flow out of the load lock chamber (used to enforce the target pressure P(t)) is depicted schematically in the graph below, with the minus sign on the flow rate emphasizing that the gas flow is out of the chamber.

[0036] In some embodiments, the flow rate F(t) is determined, for example, at a predetermined stage t j A discrete set of flow rates F as set by the controller through a dynamic (continuous) valve at j It is set quasi-continuously by specifying the flow rate F (drawn by a dotted line with a black triangle). j is the pressure in the chamber that reaches the target pressure value P j (depicted by the black circles in the top graph of Figure 5). j The number of is at least three and may be as many as several dozen or more.

[0037] FIG. 6 schematically illustrates an example algorithm 600 used to determine a target pressure and a target flow rate during a pump-down process to reduce liquid condensation in a substrate processing system, according to some embodiments of the present disclosure. The example algorithm 600 can use various physical models to ensure accuracy of predictions under realistic modeling conditions. In some embodiments, the example algorithm 600 determines a pumping time constant (block 610), which may be the ratio of the chamber volume to the (instantaneous) flow rate F(t). Although referred to as a “constant,” the pumping time constant actually varies with changes in flow rate. In some embodiments, the example algorithm 600 further determines the chamber volume-to-surface ratio for the specific chamber being modeled (block 620). In some embodiments, the example algorithm 600 also determines a heat transfer coefficient (block 630). The heat transfer coefficient indicates how heat is efficiently exchanged between various regions of the chamber (e.g., via convective exchange).

[0038] The determined pumping time constant, chamber volume surface ratio, and heat transfer coefficient may be combined (block 640) into a dimensionless pumping rate Z. The dimensionless pumping rate is calculated based on the threshold humidity RH (for a given value of Z). T(Z) (at block 650). At block 660, the actual input relative humidity RH (at block 670) is compared to a threshold humidity. The target flow rate F(t) and target pressure P(t) are then used to determine whether the actual humidity is below the threshold humidity RH ≦ RH at various (e.g., all) stages of the pump-down process. T (Z) (block 680). In some embodiments, the target flow rate F(t) and target pressure P(t) are determined from the condition that the target flow rate F(t) remains below α RH T (Z), where for added safety a factor α<1 is used, such that α=0.95, 0.9, 0.85, etc. This additional safety factor can be used as a safety cushion to prevent condensation from forming in the event of an unexpected deviation of the pressure in the chamber from the target pressure (or various other variations in the chamber environment).

[0039] FIG. 7A illustrates an example valve control system 700 that can be used to prevent product contamination in a substrate processing system during pressure changes, according to some embodiments of the present disclosure. The valve control system 700 uses the same gas flow path during pump-down and pump-up processes. In some embodiments, the valve control system 700 achieves a target flow rate / pressure change type determined for a particular manufacturing process by algorithm 400 of FIG. 4 and / or algorithm 600 of FIG. 6 . FIG. 7A depicts the load lock chamber 104 receiving gas flow 706 from a pump 708 through a continuous (dynamic) valve 710 during the pump-up phase (the direction of gas flow 706 is reversed during the pump-down phase). A controller 720 controls the operation of the continuous valve 710. In various implementations, the continuous valve 710 can be a solenoid valve, a butterfly valve, or any other valve capable of continuous flow control. The controller 720 includes one or more processing devices, such as a central processing unit (CPU), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a digital signal processor (DSP), a network processor, etc. The processing device is communicatively coupled to one or more memory devices, such as a read-only memory (ROM), a flash memory, a static memory, a dynamic random access memory (DRAMA), etc. The controller 720 may be part of a desktop computer, a laptop computer, a workstation, a wearable device (e.g., a tablet, a smartphone, etc.), a cloud-based computing device, etc. In some embodiments, the controller 720 is a dedicated microcontroller configured to perform pump-up and / or pump-down processes in a substrate processing system. In some embodiments, the controller 720 is part of a larger network of computing devices. In some embodiments, an external computing device in communication with the controller 720 is capable of reconfiguring the controller 720 (e.g., changing settings, updating memory, or otherwise reprogramming it).

[0040] In one embodiment, the controller 720 outputs a control signal (e.g., an analog signal) to a power element 722, which provides a voltage or current input to the continuous valve 710. The input provided by the power element 722 changes an internal state of the continuous valve 710. For example, the current output by the power element 722 increases or decreases the magnetic field of a solenoid, thereby causing a magnetically actuated plunger to partially block an opening to modify the gas flow 706 to the desired extent. Various other dynamic valves (e.g., ball valves, butterfly valves, flap valves) are possible where continuous control of gas flow can be used instead of a solenoid valve. The power element 722 can include a battery, generator, capacitor, rechargeable battery, or any other source of current. The power element 722 can further include one or more circuit elements to enable precise control of the output current (or voltage), such as a current / voltage divider, stabilizer, bridge, feedback loop, ammeter, or voltmeter. In some embodiments, the power element 722 includes a DC source. In some embodiments, the power element 722 includes an AC source, which is further used in conjunction with a transformer, a rectifier, and other elements.

[0041] The controller 720 can exercise additional control over the continuous valve 710 using a valve gauge 724 (as indicated by the dotted arrow). The valve gauge 724 can be (or include) any sensor that collects data regarding conditions internal to the continuous valve 710. The valve gauge 724 can monitor (e.g., in real time) internal valve metrics indicative of obstruction of the gas flow 706 by the valve mechanism, which can include plunger position, flap angle, velocity of the gas flow 706 near the compressed region of the valve, etc. The valve gauge 724 serves as an additional check for the controller 720 to verify the setting of the continuous valve 710 and as part of a feedback loop to enhance the accuracy of the set gas flow 706. In one example, the controller 720 directs the power element 722 to output a current I to the continuous valve 710, causing the valve to allow a gas flow F(I) to pass therethrough. Meanwhile, the valve gauge 724 indicates that a flow rate F(I)-ΔF less than intended is being set by the valve gauge 724. The controller 720 then instructs the power element 722 to increase the current to I+ΔI (or decrease it to I−ΔI, depending on the valve design) to compensate for the deficit ΔF. In some examples, the compensation is achieved iteratively by incrementing or decrementing the current ΔI (or other signal) multiple times. In some embodiments, instead of (or in addition to) adjusting the signal output by the power element 722, the controller 720 adjusts the settings of the pump 708 to increase the gas flow pumped through the continuous valve 710.

[0042] In some embodiments, the secondary valve 726 provides additional control over the operation of the sequential valve 710, further improving the accuracy with which the rate of gas flow into the load lock chamber 104 is set. The secondary valve 726 can be utilized to control some additional aspect of the sequential valve 710, the gas flow 706, or the delivery system that delivers the gas flow 706. In some embodiments, the secondary valve 726 is packaged with the sequential valve 710, e.g., as part of the internal mechanism of the sequential valve 710. For example, the secondary valve 726 can control the size of the opening, the shape of the opening, the distance between the opening and the moving parts of the sequential valve 710, etc. In some embodiments, the secondary valve 726 is located external to the sequential valve 710. For example, the secondary valve 726 can be used to control the cross-sectional area of ​​the delivery line that delivers gas from the pump 708 to the sequential valve 710 or the cross-sectional area of ​​the delivery line that delivers gas from the sequential valve 710 to the load lock chamber 104. In some embodiments, secondary valve 726 is connected in parallel to sequential valve 710; e.g., secondary valve 726 controls gas flow through a bypass around sequential valve 710. In some embodiments, secondary valve 726 is also a sequential valve, such as, e.g., a proportional valve whose setting is determined proportionally to a signal from controller 720. In some embodiments, secondary valve 726 has several discrete settings. For example, when gas flow 706 is increased (or decreased), controller 720 causes secondary valve 726 to change the size (e.g., cross-section) of the opening in sequential valve 710 in a discontinuous manner (e.g., in increments of ΔA). At the same time, the control signal provided to sequential valve 710 is similarly discontinuously changed (e.g., the distance from the solenoid plunger to the opening is shortened) to compensate for the change in opening and ensure a continuous increase in gas flow rate despite the change in opening. The setting of secondary valve 726 then remains fixed for a period of time, so that the setting of continuous valve 710 changes continuously until the next change in another setting of secondary valve 726. This process is repeated until the stage (pump down or pump up) is complete.

[0043] Pressure sensor 208 enables overall control over the pump-up and pump-down processes described above in connection with Figures 3 and 5. Pressure readings from pressure sensor 208 received by controller 720 enable controller 720 to determine whether the pump-up or pump-down process is being performed according to a target profile P(t) identified as described in connection with Figures 4 and 6. Depending on whether the process is ahead or behind the target schedule, controller 720 increases or decreases the flow rate by adjusting the settings of continuous valve 710 and optionally secondary valve 726.

[0044] FIG. 7B illustrates another example valve control system 701 that can be used to prevent contamination of products in a substrate processing system during pressure changes, according to some embodiments of the present disclosure. The valve control system 701 uses different gas flow paths during pump-down and pump-up processes. As depicted schematically, during the pump-up phase, gas flow 716 to the load lock chamber 104 can be provided by a gas source 718, which can be (or can include) a pressurized gas container, a pump, and / or other suitable components and devices. The gas flow 716 can be controlled by any sequential valve, similar to the way the sequential valve 710 of the valve control system 700 depicted in FIG. 7A controls the gas flow 706 (e.g., using a power element 722 that receives a control signal from a controller 720). The sequential valve can be a solenoid valve 730 (as depicted), a proportional valve, a butterfly valve, or any other valve that allows for continuous (or quasi-continuous) adjustment of flow rate. The state of the solenoid valve 730 can be monitored by the controller 720 using a valve gauge 724.

[0045] During the pump-down phase, the controller 720 can close the solenoid valve 730 (or any other continuous valve) to stop the gas flow 716 from flowing into the load lock chamber 104. The controller 720 can initiate the gas flow 736 out of the load lock chamber 104 by having another continuous valve, such as a butterfly valve 732, control the gas flow 736. While the butterfly valve 732 is depicted in FIG. 7B , the gas flow 736 may also be controlled by, for example, a solenoid valve, a proportional valve, or any continuous valve capable of continuous (or quasi-continuous) adjustment of the flow rate. The gas flow 736 can be sustained by a pump 709, which can be isolated from the gas source 718. In some embodiments, the pump 709 can direct the gas flow to the gas source 718 to be reused during a subsequent pump-up phase. In some embodiments, the gas flow may be directed to an exhaust port (not shown) and not reused during the pump-up phase. The state of butterfly valve 732 can be set by power element 723, which is controlled by controller 720. Power element 723 can be separate from power element 722 (as depicted), or in some embodiments, power element 723 and power element 722 can be combined into a single power source. The state of butterfly valve 732 can be monitored by controller 720 using valve gauge 725. In some embodiments, additional (secondary) valves may be connected in parallel or in series with solenoid valve 730 and / or butterfly valve 732, as described in more detail above in connection with FIG. 7A .

[0046] 8-10 are flow diagrams of methods 800, 900, and 1000, respectively, for implementing effective contamination prevention during pressure changes in a substrate processing system. In some embodiments, methods 800, 900, and 1000 are performed using the systems and components shown in FIGS. 1, 2, and 7, or any combination thereof. In some embodiments, methods 800, 900, and 1000 are performed by computing device 210 of FIG. 2 or controller 720 of FIGS. 7A and 7B. Methods 800, 900, and 1000 may be performed by one or more processing units (e.g., CPUs and / or GPUs), which may include (or be in communication with) one or more memory devices. In some embodiments, methods 800, 900, and 1000 are performed by multiple processing threads (e.g., CPU threads and / or GPU threads), each thread performing one or more individual functions, routines, subroutines, or operations of the method. In some embodiments, the processing threads performing methods 800, 900, and 1000 are synchronized (e.g., using semaphores, critical areas, and / or other thread synchronization mechanisms). Alternatively, the processing threads performing methods 800, 900, and 1000 are performed asynchronously with respect to one another. The various operations of methods 800, 900, and 1000 are performed in a different order compared to the order shown in FIGS. 8-10. Some operations of the methods may occur simultaneously with other operations. In some embodiments, one or more operations shown in FIGS. 8-10 are not performed at all times.

[0047] 8 is a flow diagram of a method 800 for defining pressure changes that minimize the occurrence of contamination in a substrate processing system, according to some embodiments of the present disclosure. In some embodiments, method 800 defines pressure changes in a load lock chamber (LLC) of a substrate processing system (SPS), although it should be understood that method 800 (as well as methods 900 and 1000 described below) can also be used in connection with pressure changes in any other sealable chamber or compartment of an SPS.

[0048] At block 810, method 800 includes sealing a chamber (referred to herein as a first chamber) from an external environment, which may include any other chambers (e.g., second chambers) or compartments of the SPS adjacent to or otherwise coupled to the first chamber. For example, a gate separating the first chamber from the second chamber may be configured to selectively seal and open the first chamber from the second chamber. The gate may be communicatively connected to a controller that causes the gate to selectively seal and open the first chamber.

[0049] At block 820, the method 800 can include a processing device (e.g., using the systems and components depicted in FIGS. 7A and 7B ) continuously adjusting the flow of gas into the first chamber over a target time period. The target time period can be set by a user / operator of the SPS and / or specified by the technological process being performed using the SPS. Adjusting the flow rate of the gas can be facilitated by a valve (referred to herein as the first valve) configured to continuously adjust the flow of gas into the first chamber. The first valve can also be communicatively connected to a controller (e.g., directly or via intermediate electronic circuitry, which can include power elements or other electronic circuitry). In some implementations, the first valve is a proportional valve or any other valve that continuously adjusts the flow of gas therethrough, for example, in response to a continuous control signal input to the first valve. In one non-limiting example, the first valve comprises a coil (solenoid). The input signal (referred to herein as the first input signal) is configured to cause the coil to generate a magnetic field that varies continuously over a target time period.

[0050] In some embodiments, the system performing method 800 further includes a second valve configured to adjust an internal condition of the first valve, such as the opening of the first valve. The second valve can be used for additional adjustability of the first valve. More specifically, the controller causes the second valve to receive a second input signal configured to cause the second valve to adjust the opening of the first valve. In some embodiments, the first input signal and the second input signal are received simultaneously by the respective valves.

[0051] In some embodiments, for example, in the example pump-up process, the flow of gas into the first chamber, as regulated by the first valve, is set to increase from a relatively small value to a higher target flow rate after the pressure inside the first chamber exceeds the target pressure. The target pressure, e.g., 20-25 Torr, can depend on the volume and shape of the first chamber. The target pressure can be determined using experimental testing or simulation, or both, and can be based on observing a decrease in the rate of resuspension of adsorbed particles after the pressure increases above a certain value.

[0052] At block 830, the method 800 determines whether the pressure in the first chamber is adjusted to a time curve (e.g., P(t)) or a target pressure value (e.g., P(t)) determined to minimize the generation of one or more contaminants in the first chamber of the SPS. j In some embodiments, the actual pressure in the first chamber (e.g., P LLTo monitor how closely the pressure (t) closely follows the time curve (or time sequence of target pressure values), a system performing method 800 may further include a pressure sensor that continuously detects the pressure inside the first chamber and communicates the detected pressure to a controller. Upon receiving the detected pressure, the controller adjusts the first input signal to account for the communicated pressure. Additionally, a system performing method 800 may include a gauge that continuously detects the state of the first valve and communicates the detected state of the first valve to the controller. Upon receiving the detected state, the controller adjusts the first input signal to account for the communicated state of the first valve. The adjustment of the first input signal causes the pressure inside the first chamber of the SPS to follow the time curve (or time sequence of target pressure values) determined to minimize generation of one or more contaminants in the first chamber.

[0053] In some embodiments, the temporal sequence of target pressure values ​​is determined to reduce the degree of particle resuspension in the first chamber of the SPS during a first time period. For example, the first time period may be the duration of a pump-up process. In some embodiments, in addition to the pump-up process, method 800 is also used during a pump-down process. For example, during a second time period, the controller causes the first valve to receive a second input signal. The second input signal may be configured to cause the first valve to continuously adjust the flow of gas out of the first chamber of the SPS over the second time period. More specifically, the second input signal may be configured to cause the pressure inside the first chamber to follow a different temporal curve (or a different temporal sequence of target pressure values) determined to reduce condensation (aerosolization) in the first chamber of the SPS during the second time period.

[0054] FIG. 9 is a flow diagram of a method 900 for moving a substrate from a first compartment of an SPS to a second compartment of an SPS while minimizing exposure of the substrate to contaminants, according to some embodiments of the present disclosure. The term “compartment” refers to any chamber of the SPS or any other part or component of the SPS that may be isolated from other parts or components of the SPS. The movement of the substrate may occur through an intermediate third compartment (e.g., a load lock chamber, an air lock chamber, a transfer chamber, etc.). In block 910, the method 900 includes opening a first gate between the first compartment and the third compartment, e.g., between the transfer chamber and the load lock chamber. In block 920, the method 900 continues by moving the substrate from the first compartment to the third compartment. With the substrate in the third compartment, in block 930, the first gate is closed to isolate the third compartment from the first compartment, and in block 940, the second gate is controlled to isolate the third compartment from the second compartment. All or some of blocks 910-940 may be performed based on instructions from a processing device performing method 900. At block 950, method 900 includes the processing device initiating a flow of gas. In the case of a pump-up process, the flow of gas flows into the third compartment, while in the case of a pump-down process, the flow of gas flows out of the third compartment.

[0055] At block 960, the method 900 continues by causing the processing device to, for each of a plurality of times, cause the gas flow rate to have a target reference flow rate (RFR) for each of a plurality of RFRs. The plurality of RFRs can be determined based on modeling that minimizes generation of contaminant particles in the third compartment caused by the gas flow. Due to the gas flow, the pressure in the third compartment changes from an initial pressure to a final pressure. In one non-limiting example, during the pump-up process, the initial pressure is less than 10 Torr and the final pressure is greater than 700 Torr. Similarly, during the pump-down process, the initial pressure is greater than 700 Torr and the final pressure is less than 10 Torr.

[0056] The method 900 may then continue with the processing device opening the second gate (block 970) and moving the substrate from the third compartment to the second compartment (block 980) in response to the pressure in the third compartment changing from the initial pressure to the final pressure.

[0057] 10 is a flow diagram of a method 1000 for modeling types of pressure changes and types of flow rate changes that minimize contaminant generation in a substrate processing system, according to some embodiments of the present disclosure. Method 1000 may be performed by computing device 210 of FIG. 3 or any other computing device. Method 1000 may be performed in conjunction with method 800 of FIG. 8 and / or method 900 of FIG. 9. In some embodiments, method 1000 may be performed in real time, simultaneously with method 800 and / or method 900. In some embodiments, method 1000 may be performed prior to method 800 and / or method 900, with outputs of method 1000 (e.g., target pressure dynamics and target flow dynamics) being stored and subsequently used during the execution of method 800 and / or method 900.

[0058] In some embodiments, method 1000 determines a target pressure P(t) and a target flow rate F(t) for a pump-up phase of operation of a load lock chamber or any other compartment of a substrate processing system. At block 1010, method 1000 includes using a first model to characterize the drag force acting on a contaminant particle adsorbed to a surface of the chamber (e.g., the third compartment of method 900). In some embodiments, inputs to the first model include the viscosity (e.g., kinematic viscosity) of the gas, the velocity of the gas near the surface of the compartment, and various other parameters, such as parameters characterizing the geometry of the chamber (e.g., volume, area, and shape), the density of the gas, the temperature of the gas, the type of gas (monatomic, diatomic, etc.), etc. In some embodiments, the velocity of the gas near the surface of the chamber is determined based on the rate of gas flow into the chamber.

[0059] At block 1020, method 1000 continues by characterizing the affinity of the contaminant particle to the chamber surface using a second model. In some embodiments, the second model determines a threshold force for detachment of the contaminant particle from the chamber surface. The threshold force can depend on the radius of the contaminant particle, which is used as an input to the second model. Other inputs can include the strength of the attractive force (e.g., van der Waals interactions) between the contaminant particle and the chamber surface. For example, the strength of the attractive force may be parameterized using an adhesion energy that depends on the type of material of the contaminant particle, the radius (or any other dimension) of the contaminant particle, the roughness of the chamber surface, etc.

[0060] At block 1030, method 1000 continues by determining an instantaneous probability of resuspension of contaminant particles from the surface of the third compartment using the outputs of the first and second models. The instantaneous probability of resuspension refers to the probability that a contaminant particle (e.g., a particle of a particular size) will be resuspended from the surface given particular instantaneous values ​​of the gas pressure and temperature and the gas flow rate into the chamber. As the instantaneous values ​​change (e.g., over the duration of the pump-up process), the instantaneous probability of resuspension changes as well.

[0061] At block 1040, method 1000 continues by determining the percentage of contaminant particles remaining adsorbed to the chamber surfaces after the target duration of changing the pressure from the initial pressure to the final pressure. The operation of block 1040 can use the instantaneous probability (determined during the operation of block 1030) as an input and can further use the likely flow rate F1(t) (as well as the subsequent dynamics P1(t) of the pressure in the chamber) as an additional input. Various other likely flow rates F2(t), F3(t), ... (as well as the respective pressure dynamics P(t), P3(t), ...) can be used as other inputs. Different input flow rates can correspond to different durations of the pump-up process. Some processes may be relatively short (and therefore have relatively high maximum flow rates), while some processes may be longer (with correspondingly lower maximum flow rates). For each input, the processing device implementing method 1000 can calculate the percentage of contaminant particles remaining on the surface. For example, a shorter, and therefore more aggressive, pump-up process may have a smaller percentage of particles remaining adsorbed to the surface.

[0062] At block 1050, method 1000 continues with the processing device selecting a target change type for flow rate F(t) (and pressure P(t)) from a variety of possible input change types. In some embodiments, a continuous curve F(t) (and respective curves P(t)) can be selected. In other embodiments, a plurality of discrete target flow rates F(t1), F(t2), ... (reference flow rates) can be selected. The selected (continuous or discrete) flow rates F(t) (and pressure P(t)) can be stored for subsequent use in a pump-down process (e.g., as described in connection with methods 800 and 900 above). The (continuous or discrete) target flow rates are therefore determined based on (i) a target duration for changing the pressure in the chamber from an initial pressure to a final pressure, and (ii) a target percentage of contaminant particles that remain adsorbed on the chamber surfaces. The target percentage may depend on the details of the particular technology process being performed and the corresponding desire for the quality of the products (e.g., wafers) produced.

[0063] 11 depicts a block diagram of an example computing device 1100 operating in accordance with one or more aspects of the present disclosure. Computing device 1100 may be computing device 210 of FIG. 2, or controller 720 of FIGS. 7A and 7B, or any other processing device or combination of processing devices that perform method 800 of prescribing pressure changes to minimize generation of contaminants in a manufacturing system, method 900 of moving a substrate from a first compartment to a second compartment of an SPS, and / or method 1000 of modeling types of pressure and flow rate changes to minimize generation of contaminants in a substrate processing system.

[0064] The example computing device 1100 may be connected to other processing devices in a LAN, an intranet, an extranet, and / or the Internet. The computing device 1100 may be a personal computer (PC), a set-top box (STB), a server, a network router, a switch, or a bridge, or any device capable of executing a set of instructions (sequential or not) that specify actions that the device should take. Furthermore, although only a single example processing device is illustrated, the term "processing device" should also be interpreted to include any collection of processing devices (e.g., computers) that individually or jointly execute a set (or sets) of instructions to perform any one or more of the methodologies discussed herein.

[0065] An example computing device 1100 may include a processing device 1102 (e.g., a CPU), a main memory (e.g., read-only memory (ROM), flash memory, dynamic random access memory (DRAMA) such as synchronous DRAM (SDRAM), etc.), a static memory 1106 (e.g., flash memory, static random access memory (SRAM), etc.), and a secondary memory (e.g., a data storage device 1108), which may communicate with each other via a bus 1130.

[0066] The processing device 1102 represents one or more general-purpose processing devices, such as a microprocessor, a central processing unit, or the like. More specifically, the processing device 1102 may be a complex instruction set computing (CISC) microprocessor, a reduced instruction set computing (RISC) microprocessor, a very long instruction word (VLIW) microprocessor, a processor implementing other instruction sets, or a processor implementing a combination of instruction sets. The processing device 1102 may also be one or more special-purpose processing devices, such as an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a digital signal processor (DSP), a network processor, or the like. According to one or more aspects of the present disclosure, the processing device 1102 may include processing logic 1126 that may be configured to execute instructions implementing the method 800 for prescribing pressure changes to minimize contaminant generation in a manufacturing system, the method 900 for moving a substrate from a first compartment to a second compartment of an SPS, and / or the method 1000 for modeling types of pressure and flow rate changes to minimize contaminant generation in a substrate processing system.

[0067] The example computing device 1100 may further include a network interface device 1108, which may be communicatively connected to a network 1120. The example computing device 1100 may further include a video display 1110 (e.g., a liquid crystal display (LCD), touch screen, or cathode ray tube (CRT)), an alphanumeric input device 1112 (e.g., a keyboard), an input control device 1114 (e.g., a cursor control device, a touch screen control device, a mouse), and a signal generation device 1116 (e.g., an audio speaker).

[0068] The data storage device 1118 may include a computer-readable storage medium (or more specifically, a non-transitory computer-readable storage medium) 1128 on which one or more sets of executable instructions 1122 are stored. According to one or more aspects of the present disclosure, the executable instructions 1122 may include executable instructions for implementing the method 800 for prescribing pressure changes to minimize generation of contaminants in a manufacturing system, the method 900 for moving a substrate from a first compartment to a second compartment of an SPS, and / or the method 1000 for modeling types of pressure and flow rate changes to minimize generation of contaminants in a substrate processing system.

[0069] The executable instructions 1122 may also reside completely or at least partially within the main memory 1104 and / or the processing device 1102 during execution thereof by the example computing device 1100, the main memory 1104 and the processing device 1102. The executable instructions 1122 may further be transmitted or received over a network via the network interface device 1108.

[0070] Although computer-readable storage medium 1128 is shown in FIG. 11 as a single medium, the term "computer-readable storage medium" should be interpreted to include a single medium or multiple media (e.g., centralized or distributed databases, and / or associated caches and servers) that store one or more sets of operating instructions. The term "computer-readable storage medium" should also be interpreted to include any medium that can store or encode a set of instructions for execution by a machine that cause the machine to perform any one or more of the methodologies described herein. The term "computer-readable storage medium" should therefore be interpreted to include, but is not limited to, solid-state memory, and optical and magnetic media.

[0071] The following examples illustrate further implementations according to the present disclosure.

[0072] In Example 1, a system includes a load lock chamber (LLC) of a substrate processing system, the load lock chamber (LLC) including one or more valves that regulate the flow of gas induced to flow into or out of the LLC, and a controller configured to initiate the flow of gas through the one or more valves while the LLC is sealed from an external environment, and to match the gas flow rate to a respective RFR of a plurality of reference flow rates (RFRs) at each of a plurality of times, the plurality of RFRs including at least three RFRs, determined to minimize generation of one or more contaminants in an environment of the LLC.

[0073] In Example 2, in the system of Example 1, multiple RFRs are determined taking into account the initial pressure, the final pressure, and the target duration of the transition of the LLC's environment from the initial pressure to the final pressure.

[0074] In Example 3, in the system of Example 1, one or more contaminants appear in the LLC environment during transition of the LLC environment from an initial pressure to a final pressure.

[0075] In Example 4, the system of Example 3 further includes a pressure sensor communicatively connected to the controller, wherein the controller is further configured to receive a current pressure reading from the pressure sensor, obtain a difference between the received current pressure reading and each of a plurality of reference pressure values, each reference pressure value corresponding to a current stage of time, and adjust the rate of gas flow through the one or more valves to mitigate the obtained difference.

[0076] In Example 5, in the system of Example 1, the one or more valves are configured to continuously regulate the flow of gas.

[0077] In Example 6, in the system of Example 1, a gas flow is directed into the LLC and multiple RFRs are selected to minimize resuspension of particulate matter from the interior surface of the LLC within the LLC environment.

[0078] In Example 7, in the system of Example 1, the gas flow is directed out of the LLC, and multiple RFRs are selected to prevent aerosol formation within the environment of the LLC.

[0079] In Example 8, a system includes a substrate processing system (SPS) including a first chamber and a second chamber; a first gate configured to selectively seal and open the SPS first chamber from the SPS second chamber; a first valve configured to continuously adjust a flow of gas into the SPS first chamber; and a controller communicatively connected to the first gate and the first valve, the controller configured to cause the first gate to seal the SPS first chamber from the SPS second chamber and to cause the first valve to receive a first input signal, the first input signal causing the first valve to continuously adjust the flow of gas into the SPS first chamber over a first time period.

[0080] In Example 9, in the system of Example 8, the first input signal is configured to cause the pressure inside the first chamber of the SPS to follow a temporal sequence of target pressure values.

[0081] In Example 10, in the system of Example 9, a temporal sequence of target pressure values ​​is determined to reduce the degree of particle resuspension in the first chamber of the SPS during a first time period.

[0082] In Example 11, in the system of Example 8, the controller is further configured to cause the first valve to receive a second input signal, the second input signal causing the first valve to continuously adjust the flow of gas out of the first chamber of the SPS over a second time period.

[0083] In Example 12, in the system of Example 11, the second input signal is configured to cause the pressure inside the first chamber of the SPS to follow a time sequence of target pressure values, and the time sequence of target pressure values ​​is determined to reduce condensation in the first chamber of the SPS during a second time period.

[0084] In Example 13, in the system of Example 8, the first valve is a proportional valve.

[0085] In Example 14, in the system of Example 13, the first valve includes a coil, and the first input signal is configured to cause the coil to generate a magnetic field that varies continuously over a first time period.

[0086] In Example 15, the system of Example 8 further includes a second valve configured to adjust an opening of the first valve, and the controller is further configured to cause the second valve to receive a second input signal, the second input signal configured to cause the second valve to adjust the opening of the first valve.

[0087] In Example 16, in the system of Example 8, the flow of gas into the first chamber of the SPS over a first time period is increased to a target flow rate after the pressure inside the first chamber of the SPS exceeds the target pressure.

[0088] In Example 17, the system of Example 8 further includes a pressure sensor that continuously detects the pressure inside the first chamber of the SPS and transmits the detected pressure to the controller, and the controller is configured to adjust the first input signal taking into account the transmitted pressure.

[0089] In Example 18, in the system of Example 17, the first input signal is adjusted to cause the pressure inside the first chamber of the SPS to follow a time curve determined to minimize the generation of one or more contaminants in the first chamber of the SPS.

[0090] In Example 19, in the system of Example 8, the first valve includes a gauge that continuously detects a state of the first valve and communicates the detected state of the first valve to the controller, and the controller is configured to adjust the first input signal taking into account the communicated state of the first valve.

[0091] In Example 20, in the system of Example 8, the SPS further includes a second gate configured to selectively seal and open the first chamber of the SPS from the third chamber of the SPS and a second valve configured to continuously adjust the flow of gas flowing out of the first chamber of the SPS, and the controller is further configured to be communicatively connected to the second gate and the second valve, and to cause the second gate to seal the first chamber of the SPS from the third chamber of the SPS and to cause the second valve to receive a first input signal, which is configured to cause the second valve to continuously adjust the flow of gas flowing out of the first chamber of the SPS over a second time period.

[0092] In Example 21, a method includes sealing a chamber of a substrate processing system (SPS) from an external environment, continuously adjusting a flow of gas into or out of the chamber over a target time period, and causing the pressure in the chamber of the SPS to follow a time curve determined to minimize generation of one or more contaminants in the chamber of the SPS.

[0093] In Example 22, a method for moving a substrate from a first compartment of a substrate processing system (SPS) to a second compartment of the SPS includes opening a first gate between the first and third compartments of the SPS, moving the substrate from the first compartment to the third compartment, closing the first gate to isolate the third compartment from the first compartment, controlling the second gate to isolate the third compartment from the second compartment, and initiating a gas flow, wherein the gas flow is one of (i) a gas flow into the third compartment or (ii) a gas flow out of the third compartment. and causing the gas flow rate to have a respective target reference flow rate (RFR) for a plurality of RFRs at each of a plurality of times, the plurality of RFRs having respective target reference flow rates (RFR) for the plurality of RFRs determined based on modeling that minimizes generation of contaminant particles in the third compartment caused by the gas flow; and in response to a pressure change in the third compartment from an initial pressure to a final pressure, opening a second gate and moving the substrate from the third compartment to the second compartment.

[0094] In Example 23, the method of Example 22, wherein the gas flow is directed to a third compartment, and the modeling includes a first model that characterizes a drag force acting on a contaminant particle adsorbed to a surface of the third compartment.

[0095] In Example 24, in the method of Example 23, the inputs to the first model include a viscosity of the gas and a velocity of the gas near a surface of the third compartment, and the velocity of the gas is determined based on a rate of gas flow into the third compartment.

[0096] In Example 25, the method of Example 23, wherein the modeling includes a second model that characterizes the affinity of the contaminant particles for the surface of the third compartment.

[0097] In Example 26, the method of Example 25, wherein the modeling includes using outputs of the first model and the second model to determine an instantaneous probability of resuspension of contaminant particles from the surface of the third compartment.

[0098] In Example 27, the method of Example 23, wherein the modeling includes determining a percentage of contaminant particles that remain adsorbed to the surface of the third compartment after a target duration during which the pressure in the third compartment is changed from the initial pressure to the final pressure.

[0099] In Example 28, the method of Example 23 further determines the plurality of RFRs based on (i) a target duration for changing the pressure in the third compartment from the initial pressure to the final pressure, and (ii) a target fraction of contaminant particles that remain adsorbed on the surface of the third compartment.

[0100] In Example 29, the method of Example 22, wherein the initial pressure is one of a first pressure less than 10 Torr or a second pressure greater than 700 Torr, and the final pressure is another one of the first pressure less than 10 Torr or the second pressure greater than 700 Torr.

[0101] In Example 30, the method of Example 22, wherein the gas stream exits the third compartment and the contaminants are water particles.

[0102] In Example 31, the method of Example 30, wherein the modeling includes determining a threshold pressure for each of a plurality of threshold pressures associated with condensation of water particles at each of a plurality of times.

[0103] In Example 32, the method of Example 31, wherein each of the respective target RFRs is at or below a respective threshold pressure.

[0104] In Example 33, a system includes a substrate processing system including a first compartment, a second compartment, and a third compartment; a first gate isolating the third compartment from the first compartment; a second gate isolating the third compartment from the second compartment; a valve configured to adjust a flow of gas into the third compartment, where the flow of gas is one of (i) a flow of gas into the third compartment or (ii) a flow of gas out of the third compartment; and a valve configured to start the flow of gas, where the flow of gas is one of (i) a flow of gas into the third compartment or (ii) a flow of gas out of the third compartment. ii) one of the gas flows flowing out of the third compartment, causing the gas flow rate to have a target RFR for each of a plurality of reference flow rates (RFRs), the plurality of RFRs being determined based on modeling that minimizes the generation of contaminant particles in the third compartment caused by the gas flow; and a controller configured to open the first gate and the second gate as the pressure in the third compartment changes from an initial pressure to a final pressure, so that the substrate is moved from the first compartment to the second compartment via the third compartment.

[0105] In Example 34, in the system of Example 33, the gas flow flows into a third compartment, and the modeling includes a first model that characterizes the drag force acting on contaminant particles adsorbed on the surface of the third compartment.

[0106] In Example 35, in the system of Example 34, the modeling includes a second model that characterizes the affinity of the contaminant particles for the surface of the third compartment.

[0107] In Example 36, in the system of Example 33, the gas flow exits the third compartment, the contaminants are water particles, and the modeling includes determining a threshold pressure for each of a plurality of threshold pressures associated with condensation of the water particles at each of a plurality of times.

[0108] In Example 37, in the system of Example 36, each of the respective target RFRs is at or below a respective threshold pressure.

[0109] In Example 38, a non-transitory computer-readable memory storing instructions, when executed by a processing device, causes the processing device to: cause a first gate to isolate a first compartment of a substrate processing system (SPS) from a second compartment of the SPS; cause a second gate to isolate a third compartment of the SPS from the second compartment of the SPS; start a flow of gas, the flow of gas being one of (i) a flow of gas into the second compartment or (ii) a flow of gas out of the second compartment, the gas flow rate having a target reference flow rate (RFR) for each of a plurality of RFRs at each of a plurality of times, the plurality of RFRs being determined based on modeling that minimizes generation of contaminant particles in the second compartment caused by the flow of gas; and, in response to a pressure change in the third compartment from an initial pressure to a final pressure, open the first gate and the second gate and move the substrate from the first compartment to the third compartment via the second compartment.

[0110] In Example 39, in the non-transitory computer-readable memory of Example 38, the gas flow flows into a second compartment, and the modeling includes a first model characterizing a resistance force acting on a contaminant particle adsorbed to a surface of the second compartment, and a second model characterizing an affinity of the contaminant particle for the surface of the second compartment.

[0111] In Example 40, in the non-transitory computer-readable memory of Example 38, the flow of gas exits the second compartment, the contaminant particles are water particles, and the modeling includes determining, at each of a plurality of times, a threshold pressure for each of a plurality of threshold pressures associated with condensation of the water particles.

[0112] It should be understood that the above description is intended to be illustrative, and not limiting. Many other exemplary implementations will be apparent to those skilled in the art upon reading and understanding the above description. While the present disclosure describes specific embodiments, it should be understood that the systems and methods of the present disclosure are not limited to the embodiments described herein, but may be practiced with modification within the scope of the appended claims. Accordingly, the specification and drawings should be regarded in an illustrative, and not a restrictive, sense. The scope of the present disclosure should therefore be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

[0113] The method, hardware, software, firmware, or code implementations described above may be implemented via instructions or code stored on a machine-accessible, machine-readable, computer-accessible, or computer-readable medium that is executable by a processing element. "Memory" includes any mechanism that provides (i.e., stores and / or transmits) information in a form readable by a machine, such as a computer or electronic system. For example, "memory" includes random access memory (RAM), such as static RAM (SRAM) or dynamic RAM (DRAM), ROM, magnetic or optical storage media, flash memory devices, electrical storage devices, optical storage devices, acoustic storage devices, and any type of tangible machine-readable medium suitable for storing or transmitting electronic instructions or information in a form readable by a machine (e.g., a computer).

[0114] References throughout this specification to "one embodiment" or "an embodiment" mean that a particular feature, structure, or characteristic described in connection with this embodiment is included in at least one embodiment of the present disclosure. Thus, the appearances of the phrase "in one embodiment" or "in an embodiment" in various places throughout this specification do not necessarily all refer to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0115] In the foregoing specification, the detailed description has been provided with reference to specific example embodiments. It will be apparent, however, that various modifications and changes may be made thereto without departing from the broader spirit and scope of the present disclosure as set forth in the appended claims. The specification and drawings are, therefore, to be regarded in an illustrative and not a restrictive sense. Furthermore, the above-mentioned uses of embodiment, embodiment, and / or other exemplary terms do not necessarily refer to the same embodiment or the same example, but may refer to different and distinct embodiments, and may also, in some cases, refer to the same embodiment.

[0116] The words "example" or "exemplary" are used herein to mean serving as an example, instance, or illustration. Any aspect or design described herein as "example" or "exemplary" should not necessarily be construed as preferred or advantageous over other aspects or designs. Rather, the words "example" or "exemplary" are intended to present concepts in a practical manner. As used in this application, the term "or" is intended to mean an inclusive "or" rather than an exclusive "or." That is, unless otherwise specified or clear from the context, "X includes A or B" is intended to mean any of the natural inclusive permutations. That is, if X includes A, X includes B, or X includes both A and B, then "X includes A or B" is satisfied under any of the above examples. Additionally, the articles "a" and "an," as used in this application and in the appended claims, should be interpreted broadly to mean "one or more," unless otherwise specified or clearly dictated by the context. Furthermore, use of the terms "one embodiment" or "one implementation" or "one embodiment" or "one embodiment" throughout is not intended to refer to the same embodiment or embodiments unless so stated. Also, the terms "first," "second," "third," "fourth," etc., as used herein, are intended as labels to distinguish between different elements and do not necessarily have a meaning that denotes an order according to their numerical designation. The present application also includes the following aspects. (Aspect 1) a load lock chamber (LLC) of a substrate processing system having one or more valves for regulating the flow of gases directed into or out of the LLC; a controller, initiating the flow of gas through the one or more valves while the LLC is sealed from the external environment; The flow rate of gas is matched to a respective RFR of a plurality of reference flow rates (RFRs) at each of a plurality of times, the plurality of RFRs including at least three RFRs, and the RFRs are determined to minimize generation of one or more contaminants in an environment of the LLC. and a controller configured to: (Aspect 2) 2. The system of claim 1, wherein the plurality of RFRs are determined taking into account an initial pressure, a final pressure, and a target duration of transition of the environment of the LLC from the initial pressure to the final pressure. (Aspect 3) 2. The system of claim 1, wherein the one or more contaminants appear in the environment of the LLC during a transition of the environment of the LLC from an initial pressure to a final pressure. (Aspect 4) a pressure sensor communicatively connected to the controller, the controller further comprising: receiving a current pressure reading from the pressure sensor; obtaining a difference between the received current pressure reading and each of a plurality of reference pressure values, each of the reference pressure values ​​corresponding to a current time; adjusting the rate of flow of gas through the one or more valves to mitigate the obtained difference; The system of embodiment 3, configured as follows: (Aspect 5) 2. The system of embodiment 1, wherein the one or more valves are configured to continuously regulate the flow of gas. (Aspect 6) 2. The system of claim 1, wherein the flow of gas is directed into the LLC and the plurality of RFRs are selected to minimize resuspension of particulate matter from an inner surface of the LLC within the environment of the LLC. (Aspect 7) 2. The system of claim 1, wherein the flow of gas is directed to flow out of the LLC and the plurality of RFRs are selected to prevent aerosol formation within the environment of the LLC. (Aspect 8) a substrate processing system (SPS) including a first chamber and a second chamber; a first gate configured to selectively seal and open the second chamber of the SPS from the first chamber of the SPS; a first valve configured to continuously regulate the flow of gas into the first chamber of the SPS; a controller communicatively connected to the first gate and the first valve, causing the first gate to seal the first chamber of the SPS from the second chamber of the SPS; a controller configured to cause the first valve to receive a first input signal, the first input signal causing the first valve to continuously adjust the flow of gas into the first chamber of the SPS over a first time period. (Aspect 9) 9. The system of embodiment 8, wherein the first input signal is configured to cause the pressure within the first chamber of the SPS to follow a temporal sequence of target pressure values. (Aspect 10) A system as described in aspect 9, wherein the temporal sequence of the target pressure values ​​is determined to reduce the degree of particle resuspension within the first chamber of the SPS during the first time period. (Aspect 11) The system of aspect 8, wherein the controller is further configured to cause the first valve to receive a second input signal, the second input signal causing the first valve to continuously adjust the flow of gas out of the first chamber of the SPS over a second time period. (Aspect 12) the second input signal is configured to cause the pressure within the first chamber of the SPS to follow a temporal sequence of target pressure values; 12. The system of claim 11, wherein the temporal sequence of the target pressure values ​​is determined to reduce condensation in the first chamber of the SPS during the second time period. (Aspect 13) 9. The system of claim 8, wherein the first valve is a proportional valve. (Aspect 14) 14. The system of claim 13, wherein the first valve comprises a coil, and the first input signal is configured to cause the coil to generate a continuously varying magnetic field over the first time period. (Aspect 15) The system of aspect 8, further comprising a second valve configured to adjust the opening of the first valve, wherein the controller is further configured to cause the second valve to receive a second input signal, the second input signal being configured to cause the second valve to adjust the opening of the first valve. (Aspect 16) A system as described in aspect 8, wherein the flow of gas flowing into the first chamber of the SPS over the first time period is increased to a target flow rate after the pressure inside the first chamber of the SPS exceeds a target pressure. (Aspect 17) The system of aspect 8, further comprising a pressure sensor that continuously detects the pressure inside the first chamber of the SPS and transmits the detected pressure to the controller, the controller being configured to adjust the first input signal taking into account the transmitted pressure. (Aspect 18) A system as described in aspect 17, wherein the first input signal is adjusted to cause the pressure inside the first chamber of the SPS to follow a time curve determined to minimize the generation of one or more contaminants within the first chamber of the SPS. (Aspect 19) The system of aspect 8, wherein the first valve comprises a gauge that continuously detects a state of the first valve and communicates the detected state of the first valve to the controller, and the controller is configured to adjust the first input signal taking into account the communicated state of the first valve. (Aspect 20) The SPS is a second gate configured to selectively seal and open the first chamber of the SPS from a third chamber of the SPS; a second valve configured to continuously regulate the flow of gas out of the first chamber of the SPS; the controller is communicatively connected to the second gate and the second valve, and further causing the second gate to seal the first chamber of the SPS from the third chamber of the SPS; causing the second valve to receive a first input signal, the first input signal configured to cause the second valve to continuously adjust the flow of gas out of the first chamber of the SPS over a second time period; The system of embodiment 8, configured as follows: (Aspect 21) 1. A method of moving a substrate from a first compartment of a substrate processing system (SPS) to a second compartment of the SPS, comprising: opening a first gate between the first compartment and the third compartment of the SPS; moving the substrate from the first compartment to the third compartment; closing the first gate to isolate the third compartment from the first compartment; controlling a second gate to isolate the third compartment from the second compartment; initiating a flow of gas, the flow of gas being one of: (i) a flow of gas into the third compartment; or (ii) a flow of gas out of the third compartment; causing the flow rate of the gas to have a respective RFR of a plurality of target reference flow rates (RFRs) at each of a plurality of times, the plurality of RFRs being determined based on modeling that minimizes generation of contaminant particles in the third compartment caused by the flow of the gas; and in response to a pressure change in the third compartment from an initial pressure to a final pressure, opening the second gate and moving the substrate from the third compartment to the second compartment. (Aspect 22) The flow of the gas flows into the third compartment, and the modeling uses a first model that characterizes drag forces acting on contaminant particles adsorbed on a surface of the third compartment, and inputs to the first model include: the viscosity of the gas; A method according to aspect 21, comprising: a velocity of the gas near the surface of the third compartment, wherein the velocity of the gas is determined based on the rate of the flow of the gas flowing into the third compartment. (Aspect 23) The modeling uses a second model that characterizes an affinity of the contaminant particles for the surface of the third compartment, the modeling comprising: determining an instantaneous probability of resuspension of the contaminant particles from the surface of the third compartment using outputs of the first model and the second model; A method as described in aspect 22, comprising determining the percentage of the contaminant particles that remain adsorbed to the surface of the third compartment after a target duration during which the pressure in the third compartment is changed from the initial pressure to the final pressure. (Aspect 24) 23. The method of claim 22, wherein the plurality of RFRs are further determined based on (i) a target duration for changing the pressure in the third compartment from the initial pressure to the final pressure, and (ii) a target fraction of contaminant particles that remain adsorbed to the surface of the third compartment. (Aspect 25) The flow of gas exits the third compartment, the contaminants are water particles, and the modeling 22. The method of claim 21, comprising determining a respective threshold pressure of a plurality of threshold pressures associated with condensation of the water particles at each of the plurality of times.

Claims

1. A substrate processing system (SPS) including a first chamber and a second chamber; a first gate configured to selectively seal and open the second chamber of the SPS from the first chamber of the SPS; a first valve configured to continuously regulate the flow of gas into the first chamber of the SPS; a controller communicatively connected to the first gate and the first valve, causing the first gate to seal the first chamber of the SPS from the second chamber of the SPS; a controller configured to cause the first valve to receive a first input signal, the first input signal causing the first valve to continuously adjust the flow of gas into the first chamber of the SPS over a first period of time; The system, wherein the first input signal is configured to cause the pressure within the first chamber of the SPS to follow a temporal sequence of target pressure values.

2. The system of claim 1 , wherein the temporal sequence of the target pressure values ​​is determined to reduce a degree of particle resuspension within the first chamber of the SPS during the first time period.

3. 10. The system of claim 1, wherein the controller is further configured to cause the first valve to receive a second input signal, the second input signal causing the first valve to continuously adjust the flow of gas out of the first chamber of the SPS over a second period of time.

4. the second input signal is configured to cause the pressure within the first chamber of the SPS to follow a temporal sequence of target pressure values; The system of claim 3 , wherein the temporal sequence of the target pressure values ​​is determined to reduce condensation within the first chamber of the SPS during the second time period.

5. A substrate processing system (SPS) including a first chamber and a second chamber; a first gate configured to selectively seal and open the second chamber of the SPS from the first chamber of the SPS; a first valve configured to continuously regulate the flow of gas into the first chamber of the SPS; a controller communicatively connected to the first gate and the first valve, causing the first gate to seal the first chamber of the SPS from the second chamber of the SPS; a controller configured to cause the first valve to receive a first input signal, the first input signal causing the first valve to continuously adjust the flow of gas into the first chamber of the SPS over a first period of time; the first valve is a proportional valve; The system, wherein the first valve comprises a coil, and the first input signal is configured to cause the coil to generate a continuously varying magnetic field over the first time period.

6. A substrate processing system (SPS) including a first chamber and a second chamber; a first gate configured to selectively seal and open the second chamber of the SPS from the first chamber of the SPS; a first valve configured to continuously regulate the flow of gas into the first chamber of the SPS; a controller communicatively connected to the first gate and the first valve, causing the first gate to seal the first chamber of the SPS from the second chamber of the SPS; a controller configured to cause the first valve to receive a first input signal, the first input signal causing the first valve to continuously adjust the flow of gas into the first chamber of the SPS over a first period of time; a second valve configured to adjust an opening of the first valve, wherein the controller is further configured to cause the second valve to receive a second input signal, the second input signal configured to cause the second valve to adjust the opening of the first valve.

7. A substrate processing system (SPS) including a first chamber and a second chamber; a first gate configured to selectively seal and open the second chamber of the SPS from the first chamber of the SPS; a first valve configured to continuously regulate the flow of gas into the first chamber of the SPS; a controller communicatively connected to the first gate and the first valve, causing the first gate to seal the first chamber of the SPS from the second chamber of the SPS; a controller configured to cause the first valve to receive a first input signal, the first input signal causing the first valve to continuously adjust the flow of gas into the first chamber of the SPS over a first period of time; The flow of gas into the first chamber of the SPS over the first time period is increased to a target flow rate after the pressure within the first chamber of the SPS exceeds a target pressure.

8. A substrate processing system (SPS) including a first chamber and a second chamber; a first gate configured to selectively seal and open the second chamber of the SPS from the first chamber of the SPS; a first valve configured to continuously regulate the flow of gas into the first chamber of the SPS; a controller communicatively connected to the first gate and the first valve, causing the first gate to seal the first chamber of the SPS from the second chamber of the SPS; a controller configured to cause the first valve to receive a first input signal, the first input signal causing the first valve to continuously adjust the flow of gas into the first chamber of the SPS over a first period of time; a pressure sensor that continuously detects a pressure within the first chamber of the SPS and communicates the detected pressure to the controller, the controller being configured to adjust the first input signal taking into account the communicated pressure; The system, wherein the first input signal is adjusted to cause the pressure within the first chamber of the SPS to follow a time curve determined to minimize generation of one or more contaminants within the first chamber of the SPS.

9. A substrate processing system (SPS) including a first chamber and a second chamber; a first gate configured to selectively seal and open the second chamber of the SPS from the first chamber of the SPS; a first valve configured to continuously regulate the flow of gas into the first chamber of the SPS; a controller communicatively connected to the first gate and the first valve, causing the first gate to seal the first chamber of the SPS from the second chamber of the SPS; a controller configured to cause the first valve to receive a first input signal, the first input signal causing the first valve to continuously adjust the flow of gas into the first chamber of the SPS over a first period of time; the first valve comprises a gauge that continuously senses a state of the first valve and communicates the sensed state of the first valve to the controller, the controller being configured to adjust the first input signal taking into account the communicated state of the first valve.

10. A substrate processing system (SPS) including a first chamber and a second chamber; a first gate configured to selectively seal and open the second chamber of the SPS from the first chamber of the SPS; a first valve configured to continuously regulate the flow of gas into the first chamber of the SPS; a controller communicatively connected to the first gate and the first valve, causing the first gate to seal the first chamber of the SPS from the second chamber of the SPS; a controller configured to cause the first valve to receive a first input signal, the first input signal causing the first valve to continuously adjust the flow of gas into the first chamber of the SPS over a first period of time; The SPS is a second gate configured to selectively seal and open the first chamber of the SPS from a third chamber of the SPS; a second valve configured to continuously regulate the flow of gas out of the first chamber of the SPS; the controller is communicatively connected to the second gate and the second valve, and further causing the second gate to seal the first chamber of the SPS from the third chamber of the SPS; causing the second valve to receive a first input signal, the first input signal configured to cause the second valve to continuously adjust the flow of gas out of the first chamber of the SPS over a second period of time; The system is configured as follows:

11. 1. A method of moving a substrate from a first compartment of a substrate processing system (SPS) to a second compartment of the SPS, comprising: opening a first gate between the first and third compartments of the SPS; moving the substrate from the first compartment to the third compartment; closing the first gate to isolate the third compartment from the first compartment; controlling a second gate to isolate the third compartment from the second compartment; initiating a flow of gas, the flow of gas being one of (i) the flow of gas into the third compartment, or (ii) the flow of gas out of the third compartment; causing the flow rate of the gas to have a respective RFR of a plurality of target reference flows (RFRs) at each of a plurality of times, the plurality of RFRs being determined based on modeling that minimizes generation of contaminant particles in the third compartment caused by the flow of the gas; and in response to a pressure change in the third compartment from an initial pressure to a final pressure, opening the second gate and moving the substrate from the third compartment to the second compartment.

12. The flow of the gas flows into the third compartment, and the modeling uses a first model that characterizes drag forces acting on contaminant particles adsorbed on a surface of the third compartment, and inputs to the first model include: the viscosity of the gas; and a velocity of the gas near the surface of the third compartment, the velocity of the gas being determined based on the rate of the flow of the gas into the third compartment.

13. The modeling uses a second model that characterizes the affinity of the contaminant particles for the surface of the third compartment, the modeling comprising: determining an instantaneous probability of resuspension of the contaminant particles from the surface of the third compartment using outputs of the first model and the second model; and determining a percentage of the contaminant particles that remain adsorbed to the surface of the third compartment after a target duration for changing the pressure in the third compartment from the initial pressure to the final pressure.

14. 13. The method of claim 12, wherein the plurality of RFRs are further determined based on (i) a target duration for changing the pressure in the third compartment from the initial pressure to the final pressure, and (ii) a target fraction of contaminant particles that remain adsorbed to the surface of the third compartment.

15. the flow of gas exiting the third compartment, the contaminant particles being water particles, and the modeling The method of claim 11 , comprising determining a respective threshold pressure of a plurality of threshold pressures associated with condensation of the water particles at each of the plurality of times.

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