Method and mechanism for adjusting chucking voltage during substrate manufacturing

Abstract

An electronic device manufacturing system includes a substrate holder configured to secure a substrate during processing and a controller operably coupled to the substrate holder. The controller is configured to apply a first voltage to an electrode of the substrate holder. The controller is further configured to determine a first impedance value between the substrate holder and the substrate. The controller is further configured to determine a delta value between the first impedance value and a predetermined second impedance value and determine whether the delta value satisfies a threshold criterion. In response to the delta value not satisfying the threshold criterion, the controller is further configured to apply a second voltage to the substrate, the second voltage being greater than the first voltage.

Description

[Technical Field]

[0001] The present disclosure relates to electrostatic chucks, and more particularly to methods and mechanisms for adjusting chucking voltages during substrate manufacturing. [Background technology]

[0002] In semiconductor processing chambers using high-power plasma processes, certain chamber hardware is at risk of damage if it comes into unintended contact with the plasma. The substrate holder (also called a "chuck") that holds the substrate may have a heater to raise the substrate's temperature as specified by the particular process recipe. This heater or substrate holder also provides an electrical ground for the plasma used in the deposition or etch reactor. For intended process control and to prevent damage to the hardware and / or substrate, the substrate should be centered in the x-y plane (i.e., the center of the wafer is properly aligned with the chuck) and / or there should be proper contact established between the chuck and substrate in the z-direction. In the case of an electrostatic chuck (ESC), an electrostatic holding force may be applied to the substrate to hold it in place. However, the substrate may have some "bow" that prevents proper contact with the chuck and heater. This potentially exposes the heater to the high-power plasma, causing heater / faceplate damage as well as an undesirable coating on the backside of the substrate, which can result in the substrate being discarded entirely. Summary of the Invention

[0003] The following is a simplified summary of the disclosure to provide a basic understanding of some aspects of the disclosure. This summary is not an extensive overview of the disclosure. It is not intended to identify key or critical elements of the disclosure, nor to delineate the scope or claims of particular implementations of the disclosure. Its sole purpose is to present some concepts of the disclosure in a simplified form as a prelude to the more detailed description that is presented later.

[0004] In an aspect of the present disclosure, an electronic device manufacturing system includes a substrate holder configured to secure a substrate during processing and a controller operably coupled to the substrate holder. The controller is configured to apply a first voltage to an electrode of the substrate holder. The controller is further configured to determine a first impedance value between the substrate holder and the substrate. The controller is further configured to determine a delta value between the first impedance value and a predetermined second impedance value and determine whether the delta value satisfies a threshold criterion. In response to the delta value not satisfying the threshold criterion, the controller is further configured to apply a second voltage to the substrate, the second voltage being greater than the first voltage.

[0005] Further aspects of the present disclosure include methods according to any aspect or embodiment described herein.

[0006] A further aspect of the present disclosure includes a non-transitory computer-readable storage medium comprising instructions that, when executed by a processing device operably coupled to a memory, perform operations according to any aspect or embodiment described herein.

[0007] The present disclosure is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic top view of an exemplary manufacturing system, according to some embodiments. [Figure 2] 1 is a cross-sectional schematic side view of an example process chamber of an example manufacturing system, according to some embodiments. [Figure 3] 1 is a flowchart of a method for performing a chucking sequence on a substrate, according to some embodiments. [Figure 4]1 is a flowchart of a method for performing a dechucking sequence on a substrate, according to some embodiments. [Figure 5] 1 is a flowchart of a method for determining a dechucking profile during a manufacturing process for a substrate, according to some embodiments. [Figure 6] FIG. 1 is a block diagram illustrating a computer system according to some embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0009] Described herein are techniques directed to methods and mechanisms for adjusting chucking voltages during substrate fabrication. An electronic device manufacturing system can be configured to perform one or more manufacturing processes (e.g., a deposition process, an etch process, a polishing process, etc.) on a substrate in one or more process chambers. For example, during a deposition process (e.g., a deposition (CVD) process, an atomic layer deposition (ALD) process, etc.), a film can be deposited on the surface of the substrate. The manufacturing system can use one or more robots to position the substrate on a substrate holder (e.g., a “chuck”) inside the process chamber. The substrate holder can have a heater to raise the temperature of the substrate as specified by a particular process recipe that defines a specific set of operations to be performed on the substrate during the process and can include one or more settings associated with each operation. For example, a deposition process recipe can include a temperature setting for the process chamber, a pressure setting for the process chamber, flow rate settings for precursors for materials included in the film deposited on the substrate surface, etc. Some substrate holders, such as electrostatic chucks (ESCs), can include a platen with an electrode biased with a DC voltage to establish an electrostatic holding force to hold the substrate in place relative to the substrate holder.

[0010] In some cases, layers formed by the deposition process or previous deposition processes can cause the substrate to undergo "bow" (deviation of the center point of the substrate's median surface from the reference plane) that prevents proper contact with the substrate holder and heater. For example, layers formed by a deposition process can exert a force on the edge of the substrate that is greater than the electrostatic force used to hold the substrate in place, causing the edge of the substrate to lift or warp. This exposes the surface of the chuck to high-power plasma, which can not only damage the chuck but also result in an undesirable coating on the backside of the substrate.

[0011] In other cases, when the application of the chucking voltage is discontinued, the residual electrostatic force may take some time to dissipate. This dissipation time may vary based on different factors, such as the strength of the chucking voltage, the number and / or thickness of the deposited layers, etc. Removing the substrate via the robot before the electrostatic force dissipates may cause excessive force to be applied to the substrate, resulting in damage to the substrate, damage to the chuck, etc.

[0012] Aspects and implementations of the present disclosure address these and other shortcomings of existing technologies by adjusting the chucking voltage before, during, and / or after substrate fabrication. Such substrate fabrication can include deposition processes, etch processes, etc. In one embodiment, when a substrate is positioned on a substrate holder, the substrate holder can apply an initial chucking voltage (e.g., 400 volts (V)) to the substrate. The initial chucking voltage can be set during calibration of the fabrication system and can be based on a minimum or average chucking voltage sufficient to chuck a substrate (e.g., a flat substrate or a substrate with an average or minimal amount of curvature). The fabrication system can then measure an impedance value between the substrate holder and the substrate. For example, the fabrication system can take a set of impedance readings using a set of electrical sensors coupled to the substrate holder and determine an average impedance value. The fabrication system can compare this current impedance value to the expected impedance value to determine a delta value (i.e., the difference between the current impedance value and the expected impedance value, optionally expressed as |current impedance value−expected impedance value|). The expected impedance value may be an impedance value that indicates that the chucked substrate is not undergoing bowing (or a minimum acceptable bowing). The manufacturing system may determine whether the delta value meets the chucking threshold criteria (e.g., whether the delta value is below an acceptable limit). In response to the delta value being greater than the acceptable limit, the manufacturing system may increase the chucking voltage by an incremental value (e.g., 10 V). The manufacturing system may then determine a new impedance value, determine a new delta value, and determine whether the new delta value meets the chucking threshold criteria. The manufacturing system may perform this loop until the delta value meets the chucking threshold criteria.

[0013] In one embodiment, when the delta value is less than an acceptable threshold (indicating that the substrate is chucked without bowing), the process chamber begins the fabrication process. During the fabrication process, the fabrication system can take periodic impedance readings, and in response to determining that bowing has occurred (e.g., the delta value becomes greater than the acceptable threshold), the fabrication system can increase the chucking voltage to remove the bow.

[0014] Once the manufacturing process is complete, the manufacturing system can perform a dechucking operation to dechuck the substrate. In particular, the manufacturing system can incrementally decrease the chucking voltage while measuring the impedance between the substrate and the substrate holder to determine a delta value. Once the delta value is greater than the dechuck threshold (indicating that the electrostatic force has dissipated or is not strong enough to cause damage to the substrate during removal), the manufacturing system can remove the substrate from the substrate holder via the transfer chamber robot.

[0015] Aspects of the present disclosure provide the technical advantage of significantly reducing the time taken to chuck and dechuck a substrate. Aspects of the present disclosure provide the technical advantage of preventing substrate bowing during the manufacturing process, thereby preventing damage to the heater and / or faceplate of the substrate holder and preventing undesired coatings on the backside of the substrate. Aspects of the present disclosure provide the technical advantage of preventing damage to the substrate or heater due to removal of the chucked substrate by residual electrostatic forces. This allows the present disclosure, in embodiments, to prevent damaged or defective products and unscheduled user time or downtime for repairs.

[0016] FIG. 1 is a schematic top view of an exemplary manufacturing system 100 according to an embodiment of the present disclosure. The manufacturing system 100 can perform one or more processes to create a product, such as an electronic device, according to a recipe or run over a period of time. Examples of substrate processes include a deposition process for depositing one or more layers of a film on the surface of a substrate, an etch process for forming a pattern on the surface of a substrate, etc. The substrate 102 can be any suitably rigid, planar article of fixed dimensions suitable for fabricating electronic devices or circuit components thereon, such as, for example, a silicon-containing disk or wafer, a patterned wafer, a glass plate, etc. The manufacturing equipment 100 can perform each process according to a process recipe. The process recipe defines a specific set of operations to be performed on the substrate 102 during the process and can include one or more settings associated with each operation. For example, a deposition process recipe can include temperature settings for a process chamber, pressure settings for the process chamber, flow rate settings for precursors for materials included in a film deposited on the substrate surface, etc.

[0017] The manufacturing system 100 may include a process tool 104 and a factory interface 106 coupled to the process tool 104. The process tool 104 may include a housing 108 having a transfer chamber 110 therein. The transfer chamber 110 may include one or more process chambers (also called processing chambers) 114, 116, 118 arranged around and coupled thereto. The process chambers 114, 116, 118 may be coupled to the transfer chamber 110 through respective ports, such as slit valves. The transfer chamber 110 may also include a transfer chamber robot 112 configured to transfer the substrate 102 between the process chambers 114, 116, 118, the load lock 120, etc. The transfer chamber robot 112 may include one or more arms, where each arm includes one or more end effectors at the end of each arm. The end effectors may be configured to handle specific objects, such as wafers, sensor disks, sensor tools, etc.

[0018] The process chambers 114, 116, 118 may be adapted to perform any number of processes on the substrate 102. The same or different substrate processes may be performed in each process chamber 114, 116, 118. Substrate processes may include atomic layer deposition (ALD), physical vapor deposition (PVD), chemical vapor deposition (CVD), etching, annealing, curing, pre-cleaning, metal or metal oxide removal, etc. Other processes may be performed on the substrate therein. The process chambers 114, 116, 118 may each include one or more sensors configured to capture data about the substrate 102 before, after, or during substrate processing. For example, the one or more sensors may be configured to capture spectral and / or non-spectral data about a portion of the substrate 102 during substrate processing. In other or similar embodiments, the one or more sensors may be configured to capture data related to the environment within the process chambers 114, 116, 118 before, after, or during substrate processing. For example, one or more sensors may be configured to capture data related to the temperature, pressure, gas concentrations, etc. of the environment within the process chambers 114, 116, 118 during substrate processing.

[0019] A load lock 120 may also be coupled to the housing 108 and the transfer chamber 110. The load lock 120 may be configured to interface with and be coupled to the transfer chamber 110 on one side and the factory interface 106 on the other. The load lock 120, in some embodiments, may have an environmentally controlled atmosphere that may be changed from a vacuum environment (where substrates may be transferred to and from the transfer chamber 110) to at or near an atmospheric pressure inert gas environment (where substrates may be transferred to and from the factory interface 106). The factory interface 106 may be any suitable enclosure, such as, for example, a front-end equipment module (EFEM). The factory interface 106 may be configured to receive substrates 102 from substrate carriers 122 (e.g., front-opening unified pods (FOUPs)) docked at various load ports 124 of the factory interface 106. A factory interface robot 126 (shown in dotted lines) may be configured to transfer substrates 102 between carriers (also called containers) 122 and load locks 120. Carriers 122 may be substrate storage carriers or replacement part storage carriers.

[0020] Manufacturing system 100 may also be connected to client devices (not shown) configured to provide information about manufacturing system 100 to a user (e.g., an operator). Client devices may include computing devices such as personal computers (PCs), laptops, mobile phones, smartphones, tablet computers, netbook computers, network-connected televisions ("smart TVs"), network-connected media players (e.g., Blu-ray players), set-top boxes, over-the-top (OTT) streaming devices, operator boxes, etc. In some embodiments, client devices may provide information to a user of manufacturing system 100 via one or more graphical user interfaces (GUIs). For example, a client device may provide information about chucking or dechucking status via a GUI according to embodiments described herein.

[0021] The manufacturing system 100 can also include a system controller 128. The system controller 128 can be and / or include a computing device such as a personal computer, a server computer, a programmable logic controller (PLC), a microcontroller, etc. The system controller 128 can include one or more processing devices, which can be general-purpose processing devices such as a microprocessor, a central processing unit, etc. More specifically, the processing device can be 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 a processor implementing a combination of instruction sets. The processing device can 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, etc. The system controller 128 can include a data storage device (e.g., one or more disk drives and / or solid-state drives), a main memory, a static memory, a network interface, and / or other components. The system controller 128 may execute instructions to implement any one or more of the methodologies and / or embodiments described herein. In some embodiments, the system controller 128 may execute instructions to perform one or more operations in the manufacturing system 100 according to a process recipe. The instructions may be stored in a computer-readable storage medium, which may include a main memory, a static memory, a secondary storage, and / or a processing device (during execution of the instructions).

[0022] The system controller 128 may receive data from sensors contained on or within various portions of the manufacturing system 100 (e.g., processing chambers 114, 116, 118, transfer chamber 110, load lock 120, etc.). In some embodiments, the data received by the system controller 128 may include spectral and / or non-spectral data about a portion of the substrate 102. In other or similar embodiments, the data received by the system controller 128 may include data related to processing the substrate 102 in the processing chambers 114, 116, 118, as previously described. For purposes of this specification, the system controller 128 will be described as receiving data from sensors contained within the process chambers 114, 116, 118. However, the system controller 128 may receive data from any portion of the manufacturing system 100 and use the data received therefrom, according to embodiments described herein. In an illustrative example, the system controller 128 may receive data from one or more sensors for the process chambers 114, 116, 118 before, after, or during substrate processing in the process chambers 114, 116, 118. The data received from the sensors in various portions of the manufacturing system 100 may be stored in a data store 150. The data store 150 may be included as a component within the system controller 128 or may be a separate component from the system controller 128.

[0023] Data store 150 may be memory (e.g., random access memory), a drive (e.g., a hard drive, a flash drive), a database system, or another type of component or device capable of storing data. Data store 150 may include multiple storage components (e.g., multiple drives or multiple databases) that may span multiple computing devices (e.g., multiple server computers). Data store 150 may store data related to processing substrates on manufacturing equipment 100. For example, data store 150 may store data (referred to as process data) collected by sensors on the manufacturing equipment before, during, or after a substrate process. Process data may refer to historical process data (e.g., process data generated for a previous substrate processed on the manufacturing system) and / or current process data (e.g., process data generated for a current substrate being processed on the manufacturing system). Data store 150 may also store spectral or non-spectral data related to a portion of a substrate processed on manufacturing equipment 100. Spectral data may include historical spectral data and / or current spectral data.

[0024] The data store 150 may also store context data associated with one or more substrates processed in the manufacturing system. The context data may include a recipe name, a recipe step number, a preventative maintenance indicator, an operator, etc. The context data may refer to historical context data (e.g., context data associated with a previous process performed on a previous substrate) and / or current process data (e.g., context data associated with a current or future process to be performed on a previous substrate). The context data may further include and identify sensors associated with particular subsystems of a process chamber.

[0025] The data store 150 can also store task data. The task data can include one or more sets of operations to be performed on a substrate during a deposition process and can include one or more settings associated with each operation. For example, task data for a deposition process can include temperature settings for a process chamber, pressure settings for the process chamber, flow rate settings for precursors for a material of a film to be deposited on the substrate, etc. In another example, the task data can include control pressures at defined pressure points for flow values. Task data can refer to historical task data (e.g., task data associated with a previous process performed on a previous substrate) and / or current task data (e.g., task data associated with a current or future process to be performed on a substrate).

[0026] In some embodiments, the data store 150 can store chucking profiles. The chucking profiles can include chucking voltages for different steps of a process recipe. For example, for a particular deposition recipe, the chucking profile can include a first chucking voltage (450 V) for the first 20 deposition layers or a first layer thickness range, a second chucking voltage (470 V) for the next 20 deposition layers or a second layer thickness range, a third chucking voltage (e.g., 500 V) for the next 30 layers or a third layer thickness range, etc. Each chucking profile can be generated using user input or during the manufacturing process. For example, during a deposition process using a particular recipe, the manufacturing system can perform a chucking sequence (discussed in FIG. 3 ) and determine which steps of the process recipe should receive an increase in chucking voltage. Chucking profiles can be generated based on these increases, and during subsequent deposition processes using the particular deposition recipe, the manufacturing system can increase the chucking voltage during particular process steps as indicated by the chucking profile.

[0027] In some embodiments, the data store 150 can store dechucking profiles. The dechucking profile can include a chucking voltage for safe removal of a substrate from a substrate holder. For example, for a particular deposition recipe, the dechucking profile can include a chucking voltage (hereinafter, a “removal chucking voltage”) that reflects an electrostatic force that is not strong enough to cause damage to the substrate during removal. Each dechucking profile can be generated using user input or during a manufacturing process. For example, during a deposition process using a particular recipe, the manufacturing system can perform a dechucking sequence (discussed in FIG. 4 ) and determine a removal chucking voltage (a voltage low enough to allow safe substrate removal). During a subsequent deposition process using a particular deposition recipe, the manufacturing system can reduce the chucking voltage to the removal chucking voltage as indicated by the dechucking profile.

[0028] In some embodiments, data store 150 may be configured to store data that is not accessible to users of the manufacturing system. For example, process data, spectral data, contextual data, etc. acquired for substrates being processed in the manufacturing system are not accessible to users (e.g., operators) of the manufacturing system. In some embodiments, all data stored in data store 150 may be inaccessible by users of the manufacturing system. In other or similar embodiments, some portions of the data stored in data store 150 may be inaccessible by users, while other portions of the data stored in data store 150 may be accessible by users. In some embodiments, one or more portions of the data stored in data store 150 may be encrypted using an encryption mechanism unknown to the users (e.g., the data is encrypted using a private encryption key). In other or similar embodiments, data store 150 may include multiple data stores, where data that is inaccessible to users is stored in one or more first data stores and data that is accessible to users is stored in one or more second data stores.

[0029] FIG. 2 is a cross-sectional schematic side view of a process chamber 200 according to an embodiment of the present disclosure. In some embodiments, the process chamber 200 can correspond to the process chambers 114, 116, and 118 described with respect to FIG. 1 . The process chamber 200 can be used for a process in which a corrosive plasma environment is provided. For example, the process chamber 200 can be a chamber for a plasma etcher or a plasma etch reactor. In another example, the process chamber can be a chamber for a deposition process, as previously described. In one embodiment, the process chamber 200 includes a chamber body 201 and a showerhead 230 enclosing an interior volume 206. The showerhead 230 can include a showerhead base and a showerhead gas distribution plate. Alternatively, the showerhead 230 can be replaced by a lid and a nozzle in some embodiments, or by multiple pie-shaped showerhead sections and plasma generation units in other embodiments. The chamber body 201 can be fabricated from other suitable materials, such as aluminum, stainless steel, or titanium (Ti). The chamber body 201 generally includes a sidewall 208 and a bottom 210. An exhaust port 226 may be defined in the chamber body 201 and may couple the interior volume 206 to a pumping system 228. The pumping system 228 may include one or more pumps and a throttle valve utilized to evacuate and adjust the pressure of the interior volume 206 of the process chamber 200.

[0030] The showerhead 230 may be supported on the sidewall 208 of the chamber body 201. The showerhead 220 (or lid) may be opened to allow access to the interior volume 206 of the process chamber 200 and may provide a seal to the process chamber 200 when closed. A gas panel 258 may be coupled to the process chamber 200 to provide process and / or cleaning gases to the interior volume 206 through the showerhead 230 or the lid and nozzles (e.g., through apertures in the showerhead or lid and nozzles). For example, the gas panel 258 may provide precursors for the material of the film 251 to be deposited on the surface of the substrate 202. In some embodiments, the precursors may include silicon-based precursors or boron-based precursors. The showerhead 230 may include a gas distribution plate (GDP) and may have multiple gas supply holes 232 (also called channels) throughout the GDP.

[0031] A substrate support assembly 248 is disposed in the interior volume 206 of the process chamber 200 below the showerhead 230. The substrate support assembly 248 holds the substrate 202 during processing (e.g., during a deposition process) using, for example, a substrate holder 250.

[0032] The substrate holder 250 may comprise an electrostatic chuck (ESC), although the scope of the present disclosure is not limited to an ESC. The ESC may be or include a platen with an electrode 255 that may be biased with a voltage (e.g., a direct current (“DC”) voltage) to establish an electrostatic holding force to hold the substrate 202 in place relative to the substrate holder 250.

[0033] A power supply 272 (e.g., a DC power supply) may be coupled to the electrode 255 of the substrate holder 150 to create an electrostatic force that holds the substrate 202 downward. The power supply 272, in embodiments, may be a monopolar power supply or a bipolar power supply. A controller 275 may be coupled to the electrode 255 (or to the power supply 272 coupled to the electrode 255). In embodiments, the controller 275 corresponds to the system controller 128 of FIG. 1. The controller 275 may adjust the power provided by the power supply 272 that powers the electrode 255 to adjust the electrostatic chucking force.

[0034] In an embodiment, the substrate holder 250 includes one or more heating elements 260 that can heat one or more zones of the substrate holder 250 and of the substrate 202. A power supply 273 can be connected to the heating elements 273 and can provide power to the heating elements 260 to heat the substrate 202 to a target temperature before, during, and / or after processing. A controller 275 can be connected to the power supplies 273 to control them. Different layers on the substrate 202 can have different thermal expansion coefficients. As the substrate 202 heats up, these different thermal expansion coefficients can cause the substrate 202 to curve.

[0035] Ideally, there should be no gap between the substrate 202 and the surface of the substrate holder 250. However, improper chucking and / or excessive substrate curvature can result in an undesirable finite gap between the substrate 202 and the surface of the substrate holder 250. Because of this gap, arcing can occur between the substrate 202 and the substrate holder 250 when the high-power radio frequency plasma is on, and the arcing can damage exposed portions of the substrate holder 250 (including the heater and faceplate) and the substrate 202 itself. Also, when the plasma reaches the gap, an undesirable coating can be deposited on the backside of the substrate 202.

[0036] The substrate holder 250 may include one or more electrical sensors 270 to measure one or more electrical properties (e.g., impedance, magnetic variations in a power supply conductor, current, voltage, resistance, etc.) between the substrate 202 and the substrate holder 250. The electrical sensors 270 may also measure one or more of the following: current, alternating current (AC) magnitude, phase, waveform (e.g., alternating current (AC) waveform, pulse waveform), direct current (DC), non-sinusoidal AC waveform, voltage, etc. In some embodiments, the electrical sensors 270 may be embedded in the substrate holder (e.g., non-contact sensors). In some embodiments, the electrical sensors 270 may be positioned on and exposed to the surface of the substrate holder. In some embodiments, the electrical sensors 270 may be one or more of a piezoelectric sensor, a charge output sensor, a charge-coupled device (CCD), a capacitive sensor, a resistive sensor, or any other type of electrical sensor capable of measuring one or more electrical properties.

[0037] The controller 275 may be connected to the electrical sensor 270 and may receive measurements from the electrical sensor 270. The controller 275 may be coupled to a data store 280, which may correspond to the data store 150 in an embodiment. The controller 275 may determine target or threshold measurements from the data store 150 and compare the measured electrical values ​​received from the electrical sensor 270 to the stored values. The stored values ​​may indicate a value achieved when the supported substrate is in sufficient contact with the surface of the substrate holder 250. If the measurements deviate from the stored values ​​by more than a deviation threshold, this may indicate that the substrate is bowed (and thus that a portion of the substrate is not in sufficient contact with the surface of the substrate holder 250). Accordingly, the controller 275 may adjust the power supplied to the electrode 255 in response to determining that the measurements deviate from the target value by more than a threshold difference amount. The increased power or voltage may cause the electrode to pull the substrate flat, ensuring sufficient contact between the substrate and the surface of the substrate holder. Such sufficient contact promotes adequate heat transfer between the substrate holder 250 and the substrate 202 and eliminates gaps between the substrate holder 250 and the substrate 202 that can cause arcing, can cause the exposed backside of the substrate to become coated, etc.

[0038] 3 is a flowchart of a method 300 for performing a chucking sequence on a substrate according to an embodiment of the present disclosure. Method 300 is performed by processing logic, which may include hardware (such as electrical circuitry, dedicated logic circuitry, etc.), software (such as that running on a general-purpose computer system or dedicated machine), firmware, or some combination thereof. In one implementation, method 300 may be performed by one or more components of manufacturing system 100 of FIG. 1 and / or processing chamber 200 of FIG. 2, such as system controller 128 and / or controller 275. In other or similar implementations, one or more operations of method 300 may be performed by one or more other machines not depicted in the figures, such as, for example, a client device.

[0039] In operation 310, processing logic positions a substrate on a substrate holder. For example, processing logic may be configured to instruct a transfer chamber robot (e.g., transfer chamber robot 112) to transfer a substrate (e.g., substrate 102) to a process chamber (e.g., process chambers 114, 116, 118) and position the substrate on a substrate holder.

[0040] In operation 320, processing logic applies an initial chucking voltage to the substrate positioned on the substrate holder. In some embodiments, the initial chucking voltage may be set during calibration of the fabrication system or process chamber. For example, the initial chucking voltage may be determined based on a minimum or average chucking voltage that is sufficient to chuck the substrate without bowing and / or warping. In some embodiments, the initial chucking voltage may be set by user input via a client device. In some embodiments, the initial chucking voltage may be determined using a chucking profile. In some embodiments, prior to positioning the substrate on the substrate holder, the bow of the incoming substrate may be measured, and the power of the DC power supply is adjusted accordingly to adjust the electrostatic chucking force sufficient to maintain contact with the substrate holder having the determined amount of bowing. The bowing may be measured using one or more sensors of the fabrication system 100 (e.g., using a distance measurement sensor to determine the distance from the center of the substrate to one or more edges of the substrate) or via manual calculation by a user. Based on the determined curvature, processing logic may reference a data structure (a format having a set of data values, relationships between them, and / or functions or operations that may be applied to the data values) stored in a data store to determine a corresponding initial chucking voltage. For example, different amounts of curvature may be associated with different initial chucking voltages. The higher the amount of curvature, the higher the initial chucking voltage required to resolve the curvature and pull the substrate flat against the substrate holder. In some embodiments, once the substrate is received, processing logic may wait a predetermined period of time before performing operation 320.

[0041] In operation 330, processing logic determines a current impedance value (or other measurement) between the substrate holder and the substrate. In some embodiments, processing logic may determine the current impedance value (or other measurement) by obtaining one or more measurements using one or more electrical sensors coupled to the substrate holder. For example, processing logic may obtain multiple impedance readings from different electrical sensors coupled to or embedded in the substrate holder and determine an average impedance value from the multiple impedance readings.

[0042] In operation 340, processing logic determines a delta value between the current value (e.g., impedance value) and the expected or target value (e.g., impedance value). In one embodiment, the delta is determined by subtracting the expected value from the current value and / or determining the absolute value of the difference between the two values. The expected value (e.g., impedance value) may be a value that indicates that the chucked substrate is not experiencing any curvature (or is experiencing a minimum acceptable curvature). In some embodiments, the expected value may be obtained from a data structure stored in a data store. The expected value may be determined, for example, based on experimental results performed by one or more users.

[0043] In operation 350, processing logic determines whether the delta value meets a chucking threshold criterion. In some embodiments, the chucking threshold criterion is a predetermined threshold. For example, processing logic may determine whether the delta value is below a predetermined threshold. In response to the delta value meeting the chucking threshold (e.g., being lower than the predetermined threshold, thereby indicating that the substrate has been chucked), processing logic proceeds to operation 370, where processing logic may perform one or more operations of a process recipe. In response to the delta value not meeting the predetermined threshold (e.g., being greater than the predetermined threshold), processing logic proceeds to operation 360.

[0044] In operation 360, processing logic may increase the chucking voltage applied to the substrate. In some embodiments, processing logic may increase the chucking voltage by a predetermined increment. For example, processing logic may increase the chucking voltage by 10 V. In some embodiments, in response to increasing the chucking voltage, processing logic may wait a predetermined time before proceeding to the next operation. This delay may allow electrostatic forces to affect the substrate. Processing logic then proceeds to operation 330 to determine a new value (e.g., a new impedance value) between the substrate holder and the substrate. The new value may then be compared to an expected value to again determine whether the substrate is properly chucked. If the substrate is not properly chucked, the method may return to block 330 again after again increasing the chucking voltage. This process may continue until the substrate is sufficiently chucked.

[0045] Once the substrate is properly chucked (in other words, the substrate curvature is substantially eliminated and / or threshold criteria are met), the method proceeds to operation 370 where the manufacturing process is performed.

[0046] In some embodiments, during the manufacturing process, the manufacturing system may take periodic readings (e.g., periodic impedance readings). After each such reading, the measured value (e.g., impedance value) may be compared to an expected value, and the absolute value of the difference between the two values ​​may be compared to a threshold criterion. The manufacturing process may cause the substrate to bow (or bow more than it was originally bowed), which may cause the substrate to no longer be properly chucked. Thus, in response to determining that bowing is occurring (e.g., the delta value is greater than the chucking threshold), the manufacturing system may increase the chucking voltage until the new delta value meets the threshold criterion. Thus, the operations of blocks 330-370 may be performed periodically or continuously during the manufacturing process in addition to, or instead of, before the manufacturing process begins.

[0047] In some embodiments, processing logic can generate and / or update a chucking profile. For example, the chucking profile can be associated with a particular process recipe used for a substrate to be chucked. Prior to execution of the process recipe, processing logic can update the chucking profile to include the chucking voltage used to chuck the substrate and correlate each chucking voltage increment (or set of chucking voltage increments) with each corresponding process recipe step. Thus, during a subsequent manufacturing process using a particular process recipe, processing logic can use the chucking profile to set an initial chucking voltage and implement the chucking voltage increments during specified steps of the process recipe.

[0048] 4 is a flowchart of a method 400 for performing a dechucking sequence on a substrate according to an embodiment of the present disclosure. Method 400 is performed by processing logic, which may include hardware (such as electrical circuitry, dedicated logic circuitry, etc.), software (such as that running on a general-purpose computer system or dedicated machine), firmware, or some combination thereof. In one implementation, method 400 may be performed by one or more components of manufacturing system 100 of FIG. 1 and / or processing chamber 200 of FIG. 2, such as system controller 128 and / or controller 275. In other or similar implementations, one or more operations of method 400 may be performed by one or more other machines not depicted in the figures, such as, for example, a client device.

[0049] In operation 410, processing logic applies a chucking voltage to the substrate chucked to the substrate holder. In some embodiments, the chucking voltage may be the same as the last chucking voltage applied during the manufacturing process. In some embodiments, the chucking voltage may be the maximum chucking voltage capable of being applied by the substrate holder. In some embodiments, the chucking voltage may be a user-defined voltage, a predetermined voltage, or a voltage obtained from a dechucking profile. In some embodiments, before performing operation 410, processing logic may wait a predetermined period of time after completion of the manufacturing process for the substrate. In some embodiments, processing logic may perform one or more dechucking procedures, such as flushing the process chamber with an inert gas, before performing operation 410.

[0050] In operation 420, processing logic determines a current impedance value (or other measurement) between the substrate holder and the substrate. In some embodiments, processing logic may determine the current impedance value (or other measurement) by obtaining one or more measurements using one or more electrical sensors coupled to the substrate holder. For example, processing logic may obtain multiple impedance readings from different electrical sensors coupled to or embedded in the substrate holder and determine an average impedance value from the multiple impedance readings.

[0051] In operation 430, processing logic determines a delta value between the current value (e.g., impedance value) and the expected or target value (e.g., impedance value). In one embodiment, the delta is determined by subtracting the expected value from the current value and / or determining the absolute value of the difference between the two values. The expected value (e.g., impedance value) may be a value that indicates that the electrostatic force has dissipated or is not strong enough to cause damage to the substrate during removal of the substrate. In some embodiments, the expected value may be obtained from a data structure stored in a data store. The expected value may be determined, for example, based on experimental results performed by one or more users.

[0052] In operation 440, processing logic determines whether the delta value meets the dechuck threshold criterion. In some embodiments, the dechuck threshold criterion is a threshold value. For example, processing logic may determine whether the delta value is greater than a predetermined threshold. In response to the delta value meeting the dechuck threshold (e.g., greater than the predetermined threshold, thereby indicating that the substrate has been dechucked), processing logic proceeds to operation 460, where processing logic may indicate to the manufacturing system that the substrate has been dechucked. In response to the delta value not meeting the predetermined threshold (e.g., less than the predetermined threshold), processing logic proceeds to operation 450. In some embodiments, the dechuck threshold criterion is similar to or the same as the chucking threshold criterion. In other embodiments, the dechuck threshold criterion is a value independent of the chucking threshold criterion.

[0053] In operation 450, processing logic decreases the chucking voltage applied to the substrate. In some embodiments, processing logic may decrease the chucking voltage by a predetermined increment. For example, processing logic may decrease the chucking voltage by 10 V. In some embodiments, in response to decreasing the chucking voltage, processing logic may wait a predetermined time before proceeding to the next operation. This delay may allow electrostatic forces to dissipate from the substrate and / or substrate holder. Processing logic then proceeds to operation 420 and determines a new value (e.g., a new impedance value) between the substrate holder and the substrate. The new value may then be compared to an expected value to again determine whether the substrate has been dechucked. If the substrate has not been dechucked, the method may return to block 420 after again decreasing the chucking voltage. This process may continue until the substrate is dechucked.

[0054] Once the substrate is properly dechucked, the method proceeds to operation 460, where a transfer chamber robot (eg, transfer chamber robot 112) can remove the substrate from the substrate holder.

[0055] In some embodiments, processing logic can generate and / or update the dechucking profile. For example, processing logic can update the dechucking profile to include a dechucking voltage at which the substrate will be dechucked. Thus, during a subsequent manufacturing process, processing logic can use the chucking profile to set an initial chucking voltage during a dechucking operation.

[0056] 5 is a flowchart of a method 500 for determining a dechucking profile during a manufacturing process for a substrate according to an embodiment of the present disclosure. Method 500 is implemented by processing logic, which may include hardware (such as electrical circuitry, dedicated logic circuitry, etc.), software (such as that running on a general-purpose computer system or dedicated machine), firmware, or some combination thereof. In one implementation, method 500 may be implemented by one or more components of manufacturing system 100 of FIG. 1 and / or processing chamber 200 of FIG. 2, such as system controller 128 and / or controller 275. In other or similar implementations, one or more operations of method 500 may be implemented by one or more other machines not depicted in the figures, such as, for example, a client device. Method 500 may be initiated in response to user input or automatically (e.g., following a step in a recipe, in response to completion of a manufacturing process, etc.).

[0057] The method 500 may be performed while a manufacturing process is being performed on a substrate.

[0058] At operation 510, processing logic determines whether the manufacturing system includes a dechucking profile for the executed process recipe. For example, processing logic may query a data store for any corresponding dechucking profiles. In response to determining that the manufacturing system includes a corresponding dechucking profile, processing logic proceeds to operation 570. In response to determining that the manufacturing system does not include a corresponding dechucking profile, processing logic proceeds to operation 515.

[0059] In operation 515, processing logic applies a maximum chucking voltage to the substrate chucked to the substrate holder. The maximum chucking voltage may be the maximum voltage value that the substrate holder can apply to the coupled electrode.

[0060] In operation 520, processing logic determines a current impedance value (or other measurement) between the substrate holder and the substrate. In some embodiments, processing logic may determine the current impedance value (or other measurement) by obtaining one or more measurements using one or more electrical sensors coupled to the substrate holder. For example, processing logic may obtain multiple impedance readings from different electrical sensors coupled to or embedded in the substrate holder and determine an average impedance value from the multiple impedance readings. In some embodiments, processing logic may determine the current impedance value by obtaining one or more measurements over a predetermined period of time (e.g., a monitoring time).

[0061] In operation 525, processing logic decreases the chucking voltage applied to the substrate. In some embodiments, processing logic may decrease the chucking voltage by a predetermined increment (e.g., 10 V). In some embodiments, in response to increasing the chucking voltage, processing logic may wait a predetermined time to allow electrostatic forces to dissipate from the substrate and / or substrate holder before proceeding to the next operation.

[0062] In operation 530, processing logic determines whether the chucking voltage has reached a minimum chucking voltage. The minimum chucking voltage may be the minimum voltage required to chuck the substrate to the substrate holder. In response to determining that the chucking voltage has reached the minimum chucking voltage, processing logic proceeds to operation 545. In response to determining that the chucking voltage has not reached the minimum chucking voltage, processing logic proceeds to operation 540.

[0063] In operation 540, processing logic determines whether the impedance change is greater than a threshold value. In particular, processing logic may first determine a delta value between the current impedance value and an expected or target impedance value. In one embodiment, the delta is determined by subtracting the expected value from the current value and / or determining the absolute value of the difference between the two values. The expected value may be a value that indicates that the chucked substrate is not experiencing any curvature (or is experiencing a minimum acceptable curvature). In some embodiments, the expected value may be obtained from a data structure stored in a data store. The expected value may be determined, for example, based on experimental results performed by one or more users. Processing logic may then determine whether the delta value meets a chucking threshold criterion. In some embodiments, the chucking threshold criterion is a predetermined threshold. For example, processing logic may determine whether the delta value is below a predetermined threshold. In response to the delta value meeting the chucking threshold (e.g., being lower than a predetermined threshold, thereby indicating that the substrate is chucked), processing logic proceeds to operation 525 and reduces the chucking voltage applied to the substrate. In response to the delta value not meeting a predetermined threshold (e.g., being greater than a predetermined threshold, thereby indicating that the substrate is dechucked), processing logic proceeds to operation 545.

[0064] In operation 545, processing logic increases the chucking voltage to chuck the substrate. In some embodiments, processing logic may increase the chucking voltage by the predetermined increment used in operation 525 (e.g., 10 V) or by any other predetermined increment.

[0065] In operation 550, processing logic may store in a metadata table the voltage value that reflects the delta value not meeting a predetermined threshold. In particular, processing logic may store the voltage value at which the substrate was not chucked (e.g., the voltage value prior to operation 545). In some embodiments, processing logic may generate a dechucking profile for the current process recipe based on this voltage value.

[0066] In operation 555, processing logic initiates an auto-compensator chucking sequence to automatically keep the substrate chucked on the substrate holder. For example, processing logic may initiate method 300.

[0067] Returning to operation 510, in response to determining that the manufacturing system includes a corresponding dechucking profile, processing logic proceeds to operation 570. At operation 570, processing logic applies a dechucking voltage obtained from the dechucking profile.

[0068] In operation 575, processing logic determines whether the auto-compensator chucking sequence is enabled. In response to determining that the auto-compensator chucking sequence is enabled, processing logic proceeds to operation 580 and initiates the auto-compensator chucking sequence to automatically keep the substrate chucked on the substrate holder. In response to determining that the auto-compensator chucking sequence is not enabled, processing logic proceeds to operation 585 and maintains the current chucking voltage.

[0069] 6 is a block diagram illustrating a computer system 600, according to some embodiments. In some embodiments, computer system 600 may be connected to other computer systems (e.g., via a network, such as a local area network (LAN), an intranet, an extranet, or the Internet). Computer system 600 may operate in the capacity of a server computer or a client computer in a client-server environment, or as a peer computer in a peer-to-peer or distributed network environment. Computer system 600 may be provided by a personal computer (PC), a tablet PC, a set-top box (STB), a personal digital assistant (PDA), a cellular phone, a web appliance, a server, a network router, switch, or bridge, or any device capable of executing a set of instructions (sequential or otherwise) that specify actions to be taken by that device. Furthermore, the term "computer" is intended to include any collection of computers that, individually or together, execute a set (or sets) of instructions to perform any one or more of the methodologies described herein.

[0070] In a further aspect, the computer system 600 may include a processing device 602, a volatile memory 604 (e.g., random access memory (RAM)), a non-volatile memory 606 (e.g., read-only memory (ROM) or electrically erasable programmable ROM (EEPROM)), and a data storage device 616, which may communicate with each other via a bus 608.

[0071] The processing device 602 may be provided by one or more processors, such as a general-purpose processor (e.g., a complex instruction set computing (CISC) microprocessor, a reduced instruction set computing (RISC) microprocessor, a very long instruction word (VLIW) microprocessor, a microprocessor implementing other types of instruction sets, or a microprocessor implementing a combination of types of instruction sets), or a special-purpose processor (e.g., an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a digital signal processor (DSP), or a network processor).

[0072] Computer system 600 may further include a network interface device 622 (e.g., coupled to a network 674). Computer system 600 may also include a video display device 610 (e.g., an LCD), an alphanumeric input device 612 (e.g., a keyboard), a cursor control device 614 (e.g., a mouse), and a signal generating device 620.

[0073] 1 (e.g., a chucking module (not shown) of system controller 128, a dechucking module (not shown) of system controller 128, etc.) and for implementing the methods described herein. In some embodiments, the chucking module may perform the operations of method 300. In some embodiments, the dechucking module may perform the operations of method 400.

[0074] The instructions 626 may also reside, completely or partially, within the volatile memory 604 and / or within the processing device 602 during execution thereof by the computer system 600; thus, the volatile memory 604 and the processing device 602 may also constitute machine-readable storage media.

[0075] Although computer-readable storage medium 624 is shown as a single medium in the illustrative example, the term "computer-readable storage medium" is intended 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 executable instructions. The term "computer-readable storage medium" is also intended to include any tangible medium capable of storing or encoding a set of instructions for execution by a computer, causing the computer to perform any one or more of the methodologies described herein. The term "computer-readable storage medium" is intended to include, but is not limited to, solid-state memory, optical media, and magnetic media.

[0076] The methods, components, and features described herein may be implemented by discrete hardware components or may be integrated into the functionality of other hardware components, such as an ASIC, FPGA, DSP, or similar device. In addition, the methods, components, and features may be implemented by firmware modules or functional circuits within a hardware device. Furthermore, the methods, components, and features may be implemented in any combination of hardware devices and computer program components, or implemented in a computer program.

[0077] Unless otherwise specified, terms such as "receiving," "performing," "providing," "obtaining," "causing," "accessing," "determining," "adding," "using," "training," and the like refer to actions and processes performed or implemented by a computer system that manipulate data represented as physical (electronic) quantities in computer system registers and memory and transform that data into other data similarly represented as physical quantities in the computer system memory or registers, or other such information storage, transmission, or display device. Also, as used herein, terms such as "first," "second," "third," "fourth," and the like are meant as labels to distinguish between different elements and may not have any ordering meaning due to their numerical designation.

[0078] The examples described herein also relate to apparatus for performing the methods described herein. The apparatus may be specially constructed to perform the methods described herein, or the apparatus may comprise a general-purpose computer system that is selectively programmed by a computer program stored on the computer system. Such a computer program may be stored on a computer-readable tangible storage medium.

[0079] The methods and illustrative examples described herein are not inherently related to any particular computer or other apparatus. Various general-purpose systems may be used in accordance with the teachings described herein, or it may prove convenient to construct more specialized apparatus to perform the methods described herein and / or each of their individual functions, routines, subroutines, or operations. Example structures for a variety of these systems are set forth in the description above.

[0080] The above description is illustrative, and not limiting. While the present disclosure has been described with reference to particular illustrative examples and implementations, it will be recognized that the disclosure is not limited to the described examples and implementations. The scope of the present disclosure should be determined with reference to the following claims, along with the full scope of equivalents to which such claims are entitled.

Claims

1. applying a first voltage to an electrode of the substrate holder; determining a first impedance value between the substrate holder and the substrate; determining a delta value between the first impedance value and a predetermined second impedance value; determining whether the delta value meets a threshold criterion; applying a second voltage to the substrate in response to the delta value not meeting the threshold criterion, the second voltage being greater than the first voltage; A method comprising:

2. The method of claim 1 , wherein the first voltage reflects an electrostatic chucking force sufficient to maintain the substrate in contact with the substrate holder.

3. The method of claim 1 , wherein the first impedance value comprises an average impedance determined from multiple measurements using one or more electrical sensors coupled to the substrate holder.

4. The method of claim 1 , wherein the second impedance value comprises an impedance value indicative of the chucked substrate not experiencing any curvature.

5. The method of claim 1 , wherein the second voltage comprises the sum of the first voltage and an incremental voltage value.

6. performing one or more actions of a process recipe in response to the delta value satisfying the threshold criterion. The method of claim 1 further comprising:

7. determining a third impedance value between the substrate holder and the substrate; determining a new delta value between the third impedance value and a predetermined fourth impedance value; determining whether the delta value meets a dechucking threshold criterion; applying a fourth voltage to the substrate in response to the new delta value not meeting the dechucking threshold criterion, the fourth voltage being less than the third voltage; The method of claim 1 further comprising:

8. a substrate holder configured to secure the substrate during processing; a controller operably coupled to the substrate holder, the controller comprising: applying a first voltage to an electrode of the substrate holder; determining a first impedance value between the substrate holder and the substrate; determining a delta value between the first impedance value and a predetermined second impedance value; determining whether the delta value meets a threshold criterion; applying a second voltage to the substrate in response to the delta value not meeting the threshold criterion, the second voltage being greater than the first voltage; The controller and An electronic device manufacturing system comprising:

9. The electronic device manufacturing system of claim 8 , wherein the first voltage reflects an electrostatic chucking force sufficient to maintain the substrate in contact with the substrate holder.

10. The electronic device manufacturing system of claim 8 , wherein the first impedance value comprises an average impedance determined from a plurality of measurements using one or more electrical sensors coupled to the substrate holder.

11. 9. The electronic device manufacturing system of claim 8, wherein the second impedance value comprises an impedance value indicative of the chucked substrate not experiencing any bending.

12. The electronic device manufacturing system of claim 8 , wherein the second voltage comprises the sum of the first voltage and an incremental voltage value.

13. The electronic device manufacturing system of claim 8 , further comprising: performing one or more actions of a process recipe in response to the delta value satisfying the threshold criterion.

14. The processing device determining a third impedance value between the substrate holder and the substrate; determining a new delta value between the third impedance value and a predetermined fourth impedance value; determining whether the delta value meets a dechucking threshold criterion; applying a fourth voltage to the substrate in response to the new delta value not meeting the dechucking threshold criterion, the fourth voltage being less than the third voltage; The electronic device manufacturing system of claim 8 further comprising:

15. When executed by a processing device operably coupled to the memory, applying a first voltage to an electrode of the substrate holder; determining a first impedance value between the substrate holder and the substrate; determining a delta value between the first impedance value and a predetermined second impedance value; determining whether the delta value meets a threshold criterion; applying a second voltage to the substrate in response to the delta value not meeting the threshold criterion, the second voltage being greater than the first voltage; A non-transitory computer-readable storage medium containing instructions for performing operations including:

16. 16. The non-transitory computer-readable storage medium of claim 15, wherein the first voltage reflects an electrostatic chucking force sufficient to maintain the substrate in contact with the substrate holder.

17. 16. The non-transitory computer-readable storage medium of claim 15, wherein the first impedance value comprises an average impedance determined from a plurality of measurements using one or more electrical sensors coupled to the substrate holder.

18. 16. The non-transitory computer-readable storage medium of claim 15, wherein the second impedance value comprises an impedance value indicative of the chucked substrate not experiencing curvature.

19. 16. The non-transitory computer-readable storage medium of claim 15, wherein in response to the delta value satisfying the threshold criterion, one or more actions of a process recipe are performed.

20. the processing device determining a third impedance value between the substrate holder and the substrate; determining a new delta value between the third impedance value and a predetermined fourth impedance value; determining whether the delta value meets a dechucking threshold criterion; applying a fourth voltage to the substrate in response to the new delta value not meeting the dechucking threshold criterion, the fourth voltage being less than the third voltage; 20. The non-transitory computer-readable storage medium of claim 15, further performing operations including:

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