Reduced localized force during electrostatic chucking

Abstract

Semiconductor substrate support assemblies may include an electrostatic chuck body having a substrate support surface. The electrostatic chuck body may define a plurality of protrusions extending from the substrate support surface. The assemblies may include an electrode embedded within the electrostatic chuck body. The electrode may define apertures passing through the electrode that are aligned with the plurality of protrusions extending from the substrate support surface.

Description

Technology Field

[0001] This application claims the benefit and priority of U.S. Regular Application No. 17 / 205,867, filed on March 18, 2021, with the title of the invention "REDUCED LOCALIZED FORCE IN ELECTROSTATIC CHUCKING," the contents of which are incorporated herein by reference in their entirety for all purposes. Background Technology

[0002] The present technology relates to semiconductor systems, processes, and equipment. More specifically, the present technology relates to processes and systems for protecting substrates on support assemblies.

[0003] Many substrate processing systems use substrate supports, such as electrostatic chucks, combined with a base to hold the wafer during semiconductor substrate processing. Embedded electrodes can electrostatically chuck the wafer or substrate to the substrate support. Voltage can be applied to the electrodes to provide a clamping force. However, this clamping force can cause back-side damage to the substrate and generate back-side particles that can cause issues during subsequent processing.

[0004] Therefore, there is a need for improved systems and methods that can be used to improve the lifespan and performance of processing chambers and components. These and other needs are addressed by the present technology.

[0005] Semiconductor substrate support assemblies may include an electrostatic chuck body having a substrate support surface. The electrostatic chuck body may define a plurality of protrusions extending from the substrate support surface. The assemblies may include an electrode embedded within the electrostatic chuck body. The electrode may define apertures through an electrode that is aligned with the plurality of protrusions extending from the substrate support surface.

[0006] In some embodiments, the electrode may include a continuous electrode passing through the electrostatic chuck body and around a plurality of protrusions. The electrode may define an aperture that is aligned with each of the protrusions. Each aperture may be characterized by a diameter larger than the diameter of the corresponding protrusion to which the aperture is aligned. Each aperture may extend to a diameter larger than or at least about 5% larger than the diameter of the corresponding protrusion along the substrate support surface. The assemblies may include sealing bands defined around the outside of the electrostatic chuck body. The assemblies may include a gas delivery channel formed through the electrostatic chuck body. The gas delivery channel may be configured to deliver back gas to a volume defined between the plurality of protrusions and the sealing band. The gas delivery channel may be fluidically coupled to a fluid source. The fluid source may be or may contain helium gas. The assemblies may include a power supply coupled to a ground electrode embedded within the electrostatic chuck body. The power supply may be configured to provide a chucking voltage to the electrode.

[0007] Some embodiments of the present technology may include substrate support assemblies. The assemblies may include an electrostatic chuck body. The electrostatic chuck body may define a plurality of protrusions along the substrate support surface of the electrostatic chuck body. The assemblies may include an electrode embedded within the electrostatic chuck body. The electrode may define a plurality of apertures passing through the electrode. Each of the plurality of apertures may be formed to be in a straight line perpendicular to the protrusions of the plurality of protrusions along the substrate support surface.

[0008] In some embodiments, the electrode may include a continuous electrode passing through the electrostatic chuck body and around a plurality of protrusions. Each protrusion may be characterized by a diameter of about 1 mm or more. Each aperture may be characterized by a diameter larger than the diameter of the corresponding protrusion along which the aperture is aligned. Each aperture may extend to a diameter larger than or about 3% or more larger than the diameter of the corresponding protrusion along the substrate support surface. The assemblies may include sealing bands defined around the outer periphery of the electrostatic chuck body. The assemblies may include a gas delivery channel formed through the electrostatic chuck body. The gas delivery channel may be configured to deliver back gas to a volume defined between the plurality of protrusions and the sealing band. The gas delivery channel may be fluidically coupled to a fluid source. The fluid source may be or may contain helium gas. The assemblies may include a power supply coupled to a ground electrode embedded within the electrostatic chuck body. The power supply may be configured to provide a chucking voltage to the electrode.

[0009] Some embodiments of the present technology may include methods of semiconductor processing. A method may include the step of providing voltage to an electrode embedded in an electrostatic chuck body. The electrostatic chuck body may define a plurality of protrusions along the substrate support surface of the electrostatic chuck body. The electrode may define a plurality of apertures passing through the electrode. Each aperture of the plurality of apertures may be formed to be in a straight line perpendicular to the protrusions of the plurality of protrusions along the substrate support surface. A method may include the step of clamping a substrate to the electrostatic chuck body. In some embodiments, the voltage may be about 1000 V or more. The chucking force at each of the protrusions may be about 98% or less of the chucking force between each of the protrusions.

[0010] Such technology can provide numerous advantages over conventional systems and techniques. For example, processes can provide sufficient global chucking force while reducing localized chucking force at locations across the substrate support. Additionally, processes can reduce or limit back-side particles, which can facilitate downstream processing. These and other embodiments, along with many of their advantages and features, are described in more detail below and in conjunction with the accompanying drawings. Brief explanation of the drawing

[0011] Further understanding of the nature and advantages of the disclosed technology can be achieved by referring to the remainder of this specification and the drawings.

[0012] FIG. 1 illustrates a schematic plan view of an exemplary processing system according to some embodiments of the present technology.

[0013] FIG. 2 illustrates a schematic cross-sectional view of an exemplary processing system according to some embodiments of the present technology.

[0014] FIG. 3a illustrates a schematic partial cross-sectional view of an exemplary substrate support according to some embodiments of the present technology.

[0015] FIG. 3b illustrates a schematic plan view of an exemplary substrate support according to some embodiments of the present technology.

[0016] FIG. 4 illustrates selected operations of a method for semiconductor processing according to some embodiments of the present technology.

[0017] Some of the drawings are included as schematics. It should be understood that the drawings are for illustrative purposes only and should not be considered to be of actual scale unless specifically stated otherwise. Additionally, as schematics, the drawings are provided for illustrative purposes and may not include all aspects or information compared to realistic representations, and may include exaggerated material for illustrative purposes.

[0018] In the attached drawings, similar components and / or features may have the same reference label. Additionally, various components of the same type may be distinguished by having a character that distinguishes similar components follow the reference label. Where only the first reference label is used in this specification, the description is applicable to any one of the similar components having the same first reference label, regardless of the character. Specific details for implementing the invention

[0019] The plasma etching process can facilitate the removal of material from a substrate by energizing one or more constituent precursors. Process conditions can cause the substrate to detach or shift if not properly clamped. Additionally, the films formed on the substrate can cause stresses on the substrate. For example, since the processing may involve more films to create complex structures, a thicker layer of material may develop on the substrate. These generated films may be characterized by internal stresses acting on the substrate. This can cause the substrate to warp during processing, and if this is not controlled, it can lead to poor removal uniformity as well as device damage or malfunction.

[0020] An electrostatic chuck can be used to generate a clamping action on the substrate to hold the substrate during etching processes and overcome bending stress. However, as the thickness and complexity of these device structures increase, the stresses acting on the substrate increase, which may require a proportional increase in the chucking voltage. Additionally, many etching processes may be performed at relatively high temperatures that further affect the components of the chamber. For example, some etching activities may occur at temperatures of several hundred degrees or more, which can cause the substrate to thermally expand radially outward. This expansion, combined with the increased chucking voltage, can not only cause scratches to form on the back surface of the semiconductor substrate in contact with the substrate support but also cause particles to be expelled from the chuck body placed underneath.

[0021] These scratches and particles can cause numerous challenges. For example, when a substrate is removed from processing and replaced with another processed substrate in a front-open integrated pod, particles generated from the contact points can fall onto the substrates underneath, acting as defects in the films formed on those substrates. Additionally, some subsequent processing may be affected by damage. For instance, subsequent operations may include lithography. Backside damage can cause displacement of the beam projected through the substrate, which can affect the lithography process, or the particles can affect the sensitive lithography base. These issues have limited conventional technologies and caused damage to lithography components as well as wafer loss due to the impact on subsequent processing. This technology overcomes these challenges by integrating electrodes within the substrate support, which can reduce electrostatic forces at locations in contact with the substrate. This can limit backside substrate damage, particularly at increased temperatures.

[0022] While the remainder of the disclosure will routinely identify specific etching and cleaning processes utilizing the disclosed technology, it will be readily understood that the systems and methods are equally applicable to various other processes that may occur in the chambers described. Accordingly, the present technology should not be construed as being limited to use only for the etching or cleaning processes described. Before describing the methods or operations and systems of exemplary process sequences according to some embodiments of the present technology, the present disclosure will discuss one possible system and chamber that may be used with the present technology. It should be understood that the technology is not limited to the equipment described and that the processes discussed may be performed in any number of processing chambers and systems.

[0023] FIG. 1 illustrates a plan view of one embodiment of a processing system (10) of deposition, etching, baking, and / or curing chambers according to embodiments. The tool or processing system (10) depicted in FIG. 1 may include a plurality of process chambers (24a-d), a transfer chamber (20), a service chamber (26), an integrated measurement chamber (28), and a pair of load lock chambers (16a-b). The process chambers may include any number of structures or components as well as any number or combination of processing chambers.

[0024] To transport substrates between chambers, the transport chamber (20) may include a robotic transport mechanism (22). The transport mechanism (22) may have a pair of substrate transport blades (22a) each attached to the distal ends of extendable arms (22b). The blades (22a) may be used to transport individual substrates into and out of process chambers. In operation, one of the substrate transport blades, such as the blade (22a) of the transport mechanism (22), retrieves a substrate (W) from one of the loadlock chambers, such as chambers (16a-b), and transports the substrate (W) to a first stage of processing, e.g., chambers (24a-d), to a processing process as described below. Chambers may be included to perform individual or combined operations of the described technology. For example, one or more chambers may be configured to perform deposition or etching operations, while one or more other chambers may be configured to perform the described preprocessing operations and / or one or more postprocessing operations. The present technology includes any number of configurations capable of performing any number of additional fabrication operations typically performed in semiconductor processing.

[0025] If the chamber is occupied, the robot may wait until processing is completed and then remove the processed substrate from the chamber with one blade (22a) and insert a new substrate with a second blade. Once the substrate is processed, the substrate may then be moved to a second processing stage. For each movement, the transport mechanism (22) may generally have one blade for transporting the substrate and one blade that is empty to perform the substrate exchange. The transport mechanism (22) may wait in each chamber until the exchange is achieved.

[0026] Once processing is completed within the process chambers, the transport mechanism (22) can move the substrate (W) from the last process chamber and transport the substrate (W) to a cassette within the load lock chambers (16a-b). From the load lock chambers (16a-b), the substrate can be moved to the factory interface (12). The factory interface (12) can generally operate to transport substrates between the pod loaders (14a-d) and the load lock chambers (16a-b) in an atmospheric pressure clean environment. The clean environment of the factory interface (12) can generally be provided through air filtration processes, such as HEPA filtration, for example. The factory interface (12) may also include a substrate aligner / aligner that can be used to properly align the substrates prior to processing. At least one substrate robot, such as robots (18a-b), can be positioned in the factory interface (12) to transport substrates between various positions / locations within the factory interface (12) and to other locations communicating with it. The robots (18a-b) can be configured to move along a track system within the factory interface (12) from a first end of the factory interface (12) to a second end.

[0027] The processing system (10) may further include an integrated measurement chamber (28) to provide control signals, which can provide adaptive control for any of the processes performed in the processing chambers. The integrated measurement chamber (28) may include any of various measurement devices to measure various film properties such as thickness, roughness, and composition, and the measurement devices may additionally characterize grid parameters such as critical dimensions, sidewall angles, and feature height under vacuum in an automated manner.

[0028] Each of the processing chambers (24a-d) may be configured to perform one or more process steps in the fabrication of a semiconductor structure, and any number of processing chambers and combinations of processing chambers may be used on the multi-chamber processing system (10). For example, any of the processing chambers may be configured to perform a number of substrate processing operations, including any number of deposition processes such as cyclic layer deposition, atomic layer deposition, chemical vapor deposition, and physical vapor deposition, as well as other operations including etching, pre-cleaning, pretreatment, posttreatment, annealing, plasma processing, degassing, orientation, and other substrate processes. Some specific processes that may be performed in any of the chambers or in any combination of chambers may be metal deposition, surface cleaning and preparation, thermal annealing such as rapid thermal processing, and plasma processing. As will be readily understood by those skilled in the art, any other processes, including any of the processes described below, may be similarly performed in specific chambers integrated into the multi-chamber processing system (10).

[0029] FIG. 2 illustrates a schematic cross-sectional view of an exemplary processing chamber (100) suitable for patterning a material layer placed on a substrate (302) within the processing chamber (100). While the exemplary processing chamber (100) is suitable for performing a patterning process, it should be understood that aspects of the present invention may be performed in any number of chambers and that substrate supports according to the present invention may be included in etching chambers, deposition chambers, processing chambers, or any other processing chamber. The plasma processing chamber (100) may include a chamber body (105) that defines a chamber volume (101) in which a substrate can be processed. The chamber body (105) may have side walls (112) and a bottom (118), which are coupled to ground (126). The side walls (112) may have a liner (115) to protect the side walls (112) and extend the time between maintenance cycles of the plasma processing chamber (100). The dimensions of the chamber body (105) and associated components of the plasma processing chamber (100) are not limited and may generally be proportionally larger than the size of the substrate (302) to be processed in the processing chamber (100). Examples of substrate sizes, such as display or solar cell substrates, also include, in particular, 200 mm diameter, 250 mm diameter, 300 mm diameter, and 450 mm diameter.

[0030] The chamber body (105) may support a chamber cover assembly (110) to enclose the chamber volume (101). The chamber body (105) may be made of aluminum or other suitable materials. A substrate access port (113) may be formed through the side wall (112) of the chamber body (105) to facilitate the transfer of a substrate (302) into and out of the plasma processing chamber (100). The access port (113) may be coupled to a transfer chamber and / or other chambers of a substrate processing system as previously described. A pumping port (145) may be formed through the side wall (112) of the chamber body (105) and connected to the chamber volume (101). A pumping device is coupled to the chamber volume (101) through the pumping port (145) to exhaust and control the pressure within the processing volume. The pumping device may include one or more pumps and throttle valves.

[0031] A gas panel (160) may be coupled to a chamber body (105) by a gas line (167) to supply process gases within a chamber volume (101). The gas panel (160) may include one or more process gas sources (161, 162, 163, 164) and may additionally include inert gases, non-reactive gases, and reactive gases that may be utilized in any number of processes. Examples of process gases that may be provided by the gas panel (160) include (but are not limited to) hydrocarbon-containing gases including methane, sulfur hexafluoride, silicon chloride, carbon tetrafluoride, hydrogen bromide, hydrocarbon-containing gases, argon gas, chlorine, nitrogen, helium, oxygen gas, as well as any number of additional materials. Additionally, the process gases may include nitrogen, chlorine, fluorine, oxygen, and hydrogen-containing gases, such as BCl3, C2F4, C4F8, C4F6, CHF3, CH2F2, CH3F, NF3, NH3, CO2, SO2, CO, N2, NO2, N2O, and H2, among any number of additional precursors.

[0032] Valves (166) can control the flow of process gases from sources (161, 162, 163, 164) from the gas panel (160) and can be managed by a controller (165). The flow of gases supplied from the gas panel (160) to the chamber body (105) may include combinations of gases from one or more sources. The cover assembly (110) may include a nozzle (114). The nozzle (114) may have one or more ports for introducing process gases into the chamber volume (101) from sources (161, 162, 164, 163) of the gas panel (160). After the process gases are introduced into the plasma processing chamber (100), the gases may be energized to form a plasma. An antenna (148), such as one or more inductor coils, may be provided adjacent to the plasma processing chamber (100). An antenna power supply (142) can supply power to an antenna (148) through a matching circuit (141) to inductively couple energy, such as RF energy, to the process gas to maintain the plasma formed from the process gas in the chamber volume (101) of the plasma processing chamber (100). In addition to the antenna power supply (142), or alternatively, process electrodes below and / or above the substrate (302) can be used to capacitively couple RF power to the process gases to maintain the plasma within the chamber volume (101). The operation of the power supply (142) can be controlled by a controller, such as a controller (165), which also controls the operation of other components within the plasma processing chamber (100).

[0033] A substrate support pedestal (135) may be placed in the chamber volume (101) to support the substrate (302) during processing. The substrate support pedestal (135) may include an electrostatic chuck (122) for holding the substrate (302) during processing. The electrostatic chuck (ESC) (122) may use electrostatic attraction to hold the substrate (302) to the substrate support pedestal (135). The ESC (122) may be powered by an RF power supply (125) integrated with a matching circuit (124). The ESC (122) may include an electrode (121) embedded within a dielectric body. The electrode (121) can be coupled to an RF power supply (125) and can provide a bias that attracts plasma ions formed by process gases within the chamber volume (101) to the substrate (302) and ESC (122) mounted on the pedestal. The RF power supply (125) can pulse or cycle on and off during the processing of the substrate (302). The ESC (122) may have an isolator (128) for the purpose of making the sidewalls of the ESC (122) less attractive to the plasma in order to increase the maintenance life cycle of the ESC (122). Additionally, the substrate support pedestal (135) may have a cathode liner (136) to protect the sidewalls of the substrate support pedestal (135) from plasma gases and to extend the time between maintenance of the plasma processing chamber (100).

[0034] The electrode (121) may be coupled to a power source (150). The power source (150) may provide a chucking voltage of about 200 V to about 2000 V to the electrode (121). The power source (150) may also include a system controller for controlling the operation of the electrode (121) by directing a DC current to the electrode (121) to chuck and de-chuck the substrate (302). The ESC (122) may include a heater placed within a pedestal and connected to a power source for heating the substrate, while the cooling base (129) supporting the ESC (122) may include conduits for circulating a heat transfer fluid to maintain the temperature of the ESC (122) and the substrate (302) placed on the ESC (122). The ESC (122) may be configured to operate within a temperature range required by the thermal budget of the device fabricated on the substrate (302). For example, the ESC (122) may be configured to maintain the substrate (302) at a temperature of about -150°C or lower to about 500°C or higher depending on the process being performed.

[0035] A cooling base (129) may be provided to assist in temperature control of the substrate (302). To mitigate process drift and time, the temperature of the substrate (302) may be maintained substantially constant by the cooling base (129) throughout the time the substrate (302) is in the cleaning chamber. In some embodiments, the temperature of the substrate (302) may be maintained at temperatures of about -150°C to about 500°C throughout subsequent cleaning processes, but any temperature may be utilized. A covering ring (130) may be placed on the ESC (122) and along the periphery of the substrate support pedestal (135). The covering ring (130) may be configured to confine the etching gas to a desired portion of the exposed top surface of the substrate (302) while shielding the top surface of the substrate support pedestal (135) from the plasma environment inside the plasma processing chamber (100). The lift pins are optionally translated through the substrate support pedestal (135) to lift the substrate (302) over the substrate support pedestal (135), thereby enabling access to the substrate (302) by a transfer robot or other suitable transfer mechanism as previously described.

[0036] The controller (165) can be utilized to control a process sequence that controls the gas flow from the gas panel (160) to the plasma processing chamber (100) and other process parameters. Software routines convert the CPU into a special-purpose computer, such as a controller, capable of controlling the plasma processing chamber (100) so that processes are performed in accordance with the present disclosure when executed by the CPU. Software routines can also be stored and / or executed by a second controller that may be associated with the plasma processing chamber (100).

[0037] FIG. 3a illustrates a schematic partial cross-sectional view of an exemplary substrate support (300) according to some embodiments of the present invention. For example, the substrate support (300) may exemplify a portion of the support pedestal (135) described above and may include any aspect of the support assembly, such as electrodes, heaters, or any other components that may be incorporated into the substrate supports. The substrate support (300) may also exemplify additional details of the support assemblies described above. The substrate support (300) may exemplify a generalized cross-section of a support structure according to embodiments of the present invention, which may extend to any length or diameter across the substrate covered by the present invention. It will be understood that the substrate support (300) is not exemplified at any particular scale and is included merely to exemplify aspects of the present invention.

[0038] The substrate support (300) may include a number of components bonded, welded, joined, or otherwise coupled to each other. As illustrated, a number of additional components may be included, but the substrate support (300) may include an electrostatic chuck body (305) or a top puck, which may be coupled to a power source to provide electrostatic chucking or clamping of the substrate on the surface of the puck. In some embodiments, components integrated within the top puck may not be exposed to processing materials and may be retained entirely within the chuck body. The electrostatic chuck body (305) may define a substrate support surface (307) and may be characterized by a thickness and length or diameter depending on the specific geometry of the chuck body. In some embodiments, the chuck body may be elliptical and may be characterized by one or more radial dimensions through the chuck body from a central axis. It will be understood that the top puck may be of any geometry and may define any length from the central position of the chuck body when radial dimensions are discussed. Although any surface topography may be covered by the present invention, in some embodiments, the electrostatic chuck body (305) may define a number of mesas or protrusions (310) on which a substrate (312) can be seated. Between the protrusions of the puck, there may be recessed zones as illustrated.

[0039] The electrostatic chuck body (305) may include an electrode (315) which may be a DC electrode embedded within the chuck body in proximity to the substrate support surface. The electrode (315) may be electrically coupled to a power supply (320). The power supply (320) may be configured to provide energy or voltage to the electrically conductive chuck electrode (315). This may be operated to form a plasma of a precursor within a processing zone of a semiconductor processing chamber in which the substrate support assembly is located, but other plasma operations may be similarly sustained. For example, the electrode (315) may also be a chucking electrode that acts as an electrical ground for a capacitive plasma system including an RF source electrically coupled to a showerhead or other chamber component. For example, the electrode (315) may act as a ground path for RF power from an RF source coupled elsewhere in the chamber, and may also act as an electrical bias for the substrate to provide electrostatic clamping of the substrate on the substrate support surface. The power supply (320) may include a number of other electrical components configured to provide a filter, a power supply, and a chucking voltage.

[0040] During operation, the substrate (312) may come into at least partial contact with the substrate support surface of the electrostatic chuck body, which can create a contact gap and essentially create a capacitive effect between the surface of the pedestal and the substrate. A voltage may be applied to the contact gap, which can create an electrostatic force for chucking. The power supply (320) may provide charge from the electrode to the substrate support surface where electric charge may be accumulated, which can create a charge layer having Coulomb attraction with the opposite charge on the substrate and electrostatically hold the substrate against the substrate support surface of the chuck body. This charge transfer may be caused by a current flowing through the dielectric material of the chuck body based on finite resistance in the dielectric for Johnson-Rahbek type chucking, which may be used in some embodiments of the present technology.

[0041] In some embodiments, the electrostatic chuck body (305) may be an insulating or dielectric material. For example, oxides, nitrides, carbides, and other materials may be used to form the components. Exemplary materials may include aluminum oxide, aluminum nitride, silicon carbide, tungsten carbide, and any other metal or transition metal oxide, nitride, carbide, boride, or titanate, as well as ceramics comprising combinations of these materials and other insulating or dielectric materials. Different grades of ceramic materials may be used to provide composites configured to operate in specific temperature ranges, and accordingly, in some embodiments, different grades of similar materials may be used for the top puck and stem. In some embodiments, dopants may be incorporated to adjust electrical properties as further described below. Exemplary dopant materials may include yttrium, magnesium, silicon, iron, calcium, chromium, sodium, nickel, copper, zinc, or any number of other elements known to be incorporated within the ceramic or dielectric material.

[0042] During semiconductor processing, one or more back gases may flow into the substrate support (300) through one or more gas delivery channels (330) extending, for example, through the stem of the substrate support. For example, a gas delivery system (335) which may include any number of valves, controllers and / or piping may provide one or more gases that can flow within and around the gaps in the substrate support. By providing positive pressure of a fluid, such as an inert or non-reactive gas, within the substrate support, improved heat transfer within the substrate support may be maintained. Any number of materials may be used as heat transfer back gases, and in some embodiments, helium, nitrogen, argon, other noble gases, or other process gases may be utilized. Helium may feature improved heat transfer compared to other precursors due to the relatively low molecular weight of the fluid. For example, thermal conductivity may increase as molecular weight decreases, and accordingly, helium may facilitate improved temperature uniformity through the structure when flowing within the gaps of the device. In some embodiments, helium may be enhanced with one or more other precursors capable of adjusting the thermal conductivity of the back gas. By providing nitrogen, argon, or other materials, the heat transfer characteristics of the fluid can be adjusted for specific processes.

[0043] During substrate processing, the flow rate and / or pressure of the back gas being delivered may be maintained at a relatively low level and may be delivered at a flow rate that maintains a pressure amount to improve thermal conductivity and to minimize leakage into the processing zone through the substrate support. Consequently, in some embodiments, the flow rate may be maintained at about 20 sccm or less, about 15 sccm or less, about 12 sccm or less, about 10 sccm or less, about 9 sccm or less, about 8 sccm or less, about 7 sccm or less, about 6 sccm or less, about 5 sccm or less, about 4 sccm or less, about 3 sccm or less, about 2 sccm or less, about 1 sccm or less, or less, but the flow rate may be maintained such that the controller of the gas delivery system (335) operates above a threshold.

[0044] As previously described, the substrate (312) may be positioned on the substrate support surface (307) and may come into contact with each of the protrusions (310), and additionally may extend at least partially across the sealing band (325), which may extend around an outer area of ​​the chuck body and allow for a certain degree of sealing of a volume defined between and around the protrusions (310) and the substrate. The sealing band (325) may extend vertically from the surface of the chuck body and may generally extend circumferentially or in a peripheral pattern around the chuck body. In some embodiments, the protrusions (310) may be characterized by a diameter or width of about 1 mm, about 2 mm, about 3 mm or greater, and in some embodiments, may include a combination of protrusions characterized by a diameter of about 1 mm or more and protrusions characterized by a diameter of about 2 mm or more. The protrusions may be characterized by any number of geometric structures and profiles in embodiments of the present technology. For an exemplary substrate support assembly, the substrate support surface within the sealing band or within the internal region may define about 250 or more protrusions, about 500 or more protrusions, about 750 or more protrusions, about 1,000 or more protrusions, about 1,250 or more protrusions, about 1,500 or more protrusions, about 1,750 or more protrusions, about 2,000 or more or more protrusions. The protrusions may be defined as any number of formations or patterns including uniform patterns as well as general distributions across the surface.

[0045] By creating protrusions according to some embodiments of the present technology, the percentage of contact along the surface of the substrate may be increased to about 1.0% or more, about 1.5% or more, about 2.0% or more, about 2.5% or more, about 3.0% or more, about 3.5% or more, about 4.0% or more, about 4.5% or more, about 5.0% or more, or greater than. The percentage of contact may be maintained at about 10% or less to limit leakage current below the previously mentioned ranges, and contact may be limited to about 8% or less, about 6% or less, about 5% or less, or less. Additionally, the protrusions themselves may be adjusted to affect the effects caused on the substrates.

[0046] The power supply (320) may provide a voltage for clamping the substrate (312) and may be configured to provide a voltage of about 200 V or more, about 400 V or more, about 600 V or more, about 800 V or more, about 1000 V or more, about 1200 V or more, about 1400 V or more, about 1600 V or more, about 1800 V or more, about 2000 V or more, or more. As previously described, these high voltages may increase wear between the substrate and the protrusions on which the substrate rests. However, by reducing the voltage, the clamping force may be insufficient to overcome substrate warping and may also allow a certain amount of back gas leakage from the sealing band. In some embodiments, the protrusions (310) may feature rounded corners to limit back damage to the substrate, but increased particles may still occur. Therefore, the present technology can utilize an electrode configured to reduce the local chucking voltage at contact points between the chuck body and the substrate.

[0047] The electrode (315) may feature a continuous conductive body extending through the chuck body. However, in some embodiments, the electrode (315) may define one or more apertures including a plurality of apertures passing through the electrode, which may be formed in alignment with a plurality of protrusions (310) extending from the substrate support surface. Thus, while the electrode (315) may still extend continuously through the electrostatic chuck body, it may extend around some or all of the plurality of protrusions, including an embodiment in which an aperture passing through the electrode vertically in alignment with each of the protrusions is defined as illustrated. Additionally, in some embodiments, and unlike a mesh electrode, the apertures passing through the electrode may be limited to locations in alignment with the protrusions.

[0048] FIG. 3b illustrates a schematic plan view of an exemplary substrate support (300) according to some embodiments of the present invention and may illustrate additional details of apertures defined by electrodes. Although electrodes (315) may be shown in the drawing, this is for illustrative purposes only, and it should be understood that in the encompassed embodiments, electrodes may be completely embedded within the chuck body and may not be visible within the component. As illustrated, the electrostatic chuck body (305) may include a sealing band (325) that extends around the substrate support surface and upon which the substrate can be seated as discussed above. The sealing band (325) may define an internal area where a plurality of protrusions (310) may be defined. FIG. 3b is illustrated only to illustrate aspects of the present invention and it should be understood that it may include hundreds or thousands of protrusions across the surface of the substrate support.

[0049] The electrode (315) may be a continuous conductive body extending across the substrate support and may extend around the protrusions (310). The electrode (315) may extend to or beyond the inner radial edge of the sealing band (325), but as illustrated in some embodiments, the outer diameter of the electrode (315) may be smaller than the inner diameter of the sealing band (325). Similarly, apertures (340), each of which may be formed in alignment with the corresponding protrusion (310), may be characterized by a diameter larger than the diameter of the corresponding protrusion (310) to which the aperture may extend around. By limiting the overlap of the electrode with any location where contact with the substrate may occur, localized chucking force may be reduced at the contact points, while global chucking force across the substrate may be maintained. Thus, in some embodiments, increased chucking voltages may be applied, while scratching and particle generation may be reduced or limited.

[0050] The difference between the diameter of the protrusion and the corresponding aperture passing through the electrode may be about 0.10 mm or more, about 0.15 mm or more, about 0.20 mm or more, about 0.25 mm or more, about 0.30 mm or more, about 0.35 mm or more, about 0.40 mm or more, about 0.45 mm or more, about 0.50 mm or more, about 0.55 mm or more, about 0.60 mm or more, about 0.65 mm or more, about 0.70 mm or more, about 0.75 mm or more, about 0.80 mm or more, about 0.85 mm or more, about 0.90 mm or more, about 0.95 mm or more, about 1.00 mm or more or more, but as the aperture size continues to increase, the clamping force at the contact locations may decrease. Consequently, in some embodiments, the difference between the diameter of the protrusion and the corresponding aperture passing through the electrode may be about 1.0 mm or less. Similarly, depending on the size of the protrusion, the corresponding aperture may extend its diameter along the substrate support surface by about 1% or more than the diameter of the corresponding protrusion, and may extend its diameter by about 1% or more, about 2% or more, about 3% or more, about 4% or more, about 5% or more, about 6% or more, about 7% or more, about 8% or more, about 9% or more, about 10% or more, about 15% or more, about 20% or more, about 25% or more, about 30% or more, about 35% or more, about 40% or more, about 45% or more, about 50% or more, or more than that.

[0051] Additionally, the gap between any two protrusions may be characterized by a first length, and the length of the electrode within the gap may be characterized by a second length that is smaller than the first length. In some embodiments, the second length may be about 99% or less of the first length, about 95% or less of the first length, about 90% or less of the first length, about 85% or less of the first length, about 80% or less of the first length, about 75% or less of the first length, about 70% or less of the first length, about 65% or less of the first length, about 60% or less of the first length, about 55% or less of the first length, about 50% or less of the first length, or less than the first length. This may facilitate reducing the clamping force on the edges of the protrusions during operations. To maintain separation between the electrode and the protrusions in vertically separated planes, the electrode may be deposited by physical vapor deposition, screen printing, chemical vapor deposition, or any other process that allows a pattern to be formed—this pattern corresponds to the pattern of the protrusions of the substrate support.

[0052] The substrate supports described above may be used during methods according to embodiments of the present technology. FIG. 4 illustrates a method (400) for processing a semiconductor substrate, the operations of which may be performed in one or more chambers (100) integrated into a multi-chamber processing system (10), for example, as previously described. Any other chamber capable of performing one or more operations of any described method or process may also be utilized. Additionally, the method may be performed in chambers or systems comprising substrate supports that may be the previously described substrate support (300) or may include any aspect of the substrate support (300). The method (400) may include one or more operations prior to the initiation of the mentioned method operations, and the one or more operations may include front-end processing, deposition, etching, polishing, cleaning, or any other operations that may be performed prior to the described operations. The method may include a number of optional operations as shown in the drawings, the optional operations may or may not be specifically associated with the method according to the present technology. For example, many of the operations are described to provide a broader range of semiconductor processes, but are not critical to the present invention, or can be performed by alternative methods as will be further discussed below.

[0053] During the processing operations of the method (400), in an optional operation (405), the substrate may be positioned on a substrate support such as the substrate support (300) described above. A voltage may be applied to the electrode as previously discussed, which may electrostatically clamp the substrate to the electrostatic chuck body in operation (410) and clamp the substrate along the protrusions and / or sealing band as previously described. Depending on the applied voltage, the clamping force at any specific location along the substrate may be about 50 N or more, about 100 N or more, about 150 N or more, about 200 N or more, about 250 N or more, about 300 N or more, about 350 N or more, about 400 N or more, about 450 N or more, about 500 N or more, about 550 N or more, about 600 N or more, about 650 N or more, about 700 N or more, or greater than that. As previously described, by creating apertures in the electrode around each substrate support contact location, the localized chucking force at each protrusion may be about 99% or less of the global chucking force provided by the electrode, about 98% or less of the chucking force, about 97% or less of the chucking force, about 96% or less of the chucking force, about 95% or less of the chucking force, about 94% or less of the chucking force, about 93% or less of the chucking force, about 92% or less of the chucking force, about 91% or less of the chucking force, about 90% or less of the chucking force, about 85% or less of the chucking force, or about 80% or less of the chucking force. By utilizing an electrode having specially located apertures as described, the present technology can limit scratching and particle transfer on the back surface of the substrate.

[0054] In the preceding description, numerous details have been presented for the purpose of explanation to provide an understanding of various embodiments of the present technology. However, it will be obvious to those skilled in the art that certain embodiments may be practiced without some of these details or with additional details.

[0055] Although disclosed in various embodiments, it will be recognized by those skilled in the art that various modifications, alternative structures, and equivalents may be used without departing from the spirit of the embodiments. Additionally, to avoid unnecessarily obscuring the art, many well-known processes and elements have not been described. Accordingly, the above description should not be understood as limiting the scope of the art.

[0056] Where a range of values ​​is given, each value existing between the upper and lower limits of such range is interpreted as also specifically described up to one-tenth of the single-digit value of the smallest digit of the lower limit, unless otherwise clearly indicated in the context. Any narrower range existing between any specified value within a specified range or any unspecified value belonging to such range and any other specified value within such specified range or any other value belonging to such range is included. The upper and lower limits of such sub-ranges may independently be included in or excluded from such ranges, and each range is also included in the description insofar as any specifically excluded limit is in the specified range, whether one or both of the upper and lower limits are included in such sub-ranges or both are excluded from such sub-ranges. Where a specified range includes one or both of the limits, ranges excluding one or both of the limits so included are also included.

[0057] As used in the present and appended claims, singular forms (“a,” “an,” and “the”) include multiple references unless the context clearly indicates otherwise. Thus, for example, a reference to “layer” includes multiple such layers, and a reference to “protrusion” includes one or more precursors and equivalents of the protrusions known to those skilled in the art, etc.

[0058] Additionally, as used herein and in the following claims, the words “comprise,” “comprising,” “contain,” “containing,” “include,” and “including” are intended to specify the presence of the stated features, integers, components, or actions, but do not exclude the presence or addition of one or more other features, integers, components, actions, acts, or groups.

Claims

Claim 1 A substrate support assembly comprising: an electrostatic chuck body including a sealing band extending around an outer edge of the electrostatic chuck body and defining an inner region—the inner region defines a substrate support surface, and the electrostatic chuck body defines a plurality of protrusions extending from the substrate support surface—; and an electrode embedded within the electrostatic chuck body—the electrode defines apertures passing through the electrode in a straight line with the plurality of protrusions extending from the substrate support surface—the electrode includes an electrode that passes through the entire inner region up to an inner radial edge of the sealing band and is continuous around the plurality of protrusions, wherein the difference between the diameter of each protrusion and the diameter of the corresponding aperture passing through the electrode is 0.10 mm or more and 1.0 mm or less. Claim 2 delete Claim 3 A substrate support assembly according to claim 1, wherein the electrode defines an aperture that is in a straight line with each of the protrusions of the plurality of protrusions. Claim 4 A substrate support assembly according to paragraph 3, wherein each aperture is characterized by a diameter larger than the diameter of a corresponding protrusion that forms a straight line with the aperture. Claim 5 In paragraph 4, a substrate support assembly wherein each aperture extends to a diameter greater than or greater than 5% greater than the diameter of a corresponding protrusion along the substrate support surface. Claim 6 In claim 1, the sealing band is a substrate support assembly extending around the outer edge of the inner region. Claim 7 A substrate support assembly according to claim 6, further comprising a gas delivery channel formed through the electrostatic chuck body, wherein the gas delivery channel is configured to deliver rear gas to a volume defined between the plurality of protrusions and the sealing band. Claim 8 In claim 7, the gas delivery channel is fluidically coupled with a fluid source, and the fluid source comprises a helium gas, forming a substrate support assembly. Claim 9 A substrate support assembly according to claim 1, further comprising a power supply coupled to an electrode embedded within the electrostatic chuck body, wherein the power supply is configured to provide a chucking voltage to the electrode. Claim 10 A substrate support assembly comprising: an electrostatic chuck body — the electrostatic chuck body defines a plurality of protrusions along a substrate support surface of the electrostatic chuck body, and the electrostatic chuck body includes a sealing band extending around an outer edge of the electrostatic chuck body and defining an inner region, wherein the inner region defines the substrate support surface — and an electrode embedded within the electrostatic chuck body — the electrode defines a plurality of apertures passing through the electrode, and each aperture of the plurality of apertures is formed to be in a straight line perpendicular to the protrusions of the plurality of protrusions along the substrate support surface — and the electrode includes an electrode that passes through the entire inner region up to an inner radial edge of the sealing band and is continuous around the plurality of protrusions, wherein the difference between the diameter of each protrusion and the diameter of the corresponding aperture passing through the electrode is 0.10 mm or more and 1.0 mm or less. Claim 11 delete Claim 12 A substrate support assembly according to claim 10, wherein each protrusion is characterized by a diameter of 1 mm or more. Claim 13 A substrate support assembly according to claim 12, wherein each aperture is characterized by a diameter larger than the diameter of a corresponding protrusion in which the aperture forms a straight line. Claim 14 In paragraph 13, a substrate support assembly in which each aperture extends to a diameter greater than or greater than 3% greater than the diameter of a corresponding protrusion along the substrate support surface. Claim 15 In claim 10, the sealing band is a substrate support assembly extending around the outer edge of the inner region. Claim 16 A substrate support assembly according to claim 15, further comprising a gas delivery channel formed through the electrostatic chuck body, wherein the gas delivery channel is configured to deliver a rear gas to a volume defined between the plurality of protrusions and the sealing band, and the gas delivery channel is fluidically coupled to a fluid source, wherein the fluid source comprises helium gas. Claim 17 A substrate support assembly according to claim 10, further comprising a power supply coupled to an electrode embedded within the electrostatic chuck body, wherein the power supply is configured to provide a chucking voltage to the electrode. Claim 18 A semiconductor processing method comprising the step of providing voltage to an electrode embedded in an electrostatic chuck body, wherein the electrostatic chuck body defines a plurality of protrusions along a substrate support surface of the electrostatic chuck body, the electrostatic chuck body includes a sealing band extending around an outer edge of the electrostatic chuck body and defining an inner region, wherein the inner region defines the substrate support surface, and the electrode defines a plurality of apertures passing through the electrode, wherein each aperture of the plurality of apertures is formed to be in a straight line perpendicular to the protrusions of the plurality of protrusions along the substrate support surface, and the electrode includes a continuous electrode passing through the entire inner region up to an inner radial edge of the sealing band and around the plurality of protrusions; and the step of clamping a substrate to the electrostatic chuck body, wherein the difference between the diameter of each protrusion and the diameter of the corresponding aperture passing through the electrode is 0.10 mm or more and 1.0 mm or less. Claim 19 A semiconductor processing method according to claim 18, wherein the voltage is 1000V or higher. Claim 20 A semiconductor processing method according to claim 18, wherein the chucking force at each of the plurality of protrusions is 98% or less of the chucking force between each of the plurality of protrusions.

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