Use of signal filtering methods in high TCR-based control

Abstract

A controller for controlling the temperature of a first substrate support in a substrate processing system includes a resistance calculation module for calculating a first resistance of a first heater element among a plurality of heater elements of the first substrate support, a temperature calculation module for calculating a first temperature of the first heater element based on the calculated first resistance, and a filter module for filtering a first signal corresponding to the calculated first resistance. The temperature calculation module causes the filter module to selectively filter the first signal in response to a determination of whether at least one condition associated with the operation of the substrate processing system is satisfied.

Description

Technology Field

[0001] The present disclosure relates to temperature control during substrate processing. Background Technology

[0002] The description of the background technology provided in this specification is intended to provide the general context of the present disclosure. Neither the work of the inventors named in this specification to the extent described in this background technology section, nor aspects of the present technology that may not otherwise be recognized as prior art at the time of filing, are explicitly or implicitly recognized as prior art to the present disclosure.

[0003] Substrate processing systems may be used to process substrates such as semiconductor wafers. Examples of substrate processing include etching, deposition, photoresist removal, etc. During processing, the substrate is placed on a substrate support such as an electrostatic chuck. One or more process gases may be introduced into the processing chamber. One or more processing gases may be delivered to the processing chamber by a gas delivery system. In some systems, the gas delivery system includes a manifold connected to a showerhead located within the processing chamber by one or more conduits.

[0004] Cross-reference regarding related applications

[0005] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 180,883 filed on April 28, 2021. The full disclosure of the aforementioned application is incorporated herein by reference.

[0006] A controller for controlling the temperature of a first substrate support in a substrate processing system includes a resistance calculation module for calculating a first resistance of a first heater element among a plurality of heater elements of the first substrate support, a temperature calculation module for calculating a first temperature of the first heater element based on the calculated first resistance, and a filter module for filtering a first signal corresponding to the calculated first resistance. The temperature calculation module causes the filter module to selectively filter the first signal in response to a determination of whether at least one condition associated with the operation of the substrate processing system is satisfied.

[0007] In other features, at least one condition corresponds to the operation of a substrate processing system associated with a temperature change of the first heater element. A temperature calculation module determines whether a temperature change of the first heater element is expected based on a calculated first resistance, and in response to the determination that a temperature change is not expected, causes a filter module to selectively filter the first signal. A temperature calculation module determines whether the rate of temperature change of the first heater element exceeds a threshold value based on a calculated first resistance, and in response to the determination that the rate of temperature change exceeds the threshold value, causes a filter module to selectively filter the first signal.

[0008] In other features, the temperature calculation module compares a first temperature change of the first heater element with a second temperature change of the second heater element and, based on the comparison, causes the filter module to selectively filter the first signal. The second heater element is located within the second substrate support. The filter module applies a resistance offset to the first signal in response to a determination of whether at least one condition associated with the operation of the substrate processing system is satisfied. The controller further includes a temperature control module configured to control the power supplied to the first heater element based on the first signal.

[0009] In other features, the resistance calculation module receives a first current corresponding to the first heater element, receives a first voltage corresponding to the first heater element, and calculates a first resistance based on the first voltage and the first current. The temperature calculation module calculates a first temperature based on the calculated first resistance and the temperature coefficient of the resistance of the first heater element.

[0010] The system includes a resistance calculation module for receiving a current corresponding to a heater element within a substrate support and a voltage corresponding to the heater element, and for calculating the resistance of the heater element based on the voltage and current; a temperature calculation module for calculating the temperature of the heater element based on the calculated resistance; and a filter module for filtering a signal corresponding to the calculated resistance. The temperature calculation module causes the filter module to selectively filter the signal in response to a determination of whether at least one condition associated with a change in the temperature of the heater element is satisfied. The system further includes a temperature control module configured to control the power supplied to the heater element based on the signal when filtered by the filter module.

[0011] In other features, the temperature calculation module determines, based on the calculated first resistance, at least one of whether a change in the temperature of the heater element is expected and whether the rate of change in the temperature of the heater element exceeds a threshold value. The temperature calculation module causes the filter module to selectively filter the signal in response to the determination that a change in the temperature of the heater element is not expected, the determination that the rate of change in the temperature of the heater element exceeds a threshold value, and the determination that the change in the temperature of the heater element is not within the range of the temperature change of another heater element.

[0012] A method for controlling the temperature of a first substrate support in a substrate processing system includes the steps of calculating a first resistance of a first heater element of a plurality of heater elements of the first substrate support, calculating a first temperature of the first heater element based on the calculated first resistance, and selectively filtering a first signal corresponding to the calculated first resistance in response to a determination of whether at least one condition associated with the operation of the substrate processing system is satisfied.

[0013] In other features, at least one condition corresponds to the operation of a substrate processing system associated with a temperature change of a first heater element. The method further includes the step of determining whether a temperature change of the first heater element is expected based on a calculated first resistance, and the step of selectively filtering a first signal in response to the determination that a temperature change is not expected. The method further includes the step of determining whether the rate of temperature change of the first heater element exceeds a threshold value based on a calculated first resistance, and the step of selectively filtering a first signal in response to the determination that the rate of temperature change exceeds a threshold value.

[0014] In other features, the method further includes the step of comparing a first temperature change of a first heater element with a second temperature change of a second heater element and the step of selectively filtering a first signal based on the comparison. The second heater element is located within a second substrate support. The method further includes the step of controlling power supplied to the first heater element based on the first signal.

[0015] Further applicable areas of the present disclosure will become apparent from the detailed description, claims, and drawings. The detailed description and specific examples are intended only for illustrative purposes and are not intended to limit the scope of the present disclosure. Brief explanation of the drawing

[0016] The present disclosure will be more fully understood from the detailed description and the accompanying drawings. FIG. 1 is a functional block diagram of an exemplary substrate processing system according to the present disclosure. FIG. 2a is an exemplary substrate support according to the present disclosure. FIG. 2b is a plan view of an exemplary substrate support according to the present disclosure. FIG. 3 is a functional block diagram of an exemplary controller according to the present disclosure. FIG. 4 illustrates steps of an exemplary method for selectively filtering signals corresponding to resistances calculated in a substrate support according to the present disclosure. In drawings, reference numbers may be reused to identify similar and / or identical elements. Specific details for implementing the invention

[0017] Film deposition and etching processes may vary over a spatial distribution (i.e., xy coordinates in a horizontal plane). For example, in deposition processes, the properties of the deposited film vary over a spatial distribution. Conversely, in etching processes, the amount of etching may vary over a spatial distribution.

[0018] The properties of etched and deposited films (e.g., deposited atomic layer deposition (ALD) films, plasma enhanced chemical vapor deposition (PECVD) films, etc.) may be affected by the temperature of the substrate during deposition. Therefore, a substrate support (e.g., a pedestal including a planar top surface configured to support the substrate) may implement a temperature control system. For example, during an ALD process (e.g., deposition of an oxide film), the substrate is arranged on the pedestal. Typically, the ALD pedestal includes a single temperature-controlled zone. In some examples, the ALD pedestal may include multiple temperature-controlled zones (e.g., a center, an inner zone, and an outer zone). A heater layer may be embedded within the top layer of the ALD pedestal. The heater layer may be configured to receive voltage / current and function as a resistive heater to heat the pedestal and the substrate placed thereon. The heater layer may be configured to heat a single zone or to individually heat multiple zones of the pedestal, such as an inner zone and an outer zone.

[0019] Typically, a pedestal comprising a single zone or multiple zones may include only a single temperature sensor placed in the central area of ​​the pedestal due to manufacturing and architectural constraints. In other examples, the pedestal may not include any temperature sensors. Consequently, precise control of the pedestal temperature may be limited.

[0020] In some examples, the temperature control system may be configured to calculate the temperatures of the heater elements and each zone of the pedestal based on the temperature coefficient of resistance (TCR) of each heater element, voltage, and current. For example, the pedestal may include a heater layer comprising heater elements having a high TCR (e.g., 1.0% or higher). For example, the heater elements may include molybdenum and nickel heater elements, but are not limited to these. The TCR may be positive or negative. A positive TCR is associated with increased resistance as the temperature rises. Conversely, a negative TCR is associated with decreased resistance as the temperature rises.

[0021] Accordingly, the total resistance of the heater layer (i.e., one or more heater elements of the corresponding heater layer) represents the temperature of the heater layer. The current supplied to the heater layer and the voltage across the heater layer may be measured to calculate the resistance of the heater layer. The respective temperatures of the outer zone and the inner zone may also be calculated based on changes in the resistance of the heater layer. In this manner, the temperatures of different zones of the substrate support (and thus, the substrate regions of the different zones) may be controlled independently of each other and independently of the thermal load and other system transients.

[0022] Measurement signals representing current and voltage are used to calculate resistance. System noise and false variations in resistance can lead to inaccurate resistance and temperature calculations, as well as defective temperature control. For example, system variations unrelated to temperature changes (e.g., component wear or other structural variations) can cause permanent or intermittent changes in resistance. Therefore, any resistance changes not triggered by actual temperature variations can lead to inaccurate temperature control.

[0023] The temperature control system may include one or more filters (e.g., first-order, linear filters). For example, the filters may be configured to filter noise from measurement signals. However, the filters do not filter resistance changes that may be caused by variations such as oxidation, component wear, loosening of fittings, connections, and splices.

[0024] Temperature control systems and methods according to the present disclosure implement a filter system configured to distinguish between noise and resistance changes caused by structural variations. For example, the filter system implements both linear and nonlinear filters. The filter system selectively filters measurement signals to remove both noise and resistance changes caused by system variations unrelated to temperature changes while preserving signal characteristics related to actual temperature changes.

[0025] Now, referring to FIG. 1, an example of a substrate processing system (100) comprising a substrate support (e.g., a pedestal such as an ALD or PECVD pedestal) (104) according to the present disclosure is shown. The substrate support (104) is disposed within a processing chamber (108). A substrate (112) is disposed on the substrate support (104) during processing.

[0026] A gas delivery system (120) includes gas sources (122-1, 122-2, ..., and 122-N) (collectively gas sources (122)) connected to valves (124-1, 124-2, ..., and 124-N) (collectively valves (124)) and mass flow controllers (126-1, 126-2, ..., and 126-N) (collectively MFCs (mass flow controllers) (126)). The MFCs (126) control the flow of gases from the gas sources (122) to a manifold (128) where the gases are mixed. The output of the manifold (128) is supplied to the manifold (136) through an optional pressure regulator (132). The output of the manifold (136) is input to the multi-injector showerhead (140). Although manifolds (128 and 136) are shown, a single manifold may also be used.

[0027] The substrate support (104) includes a plurality of zones. As illustrated, the substrate support (104) includes an inner (central) zone (144) and an outer zone (148). The temperature of the substrate support (104) may be controlled by using one or more heater elements (e.g., resistive heaters) (160) disposed within the substrate support (104), as described in more detail below. In other examples, the substrate support (204) may include more (e.g., three or more) zones or a single zone.

[0028] In some examples, the substrate support (104) may include coolant channels (164). Cooling fluid is supplied to the coolant channels (164) from the fluid reservoir (168) and the pump (170). Pressure sensors (172, 174) may be placed in the manifold (128) or the manifold (136), respectively, to measure pressure. A valve (178) and a pump (180) may be used to exhaust reaction materials from the processing chamber (108) and / or to control the pressure within the processing chamber (108).

[0029] The controller (182) may include a dose controller (184) that controls the dosing provided by the multi-injector showerhead (140). The controller (182) also controls the gas delivery from the gas delivery system (120). The controller (182) controls the pressure within the processing chamber and / or the exhaust of the reaction materials using the valve (178) and the pump (180). The controller (182) controls the temperature of the substrate support (104) and the substrate (112) based on temperature feedback (e.g., from sensors (not shown) within the substrate support and / or sensors (not shown) measuring the coolant temperature).

[0030] One or more signals provided to and from the substrate support (104) (e.g., between the substrate support (104) and the controller (182)) are routed through a filter box (188). For example, the measurement signals (192) may represent the respective voltages and currents of the heater elements (160). The controller (182) is configured to calculate the temperatures of the respective zones of the heater elements (160) and the substrate support (104) based on the TCR, voltage, and current of each of the heater elements (160) based partially on the measurement signals (192). The controller (182) according to the present disclosure is further configured to selectively filter the resistance values ​​calculated using the measurement signals (192) as described in more detail below.

[0031] Referring to FIG. 2a and FIG. 2b, a simplified exemplary substrate support (200) according to the present disclosure is illustrated schematically and in a plan view, respectively. The substrate support (200) comprises a conductive base plate (204) and a heater layer (208). For example, the heater layer (208) may be formed on the upper surface (212) of the base plate (204). The base plate (204) is disposed within an upper plate (e.g., an aluminum diffuser plate) (216). Thus, the heater layer (208) is embedded within the substrate support (200). A substrate (220) may be disposed on the substrate support (200) for processing (e.g., for ALD or PECVD processing).

[0032] As illustrated, the substrate support (200) (and thus, the heater layer (208)) comprises two zones: an inner, central zone (224-1) and an outer zone (224-2), collectively referred to as zones (224). The inner zone (224-1) and the outer zone (224-2) each comprise resistive heater elements (228-1 and 228-2), collectively referred to as heater elements (228). Only, for example, the heater elements (228) are composed of a material having a positive TCR or negative TCR greater than 1.0%, such as molybdenum, nickel, tungsten, etc. The heater elements (228-1 and 228-2) may be individually controllable. For example, the heater elements (228) may receive power (e.g., current) in response to commands from a controller (232), which may correspond to the controller (182) of FIG. 1. In other examples, the substrate support (200) may correspond only to a single controllable zone and heater element. In some examples, the substrate support (200) may include a temperature sensor (236) located in the center (i.e., within the inner zone (224-1)). The controller (232) is configured to calculate the resistance of the heater elements (228-1 and 228-2) based on the measured current and voltages associated with the heater elements (228-1 and 228-2), and to calculate and control the respective temperatures within the zones (224-1 and 224-2) based on the calculated resistances as described in more detail below.

[0033] Measurement signals (240) representing the current and voltage of heater elements (228) are provided to the controller (232). For example, the measurement signals (240) may include raw voltage and current measurements. The controller (232) calculates the resistances (i.e., resistance values) of the heater elements (228) using the voltage and current measurements. A filter box (244) may filter noise from the measurement signals (240). For example, the filter box (244) may implement a linear filter configured to filter system noise (e.g., periodic or high-frequency noise) from the measurement signals (240). The controller (232) according to the present disclosure includes a filter module configured to selectively filter the calculated resistance values.

[0034] Referring to FIG. 3, an exemplary controller (300) configured to calculate and control temperatures within zones (224-1 and 224-2) is shown. The controller (300) receives signals, collectively referred to as signals (304), including but not limited to voltage signals (304-1) and current signals (304-2). The voltage signals (304-1) may include signals representing the respective voltages of the heater elements (228) of the zones (224). The current signals (304-2) may include signals representing the respective currents through the heater elements (228). For example, voltage signals (304-1) and current signals (304-2) may correspond to analog measurement signals provided from each sensor (308) through a filter box (244) (not shown in FIG. 3).

[0035] An analog-to-digital (A / D) converter (312) converts voltage signals (304-1) and current signals (304-2) into digital signals (316). Although illustrated as a single A / D converter (312), the controller (300) may implement different A / D converters for each of the signals (304). A resistance calculation module (320) is configured to calculate the resistance value of each of the heater elements (228) based on the digital signals (316). For example, the resistance calculation module (320) may calculate the resistances based on the voltages and currents expressed according to Ohm's law and may output signals (324) representing the calculated resistances. In some examples, the resistance calculation module (320) may correct the gain for the digital signals (316) and / or apply an offset before calculating the resistances. In some examples, the resistance calculation module (320) may calculate the power output of each of the heater elements (228) based on the voltages and currents shown (e.g., by multiplying the voltage and current for each of the heater elements (228)) and may output signals (328) representing the calculated power values.

[0036] A temperature calculation module (332) according to the present disclosure receives the calculated resistances for each of the heater elements (228) and calculates the temperature of each of the zones (224-1 and 224-2) based on the calculated resistances. For example, as described above, the material of the heater elements (228) has a known TCR that exhibits resistance changes in response to temperature changes. Accordingly, for a predetermined heater element (228) and material, the temperature calculation module (332) is configured to calculate the temperature changes of the corresponding zone (224) based on the changes in resistance.

[0037] For example, the temperature of zone (224) is T = TCR * R - TC The resistance of the heater element (228) may be correlated according to the curve / slope defined by (Equation 1), where T is the temperature of the zone (224), R is the calculated resistance of the heater element (228), TCR is the TCR modifier (e.g., °C / Ohm), and T C is the temperature constant offset (e.g., 230 ℃. For example, for molybdenum, the temperature of the heater element is T = (46 ℃ / Ohm) * R - 230 ℃ may also be calculated. The temperature calculation module (332) stores data indicating the correlation between the temperatures of the zones (224) and the resistances of the heater elements (228). In one example, the temperature calculation module (332) stores a resistance-to-temperature (R / T) conversion table that indexes possible ranges of the measured resistances of the heater elements (228) to the corresponding temperatures of the zones (224) (e.g., 1 ℃ intervals) according to the curve defined by Equation 1. In other examples, the temperature calculation module (332) may store and execute a model, formula, etc. to calculate the temperatures of the zones (224) based on the calculated resistances. The temperature calculation module (332) outputs the respective temperatures of the zones (224-1 and 224-2) based on the calculated resistances and the R / T conversion table.

[0038] The temperature calculation module (332) may generate an R / T conversion table during initial calibration (e.g., during fabrication, assembly, service, etc. of the processing chamber (108), during installation and / or service of the substrate support (200), etc.). For example, during calibration, the resistances of the heater elements (228) may be calculated while measuring temperatures within the zones (224) with one or more temporary temperature sensors (e.g., sensors on a temperature sensing test board placed on the substrate support (200).

[0039] A temperature calculation module (332) according to the present disclosure includes a filter module (334) configured to selectively filter calculated resistance values ​​and / or calculated temperatures. That is, as described below, the filter module (334) may selectively filter the calculated resistance values ​​before they are converted into calculated temperatures, or may filter the calculated temperatures after they are converted from the calculated resistance values. For exemplary purposes, the filter module (334) will be described as operating according to the calculated resistance values ​​before they are converted into calculated temperatures.

[0040] The temperature calculation module (332) is configured to selectively apply the filter module (334) to the calculated resistance values ​​(i.e., the signals (324)) in response to one or more conditions being met. That is, if one or more conditions are not met, the temperature calculation module (332) converts the calculated resistance values ​​represented by the signals (324) into temperatures as described above. Conversely, if one or more conditions are met, the filter module (334) filters the signals before converting them into calculated temperatures.

[0041] For example, the temperature calculation module (332) may receive one or more signals (340) representing each condition within the substrate processing system (100) that may affect resistance and temperature measurements. For example, the signals (340) may represent various operation parameters of the substrate processing system (100), such as whether the substrate is present on the substrate support (200), what process steps are performed, process parameters (e.g., process or purge gas flow, pressure changes, plasma activation, RF power changes, etc.), movement of components of the substrate support (200), etc. The temperature calculation module (332) may compare the information indicated by the signals (340) with stored data (e.g., a ruleset) to determine whether one or more conditions are satisfied.

[0042] The filter module (334) may implement linear filtering and / or non-linear filtering and may be configured to selectively apply offsets (i.e., resistance value offsets), median filtering, Kalman filtering, etc. to the signals (324). More specifically, the filter module (334) is configured to selectively filter the signals (324) based on a determination of whether a change in resistance values ​​represented by the signals (324) satisfies one or more conditions.

[0043] As described above, changes in resistance values ​​typically represent corresponding changes in temperature. However, system variations unrelated to temperature changes may also cause changes in calculated resistance values, such as variations caused by component wear, oxidation, loosening of fittings, connections, wiring, and splices, etc. These system variations may occur over the lifetime of the substrate support (200) and may increase in magnitude. Accordingly, the temperature calculation module (332) is configured to determine whether the resistance changes are caused by actual changes in temperature or by permanent or intermittent system variations. For example, the temperature calculation module (332) determines whether a resistance change is expected based on a comparison of the expected temperature change in a predetermined zone, the expected rate of temperature change, and the changes in temperatures of other zones and / or processing stations. The filter module (334) applies filtering to the resistance values ​​calculated based on the determination made by the temperature calculation module (332), as described in more detail below in FIG. 4.

[0044] The temperature control module (344) receives a signal (346) representing calculated temperatures and controls the heater elements (228) accordingly. That is, the signal (346) corresponds to one of (i) temperatures calculated using unfiltered signals (324) and (ii) temperatures calculated using signals (324) filtered by the filter module (334) as described above. The temperature control module (344) is configured to output power control signals (348) to adjust the power (e.g., current) supplied to the heater elements (228) based on the calculated temperatures. In this manner, the controller (300) is configured to implement closed-loop control of the temperatures of the zones (224).

[0045] The temperature control module (344) may be further configured to receive output signals (328) representing calculated power values ​​and to compare the commanded power and calculated power values ​​indicated by the power control signals (348). In some examples, the difference between the commanded power and the calculated power may represent one or more faults, including but not limited to wiring faults (e.g., disconnection or reverse wiring, wiring short, etc.). The controller (300) may be configured to indicate the fault to the user (e.g., via the user interface / display (352) of the controller (300).

[0046] Similarly, the temperature calculation module (332) may be configured to determine and / or indicate faults associated with the difference between the calculated temperatures and the temperatures sensed (e.g., from the temperature sensor (340)), the difference between the calculated temperatures of each of the zones (224) (e.g., a difference greater than a threshold value), the difference between the calculated temperatures and the target temperatures (e.g., as controlled via signals (348)). For example, these differences may further indicate other faults, such as wiring or damaged components of the substrate support (200).

[0047] Now, referring to FIG. 4, an exemplary method (400) for selectively filtering signals corresponding to resistances calculated in a substrate support according to the present disclosure is illustrated. For example, the method (400) is implemented at least partially by a temperature calculation module (332). In (404), the method (400) uses a filter module (334) to generate and store data (e.g., in the memory of the controller (300)) that defines one or more conditions for filtering signals (324). For example, the data may include a truth table that identifies one or more conditions for filtering signals (324). In one example, the conditions correspond to determining whether a resistance change is expected due to an expected temperature change, determining whether a rate of temperature change is expected (i.e., within a defined range), and determining whether other zones and / or processing stations experience similar temperature changes. The temperature calculation module (332) determines whether to filter the signals (324) according to the truth table.

[0048] In (408), method (400) (e.g., temperature calculation module (332)) receives one or more signals (e.g., signals (324)) representing the calculated resistance of a heater element during a predetermined sampling period. While the temperature calculation module (332) receives signals corresponding to multiple heater elements per sampling period, method (400) will be described for a single heater element. In (412), method (400) (e.g., temperature calculation module (332)) determines whether the calculated resistance represents a change in temperature. For example, the temperature calculation module (332) compares the calculated resistance to a previously calculated resistance (e.g., as calculated in a previous sampling period). If true, method (400) continues to (416). If false, method (400) continues to (408).

[0049] In (416), method (400) (e.g., temperature calculation module (332)) determines whether a temperature change for the corresponding heater element is expected. For example, a temperature change may be expected during various operations related to substrate processing, including but not limited to the transfer of the substrate to and from the substrate support (200), the initiation or interruption of various process steps (e.g., process or purge gas flow, pressure changes, plasma activation, RF power changes, etc.), the movement of components of the substrate support (200), etc. Method (400) determines whether a temperature change is expected based in part on signals (340) representing various operation parameters of the substrate processing system (100) as described above. If true, method (400) continues to (420). If false, method (400) continues to (424).

[0050] In (420), the method (400) (e.g., the temperature calculation module (332)) processes the signal (324) without additional filtering from the filter module (334). For example, the method (400) calculates the temperature of the heater element, provides the signal (346) to the temperature control module (344), and controls the temperature of the heater element accordingly. An exemplary method for controlling the temperature is described in more detail in U.S. Patent No. 10 / 633,742, granted April 28, 2020, whose entire contents are incorporated herein by reference.

[0051] In (424), method (400) (e.g., temperature calculation module (332)) determines whether the temperature change rate represented by the calculated resistance is expected. For example, the temperature calculation module (332) compares the temperature change rate with one or more threshold values ​​(e.g., threshold values ​​specified in the stored data). The threshold values ​​may correspond to the temperature rates of change limits associated with each application or processing step. The temperature rates of the change limits may be selected based on the maximum change rates expected during the processing step to be performed. If true, method (400) continues to (420). If false, method (400) continues to (428).

[0052] In (428), the method (400) (e.g., the temperature calculation module (332)) determines whether the temperature change (e.g., change in magnitude and / or rate of change) indicated by the calculated resistance is similar to the temperature changes calculated for other heater elements and / or processing stations. As noted above, the temperature calculation module (332) may receive signals (324) corresponding to multiple heater elements for different zones of the same substrate support (200) and may also receive signals (324) corresponding to heater elements of additional substrate supports in different processing chambers or stations. Accordingly, the method (400) determines whether other heater elements or substrate supports experience a change similar to the temperature change corresponding to the calculated resistance (e.g., a change in magnitude or a rate of change within a range such as within 10%). If true, the method (400) continues to (420). If false, method (400) continues to (432).

[0053] In (432), method (400) (e.g., temperature calculation module (332)) applies additional filtering to the signal (324). For example, the temperature calculation module (332) filters the signal (324) using a filter module (334). That is, if a temperature change is not expected, the rate of temperature change exceeds the limits associated with the process step to be performed, and the heater elements of other zones and / or substrate supports do not experience a similar temperature change, the temperature calculation module (332) may determine that the change in calculated resistance was not caused by an actual temperature change. Rather, the change in calculated resistance may be caused by system variations such as oxidation, component wear, loosening of fittings, connections, and splices, etc., as described above. Accordingly, the filter module (334) filters the signal (324) to compensate for system variations (e.g., by applying an offset), and method (400) continues to (436).

[0054] In (436), the method (400) (e.g., the temperature calculation module (332)) processes the signal (324) following additional filtering applied by the filter module (334). For example, the method (400) calculates the temperature of the heater element using the filtered signal (324), provides the signal (346) to the temperature control module (344), and controls the temperature of the heater element accordingly.

[0055] The foregoing description is by nature merely illustrative and is not intended to limit the present disclosure, its applications, or uses in any way. The extensive teachings of the present disclosure may be implemented in various forms. Accordingly, while the present disclosure includes specific examples, the true scope of the present disclosure should not be limited in this way, as other modifications will become apparent upon study of the drawings, the specification, and the claims below. It should be understood that one or more steps of the method may be performed in a different order (or simultaneously) without altering the principles of the present disclosure. Furthermore, although each of the embodiments has been described above as having specific features, any one or more of these features described for any embodiment of the present disclosure may be implemented with features of any other embodiments and / or in combination with features of any other embodiments, even if the combination is not explicitly described. That is, the described embodiments are not mutually exclusive, and substitutions of one or more embodiments with other embodiments remain within the scope of the present disclosure.

[0056] Spatial and functional relationships between elements (e.g., modules, circuit elements, semiconductor layers, etc.) are described using various terms including “connected,” “engaged,” “coupled,” “adjacent,” “next to,” “on top of,” “above,” “below,” and “disposed.” When a relationship between a first element and a second element is described in the disclosure above, unless explicitly described as “direct,” this relationship may be a direct relationship in which no other mediating elements exist between the first element and the second element, but may also be an indirect relationship in which one or more mediating elements exist (spatially or functionally) between the first element and the second element. As used in this specification, at least one of the phrases A, B, and C should be interpreted as meaning (A or B or C) logically using a non-exclusive logical OR, and should not be interpreted as meaning "at least one A, at least one B, and at least one C."

[0057] In some embodiments, the controller is part of a system that may be part of the examples described above. These systems may include semiconductor processing equipment comprising processing tools or tools, chambers or chambers, a platform or platforms for processing and / or specific processing components (wafer pedestals, gas flow systems, etc.). These systems may be integrated with electronics to control their operation before, during, and after the processing of a semiconductor wafer or substrate. The electronic device may be referred to as a "controller" that may control the systems or sub-parts of the systems or various components. The controller may be programmed to control any of the processes disclosed herein, including, depending on the processing requirements and / or type of the system, the delivery of processing gases, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, position and motion settings, and wafer transfer into and out of load locks connected to or interfacing with tools and other transfer tools and / or a specific system.

[0058] Generally speaking, a controller may be defined as an electronic device having various integrated circuits, logic, memory, and / or software that receives instructions, issues instructions, controls operations, enables cleaning operations, enables endpoint measurements, etc. Integrated circuits may include chips in the form of firmware that store program instructions, chips defined as digital signal processors (DSPs), application-specific integrated circuits (ASICs), and / or one or more microprocessors or microcontrollers that execute program instructions (e.g., software). Program instructions may be instructions that communicate with the controller or the system in the form of various individual settings (or program files) that define operation parameters for performing a specific process on or for a semiconductor wafer. In some embodiments, the operation parameters may be part of a recipe defined by process engineers to achieve one or more processing steps during the manufacture of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or wafer dies.

[0059] In some implementation examples, the controller may be integrated with the system, coupled to the system, otherwise networked to the system, or coupled to or part of a computer that may be a combination thereof. For example, the controller may be all or part of a fab host computer system capable of enabling remote access to wafer processing, or it may be located within the "cloud." The computer may enable remote access to the system to monitor the current progress of manufacturing operations, examine the history of past manufacturing operations, examine trends or performance measurements from multiple manufacturing operations, change parameters of the current processing, set processing steps following the current processing, or start a new process. In some examples, a remote computer (e.g., a server) may provide process recipes to the system over a network, which may include a local network or the Internet. The remote computer may include a user interface that enables the input or programming of parameters and / or settings to be subsequently transmitted from the remote computer to the system. In some examples, the controller receives instructions in the form of data that specify parameters for each of the processing steps to be performed during one or more operations. It should be understood that parameters may be specific to the type of tool configured to be controlled or interfaced by the controller and the type of process to be performed. Accordingly, as described above, the controller may be distributed by including one or more individual controllers that are networked and operate together toward a common purpose, such as the processes and controls described herein, for example. An example of a distributed controller for such purposes would be one or more integrated circuits on a chamber that communicate with one or more integrated circuits located remotely (e.g., at the platform level or as part of a remote computer) that are combined to control a process on the chamber.

[0060] Without limitation, exemplary systems may include a plasma etching chamber or module, a deposition chamber or module, a spin-rinse chamber or module, a metal plating chamber or module, a cleaning chamber or module, a bevel edge etching chamber or module, a physical vapor deposition (PVD) chamber or module, a chemical vapor deposition (CVD) chamber or module, an atomic layer deposition (ALD) chamber or module, an atomic layer etch (ALE) chamber or module, an ion implantation chamber or module, a track chamber or module, and any other semiconductor processing systems that may be used or associated in the manufacture and / or fabrication of semiconductor wafers.

[0061] As noted above, depending on the process steps or steps to be performed by the tool, the controller may communicate with one or more of other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout the factory, a main computer, another controller, or tools used in material transfer for moving containers of wafers from tool locations and / or load ports within the semiconductor manufacturing plant and to tool locations and / or load ports.

Claims

Claim 1 A controller for controlling the temperature of a substrate support in a substrate processing system, comprising: a resistance calculation module for calculating a first resistance of a first heater element among a plurality of heater elements of a first substrate support; a temperature calculation module for calculating a first temperature of the first heater element based on the calculated first resistance; and a filter module for filtering a first signal corresponding to the calculated first resistance, wherein the temperature calculation module causes the filter module to selectively filter the first signal in response to a determination of whether at least one condition associated with the operation of the substrate processing system is satisfied. Claim 2 In claim 1, the at least one condition is a controller for controlling the temperature of a substrate support, corresponding to the operation of the substrate processing system associated with the temperature change of the first heater element. Claim 3 A controller for controlling the temperature of a substrate support, wherein the temperature calculation module determines whether a temperature change of the first heater element is expected based on the calculated first resistance, and in response to the determination that the temperature change is not expected, causes the filter module to selectively filter the first signal. Claim 4 A controller for controlling the temperature of a substrate support, wherein the temperature calculation module determines whether the temperature change rate of the first heater element exceeds a threshold value based on the calculated first resistance, and in response to the determination that the temperature change rate exceeds the threshold value, causes the filter module to selectively filter the first signal. Claim 5 A controller for controlling the temperature of a substrate support, wherein the temperature calculation module compares a first temperature change of the first heater element with a second temperature change of the second heater element and, based on the comparison, causes the filter module to selectively filter the first signal. Claim 6 In claim 5, the second heater element is a controller for controlling the temperature of the substrate support, which is located within the second substrate support. Claim 7 In claim 1, the filter module is a controller for controlling the temperature of a substrate support, which applies a resistance offset to the first signal in response to the determination of whether at least one condition associated with the operation of the substrate processing system is satisfied. Claim 8 A controller for controlling the temperature of a substrate support, further comprising a temperature control module configured to control power provided to the first heater element based on the first signal in claim 1. Claim 9 A controller for controlling the temperature of a substrate support, wherein the resistance calculation module receives a first current corresponding to the first heater element, receives a first voltage corresponding to the first heater element, and calculates the first resistance based on the first voltage and the first current. Claim 10 In claim 9, the temperature calculation module is a controller for controlling the temperature of a substrate support, which calculates the first temperature based on the temperature coefficient of the calculated first resistance and the resistance of the first heater element. Claim 11 A system comprising: a resistance calculation module for receiving a current corresponding to a heater element within a substrate support, receiving a voltage corresponding to the heater element, and calculating the resistance of the heater element based on the voltage and the current; a temperature calculation module for calculating the temperature of the heater element based on the calculated resistance; a filter module for filtering a signal corresponding to the calculated resistance, wherein the temperature calculation module causes the filter module to selectively filter the signal in response to a determination of whether at least one condition associated with a change in the temperature of the heater element is satisfied; and a temperature control module configured to control the power supplied to the heater element based on the signal when filtered by the filter module. Claim 12 In claim 11, the temperature calculation module determines at least one of (i) whether a change in the temperature of the heater element is expected and (ii) whether the rate of change in the temperature of the heater element exceeds a threshold value, based on the calculated first resistance. Claim 13 A system according to claim 11, wherein the temperature calculation module causes the filter module to selectively filter the signal in response to a determination that a change in the temperature of the heater element is not expected, a determination that the rate of change in the temperature of the heater element exceeds a threshold value, and a determination that the change in the temperature of the heater element is not within the range of a change in the temperature of another heater element. Claim 14 A method for controlling the temperature of a substrate support in a substrate processing system, comprising: a step of calculating a first resistance of a first heater element of a plurality of heater elements of a first substrate support; a step of calculating a first temperature of the first heater element based on the calculated first resistance; and a step of selectively filtering a first signal corresponding to the calculated first resistance in response to a determination of whether at least one condition associated with the operation of the substrate processing system is satisfied. Claim 15 A method for controlling the temperature of a substrate support, wherein at least one condition corresponds to the operation of the substrate processing system associated with the temperature change of the first heater element. Claim 16 A method for controlling the temperature of a substrate support according to claim 14, further comprising the steps of determining whether a temperature change of the first heater element is expected based on the calculated first resistance, and selectively filtering the first signal in response to the determination that the temperature change is not expected. Claim 17 A method for controlling the temperature of a substrate support according to claim 14, further comprising the steps of determining whether the temperature change rate of the first heater element exceeds a threshold value based on the calculated first resistance, and selectively filtering the first signal in response to the determination that the temperature change rate exceeds the threshold value. Claim 18 A method for controlling the temperature of a substrate support according to claim 14, further comprising the step of comparing a first temperature change of the first heater element with a second temperature change of the second heater element and the step of selectively filtering the first signal based on the comparison. Claim 19 A method for controlling the temperature of a substrate support, wherein the second heater element is located within the second substrate support. Claim 20 A method for controlling the temperature of a substrate support, further comprising the step of controlling power provided to the first heater element based on the first signal in claim 14.

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