TWI868119B - Substrate processing system and method of controlling substrate support temperature - Google Patents

Abstract

A substrate processing system includes: a substrate support within a processing chamber to vertically support a substrate; a temperature probe including: a first temperature sensor to measure a first temperature of the substrate support; a second temperature sensor to measure a second temperature of the substrate support; a third temperature sensor to measure a third temperature of the substrate support; and a fourth temperature sensor to measure a fourth temperature of the substrate support; a temperature module to: in a first state, determine a substrate support temperature of the substrate support based on the first, second, third, and fourth temperatures; in a second state, determine the substrate support temperature based on only three of the first, second, third, and fourth temperatures; and a temperature control module configured to control at least one of heating and cooling of the substrate support based on the substrate support temperature.

Description

Substrate processing system and substrate support temperature control method

The present disclosure relates to a temperature probe for a base plate of a substrate support of a substrate processing system, and more particularly to debugging and utilizing measurements of a temperature sensor of the temperature probe.

The background description provided here is for the purpose of generally presenting the context of the present disclosure. The works of the inventors currently named, to the extent described in this prior art section, and embodiments that may not otherwise qualify as prior art at the time of application, are not admitted, either expressly or impliedly, as prior art to the present disclosure.

A substrate processing system may be used to process a substrate, such as a semiconductor wafer. Exemplary processes that may be performed on a substrate include, but are not limited to, chemical vapor deposition (CVD), atomic layer deposition (ALD), conductor etching, and/or other etching, deposition, or cleaning processes. In a processing chamber of a substrate processing system, a substrate may be disposed on a substrate support, such as a pedestal, an electrostatic chuck (ESC), etc. During etching, a gas mixture may be introduced into the processing chamber, and a plasma may be used to initiate a chemical reaction.

In one feature, a substrate processing system includes: a substrate support in a processing chamber for vertically supporting a substrate; a temperature probe including: a first temperature sensor for measuring a first temperature of the substrate support; a second temperature sensor for measuring a second temperature of the substrate support; a third temperature sensor for measuring a third temperature of the substrate support; and a fourth temperature sensor for measuring a fourth temperature of the substrate support. four temperatures; a temperature module for: in a first state, determining a substrate support temperature of the substrate support based on all of the first, second, third, and fourth temperatures; in a second state, determining the substrate support temperature of the substrate support based on only three of the first, second, third, and fourth temperatures; and a temperature control module, constructed to control at least one of heating and cooling of the substrate support based on the substrate support temperature.

In a further feature, the temperature module sets the substrate support temperature based on an average of at least three of the first, second, third, and fourth temperatures.

In a further feature, the substrate support includes: an upper portion for vertically supporting the substrate; and a bottom plate for vertically supporting the upper portion; the first temperature sensor is used to measure the first temperature of the bottom plate; the second temperature sensor is used to measure the second temperature of the substrate support; the third temperature sensor is used to measure the third temperature of the substrate support; and the fourth temperature sensor is used to measure the fourth temperature of the substrate support.

In a further feature, the substrate support includes: an upper portion for vertically supporting the substrate; and a bottom plate for vertically supporting the upper portion; the first temperature sensor is used to measure the first temperature of the upper portion; the second temperature sensor is used to measure the second temperature of the upper portion; the third temperature sensor is used to measure the third temperature of the upper portion; and the fourth temperature sensor is used to measure the fourth temperature of the upper portion.

In a further feature, the temperature module is used to determine the substrate support temperature based on at least three of the following: a first average of X of the first temperatures, where X is an integer greater than one; a second average of X of the second temperatures; a third average of X of the third temperatures; and a fourth average of X of the fourth temperatures.

In a further feature, the temperature module is used to determine the substrate support temperature based on an average of at least three of the first average value, the second average value, the third average value, and the fourth average value.

In a further feature, when a first difference between a maximum of the first average, the second average, the third average, and the fourth average and a minimum of the first average, the second average, the third average, and the fourth average is less than a temperature, the temperature module determines the substrate support temperature based on all of the first average, the second average, the third average, and the fourth average.

In a further feature, when the first difference is greater than the substrate support temperature, the temperature module selectively determines the substrate support temperature based on three of the first, second, third, and fourth average values.

In a further feature, when a second difference between a second maximum of the first average, the second average, and the third average and a second minimum of the first average, the second average, and the third average is less than the substrate support temperature, the temperature module determines the substrate support temperature based on the first, second, and third averages and not based on the fourth average.

In a further feature, when a third difference between a third maximum of the first average, the second average, and the fourth average and a third minimum of the first average, the second average, and the fourth average is less than the substrate support temperature, the temperature module determines the substrate support temperature based on the first, second, and fourth averages and not based on the third average.

In a further feature, when a fourth difference between a fourth maximum of the first average, the third average, and the fourth average and a fourth minimum of the first average, the third average, and the fourth average is less than the substrate support temperature, the temperature module determines the substrate support temperature based on the first, third, and fourth averages and not based on the second average.

In a further feature, when a fifth difference between a fifth maximum of the second average, the third average, and the fourth average and a fifth minimum of the second average, the third average, and the fourth average is less than the substrate support temperature, the temperature module determines the substrate support temperature based on the second, third, and fourth averages and not based on the first average.

In further features, when the first, second, third, fourth, and fifth differences are greater than the substrate support temperature, a debugging module indicates that a fault exists in the temperature probe.

In a further feature, when the fault exists in the temperature probe, the debugging module displays an alarm on a display.

In a further feature, the first, second, third, and fourth temperature sensors are solid-state temperature sensors.

In a further feature, a thermally conductive material is sandwiched between the substrate support and the first, second, third, and fourth temperature sensors.

In further features, a statistical module is used to: determine a first average value of multiple values of the first temperature; determine a second average value of multiple values of the first average value; determine a first standard deviation of the multiple values of the first average value; determine a second standard deviation of multiple time stamps associated with the multiple values of the first average value; determine a correlation coefficient based on the multiple time stamps and the multiple values of the first average value; determine a slope based on the correlation coefficient, the first standard deviation, and the second standard deviation; and a detection module is used to diagnose whether the slope is within a slope range.

In further features, the statistical module determines the correlation coefficient based on (a) the covariance of the plurality of values of the first mean and the plurality of time stamps, (b) the first standard deviation, and (c) the second standard deviation.

In a further feature, the statistical module sets the slope based on the correlation coefficient multiplied by the first standard deviation divided by the second standard deviation.

In further features, the temperature control module is configured to perform at least one of: selectively apply power to a thermal control element (TCE) based on the substrate support temperature; and selectively adjust coolant flow through a coolant channel in the substrate support based on the substrate support temperature.

In one feature, a substrate processing system includes: a substrate support in a processing chamber for vertically supporting a substrate; a temperature probe including: N temperature sensors for measuring N temperatures of the substrate support, wherein N is an integer greater than 3; a temperature module for: in a first state, determining a substrate support temperature of the substrate support based on all of the N temperatures; in a second state, determining the substrate support temperature of the substrate support based on a subset of the N temperatures; and a temperature control module for controlling at least one of heating and cooling of the substrate support based on the substrate support temperature. In various embodiments, the subset is only N-1 of the N temperatures.

In one feature, a method includes: measuring a first temperature of a substrate support that vertically supports a substrate during substrate processing by a first temperature sensor of a temperature probe; measuring a second temperature of the substrate support by a second temperature sensor of the temperature probe; measuring a third temperature of the substrate support by a third temperature sensor of the temperature probe; measuring a fourth temperature of the substrate support by a fourth temperature sensor of the temperature probe; in a first state, determining a substrate support temperature of the substrate support based on all of the first, second, third, and fourth temperatures; in a second state, determining the substrate support temperature of the substrate support based on only three of the first, second, third, and fourth temperatures; and controlling at least one of heating and cooling of the substrate support based on the substrate support temperature.

In a further feature, the step of determining the substrate support temperature includes: setting the substrate support temperature based on an average of at least three of the first, second, third, and fourth temperatures.

In a further feature, the substrate support includes: an upper portion for vertically supporting the substrate; and a bottom plate for vertically supporting the upper portion; the step of measuring the first temperature includes measuring the first temperature of the bottom plate; the step of measuring the second temperature includes measuring the second temperature of the substrate support; the step of measuring the third temperature includes measuring the third temperature of the substrate support; and the step of measuring the fourth temperature includes measuring the fourth temperature of the substrate support.

In a further feature, the substrate support includes: an upper portion for vertically supporting the substrate; and a bottom plate for vertically supporting the upper portion; the step of measuring the first temperature includes measuring the first temperature of the upper portion; the step of measuring the second temperature includes measuring the second temperature of the upper portion; the step of measuring the third temperature includes measuring the third temperature of the upper portion; and the step of measuring the fourth temperature includes measuring the fourth temperature of the upper portion.

In a further feature, the step of determining the substrate support temperature includes determining the substrate support temperature based on at least three of: a first average of X of the first temperatures, where X is an integer greater than one; a second average of X of the second temperatures; a third average of X of the third temperatures; and a fourth average of X of the fourth temperatures.

In a further feature, the step of determining the substrate support temperature includes: determining the substrate support temperature based on an average of at least three of the first average value, the second average value, the third average value, and the fourth average value.

In a further feature, the step of determining the substrate support temperature includes: determining the substrate support temperature based on all of the first, second, third, and fourth averages when a first difference between a maximum of the first, second, third, and fourth averages and a minimum of the first, second, third, and fourth averages is less than a temperature.

In a further feature, the step of determining the substrate support temperature includes: when the first difference is greater than the substrate support temperature, determining the substrate support temperature based on three of the first, second, third, and fourth average values.

In a further feature, the step of determining the substrate support temperature includes: determining the substrate support temperature based on the first, second, and third average values and not based on the fourth average value when a second difference between a second maximum value of the first, second, and third average values and a second minimum value of the first, second, and third average values is less than the substrate support temperature.

In a further feature, the step of determining the substrate support temperature includes: determining the substrate support temperature based on the first, second, and fourth average values and not based on the third average value when a third difference between a third maximum value among the first, second, and fourth average values and a third minimum value among the first, second, and fourth average values is less than the substrate support temperature.

In a further feature, the step of determining the substrate support temperature includes: determining the substrate support temperature based on the first, third, and fourth average values and not based on the second average value when a fourth difference between a fourth maximum value among the first, third, and fourth average values and a fourth minimum value among the first, third, and fourth average values is less than the substrate support temperature.

In a further feature, the step of determining the substrate support temperature includes: determining the substrate support temperature based on the second, third, and fourth average values and not based on the first average value when a fifth difference between a fifth maximum value among the second, third, and fourth average values and a fifth minimum value among the second, third, and fourth average values is less than the substrate support temperature.

In a further feature, the method further comprises: indicating that a fault exists in the temperature probe when the first, second, third, fourth, and fifth differences are greater than the substrate support temperature.

In a further feature, the method further comprises: displaying an alarm on a display when the fault exists in the temperature probe.

In a further feature, the first, second, third, and fourth temperature sensors are solid-state temperature sensors.

In a further feature, a thermally conductive material is sandwiched between the substrate support and the first, second, third, and fourth temperature sensors.

In further features, the method further comprises: determining a first average of the plurality of values of the first temperature; determining a second average of the plurality of values of the first average; determining a first standard deviation of the plurality of values of the first average; determining a second standard deviation of a plurality of time stamps associated with the plurality of values of the first average; determining a correlation coefficient based on the plurality of time stamps and the plurality of values of the first average; determining a slope based on the correlation coefficient, the first standard deviation, and the second standard deviation; and diagnosing whether the slope is within a slope range.

In a further feature, the step of determining the correlation coefficient includes determining the correlation coefficient based on (a) the covariance of the plurality of values of the first mean and the plurality of time stamps, (b) the first standard deviation, and (c) the second standard deviation.

In a further feature, the step of determining the slope comprises: setting the slope based on the correlation coefficient multiplied by the first standard deviation divided by the second standard deviation.

In further features, the step of controlling at least one of heating and cooling of the substrate support includes at least one of: selectively applying power to a thermal control element (TCE) based on the substrate support temperature; and selectively adjusting coolant flow through a coolant channel in the substrate support based on the substrate support temperature.

Other application areas of the present disclosure will become apparent from the implementation sections, patent application scope, and drawings. The implementation sections and specific examples are intended for illustrative purposes only and are not intended to limit the scope of the present disclosure.

100: Substrate processing system

102: Processing chamber

104: Upper electrode

106: Substrate support

108: Substrate

109: Shower head

110: Base plate

112: Ceramic layer

114: Layer

116: Coolant channel

120:RF generation system

122:RF voltage generator

124:Matching and allocating networks

130: Gas delivery system

132-1, 132-2, 132-N: Gas source

134-1, 134-2, 134-N: Valve

136-1, 136-2, 136-N: Mass flow controller

140: Manifold

142: Temperature control module

144: Thermal Control Element (TCE)

146: Coolant assembly

150: Valve

152: Pump

160: System control module

170:Robot

172: Load lock chamber

176: Seals

180:Edge ring

184: User interface device

204: Temperature sensor (temperature probe)

208: Circuit board

212: Groove

216: Temperature probe

304: Thermal conductor

306: Bottom surface

308: Temperature sensor

404: Myopia

406: Circuit board

408: Fasteners

412: Conductor

504: Pulse

508: Buffer module

512: Bottom plate temperature module

516: Substrate temperature module

524: Statistics module

526: Display

528: Debug module

The content of this disclosure will be more fully understood from the implementation method section and the accompanying drawings.

FIG1 is a functional block diagram of an exemplary substrate processing chamber.

FIG2 is a cross-sectional view of a portion of an example substrate support.

Figure 3 is a cross-sectional view of a portion of the substrate support, the temperature probe, and the thermal conductor.

FIG. 4 includes a perspective view of an example implementation of a circuit board and a temperature probe, and a close-up view of a portion of the circuit board and the temperature probe.

Figure 5 is a functional block diagram of an example debugging and control system.

Figures 6-9 include a flow chart describing an exemplary method for determining a baseplate temperature and managing the use of first, second, third, and fourth temperatures from a temperature sensor of a temperature probe.

In the drawings, reference symbols may be reused to identify similar and/or identical elements.

A substrate support, such as an electrostatic chuck, supports a substrate in a substrate processing chamber. A substrate is disposed on a ceramic portion of the substrate support during processing. A plurality of thermal control elements may be embedded in the substrate support. The thermal control elements may be controlled to at least one of heat and cool the substrate support. The substrate support includes a base plate. The base plate may be used as a heat sink for the thermal control elements. A coolant may be pumped through coolant channels in the base plate to cool the substrate support.

A single temperature sensor may measure the temperature of a substrate support, such as the temperature of a base plate. However, if that single temperature sensor fails, substrate processing may be interrupted while the single temperature sensor (and possibly one or more other components integrated with the single temperature sensor) is replaced or the failure is otherwise remedied.

This application relates to a temperature probe comprising N different temperature sensors for measuring N temperatures at a location on a substrate support. N is an integer greater than 3. The use of N temperature sensors provides redundancy and enables substrate processing to continue in the event that one of the N temperature sensors fails or loses connection, for example.

When the N temperatures are within a first range of each other, the N temperatures can be used to determine the temperature of the substrate support. The N temperature sensors may not be calibrated after installation. The measurement accuracy of the temperature sensor can be confirmed by the N temperatures being within a first range of each other.

When at least one of the N temperatures is outside the first range, N-1 of the temperatures within the range between each other are used to determine the temperature of the substrate support. The measurement accuracy of those temperature sensors can be confirmed by the N-1 temperatures within the range between each other.

If no combination of N-1 temperatures are within range of each other, a fault is detected in the temperature probe. When the temperature variation of the substrate support is less than the maximum variation, a transition from using N temperatures to using N-1 temperatures can be performed. Since these temperatures are used to control the temperature of the substrate support, this prevents the temperature of the substrate support from varying by more than an allowable amount.

Referring now to FIG. 1 , an exemplary substrate processing system 100 is shown. By way of example only, the substrate processing system 100 may be used to perform etching using a radio frequency (RF) plasma.

The substrate processing system 100 includes a processing chamber 102 that encloses other components of the substrate processing system 100 and contains an RF plasma. The processing chamber 102 includes an upper electrode 104 and a substrate support 106, such as an electrostatic chuck (ESC).

During operation, the substrate 108 is disposed on the substrate support 106. An example of the substrate processing system 100 and the processing chamber 102 is shown. However, the present application is also applicable to other types of substrate processing systems and processing chambers, such as substrate processing systems that generate plasma in situ, substrate processing systems that achieve remote plasma generation and delivery (e.g., using plasma tubes, microwave tubes), etc.

The upper electrode 104 may include a gas distribution device, such as a showerhead 109, which introduces and distributes process gases within the processing chamber 102. The showerhead 109 may include a rod including one end connected to the top surface of the processing chamber 102. The base of the showerhead 109 is generally cylindrical and extends radially outward from an opposite end of the rod at a position spaced from the top surface of the processing chamber 102. A substrate-facing surface (or faceplate) of the base of the showerhead 109 includes a plurality of holes through which process gases or purge gases flow. Alternatively, the upper electrode 104 may include a guide plate and the process gas may be introduced in another manner.

The substrate support 106 includes a conductive bottom plate 110 that serves as a lower electrode. The bottom plate 110 supports a ceramic layer 112. One or more other layers 114 may be disposed between the ceramic layer 112 and the bottom plate 110.

The base plate 110 may include one or more coolant channels 116 for flowing coolant through the base plate 110. In some examples, a protective seal 176 may be provided.

An RF generation system 120 generates and outputs an RF voltage to one of the upper electrode 104 and the lower electrode (e.g., the bottom plate 110 of the substrate support 106) to ignite and maintain plasma in the processing chamber 102. The other of the upper electrode 104 and the bottom plate 110 can be direct current (DC) grounded, alternating current (AC) grounded, or floating. By way of example only, the RF generation system 120 can include an RF voltage generator 122 that generates an RF voltage that is fed to the upper electrode 104 or the bottom plate 110 by a matching and distribution network 124.

A gas delivery system 130 includes one or more gas sources 132-1, 132-2, ... and 132-N (collectively referred to as gas sources 132), where N is an integer greater than zero. The gas source 132 supplies one or more etching gases, carrier gases, inert gases, precursor gases, and mixtures thereof. The gas source 132 may also supply purge gases and other types of gases.

The gas source 132 is connected to a manifold 140 via valves 134-1, 134-2, ... and 134-N (collectively referred to as valves 134) and mass flow controllers 136-1, 136-2, ... and 136-N (collectively referred to as mass flow controllers). The output of the manifold 140 is fed to the processing chamber 102. By way of example only, the output of the manifold 140 is fed to the showerhead 109 and output from the showerhead 109 to the processing chamber 102.

The temperature control module 142 is connected to an array of heating elements within the substrate support 106, such as a thermal control element (TCE) 144 disposed in the ceramic layer 112. For example, the TCE 144 may include, but is not limited to, macroscopic heating elements corresponding to each zone in a multi-zone heating plate and/or an array of microscopic heating elements disposed across multiple zones of a multi-zone heating plate. The TCE 144 may be, for example, a resistive heater that generates heat when power is applied to each heater, or may be another suitable type of heating element.

The temperature control module 142 controls the power supply to the TCE 144 to control the temperature of various locations on the substrate support 106 and the substrate 108. For example, the temperature control module 142 can control corresponding switches to connect and disconnect the TCE 144 to the power.

The temperature control module 142 can be in communication with the coolant assembly 146 to control the flow of coolant through the coolant channels 116 in the base plate 110. For example, the coolant assembly 146 can include a coolant pump, a storage tank, and one or more heat exchangers. The temperature control module 142 operates the coolant assembly 146 (e.g., the coolant pump) to selectively flow coolant through the coolant channels 116 to cool the substrate support 106. The temperature control module 142 can also control the speed of the coolant pump to control the flow rate of the coolant through the coolant channels 116. The temperature control module 142 can work with the coolant assembly 146 to control the TCE 144, for example, to achieve one or more target temperatures.

The valve 150 and pump 152 may be used to exhaust reactants from the processing chamber 102. The system control module 160 may control the components of the substrate processing system 100. Although shown as a separate controller, the temperature control module 142 may be implemented within the system control module 160.

The robot 170 may transfer substrates to and from the substrate support 106. For example, the robot 170 may transfer substrates between the substrate support 106 and the load lock chamber 172.

In some examples, the substrate support 106 includes an edge ring 180. The edge ring 180 can be movable relative to the substrate 108 (e.g., movable upward and downward in a vertical direction). For example, the movement of the edge ring 180 can be controlled by one or more actuators in response to input from the system control module 160. In some examples, a user can input control parameters to the system control module 160 via one or more user interface devices 184, which can include one or more input and/or output devices (e.g., keyboard, mouse, touch screen), display, etc.

2 includes a cross-sectional view of a portion of an example implementation of a substrate support 106. A TCE 144 may be embedded in a ceramic layer 112. A plurality of temperature sensors (or temperature probes) 204 may also be embedded in the ceramic layer 112. Such temperature sensors 204 may be spaced apart from each other of such temperature sensors 204, or may be grouped into one or more other adjacent temperature sensors 204. In various implementations, the ceramic layer 112 may include one or more temperature sensors for each TCE. The temperature sensors 204 may be positioned respectively near (e.g., within a predetermined distance of) the TCE 144. For example, the temperature sensors 204 may be positioned respectively between each TCE 144 and the base plate 110. The temperature sensors 204 measure the temperature at their respective locations.

The TCE 144 is controlled by the temperature control module 142. The temperature control module 142 can individually control the application of power to the TCE 144. For example, switches can be connected in series with the TCE 144, respectively, and the temperature control module 142 can control the switches to control the power supply to the TCE 144, respectively. In various embodiments, the temperature control module 142 can control the application of power to a group of two or more of the TCEs 144. For example, switches can be connected in series with a group of two or more of the TCEs 144, and the temperature control module 142 can control the switches to control the power supply to the groups, respectively. The base plate 110 can be a single piece or include multiple parts.

The temperature control module 142 can be implemented on a circuit board 208, which is fixed in a groove 212 in the lower surface of the base plate 110. A temperature probe 216 can also be implemented on the circuit board 406, such as shown in FIG. 4. The temperature probe 216 includes a temperature sensor for measuring the temperature of the base plate 110 respectively.

The temperature control module 142 receives the temperature measured by the temperature sensor 204 and the temperature measured by the temperature probe 216. The temperature control module 142 controls at least one of the coolant assembly 146 and the TCE 144 based on at least one of (i) the temperature measured by the temperature sensor 204 and (ii) the temperature measured by the temperature probe 216. For example, the temperature control module 142 may control one or more of the TCEs 144 to adjust the temperature measured by one of the temperature sensors 204 associated with the corresponding TCE 144 toward a target temperature. As another example, the temperature control module 142 can control the coolant assembly 146 to control the flow rate of the coolant through the coolant channel 116 based on one or more temperatures measured by the temperature probe 216.

FIG. 3 is a cross-sectional view including a portion of a substrate support 106 (e.g., base plate 110), a temperature probe 216, and a thermal conductor 304. The thermal conductor 304 can be made of a thermally conductive material (e.g., a slurry) and can be sandwiched between the temperature probe 216 and a bottom surface 306 of the base plate 110. An example temperature sensor 308 of the temperature probe 216 is depicted. The temperature sensor 308 of the temperature probe 216 can contact the thermal conductor 304. The thermal conductor 304 can be configured to transfer heat equally so that each temperature sensor 308 should measure the same temperature within a predetermined tolerance. The temperature sensor 308 can be, for example, a solid state temperature sensor. The accuracy of the temperature sensor 308 can be, for example, +/- 0.5 degrees Celsius or less. In various embodiments, the thermal conductor 304 may be omitted and the temperature sensor 308 may directly contact the bottom surface 306 of the base plate 110.

FIG. 4 is a perspective view of an example implementation of a circuit board 406 and a temperature probe 216 taken from a side of the circuit board 406 that faces the bottom surface 306 of the base plate 110. FIG. 4 also includes a close-up view 404 of a portion of the circuit board 406 and the temperature probe 216.

In various embodiments, the temperature sensors 308 may be arranged in two rows and two columns, with each temperature sensor 308 being located in a row and a column. However, the temperature sensors 308 may be positioned and arranged differently. As shown, the temperature probe 216 may include four temperature sensors 308. More generally, the temperature probe 216 includes N temperature sensors, where N is an integer greater than three.

The temperature probe 216 can be secured to the circuit board 208, for example using one or more fasteners 408 or in another suitable manner. The temperature probe 216 includes conductors 412 that are electrically connected to the temperature sensors 308, respectively. Electrical conductors (e.g., traces and/or leads) electrically connect the conductors 412 to the temperature control module 142 to transmit the temperature measured by the temperature sensor 308 to the temperature control module 142.

FIG5 is a functional block diagram of an example debugging and control system. Clock 504 selectively generates time stamps during substrate processing. Clock 504 may generate time stamps at a clock frequency, such as 20 Hz or another suitable frequency. Thus, clock 504 generates a time stamp every cycle equal to 1 divided by the clock frequency.

A buffer module 508 is electrically connected to each temperature sensor 308 of the temperature probe 216. The buffer module 508 receives a first temperature (TA) measured by a first one of the temperature sensors 308, a second temperature (TB) measured by a second one of the temperature sensors 308, a third temperature (TC) measured by a third one of the temperature sensors 308, and a fourth temperature (TD) measured by a fourth one of the temperature sensors 308. The buffer module 508 stores the first, second, third, and fourth temperatures each time a timestamp is generated. The buffer module 508 also stores the timestamp.

The buffer module 508 stores at least a number (X) of groups of temperatures and time stamps. The number (X) may be calibrated and may be set to, for example, 20 or another suitable integer. The stored values are used to generate statistical values, as discussed further below. For those of the temperature sensors 308 that are lost or determined to be providing invalid temperatures, the buffer module 508 may store a temperature value of zero (0) Kelvin. Although examples of temperatures measured in Kelvin are provided, other suitable temperature units may be used.

During substrate processing, the baseplate temperature module 512 determines the temperature of the baseplate 110 based on three or more of the first, second, third, and fourth temperatures. The temperature of the baseplate 110 will be referred to as the baseplate temperature. For example, the baseplate temperature module 512 may set the baseplate temperature based on or equal to an average of the three or more temperatures. The baseplate temperature module 512 may determine which three or more temperatures are used to determine the baseplate temperature, as discussed further below.

During substrate processing, the substrate temperature module 516 determines the temperature of the substrate 108 on the substrate support 106 based on the baseplate temperature. The substrate temperature module 516 may further determine the temperature of the substrate 108 based on one or more other operating parameters, such as one or more temperatures measured by one or more temperature sensors 204. The substrate temperature module 516 may determine the temperature of the substrate 108, for example, using one or more equations and/or lookup tables that relate the baseplate temperature and other operating parameters to the substrate temperature.

During substrate processing, the temperature control module 142 controls at least one of heating and cooling of the substrate support 106 based on the substrate temperature. For example, the temperature control module 142 can adjust the flow rate of coolant through the coolant channel 116 via the coolant assembly 146 based on the substrate temperature. The temperature control module 142 can adjust the flow rate, for example, to adjust the substrate temperature toward or to a target temperature. Additionally or alternatively, the temperature control module 142 can control one or more of the TCEs 144 based on the substrate temperature. For example, the temperature control module 142 can control one or more of the TCEs 144 to adjust the substrate temperature toward or to a target temperature.

The statistics module 524 determines various statistics during substrate processing based on the temperature and other parameters stored by the buffer module 508, as discussed further below. As discussed further below, the debugging module 528 diagnoses whether a fault exists in the temperature probe 216 based on one or more statistics.

When a fault exists in the temperature probe 216, the debug module 528 can take one or more actions. For example, the debug module 528 can display a predetermined message associated with the fault in the temperature probe 216 on the display 526. Additionally or alternatively, when a fault occurs in the temperature probe 216, the debug module 528 can cause the system control module 160 to stop substrate processing. For example, the debug module 528 can cause the system control module 160 to actuate the gas delivery system 130 (e.g., close the valve 134) and stop the flow of one or more gases to the processing chamber 102. Additionally or alternatively, the debug module 528 may cause the system control module 160 to adjust the RF generation system 120 to stop applying power to one, more than one, or all components within the processing chamber 102. In response to receiving user input to acknowledge the presence of a fault and clear the fault, the debug module 528 may clear the fault and allow substrate processing to proceed.

The debugging module 528 also sets a first signal and a second signal based on the statistical value during substrate processing. The first signal can be, for example, a first flag (e.g., flag A) or another suitable type of signal. The second signal can be, for example, a second flag (e.g., flag B) or another suitable type of signal. The state of the first signal indicates how many temperature sensors 308 are used to determine the baseplate temperature. The state of the second signal indicates to the baseplate temperature module 512 which of the temperature sensors 308 the stored temperature is used to determine the baseplate temperature. The setting of the state of the first and second signals is discussed further below.

In general, when all four temperature sensors 308 are within the first temperature range, the baseplate temperature module 512 determines the baseplate temperature based on the stored first, second, third, and fourth temperatures. The first temperature range can be calibrated and can be, for example, approximately 1 degree Celsius or another suitable range. When not all four temperature sensors 308 are within the first temperature range, the debug module 528 determines which three of the four temperature sensors 308 are within the temperature range. If three of the four temperature sensors 308 are within the temperature range, the debug module 528 determines whether the three of the four temperature sensors 308 are within the second temperature of the previous (e.g., last) baseplate temperature. The baseplate temperature module 512 determines the baseplate temperature based on the three of the four temperature sensors 308. This allows the baseplate temperature to be determined using three of the four temperature sensors 308 when switching to use the three of the four temperature sensors 308 does not result in a change in the baseplate temperature measurement beyond the second temperature and the three of the four temperature sensors 308 are within the first temperature range. This can achieve the desired accuracy. The second temperature can be calibrated or input to a certain scale and can be, for example, approximately 0.5 degrees Celsius, 0.25 degrees Celsius, or another suitable temperature.

When no combination of three of the four temperature sensors 308 is within the second temperature of the previous baseplate temperature, the debug module 528 disables the baseplate temperature module 512, diagnoses a fault in the temperature probe 216, and may take one or more actions. The operation of disabling the baseplate temperature module 512 disables the determination of the substrate temperature. When the fault in the temperature probe 216 is cleared, the debug module 528 re-enables the baseplate temperature module 512.

6-9 include a flow chart describing an exemplary method for determining a baseplate temperature and managing the use of a first, second, third, and fourth temperature from a temperature sensor 308. Control begins at 604 when a clock 504 generates a timestamp. Buffer module 508 stores the timestamp at 604. At 608, buffer module 508 stores samples of a first temperature (TA), and statistics module 524 determines a first average of the number (e.g., 20) of most recently stored values of the first temperature (TA). Statistics module 524 may set the first average based on or equal to the sum of the number (e.g., 20) of most recently stored values of the first temperature divided by the number (e.g., 20). Buffer module 508 stores the first average.

At 612, the buffer module 508 stores samples of the second temperature (TB), and the statistics module 524 determines a second average of the most recently stored values of the number (e.g., 20) of the second temperature (TB). The statistics module 524 may set the second average based on or equal to the sum of the most recently stored values of the number (e.g., 20) of the second temperature divided by the number (e.g., 20). The buffer module 508 stores the second average.

At 616, the buffer module 508 stores samples of the third temperature (TC), and the statistical module 524 determines a third average of the number (e.g., 20) of the most recently stored values of the third temperature (TC). The statistical module 524 may set the third average based on or equal to the sum of the most recently stored values of the number (e.g., 20) of the third temperature divided by the number (e.g., 20). The buffer module 508 stores the third average.

At 620, the buffer module 508 stores samples of the fourth temperature (TD), and the statistical module 524 determines a fourth average of the number (e.g., 20) of most recently stored values of the fourth temperature (TD). The statistical module 524 may set the fourth average based on or equal to the sum of the most recently stored values of the number (e.g., 20) of the fourth temperature divided by the number (e.g., 20). The buffer module 508 stores the fourth average.

其中CorrA是第一相關係數，Cov(x,y)是第一平均值(y)的最近儲存數值與最近儲存的時間戳記(x)的共變異數，σ_y是第一平均值(y)的最近儲存數值的標準差，而σ_x是最近儲存的時間戳記(x)的標準差。 At 624, the statistics module 524 determines a first correlation coefficient (CorrA) based on the most recently stored timestamp of the quantity (e.g., 20) and the most recently stored value of the first average of the quantity (e.g., 20). The first correlation coefficient can be, for example, a Pearson correlation coefficient. The statistics module 524 can determine the first correlation coefficient using the following equation:

where CorrA is the first correlation coefficient, Cov(x,y) is the covariance of the most recently stored value of the first mean (y) and the most recently stored timestamp (x), _σy is the standard deviation of the most recently stored value of the first mean (y), and _σx is the standard deviation of the most recently stored timestamp (x).

At 628, the statistics module 524 determines a standard deviation σ _y of the most recently stored values of the quantity for the first mean (y). At 632, the statistics module 524 determines a standard deviation σ _x of the most recently stored values of the quantity for the timestamp (x).

At 636, the statistics module 524 determines a first slope based on the first correlation coefficient, the standard deviation σ _x of the most recently stored timestamp (x), and the standard deviation σ _y of the most recently stored values of the first average (y). For example, the statistics module 524 can use the following equation to set the first slope: SlopeA = CorrA * σ _y / σ _x where SlopeA is the first slope, CorrA is the first correlation coefficient, σ _x is the standard deviation of the most recently stored timestamp (x), and σ _y is the standard deviation of the most recently stored values of the first average (y).

At 640, the debug module 528 determines whether the first slope is outside a slope range. This slope range can be calibrated and can be, for example, about -1.0 to about +1.0 or another suitable range. If 640 is true, control continues with 700, which will be discussed further below. If 640 is false, control transfers to 644.

其中CorrB是第二相關係數，Cov(x,y)是最近儲存的時間戳記(x)和第二平均值(y)的最近儲存數值的共變異數，σ_x是最近儲存的時間戳記(x)的標準差，而σ_y是第二平均值(y)的最新儲存數值的標準差。 At 644, the statistics module 524 determines a second correlation coefficient (CorrB) based on the most recently stored timestamp of the number (e.g., 20) and the most recently stored value of the second average of the number (e.g., 20). The second correlation coefficient can be, for example, a Pearson correlation coefficient. The statistics module 524 can determine the second correlation coefficient using the equation:

Where CorrB is the second correlation coefficient, Cov(x,y) is the covariance of the most recently stored timestamp (x) and the most recently stored value of the second mean (y), _σx is the standard deviation of the most recently stored timestamp (x), and _σy is the standard deviation of the most recently stored value of the second mean (y).

At 648, the statistics module 524 determines a standard deviation _σy of the most recently stored value of the second mean (y) of the quantity. At 652, the statistics module 524 determines a standard deviation _σx of the most recently stored timestamp (x) of the quantity.

At 656, the statistics module 524 determines a second slope based on the second correlation coefficient, the standard deviation σ _x of the most recently stored time stamp (x), and the standard deviation σ _y of the most recently stored values of the second average (y). For example, the statistics module 524 can use the equation to set the second slope: SlopeB = CorrB * σ _y / σ _x where SlopeB is the second slope, CorrB is the second correlation coefficient, σ _x is the standard deviation of the most recently stored time stamp (x), and σ _y is the standard deviation of the most recently stored values of the second average (y).

At 660, the debug module 528 determines whether the second slope is outside of a slope range (e.g., approximately -1.0 to approximately +1.0). If 660 is true, control continues with 700, which will be discussed further below. If 660 is false, control transfers to 664.

其中CorrC是第三相關係數，Cov(x,y)是最近儲存的時間戳記(x)與第三平均值(y)的最近儲存數值的共變異數，σ_x是最近儲存的時間戳記(x)的標準差，而σ_y是第三平均值(y)的最新儲存值的標準差。 At 664, the statistics module 524 determines a third correlation coefficient (CorrC) based on the most recently stored timestamp of the quantity (e.g., 20) and the most recently stored value of the third average of the quantity (e.g., 20). The third correlation coefficient can be, for example, a Pearson correlation coefficient. The statistics module 524 can determine the third correlation coefficient using the equation:

Where CorrC is the third correlation coefficient, Cov(x,y) is the covariance of the most recently stored timestamp (x) and the most recently stored values of the third mean (y), _σx is the standard deviation of the most recently stored timestamp (x), and _σy is the standard deviation of the most recently stored values of the third mean (y).

At 668, the statistics module 524 determines the standard deviation σ _y of the most recently stored value of the third mean (y) of the quantity. At 672, the statistics module 524 determines the standard deviation σ _x of the most recently stored timestamp (x) of the quantity.

At 676, the statistics module 524 determines a third slope based on the third correlation coefficient, the standard deviation σ _x of the most recently stored time stamp (x), and the standard deviation σ _y of the most recently stored values of the third mean (y). For example, the statistics module 524 can use the equation to set the third slope: SlopeC = CorrC * σ _y / σ _x where SlopeC is the third slope, CorrC is the third correlation coefficient, σ _x is the standard deviation of the most recently stored time stamp (x), and σ _y is the standard deviation of the most recently stored values of the third mean (y).

At 680, the debug module 528 determines whether the third slope is outside of a slope range (e.g., approximately -1.0 to approximately +1.0). If 680 is true, control continues with 700, which will be discussed further below. If 680 is false, control transfers to 684.

其中CorrD是第四相關係數，Cov(x,y)是最近儲存的時間戳記(x)與第四平均值(y)的最近儲存數值的共變異數，σ_x是最近儲存的時間戳記(x)的標準差，而σ_y是第四平均值(y)的最新儲存數值的標準差。 At 684, the statistics module 524 determines a fourth correlation coefficient (CorrD) based on the most recently stored timestamp of the quantity (e.g., 20) and the most recently stored value of the fourth average of the quantity (e.g., 20). The fourth correlation coefficient can be, for example, a Pearson correlation coefficient. The statistics module 524 can determine the fourth correlation coefficient using the equation:

Where CorrD is the fourth correlation coefficient, Cov(x,y) is the covariance of the most recently stored timestamp (x) and the most recently stored value of the fourth mean (y), _σx is the standard deviation of the most recently stored timestamp (x), and _σy is the standard deviation of the most recently stored value of the fourth mean (y).

At 688, the statistics module 524 determines a standard deviation _σy of the most recently stored value of the fourth mean (y) of the quantity. At 692, the statistics module 524 determines a standard deviation _σx of the most recently stored timestamp (x) of the quantity.

At 694, the statistics module 524 determines a fourth slope based on the fourth correlation coefficient, the standard deviation σ _x of the most recently stored timestamp (x) of the quantity, and the standard deviation σ _y of the most recently stored values of the fourth mean (y) of the quantity. For example, the statistics module 524 can use the following equation to set the fourth slope: SlopeD = CorrD * σ _y / σ _x where SlopeD is the fourth slope, CorrD is the fourth correlation coefficient, σ _x is the standard deviation of the most recently stored timestamp (x) of the quantity, and σ _y is the standard deviation of the most recently stored values of the fourth mean (y) of the quantity.

At 696, the debug module 528 determines whether the fourth slope is outside of a slope range (e.g., approximately -1.0 to approximately +1.0). If 696 is yes, control continues to 700. If 696 is no, the temperature of the base plate is not changing rapidly, and control continues to 740 (via P) of FIG. 7.

At 700, the baseplate temperature module 512 determines whether the second signal (flag B) is set to a first state, such as a digital 0. The second signal being set to the first state indicates that the baseplate temperature module 512 determines the baseplate temperature based on measurements from all four temperature sensors 308. If 700 is false, control passes to 708. If 700 is true, the baseplate temperature module 512 determines the baseplate temperature based on the first, second, third, and fourth averages at 704. This can bypass the verification of the accuracy of the temperature sensors 308 and can avoid possible misidentification of an error when the baseplate temperature changes rapidly. The baseplate temperature module 512 can set the baseplate temperature based on, for example, or equal to the average of the first, second, third, and fourth averages (determined at 608-620). For example, the baseplate temperature module 512 outputs the baseplate temperature at 736 for use in determining the substrate temperature.

At 708, the baseplate temperature module 512 determines whether the second signal (flag B) is set to a second state, such as a digital 1. The second signal being set to the second state indicates that the baseplate temperature module 512 determines the baseplate temperature based on the first, second, and third measurements from the temperature sensor 308. If 708 is false, control transfers to 716. If 708 is true, the baseplate temperature module 512 determines the baseplate temperature based on the first, second, and third averages at 712. For example, the baseplate temperature module 512 may set the baseplate temperature based on or equal to the average of the first, second, and third averages (determined at 608-616). Control continues to 736.

At 716, the baseplate temperature module 512 determines whether the second signal (flag B) is set to a third state, such as a number 2. The second signal being set to the third state indicates that the baseplate temperature module 512 determines the baseplate temperature based on measurements from the first, second, and fourth temperature sensors 308. If 716 is false, control transfers to 724. If 716 is true, the baseplate temperature module 512 determines the baseplate temperature based on the first, second, and fourth averages at 720. For example, the baseplate temperature module 512 may set the baseplate temperature based on or equal to the average of the first, second, and fourth averages (determined at 608, 612, and 620). Control continues to 736.

At 724, the baseplate temperature module 512 determines whether the second signal (flag B) is set to a fourth state, such as the number 3. The second signal being set to the fourth state indicates that the baseplate temperature module 512 determines the baseplate temperature based on the measurements from the first, third, and fourth temperature sensors 308. If 724 is true, the baseplate temperature module 512 determines the baseplate temperature based on the first, third, and fourth averages at 728. For example, the baseplate temperature module 512 may set the baseplate temperature based on or equal to the average of the first, third, and fourth averages (determined at 608, 616, and 620). Control continues to 736. If 724 is false, the baseplate temperature module 512 determines the baseplate temperature based on the second, third, and fourth averages at 732. For example, the baseplate temperature module 512 may set the baseplate temperature based on or equal to the average of the second, third, and fourth averages (determined at 612-620). Control continues to 736.

Now referring to FIG. 7 , at 740 , the statistics module 524 determines a first range of the first, second, third, and fourth averages. The statistics module 524 determines a minimum (minimum) of the first, second, third, and fourth averages, and a maximum (maximum) of the first, second, third, and fourth averages. The statistics module 524 sets the first range to the difference between the minimum and maximum of the first, second, third, and fourth averages.

At 744, the debug module 528 determines whether the first range is less than the first temperature range (e.g., approximately 1 degree Celsius). If 744 is false, control continues with 748. If 744 is true, control continues with 756, which will be discussed further below. At 748, the debug module 528 determines whether the first signal (flag A) is set to a first state, such as a digital 0. The first signal set to the first state can indicate that measurements from all four temperature sensors 308 are used to determine the baseplate temperature. If 748 is false, control transfers to 784, which will be discussed further below. If 748 is true, the debugging module 528 sets the first signal (flag A) to a second state, such as digital 1 at 752, and control continues to 784. The first signal set to the second state can indicate that the determination of the baseplate temperature is transitioning from using all four temperature sensors 308 to using less than all four temperature sensors 308.

At 756 (when 744 is true), the baseplate temperature module 512 determines an average temperature based on the first, second, third, and fourth averages. For example, the baseplate temperature module 512 may set the average temperature based on or equal to the average of the first, second, third, and fourth averages (determined at 608-620).

At 760, the debug module 528 determines whether the first signal (flag A) is set to a third state, such as the number 2. If 760 is true, then at 764 the debug module 528 determines whether the average temperature determined at 756 is within a second temperature of the stored temperature (e.g., approximately 0.5 degrees Celsius or 0.25 degrees Celsius). The stored temperature is the last value of the baseplate temperature output by the baseplate temperature module 512. If 764 is false, control transfers to 784, which is discussed further below. If 764 is true, then at 768, the baseplate temperature module 512 sets the stored temperature to the average temperature determined at 756. The baseplate temperature module 512 outputs the average temperature determined at 756 as the baseplate temperature at 772. The 764 ensures that changes in the output baseplate temperature are limited to being below a second temperature. This ensures that the temperature probe measurement does not vary in value depending on the determined baseplate temperature.

At 776, the debug module 528 sets the first signal (flag A) to a first state, such as digital 0. At 780, the debug module 528 sets the second signal (flag B) to a first state, such as digital 0. Control then returns to 604 for the next timestamp via U.

At 784, the statistics module 524 determines a second range of the first, second, and third averages. The statistics module 524 determines the minimum (minimum) of the first, second, and third averages, and the maximum (maximum) of the first, second, and third averages. The statistics module 524 sets the second range to the difference between the minimum and maximum of the first, second, and third averages.

At 788, the debug module 528 determines whether the second range is less than the first temperature range (e.g., approximately 1 degree Celsius). If 788 is false, control continues with 820 (via R) of FIG. 8, which will be discussed further below. If 788 is true, control continues with 792.

At 792, the baseplate temperature module 512 determines an average temperature based on the first, second, and third averages. For example, the baseplate temperature module 512 may set the average temperature based on or equal to the average of the first, second, and third averages (determined at 608-616).

At 796, the debug module 528 determines whether the first signal (flag A) is set to a second state, such as a digital 1. If 796 is false, control continues to 804. If 796 is true, at 800, the debug module 528 determines whether the average temperature determined at 792 is within a second temperature (e.g., approximately 0.5 degrees Celsius or 0.25 degrees Celsius) of the stored temperature. If 800 is false, control transfers to 820, which will be discussed further below. If 800 is true, control continues to 804. At 804, the baseplate temperature module 512 sets the stored temperature to the average temperature determined at 792. At 808, the baseplate temperature module 512 outputs the average temperature determined at 792 as the baseplate temperature. 800 ensures that the variation of the output baseplate temperature is limited to be less than the second temperature.

At 812, the debugging module 528 sets the first signal (flag A) to a third state, such as the digital 2. At 816, the debugging module 528 sets the second signal (flag B) to a second state, such as the digital 1. Control then returns to 604 for the next timestamp via U.

Referring to 820 of FIG. 8 , the statistical module 524 determines a third range of the first, second, and fourth averages. The statistical module 524 determines the minimum value (minimum) among the first, second, and fourth averages, and the maximum value (maximum) among the first, second, and fourth averages. The statistical module 524 sets the third range to the difference between the minimum value and the maximum value among the first, second, and fourth averages.

At 824, the debug module 528 determines whether the third range is less than the first temperature range (e.g., approximately 1 degree Celsius). If 824 is false, control continues with 852, which will be discussed further below. If 824 is true, control continues with 828.

At 828, the baseplate temperature module 512 determines an average temperature based on the first, second, and fourth averages. The baseplate temperature module 512 may set the average temperature, for example, based on or equal to the average of the first, second, and fourth averages (determined at 608, 612, and 620).

At 832, the debug module 528 determines whether the first signal (flag A) is set to a second state, such as a digital 1. If 832 is false, control continues to 836. If 832 is true, at 834, the debug module 528 determines whether the average temperature determined at 828 is within a second temperature of the stored temperature (e.g., approximately 0.5 degrees Celsius or 0.25 degrees Celsius). If 834 is false, control transfers to 852, which will be discussed further below. If 834 is true, control continues to 836. At 836, the baseplate temperature module 512 sets the stored temperature to the average temperature determined at 828. At 840, the baseplate temperature module 512 outputs the average temperature determined at 828 as the baseplate temperature. 834 ensures that the variation of the output baseplate temperature is limited to be less than the second temperature.

At 844, the debugging module 528 sets the first signal (flag A) to a third state, such as the number 2. At 848, the debugging module 528 sets the second signal (flag B) to a third state, such as the number 2. Control then returns to 604 at the next timestamp via U.

At 852, the statistics module 524 determines a fourth range of the first, third, and fourth averages. The statistics module 524 determines the minimum (minimum) of the first, third, and fourth averages, and the maximum (maximum) of the first, third, and fourth averages. The statistics module 524 sets the fourth range to the difference between the minimum and maximum of the first, third, and fourth averages.

At 856, the debug module 528 determines whether the fourth range is less than the first temperature range (e.g., approximately 1 degree Celsius). If 856 is false, control continues to 888 (via Q) of FIG. 9, which will be discussed further below. If 856 is true, control continues to 860.

At 860, the baseplate temperature module 512 determines an average temperature based on the first, third, and fourth averages. The baseplate temperature module 512 may set the average temperature, for example, based on or equal to the average of the first, third, and fourth averages (determined at 608, 616, and 620).

At 864, the debug module 528 determines whether the first signal (flag A) is set to a second state, such as a digital 1. If 864 is false, control continues to 872. If 864 is true, at 868, the debug module 528 determines whether the average temperature determined at 860 is within a second temperature (e.g., approximately 0.5 degrees Celsius or 0.25 degrees Celsius) of the stored temperature. If 868 is false, control transfers to 888 of FIG. 9, which will be discussed further below. If 868 is true, control continues to 872. At 872, the baseplate temperature module 512 sets the stored temperature to the average temperature determined at 860. At 876, the baseplate temperature module 512 outputs the average temperature determined at 860 as the baseplate temperature. 868 ensures that the variation of the output baseplate temperature is limited to be less than the second temperature.

At 880, the debugging module 528 sets the first signal (flag A) to a third state, such as the number 2. At 884, the debugging module 528 sets the second signal (flag B) to a fourth state, such as the number 3. Control then returns to 604 at the next timestamp via U.

Now referring to 888 of FIG. 9 , the statistical module 524 determines a fifth range of the second, third, and fourth averages. The statistical module 524 determines the minimum value (minimum) among the second, third, and fourth averages, and the maximum value (maximum) among the second, third, and fourth averages. The statistical module 524 sets the fifth range to the difference between the minimum value and the maximum value among the second, third, and fourth averages.

At 892, the debug module 528 determines whether the fifth range is less than the first temperature range (e.g., approximately 1 degree Celsius). If 892 is false, any combination of three of the temperature sensors 308 are not within the first temperature range, and control continues with 924, which is discussed further below. If 892 is true, control continues with 896.

At 896, the baseplate temperature module 512 determines an average temperature based on the second, third, and fourth averages. The baseplate temperature module 512 may set the average temperature, for example, based on or equal to the average of the second, third, and fourth averages (determined at 612-620).

At 900, the debug module 528 determines whether the first signal (flag A) is set to a second state, such as a digital 1. If 900 is false, control continues to 908. If 900 is true, at 904, the debug module 528 determines whether the average temperature determined at 896 is within a second temperature (e.g., approximately 0.5 degrees Celsius or 0.25 degrees Celsius) of the stored temperature. If 904 is false, control transfers to 924, which will be discussed further below. If 904 is true, control continues with 908.

At 908, the baseplate temperature module 512 sets the stored temperature to the average temperature determined at 896. At 912, the baseplate temperature module 512 outputs the average temperature determined at 896 as the baseplate temperature. 904 ensures that the variation of the output baseplate temperature is limited to be less than the second temperature.

At 916, the debugging module 528 sets the first signal (flag A) to a third state, such as the number 2. At 920, the debugging module 528 sets the second signal (flag B) to a fifth state, such as the number 4. Control then returns to 604 for the next timestamp via T and U.

At 924, the debug module 528 diagnoses a fault in the temperature probe 216. The debug module 528 may also take one or more other actions. For example, the debug module 528 may display a predetermined message related to the fault in the temperature probe 216 on the display 526. Additionally or alternatively, the debug module 528 may cause the system control module 160 to stop substrate processing. For example, the debug module 528 may cause the system control module 160 to actuate the gas delivery system 130 and stop the flow of one or more gases to the processing chamber 102. Additionally or alternatively, the debug module 528 may cause the system control module 160 to adjust the RF generation system 120 to stop powering one, more than one, or all components within the processing chamber 102. The debug module 528 may disable the baseplate temperature module 512 at 928. Control may return to 604 via T and U, or may wait until the fault is cleared or repaired.

Although an example of a temperature probe 216 associated with the base plate 110 is provided, the above-described debugging and management also applies to the temperature sensor 204 as a temperature probe. In addition, although an example of a temperature probe 216 having four temperature sensors is provided, the temperature probe 216 may include more than four temperature sensors.

The foregoing description is merely illustrative in nature and is in no way intended to limit the present disclosure, its application, or use. The broad teachings of the present disclosure can be implemented in a variety of forms. Therefore, although the present disclosure includes specific examples, the true scope of the present disclosure should not be so limited, because other modifications will become apparent after studying the drawings, the specification, and the scope of the following patent applications. It should be understood that one or more steps within the method can be performed in a different order (or simultaneously) without changing the principles of the present disclosure. In addition, although each of the embodiments is described above as having certain features, any one or more of those features described with respect to any embodiment of the present disclosure can be implemented in and/or combined with the features of any other embodiment, even if the combination is not explicitly described. In other words, the described embodiments are not mutually exclusive, and substitution of one or more embodiments with each other is still within the scope of the present disclosure.

Various terms are used to describe the spatial and functional relationships between elements (e.g., between modules, circuit elements, semiconductor layers, etc.), including "connected", "joined", "coupled", "adjacent", "next to", "on top of", "above", "below", and "disposed". Unless explicitly described as "directly", when a relationship between a first element and a second element is described in the above disclosure, the relationship may be a direct relationship in which no other intermediate elements exist between the first element and the second element, but may also be an indirect relationship in which one or more intermediate elements exist (in space or function) between the first and second elements. As used herein, the term at least one of A, B, and C should be interpreted using a non-exclusive logical OR to mean logical (A OR B OR C), and should not be interpreted to mean "at least one A, at least one B, and at least one C".

In some embodiments, the controller is part of a system, which may be part of the examples described above. Such a system may include semiconductor processing equipment, including one or more processing tools, one or more chambers, one or more platforms for processing, and/or specific processing components (wafer pedestals, airflow systems, etc.). These systems may be integrated with electronic devices to control their operation before, during, and after processing of semiconductor wafers or substrates. The electronic devices may be referred to as "controllers" that can control various components or sub-components of one or more systems. Depending on the processing requirements and/or the type of system, the controller may be programmed to control any of the processes disclosed herein, including the delivery of process 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 operation settings, wafer transport to and from tools and other transport tools and/or load lock chambers connected or interfaced with a particular system.

Broadly 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, and the like. The integrated circuits may include a chip in the form of firmware that stores program instructions, a digital signal processor (DSP), a chip defined as an application specific integrated circuit (ASIC), and/or one or more microprocessors or microcontrollers that execute program instructions (e.g., software). The program instructions may be instructions, in the form of various individual settings (or program files) sent to the controller that define operating parameters for performing specific processes on or for a semiconductor wafer or system. In some embodiments, the operating parameters may be part of a recipe defined by a process engineer to perform one or more processing steps during the fabrication of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and/or dies of a wafer.

In some embodiments, the controller can be part of or coupled to a computer that is integrated with the system, coupled to the system, otherwise networked to the system, or a combination thereof. For example, the controller can be in the "cloud" or in all or a portion of a wafer fab host computer system, which can allow remote access to wafer processing. The computer can allow remote access to the system to monitor the current progress of manufacturing operations, review the history of past manufacturing operations, review trends or performance indicators from multiple manufacturing operations, to change parameters of the current process, to set processing steps after the current process, or to start a new process. In some examples, a remote computer (e.g., a server) can provide process recipes to the system over a network, which can include a local area network or the Internet. The remote computer may include a user interface that allows for the input or programming of parameters and/or settings, which are then 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 processing step to be performed during one or more operations. It should be understood that the parameters may be specific to the type of process to be performed and the type of machine with which the controller is configured to interface or control. Thus, as described above, the controller may be decentralized, such as by including one or more discrete controllers that are networked together and work toward a common purpose (e.g., the processes and controls described herein). An example of a distributed controller for this purpose would be one or more integrated circuits in a chamber that communicate with one or more integrated circuits remotely configured (e.g., at the platform level or as part of a remote computer) that combine to control the process on the chamber.

Without limitation, exemplary systems may include plasma etch chambers or modules, deposition chambers or modules, spin rinse chambers or modules, metal plating chambers or modules, cleaning chambers or modules, bevel etch chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, atomic layer deposition (ALD) chambers or modules, atomic layer etch (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, and any other semiconductor processing system that may be associated or used in the fabrication and/or production of semiconductor wafers.

As described above, depending on the process step or steps to be performed by the tool, the controller may communicate with other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, nearby tools, tools throughout the factory, a host computer, another controller, or tools used for material transport (these tools move wafer containers into and out of tool locations and/or loading ports in a semiconductor manufacturing facility).

110: Base plate

216: Temperature probe

304: Thermal conductor

306: Bottom surface

308: Temperature sensor

Claims (41)

A substrate processing system includes: a substrate support in a processing chamber for vertically supporting a substrate; a temperature probe including: a first temperature sensor for measuring a first temperature of the substrate support; a second temperature sensor for measuring a second temperature of the substrate support; a third temperature sensor for measuring a third temperature of the substrate support; and a fourth temperature sensor for measuring a fourth temperature of the substrate support; and a temperature module for: in a first state, based on the first, second, and third temperature sensors, measuring a first temperature of the substrate support; and a temperature module for measuring a fourth temperature of the substrate support. The invention relates to a method for determining a substrate support temperature of the substrate support based on all of the first, second, third, and fourth temperatures; in a second state, determining the substrate support temperature of the substrate support based on only three of the first, second, third, and fourth temperatures; a temperature control module configured to control at least one of heating and cooling of the substrate support based on the substrate support temperature; a statistical module configured to determine a slope of a line based on multiple values of the first temperature; and a detection module configured to diagnose whether the slope is within a slope range. A substrate processing system as claimed in claim 1, wherein the temperature module sets the substrate support temperature based on an average of at least three of the first, second, third, and fourth temperatures. A substrate processing system as claimed in claim 1, wherein: the substrate support comprises: an upper portion for vertically supporting the substrate; and a bottom plate for vertically supporting the upper portion; the first temperature sensor is used to measure the first temperature of the bottom plate; the second temperature sensor is used to measure the second temperature of the bottom plate; the third temperature sensor is used to measure the third temperature of the bottom plate; and the fourth temperature sensor is used to measure the fourth temperature of the bottom plate. A substrate processing system as claimed in claim 1, wherein: the substrate support comprises: an upper portion for vertically supporting the substrate; and a bottom plate for vertically supporting the upper portion; the first temperature sensor is used to measure the first temperature of the upper portion; the second temperature sensor is used to measure the second temperature of the upper portion; the third temperature sensor is used to measure the third temperature of the upper portion; and the fourth temperature sensor is used to measure the fourth temperature of the upper portion. A substrate processing system as claimed in claim 1, wherein the temperature module is used to determine the substrate support temperature based on at least three of the following: a first average value of X first temperatures, where X is an integer greater than one; a second average value of X second temperatures; a third average value of X third temperatures; and a fourth average value of X fourth temperatures. A substrate processing system as claimed in claim 5, wherein the temperature module is used to determine the substrate support temperature based on an average of at least three of the first average value, the second average value, the third average value, and the fourth average value. A substrate processing system as claimed in claim 5, wherein when a first difference between the maximum of the first average value, the second average value, the third average value, and the fourth average value and the minimum of the first average value, the second average value, the third average value, and the fourth average value is less than a temperature, the temperature module determines the substrate support temperature based on all of the first average value, the second average value, the third average value, and the fourth average value. A substrate processing system as claimed in claim 7, wherein when the first difference is greater than the substrate support temperature, the temperature module selectively determines the substrate support temperature based on three of the first, second, third, and fourth average values. A substrate processing system as claimed in claim 8, wherein when a second difference between a second maximum value among the first average value, the second average value, and the third average value and a second minimum value among the first average value, the second average value, and the third average value is less than the substrate support temperature, the temperature module determines the substrate support temperature based on the first, second, and third average values and not based on the fourth average value. A substrate processing system as claimed in claim 9, wherein when a third difference between a third maximum value among the first average value, the second average value, and the fourth average value and a third minimum value among the first average value, the second average value, and the fourth average value is less than the substrate support temperature, the temperature module determines the substrate support temperature based on the first, second, and fourth average values and not based on the third average value. A substrate processing system as claimed in claim 10, wherein when a fourth difference between a fourth maximum value among the first average value, the third average value, and the fourth average value and a fourth minimum value among the first average value, the third average value, and the fourth average value is less than the substrate support temperature, the temperature module determines the substrate support temperature based on the first, third, and fourth average values and not based on the second average value. A substrate processing system as claimed in claim 11, wherein when a fifth difference between a fifth maximum value among the second average value, the third average value, and the fourth average value and a fifth minimum value among the second average value, the third average value, and the fourth average value is less than the substrate support temperature, the temperature module determines the substrate support temperature based on the second, third, and fourth average values and not based on the first average value. A substrate processing system as claimed in claim 12, wherein when the first, second, third, fourth, and fifth differences are greater than the substrate support temperature, the debugging module indicates that a fault exists in the temperature probe. A substrate processing system as claimed in claim 13, wherein when the fault exists in the temperature probe, the debugging module displays an alarm on a display. A substrate processing system as claimed in claim 1, wherein the first, second, third, and fourth temperature sensors are solid-state temperature sensors. The substrate processing system of claim 1 further comprises a thermally conductive material sandwiched between the substrate support and the first, second, third, and fourth temperature sensors. A substrate processing system as claimed in claim 1, wherein the statistical module is used to: determine a first average value of multiple values of the first temperature; determine a second average value of multiple values of the first average value; determine a first standard deviation of the multiple values of the first average value; determine a second standard deviation of multiple time stamps associated with the multiple values of the first average value; determine a correlation coefficient based on the multiple time stamps and the multiple values of the first average value; determine the slope of the line based on the correlation coefficient, the first standard deviation, and the second standard deviation. The substrate processing system of claim 17, wherein the statistical module determines the correlation coefficient based on (a) the covariance of the plurality of values of the first mean and the plurality of time stamps, (b) the first standard deviation, and (c) the second standard deviation. A substrate processing system as claimed in claim 17, wherein the statistical module sets the slope based on the correlation coefficient multiplied by the first standard deviation divided by the second standard deviation. A substrate processing system as claimed in claim 1, wherein the temperature control module is used to perform at least one of the following: selectively apply power to a thermal control element (TCE) based on the temperature of the substrate support; and selectively adjust the coolant flow through the coolant channel in the substrate support based on the temperature of the substrate support. A substrate processing system includes: a substrate support in a processing chamber for vertically supporting a substrate; a temperature probe including: N temperature sensors for respectively measuring N temperatures of the substrate support, wherein N is an integer greater than 3; a temperature module for: in a first state, determining a substrate support temperature of the substrate support based on all of the N temperatures; in a second state, determining the substrate support temperature of the substrate support based on a subset of the N temperatures; a temperature control module for controlling at least one of heating and cooling of the substrate support based on the substrate support temperature; a statistical module for determining a slope of a line based on multiple values of one of the N temperatures; and a detection module for diagnosing whether the slope is within a slope range. A method for controlling the temperature of a substrate support, the method comprising: measuring a first temperature of the substrate support vertically supporting a substrate during substrate processing by a first temperature sensor of a temperature probe; measuring a second temperature of the substrate support by a second temperature sensor of the temperature probe; measuring a third temperature of the substrate support by a third temperature sensor of the temperature probe; measuring a fourth temperature of the substrate support by a fourth temperature sensor of the temperature probe; ; in a first state, determining a substrate support temperature of the substrate support based on all of the first, second, third, and fourth temperatures; in a second state, determining the substrate support temperature of the substrate support based on only three of the first, second, third, and fourth temperatures; controlling at least one of heating and cooling of the substrate support based on the substrate support temperature; determining a slope of a line based on multiple values of the first temperature; and diagnosing whether the slope is within a slope range. A method for controlling the temperature of a substrate support as claimed in claim 22, wherein the step of determining the temperature of the substrate support comprises: setting the temperature of the substrate support based on an average value of at least three of the first, second, third, and fourth temperatures. A method for controlling the temperature of a substrate support as claimed in claim 22, wherein: the substrate support comprises: an upper portion for vertically supporting the substrate; and a bottom plate for vertically supporting the upper portion; the step of measuring the first temperature comprises measuring the first temperature of the bottom plate; the step of measuring the second temperature comprises measuring the second temperature of the bottom plate; the step of measuring the third temperature comprises measuring the third temperature of the bottom plate; and the step of measuring the fourth temperature comprises measuring the fourth temperature of the bottom plate. A method for controlling the temperature of a substrate support as claimed in claim 22, wherein: the substrate support comprises: an upper portion for vertically supporting the substrate; and a bottom plate for vertically supporting the upper portion; the step of measuring the first temperature comprises measuring the first temperature of the upper portion; the step of measuring the second temperature comprises measuring the second temperature of the upper portion; the step of measuring the third temperature comprises measuring the third temperature of the upper portion; and the step of measuring the fourth temperature comprises measuring the fourth temperature of the upper portion. A method for controlling the temperature of a substrate support as claimed in claim 22, wherein the step of determining the temperature of the substrate support comprises determining the temperature of the substrate support based on at least three of the following: a first average value of X first temperatures, where X is an integer greater than one; a second average value of X second temperatures; a third average value of X third temperatures; and a fourth average value of X fourth temperatures. A method for controlling the temperature of a substrate support as claimed in claim 26, wherein the step of determining the temperature of the substrate support comprises: determining the temperature of the substrate support based on an average of at least three of the first average value, the second average value, the third average value, and the fourth average value. A method for controlling the temperature of a substrate support as claimed in claim 26, wherein the step of determining the temperature of the substrate support comprises: when a first difference between the maximum value among the first, second, third, and fourth average values and the minimum value among the first, second, third, and fourth average values is less than a temperature, determining the temperature of the substrate support based on all of the first, second, third, and fourth average values. A method for controlling the temperature of a substrate support as claimed in claim 28, wherein the step of determining the temperature of the substrate support comprises: when the first difference is greater than the temperature of the substrate support, determining the temperature of the substrate support based on three of the first, second, third, and fourth average values. A method for controlling the temperature of a substrate support as claimed in claim 29, wherein the step of determining the temperature of the substrate support comprises: when a second difference between a second maximum value among the first, second, and third average values and a second minimum value among the first, second, and third average values is less than the temperature of the substrate support, determining the temperature of the substrate support based on the first, second, and third average values and not based on the fourth average value. A method for controlling the temperature of a substrate support as claimed in claim 30, wherein the step of determining the temperature of the substrate support comprises: when a third difference between a third maximum value among the first, second, and fourth average values and a third minimum value among the first, second, and fourth average values is less than the temperature of the substrate support, determining the temperature of the substrate support based on the first, second, and fourth average values and not based on the third average value. A method for controlling the temperature of a substrate support as claimed in claim 31, wherein the step of determining the temperature of the substrate support comprises: when a fourth difference between a fourth maximum value among the first, third, and fourth average values and a fourth minimum value among the first, third, and fourth average values is less than the temperature of the substrate support, determining the temperature of the substrate support based on the first, third, and fourth average values and not based on the second average value. A method for controlling the temperature of a substrate support as claimed in claim 32, wherein the step of determining the temperature of the substrate support comprises: when a fifth difference between a fifth maximum value among the second, third, and fourth average values and a fifth minimum value among the second, third, and fourth average values is less than the temperature of the substrate support, determining the temperature of the substrate support based on the second, third, and fourth average values and not based on the first average value. The method of controlling the temperature of a substrate support as claimed in claim 33 further comprises: when the first, second, third, fourth, and fifth differences are greater than the temperature of the substrate support, indicating that a fault exists in the temperature probe. The method of controlling the temperature of a substrate support as claimed in claim 34 further comprises: displaying an alarm on a display when the fault exists in the temperature probe. A method for controlling the temperature of a substrate support as claimed in claim 22, wherein the first, second, third, and fourth temperature sensors are solid-state temperature sensors. A method for controlling the temperature of a substrate support as claimed in claim 22, wherein a thermally conductive material is interposed between the substrate support and the first, second, third, and fourth temperature sensors. The method for controlling the temperature of the substrate support as claimed in claim 22 further comprises: determining a first average value of multiple values of the first temperature; determining a second average value of multiple values of the first average value; determining a first standard deviation of the multiple values of the first average value; determining a second standard deviation of multiple time stamps associated with the multiple values of the first average value; determining a correlation coefficient based on the multiple time stamps and the multiple values of the first average value; determining the slope of the line based on the correlation coefficient, the first standard deviation, and the second standard deviation. A method for controlling the temperature of a substrate support as claimed in claim 38, wherein the step of determining the correlation coefficient comprises: determining the correlation coefficient based on (a) the covariance of the plurality of values of the first average and the plurality of time stamps, (b) the first standard deviation, and (c) the second standard deviation. A method for controlling the temperature of a substrate support as claimed in claim 38, wherein the step of determining the slope comprises: setting the slope based on the correlation coefficient multiplied by the first standard deviation divided by the second standard deviation. A method for controlling the temperature of a substrate support as claimed in claim 22, wherein the step of controlling at least one of heating and cooling of the substrate support comprises at least one of: selectively applying power to a thermal control element (TCE) based on the temperature of the substrate support; and selectively adjusting the coolant flow through a coolant channel in the substrate support based on the temperature of the substrate support.

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