Chucking process and system for substrate processing chamber

Abstract

To provide a method for chucking a substrate that reduces or eliminates backside damage and arcing, and increases yield in a cost-effective manner.SOLUTION: A method of chucking one or more substrates disposed on a support surface of a pedestal in a substrate processing chamber includes the steps of applying a chucking voltage to the pedestal, ramping the chucking voltage from an applied voltage, detecting an impedance shift while ramping the chucking voltage, identifying a corresponding chucking voltage at which the impedance shift occurs, and identifying a refined chucking voltage on the basis of the impedance shift and the corresponding chucking voltage.SELECTED DRAWING: Figure 2

Description

[Background technology]

[0001] Technical Field Aspects of the present disclosure generally relate to methods and systems for operating a substrate processing chamber, including methods for chucking a substrate.

[0002] 2. Description of Related Art

[0002] During substrate processing, the substrate may be chucked to a pedestal in a substrate processing chamber. For example, a bowed substrate may be chucked to a pedestal during processing. However, due to variations in the characteristics of the pedestal and / or variations in the characteristics of the substrate, it is difficult, costly, and time-consuming to specify the chucking voltage that should be applied to the pedestal during processing. If the chucking voltage applied is too low, arcing may occur during substrate processing. If the chucking voltage applied is too high, the substrate may also suffer backside damage, which may lead to defects and reduced yield of the substrate processing process.

[0003] Therefore, what is needed is an improved method of chucking a substrate that reduces or eliminates backside damage and arcing, and increases yield in a cost-effective manner. Summary of the Invention

[0004] Implementations of the present disclosure generally relate to methods and systems for operating a substrate processing chamber, including a method for chucking a substrate.

[0005] In one implementation, a method for chucking one or more substrates in a substrate processing chamber includes applying a chucking voltage to a pedestal. The substrate is disposed on a support surface of the pedestal. The method also includes ramping the chucking voltage from an applied voltage, detecting an impedance shift while ramping the chucking voltage, and identifying a corresponding chucking voltage at which the impedance shift occurs. The method also includes identifying a refined chucking voltage based on the impedance shift and the corresponding chucking voltage.

[0006] In one implementation, a method for chucking one or more substrates in a substrate processing chamber includes applying a chucking voltage to a pedestal using a preselected value, the substrate being positioned on a support surface of the pedestal, detecting an impedance shift, identifying a refined chucking voltage based on the impedance shift, and adjusting the applied chucking voltage using the refined chucking voltage.

[0007] In one implementation, a controller for a substrate processing chamber system includes a processor. The controller includes a set of computer instructions that, when executed, direct the processor to cause a DC voltage generator to apply a chucking voltage to a pedestal. The set of computer instructions, when executed, cause an impedance detector to detect an impedance shift in a radio frequency energy generator and identify a refined chucking voltage based on the impedance shift.

[0008]

[0008] In order that the above-mentioned features of the present disclosure may be understood in detail, a more detailed description of the present disclosure, briefly summarized above, may be obtained by referring to the embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the accompanying drawings only illustrate common embodiments of the present disclosure, since the present disclosure may admit of other equally effective embodiments, and therefore should not be considered as limiting the scope of the present disclosure. [Brief description of the drawings]

[0009] [Figure 1] 1 is a schematic partial cross-sectional view of a substrate processing chamber system according to one implementation. [Diagram 2]

[0010] 1 is a schematic diagram of a method for chucking a substrate in a substrate processing chamber, according to one implementation. [Diagram 3]

[0011] 1 shows an image illustrating impedance shift according to one implementation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010]

[0012] To facilitate understanding, wherever possible, the same reference numbers have been used to designate identical elements that are common to multiple figures. It is contemplated that elements disclosed in one implementation may be beneficially utilized in other implementations without specific recitation.

[0011]

[0013] The present disclosure relates to a method and system for chucking a substrate in a substrate processing chamber. FIG. 1 shows a schematic partial cross-sectional view of a substrate processing chamber system 101 according to one implementation. The substrate processing chamber system 101 includes a chamber 100 in which a pedestal 138 is disposed. The chamber 100 can be, for example, a chemical vapor deposition (CVD) chamber, a plasma enhanced chemical vapor deposition (PECVD) chamber, or a physical vapor deposition (PVD) chamber. The chamber 100 includes a chamber body 102 and a chamber lid 104. The chamber body 102 includes an interior space 106 therein and a pumping passage 108. The interior space 106 is a space defined by the chamber body 102 and the chamber lid 104. The pumping passage 108 is a passage formed in the chamber body 102 that is connected to a pumping space 112 formed in a pumping plate 114. The pumping passage 108 facilitates removal of gas from the interior space 106.

[0012]

[0014] The chamber 100 includes a gas distribution assembly 116 coupled to and / or disposed within the chamber lid 104 to supply a flow of one or more gases into the processing region 110. The processing region 110 includes a portion of the interior space 106 located between the substrate support 138 and the chamber lid 104. The gases supplied by the gas distribution assembly 116 can include, for example, one or more process gases (e.g., one or more inert gases and / or one or more precursor gases). In one example, the one or more process gases include a precursor gas including tetraethylorthosilicate (TEOS) for forming a film on the substrate 136. The gas distribution assembly 116 includes a gas manifold 118 coupled to a gas injection passage 120 formed in the chamber lid 104. The gas manifold 118 receives a flow of gas from one or more gas sources 122 (two gas sources are shown). A flow of gas received from one or more gas sources 122 is dispersed within the gas box 124, flows through a plurality of openings in the backing plate 126, and is further dispersed within a plenum 128 defined by the backing plate 126 and the face plate 130. The flow of gas then flows through a plurality of openings 132 in the face plate 130 into the processing region 110 of the interior space 106. A pump 133 is connected to the pumping path 108 by a conduit 134 for controlling the pressure within the processing region 110 and for evacuating gases and by-products from the processing region 110 through the pumping space 112 and the pumping path 108.

[0013]

[0015] The interior space 106 includes a pedestal 138 that supports a substrate 136 on a support surface 138a of the pedestal 138 within the chamber 100. The pedestal 138 includes an electrode 140 disposed within the pedestal 138. The electrode 140 may include a conductive mesh (e.g., a tungsten-containing, copper-containing, or molybdenum-containing conductive mesh). The electrode 140 may include any material used for heating, including an alternating current (AC) coil. The electrode 140 is coupled to a power source 159 (e.g., a direct current (DC) voltage generator). The electrode 140 is configured to provide a chucking voltage received from the DC voltage generator 159 to the pedestal 138. The chucking voltage applies a chucking force to the substrate 136 such that the substrate 136 is chucked to the support surface 138a of the pedestal 138. An electrostatic force is applied to the substrate 136, attracting the substrate towards the electrode 140 and facilitating chucking of the substrate 136 to the support surface 138a. The chucking force acting on the substrate 136 aids in eliminating bowing of the substrate 136 or in flattening the substrate 136.

[0014]

[0016] The electrode 140 is coupled to a radio frequency (RF) energy generator 156. The electrode 140 is configured to propagate RF received from the RF energy generator 156 through the pedestal 138 and into the processing region 110. The electrode 140 can propagate RF energy, for example, while one or more process gases are present in the processing region 110, thereby generating a plasma 141 in the processing region 110.

[0015]

[0017] The electrode 140 is coupled to a heating power supply 180 that provides heating power to the electrode 140. The heating power can be, for example, alternating current (AC). The electrode 140 is configured to heat the pedestal 138 using the heating power received from the heating power supply 180.

[0016]

[0018] The electrode 140 is coupled to the RF energy generator 156, the heating power supply 180, and the DC voltage generator 159 through the conductive rod 160 and the matching network 158. An impedance detector 190 is coupled to the RF energy generator 156. The impedance detector 190 is configured to detect an impedance shift of the RF energy generator 156 while the DC voltage generator 159 applies a chucking voltage to the pedestal 138 through the electrode 140. In an embodiment, which may be combined with other embodiments, the impedance detector 190 is additionally or alternatively coupled to other components of the substrate processing chamber system 101. For example, the impedance detector 190 may be coupled to, and configured to detect an impedance shift in, one or more of the substrate 136, the pedestal 138, the electrode 140, the heating power supply 180, the DC voltage generator 159, the chamber body 102, the chamber lid 104, the support surface 138a, the face plate 130, the backing plate 126, and / or the second RF energy generator 166. It is contemplated in the present disclosure that the impedance detector 190 may be configured to detect an impedance shift in any component of the substrate processing chamber system 101 and use such information in accordance with aspects disclosed herein.

[0017]

[0019] The pedestal 138 is disposed within the interior space 106 so as to be movable by a stem 142 coupled to a lift system. Movement of the pedestal 138 facilitates transfer of the substrate 136 into and out of the interior space 106 through a slit valve formed through the chamber body 102. The pedestal 138 can also be moved to various processing positions for processing the substrate 136. The pedestal 138 can have an opening disposed therethrough, and a number of lift pins 150 can be disposed to be movable through the opening. In the lowered position, the plurality of lift pins 150 protrude from the pedestal 138 by contacting a lift plate 152 coupled to a bottom 154 of the chamber body. Protruding lift pins 150 position the substrate 136 in spaced relation from the pedestal 138 to facilitate transfer of the substrate 136.

[0018]

[0020] During substrate processing, the electrode 140 heats the pedestal 138 as gases flow into the processing region 110. The electrode 140 also delivers radio frequency (RF) energy, alternating current (AC), or direct current (DC) to promote plasma generation in the processing region 110 and / or promote chucking of the substrate 136 to the pedestal 138 during substrate processing. The heat, gases, and energy from the electrode 140 promote deposition of a film on the substrate 136 during substrate processing.

[0019]

[0021] The faceplate 130 (grounded via a connection to the chamber body 102) and the electrode 140 facilitate the generation of the plasma 141. For example, the RF energy generator 156 provides RF energy to the electrode 140 in the pedestal 138 to facilitate the generation of the plasma 141 between the pedestal 138 and the faceplate 130 of the gas distribution assembly 116. The RF energy generator 156 is connected to a ground 171. A second RF energy generator 166 is also configured to provide RF energy to the chamber 100. The second RF energy generator 166 is connected to a ground 173. Although the second RF energy generator 166 is illustrated, it is contemplated in the present disclosure that other power sources may be used in place of or in conjunction with the second RF energy generator 166. For example, a second alternating current (AC) power source or a second direct current (DC) power source may be used. It is contemplated in the present disclosure that the second AC power source and / or the second DC power source may be coupled to the impedance detector 190.

[0020]

[0022] The substrate processing chamber system 101 includes a controller 192 configured to control one or more of the components of the substrate processing chamber system 101. The controller 192 includes a central processing unit (CPU) 193, support circuits 194, and a memory 195 containing associated control software 196. The CPU 193 may include a processor. The control software 196 includes a set of computer instructions that, when executed, direct the CPU 193 of the controller 192 to cause the performance of one or more operations using one or more components of the substrate processing chamber system 101. The controller 192 may include any form of general-purpose computer processor that may be used in an industrial setting to control various chambers and sub-processors. The CPU 193 may use any suitable memory 195, such as random access memory, read-only memory, floppy disk drive, compact disk drive, hard disk, or any other form of digital storage, local or remote. Various support circuits may be coupled to the CPU 193 to support the chamber 100. The controller 192 may be coupled to other controllers located adjacent to individual chamber components. Bidirectional communication between the controller 192 and various other components of the chamber 100 is handled through a number of signal cables (collectively referred to as a signal bus, some of which are shown in FIG. 1).

[0021]

[0023] 1 is configured to control at least one or more of the gas source 122, the pump 133, the RF energy generator 156, the DC voltage generator 159, the second RF energy generator 166, the heating power supply 180, and the impedance detector 190. In one embodiment, which may be combined with other embodiments, the controller 192 is configured to, when executed by a processor (such as the CPU 193), cause the performance of one or more of the steps illustrated in the method 200 of FIG. 2. In one example, the control software 196 includes a set of computer instructions that, when executed, direct the CPU 193 of the controller 192 to cause the performance of one or more of the steps illustrated in the method 200 of FIG.

[0022]

[0024] 2 is a schematic diagram of a method 200 for chucking a substrate in a substrate processing chamber. In step 201, a chucking voltage is applied to the pedestal and / or radio frequency (RF) energy is provided to the substrate processing chamber while the substrate is disposed on a support surface of the pedestal. In one embodiment, which may be combined with other embodiments, the chucking voltage is applied using a preselected value for the chucking voltage. The preselected value may be obtained, for example, based on the specifications of the processing chamber, the substrate, the pedestal, or the electrodes, or their materials. The preselected value may be obtained from a previous substrate processing or chucking process. In one example, the preselected value is obtained using one or more experimental runs when a new pedestal, chamber, and / or substrate is used in a substrate processing process.

[0023]

[0025] In optional step 203, a plasma (such as an inert plasma) is generated. In optional step 205, the chucking voltage is ramped up or down until an impedance shift occurs. Alternatively, the chucking voltage may be ramped up from the applied voltage to a second, greater voltage to identify the voltage between the applied voltage and the second, greater voltage at which an impedance shift occurs. In one embodiment, which may be combined with other embodiments, the second, greater voltage is a preselected value. In step 207, the impedance shift is detected. The impedance shift signals that the substrate has been chucked to the support surface of the pedestal.

[0024]

[0026] In one embodiment, which may be combined with other embodiments, the chucking voltage is ramped up or down in one or more voltage increments until an impedance shift occurs. In one example, the chucking voltage is ramped upward in 50 volt increments, each applied for 5 seconds or more, e.g., 10 seconds or more, to allow for stabilization of the impedance sensor, until an impedance shift occurs. In one example, the chucking voltage is ramped downward in 100 volt increments, each applied for 5 seconds or more, e.g., 10 seconds or more, until an impedance shift occurs.

[0025]

[0027] An impedance shift is a shift in impedance of at least a predetermined amount (e.g., 0.5 ohms or more). In one embodiment, which may be combined with other embodiments, a first impedance value is measured for a predetermined period of time (e.g., 5 seconds or more, for example, 10 seconds or more) after the chucking voltage is applied in block 201. In such an embodiment, the chucking voltage is ramped in block 205 and the second impedance value is measured after applying the ramped chucking voltage for another equal or different period of time (e.g., about 5 seconds or more, for example, 10 seconds or more). Applying the chucking voltage for a predetermined period of time allows the impedance value to stabilize for accurate measurement. The difference between the first impedance value and the second impedance value indicates an impedance shift. A shift is considered to have occurred if the delta between the measured impedance values ​​exceeds a predetermined threshold amount. In one example, a shift of 0.5 ohms or more indicates that the substrate is chucked and / or that bowing of the substrate is reduced or eliminated. However, it should be noted that other shift values ​​are contemplated.

[0026]

[0028] In one embodiment, which may be combined with other embodiments, the impedance shift is used to verify that the substrate is chucked and / or that bowing of the substrate is reduced or eliminated. In such an embodiment, an impedance shift in block 207 below a target value (e.g., 0.1 ohms or less) is used to verify that the substrate is chucked to the pedestal. In one example, after the impedance shift is measured in block 207, a second impedance shift is measured. If the second impedance shift is below the target value (e.g., 0.1 ohms or less), chucking of the substrate to the pedestal is verified. If the second impedance shift is above a predetermined target value for verifying chucking, the substrate may be at least partially unchucked from the pedestal.

[0027]

[0029] Without being bound by theory, it is believed that the impedance shift is caused by a change in the flow of charge between the substrate and other component(s) of the substrate processing chamber system. For example, chucking the substrate may remove any bowing in the substrate, which may flatten the substrate against the support surface of the pedestal and reduce one or more gaps between the substrate and the support surface. The reduction in one or more gaps between the substrate and the support surface causes a change in the flow of charge between the substrate and other component(s) (such as the pedestal). This change in charge flow causes an impedance shift in one or more components of the substrate processing chamber system.

[0028]

[0030] In one embodiment, which may be combined with other embodiments, detecting the impedance shift includes measuring the impedance shift. A device such as an impedance detector (e.g., impedance detector 190 described above) may be used to detect and / or measure the impedance shift. In one embodiment, which may be combined with other embodiments, the impedance shift is an impedance shift of a radio frequency (RF) energy generating device that provides radio frequency energy to the substrate processing chamber. It is contemplated in the present disclosure that the impedance shift may be detected and / or measured for any component of the substrate processing chamber. In step 209, the impedance shift is used to identify a refined chucking voltage. In one embodiment, which may be combined with other embodiments, the refined chucking voltage is, for example, a minimum voltage value that chucks the substrate to the support surface of the pedestal without any bowing. In one example, the refined chucking voltage is the chucking voltage applied at the moment the impedance shift occurs. Identifying and using the refined chucking voltage facilitates increasing the probability that the substrate is chucked to the support surface of the pedestal in processes involving substrates, chambers, or pedestals having different characteristics. Chuck- ing the substrate facilitates reducing or eliminating bowing of the substrate and also facilitates reducing the probability of arcing by eliminating or reducing the gap between the substrate support surface and the backside of the substrate. Reducing the probability of arcing facilitates reducing substrate defects and increasing the yield of the substrate processing operation. Using the refined chucking voltage also allows an operator the option of not using high chucking voltages that may cause backside damage to the substrate during substrate processing. Reducing the probability of backside damage also reduces the probability of substrate defects and increases the yield of the substrate processing operation.

[0029]

[0031] In one example, the refined chucking voltage may be based on the chucking voltage at the moment of the impedance shift plus an additional voltage amount to ensure chucking. For example, the refined chucking voltage may be equal to the chucking voltage at the moment of the impedance shift plus 5 percent, 10 percent, 15 percent, 20 percent, 25 percent, etc. In such an example, the refined chucking voltage may be identified for a first substrate or a first batch of substrates and then applied to multiple processing runs. The inclusion of the additional voltage amount increases the likelihood that the refined chucking voltage will facilitate chucking and provide the benefits described herein to multiple process substrates without the need to perform method 200 on each substrate during processing. It is also contemplated that method 200 may be performed on each substrate during processing such that the refined chucking voltage is the optimal chucking voltage for that substrate.

[0030]

[0032] In one optional embodiment, which may be combined with other embodiments, the refined chucking voltage is identified by generating a first image of a first impedance trace (e.g., a graph of impedance values ​​versus time for one or more applied voltages) measured while an applied chucking voltage and / or a ramped chucking voltage is applied to the substrate for a predetermined period of time (e.g., 5 seconds or more). The first image of the first impedance trace is compared to a second image of a second impedance trace measured for the same voltage applied to another substrate for the same period of time. In one example, the other substrate is a flat silicon substrate that does not include warping. If the first impedance trace matches the second impedance trace, the applied voltage of the first impedance trace is determined to be the refined chucking voltage. If the first impedance trace does not match the second impedance trace, the applied voltage is ramped until the first impedance trace matches the second impedance trace. In one example, the match of the first impedance trace with the second impedance trace is used to confirm an appropriate voltage value for the refined chucking voltage when the refined chucking voltage is identified using a predetermined quantity, as described above.

[0031]

[0033] By using the impedance shift to identify a refined chucking voltage, the refined chucking voltage may be identified in real time during the substrate processing operation, without the substrate processing operation having to wait until the deposition process on the substrate is completed so that the substrate can be inspected to determine whether the applied chucking voltage is sufficient, which helps to save time and costs during the substrate processing operation, and also helps to increase yield.

[0032]

[0034] In optional step 211, the applied chuck voltage is adjusted to a refined chuck voltage. By adjusting the applied chuck voltage to a refined chuck voltage for a subsequent process, the advantages of the refined chuck voltage described herein may be realized in a timely and cost-effective manner. The refined chuck voltage also allows the substrate processing process to efficiently address and adapt to varying characteristics between different substrates. For example, when a new pedestal is used in a substrate processing process, the pedestal may have a different thermal conductivity than the pedestal used previously. Adjusting the applied chuck voltage using the refined chuck voltage allows the substrate processing process to efficiently adapt to the characteristics of the new pedestal, which may differ from the previous pedestal. This may be done each time a new pedestal is used. As another example, the refined chuck voltage may be used to adjust a preselected value obtained from the specifications of the new pedestal. In one aspect, one or more steps of method 200 are performed each time a new pedestal is used in a substrate processing process.

[0033]

[0035] As another example, when a new substrate is used in a substrate processing chamber, the new substrate may have different bow characteristics than the previously processed substrate. The different bow characteristics may involve a different chucking voltage that may eliminate bowing of the substrate. By utilizing aspects disclosed herein, a chucking voltage that eliminates or reduces bowing may be applied to the substrate without being excessive, thereby reducing the possibility of backside damage.

[0034]

[0036] In optional step 213, the refined chucking voltage is stored. In one embodiment, which may be combined with other embodiments, the refined chucking voltage is stored in memory for use in a subsequent substrate processing step. In optional step 215, the refined chucking voltage is applied. In optional step 217, one or more substrates are chucked to the support surface of the pedestal in response to application of the refined chucking voltage. The one or more substrates in optional step 217 may include the substrate used in step 201. The one or more substrates in optional step 217 may be different from the substrate used in step 201. The one or more substrates in optional step 217 may include a second substrate and / or a third substrate different from the substrate used in step 201.

[0035]

[0037] In optional step 219, bowing of the one or more substrates is reduced or eliminated in response to application of the refined chucking voltage. The one or more substrates in optional step 219 may include the substrate used in step 201. The one or more substrates in optional step 219 may be different from the substrate used in step 201. The one or more substrates in optional step 219 may include a second substrate and / or a third substrate different from the substrate used in step 201.

[0036]

[0038] In optional step 221, a deposition process is performed while applying the refined chucking voltage. For example, a film may be deposited on one or more substrates using one or more process gases, and a processing plasma may be generated to deposit a film on the one or more substrates.

[0037]

[0039] In optional step 223, one or more of steps 201, 203, 205, 207, 209, 211, 213, 215, 217, 219, and / or 221 are repeated for one or more additional substrates. The one or more additional substrates in optional step 223 may include a second substrate and / or a third substrate different from the substrate used in step 201.

[0038]

[0040] Method 200 is not limited to the sequence or number of steps shown in FIG. 2 and may include other implementations, including reordering, repeating, adding, and / or removing one or more of steps 201, 203, 205, 207, 209, 211, 213, 215, 217, 219, 221, and / or 223.

[0039]

[0041] FIG. 3 is an illustration of an image 300 showing an impedance shift according to one implementation. Image 300 shows the impedance shift that occurs after the chucking voltage is ramped up. In the illustrated implementation, a first chucking voltage (e.g., 550 volts) is applied to a substrate for a predetermined period of time (e.g., 20 seconds). A first impedance trace 301 is generated by measuring the impedance for 20 seconds while the first chucking voltage is applied. A first impedance value 302 is measured after the predetermined period of time has elapsed. The chucking voltage is ramped up by a predetermined voltage increment (e.g., 50 volts or about 10 percent) and a second chucking voltage (e.g., 600 volts) is applied to the same substrate for an additional period of time. In one example, the additional period of time is the same as the first period of time (e.g., 20 seconds). A second impedance trace 303 is generated by measuring the impedance for an additional 20 seconds while the second chucking voltage is applied. A second impedance value 304 is measured after a second period of time (e.g., 20 seconds) has elapsed. As shown, the impedance of the second impedance trace 303 is substantially stable after an additional 20 seconds has elapsed. The process is repeated, comparing the stable impedance to the previously stable impedance, until at least a threshold impedance shift is identified.

[0040]

[0042] A difference 305 between the second impedance value 304 and the first impedance value 302 of at least a threshold value (e.g., 0.5 ohms) indicates reduced or eliminated bowing of the substrate. This impedance shift indicates that the second chucking voltage corresponds to a chucking voltage generated by chucking the substrate to the support surface. Thus, excessive application of power for chucking is not required.

[0041]

[0043] It should be noted that image 300 is only one example and other images may be generated or detected. Advantages of the present disclosure include reduced arcing, improved chucking of the substrate to the pedestal support surface, reduced backside damage, timely and efficient adaptation to changes in equipment characteristics, improved yield, and reduced operating costs. Aspects of the present disclosure include applying a chucking voltage to the pedestal, applying a chucking voltage to the pedestal using a preselected value, ramping the chucking voltage until an impedance shift occurs, detecting the impedance shift, identifying a refined chucking voltage based on the impedance shift, and adjusting the applied chucking voltage to the refined chucking voltage.

[0042]

[0044] It is contemplated that one or more of the above aspects disclosed herein may be combined. It is further contemplated that one or more of such aspects may include some or all of the advantages discussed above.

[0043]

[0045] While the above description is directed to embodiments of the present disclosure, other and further embodiments of the present disclosure may be devised without departing from the basic scope of the present disclosure. It is also contemplated in the present disclosure that one or more aspects of the embodiments described herein may be substituted with one or more of the other aspects described. The scope of the present disclosure is determined by the following claims.

Claims

1. 1. A method of chucking one or more substrates in a substrate processing chamber, comprising: applying a chucking voltage to the pedestal while the substrate is disposed on a support surface of the pedestal; ramping the chucking voltage from an applied voltage; detecting an impedance shift while ramping the chucking voltage; identifying a corresponding chuck voltage at which the impedance shift occurred; and and identifying a refined chucking voltage based on the impedance shift and the corresponding chucking voltage.

2. The method of claim 1 , wherein the impedance shift is an impedance shift of a radio frequency energy generating device that supplies radio frequency energy to the substrate processing chamber.

3. 2. The method of claim 1, wherein detecting the impedance shift comprises measuring the impedance shift, the method further comprising applying the refined chucking voltage during a deposition process.

4. 2. The method of claim 1, wherein applying the chucking voltage to the pedestal comprises ramping the chucking voltage until the impedance shift occurs.

5. 2. The method of claim 1 , wherein the refined chucking voltage is a minimum voltage value that chucks the substrate to the support surface of the pedestal, the refined chucking voltage reducing bowing of the substrate, the method further comprising generating a plasma.

6. 2. The method of claim 1 , wherein applying the chucking voltage to the pedestal, detecting the impedance shift, and identifying the refined chucking voltage are repeated for one or more additional substrates.

7. 1. A method of chucking one or more substrates in a substrate processing chamber, comprising: applying a chucking voltage to the pedestal using a preselected value while the substrate is disposed on a support surface of the pedestal; Detecting an impedance shift; and identifying a refined chucking voltage based on the impedance shift; and and adjusting the applied chucking voltage using the refined chucking voltage.

8. The method of claim 7 , wherein the impedance shift is an impedance shift of a radio frequency energy generating device that supplies radio frequency energy to the substrate processing chamber.

9. The method of claim 7 , wherein detecting the impedance shift comprises measuring the impedance shift.

10. The method of claim 7 further comprising performing a deposition process.

11. 8. The method of claim 7, wherein applying the chucking voltage to the pedestal using the preselected value comprises ramping the chucking voltage towards the preselected value until the impedance shift occurs.

12. 8. The method of claim 7, wherein the refined chucking voltage is a minimum voltage value that chucks the substrate to the support surface of the pedestal, the refined chucking voltage reducing bowing of the substrate, the method further comprising generating a plasma.

13. 8. The method of claim 7, wherein applying the chucking voltage to the pedestal, detecting the impedance shift, and identifying the refined chucking voltage are repeated for one or more additional substrates.

14. 1. A controller for a substrate processing chamber system, comprising: A processor; and a set of computer instructions which, when executed, cause the processor to: causing a DC voltage generator to apply a chucking voltage to the pedestal; detecting an impedance shift of the high frequency energy generating device with an impedance detector; and determining a refined chucking voltage based on the impedance shift. controller.

15. The controller of claim 14 , wherein the set of computer instructions, when executed, directs the processor to store the refined chuck voltage in a memory.

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