Adsorption process and system for substrate processing chamber

Abstract

The present disclosure relates to methods and systems for adsorption in a substrate processing chamber. In one embodiment, a method of adsorbing one or more substrates in a substrate processing chamber includes applying an adsorption voltage to a susceptor. A substrate is disposed on a support surface of a susceptor. The method further includes ramping the sorption voltage from the applied voltage; detecting an impedance offset while ramping the adsorption voltage; determining a corresponding adsorption voltage when impedance offset occurs; and determining a precise sorption voltage based on the impedance offset and the corresponding sorption voltage.

Description

This application is a divisional application of the invention patent application with the application date of February 27, 2020, the application number of "202080020738.8", and the invention name of "Adsorption Process and System for Substrate Processing Chamber". Background Art Technical Field

[0001] Aspects of the present disclosure generally relate to methods and systems for operating a substrate processing chamber, including methods for adsorbing a substrate. Description of Related Art

[0002] During the processing of a substrate, the substrate is sometimes adsorbed to a pedestal within a substrate processing chamber. For example, when the substrate is bent, the substrate may be adsorbed to the pedestal during processing. However, due to changes in pedestal characteristics and / or substrate characteristics, it is difficult, expensive, and time-consuming to determine the adsorption voltage that should be applied to the pedestal during processing. If the applied adsorption voltage is too low, arcing may occur during substrate processing. If the applied adsorption voltage is too high, the substrate may also suffer from backside damage, resulting in defects and a reduced yield of substrate processing operations.

[0003] Accordingly, there is a need for an improved method of adsorbing a substrate that reduces or eliminates backside damage and arcing and improves yield in a cost-effective manner. Summary of the Invention

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

[0005] In one embodiment, a method of adsorbing one or more substrates in a substrate processing chamber includes: applying an adsorption voltage to a pedestal. Disposing a substrate on a support surface of the pedestal. The method further includes: ramping the adsorption voltage from the applied voltage; detecting an impedance shift while ramping the adsorption voltage; and determining a corresponding adsorption voltage when the impedance shift occurs. The method further includes: determining an accurate adsorption voltage based on the impedance shift and the corresponding adsorption voltage.

[0006] In one embodiment, a method of adsorbing one or more substrates in a substrate processing chamber includes: applying an adsorption voltage to a pedestal using a preselected value. Disposing a substrate on a support surface of the pedestal. The method further includes: detecting an impedance shift; determining an accurate adsorption voltage based on the impedance shift; and adjusting the applied adsorption voltage using the accurate adsorption voltage.

[0007] In one embodiment, 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 direct current voltage generator to apply an adsorption voltage to a pedestal. The set of computer instructions, when executed, cause an impedance detector to detect an impedance shift of a radio frequency energy generator and determine an exact adsorption voltage based on the impedance shift. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] To understand in detail the manner in which the above-described features of the present disclosure can be obtained, a more specific description of the present disclosure briefly summarized above can be obtained by reference to the embodiments, some of which are illustrated in the accompanying drawings. It should be noted, however, that the drawings only illustrate ordinary embodiments of the present disclosure and should not be considered as limiting its scope, as the present disclosure may admit other equivalent embodiments.

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

[0010] Figure 2 is a schematic illustration of a method for adsorbing a substrate in a substrate processing chamber according to one embodiment.

[0011] Figure 3 is a diagram showing an image of an impedance shift according to one embodiment.

[0012] For the sake of facilitating understanding, the same reference numerals have been used, where possible, to denote the same elements common to the figures. It is contemplated that elements disclosed in one embodiment may be beneficially utilized in other embodiments without specific recitation. DETAILED DESCRIPTION

[0013] The present disclosure relates to methods and systems for adsorbing a substrate in a substrate processing chamber. Figure 1 A partial schematic cross-sectional view of a substrate processing chamber system 101 according to one embodiment is shown. The substrate processing chamber system 101 includes a chamber 100 having a pedestal 138 disposed therein. The chamber 100 can be, for example, a chemical vapor deposition (CVD) chamber, a plasma-enhanced CVD (PECVD) chamber, or a physical vapor deposition (PVD) chamber. The chamber 100 has a chamber body 102 and a chamber lid 104. The chamber body 102 includes an internal volume 106 and a pumping path 108 therein. The internal volume 106 is the space defined by the chamber body 102 and the chamber lid 104. The pumping path 108 is a path formed in the chamber body 102 that is coupled to a pumping volume 112 formed in a pumping plate 114. The pumping path 108 facilitates removal of gas from the internal volume 106.

[0014] Chamber 100 includes a gas distribution assembly 116 that is coupled to and / or disposed within chamber lid 104 to deliver a flow of one or more gases into process region 110. Process region 110 includes a portion of the internal volume 106 located between substrate support 138 and chamber lid 104. The gases delivered by gas distribution assembly 116 can include, for example, one or more process gases (such as 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 that includes tetraethyl orthosilicate (TEOS) to form a film on substrate 136. Gas distribution assembly 116 includes a gas manifold 118 that is coupled to a gas inlet channel 120 formed in chamber lid 104. Gas manifold 118 receives a gas flow from one or more gas sources 122 (two are illustrated). The gas flow received from one or more gas sources 122 is distributed across gas box 124, flows through a plurality of openings in backplate 126, and is further distributed across gas chamber 128 defined by backplate 126 and panel 130. Then, the gas flow flows into process region 110 of internal volume 106 through a plurality of openings 132 in panel 130. Pump 133 is connected to pumping path 108 through conduit 134 to control the pressure within process region 110 and to exhaust gases and by-products from process region 110 through pumping volume 112 and pumping path 108.

[0015] Internal volume 106 includes a pedestal 138 that supports substrate 136 within chamber 100 on a support surface 138a of pedestal 138. Pedestal 138 includes an electrode 140 disposed within pedestal 138. Electrode 140 can include a conductive mesh, such as a tungsten-containing, copper-containing, or molybdenum-containing conductive mesh. Electrode 140 can include any material for heating, including an alternating current (AC) coil. Electrode 140 is coupled to a power supply 159, such as a direct current (DC) voltage generator. Electrode 140 is configured to supply an adsorption voltage received from DC voltage generator 159 to pedestal 138. The adsorption voltage applies an adsorption force to substrate 136 such that substrate 136 is adsorbed to support surface 138a of pedestal 138. The electrostatic force applied to substrate 136 causes the substrate to be pulled downwards towards electrode 140 to facilitate the adsorption of substrate 136 to support surface 138a. The adsorption force acting on substrate 136 facilitates the elimination of the bending of substrate 136 or the flattening of substrate 136.

[0016] Electrode 140 is coupled to a radio frequency (RF) energy generator 156. Electrode 140 is configured to propagate the RF received from RF energy generator 156 through pedestal 138 and into process region 110. For example, when one or more process gases are present in process region 110, electrode 140 can propagate RF energy such that a plasma 141 is generated in process region 110.

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

[0018] Electrode 140 is coupled to RF energy generator 156, heating power supply 180, and DC voltage generator 159 via conductive bar 160 and matching circuit 158. Impedance detector 190 is coupled to RF energy generator 156. Impedance detector 190 is configured to detect an impedance shift of RF energy generator 156 when DC voltage generator 159 applies an adsorption voltage to susceptor 138 via electrode 140. In one embodiment, which can be combined with other embodiments, impedance detector 190 is additionally or alternatively coupled to other components of substrate processing chamber system 101. For example, impedance detector 190 can be coupled to and configured to detect an impedance shift in one or more of substrate 136, susceptor 138, electrode 140, heating power supply 180, DC voltage generator 159, chamber body 102, chamber lid 104, support surface 138a, panel 130, backplane 126, and / or second RF energy generator 166. It is contemplated by the present disclosure that impedance detector 190 can be configured to detect an impedance shift in any component of substrate processing chamber system 101 and use such information in accordance with the aspects disclosed herein.

[0019] Susceptor 138 is movably disposed in interior volume 106 via rod 142 coupled to a lift system. Movement of susceptor 138 facilitates transfer of substrate 136 to and from interior volume 106 through a slit valve formed through chamber body 102. Susceptor 138 can also be moved to different processing positions for processing substrate 136. Susceptor 138 can also have an opening formed therethrough, through which a plurality of lift rods 150 are movably disposed. In a lowered position, the plurality of lift rods 150 project from susceptor 138 by contacting lift plate 152 coupled to the bottom 154 of the chamber body. Projection of lift rods 150 positions substrate 136 in a spaced-apart relationship from susceptor 138 to facilitate transfer of substrate 136.

[0020] During substrate processing, electrode 140 heats susceptor 138 when gas flows into processing region 110. Also during substrate processing, electrode 140 propagates radio frequency (RF) energy, alternating current (AC), or direct current (DC) to facilitate plasma generation in processing region 110 and / or to facilitate adsorption of substrate 136 to susceptor 138. Heat, gas, and energy from electrode 140 facilitate deposition of a film onto substrate 136 during substrate processing.

[0021] The panel 130 and the electrode 140, which are coupled to the chamber body 102 and grounded, facilitate the generation of the plasma 141. For example, the RF energy generator 156 supplies RF energy to the electrode 140 within the susceptor 138 to facilitate the generation of the plasma 141 between the susceptor 138 and the panel 130 of the gas distribution assembly 116. The RF energy generator 156 is connected to the ground 171. The second RF energy generator 166 is also configured to supply RF energy to the chamber 100. The second RF energy generator 166 is connected to the ground 173. Although the second RF energy generator 166 is shown, the present disclosure contemplates that other power sources may be used instead of or in combination 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. The present disclosure contemplates that the second AC power source and / or the second DC power source may be coupled to the impedance detector 190.

[0022] The substrate processing chamber system 101 includes a controller 192 that is 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 circuitry 194, and a memory 195 that contains 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 one or more operations to be performed using one or more of the components of the substrate processing chamber system 101. The controller 192 may include any form of general-purpose computer processor that can be used in an industrial environment 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, optical disk drive, hard disk, or any other form of digital storage, local or remote. Various support circuits may be coupled to the CPU 193 for supporting the chamber 100. The controller 192 may be coupled to another controller located near individual chamber components. Bidirectional communication between the controller 192 and the various other components of the chamber 100 is processed via a number of signal lines collectively referred to as a signal bus, some of which are as Figure 1 shown.

[0023] Figure 1 The controller 192 shown is configured to control at least one or more of the gas sources 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 cause, when executed by a processor such as the CPU 193, Figure 2One or more of the operations shown in method 200 are performed. In one example, control software 196 includes a set of computer instructions that, when executed, direct CPU 193 of controller 192 to cause Figure 2 One or more of the operations shown in method 200 are performed.

[0024] Figure 2 FIG. 6 is a schematic illustration of method 200 for adsorbing a substrate in a substrate processing chamber. At operation 201, an adsorption voltage is applied to a pedestal having a substrate disposed on a support surface of the pedestal, and / or radio frequency (RF) energy is supplied to the substrate processing chamber. In one embodiment, combinable with other embodiments, a preselected value for the adsorption voltage is used to apply the adsorption voltage. The preselected value can be obtained based on, for example, specifications of the processing chamber, substrate, pedestal, or electrode, or their materials. The preselected value can be obtained from a previous substrate processing or adsorption operation. In one example, when a new pedestal, chamber, and / or substrate are used in a substrate processing operation, one or more experimental runs are used to obtain the preselected value.

[0025] In optional operation 203, a plasma such as an inert plasma is generated. At optional operation 205, the adsorption voltage is ramped up or down until an impedance shift occurs. Alternatively, the adsorption voltage can be ramped up from the applied voltage to a second larger voltage in order to identify the voltage between the applied voltage and the second larger voltage at which the impedance shift occurs. In one embodiment, combinable with other embodiments, the second larger voltage is a preselected value. An impedance shift is detected at operation 207. The impedance shift indicates that the substrate is adsorbed to the support surface of the pedestal.

[0026] In one embodiment, combinable with other embodiments, the adsorption voltage is ramped up or down in one or more voltage increments until an impedance shift occurs. In one example, the adsorption voltage is ramped up in 50-volt increments, with each increment applied for 5 seconds or longer (such as 10 seconds or longer) to allow the impedance sensor to stabilize until an impedance shift occurs. In one example, the adsorption voltage is ramped down in 100-volt increments, with each increment applied for 5 seconds or longer (such as 10 seconds or longer) until an impedance shift occurs.

[0027] Impedance shift is a shift in impedance of at least a predetermined amount, such as 0.5 ohms or greater. In one embodiment, which may be combined with other embodiments, a first impedance value is measured after applying an adsorption voltage at block 201 for a predetermined period of time, such as 5 seconds or longer (such as 10 seconds or longer). In such an embodiment, the adsorption voltage is ramped at block 205 and a second impedance value is measured after applying the ramped adsorption voltage for another equal or different period of time, such as about 5 seconds or longer (such as 10 seconds or longer). Applying the adsorption 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 the impedance shift. When the increment between the measured impedance values exceeds a predetermined threshold amount, a shift is considered to have occurred. In one example, a shift of 0.5 ohms or greater indicates that the substrate is adsorbed and / or the bending of the substrate is reduced or eliminated. However, it should be noted that other shift values are possible.

[0028] In one embodiment, which may be combined with other embodiments, impedance shift is used to verify that the substrate is adsorbed and / or the bending of the substrate is reduced or eliminated. In such an embodiment, an impedance shift value at block 207 that is less than a target value, such as 0.1 ohms or less, is used to verify that the substrate is adsorbed to the pedestal. In one example, after measuring the impedance shift at block 207, a second impedance shift is measured. If the second impedance shift is equal to or less than the target value, such as 0.1 ohms or less, then it is verified that the substrate is adsorbed to the pedestal. If the second impedance shift is greater than the predetermined target value for confirming adsorption, then the substrate may have become at least partially desorbed from the pedestal.

[0029] Without being bound by theory, it is believed that impedance shift is caused by a change in the charge flow between the substrate and one or more other components of the substrate processing chamber system. For example, adsorbing the substrate can remove the bending of the substrate, causing the substrate to flatten against the support surface of the pedestal, thereby reducing one or more gaps between the substrate and the support surface. Reducing one or more gaps between the substrate and the support surface causes a change in the charge flow between the substrate and one or more other components, such as the pedestal. The change in charge flow causes an impedance shift in one or more components of the substrate processing chamber system.

[0030] In one embodiment, which can be combined with other embodiments, the operation of detecting impedance shift includes measuring the impedance shift. A device such as an impedance detector (e.g., impedance detector 190 described above) can be used to detect and / or measure the impedance shift. In one embodiment, which can be combined with other embodiments, the impedance shift is an impedance shift of a radio frequency (RF) energy generator that supplies RF energy to a substrate processing chamber. It is contemplated by the present disclosure that impedance shift can be detected and / or measured for any component of the substrate processing chamber. At operation 209, the impedance shift is used to determine the precise adsorption voltage. In one embodiment, which can be combined with other embodiments, the precise adsorption voltage is the minimum voltage value that adsorbs the substrate to the support surface of the pedestal, for example, without any bending. In one example, the precise adsorption voltage is the adsorption voltage applied at the instant when the impedance shift occurs. Determining and using the precise adsorption voltage facilitates increasing the likelihood that the substrate will be adsorbed to the support surface of the pedestal in operations involving substrates, chambers, or pedestals with varying characteristics. Adsorbing the substrate facilitates reducing or eliminating bending of the substrate and facilitates reducing the likelihood of arc generation by removing or reducing the gap between the substrate support surface and the back side of the substrate. Reducing the likelihood of arc generation facilitates reducing substrate defects and improving the yield of substrate processing operations. Using the precise adsorption voltage also allows the operator to optionally not use a high adsorption voltage during substrate processing, which can cause damage to the back side of the substrate. Reducing the likelihood of back side damage reduces the likelihood of substrate defects and improves the yield of substrate processing operations.

[0031] In one example, the precise adsorption voltage can be based on the adsorption voltage at the instant of impedance shift, plus an additional voltage amount for ensuring adsorption. For example, the precise adsorption voltage can be equal to the adsorption voltage at the instant of impedance shift, plus 5%, 10%, 15%, 20%, 25%, etc. In such an example, the precise adsorption voltage can be determined for a first substrate or a first batch of substrates and then applied to multiple processing runs. Including the additional voltage amount increases the likelihood that the precise adsorption voltage will facilitate adsorption and increases many of the benefits of processing substrates described herein, without performing method 200 on each individual substrate during processing. It is also contemplated that method 200 can be performed on each substrate during processing such that the precise adsorption voltage is the optimal adsorption voltage for each individual substrate.

[0032] In an alternative embodiment, which may be combined with other embodiments, an accurate adsorption voltage is determined by generating a first image of a first impedance trace (e.g., a plot of impedance values versus time for one or more applied voltages), the first impedance trace being measured when an applied adsorption voltage and / or a ramped adsorption voltage is applied to a substrate for a predetermined period of time (such as 5 seconds or longer). The first image of the first impedance trace is compared with a second image of a second impedance trace, the second impedance trace being measured for the same voltage applied to a different substrate for the same period of time. In one example, the different substrate is a flat silicon substrate that does not include a bend. If the first impedance trace matches the second impedance trace, the voltage applied for the first impedance trace is determined to be the accurate adsorption 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, as discussed above, when using a predetermined amount to determine the accurate adsorption voltage, the first impedance trace that matches the second impedance trace is used to confirm the appropriate voltage value of the accurate adsorption voltage.

[0033] By using impedance offset to determine the accurate adsorption voltage, the accurate adsorption voltage can be determined in real time during substrate processing operations. Substrate processing operations do not need to wait until the deposition process on the substrate is complete in order to inspect the substrate to determine whether the applied adsorption voltage is sufficient. This promotes saving time and cost in substrate processing operations and promotes improving yield.

[0034] At optional operation 211, the applied adsorption voltage is adjusted to the accurate adsorption voltage. Adjusting the applied adsorption voltage to the accurate adsorption voltage for subsequent processing can achieve the benefits regarding the accurate adsorption voltage described herein in a timely and cost-effective manner. The accurate adsorption voltage also allows substrate processing operations to efficiently account for and accommodate the varying characteristics between different substrates. For example, if a new pedestal is used in a substrate processing operation, the pedestal may have a different thermal conductivity compared to the previously used pedestal. Using the accurate adsorption voltage to adjust the applied adsorption voltage allows substrate processing operations to efficiently accommodate the different properties of the new pedestal compared to the previous pedestal. This can be done each time a new pedestal is used. As another example, the accurate adsorption voltage can be used to adjust a preselected value obtained from the specifications for a new pedestal. In one aspect, each time a new pedestal is used in a substrate processing operation, one or more operations of method 200 are performed.

[0035] As another example, if a new substrate is used in a substrate processing chamber, the new substrate may have different bending characteristics compared to the previously processed substrates. Different bending characteristics can involve different adsorption voltages that will eliminate the bend in the substrate. Utilizing the aspects discussed herein, an adsorption voltage can be applied to the substrate that eliminates or alleviates the bend without overdoing it, thereby reducing the likelihood of backside damage.

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

[0037] At optional operation 219, in response to the application of the precise adsorption voltage, the bending of one or more substrates is reduced or eliminated. The one or more substrates of optional operation 219 may include the substrates used in operation 201. The one or more substrates of optional operation 219 may be different from the substrates used in operation 201. The one or more substrates of optional operation 219 may include a second substrate and / or a third substrate different from the substrates used in operation 201.

[0038] At optional operation 221, a deposition process is performed while applying the precise adsorption voltage. For example, one or more process gases and the generated process plasma that deposit a film onto one or more substrates may be used to deposit a film onto one or more substrates.

[0039] At optional operation 223, one or more of the operations 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 of optional operation 223 may include a second substrate and / or a third substrate different from the substrates used in operation 201.

[0040] Method 200 is not limited to Figure 2 the order or number of operations shown, but may include other embodiments that include reordering, repeating, adding, and / or removing one or more of the operations 201, 203, 205, 207, 209, 211, 213, 215, 217, 219, 221, and / or 223.

[0041] Figure 3FIG. 300 is a diagram showing an impedance shift according to one embodiment. Image 300 shows an impedance shift that occurs after the adsorption voltage ramps up. In the illustrated embodiment, a first adsorption voltage (e.g., 550 volts) is applied to the substrate for a predetermined period of time, such as 20 seconds. When the first adsorption voltage is applied, a first impedance trace 301 is generated by measuring the impedance over the entire 20 seconds. After the predetermined period of time has elapsed, a first impedance value 302 is measured. The adsorption voltage is ramped up in predetermined voltage increments (e.g., 50 volts or about 10%) to apply a second adsorption voltage (such as 600 volts) 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, such as 20 seconds. When the second adsorption voltage is applied, a second impedance trace 303 is generated by measuring the impedance over the entire additional 20 seconds. After the second period of time (e.g., 20 seconds) has elapsed, a second impedance value 304 is measured. As shown, the impedance of the second impedance trace 303 is substantially stable after the additional 20 seconds have elapsed. This process is repeated, comparing the stable impedance to the previously stable impedance until an impedance shift of at least one threshold is determined.

[0042] The difference 305 between the second impedance value 304 and the first impedance value 302 of at least the threshold (e.g., 0.5 ohms) indicates that the bending of the substrate is reduced or eliminated. The impedance shift indicates that the second adsorption voltage corresponds to the adsorption voltage when the substrate is adsorbed to the support surface. Therefore, there is no need to over-apply the power for adsorption.

[0043] Note that FIG. 300 is only an example, and other images may be generated or detected. The benefits of the present disclosure include reducing arcing, improving the adsorption of the substrate to the base support surface, reducing backside damage, adapting to changing equipment properties in a timely and efficient manner, increasing the yield, and reducing operating costs. Aspects of the present disclosure include: applying an adsorption voltage to the base; using a preselected value to apply the adsorption voltage to the base; ramping up the adsorption voltage until an impedance shift occurs; detecting the impedance shift; determining the exact adsorption voltage based on the impedance shift; and adjusting the applied adsorption voltage to the exact adsorption voltage.

[0044] It is expected that one or more of these aspects disclosed herein may be combined. In addition, it is expected that one or more of these aspects may include some or all of the aforementioned benefits.

[0045] Although the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the present disclosure may be designed without departing from the basic scope of the present disclosure. The present disclosure also anticipates that one or more aspects of the embodiments described herein may be replaced by one or more of the other aspects described. The scope of the present disclosure is determined by the appended claims.

Claims

1. A method for adsorbing a substrate in a substrate processing chamber, comprising: When a first substrate is disposed on a support surface of a pedestal: Applying a first value of an adsorption voltage to the pedestal; Ramping the adsorption voltage from the first value; Detecting an impedance shift while ramping the adsorption voltage; Determining a corresponding second value of the adsorption voltage when the impedance shift occurs; And Determining a third value of the adsorption voltage based on the impedance shift and the corresponding second value of the adsorption voltage; And When a second substrate is disposed on the support surface of the pedestal, applying the third value of the adsorption voltage to the pedestal.

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

3. The method according to claim 1, wherein detecting the impedance shift includes measuring the impedance shift.

4. The method according to claim 1, further comprising: When applying the third value of the adsorption voltage to the pedestal, a deposition process is performed on the second substrate.

5. The method according to claim 1, wherein ramping the adsorption voltage from the first value includes ramping up the adsorption voltage until the impedance shift occurs.

6. The method according to claim 1, wherein the third value of the adsorption voltage is the minimum voltage value for adsorbing the first substrate to the support surface of the pedestal.

7. The method according to claim 1, wherein the third value of the adsorption voltage reduces the bending of the first substrate.

8. A method for adsorbing a substrate in a substrate processing chamber, comprising: When a first substrate is disposed on a support surface of a pedestal, determining a first value of an adsorption voltage to be applied to the pedestal to adsorb the first substrate to the support surface of the pedestal; And When a second substrate is disposed on the support surface of the pedestal: Applying the first value of the adsorption voltage to the pedestal; Ramping the adsorption voltage from the first value; Detecting an impedance shift while ramping the adsorption voltage; Determining a corresponding second value of the adsorption voltage when the impedance shift occurs; Determining a third value of the adsorption voltage based on the impedance shift and the corresponding second value of the adsorption voltage; And Applying the third value of the adsorption voltage to the pedestal.

9. The method according to claim 8, wherein the impedance shift is an impedance shift of a radio frequency energy generator that supplies radio frequency energy to the substrate processing chamber.

10. The method according to claim 8, wherein detecting the impedance shift includes measuring the impedance shift.

11. The method according to claim 8, further comprising: When applying the third value of the adsorption voltage to the pedestal, a deposition process is performed on the second substrate.

12. The method according to claim 8, wherein ramping the adsorption voltage from the first value includes ramping up the adsorption voltage until the impedance shift occurs.

13. The method according to claim 8, wherein the third value of the adsorption voltage is the minimum voltage value for adsorbing the second substrate to the support surface of the pedestal.

14. The method according to claim 8, wherein the third value of the adsorption voltage reduces the bending of the second substrate.

15. A method for adsorbing one or more substrates in a substrate processing chamber, comprising: obtaining a first value of an adsorption voltage to be applied to a susceptor installed in the substrate processing chamber so as to adsorb a first substrate to a support surface of the susceptor; and when the first substrate is disposed on the support surface of the susceptor: applying the first value of the adsorption voltage to the susceptor; ramping the adsorption voltage from the first value; detecting an impedance shift while ramping the adsorption voltage; determining a corresponding second value of the adsorption voltage at which the impedance shift occurs; and determining a third value of the adsorption voltage based on the impedance shift and the corresponding second value of the adsorption voltage.

16. The method according to claim 15, further comprising: When a second substrate is disposed on the support surface of the susceptor, applying the third value of the adsorption voltage to the susceptor.

17. The method according to claim 16, further comprising: Performing a deposition process on the second substrate while applying the third value of the adsorption voltage to the susceptor.

18. The method according to claim 17, further comprising: Generating a plasma while performing the deposition process on the second substrate.

19. The method according to claim 15, wherein the third value of the adsorption voltage is equal to the second value of the adsorption voltage plus 25% or less.

20. The method according to claim 19, further comprising: Storing the third value of the adsorption voltage in a memory of a controller of the substrate processing chamber.

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