WO2011031590A2 - Methods and arrangement for plasma dechuck optimization based on coupling of plasma signaling to substrate position and potential - Google Patents
Methods and arrangement for plasma dechuck optimization based on coupling of plasma signaling to substrate position and potential Download PDFInfo
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- WO2011031590A2 WO2011031590A2 PCT/US2010/047382 US2010047382W WO2011031590A2 WO 2011031590 A2 WO2011031590 A2 WO 2011031590A2 US 2010047382 W US2010047382 W US 2010047382W WO 2011031590 A2 WO2011031590 A2 WO 2011031590A2
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- 239000011261 inert gas Substances 0.000 claims abstract description 38
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Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
- H01L21/683—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for supporting or gripping
- H01L21/6831—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for supporting or gripping using electrostatic chucks
- H01L21/6833—Details of electrostatic chucks
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
- H01J37/32—Gas-filled discharge tubes
- H01J37/32009—Arrangements for generation of plasma specially adapted for examination or treatment of objects, e.g. plasma sources
- H01J37/32082—Radio frequency generated discharge
- H01J37/32091—Radio frequency generated discharge the radio frequency energy being capacitively coupled to the plasma
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
- H01J37/32—Gas-filled discharge tubes
- H01J37/32917—Plasma diagnostics
- H01J37/32935—Monitoring and controlling tubes by information coming from the object and/or discharge
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
- H01L21/683—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for supporting or gripping
- H01L21/687—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for supporting or gripping using mechanical means, e.g. chucks, clamps or pinches
Definitions
- a subsirate is usually clamped to a lower electrode (such as an electrostatic chuck). Clamping may be performed by applying a direct current (DC) potential to the lower electrode to create an electrostatic charge between the substrate and the lower electrode.
- DC direct current
- an inert gas such as helium
- helium may be applied through various channels in the lower electrode to the backside of the substrate to improve the thermal heat transfer between the substrate and the lower electrode. Consequently, due to the helium pressure on the substrate, a relatively high electrostatic charge is required to clamp the substrate to the lower electrode.
- a dechuek sequence is performed in which the clamping voltage is turn off. Even though the clamping voltage is set to zero, a residual electrostatic force remains due to the electrostatic charge between the substrate and the lower electrode.
- a low density plasma may be generated to neutralize the attraction force between the substrate and the lower electrode.
- lifter pins disposed within the lower electrode may be raised to l ift the substrate upward to separate the substrate from the surface of the lower electrode, thereby allowing a robot arm to remove the substrate from the plasma processing chamber.
- a small voltage biased in the opposite charge of the clamping voltage may be applied to the lower electrode to facilitate dechucking.
- the clamp voltage is 10 volts
- a voltage charge of - ⁇ volt may be applied to the lower electrode during the dechuck sequence.
- the application of a clamped voltage in the opposite charge causes the positive charge to flow toward the negative charge to aid in the neutralization of the elec trostatic force between the substrate and the lower electrode.
- the time period for executing a successful dechuck sequence may vary. Since the application time period is unknown beforehand and the consequences for improper dechucking are severe, the tendency is to apply the dechuck sequence for a conservatively long specified time period in order to ensure that there is sufficient time for the electrostatic charge to be sufficiently discharged. Unfortunately, both methods of dechucking (at zero volts and at a bias voltage of reverse polarity) still do not al ways provide a safe and efficient manner of releasing the substrate.
- the electrostatic charge may be such that only a .minimal amoun t of time is required to discharge.
- the specified time period method does not provi de an early-detection method for identifying when the substrate may be safely removed from the lower electrode.
- throughput is negatively impacted as time is wasted while the unhinged substrate remains in the processing chamber for the entire specified time period before the unhinged substrate may he removed from the chamber.
- the existence of the dechuck plasma in the processing chamber for the additional (and unnecessary) time may also contribute to the premature degradation of the chamber components and/or unwanted etching of the substrate.
- the electrostatic charge may not ha ve been sufficiently discharged after the specified time period has elapsed.
- the attempt to remove the hinged substrate may cause the substra te to break.
- the remaining residual electrostatic charge on the substrate may cause the pneumatic lift mechanism to exert a large force on the lifter pins in order to separate the substrate from the lower electrode. Accordingly, the force exerted on the substrate may cause the substrate to shift away from the process center, thereby causing the substrate to be iinproperiy aligned for the next recipe step.
- the residual electrostatic charge on the substrate may cause arcing between the substrate and the robot arm, thereby causing damage to the devices on the substrate and/or the robot arm.
- the electrostatic charge is considered to be discharged. Likewise, if the lifting pin force falls below a predetermined threshold value, the substrate is considered to be sufficiently discharged. However, if any of the threshold values is not traversed, then the electrostatic charge is deemed to have been insufficiently discharged and the mechanical forces and/or the bias voltage/current in the opposite charge may be adjusted,
- one of the mechanical values indicates that a predetermined threshold value (the value that has been designated at which the substrate may be safely released from the lower electrode) has been traversed; however; the electrostatic charge may be nonuniform across the surface of the substrate.
- a predetermined threshold value the value that has been designated at which the substrate may be safely released from the lower electrode
- the electrostatic charge may be nonuniform across the surface of the substrate.
- isolated pockets may exist in which the electrostatic charge has not been sufficiently removed.
- isolated hinging may still occurs resulting in damage to the substrate when the substrate is separated from the lower electrode.
- the invention relates, in an embodiment, to a method for optimizing a dechuck sequence, which includes mechanically removing a substrate from a lower electrode in a processing chamber of a plasma processing system.
- the method includes performing an initial analysis.
- the initial analysis includes analyzing a first set of electrical characteristic data of a plasma, wherein the plasma is formed over the substrate during the dechuck sequence.
- the initial analysis also includes comparing the first set of electrical characteristic data aaainst a set of electrical characteristic threshold values.
- the initial analysis further includes, if the first set of electrical characteristic data traverses the set of electrical characteristic threshold values, turning off inert gas.
- the method also includes raising the lifter pins from the lower electrode to move the substrate in an upward direction, wherein the lifter pins are not raised to a maximum height.
- the method further includes performing a mechanical and electrical analysis.
- the mechanical and electrical analysis includes analyzing a first set of mechanical data, wherein the set of mechanical data includes an amount of force exerted by the lifter pins.
- the mechanical and electrical analysis also includes analyzing a second set of electrical characteristic data.
- the mechanical and electrical analysis further includes comparing the first set of mechanical data to a set of mechanical threshold values and the second set of electrical characteristic data to the set of electrical character istic threshold values.
- the mechanical and electrical analysis yet also includes, if the first set of mechanical da ta traverses the set of mechanical threshold values and the second set of electrical characteristic data traverses the set of electrical characteristic threshold values, removing the substrate from the lower electrode since a substrate-released event has occurred.
- FIG. 1 shows, in an embodiment of the invention, a simple logical block diagram of a processing envi ronment wi th an optimizing dechuck control scheme.
- FIG. 2 shows, in one embodiment of the invention, a simple flow chart for optimizing the dechuck control sequence.
- FIG. 3 shows, in an embodiment of the invention, a simple plasma impedance plot.
- FIG. 4 shows, in an embodiment of the invention, a plot illustrating the relationship between a substrate potential and a bias voltage/current of a lower electrode when lifter pins are at full height.
- Figs. 5A and SB show, in embodiments of the invention, comparison between substrate potential and plasma impedance when the lifter pins are extended to full height.
- Figs, 6 A and 6B show, in embodiments of the invention, comparisons between bias voltage and plasma impedance.
- Fig. 7 shows, in an embodiment of the invention, simple resistance curves for each bias voltage set point.
- FIG. 8 shows, in an embodiment of the invention, a comparison between three dechuck sequences.
- Fig. 9 shows, in an embodiment of the invention, a plot illustrate the relationship between substrate movement and electrical parameters.
- the invention might also cover articles of manufacture that includes a computer readable medium on which computer-readable instructions for carrying out embodiments of the inventive technique are stored.
- the computer readable medium may include, for example, semiconductor, magnetic, opto- magnetic, optical , or other forms of computer readable medium for storing computer readable code.
- the invention may also cover apparatuses for practicing embodiments of the invention. Such apparatus may include circuits, dedicated and/or programmable, to cany out tasks pertaining to embodiments of the invention. Examples of such apparatus include a general-purpose computer and/or a dedicated computing device when appropriately programmed and may include a combination of a computer/computing device and dedicated programmable circuits adapted for the various tasks pertaining to embodiments of the mvention.
- Embodiments of the invention include monitoring electrical signals and mechanical forces to determine when the substrate may be safely separated from the lower electrode. Embodiments of the invention also incorporate both electrical and mechanical forces to facilita te the dissipation of the electrostatic charges between the substrate and the lower electrode. Embodiments of the invention further include methods for identifying conditions for applying corrective actions to facilitate a successful substrate-release event.
- a dechuck sequence is initiated. Unlike the prior art, the dechuck sequence is not performed for a specified time period. Also, unlike the prior art, the separation of the substrate from the lower electrode is not dependent only upon feedbacks from mechanical forces (such as inert gas flow, inert gas pressure, and lifting pin force). Instead, the dechuck sequence is aided by monitoring both mechanical and electrical parameters.
- the parameters include mechanical forces (such as inert gas flow, inert gas pressure, and lifting pin force), electrical parameters that drive the plasma and electrical parameters applied to the lower electrode.
- the monitoring of the mechanical forces and the electrical signals are performed in a continuum. Accordingly, problems (such as localized hinging of the substrate to the lower electrode) that may arise during the dechuck sequence may be identified and appropriate corrective actions may he applied to correct the problems.
- FIG. I shows, in an embodiment of the invention, a simple logical block diagram of a processing environment with an optimized dechuck control scheme.
- a plasma processing system 102 includes a generator source 104, which is configured to provide power to a processing chamber 108 via a matching network 110.
- Processing chamber 108 may include an electrostatic chuck 120 (i.e.. lower electrode). During substrate processing, a substrate (not shown) is typically clamped to electrostatic chuck 120. Clamping may be performed by applying direct current (DC) potential via a DC supply source 122 to create an electrostatic charge between the substrate and electrostatic chuck 120. To improve the thermal conduction between the substrate and electrostatic chuck 120, an inert gas (such as helium) is applied to the backside of the substrate through various channels (not shown) in electrostatic chuck 120. Thus, clamping is an important component of substrate temperature control since proper clamping permits helium cooling of the backside of the substrate to be proper ly controlled. However, due to the induced pressure caused by the inert gas, a relatively high clamp voltage is required to create a sufficiently strong attraction force between the substrate and electrostatic chuck 120.
- DC direct current
- a dechuck sequence may be executed to discharge the electrostatic charae between the substrate and electrostatic chuck 120.
- the dechuck sequence includes turning off the clamping voltage and generating a low-powered plasma to neutralize the electrostatic charge without etching the substrate.
- the monitoring method includes observing mechanical parameters (such as helium flow, induced pressure, force exerted by the lifter pins, and the likes) that may affect the separation of the substrate from electrostatic chuck 120.
- mechanical parameters such as helium flow, induced pressure, and lifter pin force
- the mechanical parameters do not accurately characterize the electrostatic forces between the substrate and electrostatic chuck 120.
- methods are provided for monitoring electrical parameters (in addition to the mechanical parameters) that may provide insights into one or more characteristics (substrate movement relative to electrostatic chuck .120, electrostatic charge spatial uniformity, and substrate potential) of the electrostatic charge. Also, unlike the prior art, the parameters are measured on a continuum to identify not only when the electrostatic charge has been sufficiently discharged but to identify when corrective actions are required to be applied to faci litate the dechuck sequence.
- a tool controller 124 may be receiving processing data from a plurality of sources. As can be appreciated, the processing data may be either in an analog or a digital format. In an embodiment, tool controller 124 may be receiving voltage and current data from a sensor i 12. With the voltage and current data, plasma impedance may be determined. The plasma impedance is monitored since the piasma impedance reflects the electrical characteristic of the plasma when physical perturbations in the substrate cause oscillations in the plasma. The physical perturbations may be due to the main electrostatic force being removed.
- tool controller 124 may also be receiving data about inert gas (e.g., helium) flow between the substrate and electrostatic chuck 120 from an inert, gas controller 126. Too! controller 124 may also be receiving data about the lifter pin height from the pneumatic lifter pin assembly 128. Additionally, tool controller 124 may be recei ving data about bias voltage/ current from DC supply source 122.
- inert gas e.g., helium
- tool controller 124 is able to monitor the parameters on a continuum basis, in an embodiment, the data collected may be analyzed in order to determine when the substrate can be lifted from electrostatic chuck 120 and remove from processing chamber 108. Additionally or alternatively, the data collected may be analyzed in order to determine when corrective actions may be required, in an example, the electrostatic charge across the surface of the substrate may not be uniformed. In an embodiment, tool controller 124 may instruct DC supply source 122. to apply additional bias voltage/current in the opposite charge to one or more pole of electrostatic chuck 120 in order to facilitate the neutralization of electrostatic charge in the localized region that may not have been sufficiently discharged. In another example, if additional inert gas pressure is required based on the data being analyzed, additional inert gas pressure may be applied to unhinge the substrate from electrostatic chuck 120.
- Fig. 2 shows, in one embodiment of the invention, a simple flow chart for optimizing the dechuck control sequence.
- a first step 202 substrate processing is completed.
- the substrate is being etched within processing chamber 108. Once the main etch has been completed, the substrate is ready to be dechucked and removed from processing chamber 108, To begin the dechuck sequence, the power (such as the power being provided by generator source 104) is ramped down. Accordingly, a low-powered plasma may be formed to neutralize the electrostatic charge on the substrate.
- the processing chamber is vacated (wafer backside inert gas).
- the high pressure of about 20-30 torrs, in one example
- the high pressure employed during substrate processing is pumped out of processing chamber 108.
- the clamp voltage is turned off.
- the clamp voltage is the DC potential that is applied by DC supply source 122 to electrostatic chuck 120 to create the electrostatic charge on the substrate. By turning off the clamp voltage the DC potential is set to zero.
- the backside inert gas flow is applied to the substrate.
- inert gas such as helium
- clamp voltage may be applied to electrostatic chuck 120 to clamp the substrate to electrostatic chuck 320.
- FIG. 47 When the clamp voltage is turned off, the substrate may flex back to its natural state. The flexing of the substrate may cause an oscillation in the plasma which may be reflected in the change to the electrical characteristic of the plasma.
- a simple plasma impedance plot is provided, in an embodiment.
- Plot line 302 shows the plasma impedance after the clamp voltage has been turned off.
- point 304 a perturbation is shown in the plasma impedance of the plasma when the DC potential is set to zero.
- the substrate when the clamp voltage is turned off, the substrate may flex as it returns to its natural state.
- the flexing of the substrate mav cause an oscillation into the plasma that may translate as a change in the electrical characteristic of the plasma (such as plasma impedance).
- the plasma impedance may not. show any change, in an example, if a relatively high electrostatic charge is required to clamp the substrate to electrostatic chuck 120 during substrate processing, the removal of the clamp voltage may not cause a perturbation in the plasma impedance given that a high residual electrostatic charge may remain (as shown by plot line 306). Accordingly; embodiments of the invention provide for monitoring and analysis of more than one electrical parameter to remove the potential for false positives.
- one or more electrical parameter is analyzed.
- electrical parameters include plasma impedance, DC bias
- the data about the electrical parameters may be captured by sensor 112 ⁇ such as a voltage current probe) and sent to tool controller 124 for analysis.
- the processing data is compared against a set of threshold values, if the processing data does not tra verse a set of threshold values, the electrostatic charge is not considered to be sufficiently discharged, hi an embodiment, a single electrical parameter (such as plasma impedance) may be compared to a predetermined threshold value. In another example, a combination of electrical parameters may be compared to a set of threshold values. As can be appreciated from the foregoing, comparison criteria may he established in which certam combinations of electrical signatures have to be traversed before the electrostatic charge is considered to be successfully discharged,
- the term traverse may include exceed, fall bellow, be within range, and the like.
- the meaning of the word traverse may depend upon the requirement of the threshold value/range.
- the processing data is considered to ha ve tra versed the threshold value/range if the plasma impedance value has met or exceed the threshold val ue/range.
- the recipe requires the plasma impedance, for example, to be below a value, then the processing data has traversed the threshold value/range if the plasma impedance value has fallen below the threshold value/range.
- a time check refers to the amount of time allowed by a recipe for the dechuck sequence. Since each recipe may differ, the time threshold value may vary with each recipe. In an example, if the dechuck sequence for recipe 1 is allotted 5 seconds, then the threshold value may be set to 3 seconds. However, if the dechuck sequence for recipe 2 is allotted 10 seconds, then the threshold value may be set to a higher threshold. As can be appreciated from the foregoing, the threshold values may be theoretically or empirically calculated.
- the inert gas parameter is adjusted, in an embodiment, in an example, the gas pressure may he increased.
- the system may return to step 210 to analyze the recently collected electrical parameter processing data, in an embodiment, if the inert gas pressure and/or gas flow is beyond a predetermined threshold val e, then the inert gas pressure/flow is not adjusted given that too much adjustment in the inert gas pressure/flow may result in an uncontrolled dechuck event thai may damage the substrate and/or chamber components.
- a next step 220 the force exerted is measured and compared against a threshold value.
- a threshold value an indicator that the eiectrostatic charge has been sufficiently discharged Co safely remove the substrate.
- a single electrical parameter such as plasma impedance
- a threshold value such as a threshold value
- a combination of electrical parameters such as plasma impedance and generator power is compared again st a set of threshold values.
- corrective actions may be performed at a next step 228. Corrective actions may include increasing the inert gas pressure. Note that if the inert gas pressure has already reached a predetermined threshold, additional pressure is not applied. Another corrective action may include increasing the force on the lifter pins. Yet another corrective action may include applying a bias voltage/current of reverse polarity to lower electrode 108.
- the corrective action ins tead of applying the corrective action uniformly across the surface of the substrate, the corrective action may be applied locally. In other words, if isoiated regions of the substrate are still hinged to lower electrode, the correcti ve action may be applied to that isolated regions.
- electrostatic chuck 120 may be a bipolar electrostatic chuck. The processing data indicates that the substrate region around pole 1 still have to much residual electrostatic charge. Thus, a higher bias voltage/current in the opposite charge may be applied to pole 1 to facilitate in the neutralization of the electrostatic charge in that area.
- the method of selectively applying corrective action substantially minimizes the possibility of the substrate being exposed to unnecessary processing.
- Steps 220 through 228 are iterative until the comparison (step 224) indicates that the set. of threshold values has been traversed and that the substrate may be safely separated from the lower electrode ⁇ step 230) or time has run out ⁇ at step 226),
- emergency procedures may be implemented.
- Emergency procedures may vary depending upon the recipe.
- an emergency procedure may include sending an alarm notification about the pending dechucking problem, in another e ample ; human intervention may be required to resolve the dechucking problem.
- the emergency procedure may include exerting a high amount of force by the pneumatic lift mechanism to separate the substrate from the lower electrode in order to remove the substrate from the processing chamber.
- the requirement for certain emergency procedures may also be an indication that chamber maintenance may be required to reset the chamber,
- the innovative methods provide an optimization dechucking control scheme.
- the optimal time for a substrate-release event is not only identified but may also be aided. Accordingly, unlike the prior art, time is not wasted while the unhinged substrate remains in the processing chamber for a specified time period. Further, the potential for false positive is substantially eliminated since the substrate-release event is based on mechanical values and electrical characteristics of the plasma, in addition, the dechuck sequence may be aided by adj usting certain mechanical and/or electrical parameters if the dechuck sequence is not proceeding in a timely manner.
- Fig. 4 shows, in an embodiment of the invention, a plot 402 illustrating the relationship between the substrate potential and the bias voltage current of the lower electrode when the lifter pins are at full height.
- Figs. 5A and S B show, in embodiments of the invention, comparison between substrate potential and plasma impedance when the lifter pins are extended to full height.
- the plots show thai the substrate with no impedance signal has a higher substrate potential (plot 306 from Figure 3 correlates to Fig. 5B) than the substrate with an impedance signal (plot 302 from Figure 3 correlates to Fig. 5.4).
- the substrate in plot 306 has a higher residual electrostatic charge then the substrate in plot 302 when the substrate has been separated from the lower electrode.
- the substrate with the higher potential may not dechuck. properly.
- Figs. 6A and 6B show, in embodiments of the invention, comparisons between bias voltage and plasma impedance.
- a bias supply either voltage or current
- the electrostatic force between a substrate and a lower electrode is reduced.
- the clamp voltage applied to create an electrostatic charge between the substrate and the lower electrode during substrate processing has a positive charge.
- the electrostatic force is reduced, thereby enabling the substrate to exhibit physical perturbations.
- the physical perturbations cause osci llations in the plasma.
- the oscillations are captured as changes to the plasma impedance.
- Plot 602 shows an increase in the bias voltage as a function of time (as shown in Fig. 6A).
- Plot 604 shows the corresponding plasma impedance as a function of time (as shown in Fig, 6B). For each increase in the bias voltage on plot 602, a corresponding perturbation is shown in the plasma impedance on plot 604. Thus, the change in the bias voltage has a corresponding change in the plasma impedance.
- Fig. 7 shows, in an embodiment, simple resistance curves for each bias voltage set point.
- Plot 702 shows the resistance curve of an inner pole of the lower electrode and plot 704 shows the resistance curve of an outer pole. As can he seen from the two plots, each pole may require different potential to clamp a substrate to the lower electrode.
- Fig. 8 shows, in an embodiment of the invention, a comparison between three dechuck sequences. Both plots 802 and 804 show a successful separation of the substrate from the lower electrode. However, plot 804 shows a more severe oscillation in the electrical signal (such as plasma impedance). As a result, more force may have been required to facilitate the separation. Thus, the substrate shown in plot 804 may have shifted away from its process center. By knowing the magnitude of the oscillation, corrective action may be taken to correct potential misalignment (for the substrate in plot 804).
- the electrical signal such as plasma impedance
- FIG. 9 shows, in an embodiment of the invention, how substrate movement is reflected in the electrical parameters.
- the electrical signal such as plasma impedance
- the electrical signal changes (as shown in plot 904).
- the plasma impedance changes (as shown in plot 904).
- the plasma impedance changes (as shown in plot 904).
- the helium gas flow is turn off at around 78 seconds (908)
- plasma impedance reflects an oscillation even though the oscillation is comparatively less severe.
Abstract
Description
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Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
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SG2012009627A SG178372A1 (en) | 2009-09-10 | 2010-08-31 | Methods and arrangement for plasma dechuck optimization based on coupling of plasma signaling to substrate position and potential |
JP2012528825A JP5735513B2 (en) | 2009-09-10 | 2010-08-31 | Method and apparatus for plasma dechuck optimization based on coupling of plasma signal to substrate position and substrate potential |
CN201080039844.7A CN102484086B (en) | 2009-09-10 | 2010-08-31 | Methods and arrangement for plasma dechuck optimization based on coupling of plasma signaling to substrate position and potential |
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US12/557,387 | 2009-09-10 | ||
US12/557,381 US20110060442A1 (en) | 2009-09-10 | 2009-09-10 | Methods and arrangement for detecting a wafer-released event within a plasma processing chamber |
US12/557,381 | 2009-09-10 | ||
US12/557,387 US8797705B2 (en) | 2009-09-10 | 2009-09-10 | Methods and arrangement for plasma dechuck optimization based on coupling of plasma signaling to substrate position and potential |
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WO2011031590A2 true WO2011031590A2 (en) | 2011-03-17 |
WO2011031590A3 WO2011031590A3 (en) | 2011-06-30 |
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PCT/US2010/047380 WO2011031589A2 (en) | 2009-09-10 | 2010-08-31 | Methods and arrangement for detecting a wafer-released event within a plasma processing chamber |
PCT/US2010/047382 WO2011031590A2 (en) | 2009-09-10 | 2010-08-31 | Methods and arrangement for plasma dechuck optimization based on coupling of plasma signaling to substrate position and potential |
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KR (2) | KR20120073227A (en) |
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US8520360B2 (en) * | 2011-07-19 | 2013-08-27 | Lam Research Corporation | Electrostatic chuck with wafer backside plasma assisted dechuck |
JP6789099B2 (en) * | 2016-12-26 | 2020-11-25 | 東京エレクトロン株式会社 | Measurement method, static elimination method and plasma processing equipment |
US10770257B2 (en) | 2018-07-20 | 2020-09-08 | Asm Ip Holding B.V. | Substrate processing method |
US11437262B2 (en) | 2018-12-12 | 2022-09-06 | Applied Materials, Inc | Wafer de-chucking detection and arcing prevention |
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Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5459632A (en) * | 1994-03-07 | 1995-10-17 | Applied Materials, Inc. | Releasing a workpiece from an electrostatic chuck |
US6307728B1 (en) * | 2000-01-21 | 2001-10-23 | Applied Materials, Inc. | Method and apparatus for dechucking a workpiece from an electrostatic chuck |
US20030210510A1 (en) * | 2002-05-07 | 2003-11-13 | Hann Thomas C. | Dynamic dechucking |
US20060087793A1 (en) * | 2004-10-21 | 2006-04-27 | Taeg-Kon Kim | Methods adapted for use in semiconductor processing apparatus including electrostatic chuck |
US7196896B2 (en) * | 1998-09-30 | 2007-03-27 | Lam Research Corporation | Dechucking method and apparatus for workpieces in vacuum processors |
Family Cites Families (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3125593B2 (en) * | 1994-09-09 | 2001-01-22 | 株式会社日立製作所 | Electrostatic suction device and method |
JPH10163306A (en) * | 1996-12-04 | 1998-06-19 | Sony Corp | Method and apparatus for manufacturing semiconductor device |
JPH11260897A (en) * | 1998-03-12 | 1999-09-24 | Matsushita Electric Ind Co Ltd | Method and apparatus handling substrate, and vacuum chucking and inspecting method and apparatus used therefor |
US6965506B2 (en) * | 1998-09-30 | 2005-11-15 | Lam Research Corporation | System and method for dechucking a workpiece from an electrostatic chuck |
US7218503B2 (en) * | 1998-09-30 | 2007-05-15 | Lam Research Corporation | Method of determining the correct average bias compensation voltage during a plasma process |
US6570752B2 (en) * | 1999-12-28 | 2003-05-27 | Nikon Corporation | Wafer chucks and the like including substrate-adhesion detection and adhesion correction |
JP2002203837A (en) * | 2000-12-28 | 2002-07-19 | Mitsubishi Electric Corp | Plasma treatment method and apparatus, and manufacturing method of semiconductor device |
JP3702220B2 (en) * | 2001-11-29 | 2005-10-05 | 株式会社東芝 | Plasma management method |
JP4313656B2 (en) * | 2003-11-19 | 2009-08-12 | パナソニック株式会社 | Manufacturing method of semiconductor device |
US20050212450A1 (en) * | 2004-03-16 | 2005-09-29 | Scientific Systems Research Limited | Method and system for detecting electrical arcing in a plasma process powered by an AC source |
JP4884811B2 (en) * | 2006-03-20 | 2012-02-29 | 三菱重工業株式会社 | Glass substrate electrostatic adsorption device and adsorption / desorption method thereof |
KR101394337B1 (en) * | 2006-08-30 | 2014-05-13 | 엘아이지에이디피 주식회사 | Electrostratic Chuck |
JP4646941B2 (en) * | 2007-03-30 | 2011-03-09 | 東京エレクトロン株式会社 | Substrate processing apparatus and method for stabilizing state in processing chamber |
-
2010
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Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5459632A (en) * | 1994-03-07 | 1995-10-17 | Applied Materials, Inc. | Releasing a workpiece from an electrostatic chuck |
US7196896B2 (en) * | 1998-09-30 | 2007-03-27 | Lam Research Corporation | Dechucking method and apparatus for workpieces in vacuum processors |
US6307728B1 (en) * | 2000-01-21 | 2001-10-23 | Applied Materials, Inc. | Method and apparatus for dechucking a workpiece from an electrostatic chuck |
US20030210510A1 (en) * | 2002-05-07 | 2003-11-13 | Hann Thomas C. | Dynamic dechucking |
US20060087793A1 (en) * | 2004-10-21 | 2006-04-27 | Taeg-Kon Kim | Methods adapted for use in semiconductor processing apparatus including electrostatic chuck |
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JP2013504874A (en) | 2013-02-07 |
WO2011031589A3 (en) | 2011-06-03 |
SG178374A1 (en) | 2012-03-29 |
CN102484086B (en) | 2014-10-15 |
KR20120073227A (en) | 2012-07-04 |
CN102598237A (en) | 2012-07-18 |
WO2011031590A3 (en) | 2011-06-30 |
SG178372A1 (en) | 2012-03-29 |
WO2011031589A2 (en) | 2011-03-17 |
KR20120073226A (en) | 2012-07-04 |
JP2013504873A (en) | 2013-02-07 |
SG10201405047VA (en) | 2014-10-30 |
CN102484086A (en) | 2012-05-30 |
JP5735513B2 (en) | 2015-06-17 |
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