Abstract: A method and apparatus for compensating a bias voltage at the wafer by measuring RF voltage signals in RF driven plasma including at least an electrostatic, chuck (ESC), a capacitive divider, a signal processing and signal conditioning network is disclosed. The bias compensation device includes a capacitive divider to detect the RF voltage at the ESC, a signal conditioning network for the purpose of filtering specific RF signals of interests, and a signal processing unit for computing the DC wafer potential from the filtered RF signals.

Abstract: Methods and systems for detecting a change in the state of plasma confinement within a capacitively coupled RF driven plasma processing chamber are disclosed. In one or more embodiments, the plasma unconfinement detection methods employ an analog or digital circuit that can actively poll the RF voltage at the powered electrode in the form of an Electrostatic Chuck (ESC) as well as the open loop response of the power supply (PSU) responsible for chucking a wafer to ESC. The circuit provides a means detecting both a change in RF voltage delivered to the ESC as well as a change in the open loop response of the PSU. By simultaneously monitoring these electrical signals, the disclosed algorithm can detect when plasma changes from a confined to an unconfined state.

Abstract: Systems and methods for soft pulsing are described. One of the systems includes a master radiofrequency (RF) generator for generating a first portion of a master RF signal during a first state and a second portion of the master RF signal during a second state. The master RF signal is a sinusoidal signal. The system further includes an impedance matching circuit coupled to the master RF generator via an RF cable to modify the master RF signal to generate a modified RF signal and a plasma chamber coupled to the impedance matching circuit via an RF transmission line. The plasma chamber is used for generating plasma based on the modified RF signal.

Abstract: Systems and methods for using variables based on a state associated with a plasma system. A method includes determining whether the state associated with the plasma system is a first state or a second state and determining a first variable upon determining that the state is the first state. The first variable is determined based on a measurement at a communication medium. The method further includes determining a second variable upon determining that the state is the second state. The second variable is determined based on a measurement at the communication medium. The method includes determining whether the second variable exceeds a first threshold, providing an instruction to reduce power supplied to a plasma chamber upon determining that the second variable exceeds the first threshold, and providing an instruction to increase power supplied to the plasma chamber upon determining that the second variable is below the first threshold.

Abstract: A method for optimizing a dechuck sequence, which includes removing a substrate from a lower electrode. The method includes performing an initial analysis to determine if a first set of electrical characteristic data of a plasma formed during the dechuck sequence traverses a threshold values. If so, turning off the inert gas. The method also includes raising the lifter pins slightly from the lower electrode to move the substrate in an upward direction. The method further includes performing a mechanical and electrical analysis, which includes comparing a first set of mechanical data, which includes an amount of force exerted by the lifter pins, against a threshold value. The mechanical and electrical analysis also includes comparing a second set of electrical characteristic data against a threshold value. If both traverse the respective threshold value, removes the substrate from the lower electrode since a substrate-released event has occurred.

Abstract: Systems and methods for determining ion energy are described. One of the methods includes detecting output of a generator to identify a generator output complex voltage and current (V&I). The generator is coupled to an impedance matching circuit and the impedance matching circuit is coupled to an electrostatic chuck (ESC). The method further includes determining from the generator output complex V&I a projected complex V&I at a point along a path between an output of a model of the impedance matching circuit and a model of the ESC. The operation of determining of the projected complex V&I is performed using a model for at least part of the path. The method includes applying the projected complex V&I as an input to a function to map the projected complex V&I to a wafer bias value at the ESC model and determining an ion energy from the wafer bias value.

Abstract: Systems and methods for segmenting an impedance matching model are described. One of the methods includes receiving the impedance matching model. The impedance matching model represents an impedance matching circuit, which is coupled to an RF generator via an RF cable and to a plasma chamber via an RF transmission line. The method further includes segmenting the impedance matching model into two or more modules of a first set. Each module includes a series circuit and a shunt circuit. The shunt circuit is coupled to the series circuit. The series circuit of the first module is coupled to a cable model and the series circuit of the second module is coupled to an RF transmission model. The series circuit and the shunt circuit of the first module are coupled to the series circuit of the second module. The shunt circuit of the second module is coupled to the RF transmission model.

Abstract: Systems and methods for determining a malfunctioning device in a plasma system, are described. One of the methods includes receiving an indication whether plasma is generated within a plasma chamber of the plasma system. The plasma system includes a processing portion and a power delivery portion. The method further includes determining whether the plasma system operates within constraints in response to receiving the indication that the plasma is generated, determining a value of a variable at an output of the power delivery portion when the processing portion is decoupled from the power delivery portion, and comparing the determined value with a pre-recorded value of the variable. The method includes determining whether the determined value is outside a range of the pre-recorded value and determining that the malfunctioning device within the power delivery portion upon determining that the determined value is outside the range of the pre-recorded value.

Abstract: Systems and methods for determining wafer bias are described. One of the methods includes detecting output of a generator to identify a generator output complex voltage and current (V&I). The generator is coupled to an impedance matching circuit and the impedance matching circuit is coupled to an electrostatic chuck (ESC). The method further includes determining from the generator output complex V&I a projected complex V&I at a point along a path between an output of a model of the impedance matching circuit and a model of the ESC. The operation of determining of the projected complex V&I is performed using a model for at least part of the path. The method includes applying the projected complex V&I as an input to a function to map the projected complex V&I to a wafer bias value at the ESC model.

Abstract: Systems and methods for tuning a parameter associated with plasma impedance are described. One of the methods includes receiving information to determine a variable. The information is measured at a transmission line and is measured when the parameter has a first value. The transmission line is used to provide power to a plasma chamber. The method further includes determining whether the variable is at a local minima and providing the first value to tune the impedance matching circuit upon determining that the variable is at the local minima. The method includes changing the first value to a second value of the parameter upon determining that the variable is not at the local minima and determining whether the variable is at a local minima when the parameter has the second value.

Abstract: A method for achieving an etch rate is described. The method includes receiving a calculated variable associated with processing a work piece in a plasma chamber. The method further includes propagating the calculated variable through a model to generate a value of the calculated variable at an output of the model, identifying a calculated processing rate associated with the value, and identifying based on the calculated processing rate a pre-determined processing rate. The method also includes identifying a pre-determined variable to be achieved at the output based on the pre-determined processing rate and identifying a characteristics associated with a real and imaginary portions of the pre-determined variable. The method includes controlling variable circuit components to achieve the characteristics to further achieve the pre-determined variable.

Abstract: A bus interconnect interfaces a host system to a radio frequency (RF) generator that is coupled to a plasma chamber. The bus interconnect includes a first set of host ports, which are used to provide a power component setting and a frequency component setting to the RF generator. The ports of the first set of host ports are used to receive distinct variables that change over time. The bus interconnect further includes a second set of generator ports used to send a power read back value and a frequency read back value to the host system. The bus interconnect includes a sampler circuit integrated with the host system. The sampler circuit is configured to sample signals at the ports of the first set at selected clock edges to capture operating state data of the plasma chamber and the RF generator.

Abstract: Systems and methods for determining a value of a variable on a radio frequency (RF) transmission model are described. One of the methods includes identifying a complex voltage and current measured at an output of an RF generator and generating an impedance matching model based on electrical components defined in an impedance matching circuit coupled to the RF generator. The method further includes propagating the complex voltage and current through the one or more elements from the input of the impedance matching model and through one or more elements of an RF transmission model portion that is coupled to the impedance matching model to determine a complex voltage and current at the output of the RF transmission model portion.

Abstract: Systems and methods for statistical data decimation are described. The method includes receiving a variable from a radio frequency (RF) system, propagating the variable through a model of the RF system, and counting an output of the model for the variable to generate a count. The method further includes determining whether the count meets a count threshold, generating a statistical value of the variable at the output of the model upon determining that the count meets the count threshold, and sending the statistical value to the RF system to adjust the variable.

Abstract: Systems and methods for performing edge ramping are described. A system includes a base RF generator for generating a first RF signal. The first RF signal transitions from one state to another. The transition from one state to another of the first RF signal results in a change in plasma impedance. The system further includes a secondary RF generator for generating a second RF signal. The second RF signal transitions from one state to another to stabilize the change in the plasma impedance. The system includes a controller coupled to the secondary RF generator. The controller is used for providing parameter values to the secondary RF generator to perform edge ramping of the second RF signal when the second RF signal transitions from one state to another.

Abstract: Systems and methods for adjusting power and frequency based on three or more states are described. One of the methods includes receiving a pulsed signal having multiple states. The pulsed signal is received by multiple radio frequency (RF) generators. When the pulsed signal having a first state is received, an RF signal having a pre-set power level is generated by a first RF generator and an RF signal having a pre-set power level is generated by a second RF generator. Moreover, when the pulsed signal having a second state is received, RF signals having pre-set power levels are generated by the first and second RF generators. Furthermore, when the pulsed signal having a third state is received, RF signals having pre-set power levels are generated by the first and second RF generators.

Abstract: An arrangement for controlling a plasma processing system is provided. The arrangement includes an RF sensing mechanism for obtaining an RF voltage signal. The arrangement also includes a high impedance arrangement coupled to the RF sensing mechanism to facilitate acquisition of the signal while reducing perturbation of RF power driving a plasma in the plasma processing system. The arrangement further includes a signal processing arrangement configured for receiving the signal, processing the signal in a digital domain to obtain peak voltage information for a fundamental frequency and a broadband frequency of the signal, deriving wafer bias information from the peak voltage information, and applying signal to a transfer function to obtain a transfer function output. The arrangement moreover includes an ESC power supply subsystem configured to receive the transfer function output as a feedback signal to control the plasma processing system.

Abstract: Systems and methods for impedance-based adjustment of power and frequency are described. A system includes a plasma chamber for containing plasma. The plasma chamber includes an electrode. The system includes a driver and amplifier coupled to the plasma chamber for providing a radio frequency (RF) signal to the electrode. The driver and amplifier is coupled to the plasma chamber via a transmission line. The system further includes a selector coupled to the driver and amplifier, a first auto frequency control (AFC) coupled to the selector, and a second AFC coupled to the selector. The selector is configured to select the first AFC or the second AFC based on values of current and voltage sensed on the transmission line.

Abstract: Methods and apparatus for processing a substrate in a multi-frequency plasma processing chamber are disclosed. The base RF signal pulses between a high power level and a low power level. Each of the non-base RF generators, responsive to a control signal, proactively switches between a first predefined power level and a second predefined power level as the base RF signal pulses. Alternatively or additionally, each of the non-base RF generators, responsive to a control signal, proactively switches between a first predefined RF frequency and a second predefined RF frequency as the base RF signal pulses. Techniques are disclosed for ascertaining in advance of production time the first and second predefined power levels and/or the first and second predefined RF frequencies for the non-base RF signals.

Abstract: A synchronized pulsing arrangement for providing at least two synchronized pulsing RF signals to a plasma processing chamber of a plasma processing system is provided. The arrangement includes a first RF generator for providing a first RF signal. The first RF signal is provided to the plasma processing chamber to energize a plasma therein, the first RF signal representing a pulsing RF signal. The arrangement also includes a second RF generator for providing a second RF signal to the plasma processing chamber. The second RF generator has a sensor subsystem for detecting values of at least one parameter associated with the plasma processing chamber that reflects whether the first RF signal is pulsed high or pulsed low and a pulse controlling subsystem for pulsing the second RF signal responsive to the detecting the values of at least one parameter.