KR20150122605A

KR20150122605A - Soft pulsing

Info

Publication number: KR20150122605A
Application number: KR1020150057037A
Authority: KR
Inventors: 주니어 존 씨. 발코어
Original assignee: 램 리써치 코포레이션
Priority date: 2014-04-23
Filing date: 2015-04-23
Publication date: 2015-11-02
Also published as: CN105047513B; TWI677263B; TW201607379A; CN105047513A

Abstract

Disclosed are systems and methods for soft pulsing. One of the systems comprises a master RF generator for generating a first part of a master RF signal during a first state, and generating a second part of the master signal during a second state. The master RF signal is a sine signal. The system further includes an impedance matching circuit coupled with the master RF generator through an RF cable for correcting the master RF signal for generating a corrected RF signal; and a plasma chamber coupled with the impedance matching circuit through an RF transmissive line. The plasma chamber is used for generating plasma based on the corrected RF signal. A statistically measured value of the first part has a positive slope or a negative slope.

Description

SOFT PULSING

A system for etching a material from a wafer or depositing material on a wafer includes a plasma chamber and a generator for generating a radio frequency (RF) signal. The wafer is positioned within the plasma chamber. The generator supplies an RF signal to the plasma chamber to etch the wafer or to deposit materials on the wafer.

Control of etching or deposition increases wafer yield, saves cost, and reduces the time to etch or deposit materials on the wafer. However, it is difficult to control etching or deposition.

The embodiments described in this disclosure occur in this context.

The present invention relates to systems and methods for soft pulsing.

In various embodiments, one of the methods includes reducing the rate of impedance change of the plasma with respect to time, e.g., decreasing dZ / dt, where Z is the plasma impedance and t is the time . The sudden increase or decrease in the impedance change rate causes instability in the plasma, and instability causes a lack of control during the workpiece etching or material deposition on the workpiece. The impedance change rate is reduced by feeding a radio frequency (RF) signal having statistical measurements with a positive slope or negative slope to the plasma chamber. For example, providing an RF signal to the plasma chamber with a root mean square (RMS) value that gradually increases or decreases over a period of time is compared to providing an RF signal with an RMS value that increases or decreases abruptly. The provision of a positive slope or negative slope provides control over changes in the impedance of the plasma. Control over the impedance change enables control over the etching or deposition process.

In some embodiments, a system for soft pulsing includes a master RF generator for generating a first portion of a master RF signal during a first state and a second portion of a master 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 to generate the plasma based on the modified RF signal. The statistical measure of the first part has a positive slope or a negative slope.

In various embodiments, the method includes generating a first portion of the master RF signal during a first state and generating a second portion of the master signal during a second state. The method further includes matching the impedance of the source and the load based on the master RF signal to produce a modified RF signal. The source includes an RF generator and an RF cable. The load includes an RF transmission line and a plasma chamber. The method includes receiving a modified RF signal to produce a plasma in the plasma chamber. The statistical measure of the first part has a positive slope or a negative slope.

In some embodiments, the plasma system includes a first RF generator for generating a first portion of a first RF signal during a first state and a second portion of a first RF signal during a second state. The first RF signal is a sinusoidal signal. The first RF generator is coupled to an impedance matching circuit coupled to the plasma chamber. The statistical measurement of the first portion of the first RF signal has a positive slope or a negative slope.

Some of the advantages of the embodiments described above include controlling the rate of impedance change of the plasma within the plasma chamber. The rate of change is controlled by controlling the slope of the statistical measurement during transition from one state of the digitally pulsed signal to another state of the digitally pulsed signal. The slope is controlled either positive or negative. In some embodiments, the slope is not zero and is at least finite for the time period of the cycle of the digitally pulsed signal. By controlling the tilt, a change in the plasma impedance is controlled to control the etch rate or deposition rate or the processing rate of the processing workpiece.

Other advantages of some embodiments described herein include providing feedback to the processor, e.g., flow rate, pressure, gap, etc., of the parameters associated with the plasma system. The processor determines based on the feedback whether a delay is added to the pulsed signal provided to the RF generator. Feedback is used to synchronize the response times of the mechanical components of the plasma system with the response times of the electrical components of the plasma system.

Other aspects will become apparent from the following detailed description, taken in conjunction with the accompanying drawings.

The various embodiments of the present disclosure may best be understood by reference to the following description taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A illustrates a graph illustrating soft-pulsing of a first variable, in accordance with various embodiments of the present disclosure.
Figure IB illustrates a further graph illustrating soft pulsing of a first variable, according to some embodiments of the present disclosure.
FIG. 1C-1 illustrates a graph illustrating soft-pulsing of a first variable, according to some embodiments of the present disclosure.
FIG. 1C-2 illustrates a graph illustrating soft pulsing of a first variable in synchronization with three states of a pulsed signal, in accordance with some embodiments of the present disclosure.
1D-1 illustrate more graphs illustrating soft-pulsing of a first variable, according to some embodiments of the present disclosure.
1D-2 illustrate more graphs illustrating soft-pulsing of a first variable that is synchronized with the three states of the pulsed signal, in accordance with some embodiments of the present disclosure.
Figure IE illustrates additional graphs illustrating soft-pulsing of a first variable, in accordance with some embodiments of the present disclosure.
Figure 1F depicts graphs illustrating soft-pulsing of a first variable, in accordance with various embodiments of the present disclosure.
Figure 2a illustrates graphs illustrating soft-pulsing of a second variable, in accordance with various embodiments of the present disclosure.
Figure 2B depicts graphs illustrating soft pulsing of a second variable, according to some embodiments of the present disclosure.
FIG. 2C-1 illustrates graphs illustrating soft-pulsing of a second variable, according to some embodiments of the present disclosure.
Figure 2c-2 illustrates graphs illustrating soft pulsing of a second variable in synchronization with the three states of the pulsed signal, in accordance with some embodiments of the present disclosure.
Figure 2d-1 illustrates more graphs illustrating soft-pulsing of a second variable, according to some embodiments of the present disclosure.
Figure 2D-2 shows more graphs illustrating soft pulsing of a second variable in synchronization with the three states of the pulsed signal, in accordance with some embodiments of the present disclosure.
FIG. 2E illustrates additional graphs illustrating soft-pulsing of a second variable, in accordance with some embodiments of the present disclosure.
Figure 2F depicts graphs illustrating soft pulsing of a second variable, in accordance with various embodiments of the present disclosure.
3 is a graph illustrating the graph of each of the graphs of FIGS. 1A-1F and FIGS. 2A-2F, plotting statistical measurements of a sinusoidal signal generated by an RF generator, in accordance with various embodiments of the present disclosure .
FIG. 4 illustrates a flowchart of a method of achieving a first variable as shown in any of the graphs of FIGS. 1A-1F, according to some embodiments of the present disclosure, Lt; RTI ID = 0.0 > RF < / RTI > signal is generated by an RF generator to achieve a second parameter.
Figure 5 illustrates a number of graphs for illustrating similarities between graphs, in accordance with some embodiments of the present disclosure.
6A is a diagram of a plasma system for performing soft pulsing using a digitally pulsed signal from a host system, in accordance with some embodiments of the present disclosure.
6B is a diagram of a plasma system for illustrating the application of soft pulsing to a plurality of variables by using a phase delay circuit and receiving a digitally pulsed signal from a host system, in accordance with some embodiments of the present disclosure.
7 illustrates a master RF generator for generating a digitally pulsed signal and a plasma system for illustrating the use of a phase delay circuit for performing soft pulses, in accordance with various embodiments of the present disclosure.
8 is a diagram of a plasma system for illustrating the use of a feedback system to determine the time to provide the next state of a digitally pulsed signal, in accordance with various embodiments of the present disclosure.
9 is a diagram of a tri-state pulsed signal used to generate tri-states, in accordance with various embodiments of the present disclosure.
Figure 10 is a graph illustrating first and second variables in synchronization with a pulsed signal, in accordance with various embodiments of the present disclosure.

The following embodiments describe systems and methods for performing soft pulsing.

Figure 1a shows an embodiment of graphs (a1, a2, a3, and a4) for illustrating soft pulsing of a first variable, e.g., variable 1, etc. or a first parameter, e.g., parameter 1, / RTI > Each graph of a1 through a4 plots time versus root mean square (RMS) values, examples of first variables. Examples of the first variable include the power of the RF generator, the inverse of this power, the voltage of the RF generator, the current of the RF generator, the inverse of the voltage, the inverse of the current, the frequency of the RF generator, . Examples of the first parameter include the gap between the upper electrode of the plasma chamber and the chuck, the pressure in the plasma chamber, and the flow rate of one or more process gases into the plasma chamber. The top electrode, chuck, plasma chamber, and one or more process gases are described further below.

In some embodiments, the power of the RF generator is the power of the RF signal generated and supplied by the RF generator. In various embodiments, the power of the RF generator is the power of the signal reflected from the plasma chamber toward the RF generator.

In some embodiments, the power of the RF generator is the RF power delivered by the RF generator. For example, the delivered RF power is the difference between the RF power of the RF signal supplied by the RF generator and the RF power of the RF signal reflected back from the plasma chamber toward the RF generator.

In various embodiments, the current of the RF generator is the current of the RF signal generated and supplied by the RF generator. In various embodiments, the current of the RF generator is the current of the signal reflected from the plasma chamber toward the RF generator.

In some embodiments, the current in the RF generator is the current delivered by the RF generator. For example, the delivered current is the difference between the current of the RF signal supplied by the RF generator and the RF signal reflected back from the plasma chamber toward the RF generator.

In some embodiments, the voltage of the RF generator is the voltage of the RF signal generated and supplied by the RF generator. In various embodiments, the voltage of the RF generator is the voltage of the signal reflected from the plasma chamber toward the RF generator.

In some embodiments, the voltage of the RF generator is the voltage delivered by the RF generator. For example, the delivered voltage is the difference between the voltage of the RF signal supplied by the RF generator and the voltage of the RF signal reflected back toward the RF generator from the plasma chamber.

In various embodiments, the frequency of the RF generator is the frequency of the RF signal generated and supplied by the RF generator. In various embodiments, the frequency of the RF generator is the frequency of the signal reflected from the plasma chamber toward the RF generator.

In some embodiments, the frequency of the RF generator is the frequency delivered by the RF generator. For example, the transmitted frequency is the difference between the frequency of the RF signal supplied by the RF generator and the frequency of the RF signal reflected back from the plasma chamber toward the RF generator.

The RMS value has a state S0 and a state S1. State S0 and state S1 periodically recur. Each associated with a combination of the power of the RF generator, the frequency of the RF generator, the current of the RF generator, the voltage of the RF generator, the pressure in the plasma chamber, the gap between the top electrode and the chuck, and the flow rate of one or more process gases in the plasma chamber do. For example, a first combination of frequency, power, pressure, gap, and chemical flow rate is used during state S0 and a second combination of frequency, power, pressure, gap, Is used. In some embodiments, the chemical comprises one or more process gases. To further illustrate, in a first combination, a first frequency value, a power, a pressure, a gap, and a flow rate of a chemical are used, and in a second combination, a second frequency value and a power of the same magnitude as in the first combination, Equal-sized pressures, equal-sized gaps, and the same flow rate of the same chemicals are used. As another example, in a first combination, a first frequency value, a first power value, a pressure, a gap, and a flow rate of a chemical are used, and in a second combination, a second frequency value, a second power value, The same size of pressure as the combination, the same size of gap, and the same flow rate of the same chemicals are used. In some embodiments, the pressure in the plasma chamber is wafer area pressure (WAP).

In various embodiments, state S0 is generated when a clock signal, e.g., a pulsed signal, etc., is pulsed from a high state to a low state, and the clock signal is pulsed from a low state to a high state State S1 is generated. During state S0, the clock signal is in a low state and during state S1, the clock signal is in a high state. In some embodiments, the clock signal has a 50% duty cycle. In various embodiments, the clock signal has a duty cycle other than 50%, e.g., 10%, 20%, 60%, 80%, and so on. For example, state S0 occurs at 10% of the clock cycle, and state S1 occurs during the remaining 90% of the clock cycle. In some embodiments, the clock signal is generated by a clock source, e.g., a crystal oscillator, processor, or the like.

In some embodiments, during state S0, the clock signal is in the high state and during state S1, the clock signal is in the low state.

In some embodiments, instead of RMS values, any other statistical measure, e.g., mean values, or peak-to-peak amplitude, or zero-to-peak amplitude, or median values, And is plotted against time t.

Graph a1 has a constant value, e.g. a set of amplitudes A1, etc. during state S0 and during ramp up ramp up with a negative linear slope to have a set A2 of amplitudes during state < RTI ID = 0.0 & ) And shows a positive sawtooth waveform dropping back to a constant value at the end of state S1. Dropback to constant value is during transition from state S1 to state S0.

In some embodiments, during state S0, a different processing operation than that performed during state S1 is performed on the workpiece. For example, during state S1, the workpiece is etched and during the state SO, the materials are deposited on the workpiece. The workpiece is described further below.

In various embodiments, during state S 1, the ion energy of the plasma in the plasma chamber is greater than the etch rate threshold to maximize the etching of the workpiece during state S 1 and increase the etch rate ratio to the deposition rate. In addition, during state SO, the ion energy of the plasma in the plasma chamber is less than the etch rate threshold to minimize the etching of the workpiece and reduce the etch rate to deposition rate during state SO.

In some embodiments, the occurrence time period of state S1 or state S0 is greater than 5% of the total time period of states S1 and S0.

Referring to graph a2, during state S0, graph a2 has a sine shape with a negative slope during a portion of state S0 and falling to a constant value during the remainder of state S0. In addition, during state S1, graph a2 has a constant value during a portion of state S1 and becomes a sinusoid with a positive slope during the remainder of state S1. Graph a2 is a sine curve except that the sine curve is clamped at the bottom of the sine curve. Graph a2 is clamped during a portion of the occurrence time period of the sinusoid with negative slope and a portion of the occurrence time period of the successive sinusoid with positive slope. In addition, graph a2 has a set of amplitudes A3 during state S0 and a set of amplitudes A4 during state S1.

Graph a3 has a negative linear slope during state S0 and a positive linear slope during state Sl. In addition, graph a3 has a set of amplitudes A5 during state S0 and a set of amplitudes A6 during state S1.

Graph a4 has a zero slope during a portion of state S0 and is clamped to have a negative sinusoidal slope during the remainder of state S0. In addition, graph a4 has a positive sinusoidal slope during a portion of state S1 and is clamped to have a slope of zero during the remainder of state S0. Graph a4 is a sinusoid, except that the sinusoid is clamped at the top of the sinusoid. Graph a4 has a set of amplitudes A7 during state S0 and a set of amplitudes A8 during state S1.

Figure IB shows embodiments of additional graphs a5, a6, and a7 for illustrating soft pulsing. Each of the graphs a5 to a7 plots RMS values for the time t, which are examples of the first variable. Graph a5 has a constant value, for example, a set of amplitudes A9 during state S0 and a slope of zero during state S0. In addition, graph a5 increases RMS values from a low value in state S0 to a high value in state S1. Graph a5 has a set of amplitudes A10 during state S1. Graph a5 has a negative linear slope during state S1 and reaches the constant value of state S0 at the end of state S1. Graph a5 is referred to herein as a negative sawtooth waveform.

Graph a6 is a sine curve. Graph a6 has a negative sinusoidal slope during state S0 and a positive sinusoidal slope during state S1. Graph a6 has a set of amplitudes A11 during state S0 and a set of amplitudes A12 during state S1.

Graph a7 is a sine curve clamped at the top and bottom of the sinusoid. Graph a7 has a slope of zero during the first portion of state S0 and a negative sinusoidal slope during the second portion of state S0 and has a slope of zero during the remaining third portion of state S0. In addition, graph a7 has a slope of zero during the first portion of state S1 and a positive sinusoidal slope during the second portion of state S1, and has a slope of zero during the remaining third portion of state S1. Graph a7 has a set of amplitudes A13 during state S0 and a set of amplitudes A14 during state S1.

Figure 1C-1 illustrates embodiments of plots a8 and a9 for illustrating soft pulsing. Graphs a8 and a9 each show RMS values, which are examples of the first variable, for time t. Graph a8 has a constant value with a slope of zero during state S0 and transitions to a positive linear slope during state S1 after state S0, in a warped fashion. In addition, the graph a8 continues with a positive linear slope during state S1 and falls back to the constant value of state S0 during the transition from state S1 to state S0. Graph a8 has a set of amplitudes A15 during state S0 and a set of amplitudes A16 during state S1. It should be noted that all the amplitudes of set A15 are the same, e.g., have constant amplitudes.

Graph a9 has a negative linear slope during a portion of the time period of state S0 and a constant value with a slope of zero during the remaining time period of state S0. During state S1, graph a9 increases its RMS value from a low value to a high value and has a sloping amount of exponentially increasing amount. Graph a9 has a set of amplitudes A17 during state S0 and a set of amplitudes A18 during state S1.

FIG. 1C-2 illustrates embodiments of graphs a8 and a9 for illustrating soft pulsing synchronized with the three states S2, S3, and S4. During state S2, graph a8 has the same amplitude. Further, during state S3, graph a8 transitions from the amplitude of state S2 to amplitudes with a positive bend slope. Also, during state S4, graph a8 transitions from a positive warped slope to a positive linear slope. For example, during transition from state S3 to state S4, there is no change in the slope of graph a8. As another example, during a transition from state S3 to state S4, there is a minimum change in the slope of graph a8, e.g., a slope change within a predetermined range, and so on. As another example, during transition from state S3 to state S4, there is continuity in the slope of graph a8. During transition from state S4 to state S2, graph a8 transitions back to the amplitude of state S2.

During state S2, graph a9 has the same amplitude. In addition, during state S3, graph a9 has an amplitude with a positive curved slope. During state S4, graph a9 has a negative linear slope. During transition between states S4 and S2, graph a9 transitions from the amplitude with negative linear slope to the amplitude of state S2.

1D-1 illustrate embodiments of graphs a10, a11, a12, and a13 to illustrate soft pulsing. Plots a10 to a13 plot the RMS values for time t, which are examples of the first variable, respectively. Graph a10 has a constant value with a slope of zero during state S0. In addition, graph a10 has a positive linear slope during the time period of state S1 and a constant value with a slope of zero after time period during state S1. During transition from state S1 to state S0, graph a10 transitions to a constant value of state S0. Graph a10 is a positive clamped sawtooth waveform similar to the positive sawtooth waveform of graph a1 (Fig. 1A) except that a positive sawtooth waveform is clamped at the top. Graph a10 has a set of amplitudes A19 during state S0 and a set of amplitudes A20 during state S1.

Graph a11 has a constant value during state S0 and has a slope of zero. The graph a11 transitions from a constant value to a high value during the transition from the state S0 to the state S1 and maintains a constant value for the time period during the state S1. After a time period, graph a11 has a negative linear slope during state S1 to achieve a constant value of state S0. Graph a11 has a set of amplitudes A21 during state S0 and a set of amplitudes A22 during state S1. Graph a11 is the mirror image of graph a10. Graph a11 has a set of amplitudes A21 during state S0 and a set of amplitudes A22 during state S1.

In some embodiments, the time period in which graph a11 has a negative linear slope during state S1 is part of state S0 instead of state S1.

Graph a12 has a constant value during state S0 and then increases to a high positive slope during state S1. During state S1, graph a12 continues the positive slope during the time period to reach a constant value after a time period. Graph a12 has a constant value of state S1 having a slope of 0 during state S1 and is reduced to a constant value of state S0 during transition from state S1 to state S0. Graph a12 has a set of amplitudes A23 during state S0 and a set of amplitudes A24 during state S1. Note that each of the amplitudes within the set of amplitudes A23 is the same.

The graph a13 has a constant value during the state S0 and then increases to an exponentially increasing slope of the amount of bending to a high value during the state S1. During state S1, after transition from the constant value of state S0, graph a13 has a high value with a slope of 0 for a time period and a negative linear slope during the remaining time period during state S1 to achieve a constant value of state S0 . Graph a13 has a set of amplitudes A25 during state S0 and a set of amplitudes A26 during state S1. Note that each of the amplitudes in the set of amplitudes A25 is the same.

In some embodiments, the time period in which graph a13 has a negative linear slope during state S1 is part of state S0 instead of state S1.

1D-2 show graphs a12 and a13 for illustrating the soft pulsing of the first variable in synchronization with the three states (S2, S3, and S4) of the pulsed signal. During state S2, graph a12 has the same amplitude. In addition, during state S3, graph a12 has a positive curved slope and during state S4, graph a12 has a slope of zero. During transition from state S4 to state S2, graph a12 achieves the amplitude of state S2 from the amplitude with a slope of zero.

In some embodiments, state S4 has a positive oblique slope of graph a12 instead of a constant zero slope in graph a12. For example, during transition from state S3 to state S4, graph a12 continues with a positive curved slope instead of a transition to a constant zero slope.

During state S2, graph a13 has the same amplitude. Moreover, during state S3, graph a13 has a positive exponentially increasing curvature slope. During state S4, graph a13 has a slope of zero for a time period and then transitions to a negative linear slope for the remainder of state S4.

In some embodiments, during state S4, graph a13 has a slope of zero for a time period and then transitions to a negative slope for the remainder of state S4.

Figure IE shows embodiments of plots a14, a15, and a16 for illustrating soft pulsing. Each of the graphs a14 to a16 plots RMS values, which are examples of the first variable, with respect to time t. Graph a14 has a constant value with a slope of 0 for a time period during state S0 and a negative linear slope after a time period during state S0. Graph a14 has a positive linear slope for a time period during state S1 to achieve a constant value and a constant value with a slope of zero after time period during state S1. Graph a14 has a set of amplitudes A27 during state S0 and a set of amplitudes A28 during state S1. Graph a14 is similar to graph a3 in Fig. 1a except graph a14 is clamped at the top.

Graph a15 has a negative linear slope for a time period during state S1 to achieve a constant value and a constant value with a slope of zero for the remaining time period during state S0. Graph a15 has a constant value for a time period during state S1 and transitions to have a positive linear slope after a time period. Graph a15 has a set of amplitudes A29 during state S0 and a set of amplitudes A30 during state S1. Graph a15 is similar to graph a3 in Fig. 1a except that graph a15 is clamped at the lower end.

Graph a16 has a constant value in the slope of 0 for the first time period during state S0 and a negative linear slope for the second time period during state S0 and a constant value with a slope of zero for the remaining time period during state S0. In addition, during the first time period of state S1, graph a16 has a constant value of graph a16 for the remaining time period of state S0. Graph a16 has a positive linear slope during the second time period during state S1 and a constant value with a slope of zero during the remaining time period during state S1. Graph a16 has a set of amplitudes A31 during state S0 and a set of amplitudes A32 during state S1. Graph a16 is similar to graph a3 in Fig. 1a except that graph a16 is clamped at the top and bottom.

In some embodiments, graph a16 has a slope of zero for the remaining time period of state S0 and then has a linear slope of the state S1 amount instead of having a constant value during the first time period of state S1.

Figure 1F illustrates embodiments of graphs a17 and a18 for illustrating soft pulsing. Plots a17 and a18 each plot RMS values for time t, which are examples of a first variable. Graph a17 is similar to graph a16 of Fig. 1e except that the time period of state S0 is longer than the time period of state S1. Graph a17 has a set of amplitudes A33 during state S0 and a set of amplitudes A34 during state S1. In addition, graph a18 is similar to graph a16 in Fig. 1E except that the time period of state S1 is longer than the time period of state S0. Graph a18 has a set of amplitudes A35 during state S0 and a set of amplitudes A36 during state S1.

In some embodiments, any of the graphs described herein are shifted right or left by 1/2 of the state.

In various embodiments, any of the linear slopes described herein are warped slopes, e.g., exponential slopes, sinusoidal slope, and the like.

In some embodiments, any of the curved slopes described herein are linear slopes.

Figure 2a illustrates an example of graphs b1, b2, b3, and b4 for illustrating soft pulsing of a second variable, e.g., variable 2, etc., or a second parameter, e.g., parameter 1, / RTI > Examples of the second variable are the same as those of the first variable except that the second variable is of a type different from the first variable. For example, when the first variable is power, the second variable is frequency. In another example, when the first variable is frequency, the second variable is power. In another example, when the first variable is a voltage, the second variable is a current. Examples of the second parameters are the same as those of the first parameter except that the second parameter is of a type different from the first parameter. For example, when the first parameter is a gap, the second parameter is pressure. As another example, when the first parameter is pressure, the second parameter is the flow rate.

Graph b1 is similar to graph a1 (Fig. 1a) except graph b1 is for the second variable. During state S0, graph b1 has a set of amplitudes B1 and during state S1, graph b1 has a set of amplitudes B2. In addition, graph b2 is similar to graph a2 (Fig. 1A) except that graph b2 is for the second variable. During state S0, graph b2 has a set of amplitudes B3 and during state S1, graph b2 has a set of amplitudes B4. Graph b3 is also similar to graph a3 (Fig. 1a) except graph b3 is for the second variable. During state S0, graph b3 has a set of amplitudes B5 and during state S1, graph b3 has a set of amplitudes B6. Graph b4 is also similar to graph a4 (Fig. 1a) except graph b4 is for the second variable. During state S0, graph b4 has a set of amplitudes B7 and during state S1, graph b4 has a set of amplitudes B8.

Figure 2B illustrates embodiments of graphs b5, b6, and b7 for illustrating the soft pulsing of the second variable. Graph b5 is similar to graph a5 (Fig. 1B) except that graph b5 is for the second variable. During state S0, graph b5 has a set of amplitudes B9 and during state S1, graph b5 has a set of amplitudes B10. In addition, graph b6 is similar to graph a6 (Fig. 1B) except graph b6 is for the second variable. During state S0, graph b6 has a set of amplitudes B11 and during state S1, graph b6 has a set of amplitudes B12. Graph b7 is also similar to graph a7 (Fig. 1b) except graph b7 is for the second variable. During state S0, graph b7 has a set of amplitudes B13 and during state S1, graph b7 has a set of amplitudes B14.

Figure 2c-1 illustrates embodiments of graphs b8 and b9 for illustrating the soft pulsing of the second variable. Graph b8 is similar to graph a8 (Fig. 1C-1) except graph b8 is for the second variable. During state S0, graph b8 has a set of amplitudes B15, and during state S1, graph b8 has a set of amplitudes B16. Each amplitude of set B15 is equal. In addition, graph b9 is similar to graph a9 (Fig. 1C-1) except that graph b9 is for the second variable. During state S0, graph b9 has a set of amplitudes B17 and during state S1, graph b9 has a set of amplitudes B18.

Figure 2c-2 shows embodiments of graphs b8 and b9 for illustrating the soft pulsing of the second variable in synchronization with the three states (S2, S3, and S4). It should be noted that graph b8 is similar to graph c8 of Figure 1c-2 except that graph b8 illustrates the soft pulsing of the second variable. In addition, graph b9 is similar to graph a9 (Fig. 1C-2) except that graph b9 illustrates the soft pulsing of the second variable.

2d-1 illustrate embodiments of graphs b10, b11, b12, and b13 for illustrating the soft pulsing of the second variable. Graph b10 is similar to graph a10 (Fig. 1d-1) except graph b10 is for the second variable. During state S0, graph b10 has a set of amplitudes B19 and during state S1, graph b10 has a set of amplitudes B20. In addition, the graph b11 is similar to graph a11 (Fig. 1D-1) except that graph b11 is for the second variable. During state S0, graph b11 has a set of amplitudes B21 and during state S1, graph b11 has a set of amplitudes B22. Graph b12 is also similar to graph a12 (Fig. 1d) except graph b12 is for the second variable. During state S0, graph b12 has a set of amplitudes B23 and during state S1, graph b12 has a set of amplitudes B24. Graph b13 is also similar to graph a13 (Fig. 1d) except graph b13 is for the second variable. During state S0, graph b13 has a set of amplitudes B25 and during state S1, graph b13 has a set of amplitudes B26.

Figure 2D-2 shows embodiments of graphs b12 and b13 to illustrate soft pulsing of a second variable in synchronization with three states (S2, S3, and S4). Graph b12 is similar to graph a12 in Fig. 1d-2 except that graph b12 plots the second variable with respect to time. In addition, graph b13 is similar to graph a13 in Fig. 1d-2, except graph b13 plots the second variable with respect to time.

Figure 2e illustrates embodiments of graphs b14, b15, and b16 for illustrating the soft pulsing of the second variable. Graph b14 is similar to graph a14 (Fig. 1e) except graph b14 is for the second variable. During state S0, graph b14 has a set of amplitudes B27 and during state S1, graph b14 has a set of amplitudes B28. In addition, graph b15 is similar to graph a15 (Fig. IE) except that graph b15 is for the second variable. During state S0, graph b15 has a set of amplitudes B29 and during state S1, graph b15 has a set of amplitudes B30. Graph b16 is also similar to graph a16 (Fig. 1e) except graph b16 is for the second variable. During state S0, graph b16 has a set of amplitudes B31 and during state S1, graph b16 has a set of amplitudes B32.

Figure 2f illustrates embodiments of graphs b17 and b18 for illustrating the soft pulsing of the second variable. Graph b17 is similar to graph a17 (Fig. 1F) except graph b17 is for the second variable. During state S0, graph b17 has a set of amplitudes B33 and during state S1, graph b17 has a set of amplitudes B34. In addition, graph b18 is similar to graph a18 (Fig. 1F) except graph b18 is for the second variable. During state S0, graph b18 has a set of amplitudes B35 and during state S1, graph b18 has a set of amplitudes B36.

In various embodiments, the two graphs have similar and different or the same statistical measurement values when the graph has the same shape, e.g., shape, and the like. For example, graphs with sinusoidal shapes are similar in shape except that the peak-to-peak amplitude of the first of the graphs is greater than the peak-to-peak amplitude of the second of the graphs.

In some embodiments, the cycle comprising state S1 and state S0 has a time period of several milliseconds, e.g., 2 ms, 3 ms, and so on. In various embodiments, states S1 and S0 have the same duty cycle. State S1 is continuous to state S0. In some embodiments, state S1 has a different duty cycle, e.g., greater than, or less than, the duty cycle of state S0. State S1 is continuous to state S0.

In some embodiments, the positive slope or negative slope may be at least a few percent of the duty cycle during a cycle of statistical measurement signals, such as an RMS waveform, a peak-to-peak amplitude waveform, etc., %, 10%, and so on.

It should be noted that, in each of Figs. 1A-1F and 2A-2F, the graph as used herein is a statistical measurement of the RF signal shown in the figure. For example, graph a1 in FIG. 1A is a signal having an RMS value of an RF signal. A signal having an RMS value is shown in FIG.

Although the graphs of FIGS. 1A-1F and FIGS. 2A-2F plot RMS values, in some embodiments, the graphs plotted any other statistical measurements of sinusoidal RF signals generated by the RF generators It should be noted that.

FIG. 3 is a plot of embodiments of graphs 105 and 107 to illustrate the RMS values of the sinusoidal signals generated by the RF generator, with graphs a1 through a18 and graphs b1 through b18. The graph 105 includes a plot, e.g., a waveform, of the sinusoidal RF signal 102 generated by the RF generator for time t. The sinusoidal RF signal 102 includes a first portion 101 generated during state S0 and a second portion 103 generated during state S1. The plot 106 of the graph 105 is a statistical measurement of the sinusoidal RF signal 102 for time t, e.g., an envelope, a peak-to-peak amplitude,

Similarly, graph 107 includes a plot of the sinusoidal RF signal 108 generated by the RF generator for time t. Graph 107 includes a statistical measurement 110 of sinusoidal RF signal 108 for time t.

Figure 4 shows the RF signal generated by the RF generator to achieve the first variable and the second variable at the same time as shown in either graphs b1 to b18, as shown in any of the graphs a1 to a18. Lt; RTI ID = 0.0 > RF < / RTI > For example, the RF generator may be controlled by a digital signal processor (DSP) of the RF generator to generate an RF signal to achieve the first variable of graph a1 while another RF generator may be controlled by a RF Lt; RTI ID = 0.0 > RF < / RTI > As another example, the RF generator may be controlled by the DSP of the RF generator to generate an RF signal to achieve the first variable of graph a16 while another RF generator may generate an RF signal to achieve the second variable of graph b10 It is controlled by the DSP of another RF generator. As another example, the RF generator may be controlled by the DSP of the RF generator to generate an RF signal to further achieve the first variable of any of the graphs a1 to a18, while another RF generator may be controlled by the DSPs of graphs b1 to b18 And is controlled by the DSP of another RF generator to produce an RF signal to achieve any one second variable. As another example, the DSP of the RF generator may provide a first variable as illustrated in any of graphs a1 to a18 to generate an RF signal having a first variable, and the DSP of another RF generator may provide a second variable Lt; RTI ID = 0.0 > b1-b18 < / RTI > As another example, the DSP of the RF generator may provide a first variable having a function as illustrated in graph a3 to generate an RF signal having a first variable, as illustrated in graph a3, The DSP further provides a second variable having a function as illustrated in graph b5 to generate an RF signal having a second variable, as illustrated in graph b5.

As used herein, a processor includes an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a central processing unit (CPU), or a controller, microprocessor, or combination thereof.

FIG. 5 illustrates embodiments of a number of graphs g1, g2, g3, and g4 to illustrate the similarity between graphs g1 through g4. The graph g1 shows RMS values, which are examples of the first variable, the graph g2 shows RMS values which are examples of the second parameter, the graph g3 shows an example of the first parameter, and the graph g4 shows an example of the second parameter.

Each of the graphs g1 to g4 was plotted on the time axis with time t. For example, states S1 and S0 in graph g1 are represented by functions of times t1, t2, t3, and t4. Similarly, the states S1 and S0 of each of the graphs g2 to g4 are expressed as a function of t1 to t4.

In various embodiments, each of the first variable, the second variable, the first parameter, and the second parameter has the same type of slope during the state. For example, as shown in graphs g1 to g4, each of the first variable, the second variable, the first parameter, and the second parameter has a constant value in state S0 or a negative slope during state S0, Has a positive slope during S1 or has a constant value during state S1. Examples of types of slope include a slope of zero, a positive slope and a negative slope.

In some embodiments, any one of the first variable, the second variable, the first parameter, and the second parameter is selected from the group consisting of a slope of any one of the first variable, the second variable, the first parameter, Have different types of slopes. For example, the first variable has a positive slope during state S 1 and the second variable has a negative slope during state S 1. Also, in this example, the first variable has a negative slope during state S0 and the second variable has a positive slope during state S0. As another example, the first parameter has a constant slope during state S 1 and the second parameter has a negative slope during state S 1. Also, in this example, the first parameter has a positive slope during state S0 and the second parameter has a constant slope during state S0.

In some embodiments, any number of variables, e.g., 1, 2, 3, 4, 6, etc., and any number of parameters are used to control the plasma chamber.

In various embodiments, graph g1 is a statistical measurement of the RF signal generated by the x MHz RF generator and graph g2 is a statistical measurement of the RF signal generated by the y or z MHz RF generator.

It should be noted that although the waveform shape is illustrated in graphs g1 to g4, in some embodiments, waveforms of the shapes shown in other shapes, e.g., graphs a1 to a3 and a5 to a18, etc., are applicable .

In each of Figs. 1A-1F and Figs. 2A-2F, 3 and 5, a digital pulsed signal, e.g. a transistor-transistor logic (TTL) signal, a digital clock signal, Signal, a signal having a high level and a low level, a signal having three levels, etc. are shown by dotted lines.

6A is a diagram of an embodiment of a plasma system 300 for performing soft pulsing using a digitally pulsed signal from a host system 312. The plasma system 300 is shown in FIG. Examples of host system 312 include computers, e.g., desktops, laptops, tablets, and the like. By way of example, host system 312 includes a processor and a memory device. Examples of memory devices include read-only memory (ROM), random access memory (RAM), or a combination thereof. Other examples of memory devices include flash memory, redundant array of storage disks (RAID), hard disks, and the like.

The host system 312 is coupled to an x MHz RF generator, a y MHz RF generator, and a z MHz RF generator. Examples of x MHz include 2 MHz, 27 MHz, and 60 MHz. Examples of y MHz include 2 MHz, 27 MHz, and 60 MHz. Examples of z MHz include 2 MHz, 27 MHz, and 60 MHz.

x MHz is different from y MHz and z MHz. For example, when x MHz is 2 MHz, y MHz is 27 MHz and z MHz is 60 MHz.

Each of the RF generators includes a DSP, a set of power controllers, a set of automatic frequency tuners (AFT: automatic frequency tuners), and an RF power source. For example, the x MHz RF generator includes a digital signal processor DSPx, a power controller (PCS1x), a power controller (PCS0x), an automatic frequency tuner (AFTS1x), an automatic frequency tuner (AFTS0x), and an RF power source PSx. As another example, the y MHz RF generator includes a digital signal processor DSPy, a power controller PCS1y, a power controller PCS0y, an automatic frequency tuner AFTS1y, an automatic frequency tuner AFTS0y, and an RF power source PSy. As another example, the z ㎒ RF generator includes a digital signal processor DSPz, a power controller PCS1z, a power controller PCS0z, an automatic frequency tuner AFTS1z, an automatic frequency tuner AFTS0z, and an RF power source PSz.

The x, y, and z MHz RF generators are connected to an impedance matching circuit (IMC) 302 via RF cables. For example, the x MHz RF generator is coupled to the IMC 302 via an RF cable 304, the y MHz RF generator is coupled to the IMC 302 via an RF cable 320, and the z MHz RF generator And is coupled to the IMC 302 via an RF cable 322.

In various embodiments, the RF cable includes an inner conductor surrounded by an insulating material, surrounded by an outer conductor, surrounded by a jacket. In some embodiments, the outer conductor comprises a braided wire and the jacket comprises an insulative material.

The IMC 302 is coupled to the plasma chamber 308 via RF transmission line 310. In various embodiments, RF transmission line 310 includes a cylinder, for example, a tunnel connected to IMC 302, or the like. Insulators and RF rods are placed in the hollow space of the cylinder. The RF transmission line 310 further includes an RF spoon, for example, an RF strap coupled to the RF rod of the cylinder at one end, and the like. The RF spoon is coupled to the RF rod of the vertically positioned cylinder at the other end and the RF rod is coupled to the chuck 132 of the plasma chamber 308.

The plasma chamber 308 includes a chuck 132 and an upper electrode 134. Examples of the chuck 132 include an electrostatic chuck (ESC) and a magnetic chuck. The plasma chamber 308 includes one or more other portions (not shown), for example, an upper dielectric ring surrounding the upper electrode 134, an upper electrode extension surrounding the upper dielectric ring, A lower electrode extension surrounding the lower dielectric ring, an upper PEZ (plasma exclusion zone) ring, a lower PEZ ring, and the like. The upper electrode 134 is located on the opposite side of the chuck 132 or opposite. A workpiece 324, e.g., a semiconductor substrate, a semiconductor substrate with integrated circuitry, a wafer, etc., is supported on top surface 327 of chuck 132. The lower surface of the upper electrode 134 is opposite the upper surface 327 of the chuck 132.

Various processes, such as chemical vapor deposition, cleaning, deposition, sputtering, etching, ion implantation, resist stripping, etc., are performed on the workpiece 324 during production. Integrated circuits, such as ASICs, PLDs, etc., are deployed on the workpiece 324 and the integrated circuits may be implemented in a variety of electronic devices, such as mobile phones, tablets, smart phones, computers, , And so on. Each of the lower electrode and the upper electrode 134 is made of a metal, for example, aluminum, an aluminum alloy, copper, or the like. The upper electrode 132 is coupled to a reference voltage, e. G., Ground voltage, constant voltage, and the like.

The processor of the host system 312 generates a digital pulsed signal 326, which is a digital signal having two states. For example, a digitally pulsed signal has a slope of zero or an infinite slope. In some embodiments, instead of the host system 326, a clock oscillator, e.g., a crystal oscillator, etc., is used to generate an analog clock signal, which is converted to a digitally pulsed signal 326 by an analog- do.

The digitally pulsed signal 326 has two states, state S1 and state S0. In various embodiments, the digitally pulsed signal 326 is a TTL signal. Examples of states S1 and S0 include an on state and an off state, a state having a digital value of 1 and a state having a digital value of 0, and a high state and a low state, and the like. For example, state S1 is high and state SO is low. As another example, state S 1 has a digital value of 1 and state S 0 has a digital value of 0. As another example, state S1 is on and state S0 is off.

The DSP x receives the digitally pulsed signal 326 and identifies the states of the digitally pulsed signal 326. For example, the DSPx may be configured such that the digital pulsed signal 326 has a first magnitude, e.g., a digital value of 1, a high state, etc., during a first time period of the duty cycle, and during a second time period of the duty cycle For example, a digital value of zero, a low state, and so on. DSPx determines that digital pulsed signal 326 has state S1 for the first time period and state S0 for the second time period. Examples of state S0 include a low state, a state having a value of 0, and an off state. Examples of state S1 include a high state, a state having a value of 1, and an on state. As another example, DSPx may determine that the magnitude of the digitally pulsed signal 326 is greater than a pre-stored value during the first time period and that the magnitude of the digitally pulsed signal 326 during state S0 is less than a pre- And the magnitude of the digitally pulsed signal 326 is compared. In an embodiment where a clock oscillator is used, the DSPx receives an analog clock signal from the clock oscillator, converts the analog signal to digital form, and then identifies the two states S0 and S1.

When the state of the digitally pulsed signal 326 is identified as S1, the DSPx provides the power value Px1 to the power controller PCS1x and the frequency value Fx1 to the AFTS1x. Examples of the power value Px1 include the RMS value of the state S1 of any of the signals illustrated in graphs a1 to a18. For purposes of illustration, the power value Px1 is the amplitude (A2, A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28, A30, A32, A34, 1a, 1b, 1c-1, 1d-1, and 1e-1f). Examples of the frequency value Fx1 include the RMS value of the state S1 of any of the signals illustrated in the graphs b1 to b18. For the sake of example, the frequency value Fx1 is the amplitude (B2, B4, B6, B8, B10, B12, B14, B16, B18, B20, B22, B24, B26, B28, B30, B32, B34, 2a, 2b, 2c-1, 2d-1, and 2e-2f).

Further, when the state is identified as S0, the DSPx provides the power value Px0 to the power controller PCS0x and the frequency value Fx0 to the AFTS0x. Examples of the power value Px0 include the RMS value of the state S0 of any of the signals illustrated in graphs a1 through a18. For example, the power value Px0 is the amplitude (A1, A3, A5, A7, A9, A11, A13, A15, A17, A19, A21, A23, A25, A27, A29, A31, A33, 1a, 1b, 1c-1, 1d-1, and 1e-1f). Examples of the frequency value Fx0 include the RMS value of the state S0 of any of the signals illustrated in the graphs b1 to b18. For example, the frequency value Fx0 is the amplitude (B1, B3, B5, B7, B9, B11, B13, B15, B17, B19, B21, B23, B25, B27, B29, B31, B33, 2a, 2b, 2c-1, 2d-1, and 2e-2f).

It should be noted that in some embodiments, the AFTs of the RF generator and the power controllers of the RF generator are one or more logic blocks. For example, the power controllers PCS1x and PCS0x and the automatic frequency tuners AFTS1x and AFTS0x are tuning loops, which are logical blocks, e.g., part of a computer program executed by DSPx, and so on. In some embodiments, the computer program is implemented in a non-volatile computer-readable medium, e.g., a memory device.

In one embodiment, a hardware device, e.g., a hardware controller, an ASIC, a PLD, etc., is used in place of the logical block of the RF generator. For example, a hardware controller is used instead of the power controller PCS1x, another hardware controller is used instead of the power controller (PCS0x), another hardware controller is used instead of AFTS1x, and another hardware controller is used instead of AFTS0x.

Upon receipt of the power value Px1, during state S1, the power controller PCS1x is used to generate a portion of the sinusoidal signal during state S1 and determines the values of power with the RMS value of Px1. Similarly, upon receipt of the power value Px0, during state S0, the power controller PCS0x is used to generate a portion of the sinusoidal signal during state S0 and determines the values of power with the RMS value of Px0.

Further, upon receiving the frequency value Fx1, during state S1, the automatic frequency tuner AFTS1x is used to generate a portion of the sinusoidal signal during state S1 and determines the frequency value with the RMS value of Fx1. Similarly, upon receiving the frequency value Fx0, during state S0, the automatic frequency tuner AFTS0x is used to generate a portion of the sinusoidal signal during state S0 and determines the frequency value with the RMS value of Fx0.

During state S1, the power controller PCS1x provides the power values generated from the RMS power value Px1 to the RF power source PSx. In addition, during state S1, the AFTS1x provides the RF power source PSx with the frequency values generated from the RMS frequency value Fx1. During state S1, the RF power source PSx receives an RF signal 102 (FIG. 3) having power values generated from a portion of the RF signal, for example, the RMS power value Px1, and having frequency values generated from the RMS frequency value Fx1, RF signal 108 (FIG. 3), and so on.

Similarly, during state S0, the power controller (PCS0x) provides the power values generated from the RMS power value Px0 to the RF power source PSx. In addition, during state SO, AFTS0x provides frequency values generated from the RMS frequency value Fx0 to the RF power supply PSx. During state S0, the RF power source PSx receives an RF signal 102 (FIG. 3) having power values generated from the remainder of the RF signal, for example, the RMS power value Px0, and having frequency values generated from the RMS frequency value Fx0, , RF signal 108 (Fig. 3), and the like. The RF signal generated by the RF generator based on the power values and / or frequency values is a sinusoidal signal, e.g. not a constant, not an exponent, etc. The RF signal generated by the x MHz RF generator is supplied to the IMC 302 via the RF cable 304.

The DSPx provides a digitally pulsed signal 326 to the DSPy of the y MHz RF generator and the DSPz of the z MHz RF generator. When the x MHz RF generator provides the digital pulsed signal 326 to the y and z MHz RF generators, the x MHz RF generator functions as a master RF generator and DSPx functions as a master controller. On receipt of the digitally pulsed signal 326, the y and z MHz RF generators generate sinusoidal RF signals in a manner similar to the generation of an RF signal based on a digitally pulsed signal 326 by an x ㎒ RF generator. The RF signal generated by the y MHz RF generator is supplied to the IMC 302 via the RF cable 320 and the RF signal generated by the z MHz RF generator is supplied to the IMC 302 via the RF cable 322 . Examples of RF signals generated by the y MHz or z MHz RF generator are amplitudes A1 and A2 (FIG. 1A), or amplitudes A3 and A4 (FIG. 1A), or amplitudes A5 and A6 (FIG. 1A) Or amplitudes A13 and A14 (FIG. 1B), or amplitudes A15 and A16 (FIG. 1B), or amplitudes A11 and A12 (Fig. 1C-1), or amplitudes A17 and A18 (Fig. 1C-1), or amplitudes A19 and A20 Or amplitudes A31 and A32 (FIG. 1E), or amplitudes A31 and A32 (FIG. 1D) (FIG. 1e), or amplitudes A33 and A34 (FIG. 1f), or amplitudes A35 and A36 (FIG.

The IMC 302 receives the RF signals from the x, y, and z MHz RF generators and sends the impedance of the source coupled to the IMC 302 to the IMC 302 to generate a modified RF signal 306 Matches the impedance of the coupled load. For example, the IMC 302 may convert the impedance of the RF transmission line 310 and the plasma chamber 308 to an x ㎒ RF generator, a y ㎒ RF generator, a z ㎒ RF generator, Matching the impedance of the RF cable 304, the RF cable 320, and the RF cable 322. As another example, the IMC 302 may be coupled to the IMC 302 as an impedance and load of any components of the plasma system 300 coupled to the IMC 302 as a source to generate a modified RF signal 306 Matching the impedance of any of the components of the ringed plasma system (300). Examples of components coupled to the IMC 302 as a load include an RF transmission line 310, a plasma chamber 308, and a plasma chamber 308 on the IMC 302 on the side of the IMC 302 where the plasma chamber 308 is located. And any other components, such as coupled, e.g., filters, and the like. Examples of components coupled to IMC 302 as a source include x, y, and z RF generators, RF cables 304, 320, and 322, and x, y, Such as, for example, a filter, etc. coupled to the side of the < RTI ID = 0.0 > IMC 302. < / RTI >

The modified signal 306 is transmitted by the IMC 302 to the chuck 132 via the RF transmission line 310. When one or more process gases are supplied between the upper electrode 134 and the chuck 132 and the modified RF signal 306 is supplied to the chuck 132, one or more process gases are introduced into the plasma chamber 308, Lt; / RTI >

In various embodiments, the upper electrode 132 includes one or more inlets, e.g., a hole coupled to a central gas supply (not shown), and the like. The central gas supply contains one or more process gases from a gas source, for example, a gas reservoir, or the like. An example of the process gas includes an oxygen-containing gas such as O ₂ . Other examples of process gases include, for example, fluorine-containing gases such as tetrafluoromethane (CF ₄ ), sulfur hexafluoride (SF ₆ ), hexafluoroethane (C ₂ F ₆ ), and the like.

6B is a diagram of an embodiment of a plasma system 350 for illustrating the application of soft pulsing to a plurality of variables. Plasma system 350 includes x, y, and z MHz RF generators, IMC 302, and plasma chamber 308. The plasma system 350 further includes a phase delay circuit 138, a gap control system 362, a pressure control system 364, and a flow control system 366.

In some embodiments, instead of the phase delay circuit 138, a processor, e.g., a processor of the host system 312, generates a phase delay of the digitally pulsed signal 326.

The gap control system 362 includes a gap processor 130, a gap driver GDS1 for state S1, and a gap driver GDS0 for state S0. In addition, the pressure control system 364 includes a pressure processor 140, a pressure controller PCS1 for state S1, and a pressure controller PCS0 for state S0. The flow control system 366 also includes a flow processor 146, a flow driver FDS1 for state S1, and a flow driver FDS0 for state S0.

In some embodiments, the driver or controller includes one or more transistors to generate a current signal.

The plasma system 350 also includes a motor 136 coupled to the gap control system 362 and the upper electrode 134, limited ring portions 142A and 142B of the plasma chamber 308 and a pressure control system 364 A motor 144 and a motor 150 connected to the valve 148 and the flow control system 366. [ It should be noted that the confinement ring portion 142A and the confinement ring portion 142B form one or more confinement rings 142.

The motor 136, the top electrode 134, and / or the chuck 132 are sometimes referred to herein as gap control mechanical components. In addition, the motor 144 and / or the limited rings 142 are sometimes referred to herein as pressure-controlled mechanical components. In addition, motor 150, gas source GS1, and / or valve 148 are sometimes referred to herein as flow control mechanical components.

In some embodiments, the motor 136 is connected to the chuck 132 instead of the upper electrode 134 to move the chuck 132 in place of the upper electrode 134. In various embodiments, the motor is connected to the chuck 132, the other motor is connected to the upper electrode 132, and the two motors are connected to the gap control system 362.

In various embodiments, the confinement rings 142 comprise a conductive material, such as silicon, polysilicon, silicon carbide, boron carbide, ceramic, aluminum, and the like. Typically, the confinement rings 142 surround the volume 382 of the plasma chamber 308 to form the plasma. In various embodiments, in addition to the confinement rings 142, the perimeter of the volume 382 may include an upper electrode 134, a chuck 132, one or more insulator rings, e.g., between the electrode and the electrode extension, Dielectric rings between the extension and the lower electrode extension, and the like.

Examples of motors include electric machines that convert electrical energy into mechanical energy. Other examples of motors include alternating current (AC) motors. Other examples of motors include machines that include moving parts such as rotors and stationary parts such as stator. There is an air gap between the stator and the rotor.

Examples of valves include devices that regulate, direct, or control the flow of gas or liquid by blocking the passage, e.g., opening, closing, or partially blocking the passage of the casing. Other examples of valves include hydraulic valves, manual valves, solenoid valves, motor valves and pneumatic valves.

The digital pulsed signal 326 is generated by the processor of the host system 312 and provided to the phase delay circuit 138. The phase delay circuit 138 receives the digital pulsed signal 326 and delays the digitally pulsed signal 326 by a predefined phase to produce a modified pulsed signal 368. The phase delay may be applied to the mechanical components of the plasma system 350 such as the upper electrode 134, the chuck 132, the valve 148, the motor 136, the motor 144, the motor 150, (S) 142, etc. are provided to the digitally pulsed signal 326 to allow time to respond to the digitally pulsed signal 326. The phase delay circuit 138 is coupled to the host system 312 and the DSPs of the x, y, and z MHz RF generators. The phase delay circuit 138 is configured to provide more time to the plasma system (e.g., the processor) to respond to the digital pulsed signal 326 than the electrical components, e.g., DSPs, RF power supplies, power controllers, AFTs, 350 delayed the phase of the digitally pulsed signal 326 to produce a modified pulsed signal 368 that is further allowed to the mechanical components of the digital pulsed signal. The modified pulsed signal 368 is provided to the DSPs of the x, y, and z MHz RF generators.

In some embodiments, the electrical component responds to the pulsed signal when the electrical component generates an output signal based on the pulsed signal input to the electrical component. In various embodiments, the mechanical component responds to the pulsed signal when the mechanical component performs mechanical motion, e.g., rotation, movement, slide, shift, closure, opening, etc., in response to the pulsed signal.

When the modified pulsed signal 368 is received by the DSPx, the x MHz RF generator generates an RF signal that is synchronized with the modified pulsed signal 368. For example, when the state of the modified pulsed signal 368 transitions from state S0 to state S1, the envelope of the portion of the RF signal changes from a negative slope to a positive slope or zero slope. As another example, a statistical measurement of a portion of the RF signal changes from a positive slope to a negative slope or zero slope when the state of the modified pulsed signal 368 transitions from state S1 to state SO. Similarly, when the modified pulsed signal 368 is received by the DSPy, the y MHz RF generator generates an RF signal that is synchronized with the modified pulsed signal 368 and the modified pulsed signal 368 is coupled to DSPz The z MHz RF generator generates an RF signal that is synchronized with the modified pulsed signal 368. [

It should be noted that in the plasma system 350, the x MHz RF generator is not a master generator. The x MHz RF generator of the plasma system 350 does not generate the digital pulsed signal 326 or provide it to the y MHz and z MHz RF generators. For example, DSPx does not provide digital pulsed signal 326 to DSPy or DSPz.

Mechanical components can control the flow of process gas into the plasma chamber 308 and control the gap between the top electrode 134 and the chuck 132 and / or control the pressure within the plasma chamber 308. In various embodiments, A phase delay is added by the phase delay circuit 138 to shift the digitally pulsed signal 326 to the right on the time t axis to produce a pulsed signal 368 that has been modified to allow more time.

In some embodiments, the digital pulsed signal 326 includes an x MHz RF generator, a y MHz RF generator, electrical components of a z MHz RF generator, RF cables 304 and 320 (Lag) relative to the modified pulsed signal 368 to allow more time for the mechanical components than the time allowed for the RF transceiver 310, and 322, the IMC 302, and the RF transceiver 310. Examples of electrical components include a RF generator's DSP, RF generator's RF power source, transistors, resistors, capacitors, inductors, cables, wires, straps, spoons, rods, .

The gap processor 130 receives the digitally pulsed signal 326 to condition states S1 and S0 from the digitally pulsed signal 326. [ For example, gap processor 130 may be configured to determine states (states) S1 and S0 from digital pulsed signal 326, similar to the manner described above, where DSPs identify states S1 and S0 from digitally pulsed signal 326 (S1 and S0). As another example, the gap processor 130 may determine that the digital pulsed signal 326 has a first magnitude, e.g., a digital value of 1, a high state, etc., during a first time period, For example, a digital value of zero, a low state, and so on.

The gap processor 130 determines the state S1 by comparing the state S1 with a memory device (not shown) coupled to the gap processor 130 to apply a gap between the upper electrode 134 and the chuck 132, A signal of the first variable from one of the values of the parameter signal, for example, the graphs a1 to a18 (Figs. 1A, 1B, 1C-1, 1D-1, 1E, A signal of the second variable from one of the graphs b1 to b18 (Figs. 2A, 2B, 2C-1, 2D-1, 2E and 2F). The gap processor 130 determines whether the memory device coupled to the gap processor 130 (not shown) for state S0 to apply a gap between the upper electrode 134 and the chuck 132, (For example, from one of the graphs a1 to a18 (Figs. 1A, 1B, 1C-1, 1D-1, 1E, 1F) Signal, a signal of a second variable from one of the graphs b1 to b18 (Figs. 2A, 2B, 2C-1, 2D-1, 2E and 2F). The gap processor 130 supplies the values of the parameter signals to be generated during the state S1 to the gap driver GDS1 and the values of the parameter signals to be generated during the state S0 to the gap driver GDS0.

The gap driver GDS1 generates a portion of the parameter signal having values received from the gap processor 130 during state S1 and provides it to the motor 136. [ In addition, the gap driver GDS0 generates the remaining portion of the parameter signal having values received from the gap processor 130 during state S0 and provides it to the motor 136. The motor 136 operates in accordance with the frequency and power of a portion of the parameter signal received from the gap driver GDS1 during state S1, for example, when the rotor rotates and the parameter signal received from the gap driver GDS0 And operates in accordance with the remaining frequency and power. The gap, e.g., distance, etc., between the upper electrode 134 and the chuck 132, when the motor 136 operates during state S1 based on the frequency and power of some of the parameter signals, It changes. In addition, when the motor 136 operates based on the frequency and power of the remaining portion of the parameter signal during state S0, the distance between the top electrode 134 and the chuck 132 varies with frequency and power.

Pressure processor 140 receives digital pulsed signal 326 to identify states S1 and S0 from digital pulsed signal 326 in a manner similar to that described above for gap processor 130 do. The pressure processor 140 receives from the memory device coupled to the pressure processor 140 a portion of the parameter signal to apply to the limited rings 142 for state S1, The signals of the first variable of one of the graphs a1 to a18 (Figs. 1A, 1B, 1C-1, 1D-1, 1E and 1F), the graphs b1 to b18 The signal of the second variable of one of Figs. 2A, 2B, 2C-1, 2D-1, 2E, 2F). On the other hand, when it is determined that the state is S0, the pressure processor 140 receives from the memory device coupled to the pressure processor 140 the values of some of the parameter signals to apply to the limited rings 142 for state S0, , The signals of the first variable of one of the graphs a1 to a18 (Figs. 1A, 1B, 1C-1, 1D-1, 1E and 1F), the graphs b1 to b18 2c-1, 2d-1, 2e, 2f) of the second variable. During state S1, pressure processor 140 provides values of the parameter signal for state S1 to pressure controller PCS1. In addition, during state S0, pressure processor 140 provides the values of the parameter signals for state S0 to pressure controller PCS0.

During state S1, pressure controller PCS1 generates a current signal having values of the parameter signal and provides a current signal to motor 144. [ Further, during state S0, pressure controller PCS0 generates a current signal having values of the parameter signal and provides a current signal to motor 144. [ The motor 144 operates with the frequency and power of the values of some of the parameter signals received during state S1. The operation of the motor 144 changes the vertical position of the limiting rings 142 relative to the volume 382 of the plasma chamber 308 according to the frequency and power of the parameter signal to change the pressure in the volume 382 during state & . Similarly, the motor 144 operates with the frequency and power of the values of some of the parameter signals received during state S0. The operation of the motor 144 changes the vertical position of the limiting rings 142 relative to the volume 382 of the plasma chamber 308 according to the frequency and power of the parameter signal to change the pressure in the volume 382 during state S0 .

In various embodiments in which the motor 144 is connected to the limiting rings 142 from the lower end side of the limiting rings 142 the vertical position of the limiting rings 142 may be located above the limiting rings 142 within the volume 382, It is changed to move down. The confinement rings 382 move up to cover a larger volume 382 and move down to cover a smaller volume 382. [

In some embodiments, the motor 144 is connected to the limiting rings 142 from the top side of the limiting rings 142. The confinement rings 382 move down to cover a larger volume 382 and move up to cover a smaller volume 382. [

In some embodiments, the motor 144 is connected to the confinement rings 142 via a rod and the confinement rings 142 are spaced and connected to the grooves of the rod. As the rotors of the motor 144 rotate, the rods are protruded or recessed from the motor to change the vertical position of the confinement rings 142. The load is connected to the motor.

In addition, the flow processor 146 receives the digitized pulsed signal 326 and provides the digital pulsed signal 326 in a similar manner as the DSP identifies the states (S1 and S0) of the digitally pulsed signal 326 Identifies states S1 and S0. The flow processor 146 determines from the memory device coupled to the flow processor 146 the values of some of the parameter signals to apply to the valve 148 for state S1, The signals and graphs b1 to b18 of the first variable of one of a1 to a18 (Figs. 1A, 1B, 1C-1, 1D-1, 1E, 1, 2d-1, 2e, 2f), and so on. On the other hand, when it is determined that the state is S0, the flow processor 146 receives from the memory device coupled to the flow processor 146 the values of some of the parameter signals to apply to the valve 148 for state S0, Graphs b1 to b18 of the first variable of one of the graphs a1 to a18 (Figs. 1A, 1B, 1C-1, 1D-1, 1E and 1F) 2c-1, Fig. 2d-1, Fig. 2e, and Fig. 2f). During state S1, flow processor 146 provides values of the parameter signal for state S1 to flow driver FDS1. In addition, during state S0, flow processor 146 provides values of the parameter signal for state S0 to flow driver FDS0.

During state S1, flow driver FDS1 generates a current signal to drive motor 150 according to the frequency values and power values of some of the parameter signals for state S1. In addition, during state S0, flow driver FDS1 generates a current signal to drive motor 150 according to the frequency values and power values of the remainder of the parameter signal for state S0. The motor 150 operates to vary the position of the valve 148 to open or close a case, e.g., an enclosure, tube, pipe, etc., in which the valve 148 is located. The position of the valve 148 varies with the frequency and power of the parameter signal generated during state S1 and with the frequency and power of the parameter signal generated during state S0. The change in position of the valve 148 during state S1 or state S0 changes, e.g., increases, or decreases, the flow rate of one or more process gases to the volume 382. A process gas or a mixture of process gases is stored in the gas source GS and supplied to the plasma chamber 308 through the passage of the case. The gas source GS is coupled to the plasma chamber 308 through the case. Plasma is generated in the plasma chamber 308 when one or more process gases are supplied to the volume 382 and the modified RF signal 306 is received by the chuck 132 through the RF transmission line 310. Plasma is used to perform one or more of the processing operations described above.

In some embodiments, the motor 150 is connected to the valve 148 via a rod to change the position of the valve by rotation of the rotor of the motor 150.

In various embodiments, instead of motor 150, other mechanical components, such as current drivers, etc., are used to control valve 148. For example, valve 148 is a solenoid valve and flow drivers FDS1 and FDS0 are current drivers for states S1 and S0. In these embodiments, when a portion of the digitally pulsed signal 326 is received by the flow processor 146 during state S1, the flow processor 146 receives the values of the parameter signal from the memory device of the flow control system 366 , For example, the values of any of the signals of the first variable illustrated in the graphs a1 to a18 (Figures 1a, 1b, 1c-1, 1d-1, 1e, the values of the signal of the second variable from one of b18 (Figs. 2A, 2B, 2C-1, and 2E, 2F), and the like. Upon identification of the values of the parameter signal during state S1, the flow processor 146 generates a command signal to indicate to the flow driver FDS1 to generate a portion of the parameter signal during state S1. Similarly, when part of the digitally pulsed signal 326 during state S0 is received by the flow processor 146, the flow processor 146 receives the values of the parameter signal from the memory device of the flow control system 366, For example, any of the signals of the first variable illustrated in the graphs a1 to a18 (Figs. 1A, 1B, 1C-1, 1D-1, 1E and 1F), the graphs b1 to b18 , Fig. 2B, Fig. 2C-1, and Figs. 2E, 2F), and the like. Upon identification of the values of the parameter signal during state S0, flow processor 146 generates a command signal to indicate to flow driver FDS0 to generate a portion of the parameter signal during state S0. The flow driver FDS1 sends part of the parameter signal having the current values generated during state S1 to the valve 148 and the flow driver FDS0 sends part of the parameter signal having the current values generated during state S0 to the valve 148 ). Upon receipt of current values during state S1, the valve 148 is opened or closed in accordance with the current values to control the flow of one or more process gases from the gas source GS to the volume 382 of the plasma chamber 308 . Similarly, upon receipt of the current values during state S0, the valve 148 is opened in response to current values to control the flow of one or more process gases from the gas source GS to the volume 382 of the plasma chamber 308 Or closed.

In some embodiments, any number of gas sources are used in the plasma system 350. Each of the gas sources stores different process gases. For example, one source of gas stores a fluorine-containing gas, and another source of gas stores an oxygen-containing gas. Each of the gas sources is connected to the plasma chamber 308 through a case to supply a gas, e.g., process gas, inert gas, etc., to the plasma chamber 308. The case includes a valve connected to the motor and controlled by the motor, which is also connected to the flow drivers FDS1 and FDS0 and controlled by the flow drivers FDS1 and FDS0.

7 is a diagram of an embodiment of a plasma system 400 for illustrating the use of a master RF generator to generate a digitized pulsed signal 326 and a modified pulsed signal 368 Plasma system 400 may include a pulsed signal 326 and a modified pulsed signal 326 that are received by the y MHz and z ㎒ RF generators in the plasma system 400 in place of the host system 312. [ (FIG. 6B), except that it produces a filtered signal 368. The plasma system 350 (FIG. For example, the clock source of the DSPx or x MHz RF generator produces a digitally pulsed signal 326, which is shifted to the phase delay circuit 138. The phase delay circuit 138 generates a modified pulsed signal 368 from the digitally pulsed signal 326. As another example, the clock oscillator of the x MHz RF generator generates an analog signal that is converted to a digitally pulsed signal 326 by the analog-to-digital converter of the x MHz RF generator, which generates a modified pulsed signal 368 Lt; / RTI > to the phase-delay circuit 138 for < / RTI >

The modified pulsed signal 368 is provided by the x ㎒ RF generator to the y ㎒ RF generator and the z ㎒ RF generator and the digital pulsed signal 326 is provided to the gap control system 362, A pressure control system 364, and a flow control system 366. For example, the phase delay circuit 138 provides a modified pulsed signal 368 to the DSPy and DSPz, and the DSPx outputs the digital pulsed signal 326 to the gap processor 130, the WAP processor 140, and And provides it to flow processor 146. The remaining operations of the plasma system 400 are similar to those described above for the plasma system 350.

In some embodiments, the digitally pulsed signal 326 is received by the x MHz RF generator from the host system 312 coupled to the x MHz RF generator. The x MHz RF generator generates a modified pulsed signal 368 from the digitally pulsed signal 326 and provides the modified pulsed signal 368 to DSPy and DSPz.

In various embodiments, the digital pulsed signal 326 is received by the phase delay circuit 138 from the host system 312 to produce a modified pulsed signal 368. The modified pulsed signal 368 is provided by the phase delay circuit 138 to the x MHz RF generator. The x MHz RF generator provides the modified pulsed signal 368 to DSPy and DSPz.

8 is an illustration of an embodiment of a plasma system 410 for illustrating the use of a feedback system to determine the time of presentation of the next state of the modified pulsed signal 368. [ Plasma system 410 is similar to plasma system 350 (FIG. 6B), except that plasma system 410 includes a feedback system.

The feedback system includes a gap sensor 412, a flow sensor 414, and a pressure sensor 416. Examples of the gap sensor 412 include a laser detector, an optical sensor, an inductive detector, a capacitive detector, a linear variable differential transformer (LVDT) sensor, and the like. In some embodiments, the gap sensor 412 is located outside of the plasma chamber 308 and is positioned within the chamber 382 to determine the gap, e.g., the vertical distance between the upper electrode 134 and the chuck 132, Lt; RTI ID = 0.0 > optically. &Lt; / RTI > Examples of the flow sensor 414 include a flow rate sensor, an optical flow meter, a coriolis flow meter, a mass flow rate sensor, a thermal mass flow rate sensor, and a flow rate sensor, which measure the rate of flow of process gas in standard cubic centimeter per minute (sccm) A volume sensor, a pressure-based meter, and the like. The flow sensor 414 is coupled to an internal volume of the case through an orifice in the case, e.g., a gas line in which the valve 148 is located, The pressure sensor 416 measures the pressure of one or more gases and / or plasma within the plasma chamber 308. Examples of the pressure sensor 416 include an absolute pressure sensor, a vacuum pressure sensor, a differential pressure sensor, a resonance pressure sensor, a heat pressure sensor, an optical pressure sensor, and the like. In some embodiments, the pressure sensor 416 is located outside the volume 382 to measure the pressure of the one or more gases and / or the plasma within the plasma chamber 308.

In embodiments where multiple gas sources are used, a flow sensor is coupled to the case of the gas source to measure the flow rate of the gas flowing from the gas source to the plasma chamber 308. The flow sensor is coupled to flow processor 146 to provide a measured flow rate to flow processor 146.

Plasma system 410 operates in a manner similar to plasma system 350 (FIG. 6B) except that plasma system 410 uses a feedback system. For example, after the gap between the upper electrode 134 and the chuck 132 is changed, the gap sensor 412 measures the gap. The measured gap size is provided to the gap processor 130 by the gap sensor 412. Gap processor 130 determines whether the size of the gap matches the size of the predetermined gap for the state. The size of the predetermined gap for the state is stored in the memory device of the gap control system 362 (Fig. 7). In the memory device, a predetermined gap for the state is associated with the amount of impedance of the plasma in the plasma chamber 308 for the state. For example, the magnitude of the predetermined gap for state S1 is associated with the amount of impedance Z1, and the magnitude of the predetermined gap for state S0 is associated with the amount of impedance Z2. The impedance of the plasma within the plasma chamber 308 is controlled by one or more of the one or more RF signals provided to the plasma chamber 308, the pressure within the plasma chamber 308, 132 and the flow rate of one or more gases flowing into the plasma chamber 308. [

The impedance of the plasma within the plasma chamber 308 is achieved for the state to further achieve an etch rate or deposition rate for the state. For example, the size of the predetermined gap for state S0 helps achieve the impedance to achieve a lower etch rate for state S0, and the size of the predetermined gap for state S1 is less than that for state S1 Helping to achieve an impedance to achieve a higher etch rate than the rate. As another example, the size of the predetermined gap for state S0 helps achieve the impedance to achieve a higher deposition rate for state S0, and the size of the predetermined gap for state S1 is higher for state S1 Lt; RTI ID = 0.0 > deposition rate. &Lt; / RTI > As another example, the size of the predetermined gap for state S0 helps to achieve the impedance to achieve more deposition rate for state S0, and the size of the predetermined gap for state S1 is greater than the etch rate for state < RTI ID = 0.0 & Thereby helping to achieve impedance. The deposition rate is the rate at which materials, e.g., masks, oxides, polymers, etc., are deposited on the workpiece 324, and the etch rate is the rate at which the material on the workpiece 324 is etched away.

The size of the gap for state S1 is associated with a portion of the parameter signal sent by gap driver GDS1 (Fig. 7) to operate motor 136 during state S1, and the size of the gap for state S0 is associated with state S0 Is associated with the remaining portion of the parameter signal transmitted to the motor 136 by the gap driver GDSO (Fig. 7).

The gap processor 130 sends a feedback signal indicating this to the phase delay circuit 138 when it is determined that the magnitude of the measured gap does not match the magnitude of the predetermined gap for the state. Upon receipt of a signal indicating that the magnitude of the measured gap does not match the magnitude of the predetermined gap for the current state during the current state, e.g., state S0, state S1, etc., For example, it increases the phase delay for state S1, state S0, etc. following the current state. The phase delay for the next state is increased relative to the phase delay for the current state and added to the digitally pulsed signal 326 to produce a modified pulsed signal 368. [ For example, when the phase delay circuit 138 transmits a portion of the modified pulsed signal 368 for state S1 to the x MHz RF generator, the y MHz RF generator, and the z MHz RF generator for one cycle, The circuit 138 is configured to receive the remaining portion of the modified pulsed signal 368 for state S0 upon receipt of a signal indicating that it does not match the size of the predetermined gap for state S1, Generator, and z MHz RF generator. As another example, when the phase delay circuit 138 transmits a portion of the modified pulsed signal 368 for state S0 to the x MHz RF generator, the y MHz RF generator, and the z MHz RF generator for one cycle, The circuit 138 is configured to receive the remaining portion of the modified pulsed signal 368 for state S1 upon receipt of a signal indicating that it does not match the size of the predetermined gap for state S0, Generator, and z MHz RF generator.

On the other hand, when it is determined that the magnitude of the measured gap matches the magnitude of the predetermined gap for the state, the gap processor 130 sends a feedback signal indicative thereof to the phase delay circuit 138. During the current state, upon receipt of a signal indicating that the magnitude of the measured gap matches the magnitude of the predetermined gap for the current state, the phase delay circuit 138 does not add any additional delay as compared to the current state, To the x ㎒ RF generator, the y ㎒ RF generator, and the z ㎒ RF generator, a portion of the modified pulsed signal 368. For example, when transmitting a portion of the modified pulsed signal 368 for state S1 to the x MHz RF generator, the y MHz RF generator, and the z MHz RF generator for one cycle, the phase delay circuit 138 may measure The remaining portion of the modified pulsed signal 368 for state S0 upon receipt of a signal indicating that the size of the gap matches the size of the predetermined gap for state S1 is fed to the x MHz RF generator, the y MHz RF generator, And the z MHz RF generator.

As another example, after the pressure in the volume 382 of the plasma chamber 308 has changed, the pressure sensor 416 measures the pressure of one or more gases and / or plasma in the volume 308. The magnitude of the measured pressure is provided to the pressure processor 140 by a pressure sensor 416. The pressure processor 140 determines whether the magnitude of the pressure matches the magnitude of the predetermined pressure for the condition. The magnitude of the predetermined pressure for the state is stored in the memory device (FIG. 7) of the pressure control system 364. Within the memory device, the magnitude of the predetermined pressure for the state is related to the amount of impedance of the plasma in the plasma chamber 308. [ For example, the magnitude of the predetermined pressure for state S1 is associated with the amount of impedance Z1, and the magnitude of the predetermined pressure for state SO is related to the amount of impedance Z2. The magnitude of the pressure for state S1 is associated with a portion of the parameter signal transmitted by pressure controller PCS1 (Fig. 7) to operate motor 144 during state S1, and the magnitude of the pressure for state S0 is associated with state S0 Is associated with the remainder of the parameter signal transmitted to motor 144 by pressure controller PCS0 (Figure 7).

The impedance of the plasma within the plasma chamber 308 is achieved for the state to further achieve an etch rate or deposition rate for the state. For example, the magnitude of the predetermined pressure for state S0 helps achieve the impedance to achieve a lower etch rate for state S0, and the magnitude of the predetermined pressure for state S1 is less than that for state S1 Helping to achieve an impedance to achieve a higher etch rate than the rate. As another example, the magnitude of the predetermined pressure for state S0 helps achieve the impedance to achieve a higher deposition rate for state S0, and the magnitude of the predetermined pressure for state S1 is higher for state S1 Lt; RTI ID = 0.0 > deposition rate. &Lt; / RTI > As another example, the magnitude of the predetermined pressure for state S0 helps achieve the impedance to achieve more deposition rate for state S0, and the magnitude of the predetermined pressure for state S1 is greater than the etch rate for state < RTI ID = 0.0 & Thereby helping to achieve impedance.

When it is determined that the magnitude of the measured pressure does not match the magnitude of the predetermined pressure for the state, the pressure processor 140 sends a feedback signal indicative thereof to the phase delay circuit 138. During the current state, upon receipt of a signal indicating that the magnitude of the measured pressure does not match the magnitude of the predetermined pressure for the current state, the phase delay circuit 138 includes an x MHz RF generator, a y MHz RF generator, Increases the phase delay of a portion of the pulsed digital signal 326 for the next state to produce a modified pulsed signal 368 to be transmitted to the generator. On the other hand, when it is determined that the magnitude of the measured pressure matches the magnitude of the predetermined pressure for the state, the pressure processor 140 sends a feedback signal indicative thereof to the phase delay circuit 138. During the current state, upon receipt of a signal indicating that the magnitude of the measured pressure matches the magnitude of the predetermined pressure for the current state, the phase delay circuit 138 does not add any delay to the pulsed digital signal 326, MHz RF generator, a y ㎒ RF generator, and a z ㎒ RF generator to transmit a portion of the pulsed digital signal 326 for the next state.

The flow sensor 414 measures the flow rate of one or more process gases flowing from the gas source GS to the plasma chamber 308. In another example, The amount of flow rate measured is provided to flow processor 146 by flow sensor 414. The flow processor 146 determines whether the amount of the flow rate matches the amount of the predetermined flow rate for the state. The amount of the predetermined flow rate for the state is stored in the memory device (FIG. 7) of the flow control system 366. Within the memory device, the amount of the predetermined flow rate for the state is related to the amount of impedance of the plasma in the plasma chamber 308. [ For example, the amount of the predetermined flow rate for state S1 is associated with the amount of impedance Z1, and the amount of the predetermined flow rate for state S0 is associated with the amount of impedance Z2. The amount of flow rate for state S1 is associated with a portion of the parameter signal sent by flow driver FDS1 (Fig. 7) to operate motor 150 during state S1, and the amount of flow rate for state S0 is associated with state S0 Is associated with the remainder of the parameter signal transmitted to the motor 150 by the flow driver FDSO (Fig. 7).

The impedance of the plasma in the plasma chamber 308 is achieved for the state to further achieve an etch rate or deposition rate for the state. For example, the amount of the predetermined flow rate for state S0 helps achieve the impedance to achieve a lower etch rate for state S0, and the amount of the predetermined flow rate for state S1 is less than that for state S1 Helping to achieve an impedance to achieve a higher etch rate than the rate. As another example, the amount of the predetermined flow rate for the state S0 helps achieve the impedance to achieve a higher deposition rate for the state S0, and the amount of the predetermined flow rate for the state S1 is higher for the state S1 Lt; RTI ID = 0.0 > deposition rate. &Lt; / RTI > As another example, the amount of the predetermined flow rate for state S0 helps achieve the impedance to achieve a further deposition rate for state S0, and the amount of the predetermined flow rate for state S1 is greater than the etch rate for state S1 Thereby helping to achieve impedance.

The flow processor 146 sends a feedback signal indicative thereof to the phase delay circuit 138 when it is determined that the amount of the measured flow rate does not match the amount of the predetermined flow rate for the state. During the current state, upon receipt of a signal indicating that the amount of the measured flow rate does not match the predetermined amount of flow rate for the current state, the phase delay circuit 138 includes an x MHz RF generator, a y MHz RF generator, and z To add a phase delay to a portion of the pulsed digital signal 326 for the next state to produce a modified pulsed signal 368 to be transmitted to the RF generator. On the other hand, when it is determined that the amount of the measured flow rate matches the amount of the predetermined flow rate for the state, the flow processor 146 sends a feedback signal indicative thereof to the phase delay circuit 138. During the current state, upon receipt of a signal indicating that the amount of the measured flow rate matches the amount of the predetermined flow rate for the current state, the phase delay circuit 138 adds no delay to the pulsed digital signal 326 And transmits a portion of the pulsed digital signal 326 for the next state to the x ㎒ RF generator, the y ㎒ RF generator, and the z ㎒ RF generator.

In various embodiments, the feedback signals generated in the gap processor 130, the WAP processor 140, and the flow processor 146 are fed to the digital pulsed signal 326 generated by the x MHz RF generator and the modified pulsed Signal 368. < / RTI >

In various embodiments, the phase delay circuit 138 adds a phase delay to the digital pulsed signal 326, and the phase delay is determined by the response time of the gap control mechanical components, the response time of the pressure control mechanical components, It is determined to compensate for the slowest response time among the response times of the components. For example, the phase delay added by the phase delay circuit 138 may match or exceed the response time of the gap control mechanical components, the response time of the pressure control mechanical components, and the response time of the flow control mechanical components, do. As another example, a signal indicating that the gap measured by the gap sensor 412 does not match a predetermined gap for the state, the pressure measured by the pressure sensor 416 does not match the magnitude of the predetermined pressure for the condition And upon receipt of a signal indicating that the flow rate measured by the flow sensor 414 does not match the amount of the predetermined flow rate for the state, the phase delay circuit 138 will determine a predetermined gap The time to achieve the magnitude of the predetermined pressure, and the amount of the longest time to achieve the predetermined amount of flow rate. The phase delay circuit 138 includes a time delay to obtain a predetermined magnitude of the gap from the memory device of the phase delay circuit 138, a time to achieve a predetermined magnitude of pressure for the state, And accesses the time to achieve the determined amount of flow rate. The phase delay circuit 138 determines that the remaining time of the digital signal 326 pulsed by the time for achieving a predetermined amount of flow for the state Delay the part. Similarly, when it is determined that the time for achieving a predetermined magnitude of pressure for the state is the longest, the phase delay circuit 138 generates a digital signal 326 pulsed for a time to achieve a predetermined magnitude of pressure for the state &Lt; / RTI > Similarly, when it is determined that the time to achieve a predetermined gap size for the state is the longest, the phase delay circuit 138 is configured to delay the digital signal pulsed by the time to achieve a predetermined gap size for the state Lt; RTI ID = 0.0 > 326 < / RTI >

In various embodiments, the phase delay circuit 138 includes a processor.

In some embodiments, the response time of the mechanical components, e.g., gap control mechanical components, or pressure control mechanical components, or flow control mechanical components, etc., is determined by the response time of one of the mechanical components, And the sum of one or more response times corresponding to the remaining mechanical components. For example, in the group of two mechanical components, for example, two gap control mechanical components, or two pressure control mechanical components, or two flow control mechanical components, etc., two mechanical components The response time is the sum of the response time of the first mechanical component of the two mechanical components and the response time of the second mechanical component of the two mechanical components.

In various embodiments, the response times of the mechanical components, including the gap control mechanical components, the pressure control mechanical components, and the flow control mechanical components, may be the same as the first mechanical component of the mechanical components, The highest response time among the above response times. For example, in the group of two mechanical components, for example, two gap control mechanical components, or two pressure control mechanical components, or two flow control mechanical components, etc., two mechanical components The response time is greatest between the response time of the first mechanical component of the two mechanical components and the response time of the second mechanical component of the two mechanical components.

In some embodiments, the phase delay circuit 138 is implemented within the host system 312 (FIG. 6B).

In various embodiments where three states are used, gap control system 362 includes three gap drivers, one for each of states S2, S3, and S4, instead of two. In addition, in these embodiments, the WAP control system 364 includes three pressure controls, one for each of the states S2, S3, and S4, instead of two. Also, in these embodiments, the flow control system 366 includes three flow drivers, one for each of the states S2, S3, and S4. During state S2, the gap processor 130 sends a signal to the gap driver dedicated for state S2 to control the motor 136 to also control the position of the top electrode 134. [ Further, during state S3, the gap processor 130 sends a signal to the gap driver dedicated for state S3 to control the motor 136 to also control the position of the top electrode 134. [ During state S4, the gap processor 130 sends a signal to the gap driver dedicated for state S4 to control the motor 136 to also control the position of the upper electrode 134. During state S2, the WAP processor 140 sends a signal to the pressure control dedicated for state S2 to control the motor 144 to also control the vertical positions of the confinement rings 142. Further, during state S3, the WAP processor 140 sends a signal to the dedicated pressure control for state S3 to control the motor 144 to also control the vertical positions of the confinement rings 142. During state S4, the WAP processor 140 sends a signal to the pressure control dedicated for state S4 to control the motor 144 to also control the vertical positions of the confinement rings 142. Similarly, during state S2, the flow processor 146 sends a signal to the flow driver dedicated to state S2 to control the motor 150 to also control the opening or closing of the valve 148. Further, during state S3, the flow processor 146 sends a signal to the flow driver dedicated to state S3 to control the motor 150 to also control the opening or closing of the valve 148. During state S4, the flow processor 146 sends a signal to the flow driver dedicated to state S4 to control the motor 150 to also control the opening or closing of the valve 148.

Note that, in some embodiments, instead of controlling the position of the confinement rings 142 vertically up and down, the motor is controlled by the WAP controllers and the WAP processor 140 to control the opening and closing of the confinement rings Should be. The opening and closing is done to control the pressure in the plasma chamber 308.

In some embodiments, different phase delays are applied to different RF generators. For example, a first phase delay is applied to the x MHz RF generator and a second phase delay is applied to the y MHz RF generator. The first phase delay circuit for applying the first phase delay is coupled between the host system 312 and the x ㎒ RF generator and the second phase delay circuit for applying the second phase delay is coupled between the host system 312 and the y MHz RF generator. The first phase delay circuit receives the digitally pulsed signal 326 from the host system 312 and provides a digital pulsed signal 326 to generate a modified pulsed signal 368 to provide to the x- The phase is delayed by the first phase delay. The x MHz RF generator receives the modified pulsed signal 368 and generates an RF signal in synchronization with the modified pulsed signal 368. In addition, the second phase delay circuit receives the digitally pulsed signal 326 from the host system 312 and generates a digital pulsed signal 326 to generate another modified pulsed signal to provide to the y ㎒ RF generator. The phase is delayed by the second phase delay. The y MHz RF generator receives another modified pulsed signal and generates an RF signal in synchronization with the other modified pulsed signal.

9 is a diagram of an embodiment of a tri-state pulsed signal used to generate three states S2, S3, and S4. The three states (S2, S3, and S4) repeat every clock cycle. Each of states S2, S3, and S4 is shown occupying 33% of the duty cycle. In some embodiments, each of states S2, S3, and S4 occupies a portion of the duty cycle that differs from 33%. For example, state S2 occupies 20% of the duty cycle, state S3 occupies 50% of the duty cycle, and state S4 occupies 30% of the duty cycle. As another example, state S2 occupies 40% of the duty cycle, state S3 occupies 10% of the duty cycle, and state S4 occupies 50% of the duty cycle.

The 3-state pulsed signal is generated by a clock source, e.g., a crystal oscillator, or by a computer, and the signal 326 (Figs. 6A, 6B, 7, Y, and z MHz RF generators instead of providing them to the RF generator, the y MHz RF generator, the z MHz RF generator, the gap control system 362, the pressure control system 364, and / or the flow control system 366 &Lt; / RTI > 1c-2), or graph a9 (Fig. 1c-2), or graph a12 (Fig. 1c-2) 1d-2), or the graph a13 (Fig. 1d-2). Likewise, upon receipt of the tri-state pulsed signal, either the x MHz RF generator, the y MHz RF generator, or the z MHz RF generator are shown in graph b8 (Figure 2c-2), or graph b9 (Figure 2c-2) Or graph b12 (Fig. 2d-2), or graph b13 (Fig. 2d-2). In addition, upon receipt of the tri-state pulsed signal, either the gap control system 362, the pressure control system 364, and the flow control system 366 may be used to generate a graph a8 (FIG. 1C-2) 1c-2), or graph a12 (Fig. 1d-2), or graph a13 (Fig. Similarly, on receipt of the tri-state pulsed signal, one of the gap control system 362, the pressure control system 364, and the flow control system 366 may be selected from graph b8 (Fig. 2c-2), or graph b9 2c-2), or graph b12 (Fig. 2d-2), or graph b13 (Fig. 2d-2).

1C-2), graph a9 (FIG. 1C-2), graph a12 (FIG. 1D-2) 2), the graph b13 (Fig. 2), and the graph b13 (Fig. 2 (d-2) And generates RF signals having statistical measurements as illustrated in the combination. Similarly, in some embodiments, the combination of the gap control system 362, the pressure control system 364, and the flow control system 366 upon receipt of the tri-state pulsed signal is shown in graph a8 (FIG. &Lt; RTI ID = , Graph a9 (FIG. 1C-2), graph a12 (FIG. 1D-2), graph a13 (FIG. 1D-2), graph b8 2d-2), and graph b13 (Fig. 2d-2).

In some embodiments, the tri-state pulsed signal is generated by a clock source or by a computer and is coupled to a phase delay circuit 138 (Figs. 6B, 7, and 8) to generate a delayed tri- . The delayed tri-state pulsed signal is provided to the x ㎒ RF generator, the y ㎒ RF generator, and the z ㎒ RF generator. Upon receipt of the delayed tri-state pulsed signal, the x ㎒ RF generator, the y ㎒ RF generator, and the z ㎒ RF generator generate RF signals that synchronize with the tri-state pulsed signal.

In various embodiments, the tri-state pulsed signal may be generated by a clock source or by a computer and may be generated by a gap processor 130 (Figs. 6B, 7 and 8), a WAP processor 140 (Fig. 6B, 7, and 8), and flow processor 146 (FIGS. 6B, 7, and 8). Upon receipt of the tri-state pulsed signal, gap processor 130 and flow processor 146 control corresponding motors 136 and 150 via corresponding drivers for states S2, S3, and S4, respectively . In addition, upon receipt of a tri-state pulsed signal, the WAP processor 140 controls the motor 144 via a corresponding control for each of states S2, S3, and S4.

In some embodiments, two digital clock sources, e.g., processors, computers, crystal oscillators and analog-to-digital converters, etc., are used to generate a tri-state pulsed signal. The first clock signal of the first digital clock source of the digital clock sources has states 1 and 0 and the second clock signal of the second digital clock source of the digital clock sources has states 1 and 0. An adder, e. G., An adder circuit, is coupled to the two digital clock sources to sum the first digital signal and the second digital signal to produce a pulsed signal having three states. The adder may be configured to provide a tri-state pulsed signal to the x MHz RF generator, and / or the y MHz RF generator, and / or the z MHz RF generator, and / or the phase delay circuit 138, and / or the gap control system 362, And / or the y MHz RF generator, and / or the z MHz RF generator, and / or the phase delay circuit (s) 366 to provide the RF signal to the pressure control system 364 and / 138 and / or gap control system 362, and / or pressure control system 364, and / or flow control system 366.

10 is a graph 380 for illustrating the group phase delay of the first and second variables in comparison to the phase of pulsed signal 326. FIG. The graph 380 plots the magnitude of the signal on the y-axis versus time t on the x-axis. Graph 380 plots the first variable on the y-axis for time. The first variable is shown as signal 384. The graph 380 also plots the second variable on the y-axis for time t. The second variable is shown as signal 386.

It should be noted that the graph 380 is not shown to scale. For example, although signals 326, 368, 384, and 386 are shown to have approximately the same magnitude at some time, the magnitude of any of the signals 326, 368, 384, Signals 326, 368, 384, and 386.

After the group phase delay, for example, a phase delay < RTI ID = 0.0 > φd, < / RTI > etc. is applied to the phase delay circuit 138 (e. G., To generate a modified pulsed signal 368) applied to the x-, (Fig. 6B, Fig. 7, and Fig. 8). Any two of the x, y, and z MHz RF generators generate two RF signals with signals 384 and 386 as statistical measurements of the RF signals. The two RF signals provided by two generators, the x ㎒ RF generator, the y ㎒ RF generator, and the z ㎒ RF generator, are generated after group phase delay or group phase delay.

Graph 380 shows signals 384 and 386 for any two of the x ㎒ RF generator, the y ㎒ RF generator, and the z ㎒ RF generator, but in some embodiments, At least one x MHz RF generator, a y MHz RF generator, and a z MHz RF generator.

In some embodiments, signal 384 illustrates a first parameter instead of a first parameter and signal 386 illustrates a second parameter instead of a second parameter.

Although the above embodiments have been described using x, y, and z MHz RF generators, in some embodiments, any other number of RF generators, e.g., two RF generators, one RF generator, 4 RF generators, etc. are used.

Although the above described embodiments have been described with reference to a parallel plate plasma chamber 308, in one embodiment, the embodiments described above may be applied to other types of plasma chambers, for example, an inductively coupled plasma (ICP) , A plasma chamber including an electron-cyclotron resonance (ECR) reactor, or the like. For example, the x, y, and z MHz RF generators are coupled to an inductor in an ICP plasma chamber.

Although the embodiments described above relate to providing an RF signal to the lower electrode of the chuck 132 and to grounding the upper electrode 134, in some embodiments, the RF signal is applied to the lower electrode of the chuck 132 And is provided to the upper electrode 134 while being grounded.

The embodiments described herein may be practiced with various computer system configurations including portable hardware units, microprocessor systems, microprocessor-based or programmable consumer electronics, minicomputers, mainframe computers, and the like. Embodiments may also be practiced in distributed computing environments where tasks are performed by remote processing hardware units linked through a network.

In view of the above embodiments, it will be appreciated that the embodiments may employ various computer-implemented operations involving data stored in computer systems. These operations use physical manipulations of physical quantities. Any of the operations described herein that form part of the embodiments are useful machine operations. Embodiments also relate to a hardware unit or device for performing these operations. The device may be specially configured as a special purpose computer. When specified as a special purpose computer, the computer may also perform other processing, program executions or routines that are not part of a special purpose, but may still operate for a special purpose. In some embodiments, the operations may be processed by a general purpose computer selectively activated or configured by computer memory, one or more computer programs stored in a cache or obtained over a network. When data is acquired over the network, the data may be processed by the cloud of other computers on the network, e.g., computing resources.

One or more embodiments may also be fabricated as non-volatile computer-readable media, e.g., computer readable code on a storage device. A non-temporary computer-readable medium is any data storage hardware unit that is capable of storing data that can be thereafter read by a computer system. Examples of non-volatile computer-readable media include, but are not limited to, hard drives, network attached storage (NAS), read-only memory (RAM), random-access memory (ROM), compact disc-ROMs (CD- CD-recordables), CD-RWs (CD-RWs), magnetic tapes, and other optical and non-optical data storage hardware units. Non-volatile computer-readable media also can include a computer-readable type of medium distributed over network-coupled computer systems in which the computer-readable code is stored and executed in a distributed manner.

While operations are described in a particular order, other management operations may be performed between operations, or operations may be adjusted to occur at slightly different times, or as long as processing of the overlay operations is performed in the desired manner, It will be appreciated that they may be distributed within a system that enables the generation of processing operations at various associated intervals.

One or more aspects from any embodiment may be combined with one or more aspects of any other embodiment without departing from the scope of the various embodiments described in this disclosure.

While the foregoing embodiments have been described in some detail for purposes of clarity of understanding, it will be apparent that certain changes and modifications may be practiced within the scope of the appended claims. Accordingly, the embodiments are to be considered as illustrative and not restrictive, and the embodiments are not limited to the details given herein, but may be modified within the scope and equivalents of the appended claims.

Claims

A master RF generator for generating a first portion of a master RF signal during a first state and a second portion of the master signal during a second state, the master RF signal being a sinusoidal signal, The master RF generator;
An impedance matching circuit coupled to the master RF generator via an RF cable to modify the master RF signal to produce a modified RF signal; And
A plasma chamber coupled to the impedance matching circuit via an RF transmission line, the plasma chamber for generating a plasma based on the modified RF signal,
Wherein the statistical measure of the first portion has a positive slope or a negative slope.

The method according to claim 1,
A slave RF generator for receiving a first portion of the digitally pulsed signal during the first state from the master RF generator and for receiving a second portion of the digitally pulsed signal during the second state from the master RF generator, Further included,
Wherein the slave RF generator is for generating a first portion of a slave RF signal during the first state and generating a second portion of the slave RF signal during the second state,
Wherein the slave signal is a sinusoidal signal,
Wherein the statistical measure of the first portion of the slave RF signal has a positive slope or a negative slope.

3. The method of claim 2,
Wherein the statistical measurement of the first portion of the slave RF signal has a positive slope during at least a portion of time that the statistical measurement of the first portion of the master RF signal has a positive slope.

3. The method of claim 2,
Wherein the statistical measurement of the first portion of the slave RF signal has a negative slope during at least a portion of time that the statistical measurement of the first portion of the master RF signal has a negative slope.

The method according to claim 1,
Wherein the master RF signal has frequency and power.

The method according to claim 1,
Further comprising a gap control system coupled to the master RF generator to generate a first portion of a gap signal during the first state and to generate a second portion of the gap signal during the second state,
Wherein the plasma chamber includes a chuck and an upper electrode facing the chuck,
Wherein the gap control system is further coupled to the upper electrode of the plasma chamber through a motor to change a gap between the upper electrode and the chuck,
Wherein the gap signal has a positive slope or a negative slope.

The method according to claim 6,
Wherein the gap control system includes a gap sensor,
Wherein the gap sensor is for determining a size of the gap between the upper electrode and the chuck.

8. The method of claim 7,
A host controller for generating a pulsed signal; And
A phase delay circuit coupled to the host controller for delaying the phase of the pulsed signal based on the size of the gap, the host system being coupled to the master RF generator through the phase delay circuit, &Lt; / RTI > further comprising a delay circuit.

The method according to claim 1,
Further comprising a pressure control system coupled to the master RF generator to generate a first portion of the pressure signal during the first state and to generate a second portion of the pressure signal during the second state,
Wherein the plasma chamber comprises a plurality of confinement rings,
The pressure control system is further coupled to the confinement rings through a motor to change the pressure in the plasma chamber,
Wherein the first portion of the pressure signal has a positive slope or a negative slope.

10. The method of claim 9,
Wherein the pressure control system includes a pressure sensor,
Wherein the pressure sensor is for determining the magnitude of the pressure in the plasma chamber.

11. The method of claim 10,
A host controller for generating a pulsed signal; And
A phase delay circuit coupled to the host controller for delaying the phase of the pulsed signal based on the magnitude of the pressure, the host controller coupled to the master RF generator via the phase delay circuit, &Lt; / RTI > further comprising a delay circuit.

The method according to claim 1,
Further comprising a flow control system coupled to the master RF generator to generate a first portion of the flow signal during the first state and to generate a second portion of the flow signal during the second state,
The flow control system is further coupled to the valve via a motor to control a flow rate of gas to the plasma chamber,
Wherein the first portion of the flow signal has a positive slope or a negative slope.

13. The method of claim 12,
The flow control system includes a flow sensor,
Wherein the flow sensor is for determining an amount of flow of one or more gases in the plasma chamber.

14. The method of claim 13,
A host controller for generating a pulsed signal; And
A phase delay circuit coupled to the host controller for delaying the phase of the pulsed signal based on an amount of the flow, the host controller being coupled to the master RF generator via the phase delay circuit, &Lt; / RTI > further comprising a delay circuit.

The method according to claim 1,
Wherein the first state is a high state and the second state is a low state.

The method according to claim 1,
Wherein the first state is opposite to the second state.

The method according to claim 1,
Wherein the impedance matching circuit modifies the master RF signal by matching an impedance of a load coupled to the impedance matching circuit to an impedance of a source coupled to the impedance matching circuit.

The method according to claim 1,
Wherein the statistical measurement comprises a root mean square (RMS) value, or an average value, or an intermediate value, or a peak-to-peak amplitude, or a zero-to-peak amplitude, or a combination thereof.

The method according to claim 1,
Wherein each of the positive slope and the negative slope is non-zero and finite.

Generating a first portion of the master RF signal during a first state and generating a second portion of the master signal during a second state;
Matching an impedance of the source and the load based on the master RF signal to generate a modified RF signal, the source comprising an RF generator and an RF cable, the load comprising an RF transmission line and a plasma chamber , Matching the impedance; And
And receiving the modified RF signal to generate a plasma in the plasma chamber,
Wherein the statistical measure of the first portion has a positive slope or a negative slope.

21. The method of claim 20,
Wherein the statistical measurement comprises an RMS value, or an average value, or an intermediate value, or a peak-to-peak amplitude, or a zero-to-peak amplitude, or a combination thereof.

A first RF generator for generating a first portion of a first RF signal during a first state and generating a second portion of the first RF signal during a second state wherein the first RF signal is a sinusoidal signal, A first RF generator,
Wherein the first RF generator is coupled to an impedance matching circuit coupled to the plasma chamber,
Wherein the statistical measure of the first portion of the first RF signal has a positive slope or negative slope.

23. The method of claim 22,
A second RF generator for generating a first portion of a second RF signal during a first state and for generating a second portion of the second RF signal during a second state wherein the second RF signal is a sinusoidal signal, A second RF generator,
The second RF generator is coupled to the impedance matching circuit via an RF cable,
Wherein the statistical measurement of the first portion of the second RF signal has a positive slope or a negative slope.