JP6180890B2 - Plasma processing method - Google Patents

Description

  The present invention relates to a plasma processing method using a plasma processing apparatus.

  One of plasma processing apparatuses currently used for mass production of semiconductor devices is an electron cyclotron resonance (hereinafter abbreviated as ECR) type dry etching apparatus. This plasma dry etching system applies a magnetic field to the plasma generation space into which the reaction gas is introduced, and sets the magnetic field strength so that the microwave frequency and the electron cyclotron frequency resonate. It has the feature that it can generate high density plasma efficiently. For example, when manufacturing a semiconductor device, in order to accelerate ions incident on a sample such as a semiconductor substrate on which a film to be processed is formed, high-frequency power is applied to the sample as a sine wave in a continuous waveform. In addition, halogens such as chlorine and fluorine are widely used as a reaction gas that becomes plasma.

  With the recent miniaturization of semiconductor devices, the thickness of the gate oxide film has become 2 nm or less. Therefore, it is necessary to improve the controllability of the plasma etching process and the etching selectivity of the silicon film with respect to the gate oxide film. In addition, since the wafer diameter is increasing, it is necessary to improve the uniformity of processing accuracy in the wafer surface at the same time.

  As one of the techniques for realizing high-precision plasma etching, there is a plasma etching method using pulse discharge. For example, Patent Document 1 discloses that a high-frequency bias applied to a wafer at the same time as time modulation of plasma generation power is timed. A method of preventing dielectric breakdown of an oxide film on a processing wafer by controlling the temperature of electrons in the plasma by synchronizing with the on / off of the modulated plasma is disclosed.

  Patent Document 2 discloses a method for controlling the reaction product and improving the etching processing accuracy by time-modulating the plasma generation power and the high frequency bias.

Japanese Patent Laid-Open No. 9-092645 JP-A-8-250479

  As described in the “Background Art” in the previous section, the first high-frequency power (hereinafter referred to as S-RF) for generating plasma and the energy control of ions incident on the sample to be processed are used. In a plasma processing apparatus that uses two frequencies of second high-frequency power (hereinafter referred to as W-RF), time-modulating S-RF and W-RF is effective in improving process performance. In particular, time-modulated W-RF is effective in improving shape controllability in microfabrication because the ratio between active species deposition and ion incidence can be controlled independently of plasma generation conditions.

  However, it has been found that when time-modulated W-RF is applied, it is difficult to improve the in-wafer uniformity of the etching rate and the etching shape. This is because the etching rate varies and the in-plane distribution varies due to the modulation of the output of the W-RF. Furthermore, when W-RF modulation is extreme, charging damage to the semiconductor device may occur.

  The present invention has been made in view of the above problems, and aims to realize a plasma processing method using time-modulated S-RF and time-modulated W-RF, which is excellent in the in-plane uniformity of the etching rate and etching shape. It is what.

In order to solve the above problems, for example, the configuration and processing procedure described in the claims are adopted.
The present application includes a plurality of means for solving the above-described problems. For example, a vacuum container in which plasma is generated, a first high-frequency power source that supplies a first high-frequency power for generating the plasma, In a plasma processing method for plasma-treating the object to be processed using a plasma processing apparatus comprising a second high-frequency power source for supplying a second high-frequency power to a sample stage on which the object to be processed is placed,
When n is a natural number and the frequency of the first pulse for pulse modulation of the first high-frequency power is n times the frequency of the second pulse for pulse modulation of the second high-frequency power,
The first high-frequency power and the second high-frequency power so that the ON period of the second pulse includes an ON period of n first pulses and an OFF period of n−1 first pulses. The plasma processing method is characterized in that each of these is pulse-modulated.

In addition, a vacuum vessel in which plasma is generated, a first high-frequency power source that supplies a first high-frequency power for generating the plasma, and a second high-frequency wave on a sample stage on which the object to be processed is placed In a plasma processing method for plasma processing the object to be processed using a plasma processing apparatus including a second high frequency power source for supplying electric power,
When n is a natural number and the frequency of the first pulse for pulse modulation of the first high-frequency power is n times the frequency of the second pulse for pulse modulation of the second high-frequency power,
n-1 + (duty ratio of the first pulse generator for pulse modulation of the first high-frequency power) <n × (duty ratio of the second pulse generator for pulse modulation of the second high-frequency power)
It is set as the plasma processing method characterized by these.

In addition, a vacuum container in which plasma is generated, a first high-frequency power source that supplies a first high-frequency power for generating the plasma, and a second that is used for energy control of ions incident on the sample to be processed In a plasma processing method for plasma processing the object to be processed using a plasma processing apparatus having a high frequency power source,
Each output of the first high-frequency power source and the second high-frequency power source is time-modulated synchronously,
The output of the first high-frequency power supply is turned on / off within a period during which the output of the second high-frequency power supply is on, and is turned off within a period during which the output of the second high-frequency power supply is off. This is a plasma processing method.

  According to the present invention, it is possible to provide a plasma processing method using a time-modulated S-RF and a time-modulated W-RF, which are excellent in uniformity of an etching rate and an etched shape within a wafer surface.

First high-frequency power output (source power: S-RF) used for plasma generation, including the time of initial rise and the time of final fall in the plasma processing method according to the embodiment of the present invention, and ion incidence on a sample to be processed It is an example of the timing chart of the 2nd high frequency power supply output (bias electric power: W-RF) which controls energy. Surface of etching rate under conditions (A) where plasma is generated by S-RF and W-RF is not applied and conditions (B) where plasma is generated by S-RF and W-RF is applied It is a comparison figure of internal distribution. It is the schematic of the plasma etching apparatus used when implementing the plasma processing method which concerns on the Example of this invention. It is a schematic block diagram of the time modulation control unit in the plasma etching apparatus shown in FIG. The first high-frequency power output (source power) and the second high-frequency power output {bias power} are synchronized, and the duty ratio of the second high-frequency power output is larger than the duty ratio of the first high-frequency power output. It is a timing chart of the 1st high frequency power output and the 2nd high frequency power output in the case (example of the present invention). It is a comparison figure of in-plane distribution of an etching rate, (a) is a duty ratio of S-RF, and a duty ratio of W-RF is 100% (continuous wave), (b) is a duty of S-RF. When the ratio is larger than the duty ratio of W-RF, (c) shows the case where the duty ratio of S-RF is smaller than the duty ratio of W-RF (an embodiment of the present invention). Timing chart of the first high-frequency power output and the second high-frequency power output when the duty ratio between the first high-frequency power output (source power) and the second high-frequency power output (bias power) is 100% It is. The first high-frequency power output (source power) and the second high-frequency power output (bias power) are synchronized, and the first high-frequency power output duty ratio is larger than the second high-frequency power output. It is a timing chart of 1 high frequency power output and the 2nd high frequency power output. It is a timing chart of the 1st high frequency power supply output (source power) and the 2nd high frequency power supply output when the 2nd high frequency power supply output (bias power) does not become zero at the time of low output. The first high-frequency power output when the repetition frequency of the first high-frequency power output (source power) is an integral multiple of the repeated output of the second high-frequency power output (bias power) (another example of the present invention) FIG. 6 is a timing chart of a second high-frequency power output. 6 is a timing chart of a first high-frequency power output (source power) and a second high-frequency power output (bias power) when time modulation control is performed from the initial rise (another example of the present invention). Timing chart of the first high-frequency power output (source power) and the second high-frequency power output (bias power) when the second high-frequency power output is increased in multiple steps (another example of the present invention) It is.

  Hereinafter, the present invention will be described in detail by way of examples. In the embodiment, dry etching is described as an example of plasma treatment, but the present invention is not limited to this.

  First high-frequency power output (source power: S-RF) used for plasma generation, including the time of initial rise and the time of final fall in the plasma processing method according to the embodiment of the present invention, and ion incidence on a sample to be processed An example of a timing chart of the second high-frequency power output (bias power: W-RF) for controlling energy is shown in FIG. In this embodiment, the time modulation and on / off of the output are controlled so that the source power supply is always turned on during the period when the bias power supply is on. A method for implementing such timing control will be described later.

  Etching rates under the conditions where plasma is generated by S-RF and W-RF is not applied (condition A) and conditions where plasma is generated by S-RF and W-RF is applied (condition B) As a result of evaluating the in-plane distribution, the following findings were obtained. As shown in FIG. 2, in the condition A, the wafer central portion has a high etching rate distribution, but in the condition B, the etching rate distribution is uniform in the plane, and there is a difference in the etching rate distribution in each condition. This phenomenon can be considered as follows.

  Since the etching rate distribution has a high correlation with the plasma density distribution, it is considered that the plasma density distribution was different in each of the conditions A and B. That is, under condition A, the plasma density was high at the center, and under condition B, the plasma density was relatively uniform. The closer the W-RF frequency is to the S-RF frequency, the easier the W-RF gives energy to the generated plasma, and the density distribution of the plasma changes under the influence of the electric field of the W-RF. That is, there is a difference in density distribution between plasma generated only by S-RF and plasma generated by combining S-RF and W-RF. If there is a transition from the condition A state to the condition B state, the in-plane distribution of the plasma density changes at that moment. Therefore, it can be said that the fluctuation of the plasma density distribution does not occur unless the state transition from the condition A to the condition B or the state transition from the condition B to the condition A occurs.

  In order to prevent the state transition from the condition A to the condition B or the state transition from the condition B to the condition A, the S-RF is output within the period during which the W-RF is output. It is thought that plasma should be generated. For example, if the time modulation timings of S-RF and W-RF are completely synchronized, the state transition from condition A to condition B does not occur. However, in actuality, an error occurs in the modulation timing, so that it cannot be completely synchronized and a state transition occurs with a certain probability. Therefore, in consideration of the modulation timing error, a sufficient margin is secured and the S-RF is output within the period in which the W-RF is output.

  FIG. 3 shows a basic configuration of a plasma processing apparatus used for carrying out a plasma processing method according to an embodiment of the present invention. The basic configuration of the plasma processing apparatus will be described with reference to FIG. FIG. 3 is a cross-sectional view of a parallel plate type plasma etching apparatus. However, the configuration of the plasma processing apparatus for carrying out the plasma processing method according to the present embodiment is not limited to the parallel plate type, and it is sufficient that two or more high-frequency power sources are provided. In this embodiment, one high-frequency power source 113, 114 is disposed on each of the parallel plate upper and lower electrodes 102, 106, but the same effect can be obtained even if two or more power sources are disposed on the same electrode. . A grounded cylindrical etching processing chamber 107 made of a conductive material such as aluminum is provided with a planar antenna (upper electrode) 102, a shower plate 103, a wafer 105, and a processing table (lower electrode) 106 therein. ing. The planar antenna 102 is made of a conductive material, such as aluminum, and is separated from a grounded processing chamber outer wall by an insulating film such as ceramic. VHF band electromagnetic waves generated by the first high-frequency power source 113, for example, 200 MHz, are guided to the planar antenna 102 through the first matching unit 111, and the reaction gas in the processing chamber 107 introduced from the gas inlet 101 is turned into plasma. To do. A high frequency (for example, 4 MHz) generated by the second high frequency power supply 114 is guided to the processing stage 106 via the second matching unit 112, and a bias is applied to the wafer 105. The ions of the plasma 104 generated by the high frequency guided from the planar antenna 102 contribute to the etching reaction together with radicals attached to the wafer 105 while the energy is controlled according to the electric power applied to the wafer 105.

As the etching species, any charged species and neutral particles emitted from the plasma can be used. For example, Cl ₂ , HBr, O ₂ , N ₂ , He, Ar, Kr, and fluorocarbon can be used as the reaction gas. In this example, HBr, O ₂ and Ar were used as the reaction gas. Reference numeral 108 denotes a vacuum exhaust pump, and reference numeral 109 denotes a control unit.

  FIG. 4 shows a schematic configuration of a control unit for time modulation of high frequency power in the plasma etching apparatus shown in FIG. As shown in FIG. 4, the repetition frequency, duty ratio, and delay time (t1, t2, T1, T2) input to the personal computer 301 are processed as digital signals and converted into analog signals via the D / A converter 302. It is converted and transmitted to the A / D converter 305. The repetition frequency refers to the number of repetitions per unit time of a period during which high-frequency power is applied (on period) and a period during which no high frequency power is applied (off period). Point to. The analog signal received by the A / D converter 305 is converted into a digital signal, processed by the reference signal generator 306, and the time modulation (TM) basic signal is converted into an S-RF signal generator 307 and a W-RF signal generator. Output to 308. In addition, high-frequency source power (S-RF) and high-frequency bias power (W-RF) are output from the first high-frequency power source 113 and the second high-frequency power source 114 by the digital signal output from the A / D converter 305, respectively. .

  The S-RF signal generator 307 outputs the pulse waveform 1 delayed by the delay circuit 309 by the delay time t1 of the duty ratio set with the TM basic signal and rising. The W-RF signal generator 308 outputs a pulse waveform 2 having a set duty ratio that is synchronized with the TM basic signal. Note that the fall of the pulse waveform 2 is delayed by the delay circuit 310 from the fall of the pulse waveform 1 by t2. The pulse waveform 1 is superimposed on the output high-frequency source power, and the time-modulated high-frequency power (S-RF) is supplied from the first high-frequency power source 113 to the planar antenna 2. Further, the pulse waveform 2 is superimposed on the output high-frequency bias power, and the time-modulated high-frequency power (W-RF) is supplied from the second high-frequency power source 114 to the processing table 106. The repetition frequency of the reference signal generator 306 is used in the range of 50 Hz to 10 kHz. Further, the duty ratio of the control unit 109 is used in the range of 5 to 95%. Although the pulse waveforms 1 and 2 are not shown, they can be approximated by waveforms corresponding to the source power and the bias power in FIG. 5, for example.

  In the present invention, the frequency of the TM basic signal is not particularly limited, but is set to 100 Hz in this embodiment. In this embodiment, the frequencies of S-RF and W-RF are 200 MHz and 4 MHz, respectively. Moreover, the frequency of S-RF and W-RF is not necessarily limited, but the effect is higher as the ratio of the frequency of S-RF and W-RF is closer to 1, and the effect is clearer within 100 times. In addition, the duty ratio and the delay times t1, t2, T1, and T2 are set so that plasma is generated while a wafer bias is always applied (see FIG. 1). As described above, the duty ratios of the S-RF signal generator 307 and the W-RF signal generator 308 are not limited and may be 5 to 95%. It is necessary to set as “Duty ratio of W <RF signal generator 308”. Further, the delay time t1 needs to be equal to or less than the difference between the “on time corresponding to the duty ratio of the W-RF signal generator 308” and the “on time corresponding to the duty ratio of the S-RF signal generator 307”. . Ideally, the “duty ratio of the S-RF signal generator 307” and the “duty ratio of the W-RF signal generator 308” may be completely the same, but in general, the power supply always has a finite response time variation. Therefore, the requirement “Duty ratio of S-RF signal generator 307” <“Duty ratio of W-RF signal generator 308” cannot be satisfied unless the response time variation is taken into consideration. Since the response time of the first high frequency power supply 113 and the second high frequency power supply 114 used in this embodiment is 100 μs, the delay time t1 is set to 100 μs.

  FIG. 6 shows the in-plane distribution of the etching rate of polysilicon. 6A shows a case where etching is performed by outputting a continuous wave (hereinafter referred to as CW) without time-modulating both S-RF and W-RF (see FIG. 7). . (B) indicated by □ in FIG. 6 is a case where the duty ratio of S-RF is 60% and the duty ratio of W-RF is 40%, unlike the plasma processing method of the present invention. The output of W-RF varies within the output period (see FIG. 8). (C) shown by Δ in FIG. 6 is etched based on the present embodiment satisfying the requirement of “Duty ratio of S-RF signal generator 307” <“Duty ratio of W-RF signal generator 308”. This is the case (see FIGS. 1 and 5). The result of FIG. 6A shows that the etching rate is constant regardless of the position, and when both S-RF and W-RF are output, the plasma density is uniform in the plane. It is believed that there is. The result of FIG. 6B shows that the etching rate is higher at the center. Although it is considered that a uniform plasma density distribution is obtained during the period in which S-RF and W-RF are output simultaneously, the plasma density distribution becomes higher in the center during the period in which only S-RF is output. It is suggested that It is considered that the etching rate distribution shown in FIG. 6B is obtained by averaging the etching rates during the uniform plasma density distribution period and the biased plasma density distribution period. Further, it is considered that the fluctuation of the plasma density distribution is repeatedly generated in a very short time corresponding to the period of time modulation, and there is a concern that the etching shape and charging damage may be affected. On the other hand, the result of FIG. 6C shows that the etching rate is constant regardless of the position. In the plasma processing method of this embodiment, since there is no period in which only S-RF is output, only a uniform plasma density distribution is obtained, and it is considered that the plasma density distribution does not fluctuate during etching. . For this reason, it becomes possible to suppress the charging damage to the process board | substrate (sample) in a semiconductor device manufacturing process.

  Another example will be described with reference to FIG. FIG. 9 shows a case where, in the timing chart shown in FIG. 5, the output (bias power) of the W-RF is larger than zero when the signal output from the W-RF signal generator 308 is off. When the W-RF output is reduced, the etching mode is changed to the deposition mode at a certain threshold. That is, if the W-RF output is zero, it is the deposition mode, but even if the W-RF output is increased to some extent, it is the deposition mode. When the W-RF output is changed within a small range, the manner in which the deposition is applied to the pattern side wall changes with the amount of deposition. For example, assuming L / S (line and space), if the W-RF output is smaller, the pull-in to the bottom is weak, so that it adheres more to the top, but if the W-RF output is larger, the adhered matter moves to the bottom. Many are drawn. Therefore, by controlling the output when the W-RF is turned off at zero or more, it is possible to control the manner of depositing and to perform etching with higher accuracy.

Another example will be described with reference to FIG. FIG. 10 shows a case where the repetition frequency of the signal output from the S-RF signal generator 307 is an integer multiple n of the repetition frequency of the signal output from the W-RF signal generator 308 in the timing chart shown in FIG. . In this case, when n is a natural number and the frequency of the first pulse for pulse modulation of the first high-frequency power is n times the frequency of the second pulse for pulse modulation of the second high-frequency power, the second pulse The first high-frequency power and the second high-frequency power are each pulse-modulated so that the on period includes an on period of n first pulses and an off period of n−1 first pulses. In other words, the following equation is satisfied.
Number 1
n-1 + (Duty ratio of S-RF signal generator 307)
<N × (Duty ratio of W-RF signal generator 308) (1)
Note that equation (1) is derived as follows.
When the period and duty ratio of the signal output from the W-RF signal generator are Tw and Dw, respectively, the ON time of the signal output from the W-RF signal generator is Tw · Dw. On the other hand, when the duty ratio of the signal output from the S-RF signal generator is Ds, the ON time of the signal output from the S-RF signal generator is such that the period of the signal output from the S-RF signal generator is Tw. Since it is / n, Tw · Ds / n. Therefore, the off time of the signal output from the S-RF signal generator is Tw / n−Tw · Ds / n = Tw (1−Ds) / n. In the case where n is a natural number and the frequency of the signal output from the S-RF signal generator is n times the frequency of the signal output from the W-RF signal generator, the present invention provides Tw · Dw> n · Tw · Ds / n + It can be expressed as (n-1) · Tw (1-Ds) / n, and when this equation is arranged, equation (1) is obtained.

  Originally, the frequency of the S-RF and the frequency of the W-RF are not necessarily the same, and it is considered that there is an optimum value for each. By independently determining the S-RF and W-RF frequencies with limitations, the ratio of etching to deposition can be controlled more flexibly.

  The first high-frequency power supply 113 and the second high-frequency power supply 114 require a certain rise time until reaching 100% of the set output at the initial rise. Therefore, if the rise time of each output unit is not taken into consideration, plasma may be generated before the wafer bias is applied. In this embodiment, since a high frequency power source having a rise time of 100 ms or less is used, the delay times T1 and T2 are set to 100 ms, and the S-RF rise timing is set to 100 ms (T1) with respect to the W-RF rise timing. Delayed (see FIG. 1). The TM basic signal was output after the S-RF output reached 100%. Similarly, since a constant fall time is required until the output becomes 0% even when the high frequency power supply falls, the W-RF fall timing is set to 100 ms (T2) with respect to the S-RF fall timing. Delayed. When such an operation is performed, the period during which a wafer bias having a steady-state output (predetermined output) is applied in a state where plasma is not generated can be shortened as much as possible, so that the load on the high-frequency power source can be reduced. Further, since plasma is generated in a state where a wafer bias is applied, fluctuations in the plasma density distribution are sufficiently small. However, if the total ON time of the S-RF (the time from the first ON state to the final OFF state) is set shorter than the total ON time of the W-RF, it is not necessary to set T2. Absent. That is, only T1 needs to be set.

  As shown in FIG. 1, the present invention performs continuous discharge until the output value of S-RF and the output value of W-RF reach a steady state, and pulse-modulates S-RF and W-RF after the steady state. However, as another example, as shown in FIG. 11, the output value of the S-RF and the output value of the W-RF reach the steady state (for example, when S-RF and W-RF rise). May be used to output high-frequency power. Further, the output of the high-frequency power may be lowered while maintaining the TM at the fall. When such an operation is performed, control can be performed without considering the rise time T1 and the fall time T2.

  Another example will be described with reference to FIG. FIG. 12 shows a case in which the W-RF is set to output 100% in two or more stages in the timing chart shown in FIG. For example, first, the W-RF output is increased to 30%, an S-RF rising signal is sent, and then the W-RF output is increased to 100%. When such an operation is performed, the rise time T1 can be set shorter. The same applies to the fall time T2.

  Under the above-mentioned various plasma processing conditions that satisfy the requirement of formula (1), when etching processing of a semiconductor material was performed using a pattern drawn by lithography as a mask, uniformity in the wafer surface was improved in each of the etching rate and the etching shape. We were able to.

  As described above, according to the present embodiment, in plasma etching processing of a semiconductor device or the like that time-modulates the output of S-RF and W-RF, the fluctuation of the plasma density distribution is suppressed, and the wafer surface in each of the etching rate and the etching shape. It becomes possible to improve the internal uniformity. In addition, it is possible to suppress charging damage at the time of manufacturing a semiconductor device.

  Furthermore, by controlling the output of the off time when the W-RF is time-modulated to zero or more, it is possible to control the deposition profile on the pattern sidewall and perform etching with higher accuracy.

  Furthermore, by independently controlling the frequency of S-RF and W-RF, it is possible to improve the in-wafer uniformity of the etching rate and etching shape, and in addition to control the ratio of etching and deposition more flexibly. It becomes possible.

  The present invention relates to a manufacturing apparatus for semiconductor devices and the like, and more particularly to a plasma etching apparatus for performing an etching process of a semiconductor material using a pattern drawn by a lithography technique as a mask. According to the present invention, it is possible to suppress the fluctuation of the plasma distribution, which is a problem in the shape control by the output modulation of the wafer bias power source. As a result, it is possible to realize a plasma processing apparatus capable of improving both the in-wafer uniformity of the shape controllable processing speed and the uniformity of the processing shape.

DESCRIPTION OF SYMBOLS 101 ... Gas inlet, 102 ... Planar antenna, 103 ... Shower plate, 104 ... Plasma, 105 ... Wafer, 106 ... Processing table, 107 ... Etching process chamber, 108 ... Pump, 109 ... Control unit, 111 ... First alignment 112 ... second matching unit 113 ... first high frequency power supply 114 ... second high frequency power supply 301 ... PC personal computer 302 ... D / A converter 305 ... A / D converter 306 ... reference signal generator 307 ... S-RF signal generator, 308 ... W-RF signal generator, 309 ... delay circuit, 310 ... delay circuit.

Claims (11)

Supply and the vacuum vessel flop plasma is generated, the first and the high frequency power source for supplying a first high-frequency power for generating the plasma, a second high-frequency power to the sample stage to the object to be processed is Ru placed in the plasma processing method for processing flop plasma using a plasma processing apparatus and a second high frequency power supply which,
Pulse modulating the first high frequency power with a first pulse;
And a step of pulse-modulating the second high-frequency power with a second pulse,
The duty ratio of the first pulse is smaller than the duty ratio of the second pulse,
The first pulse is turned on when the amplitude of the second pulse is the amplitude of the first period, and is turned off when the amplitude of the second pulse is the amplitude of the second period. Pulse,
The plasma processing method according to claim 1, wherein an amplitude of the first period is larger than an amplitude of the second period . The plasma processing method according to claim 1,
The amplitude of the second period, the plasma processing method characterized by not greater than 0. The plasma processing method according to claim 1,
After each of the first high-frequency power and the second high frequency power reaches a predetermined value of each plasma, characterized in that each pulse modulating said second high-frequency power from the first high-frequency power Processing method. In the plasma processing method of Claim 3,
The plasma processing method characterized by gel Tachinobo the output of the second high frequency power source so that the second high frequency power reaches a predetermined value in at least two stages. The plasma processing method according to claim 1,
The plasma processing method characterized in that to the first pulse rising to Jo Tokoro time delay relative to the rise of the second pulse. In the plasma processing method of Claim 5,
The plasma processing method characterized in that to the second pulse falling Jo Tokoro time delay relative to the falling edge of the first pulse. In the plasma processing method of Claim 5,
Plasma processing method for causing slow cast the rise of the output of said first high-frequency power to the rise of the output of the second high frequency power supply. In the plasma processing method of Claim 7,
Plasma processing method for causing the first slow the fall of the output of said second high-frequency power to the fall of the output of the high frequency power supply cast. Supply and the vacuum vessel flop plasma is generated, the first and the high frequency power source for supplying a first high-frequency power for generating the plasma, a second high-frequency power to the sample stage to the object to be processed is Ru placed in the plasma processing method for processing flop plasma using a plasma processing apparatus and a second high frequency power supply which,
Let n be a natural number, if the first frequency of pulses for pulse modulating said first radio frequency power of said second high-frequency power to the second frequency of pulses for pulse modulation is n times ,
The duty ratio and the duty ratio of the second pulse of the first pulse, n-1 + (duty ratio before Symbol first pulse) <n × a (duty ratio before Symbol second pulse) A plasma processing method characterized by satisfying the relationship . Supply and the vacuum vessel, first a high frequency power source for supplying a first high-frequency power for generating the plasma, a second high-frequency power to the sample stage to the object to be processed is placed the flop plasma is generated in the plasma processing method for processing flop plasma using a plasma processing apparatus and a second high frequency power supply which,
Having said first high-frequency power and the second high-frequency power process each synchronize the modulating time,
The output of the first high-frequency power to said are time-modulation, a second case where the output of the high-frequency power is turned on, the second high-frequency power which is modulated is off Rutotomoni the time the being time modulated The plasma processing method is characterized in that it is turned off when the output of is turned off. The plasma processing method according to claim 10,
The plasma processing method according to claim 1, wherein when the output of the second high frequency power supply is turned on , the output of the first high frequency power supply is turned on a plurality of times .

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