Three-stage pulsed system and method for plasma processing

Abstract

A plasma processing method includes performing a reactive species control phase, performing an ion / free radical control phase, and performing a byproduct control phase. The reactive species control phase includes applying source power to a processing chamber in a pulsed manner to generate ions and free radicals in a plasma. The ion / free radical control phase is performed after the reactive species control phase. The ion / free radical control phase includes reducing the source power to the processing chamber and applying bias power to a substrate in the processing chamber in a pulsed manner. The byproduct control phase is performed after the ion / free radical control phase. The byproduct control phase includes reducing the source power to the processing chamber relative to the reactive species control phase and reducing the bias power to the substrate relative to the ion / free radical control phase.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to the following non-provisional application: U.S. Patent Application Serial No. 16 / 540,160, filed August 14, 2019, entitled “THREE-PHASE PULSING SYSTEMS AND METHODS FOR PLASMA PROCESSING”, which is incorporated herein by reference in its entirety. Technical Field

[0003] The present invention generally relates to plasma processing, and in specific embodiments, to systems and methods for performing plasma processing using three-stage pulses. Background Technology

[0004] Device fabrication within microelectronic workpieces can involve a range of manufacturing techniques, including the formation, patterning, and removal of multiple material layers on a substrate. To achieve the physical and electrical specifications of current and next-generation semiconductor devices, it is desirable to reduce the fabrication process size while maintaining structural integrity for various patterning processes.

[0005] Plasma processes are commonly used to form devices in microelectronic workpieces. For example, plasma etching and plasma deposition are common process steps during semiconductor device fabrication. During plasma processing, a combination of source power and bias power can be used to generate and guide the plasma. Byproducts may be generated during the etching and deposition stages. The presence of byproducts can be either beneficial or detrimental, depending on the density of byproducts at the substrate and in the plasma system. Summary of the Invention

[0006] According to an embodiment of the present invention, a plasma processing method includes performing a reactive substance control phase, an ion / radical control phase, and a byproduct control phase. The reactive substance control phase includes applying source power to a processing chamber in a pulsed manner to generate ions and radicals in the plasma. The ion / radical control phase is performed after the reactive substance control phase. The ion / radical control phase includes reducing the source power to the processing chamber and applying a bias power to a substrate in the processing chamber in a pulsed manner. The byproduct control phase is performed after the ion / radical control phase. The byproduct control phase includes reducing the source power to the processing chamber relative to the reactive substance control phase and reducing the bias power to the substrate relative to the ion / radical control phase.

[0007] According to another embodiment, a plasma processing method includes cyclically processing a substrate using power pulses. During the cycle of power pulses, a source power pulse is applied to a coupling element and a bias power pulse is applied to a substrate holder supporting the substrate. The cycle of power pulses includes a first phase, a second phase, and a third phase. The first phase includes a first source power level and a first bias power level. The first bias power level is greater than zero. The second phase includes a second source power level and a second bias power level. The second source power level is less than the first source power level. The second bias power level is greater than the second source power level. The third phase includes a third source power level and a third bias power level. The third source power level is less than the first source power level. The third bias power level is less than the second bias power level.

[0008] According to another embodiment of the present invention, a plasma processing method includes applying a source power pulse to a plasma processing chamber during a first stage. The first stage includes a first source power level greater than zero. The first stage further includes a first bias power level. The method further includes applying a bias power pulse to a substrate in the plasma processing chamber during a second stage following the first stage. The second stage includes a second source power level less than the first source power level and a second bias power level greater than the second source power level. The method further includes reducing the amount of byproducts in the plasma processing chamber during a third stage following the second stage. The third stage includes a third source power level less than the first source power level and a third bias power level less than the second bias power level. Attached Figure Description

[0009] To gain a more complete understanding of the invention and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, in which:

[0010] Figure 1 A schematic timing diagram and corresponding qualitative curve diagram of an example plasma processing method according to an embodiment of the present invention are shown;

[0011] Figure 2 A schematic timing diagram of another example plasma processing method according to an embodiment of the present invention is shown;

[0012] Figure 3 A schematic timing diagram of yet another example plasma processing method according to an embodiment of the present invention is shown;

[0013] Figure 4 A schematic timing diagram of yet another example plasma processing method according to an embodiment of the present invention is shown;

[0014] Figure 5 A block diagram of an example plasma processing system according to an embodiment of the present invention is shown;

[0015] Figure 6A , Figure 6B and Figure 6C A schematic diagram of an inductively coupled plasma processing apparatus according to an embodiment of the present invention is shown, wherein, Figure 6A An inductively coupled plasma processing apparatus was demonstrated during the reactive matter control phase. Figure 6B An inductively coupled plasma processing apparatus was demonstrated during the ion / radical control phase, and Figure 6C An inductively coupled plasma processing apparatus was demonstrated during the byproduct control phase.

[0016] Figure 7 An example plasma processing method according to an embodiment of the present invention is shown; and

[0017] Figure 8 Another example plasma processing method according to an embodiment of the present invention is shown.

[0018] Unless otherwise indicated, corresponding numbers and symbols in different figures generally refer to corresponding parts. Figures are drawn to clearly illustrate relevant aspects of the embodiments, and these figures are not necessarily drawn to scale. The edges of features drawn in the figures do not necessarily indicate the termination of a feature range. Detailed Implementation

[0019] The following sections discuss in detail the making and use of various embodiments. However, it should be understood that the various embodiments described herein can be applied to a wide variety of specific situations. The specific embodiments discussed are merely illustrative of specific ways of making and using the various embodiments and should not be interpreted in a limited manner.

[0020] When implementing plasma processing techniques (e.g., pulsed processing), controlling the plasma processing characteristics can be critical. For example, the generation of reactive substances, the ion-to-radical ratio, ion energy (and ion angle), byproducts, and the ratio of ions and radicals to byproducts can affect the precision and feature accuracy during a given plasma process. Therefore, it is desirable to be able to independently control various plasma processing characteristics. For instance, enhanced control over reactive substances, radicals, and byproducts can facilitate the formation of contacts, fins, gate lines, other front-end or back-end processes, and general patterning steps, as well as other plasma processes.

[0021] Source power can be applied to coupling elements (e.g., coils of a helical resonator) to generate high-density plasma. Bias power can be applied to a substrate holder to couple energy to ions at the substrate supported by the substrate holder. The coupling elements generate both reactive substances and radicals in the plasma. As an example, ion energy and ion angle can affect the quality, uniformity, selectivity, and predictability of plasma processes. Advanced pulsed techniques (APT), which adjust the application of source and bias power during plasma processes, can be particularly useful for controlling ion energy, ion angle (i.e., the incident angle of ions at the substrate surface), and ion flux at the substrate. Because source power controls the current flowing to the substrate, and bias power controls the voltage between the plasma and the substrate, a combination of source and bias power can be used to control energy and angle.

[0022] Because byproducts can be a controlling factor in profile (e.g., the angle formed by the sidewalls and the substrate), managing byproducts can be important. The formation, density, and removal of byproducts can affect profile control (e.g., sidewall verticality), precision, cleanliness, the rate and type of reactions occurring on the substrate, and more. The presence of byproducts can be the result of many factors. For example, byproducts may form on the substrate but may also be altered by the plasma. Pressure can affect the release of byproducts from the substrate and the redeposition of byproducts on the substrate. Byproducts may form within the feature and be deposited directly on the sidewalls. Furthermore, byproducts can affect the deposition profile (e.g., the verticality of the feature sidewalls) and plasma uniformity.

[0023] When the quantity and density of byproducts in a plasma processing system are not specifically controlled, achieving the desired plasma processing results may be difficult. In particular, byproducts can cause problems due to passive involvement during plasma processing. For example, during etching processes, after byproducts are released into the region near the substrate, they may be altered by the plasma. Subsequently, the byproducts can be redeposited onto the substrate and / or removed by the gas flow. It may be desirable to maintain the density or flux of byproducts at the substrate within a certain range to achieve the desired plasma processing results.

[0024] The various embodiments described herein advantageously divide control into three independent operational phases: reactive substance control, ion / radical control, and byproduct control. During each control phase, a set of process parameters can be controlled to primarily or completely influence a specific set of plasma processing characteristics. In this way, the potential benefits of true functional separation in plasma processing can be realized. The separate management of the three sets of process parameters advantageously enables high-precision topology control during plasma processing.

[0025] During the reactive substance control phase, the generation of reactive substances can be controlled. In the ion / radical control phase, various plasma processing characteristics related to ions and radicals can be controlled, such as the ion-to-radical ratio, ion energy, ion angle, and ion flux at the substrate. During the byproduct control phase, plasma processing characteristics related to byproducts can be controlled, such as the amount of byproducts and the byproduct-to-ion / radical ratio. For example, byproducts can be removed from the system during the byproduct control phase.

[0026] Furthermore, during plasma processing, each control phase can be implemented during multiple repetitive cycles. A repetitive process with multiple control phases can advantageously provide greater variation in process parameters (e.g., ion / radical ratio, energy, etc.) than that achievable during continuous, non-repetitive processes. Moreover, continuous control of plasma processing characteristics in each cycle can advantageously reduce or eliminate the need for complex self-limiting processes that impair productivity (e.g., yield). For example, both atomic layer etching (ALE) and atomic layer deposition (ALD) techniques modify individual monolayers of a substrate using self-limiting chemicals to etch only the chemically modified surface monolayers. During conventional ALE processes, a single monolayer may be removed every 50 to 100 ms due to the self-limiting process. Yield can also be affected by gas switching and / or purging requirements. The benefits of the various embodiments described herein can be achieving high etching and deposition accuracy and high yield by eliminating or reducing self-limiting processes.

[0027] Furthermore, in conventional plasma processing techniques, etching byproducts can easily accumulate over time during substrate etching. Various embodiments described herein can include a byproduct removal stage in each cycle, thereby advantageously reducing or eliminating the accumulation of undesirable byproducts between cycles (e.g., on timescales longer than residence time). For a given plasma process, a set of process parameters can be tuned to appropriate values ​​corresponding to each control stage. These process parameters can include source pulse parameters (e.g., source power), bias pulse parameters (e.g., bias power), and stage duration, etc. Additional process parameters, such as delay between adjacent stages, gas flow rate, pulse shape, pulse frequency, number of pulses, gas composition, bias polarity, etc., can also be included.

[0028] The embodiments provided below describe various systems and methods for plasma processing, and specifically systems and methods for plasma processing using three-stage pulses. The following description describes embodiments. (Usage) Figure 1 An example schematic timing diagram of the plasma processing method of the embodiment is described. Using Figures 2 to 4Several other example schematic timing diagrams of the plasma processing method described in the embodiments are illustrated. Using Figure 5 An example block diagram of an embodiment of a plasma processing system is described. (Using...) Figure 6A and Figure 6B Two example schematic diagrams of an inductively coupled plasma processing apparatus are described. Using Figure 7 and Figure 8 Two embodiments of plasma processing methods are described.

[0029] Figure 1 A schematic timing diagram and corresponding qualitative curve are shown for an example plasma processing method according to an embodiment of the present invention.

[0030] refer to Figure 1 The schematic timing diagram 100 includes a source power P applied in a pulsed manner during cycle 150 to generate reactive substances, high-energy ions, and byproducts. S and bias power P B The cycle comprises three phases: a first phase 110, a second phase 120, and a third phase 130. In various embodiments, cycle 150 is a sequential cycle (e.g., these phases are executed sequentially). Furthermore, in some embodiments, cycle 150 is repeated (i.e., cyclically). In various embodiments, cycle 150 is repeated many times (e.g., >>1). For example, cycle 150 may be a sequential cycle of power pulses, during which a source pulse is applied to a plasma processing apparatus (e.g., a coupling element) and a bias pulse is applied to a plasma processing apparatus (e.g., a substrate holder supporting a substrate). Consequently, these three phases may also be referred to as pulse phases.

[0031] Each of these three stages is defined by a set of process parameters that are adjusted accordingly during a given stage. This set of process parameters includes the source power level, the bias power level, and the stage duration. For a given stage, a given parameter in this set of process parameters can be substantially constant. For example, the first stage 110 is defined by a first source power level P. S1 First bias power level P B1 The duration t1 of the first stage is defined. Similarly, the second stage 120 and the third stage 130 are defined by the second source power level P. S2 Second bias power level P B2 The duration of the second stage t2 and the third source power level P S3 Third bias power level P B3 And the duration of the third phase is limited to t3.

[0032] The first stage, 110, can be considered the reactive substance control stage. For induction sources, wave heating sources, or resonant sources, the generation of reactive substances can be directly related to the source power P. S Proportional. Therefore, in various embodiments, the first source power level P S1 It is enabled during the reactive substance control phase. In one embodiment, during the reactive substance control phase, at the bias power P B It is off (i.e., the first bias power level P). B1 When the first source power level P is equal to zero or essentially zero, S1 Greater than zero. Because the source power P of the plasma system is greater than zero during the reactive substance control phase. S It is enabled, so the reactive substance control phase can be considered the source power phase.

[0033] In other embodiments, the source power P S and bias power P B It is on throughout the reactive substance control phase. For example, the bias power P can be maintained or applied in a pulsed manner during the reactive substance control phase. B The ion energy that influences growth during the deposition process and / or maintains cleanliness by removing deposited material generated along with electrons, ions, and free radicals.

[0034] As shown in qualitative curve 102, the electron density N during the first stage 110 is... e and free radical density N r It is high. For example, during the first phase 110, the free radical density N... r It initially increases and then remains at a high level. Electron density N e It increases rapidly at the beginning of the first stage 110 and continues to increase throughout the entire first stage 110. Ion density versus electron density N e Proportional. Electron temperature T e and ion energy ε i Peaks are observed at the beginning of stage 110 and then remain substantially constant for the remainder. Although fewer byproducts are produced compared to the reactive substances in stage 110, byproducts can still be generated during stage 110. As shown in the figure, the byproduct density N during stage 110... bp It can gradually increase in size.

[0035] The second stage, 120, can be considered the ion / radical controlled stage. During the ion / radical controlled stage, the source power P is higher than that of the reactive substance controlled stage. S Reduce. For example, the source power P can be turned off during the duration of the ion / radical control phase. SReducing or removing source power P during the ion / radical control phase. S This can reduce or eliminate the current flowing to the substrate. Furthermore, the applied bias power P... B This may increase the voltage. During the ion / radical control phase, the second bias power level P B2 Greater than the second source power level P S2 Similarly, the second source power level P S2 Less than the first source power level P S1 .

[0036] As shown in qualitative curve 102, the electron density N e Rapidly decreases, while the free radical density N r Maintain a relatively constant temperature (e.g., decrease at a much lower rate). The electron temperature T is lower than that of the first stage (110). e It also remained essentially constant during the second phase, 120. Meanwhile, the ion energy ε... i It rapidly increases to a substantially constant value. It is worth noting that byproducts may be generated during the second stage (120) due to etching processes or other plasma processes. As shown in the figure, the byproduct density N... bp It increases faster in the second stage 120 than in the first stage 110.

[0037] Several plasma processing characteristics may be affected during the second phase 120. For example, the electron flux Γ at the substrate. e and ion flux Γ i It may decrease, while the energy flux Γ at the substrate... 能量 It may increase. Furthermore, the free radical flux Γ r It can be relative to the ion flux Γ i Maintaining a constant or gradually changing ratio leads to an increase in the ratio of free radicals to ions at the substrate (e.g., Γ). r >>Γ i For example, during the stay time T res When the duration of the ion / radical control phase is longer than that of the second duration t2, the radical flux Γ r With ion flux Γ i The reduction may not be significant. In this scheme, the free radical flux Γ r It can be considered constant, while the ion flux Γ i It can be considered transient, resulting in a free radical flux Γ r With ion flux Γ i The ratio increases.

[0038] Phase 3, 130, can be considered the byproduct control phase. As previously mentioned, byproducts may be generated during Phase 2, 120, and the various concentrations of these byproducts at the substrate may be desirable or undesirable. For example, byproducts may be generated that can advantageously affect the plasma process within a concentration range at the substrate. However, in the absence of a byproduct control phase, byproducts may undesirably accumulate beyond the advantageous range. Byproducts can accumulate cycle-by-cycle over multiple residence times, which may amplify the potential negative impacts of byproducts on inconsistencies and recombination in the plasma process. For example, byproducts may alter plasma characteristics between cycles.

[0039] During the by-product control phase, the source power P S Compared to the first stage 110 (e.g., the reactive substance formation stage), the bias power P is reduced, and the bias power P is lower. B The power level is reduced compared to the second stage 120 (e.g., the ion / radical control stage). In one embodiment, the third source power level P S3 and the third bias power level P B3 It is reduced to zero or essentially zero. Alternatively, the third source power level P S3 Or the third bias power level P B3 It can be non-zero. When the source power P S and bias power P B When the process is off or at a low level, byproducts can be removed. For example, material generation and etching processes can be reduced or eliminated during the byproduct control phase, advantageously allowing byproducts to be pumped out at a rate faster than the rate at which they are generated.

[0040] Due to the density of byproducts N at the substrate and in the plasma system bp The byproduct flux Γ at the substrate is decreasing. bp It may also decrease. Therefore, the ratio of ions to byproducts and the ratio of free radicals to byproducts can also be controlled during the byproduct control phase. For example, as shown in qualitative curve 102, the byproduct density N in the system... bp With relative free radical density N r and electron density N e (with ion density N) i The rates of change (i.e., decrease) are much higher than those of both (proportional to each other). Therefore, during the byproduct control phase, both the ratio of ions to byproducts and the ratio of free radicals to byproducts may change.

[0041] Source power P S This can be alternating current (AC) power. In some embodiments, the source power P SIt is radio frequency (RF) power, and in various embodiments, it is very high frequency (VHF). In some embodiments, the source power P S Between approximately 60 MHz and approximately 200 MHz. In other embodiments, the source power P S Between approximately 25 MHz and approximately 60 MHz, and in one embodiment 27 MHz. Source power P S It can generate capacitively coupled plasma (CCP), inductively coupled plasma (ICP), surface wave plasma (SWP), etc. For example, the source power P S It can be coupled to a helical resonator antenna to generate plasma.

[0042] Similarly, the bias power P B It can be AC ​​power. Alternatively, it can be bias power P. B This can be, for example, pulsed direct current (DC) power. In some embodiments, the bias power P B It is RF power and in various embodiments is high frequency (HF), while in other embodiments it is intermediate frequency (MF). In some embodiments, the bias power P B The frequency is between approximately 200 kHz and approximately 600 kHz, and in one embodiment is 400 kHz. In other embodiments, the bias power P B Between approximately 600 kHz and approximately 13 MHz.

[0043] During each of the three phases, the source power P S and bias power P B They can be applied individually or as a series of power pulses. For example, a first source power level P can be applied during the first phase duration t1. S1 A single source pulse is applied. Alternatively, a series of source pulses can be applied during the first phase duration t1. Similarly, a second source power level P can be applied during the second phase duration t2. B2 Apply a single bias power pulse or a series of bias power pulses.

[0044] The gas can be supplied to the processing chamber of the plasma processing apparatus at a desired flow rate, which can be selected according to a given plasma process. During cycle 150 (i.e., first stage 110, second stage 120, and third stage 130), the flow rate of the given plasma process can be maintained at a substantially constant value. In one embodiment, the gas comprises hydrogen bromide (HBr). In various embodiments, the gas comprises an inert gas, such as helium (He) or argon (Ar). The gas may also include oxygen (O2), carbon tetrafluoride (CF4), nitrogen trifluoride (NF3), sulfur hexafluoride (SF6), chlorine (Cl2), carbon tetrachloride (CCl4), etc.

[0045] Byproducts generated during the three stages (e.g., primarily in the second stage 120) can be compounds comprising elements from one or more substances in the gas from the processing chamber and / or elements from the substrate. For example, in the case where the substrate contains silicon (Si) and HBr gas, compounds containing silicon bromide (SiBr) may be formed. x Silicon is a byproduct of fluorine-silicon compounds. Additionally or alternatively, other byproducts may form, such as silicon-containing residues, like silicon-fluorine compounds (SiF). x ) and silicon chloride compounds (SiCl x ) etc.; carbon-containing residues (e.g., from photoresist, organic layers, or gaseous precursors), such as fluorocarbons (CFCs). x ), hydrofluorocarbons (CH4) x F y )wait.

[0046] Figure 2 A schematic timing diagram of another example plasma processing method according to an embodiment of the present invention is shown. For example, Figure 2 The schematic timing diagram can be a specific implementation of other schematic timing diagrams described herein, such as... Figure 1 A schematic timing diagram 100. Components with similar markings can be as previously described.

[0047] refer to Figure 2 The schematic timing diagram 200 includes a source power P applied in a pulsed manner during cycle 250 to generate reactive substances, ions, and byproducts. S and bias power P B The cycle consists of three phases: Phase 1 210, Phase 2 220, and Phase 3 230. Phase 1 210, Phase 2 220, Phase 3 230, and Cycle 250 can be respectively... Figure 1 Specific implementations of the first stage 110, the second stage 120, the third stage 130, and the cycle 150. For example, a schematic timing diagram 200 is applied in which the bias power P is... B In the first stage 210 and the third stage 230, it is (basically) off and the source power P S In Phase 3, 230, there is a specific example of a shutdown.

[0048] As shown in the figure, cycle 250 is a sequential cycle of power pulses that is repeatedly (e.g., cyclically) executed during the plasma process. This cycle includes a reactive substance control phase (first stage 210), an ion / radical control phase (second stage 220), and a byproduct control phase (third stage 230). During the first stage 210, the first source power level P... S1 Greater than zero (i.e., source power P)S (It is enabled) and the first bias power level P B1 The bias power P is zero or essentially zero (i.e., the bias power P) B (It is off). In various embodiments, the first source power level P S1 The power during the first phase 210 is between approximately 700 W and approximately 900 W, and in one embodiment, it is approximately 800 W during the first phase 210. In various embodiments, the duration t1 of the first phase is between approximately 10 μs and approximately 100 μs. In one embodiment, the duration t1 of the first phase is approximately 20 μs.

[0049] During the second phase 220, the second bias power level P B2 Greater than the second source power level P S2 Optionally, during the second phase 220, the source power P S It is turned off (i.e., the second source power level P) S2 (Number is zero or substantially zero). In various embodiments, the second bias power level P B2 The second stage 220 is between approximately 300 W and approximately 500 W, and in one embodiment, it is approximately 400 W. In various embodiments, the duration t2 of the second stage is between approximately 20 μs and approximately 100 μs. In one embodiment, the duration t2 of the second stage is approximately 70 μs.

[0050] During phase 3, 230, the source power P S It is off (i.e., the third source power level P). S3 (zero or essentially zero) and bias power P B It is off (i.e., the third bias power level P). B3 (The duration of the third stage, t3, can be on the order of the local residence time of the gas at the substrate surface. In contrast, the residence time of byproducts at the substrate surface can be much shorter (e.g., due to high flow rates). Therefore, when the duration of the third stage, t3, is less than the local residence time of the gas, byproducts can be advantageously removed at the substrate surface at a faster rate than free radicals. In various embodiments, the duration of the third stage, t3, is between about 50 μs and about 3 ms. In one embodiment, the duration of the third stage, t3, is about 100 μs. In another embodiment, the duration of the third stage, t3, is about 1 ms.

[0051] Figure 3 A schematic timing diagram of yet another example plasma processing method according to an embodiment of the present invention is shown.

[0052] refer to Figure 3The schematic timing diagram 300 includes a source power P applied in a pulsed manner during cycle 350 to generate reactive substances, ions, and byproducts. S and bias power P B The cycle consists of three phases: Phase 1 310, Phase 2 320, and Phase 330. Phase 1 310, Phase 2 320, Phase 330, and Cycle 350 can be respectively... Figure 1 Specific implementations of the first stage 110, the second stage 120, the third stage 130, and the cycle 150. For example, a schematic timing diagram 300 is applied to the source power P. S and bias power P B This is a specific example of what is enabled in Phase 1, 310.

[0053] As shown in the figure, cycle 350 is a sequential cycle of power pulses that is repeatedly (e.g., cyclically) executed during the plasma process. This cycle includes a reactive substance control phase (first stage 310), an ion / radical control phase (second stage 320), and a byproduct control phase (third stage 330). During the first stage 310, the first source power level P... S1 Greater than zero (i.e., source power P) S (It is enabled) and the first bias power level P B1 It is also greater than zero (i.e., the bias power P). B (It is enabled). As shown in the figure, the first bias power level P B1 It can be higher than the first source power level P S1 Alternatively, the first bias power level P B1 It can also be equal to or less than the first source power level P. S1 .

[0054] In various embodiments, the first source power level P S1 During the first phase 310, the power level is between approximately 100W and approximately 200W, and in one embodiment, it is approximately 150W during the first phase 310. In various embodiments, the first bias power level P B1 The power during the first phase 310 is between approximately 400 W and approximately 600 W, and in one embodiment, it is approximately 500 W during the first phase 310. In various embodiments, the duration t1 of the first phase is between approximately 10 μs and approximately 100 μs. In one embodiment, the duration t1 of the first phase is approximately 20 μs.

[0055] During the second phase 320, the second bias power level P B2 Greater than the second source power level P S2 Second source power level P S2 Below the first source power level P S1Optionally, during the second phase 320, the source power P S It is turned off (i.e., the second source power level P) S2 (Zero or substantially zero). As shown in the figure, in some embodiments, the second bias power level P B2 It can be (basically) equal to the first bias power level P B1 Alternatively, the second bias power level P B2 It can also be greater than or less than the first bias power level P B1 .

[0056] In various embodiments, the second source power level P S2 During the second phase 320, the power level is between 0W and approximately 100W. In one embodiment, the second source power level P... S2 During the second phase 320, it is approximately 50W. In another embodiment, the second source power level P S2 During the second phase 320, it is 0W. In various embodiments, the second bias power level P... B2 The second stage 320 is between approximately 400 W and approximately 600 W, and in one embodiment, it is approximately 500 W. In various embodiments, the duration t2 of the second stage is between approximately 20 μs and approximately 100 μs. In one embodiment, the duration t2 of the second stage is approximately 70 μs.

[0057] During phase 330, the source power P S It is low (i.e., the third source power level P). S3 Less than the first source power level P S1 And the bias power P B It is also low (i.e., the third bias power level P). B3 Less than the second bias power level P B2 The duration t3 of the third stage can be on the order of the local residence time of the gas at the surface of the substrate (e.g., longer than the duration t1 of the first stage and longer than the duration t2 of the second stage, as shown in the figure).

[0058] Figure 4 A schematic timing diagram of yet another example plasma processing method according to an embodiment of the present invention is shown.

[0059] refer to Figure 4 The schematic timing diagram 400 includes a source power P applied in a pulsed manner during cycle 450 to generate reactive substances, ions, and byproducts. S and bias power P BThe cycle consists of three phases: Phase 1 410, Phase 2 420, and Phase 3 430. Phase 1 410, Phase 2 420, Phase 3 430, and Cycle 450 can be respectively... Figure 1 Specific implementations of the first stage 110, the second stage 120, the third stage 130, and the loop 150. A schematic timing diagram 400 is applied to each of the three stages, further defined by additional parameters representing the delay D between adjacent stages, as in a specific example.

[0060] As shown in the figure, cycle 450 is a sequential cycle of power pulses that is repeatedly (e.g., cyclically) executed during the plasma process. This cycle includes a reactive substance control phase (first stage 410), an ion / radical control phase (second stage 420), and a byproduct control phase (third stage 430). As previously described, the first stage 410 is characterized by the inequality P S1 >0, the second stage 420 is characterized by inequality P B2 >P S2 and P S2 <P S1 Furthermore, the third stage 430 is characterized by the inequality P. S3 <P S1 and P B3 <P B2 However, it also includes an additional parameter representing the delay D between adjacent stages. During the delay period, the source power P S and bias power P B Both can be turned off or essentially turned off.

[0061] Specifically, in this example, the first stage 410, the second stage 420, and the third stage 430 are respectively determined by the parameter group {P} S1 ,P B1 ,t1,D1}、{P S2 ,P B2 ,t2,D2} and {P S3 ,P B3 The interval is defined as follows: ,t3,D3}, where D1 is the first delay between the first stage 410 and the second stage 420, D2 is the second delay between the second stage 420 and the third stage 430, and D3 is the delay between the third stage 430 and the subsequent first stage 410 of the new cycle 450 as the cycle 450 is executed cyclically. Additionally or alternatively, the delay D between stages may also be negative, resulting in overlap between stages.

[0062] The delay parameter can be included in any of the embodiments described herein. For example, in various embodiments, the first delay D1 can be between about 5 μs and about 15 μs, and in one embodiment it is about 10 μs. This value of the first delay D1 can be combined with reference to... Figure 2 The described example is used for reference. In this particular example, the first delay D1 is shorter than both the first stage duration t1 and the second stage duration t2, but this is not always necessary. In other embodiments, the first delay D1 can be between about 500 μs and about 3 ms, and in one embodiment it is about 1 ms. This value of the first delay D1 can be combined with reference to... Figure 3 The examples described are used for this purpose. Here, the first delay D1 is longer than the first stage duration t1 and the second stage duration t2. The second delay D2 and the third delay D3 can be varied in a similar manner depending on the desired characteristics of a given plasma process.

[0063] Figure 2 The schematic timing diagram 200 can represent an embodiment of a specific group of plasma processing methods. For example, the schematic timing diagram 200 can be used during a silicon etching plasma process. The gas supplied during this process may include, for example, inert gases such as He or Ar, HBr, and small amounts of O2 and / or CF4. First source power level P S1 It can be approximately 800W, with the first bias power level P. B1 It can be zero or substantially zero, the first stage duration t1 can be approximately 20 μs, and the first delay D1 can be approximately 10 μs. Optionally, the first bias power level P B1 It can provide approximately 500W to keep the feature wall at the bottom surface clean. Second source power level P S2 The second bias power level P can be zero or essentially zero. B2 It can be approximately 400W, and the second stage duration t2 can be approximately 70μs. Optionally, the second source power level P S2 It can be approximately 100W to increase the flux during the second stage. The third source power level P S3 and the third bias power level P B3 The duration t3 of the third stage can be zero or essentially zero, while the value of t3 can range from hundreds of microseconds (e.g., 100 μs) to several milliseconds (e.g., 3 ms).

[0064] Similarly, schematic timing diagram 300 can represent different groups of plasma processing embodiments. For example, schematic timing diagram 300 can be used during a silicon nitride etching process. For example, this etching process can be similar to atomic layer etching (ALE). The gas supplied during this process can include, for example, an inert gas such as Ar and a small amount (e.g., 5%) of fluorinated carbon (e.g., C4F6 or C4F8). First source power level P S1 The first bias power level P can be between approximately 100W and approximately 200W. B1 It can be approximately 500W, and the first delay D1 can be on the order of the bipolar diffusion time of the plasma. The bipolar diffusion time can be longer than the first stage duration t1 and the second stage duration t2. As mentioned above, the first bias power level P B1 Approximately 500W can be used to keep the feature walls at the bottom surface clean, which can be important when fluorine is involved. For example, bias power may be needed in the first stage to control polymerization at the substrate. The second source power level P S2 It can be zero or essentially zero, and the second bias power level P B2 It can be approximately 500W. Second bias power level P B2 It can be higher than that in silicon etching plasma processes. Optionally, the second source power level P S2 The flux during the second stage can be increased to between 0W and approximately 100W. The third source power level P... S3 and the third bias power level P B3 The duration t3 of the third stage can be zero or essentially zero, while the value of t3 can range from hundreds of microseconds (e.g., 100 μs) to several milliseconds (e.g., 3 ms).

[0065] Figure 5 A block diagram of an example plasma processing system according to an embodiment of the present invention is shown. Figure 5 The plasma processing system can be used to implement, for example, schematic timing diagrams of any of the embodiment methods described herein, such as... Figure 1 A schematic timing diagram. Furthermore, Figure 5 The plasma processing system can be used, for example, to perform any of the embodiments of the methods described herein, such as... Figure 7 and Figure 8 The method.

[0066] refer to Figure 5 The plasma processing system 500 includes a source power coupling element 511 coupled to a processing chamber 540. The source power coupling element 511 can be disposed in or adjacent to the processing chamber 540. The source power coupling element 511 allows the source power P to be coupled to the processing chamber 540. SAn application is made to the processing chamber 540, resulting in the generation of plasma 60. In various embodiments, the source power coupling element 511 is a conductive coil positioned around the processing chamber 540, and in one embodiment is a quarter-wave helical resonator. In another embodiment, the source power coupling element 511 is a half-wave helical resonator, which can be implemented as a planar helical coil positioned above the processing chamber 540. Alternatively, as examples, other source power coupling elements such as antennas, electrodes, waveguides, or electron beams can be used.

[0067] The plasma processing system 500 further includes a bias power coupling element 521 coupled to the processing chamber 540. The bias power coupling element 521 can realize the bias power P B The bias power coupling element 521 is applied to the microelectronic workpiece being processed. In various embodiments, the bias power coupling element 521 is a substrate holder and, in one embodiment, an electrostatic chuck. The bias power coupling element 521 may also refer to a substrate holder supporting the substrate or simply the substrate itself.

[0068] The source power P can be controlled using the source power control path 17, which includes the source power pulse modulation circuit 51. S Coupled to the processing chamber 540. The source power pulse modulation circuit 51 can modulate the source signal between a high-amplitude state and a low-amplitude state. The modulated source signal can be received by a function generator 15, which can superimpose a waveform onto the modulated source signal. The function generator 15 may also optionally include an amplifier circuit configured to increase the amplitude of the modulated source signal.

[0069] The frequency of the superimposed waveform can be higher than the pulse modulation frequency. In various embodiments, the frequency of the superimposed waveform can be an RF frequency, and in one embodiment, approximately 13.56 MHz. Therefore, each of the resulting source power pulses can include several cycles of the superimposed waveform. The waveform shape can include periodic waveforms such as sine waves, square waves, sawtooth waves, etc. Alternatively, the waveform shape can include non-periodic waves, such as the superposition of multiple sine waves of various frequencies to generate arbitrary waveform shapes.

[0070] The source power control path 17 may include an optional source impedance matching network 13. The source power pulse generated by the function generator 15 can pass through the optional source impedance matching network 13 before being coupled to the processing chamber 540 via the source power coupling element 511. In some plasma processing systems, such as when the source power coupling element 511 is inductively coupled to a resonant structure of the plasma 60, the optional source impedance matching network 13 may be omitted. Conversely, when the source power coupling element 511 is non-resonant, the optional source impedance matching network 13 may be included. The optional source impedance matching network 13 can be used to ensure the source power P by matching the impedance of the load to the impedance of the power supply.S It is efficiently coupled to the plasma 60.

[0071] Still referencing Figure 5 Bias power P B The bias power control path 27 can be coupled to the machining chamber 540. The bias power control path 27 can be coupled to the source power control path 17 via a pulse modulation timing circuit 52. The pulse modulation timing circuit 52 can determine the timing of the bias power pulse relative to the timing of the source power pulse generated by the source power control path 17. The pulse modulation timing circuit 52 can receive a signal from the source power pulse modulation circuit 51 and introduce a delay triggered by the leading or trailing edge of the source power pulse. Alternatively, the pulse modulation timing circuit 52 can determine the timing of the source power pulse relative to the timing of the bias power pulse generated by the bias power control path 27.

[0072] Similar to source power control path 17, bias power control path 27 may include an optional bias power pulse modulation circuit 53 triggered by pulse modulation timing circuit 52. The optional bias power pulse modulation circuit 53 can modulate the bias signal between high-amplitude and low-amplitude states. Alternatively, the optional bias power pulse modulation circuit 53 may be omitted, and a delayed modulated source signal may correspond to the bias power pulse.

[0073] The modulated bias signal can be received by an optional function generator 25. The optional function generator 25 can superimpose a waveform onto the modulated bias signal. This waveform can be similar to or different from the waveform superimposed on the modulated source signal and can have any desired waveform shape as previously described. The optional function generator 25 may also optionally include amplifier circuitry for increasing the amplitude of the modulated bias signal. In one embodiment, the bias power P transmitted to the processing chamber 540... B The bias power delivered to the processing chamber 540 is AC power. Alternatively, the bias power delivered to the processing chamber 540 is DC power. In this case, the optional function generator 25 can be omitted. In some cases where amplification is required but function generation is not, the optional function generator 25 can be replaced by an amplifier circuit.

[0074] A bias power impedance matching network 23 is also included in the bias power control path 27 between the optional function generator 25 and the bias power coupling element 521. The bias power impedance matching network 23 can be used to ensure bias power P by matching the impedance of the load to the impedance of the power supply. B It is efficiently coupled to the processing chamber 540.

[0075] One or more of the components described above may be included in the controller. For example, such as Figure 5As shown, the source power pulse modulation circuit 51, the pulse modulation timing circuit 52, and the optional bias power pulse modulation circuit 53 may be included in the controller 50. The controller 50 may be locally located relative to the machining chamber 540. Alternatively, the controller 50 may be remotely located relative to the machining chamber 540. The controller 50 may be able to exchange data with one or more of the elements included in the source power control path 17 and the bias power control path 27. Each of the impedance matching networks may be controlled by the controller 50 or may include a separate controller.

[0076] The controller 50 can be configured to set, monitor, and / or control various process parameters associated with generating plasma and fabricating microelectronic workpieces using the three-stage cycle described herein. Process parameters may include, but are not limited to, power levels of both source power and bias power, frequency and duty cycle percentage, stage duration, delay between adjacent stages, gas flow rate, pulse shape, pulse frequency, number of pulses, gas composition, bias polarity, etc. Other process parameters may also be used.

[0077] Figure 6A , Figure 6B and Figure 6C A schematic diagram of an inductively coupled plasma processing apparatus according to an embodiment of the present invention is shown, wherein, Figure 6A An inductively coupled plasma processing apparatus was demonstrated during the reactive matter control phase. Figure 6B An inductively coupled plasma processing apparatus was demonstrated during the ion / radical control phase, and Figure 6C An inductively coupled plasma processing apparatus was demonstrated during the byproduct control phase.

[0078] refer to Figure 6A , Figure 6B and Figure 6C The inductively coupled plasma (ICP) processing system 600 includes an AC power source 67, which may include generator circuitry. The AC power source 67 is coupled to an inductor 611 disposed adjacent to the processing chamber 640. In one embodiment, the inductor 611 is a planar coil as shown. In other embodiments, the inductor 611 is a helical resonator coil. For example, the inductor 611 may be… Figure 5 A specific embodiment of the source power coupling element 511. It may also include a bias power supply 65 of the generator circuit coupled to a substrate holder 621 that can support the substrate 16. For example, the substrate holder 621 may be... Figure 5 Specific implementation of the bias power coupling element 521.

[0079] The processing chamber 640 also includes one or more pump outlets 70. The gas flow rate through the pump outlets 70 can advantageously facilitate the removal of byproducts from the processing chamber 640. In various embodiments, the pump outlets 70 are positioned near (e.g., below or around) the substrate holder 621 and the substrate 16.

[0080] The AC power supply 67 and the bias power supply 65 can be configured according to, for example... Figures 1 to 5 The previously described embodiments generate source power P respectively. S and bias power P B Plasma 60 is formed close to substrate 16 between inductor 611 (e.g., planar or solenoid / spiral coil or antenna) and substrate holder 621. Dielectric material (not shown) can separate inductor 611 from plasma 60.

[0081] Now for reference Figure 6A Plasma 60 can be generated during the reactive material control phase of plasma processes. Plasma 60 can serve as a source for various substances, such as ion sources like S. i Electronic source S e and free radical source S r These sources can generate corresponding fluxes (ion flux Γ) that disperse from plasma 60 in all directions. i Electron flux Γ e and free radical flux Γ r During the reactive material control phase, a byproduct flux Γ from substrate 16 may also be generated. bp The byproducts represented, such as energy flux Γ. 能量 As depicted, energy can also be transferred to substrate 16 during the reactive material control phase.

[0082] Now for reference Figure 6B Although the electron flux Γ at substrate 16 e and ion flux Γ i It can reduce the energy flux Γ at the same time 能量 The flow rate can be increased, but plasma 60 (although not shown) can still exist in the ion / radical control phase (e.g., as afterglow). The flow rate Q can transport material toward the sidewalls of the processing chamber 640. During the ion / radical control phase, the radical flux Γ... r It can remain substantially constant, as indicated by the arrow pointing towards substrate 16. During the ion / radical control phase, the substantially constant radical flux Γ r Combined with reduced ion flux Γ i This may reduce the ratio of ions to free radicals.

[0083] Now for reference Figure 6CDue to the very low or zero source power, plasma 60 may or may not be present in the byproduct control phase, as shown in the figure. During the byproduct control phase, the flow rate Q continues toward the side of the processing chamber 640 and the gas flow 31 can transport the byproducts to the pump outlet 70 at a rate faster than the formation of new byproducts. This can reduce the byproduct flux Γ at the substrate 16. bp Furthermore, a byproduct flow rate BP is introduced and / or increased, which delivers the byproduct to the side of the processing chamber 640 and the pump outlet 70. For example, in the ion / radical control phase, the radical flux Γ... r It can continue to remain essentially constant (e.g., decreasing very slowly relative to the duration of the byproduct control phase).

[0084] Figure 7 An example plasma processing method according to an embodiment of the present invention is illustrated. It can be performed using the schematic timing diagrams and embodiment plasma processing systems and apparatus as described herein. Figure 7 The method. For example, Figure 7 The method can be with Figure 1 Any combination of the embodiments shown in Figure 6. It should be noted that although the arrows are intended to show a specific sequence of events, as... Figure 7 The method illustrated is not intended to be limited to a particular order. Therefore, the method steps described below can be performed in any suitable order as will be apparent to those skilled in the art.

[0085] Step 710 of plasma processing method 700 includes applying a source power pulse to the plasma processing chamber during a first stage defined by the following first set of process parameters: {P S1 ,P B1 ,t1}, where P S1 >0. Step 720 includes applying a bias power pulse to the substrate in the plasma processing chamber during a second stage defined by the following second set of process parameters: {P S2 ,P B2 ,t2}, where P S2 <P S1 And P B2 >P S2 Step 730 includes reducing the amount of byproducts in the plasma processing chamber during the third stage, defined by the following third set of process parameters: {P S3 ,P B3 ,t3}, where P S3 <P S1 And P B3 <P B2As shown in the figure, the combination of steps 710, 720, and 730 is loop 750. Step 710 can be repeated after step 730, as indicated by the dashed arrow.

[0086] Figure 8 Another example plasma processing method according to an embodiment of the present invention is illustrated. It can be performed using the schematic timing diagrams and embodiment plasma processing systems and apparatus as described herein. Figure 8 The method. For example, Figure 8 The method can be with Figure 1 Any combination of the embodiments shown in Figure 6. It should be noted that although the arrows are intended to show a specific sequence of events, as... Figure 8 The method illustrated is not intended to be limited to a particular order. Therefore, the method steps described below can be performed in any suitable order as will be apparent to those skilled in the art.

[0087] Step 810 of the plasma processing method 800 includes applying source power to the processing chamber in a pulsed manner to generate ions and free radicals in the plasma. Step 820 includes reducing the source power to the processing chamber and applying bias power to the substrate of the processing chamber in a pulsed manner. Step 830 includes reducing the source power to the processing chamber and reducing the bias power to the substrate. As shown, the combination of steps 810, 820, and 830 is cycle 850. Step 810 can be repeated after step 830, as indicated by the dashed arrow.

[0088] Exemplary embodiments of the invention are summarized herein. Other embodiments may also be understood from the entire specification and the claims set forth herein.

[0089] Example 1. A plasma processing method comprising: performing a reactive substance control phase, the reactive substance control phase including applying source power to a processing chamber in a pulsed manner to generate ions and radicals in a plasma; performing an ion / radical control phase after the reactive substance control phase, the ion / radical control phase including reducing the source power to the processing chamber and applying a bias power to a substrate in the processing chamber in a pulsed manner; and performing a byproduct control phase after the ion / radical control phase, the byproduct control phase including reducing the source power to the processing chamber relative to the reactive substance control phase and reducing the bias power to the substrate relative to the ion / radical control phase.

[0090] Example 2. The method as described in Example 1 further includes: cyclically performing the reactive substance control phase, the ion / radical control phase, and the byproduct control phase.

[0091] Example 3. The method as described in any one of Examples 1 and 2 further includes: supplying a gas to the processing chamber, wherein the flow rate of the gas is substantially constant during the reactive substance control phase, the ion / radical control phase, and the byproduct control phase.

[0092] Example 4. The method as described in any one of Examples 1 to 3, wherein the reactive material control phase further includes applying the bias power to the substrate in a pulsed manner.

[0093] Example 5. The method as described in any one of Examples 1 to 4, wherein the byproduct control phase further comprises: reducing the source power to substantially zero for the entire byproduct control phase; and reducing the bias power to substantially zero for the entire byproduct control phase.

[0094] Example 6. The method as described in any one of Examples 1 to 5, wherein the byproduct control stage further comprises: applying the bias power to the substrate in a pulsed manner to control the redeposition of byproducts on the substrate.

[0095] Example 7. An apparatus configured to perform the method as described in any one of Examples 1 to 6, the apparatus comprising: a coupling element disposed adjacent to the processing chamber; a substrate holder supporting the substrate; a source power supply node coupled to the coupling element and configured to apply the source power in a pulsed manner; and a bias power supply node coupled to the substrate holder and configured to apply the bias power in a pulsed manner.

[0096] Example 8. A plasma processing method comprising: processing a substrate using a cycle of power pulses, wherein during the cycle of the power pulses, a source power pulse is applied to a coupling element and a bias power pulse is applied to a substrate holder supporting the substrate; wherein the cycle of the power pulses includes a first phase including a first source power level and a first bias power level; a second phase including a second source power level and a second bias power level; and a third phase including a third source power level and a third bias power level; wherein the first bias power level is greater than zero; wherein the second source power level is less than the first source power level; wherein the second bias power level is greater than the second source power level; wherein the third source power level is less than the first source power level; and wherein the third bias power level is less than the second bias power level.

[0097] Example 9. The method described in Example 8 further includes repeatedly performing a cycle of the power pulse.

[0098] Example 10. The method as described in one of Examples 8 and 9, wherein the first bias power level is substantially zero.

[0099] Example 11. The method as described in any one of Examples 8 to 10, wherein the first bias power level is greater than zero.

[0100] Example 12. The method as described in any one of Examples 8 to 11, wherein the third bias power level is greater than zero.

[0101] Example 13. The method as described in any one of Examples 8 to 12, wherein both the third source power level and the third bias power level are substantially zero.

[0102] Example 14. An apparatus configured to perform the method as described in any one of Examples 8 to 13, the apparatus comprising: a processing chamber; a source power supply node coupled to the coupling element and configured to generate the source power pulses; and a bias power supply node coupled to the substrate holder and configured to generate the bias power pulses.

[0103] Example 15. A plasma processing method comprising: applying a source power pulse to a plasma processing chamber during a first stage, the first stage including a first source power level greater than zero and a first bias power level; applying a bias power pulse to a substrate in the plasma processing chamber during a second stage following the first stage, the second stage including a second source power level less than the first source power level and a second bias power level greater than the second source power level; and reducing the amount of byproducts in the plasma processing chamber during a third stage following the second stage, the third stage including a third source power level less than the first source power level and a third bias power level less than the second bias power level.

[0104] Example 16. The method as described in Example 15, wherein both the third source power level and the third bias power level are substantially zero.

[0105] Example 17. The method as described in one of Examples 15 and 16 further includes: performing the first phase, the second phase, and the third phase cyclically.

[0106] Example 18. The method as described in any one of Examples 15 to 17, wherein the gas flow rate is maintained at a substantially constant value during the first stage, the second stage, and the third stage.

[0107] Example 19. The method as described in any one of Examples 15 to 18, wherein the first stage includes a source pulse sequence at the first source power level.

[0108] Example 20. An apparatus configured to perform the method as described in any one of Examples 15 to 19, the apparatus comprising: a coupling element disposed adjacent to the plasma processing chamber; a substrate holder supporting the substrate; a source power supply node coupled to the coupling element and configured to apply the source power pulse; and a bias power supply node coupled to the substrate holder and configured to apply the bias power pulse.

[0109] Although the invention has been described with reference to illustrative embodiments, this description is not intended to be limiting. Various modifications and combinations of the description, illustrative embodiments, and other embodiments of the invention will be apparent to those skilled in the art. For example, Figures 2 to 4 One or more of the embodiments can be combined in further embodiments. Similarly, regarding Figure 7 The described embodiments can be compared with Figure 8 Combinations. Therefore, it is intended that the appended claims cover any such modifications or embodiments.

Claims

1. A plasma processing method, comprising: The reactive substance control phase includes applying a first source power level to the processing chamber in a pulsed manner to generate ions and free radicals in the plasma; Following the reactive substance control phase, an ion / radical control phase is performed, comprising: reducing the source power applied to the processing chamber from a first source power level to a non-zero specific source power level, and applying a bias power greater than the specific source power level to the substrate in the processing chamber in a pulsed manner; and Following the ion / radical control phase, a byproduct control phase is performed, which includes reducing the source power applied to the processing chamber to a level below the first source power level applied during the reactive substance control phase, and reducing the bias power applied to the substrate to a level below the bias power applied during the ion / radical control phase.

2. The method of claim 1, further comprising: The reactive substance control phase, the ion / radical control phase, and the byproduct control phase are executed cyclically.

3. The method of claim 1, further comprising: Gas is supplied to the processing chamber, wherein the flow rate of the gas is substantially constant during the reactive substance control phase, the ion / radical control phase, and the byproduct control phase.

4. The method of claim 1, wherein: The reactive material control phase further includes applying the bias power to the substrate in a pulsed manner.

5. The method of claim 1, wherein, This byproduct control phase further includes: Throughout the byproduct control phase, the source power is reduced to essentially zero; and Throughout the byproduct control phase, the bias power is reduced to essentially zero.

6. The method of claim 1, wherein, This byproduct control phase further includes: The bias power is applied to the substrate in a pulsed manner to control the redeposition of byproducts on the substrate.

7. A plasma processing apparatus configured to perform the method as claimed in any one of claims 1 to 6, the apparatus comprising: A coupling element is positioned adjacent to the processing chamber; A substrate holder that supports the substrate; A source power supply node, which is coupled to the coupling element and configured to apply the source power in a pulsed manner; as well as A bias power supply node is coupled to the substrate holder and configured to apply the bias power in a pulsed manner.

8. A plasma processing method, comprising: The substrate is processed using a cycle of power pulses, during which a source power pulse is applied to a coupling element and a bias power pulse is applied to a substrate holder supporting the substrate. The cycle of this power pulse includes The first stage includes a first source power level and a first bias power level. The second stage includes a second source power level and a second bias power level, and The third stage includes a third source power level and a third bias power level; Wherein, the first bias power level is greater than zero; The second source power level is lower than the first source power level; Wherein, the second bias power level is greater than the second source power level; Wherein, the power level of the third source is lower than the power level of the first source; and The third bias power level is lower than the second bias power level.

9. The method of claim 8, further comprising repeatedly performing a cycle of the power pulse.

10. The method of claim 8, wherein, The first bias power level is essentially zero.

11. The method of claim 8, wherein, The first bias power level is greater than zero.

12. The method of claim 8, wherein, The third bias power level is greater than zero.

13. The method of claim 8, wherein, Both the third source power level and the third bias power level are essentially zero.

14. A plasma processing apparatus configured to perform the method as claimed in any one of claims 8 to 13, the apparatus comprising: Processing room; A source power supply node, which is coupled to the coupling element and configured to generate these source power pulses; as well as A bias power supply node is coupled to the substrate holder and configured to generate these bias power pulses.

15. A plasma processing method, comprising: During the first phase, a source power pulse is applied to the plasma processing chamber, which includes... The first source power level is greater than zero; as well as First bias power level; During a second phase following the first phase, a bias power pulse is applied to the substrate in the plasma processing chamber, the second phase including... The second source power level is less than the first source power level, and A second bias power level that is greater than the second source power level; as well as During the third phase following the second phase, the amount of byproducts in the plasma processing chamber is reduced. This third phase includes... The third source power level is less than the first source power level, and The third bias power level is less than the second bias power level.

16. The method of claim 15, wherein, Both the third source power level and the third bias power level are essentially zero.

17. The method of claim 15, further comprising: The first phase, the second phase, and the third phase are executed in a loop.

18. The method of claim 15, further comprising: Gas is supplied to the processing chamber at a certain gas flow rate, wherein the gas flow rate is maintained at a substantially constant value during the first stage, the second stage, and the third stage.

19. The method of claim 15, wherein, The first phase includes a sequence of source pulses at the first source power level.

20. A plasma processing apparatus configured to perform the method as claimed in any one of claims 15 to 19, the apparatus comprising: A coupling element is positioned adjacent to the plasma processing chamber; A substrate holder that supports the substrate; A source power supply node, which is coupled to the coupling element and configured to apply the source power pulse; as well as A bias power supply node is coupled to the substrate holder and configured to apply the bias power pulse.

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