Chamber cleaning method

Abstract

A method is provided for cleaning a plasma processing chamber comprising one or more cycles, each cycle comprising performing an oxygen-containing plasma cleaning step, a volatile chemical-type residue cleaning step, and a fluorine-containing plasma cleaning step.

Description

Background Art

[0001] Cross-reference to related applications This application claims the benefit of priority based on U.S. Patent Application No. 63 / 039,303, filed on Jun. 15, 2020, which is hereby incorporated by reference in its entirety for all purposes.

[0002] The description of the background art provided herein is for the purpose of generally presenting the background of the disclosure. The achievements of the inventors named herein, to the extent that they are described in this background art, are not admitted to be prior art to the disclosure, either explicitly or implicitly, including aspects of the description that cannot be regarded as prior art at the time of filing, together with the aspects that are not regarded as prior art to the disclosure.

[0003] The present disclosure relates to a method for manufacturing a semiconductor device. More specifically, the present disclosure relates to a method for cleaning a plasma processing chamber for manufacturing a semiconductor device.

[0004] Metal conductive paths are widely present in via holes and trenches, where metal etching removes multiple types of active or inert metals in order to expose circuit patterns. In addition to interconnections, metal etching has important applications in advanced memory devices. For example, patterning of various magnetic materials in a magnetic random access memory (MRAM) stack remains difficult. Such a stack includes various metal-containing layers. As a result of etching such a stack, various metal residues remain on the plasma-facing surface of the plasma processing chamber after processing.

[0005] Plasma etching processes cause the accumulation of metal residues on the plasma-facing surface of the plasma processing chamber. An effective metal cleaning procedure is required to clean multiple etching species containing metals in both metallic and compound forms, as well as silicon species from the wafer or mask material. Contaminants on the chamber wall surface will cause serious manufacturing problems.

[0006] Therefore, an effective chamber cleaning process becomes important for improving productivity. The current sequential cleaning process has a number of still significant issues that impede the effectiveness of chamber cleaning. SUMMARY OF THE INVENTION

[0007] To achieve the above, in accordance with an object of the present disclosure, there is provided a method for cleaning a plasma processing chamber comprising one or more cycles. Each cycle comprises performing an oxygen-containing plasma cleaning step, performing a volatile chemical type residue cleaning step, and performing a fluorine-containing plasma cleaning step.

[0008] In another embodiment, there is provided a method for processing a plurality of processing wafers in a plasma processing chamber comprising a plurality of cycles. Each cycle comprises processing one of the plurality of processing wafers in the plasma processing chamber and cleaning the plasma processing chamber, the cleaning comprising an oxygen-containing plasma step, a volatile chemical type residue cleaning step, and a fluorine-containing plasma step.

[0009] In the detailed description of the present disclosure made with reference to the accompanying drawings, the above and other features of the present disclosure will be described in detail. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In the accompanying drawings, the present disclosure is illustrated by way of example and not limitation. In these accompanying drawings, like reference numerals are assigned to like components.

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MODE FOR CARRYING OUT THE INVENTION

[0017] Hereinafter, a detailed description of the present disclosure will be given with reference to several preferred embodiments illustrated in the accompanying drawings. In the following description, numerous specific details are set forth in order to facilitate a complete understanding of the present disclosure. However, as will be apparent to those skilled in the art, the present disclosure can be practiced without some or all of these specific details. Also, to avoid unnecessarily obscuring the present disclosure, detailed descriptions of well-known processing steps and / or structures have been omitted.

[0018] Metal conductive paths are widely present in via holes and trenches, where metal etching removes multiple types of active or inert metals to expose circuit patterns. Besides interconnects, metal etching has important applications in advanced memory devices. For example, patterning various magnetic materials within a magnetic random access memory (MRAM) stack remains difficult when such a stack includes titanium nitride (TiN), ruthenium (Ru), copper-iron-boron alloy (CoFeB), magnesium oxide (MgO), cobalt platinum (CoPt), manganese platinum (PtMn), and perhaps other metal-containing layers. Metal residues remaining on chamber walls after various processes include cobalt (Co), iron (Fe), boron (B), platinum (Pt), tantalum (Ta), ruthenium (Ru), molybdenum (Mo), titanium (Ti), manganese (Mn), magnesium (Mg), palladium (Pd), chromium (Cr), iridium (Ir), nickel (Ni), tungsten (W), copper (Cu), and aluminum (Al), among others.

[0019] After metal plasma etching, the process chamber walls are contaminated by multiple etch species containing metals in both metallic and compound forms, and silicon species from the process wafers or mask materials. Contaminants on the chamber walls cause serious problems in IC manufacturing by affecting the chamber plasma conditions and thus the reproducibility between wafers. For etching most metals in MRAM magnetic tunnel junctions (MTJs), halogen chemistries are applied to evaluate the effectiveness of etching. Metals are redeposited onto the chamber walls during wafer processing. X-ray photoelectron spectroscopy of the chamber wall surfaces reveals that most metals are in the form of compounds, such as metal fluorides (MFx, where M is a metal). Furthermore, the surface of the chamber wall is covered with a silicon oxide layer from the process wafers, hard mask materials, or etchants. The mixture of metal / metal compounds and silicon oxide forms a contaminant layer inside the chamber. These contaminants cause serious problems such as flaking of metal particles onto the wafers and process drift by releasing multiple atoms from the chamber walls during wafer processing.

[0020] Therefore, an effective chamber cleaning process becomes important to improve productivity. Currently, a series of metal cleaning chemistries have been developed to remove specific metal species, such as oxygen (O 2 ) plasma for Ru removal, hydrogen gas (H 2 ) plasma for platinum dioxide (PtO 2 ) removal, and Cl 2 / H 2 chemistries for Co and Fe removal. A more comprehensive strategy for contamination removal is to apply in-situ chamber cleaning to the cover wafer automatic cleaning (CWAC) post-etch wafer process. This CWAC process includes sequential steps such as chlorine gas (Cl 2 ), hydrogen gas (H 2 ), nitrogen trifluoride (NF 3 ), and O 2 . Cl 2 plasma is applied to remove metal elements or metal oxides by forming MCl x (M: metal). H2 removes halogen residues and aids in the removal of MF x and MCl x NF can assist in the removal. 3 NF reacts with silicon oxide to reduce the coating material, and the metal can be oxidized to metal oxide to prevent flaking of the particles. However, in the current sequential CWAC process, multiple issues still remain significant and hinder the effectiveness of chamber cleaning: (i) various metals in current IC devices, such as Fe, Co, Pt, copper (Cu), etc., cannot form volatile species with Cl 2 chemical substances, (ii) metal contaminants are embedded in the silicon oxide coating layer. The reactants of the silicon oxide coating layer with the metal removal chemical substances are limited, (iii) NF 3 combustion has the advantage of exposing new metal contaminants by removing the silicon oxide coating, but it is less effective in forming volatile metal species. High metal contamination levels were shown by inductively coupled plasma mass spectrometry (ICPMS) after such sequential CWAC treatment.

[0021] For purposes of understanding, FIG. 1 shows a schematic flowchart of a process utilized in one embodiment. A processed wafer with a stack is placed in a plasma processing chamber (step 104). FIG. 2A is a schematic cross-sectional view showing the stack 200 on a processed wafer processed in one embodiment. The stack 200 is on a substrate having a layer 204 of silicon or silicon oxide (Si / SiO 2 ). A first tantalum (Ta) layer 208 is on the Si / SiO 2 layer 204. A platinum (Pt) layer 212 is on the first tantalum (Ta) layer 208. A cobalt-platinum alloy (CoPt) layer 216 is on the Pt layer 212. A magnesium oxide (MgO) layer 220 is on the CoPt layer 216. A cobalt-iron-boron (CoFeB) layer 224 is on the MgO layer 220. A second Ta layer 228 is on the CoFeB layer 224. A ruthenium (Ru) layer 232 is on the second Ta layer 228. A patterned mask is formed on the stack 200. In this embodiment, the patterned mask is a titanium nitride layer 236 and SiO on it 2It includes layer 240 and the Ru layer 244 thereon.

[0022] Stack 200 is processed (step 108). In this example, the stack undergoes one or more etching processes for etching the stack. FIG. 2B is a schematic cross-sectional view showing stack 200 after the processing of stack 200 is completed. The processing of the stack etches the first Ta layer 208, Pt layer 212, CoPt layer 216, MgO layer 220, CoFeb layer 224, second Ta layer 228, and Ru layer 232. A part of the patterned mask may also be etched. As a result of the processing of stack 200, Ru, SiO 2 , TiN, CoFeB, MgO, CoPt, Pt, and Ta are deposited on the plasma-facing surface of the plasma processing chamber.

[0023] Stack 200 is removed from the plasma processing chamber (step 112). A cover is placed within the plasma processing chamber (step 116). FIG. 3 is a schematic diagram showing an example of a plasma processing chamber system 300 that can be utilized in one embodiment. The plasma processing chamber system 300 includes a plasma reactor 302 having a plasma processing chamber 304 therein. A plasma power supply 306 is regulated by a power matching network 308 and supplies power to a transformer coupled plasma (TCP) coil 310 disposed near a dielectric induction power window 312 to generate a plasma 314 within the plasma processing chamber 304 by supplying inductively coupled power. A Pinnacle (registered trademark) 372 extends from a chamber wall 376 of the plasma processing chamber 304 to the dielectric induction power window 312, forming a Pinnacle ring. The Pinnacle 372 is angled with respect to the chamber wall 376 and the dielectric induction power window 312. For example, the interior angle between the Pinnacle 372 and the chamber wall 376, and the interior angle between the Pinnacle 372 and the dielectric induction power window 312 may each be greater than 90° and less than 180°. The Pinnacle 372 provides an inclined ring near the top of the plasma processing chamber 304, as shown in the figure. The TCP coil (upper power source) 310 may be configured to produce a uniform diffusion profile within the plasma processing chamber 304. For example, the TCP coil 310 may be configured to generate a toroidal power distribution within the plasma 314. The dielectric induction power window 312 is provided to allow energy to pass from the TCP coil 310 to the plasma processing chamber 304 while isolating the TCP coil 310 from the plasma processing chamber 304. A wafer bias voltage power supply 316 regulated by a bias matching network 318 supplies power to an electrode 320 to set a bias voltage when the stack is placed on the electrode 320. A cover 366 is placed on the electrode 320. In this embodiment, the cover 366 is a bare silicon wafer. A controller 324 controls the plasma power supply 306 and the wafer bias voltage power supply 316.

[0024] The plasma power supply 306 and the wafer bias voltage power supply 316 may be configured to operate at a specific high frequency (e.g., 13.56 megahertz (MHz), 27 MHz, 2 MHz, 60 MHz, 400 kilohertz (kHz), 2.54 gigahertz (GHz), or combinations thereof, etc.). The plasma power supply 306 and the wafer bias voltage power supply 316 may have a size appropriate for supplying a certain range of power to achieve the desired processing performance. For example, in one embodiment, the plasma power supply 306 may supply power in the range of 50 to 5000 watts, and the wafer bias voltage power supply 316 may supply a bias voltage in the range of 20 to 2000 volts (V). Further, the TCP coil 310 and / or the electrode 320 may be composed of two or more sub-coils or sub-electrodes. The sub-coils and sub-electrodes may be powered by a single power supply or by a plurality of power supplies.

[0025] As shown in FIG. 3, the plasma processing chamber system 300 further includes a gas source / gas supply mechanism 330. The gas source 330 is in fluid communication with the plasma processing chamber 304 through a gas inlet (such as a gas injector 340). The gas injector 340 may be disposed at any advantageous position within the plasma processing chamber 304 and may take any form for injecting gas. However, preferably, the gas inlet may be configured to produce an "adjustable" gas injection profile. The adjustable gas injection profile allows for independent adjustment of the respective flow rates to a plurality of compartments within the plasma processing chamber 304. More preferably, the gas injector is attached to the dielectric induction power window 312. The gas injector may be attached above, within, or form part of the power window. The process gas and by-products are removed from the plasma processing chamber 304 via a pressure control valve 342 and a pump 344. The pressure control valve 342 and the pump 344 also function to maintain a specific pressure within the plasma processing chamber 304. The pressure control valve 342 can maintain a pressure of less than 1 Torr during processing. An edge ring 360 is disposed around the upper portion of the electrode 320. The gas source / gas supply mechanism 330 is controlled by a controller 324. Kiyo, manufactured by Lam Research Corporation of Fremont, California, may be used to implement one embodiment.

[0026] FIG. 4A is an enlarged cross-sectional view showing a part of the plasma processing chamber 304. In this embodiment, by processing the stack 200, a silicon oxide (SiO 2 )-containing residue layer 408 is deposited on the surface-side portion of the plasma processing chamber 304. In this embodiment, Ru-containing residues 412, volatile chemical type residues 416 (such as iron and / or cobalt-containing residues), and metal halide type residues 420 (such as titanium and / or tin-containing residues) are deposited and embedded in the SiO 2 -containing residue layer 408.

[0027] After the cover 366 is placed inside the plasma processing chamber 304 (step 116), the plasma processing chamber 304 is cleaned (step 120). FIG. 5 is a more detailed flowchart showing the process of the circulation process (step 120) for cleaning the plasma processing chamber 304 in this embodiment. First, an oxygen-containing plasma stage is provided (step 504). In this embodiment, the oxygen-containing gas includes pure oxygen gas (O 2 ). In other embodiments, the oxygen-containing gas may include one or more of O 2 , ozone (O 3 ), carbon monoxide (CO), carbon dioxide (CO 2 ), and water (H 2 O). The oxygen-containing gas is converted into plasma. In this embodiment, the RF generator power is higher than about 500 watts (W) at a frequency of 13.5 megahertz (MHz). The plasma causes some metals to form metal oxides. For example, ruthenium oxide, iron oxide, and cobalt oxide may be formed. The ruthenium oxide may be ruthenium(IV) oxide or ruthenium(VIII) oxide. The chemical reactions for forming examples of these oxides are Ru + O 2 → RuOx, Co + O 2 → CoOx, Fe + O 2 → FeOx, respectively. A portion of the ruthenium oxide becomes volatile and is removed during the oxygen-containing plasma stage. By converting some metals (such as converting iron to iron oxide and cobalt to cobalt oxide), iron and cobalt can be more easily removed in later steps. The flow of the oxygen-containing gas is stopped, and the oxygen-containing plasma stage (step 504) ends.

[0028] FIG. 4B is an enlarged cross-sectional view showing a part of the plasma processing chamber 304 after the oxygen-containing plasma stage (step 504) is completed. A portion of the Ru-containing residue 412 is converted to ruthenium oxide and removed. A portion of the Ru-containing residue 412 is not removed because it is too deeply buried in the SiO 2 -containing residue 408.

[0029] After the oxygen-containing plasma stage (step 504) is completed, a volatile chemical type residue cleaning stage is provided (step 508). In this embodiment, a chlorine-containing gas is flowed into the plasma processing chamber 304. In this embodiment, the chlorine-containing gas is Cl 2 gas and boron trichloride (BCl 3 ) gas. The chlorine-containing gas is converted into plasma. In this embodiment, the RF power is higher than 500 W at a frequency of 13.5 MHz. The plasma causes some metals to form metal chlorides. In this embodiment, Fe and Co are converted into volatile chlorides. Then, the flow of the chlorine-containing gas is stopped.

[0030] In other embodiments, other methods of providing a volatile chemical type residue cleaning stage (step 508) may be provided. Other halogen-containing gases may include at least one of phosphorus trifluoride (PF 3 ), phosphorus trichloride (PCl 3 ), BCl 3 , silicon tetrachloride (SiCl 4 ), titanium tetrachloride (TiCl 4 ), and Cl 2 . In another embodiment, a volatile chemical gas containing at least one of CO, H 2 O, ammonia (NH 3 ), methanol (MeOH), and formic acid is provided. The volatile chemical gas is plasma-ized. The flow of the volatile chemical gas is stopped. Some chemical reactions resulting from exposure to plasma may include: Co / CoO x / CoF x +PCl 3 / PF 3 →Co(PCl 3 )x / Co(PF 3 ) x , Fe / FeO x +SiCl 4 →Fe(SiCl x ) y , Mo+Cl 2 →MoCl x , FeO x / CoO x+MeOH → Fe(CH 2 O) x / Co(CH 2 O) x 、Fe / Co + CO → Fe(CO) x / Co(CO)x。

[0031] In another embodiment of the volatile chemical type residue cleaning step (step 508), plasma-less thermal etching may be provided. During the thermal etching, the plasma processing chamber 304 is heated to a temperature higher than 100 °C. In other embodiments, the plasma processing chamber 304 is heated to a temperature higher than 200 °C. The ligand vapor is flowed into the plasma processing chamber together with the carrier gas, where the ligand vapor forms a ligand complex with at least one of the metal-containing residues (such as iron or cobalt or both). The ligand complex volatilizes at a temperature of at least 100 °C. For example, a vapor containing at least one of acetylacetone (acac) and hexafluoroacetylacetone (hfac) is flowed into the plasma processing chamber 304. Acac and hfac bind to metals (such as Co and Fe) to form compounds such as Fe(acac) x 、Fe(hfac) x 、Co(acac) x 、and Co(hfac) x . The heated plasma processing chamber 304 volatilizes at least one metal-containing residue of those compounds. In other embodiments, the ligand vapor may include a ligand of metal acetylacetonate or amidine. The metal acetylacetonate may include at least one of Sn(acac) 2 、TiCl 2 (acac) 2 、Hf(acac) 4 、Zn(acac) 2 . The amidine may include at least one of butylacetamidine, guanidine, and formamidine. Then, the flow of the ligand vapor is stopped.

[0032] After the volatile chemical type residue cleaning step (step 508) is completed, a volatile chemical type residue pumping out step is provided (step 512). The volatile chemical type residue pumping out step may provide an inert gas (such as argon) and pump out the inert gas together with the volatilized residue. In this embodiment, the volatile chemical type residue pumping out step is plasma-free and may be used to pump out iron-containing residues, cobalt-containing residues, and other free particles. FIG. 4C is an enlarged cross-sectional view showing a part of the plasma processing chamber 304 after the volatile chemical type residue pumping out step (step 512) is completed. A part of the volatile chemical type residue 416 is converted to chloride and removed. In this embodiment, the volatile chemical type residue 416 is a residue containing Mg, Ti, Mo, Cr, Co, and Fe. Iron oxide and cobalt oxide react with chlorine more easily than natural metals of iron and cobalt. Therefore, oxidizing iron and cobalt helps to remove iron and cobalt more easily. Further, free particles of other types of residues may be removed during the volatile chemical type residue pumping out step.

[0033] After the volatile chemical type residue pumping out step (step 512) is completed, a fluorine-containing plasma step is provided (step 516). In this embodiment, the fluorine-containing plasma step (step 516) includes a step of first flowing a fluorine-containing gas into the plasma processing chamber 304. In this embodiment, the fluorine-containing gas contains NF 3 . In other embodiments, the fluorine-containing gas may contain one or more of NF 3 , sulfur hexafluoride (SF 6 ), and carbon tetrafluoride (CF 4 ). The fluorine-containing gas is converted into plasma. In this embodiment, the RF power is higher than 500 W at a frequency of 13.5 MHz. The plasma volatilizes a part of the SiO 2 -containing residue. The flow of the fluorine-containing gas is stopped and the fluorine-containing plasma step (step 516) ends.

[0034] After the fluorine-containing plasma stage (step 516) is completed, fluorine Containing A residue pump-out stage is provided (step 520). The fluorine-containing Residue The pump-out stage may provide an inert gas (such as argon) and pump out the inert gas together with the volatilized residues. FIG. 4D is an enlarged cross-sectional view showing a part of the plasma processing chamber 304 after the fluorine-containing Residue The pump-out stage (step 520) is completed. A part of the SiO 2 containing residue 408 is removed. SiO 2 Removal and pump-out of a part of the containing residue 408 probably removes a part of the Ru-containing residue 412, the volatile chemical type residue 416, and the metal halide type residue 420.

[0035] Fluorine-containing Residue After the pump-out stage (step 520) is completed, a metal halide type residue cleaning stage is provided (step 524). The metal halide type residue 420 is formed from the metal converted to a halide during the volatile chemical type residue cleaning stage (step 508) and the fluorine-containing plasma stage (step 516). In this embodiment, the metal halide type residue cleaning stage (step 524) includes a step of first flowing a hydrogen-containing gas into the plasma processing chamber 304. In this embodiment, the hydrogen-containing gas contains pure H 2 . In other embodiments, the hydrogen-containing gas may contain one or more of H 2 , methane (CH 4 ), and NH 3 . The hydrogen-containing gas is converted into plasma. In this embodiment, the RF power is higher than 500 W at a frequency of 13.5 MHz. The plasma volatilizes a part of the metal halide type residue 420. The flow of the hydrogen-containing gas is stopped and the metal halide type residue cleaning stage (step 524) ends.

[0036] After the metal halide type residue cleaning step (step 524) is completed, a metal halide pump-out step is provided (step 528). The metal halide pump-out step may provide an inert gas (such as argon) and pump out the inert gas together with the volatilized residue. FIG. 4E is an enlarged cross-sectional view showing a part of the plasma processing chamber 304 after the metal halide pump-out step (step 528) is completed. A part of the metal halide type residue 420 is removed. A part of the residue removed during this step is metal-containing residues such as iron, cobalt, titanium, tin, and Si-containing residues.

[0037] It is determined whether to continue the process for another cycle (step 532). The cycle may be repeated until the plasma processing chamber 304 is sufficiently cleaned (for example, until it meets some contamination threshold level). An in-situ endpoint sensor or some other sensor may be used to determine when the plasma processing chamber 304 is sufficiently cleaned. In this example, since residues remain on the plasma processing chamber 304, the process returns to the oxygen-containing plasma step (step 504) and is repeated one or more times. FIG. 4F is an enlarged cross-sectional view showing a part of the plasma processing chamber 304 after the cleaning of the plasma processing chamber 304 (step 120) is completed.

[0038] After the plasma processing chamber 304 is cleaned (step 120), it is determined whether to process another stack 200 (step 124). If another stack 200 is to be processed, the process returns to the step of placing another stack 200 in the plasma processing chamber 304. The cycle may be repeated until all stacks 200 have been processed. When multiple stacks are processed, one or more cycles may be executed. For example, the cycle may be repeated after each stack has been processed, or after a predetermined number of stacks have been processed, or after a predetermined period of time, etc. However, even if only one stack 200 is processed, the cleaning shown in FIG. 5 may be performed to clean the processing chamber (e.g., to maintain the processing chamber in good condition).

[0039] By providing a cyclic process with various cleaning steps, many different metal-containing residues and SiO 2 A mixture of residues is cleaned from the plasma processing chamber 304 so that the plasma processing chamber 304 can process each subsequent stack 200 with less contamination and less variation between stacks.

[0040] In this embodiment, the cover 366 prevents redeposition of residues onto the electrode 320. The cleaning process can generate particles that fall from the dielectric inductive power window 312. Without the cover 366, the particles would fall onto the electrode 320. By using the cover 366, the particles from the dielectric inductive power window 312 fall onto the cover 366 and are removed when the cover 366 is removed. A substrate with the stack 200 is supported by the electrode 320 and electrostatically chucked to the electrode 320. If residues are deposited on the electrode 320 or if the surface of the electrode 320 is damaged by cleaning, the substrate may de-chuck during processing because it cannot be properly chucked. This embodiment has been found to clean the dielectric inductive power window 312 so as to optimize the transmission of RF power through the dielectric inductive power window 312. If the dielectric inductive power window 312 is not cleaned sufficiently, deposits on components of the plasma processing chamber 304 including the dielectric inductive power window 312 can lead to a state where insufficient RF power is transmitted through the dielectric inductive power window 312 and plasma ignition fails.

[0041] Various embodiments may exclude one or more of the cleaning processes shown in FIG. 5, or may perform those processes in a different order, and / or may include additional steps or processes. The particular order of the various cleaning steps can help provide a more efficient cleaning process. For example, the metal halide type residue cleaning step (step 524) may be omitted. In another embodiment, various pumpouts may be omitted. However, the various pumpouts help remove particles before they fall onto components in the lower portions of the plasma processing chamber 304. During a particular step, particles may be undercut and freed before they are volatilized. Such freed particles may fall onto components in the lower portions of the plasma processing chamber 304. The various pumpouts can pump out such particles. In this embodiment, the precoat is not applied after the plasma processing chamber 304 has been cleaned (step 120) and before another stack is placed within the plasma processing chamber 304 (step 104). Over time, residues may accumulate such that the plasma processing chamber 304 must be opened for repair. Various embodiments significantly extend the time during such repairs, and as a result, reduce downtime.

[0042] In various embodiments, the chlorine-containing gas is Cl 2 , BCl 3 , titanium tetrachloride (TiCl 4 ), silicon tetrachloride (SiCl 4 ), trichlorosilane (SiHCl 3 ), dichlorosilane (SiH 2 Cl 2 ), chlorosilane (SiH 3 Cl), and phosphorus trichloride (PCl 3 ) together with phosphorus trifluoride (PF 3 ), may include one or more of. In various embodiments, the ligand vapor may include at least one of acac, hfac, metal acetylacetonate, and amidine.

[0043] FIG. 6 is a schematic block diagram showing a computer system 600 suitable for implementing the controller 324 used in the embodiment. The computer system may have many physical forms, from integrated circuits, printed circuit boards, and small portable devices to large supercomputers. The computer system 600 includes one or more processors 602, and further includes an electronic display device 604 (for displaying images, text, and other data), a main memory 606 (e.g., random access memory (RAM)), a storage device 608 (e.g., hard disk drive), a removable storage device 610 (e.g., optical disk drive), a user interface device 612 (e.g., keyboard, touch screen, keypad, mouse, or other pointing device, etc.), and a communication interface 614 (e.g., wireless network interface). The communication interface 614 enables the transfer of software and data between the computer system 600 and external devices via a link. The system may further include a communication infrastructure 616 (e.g., communication bus, crossover bar, or network) to which the above-described devices / modules are connected.

[0044] The information transferred via the communication interface 614 may be in the form of signals, such as electrical signals, electromagnetic signals, optical signals, or other signals that can be received by the communication interface 614 via a communication link that carries the signal, and may be implemented using wires or cables, optical fibers, telephone lines, mobile phone links, radio frequency links, and / or communication channels. With such a communication interface, it is assumed that one or more processors 602 can receive information from a network or output information to a network when executing the steps of the above-described method. Further, embodiments of the method may be executed by only a processor or may be executed in cooperation with a remote processor that shares part of the processing via a network such as the Internet.

[0045] The term "non-transitory computer-readable medium" is generally used to refer to media such as main memory, secondary memory, removable storage, and storage devices (such as hard disks, flash memories, disk drive memories, CD-ROMs, and other forms of persistent memory), and should not be construed to encompass transient objects such as carrier waves or signals. Examples of computer code include machine code such as code generated by a compiler, and files containing high-level language code that is executed by a computer using an interpreter. A computer-readable medium may also be computer code that is transferred by a computer data signal embodied in a carrier wave and represents a series of instructions executable by a processor.

[0046] Having described the present disclosure with reference to several preferred embodiments above, within the scope of the present disclosure, there exist alternatives, substitutions, modifications, and various alternative equivalents. It should also be noted that there are numerous other aspects for implementing the methods and apparatuses of the present disclosure. Therefore, the appended claims are to be construed as including all such alternatives, substitutions, and various alternative equivalents that fall within the true spirit and scope of the present disclosure. As used herein, the expression "A, B, or C" should be construed to mean the logical (A or B or C) using non-exclusive logical OR, and should not be construed to mean "only one of A or B or C". The present invention can also be realized, for example, in the following aspects. Application Example 1: A method for cleaning a plasma processing chamber, comprising one or more cycles, each cycle comprising i) performing an oxygen-containing plasma cleaning step; and ii) performing a volatile chemical type residue cleaning step; and iii) performing a fluorine-containing plasma cleaning step. A method comprising the steps of Application Example 2: The method of Application Example 1, wherein the cleaning is performed after processing a first wafer in the plasma processing chamber and before processing a second wafer in the plasma processing chamber. Application Example 3: The method of Application Example 1, wherein a cover is disposed in the plasma processing chamber before the cleaning. Application Example 4: The method of Application Example 1, wherein the oxygen-containing plasma cleaning step comprises flowing an oxygen-containing gas into the plasma processing chamber and plasmaizing the oxygen-containing gas. Application Example 5: The method of Application Example 1, wherein the fluorine-containing plasma cleaning step comprises flowing a fluorine-containing gas into the plasma processing chamber and plasmaizing the fluorine-containing gas. Application Example 6: The method of Application Example 1, wherein the cleaning of the plasma processing chamber further comprises a metal halide type residue cleaning step after the fluorine-containing plasma step. Application Example 7: The method of Application Example 6, wherein the metal halide type residue cleaning step comprises flowing a hydrogen-containing gas into the plasma processing chamber; and plasmaizing the hydrogen-containing gas. A method comprising the steps of Application Example 8: The method of Application Example 6, wherein the metal halide type residue cleaning step further comprises a metal halide pump-out. Application Example 9: The method of Application Example 1, wherein the cleaning of the plasma processing chamber further comprises a fluorine residue pump-out step after the fluorine-containing plasma step. Application Example 10: The method of Application Example 1, further comprising a volatile chemical type residue pump-out step after the volatile chemical type residue cleaning step. Application Example 11: The method of Application Example 1, wherein the oxygen-containing plasma step volatilizes ruthenium-containing residues and oxidizes metal-containing residues (such as iron or cobalt). Application Example 12: The method of Application Example 1, wherein the volatile chemical type residue cleaning step comprises: a step of flowing a chlorine-containing gas into the plasma treatment chamber; a step of plasmaizing the chlorine-containing gas. A method comprising the above. Application Example 13: The method of Application Example 12, wherein the chlorine-containing gas is (i) Cl 2 , BCl 3 , TiCl 4 , SiCl 4 , SiHCl 3 , SiH 2 Cl 2 , SiH 3 Cl, or PF 3 , or any combination thereof, and (ii) PCl 3 . A method comprising the above. Application Example 14: The method of Application Example 1, wherein the volatile chemical type residue cleaning step comprises: a step of heating the plasma treatment chamber to a temperature of at least 100 °C; a step of flowing ligand vapor into the plasma treatment chamber. Comprising the above, wherein the ligand vapor forms a ligand complex with at least one metal-containing residue, and the ligand complex volatilizes at a temperature of at least 100 °C. A method comprising the above. Application Example 15: The method of Application Example 14, wherein the ligand vapor comprises at least one of acac, hfac, metal acetylacetonate, and amidine. A method comprising the above. Application Example 16: The method of Application Example 1, wherein the volatile chemical type residue cleaning step comprises: a step of flowing a volatile chemical gas containing CO, H 2 O, MeOH, or formic acid, or any combination thereof, into the plasma treatment chamber; a step of plasmaizing the volatile chemical gas. A method comprising the above. Application Example 17: The method of Application Example 1, wherein the volatile chemical type residue cleaning step comprises: a step of flowing a volatile chemical gas containing CO, H 2 O, NH 3 , methanol (MeOH), or formic acid, or any combination thereof, into the plasma treatment chamber; a step of plasmaizing the volatile chemical gas. A method comprising the above. Application Example 18: The method of Application Example 1, wherein the oxygen-containing gas comprises O 2 、O 3 , CO, CO 2 , or H 2 O, or any combination thereof. A method comprising the above. Application Example 19: The method of Application Example 1, wherein the volatile chemical type residue cleaning step volatilizes at least one metal-containing residue. A method comprising the above. Application Example 20: The method of Application Example 1, wherein the fluorine-containing gas is NF 3 , SF 6 , or CF 4 A method comprising, or any combination thereof. Application Example 21: A method for processing a plurality of processing wafers in a plasma processing chamber, comprising a plurality of cycles, each cycle comprising: a) processing one of the plurality of processing wafers in the plasma processing chamber; b) cleaning the plasma processing chamber, comprising: i) an oxygen-containing plasma stage; ii) a volatile chemical type residue cleaning stage; and iii) a fluorine-containing plasma stage. A method comprising the above. Application Example 22: The method of Application Example 21, further comprising removing the processing wafer from the plasma processing chamber. Application Example 23: The method of Application Example 21, further comprising placing a cover in the plasma processing chamber.

Claims

1. 1. A method for cleaning a plasma processing chamber, comprising one or more cycles, each cycle comprising: i) performing an oxygen-containing plasma cleaning step; ii) performing a volatile chemical type residue cleaning step, heating the plasma processing chamber to a temperature of at least 100° C.; flowing a ligand vapor into the plasma processing chamber, the ligand vapor forming a ligand complex with at least one metal-containing residue, the ligand complex volatilizing at a temperature of at least 100° C.; performing a volatile chemical type residue cleaning step comprising: iii) performing a fluorine-containing plasma cleaning step; A method comprising:

2. 10. The method of claim 1, wherein the cleaning is performed after processing a first wafer in the plasma processing chamber and before processing a second wafer in the plasma processing chamber.

3. The method of claim 1 , wherein a cover is placed in the plasma processing chamber prior to the cleaning.

4. 2. The method of claim 1, wherein the oxygen-containing plasma cleaning step comprises flowing an oxygen-containing gas into the plasma processing chamber and forming the oxygen-containing gas into a plasma.

5. 2. The method of claim 1, wherein the fluorine-containing plasma cleaning step comprises flowing a fluorine-containing gas into the plasma processing chamber and forming the fluorine-containing gas into a plasma.

6. 1. A method for cleaning a plasma processing chamber, comprising one or more cycles, each cycle comprising: i) performing an oxygen-containing plasma cleaning step; ii) performing a volatile chemical type residue cleaning step; iii) performing a fluorine-containing plasma cleaning step; Equipped with The method, wherein the cleaning of the plasma processing chamber further comprises a metal halide type residue cleaning step after the fluorine-containing plasma cleaning step.

7. 7. The method of claim 6, wherein the metal halide type residue cleaning step comprises: flowing a hydrogen containing gas into the plasma processing chamber; generating a plasma from the hydrogen-containing gas; A method comprising:

8. 7. The method of claim 6, wherein the metal halide type residue cleaning step further comprises a metal halide pump-out.

9. 10. The method of claim 1, wherein the cleaning of the plasma processing chamber further comprises a fluorine residue pump-out step after the fluorine-containing plasma cleaning step.

10. 2. The method of claim 1, further comprising a volatile chemical type residue pump-out step after said volatile chemical type residue cleaning step.

11. 10. The method of claim 1, wherein the oxygen-containing plasma cleaning step volatilizes ruthenium-containing residues and oxidizes metal-containing residues (such as iron or cobalt).

12. 2. The method of claim 1, wherein the volatile chemical type residue cleaning step comprises: flowing a chlorine-containing gas into the plasma processing chamber; forming a plasma of the chlorine-containing gas; A method comprising:

13. 13. The method of claim 12, wherein the chlorine-containing gas is: (i) Cl ２ , BCl ３ , TiCl ４ , SiCl ４ , SiHCl ３ , SiH ２ C ２ , SiH ３ Cl or PF ３ or any combination thereof; and (ii) PCl ３ and 14. The method of claim 1, wherein the ligand vapor comprises at least one of acac, hfac, metal acetylacetonate, and amidine.

15. 1. A method for cleaning a plasma processing chamber, comprising one or more cycles, each cycle comprising: i) performing an oxygen-containing plasma cleaning step; ii) performing a volatile chemical type residue cleaning step, The volatile chemical type residue cleaning step comprises: CO, H ２ flowing volatile chemical gases including O, MeOH, or formic acid, or any combination thereof, into the plasma processing chamber; forming a plasma of the volatile chemical gas; performing a volatile chemical type residue cleaning step comprising: iii) performing a fluorine-containing plasma cleaning step; A method comprising:

16. 2. The method of claim 1, wherein the volatile chemical type residue cleaning step comprises: CO, H ２ O, N.H. ３ flowing volatile chemical gases, including methanol (MeOH), or formic acid, or any combination thereof, into the plasma processing chamber; forming a plasma of the volatile chemical gas; A method comprising:

17. 5. The method of claim 4, wherein the oxygen-containing gas is O ２ , O ３ , CO, CO ２ , or H ２ O, or any combination thereof.

18. 10. The method of claim 1, wherein the volatile chemical-type residue cleaning step volatilizes at least one metal-containing residue.

19. 6. The method of claim 5, wherein the fluorine-containing gas is NF ３ , S.F. ６ , or C.F. ４ or any combination thereof.

20. 1. A method for processing a plurality of process wafers in a plasma processing chamber, comprising a plurality of cycles, each cycle comprising: a) processing a process wafer of the plurality of process wafers in the plasma processing chamber; b) cleaning the plasma processing chamber, comprising: i) an oxygen-containing plasma stage; ii) a volatile chemical type residue cleaning step, heating the plasma processing chamber to a temperature of at least 100° C.; flowing a ligand vapor into the plasma processing chamber, the ligand vapor forming a ligand complex with at least one metal-containing residue, the ligand complex volatilizing at a temperature of at least 100° C.; a volatile chemical type residue cleaning stage comprising: iii) comprising a fluorine-containing plasma step; A method comprising:

21. 21. The method of claim 20, further comprising removing the process wafer from the plasma processing chamber.

22. 21. The method of claim 20, further comprising disposing a cover within the plasma processing chamber.

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