How to clean a surface

Abstract

To provide a method for cleaning a substrate.SOLUTION: A method for cleaning a substrate includes supplying a substrate 100 having a dielectric substance 130 and an oxidized metal surface to a reaction chamber, supplying a reductant to the reaction chamber and thus bringing the substrate into contact with the reductant to convert the oxidized metal surface to a metal surface 125, supplying an oxidant to the reaction chamber and thus bringing the substrate into contact with the oxidant to oxidize optional metal contaminants 140 on the surface of the dielectric substance to form oxidized metal contaminants, and supplying a cleaning agent to the reaction chamber and thus bringing the substrate into contact with the cleaning agent to remove the oxidized metal contaminants from the substrate.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure generally relates to methods and systems for cleaning semiconductor substrates. In particular, the present disclosure relates to vapor cleaning for use in the back-end processing of semiconductor substrates.

Background Art

[0002] Semiconductor device processes, such as, in particular, back-end processes, involve the use of metal features such as interconnects. Exemplary metals that can be used include copper and cobalt. Some metals, such as copper, can readily diffuse across surfaces and may cause metal contamination in active device regions and may hinder subsequent selective deposition processes.

[0003] For example, a back-end (BEOL) process may include a copper deposition step, followed by a chemical mechanical polishing step (CMP). After CMP, there may be a waiting time between CMP and the next processing step. During this period, the copper lines may be oxidized, and the oxidized copper may begin to move over the low-k dielectric located between the copper lines. Also, it can complicate subsequent selective deposition processes.

[0004] Metal contamination of dielectrics, such as low-k dielectrics, can also be caused by incomplete selective deposition that results in the formation of small metal grains or metal clusters on the dielectric.

[0005] Metal contaminants on the dielectric, such as caused by metal migration or incomplete selective deposition, can cause reliability, breakdown voltage, leakage current, and / or defect problems.

[0006] Therefore, there is a need for processes that can avoid metal contamination of dielectrics, such as low-k dielectrics, and promote selective deposition.

[0007] The following prior art documents are based on records: Mameli, Alfredo et al., ACS nano 11.9(2017):9303~9311, describes region-selective atomic layer deposition of SiO2 using acetylacetone as a chemoselective inhibitor in an ABC-type cycle; Mameli, A. et al., ACS Applied Materials and Interfaces 10.44(2018):38588~38595, describes isotropic atomic layer etching of ZnO using acetylacetone and O2 plasma; U.S. Patent No. 9991138, describes etching methods and etching apparatus; Zhao, Jing, Mahsa Konh, and Andrew Teplyakov, Applied Surface Science 455(2018):438~445, describes surface chemistry of thermal drying etching of cobalt thin films using hexafluoroacetylacetone. U.S. Patent No. 9991138 describes etching methods and etching apparatus; D. Altieri et al., Journal of Vacuum Science & Technology A 35, 05C203 (2017), describes atomic-scale plasma-surface interactions for metal patterning; U.S. Patent No. 10014212 describes a method for selectively depositing metal films.

[0008] Any explanation of the problems and solutions described in this section is included in this disclosure solely for the purpose of providing background to this disclosure and should not be construed as an acknowledgment that any or all of the explanations were publicly known at the time the invention was made. [Overview of the Initiative]

[0009] Various embodiments of the present disclosure relate to a method for cleaning a substrate, comprising supplying the substrate, including a dielectric and a metal surface, to a reaction chamber, and supplying a cleaning agent to the reaction chamber to bring the substrate into contact with the cleaning agent and remove any metal oxide contaminants from the substrate.

[0010] In some embodiments, the method includes a step of supplying an oxidizing agent to the reaction chamber before supplying a cleaning agent to the reaction chamber. Therefore, a method for cleaning a substrate is described further. This method includes supplying a substrate including a dielectric and a metal surface to a reaction chamber; supplying an oxidizing agent to the reaction chamber, thereby bringing the substrate into contact with the oxidizing agent to oxidize any metal contaminants on the dielectric surface, thus forming metal oxide contaminants; and supplying a cleaning agent to the reaction chamber, thereby bringing the substrate into contact with the cleaning agent, to remove the metal oxide contaminants from the substrate.

[0011] In some embodiments, the method further includes the step of supplying a reducing agent to the reaction chamber before supplying an oxidizing agent to the reaction chamber. Thus, a method for cleaning a substrate is further described, comprising supplying a substrate including a dielectric and a metal oxide surface to a reaction chamber; supplying a reducing agent to the reaction chamber, thereby bringing the substrate into contact with the reducing agent and converting the metal oxide surface to a metal surface; supplying an oxidizing agent to the reaction chamber, thereby bringing the substrate into contact with the oxidizing agent and oxidizing any metal contaminants on the dielectric surface, thus forming metal oxide contaminants; and supplying a cleaning agent to the reaction chamber, thereby bringing the substrate into contact with the cleaning agent and removing the metal oxide contaminants from the substrate.

[0012] In some embodiments, the reducing agent includes an alcohol.

[0013] In some embodiments, the alcohol includes alkyl alcohols.

[0014] In some embodiments, the alkyl alcohol includes ethanol.

[0015] In some embodiments, the oxidizing agent includes an oxygen-containing gas or a mixture of gases.

[0016] In some embodiments, the oxidizing agent includes oxygen.

[0017] In some embodiments, the oxidizing agent is a gas selected from O2, O3, H2O, H2O2, and mixtures thereof.

[0018] In some embodiments, the oxidizing agent is selected from O2, H2O, and mixtures thereof.

[0019] In some embodiments, the oxidizing agent includes O2 plasma.

[0020] In some embodiments, the step of supplying an oxidizing agent to the reaction chamber and the step of supplying a cleaning agent to the reaction chamber are repeated one or more times.

[0021] In some embodiments, the cleaning agent includes β-diketonate.

[0022] In some embodiments, the β-diketonate includes hexafluoroacetylacetone (Hfac).

[0023] In some embodiments, the β-diketonate includes acetylacetone (Hacac).

[0024] In some embodiments, the β-diketonate includes dipivaloylmethane (Hthd).

[0025] In some embodiments, the cleaning agent includes a cyclopentadienyl group.

[0026] In some embodiments, the cleaning agent includes carbon monoxide.

[0027] In some embodiments, the cleaning agent includes carboxylic acid.

[0028] In some embodiments, the cleaning agent includes formic acid.

[0029] In some embodiments, after the step of supplying the cleaning agent to the reaction chamber, a step of supplying an additional oxidizing agent to the reaction chamber follows.

[0030] In some embodiments, the step of supplying additional oxidant to the reaction chamber includes supplying O2 to the reaction chamber in an O2 pulse and supplying H2O to the reaction chamber in an H2O pulse, in the following order.

[0031] In some embodiments, the O2 pulse and the H2O pulse are separated by a purge.

[0032] In some embodiments, the step of supplying a cleaning agent to the reaction chamber and the step of supplying additional oxidant to the reaction chamber are separated by a purge.

[0033] In some embodiments, after the step of supplying a cleaning agent to the reaction chamber, a step of supplying a cleaning residue remover to the reaction chamber follows.

[0034] In some embodiments, the cleaning residue remover contains alcohol.

[0035] In some embodiments, the alcohol is an alkyl alcohol.

[0036] In some embodiments, the alkyl alcohol is selected from methanol, ethanol, isopropanol, and isobutanol.

[0037] In some embodiments, the cleaning residue remover contains additional oxidant.

[0038] In some embodiments, the step of supplying a cleaning residue remover to the reaction chamber includes supplying O2 to the reaction chamber in an O2 pulse and supplying H2O to the reaction chamber in an H2O pulse, in the following order.

[0039] In some embodiments, the O2 pulse and the H2O pulse are separated by a purge.

[0040] In some embodiments, the steps of supplying a cleaning agent to the reaction chamber and supplying a cleaning residue remover to the reaction chamber are separated by purging.

[0041] In some embodiments, the step of supplying a cleaning residue remover to the reaction chamber includes a first sub-step and a second sub-step. The first sub-step includes supplying alcohol to the reaction chamber, and the second sub-step includes supplying an oxidizing agent to the reaction chamber.

[0042] In some embodiments, the alcohol is an alkyl alcohol.

[0043] In some embodiments, the oxidizing agent is an oxygen-containing gas or a mixture of gases.

[0044] In some embodiments, the method further includes the step of purging the reaction chamber after the substrate has been in contact with the cleaning agent.

[0045] In some embodiments, the steps of supplying a reducing agent to the reaction chamber and supplying an oxidizing agent to the reaction chamber are separated by purging.

[0046] In some embodiments, the steps of supplying an oxidizing agent to the reaction chamber and supplying a cleaning agent to the reaction chamber are separated by purging.

[0047] In some embodiments, the method does not involve the use of plasma in a reaction chamber.

[0048] In some embodiments, the method further includes the step of exposing the surface to plasma after the cleaning agent has been supplied to the reaction chamber.

[0049] In some embodiments, the plasma is selected from H2 plasma, N2 / H2 plasma, N2 / Ar plasma, N2 plasma, and NH3 plasma.

[0050] In some embodiments, the steps of supplying the cleaning agent to the reaction chamber and exposing the surface to the plasma are separated by purging.

[0051] In some embodiments, the substrate includes single-crystal silicon.

[0052] In some embodiments, the dielectric surface includes a low dielectric constant dielectric.

[0053] In some embodiments, the metal surface includes a Co surface.

[0054] In some embodiments, the method is carried out at a temperature of at least 100°C to a maximum of 300°C.

[0055] In some embodiments, the metal surface contains Co, and the dielectric surface contains a Co contaminant.

[0056] In some embodiments, the metal surface contains Cu, and the dielectric surface contains a Cu contaminant.

[0057] In some embodiments, the metal surface includes multiple metal wires spaced less than 30 nm apart.

[0058] Furthermore, a method for selectively depositing a material on a substrate including a metal surface and a dielectric surface is further described, comprising the steps of cleaning the substrate by a method described herein, and selectively depositing the material on one of a metal surface and a dielectric surface.

[0059] In some embodiments, the material includes a metal, and the metal is deposited on a metal surface.

[0060] In some embodiments, the metal includes Co.

[0061] In some embodiments, the material includes a polymer.

[0062] In some embodiments, the material includes a dielectric.

[0063] Furthermore, a system comprising one or more reaction chambers, a washing gas source, and a controller is described. In such embodiments, the controller is configured to cause the system to carry out the methods disclosed herein.

[0064] In some embodiments, the system further includes an oxidizing agent source. In such embodiments, the controller is configured to cause the system to transport the oxidizing agent from the oxidizing agent source to the reaction chamber.

[0065] In some embodiments, the system further includes a plasma gas source and a plasma generator. In such embodiments, a controller is configured to cause the system to deliver an oxidizer from the plasma gas source to the reaction chamber. The controller is also configured to operate the plasma generator.

[0066] These embodiments and other embodiments will be readily apparent to those skilled in the art from the following modes for carrying out the invention, which refer to the specific embodiments shown in the accompanying drawings, and the present invention is not limited to any specific embodiments disclosed. [Brief explanation of the drawing]

[0067] A more complete understanding of the exemplary embodiments of this disclosure can be obtained by referring to the modes for carrying out the invention and the claims, as considered in relation to the following illustrated drawings.

[0068] [Figure 1] Figure 1 shows various stages of a substrate undergoing a process according to exemplary embodiments of the present disclosure.

[0069] [Figure 2] Figure 2 illustrates a system according to an embodiment of the present disclosure.

[0070] [Figure 3] Figure 3 illustrates a method according to an embodiment of the present disclosure.

[0071] [Figure 4] Figure 4 illustrates a method according to an embodiment of the present disclosure.

[0072] The following numbering is observed throughout the diagram: 100-Substrate, 110-Single-crystal silicon, 120-Metal layer, 125-Metal surface, 130-Dielectric layer, 140-Metal contaminant, 200-System, 202-One or more reaction chambers, 204-Oxidizing gas source, 206-Cleaning gas source, 208-Purge gas source, 210-Exhaust, 212-Controller, 214-218-Line, 300-Method, 310-Step of supplying substrate to reaction chamber, 320-Step of supplying reducing agent to reaction chamber, 325-Step of purging reaction chamber, 330-Step of supplying oxidizing agent to reaction chamber, 335-Step of purging reaction chamber, 340-Reaction chamber Steps include supplying a cleaning agent, 345 - purging the reaction chamber, 350 - supplying a further oxidizing agent to the reaction chamber, 355 - purging the reaction chamber, 360 - end, 400 - method, 410 - supplying a substrate to the reaction chamber, 420 - supplying a reducing agent to the reaction chamber, 425 - purging the reaction chamber, 430 - supplying an oxidizing agent to the reaction chamber, 435 - purging the reaction chamber, 440 - supplying a cleaning agent to the reaction chamber, 445 - purging the reaction chamber, 450 - supplying a cleaning residue remover to the reaction chamber, 455 - purging the reaction chamber, 460 - end.

[0073] Naturally, the elements in the figures are illustrative for simplification and clarity and are not necessarily drawn to actual size. For example, the dimensions of some of the elements in the figures may be exaggerated relative to others to help improve understanding of the illustrated embodiments of this disclosure. [Modes for carrying out the invention]

[0074] While certain embodiments and examples are disclosed below, it will be understood that the present invention extends beyond the specifically disclosed embodiments and / or uses thereof, as well as their apparent modifications and equivalents. Therefore, the scope of the disclosed invention is not intended to be limited by the specific disclosed embodiments described below.

[0075] This disclosure relates, in general terms, to methods and apparatus for cleaning substrates.

[0076] As used herein, the term “substrate” may refer to any underlying material or material comprising one or more layers, and / or on which one or more layers can be deposited. The substrate may include bulk materials such as silicon (e.g., single-crystal silicon), other Group IV materials such as germanium, or other semiconductor materials such as Group II-VI or Group III-V semiconductor materials. The substrate may include a stack of one or more layers covering the bulk material. Furthermore, the substrate may additionally or alternatively include various features (such as depressions, lines, and the like) formed in or on at least a portion of the layers of the substrate. The method described herein is particularly suitable for cleaning substrates including metallic and dielectric surfaces, i.e., for substrates including exposed metallic and dielectric regions.

[0077] In some embodiments, “film” refers to a layer extending in a direction perpendicular to the thickness direction. In some embodiments, “layer” refers to a material or synonym for film, or a non-film structure, that has a specific thickness formed on a surface. A film or layer may consist of a single film or layer having specific properties, or multiple films or layers, and the boundaries between adjacent films or layers may be clear or not, and may be determined or not based on physical, chemical, and / or any other arbitrary characteristics, formation process or sequence, and / or function or purpose of adjacent films or layers. Furthermore, layers or films may be continuous or discontinuous.

[0078] In this disclosure, “gas” may include materials that are gases, vaporized solids, and / or vaporized liquids under standard conditions, and may also include a single gas or a mixture of gases, depending on the situation. Gases other than process gases, i.e., gases introduced without passing through gas distribution assemblies, e.g., showerheads, other gas distribution devices, etc., may be used, for example, to seal reaction spaces, and may also include sealing gases, e.g., noble gases.

[0079] As used herein, the term “purging” may refer to a procedure in which an inert or substantially inert gas is supplied to a reaction chamber between two pulses of gases that react with each other. For example, purging (e.g., using nitrogen gas) may be supplied between a precursor pulse and a reactant pulse, thereby avoiding or at least minimizing gas-phase interactions between the precursor and reactant. Naturally, purging can be achieved either temporally, spatially, or both. For example, in the case of a primary purge, the purging step can be used chronologically, for example, by supplying a first precursor to the reaction chamber, supplying a purge gas to the reaction chamber, and supplying a second precursor to the reaction chamber, while the substrate on which the layer is deposited does not move. For example, in the case of a spatial purge, the purging step can take the form of moving the substrate from a first position where the first precursor is supplied continuously, through a purge gas curtain, to a second position where the second precursor is supplied continuously. Suitable purge gases include substantially inert gases such as noble gases such as He, Ne, Ar, Xe, and Kr.

[0080] In this disclosure, any two variables can constitute a viable range of those variables, and any range shown may include or exclude endpoints. In some embodiments, any values ​​of the shown variables (whether they are shown as “approximately” or not) may refer to exact or approximate values, may include equivalents, such as mean, median, representative, or majority. Furthermore, in this disclosure, the terms “include,” “constituted by,” and “have” may independently refer to “typically or broadly include,” “include,” “essentially consist of,” or “consist of.” In aspects of this disclosure, the defined meaning of any term does not necessarily exclude the ordinary and customary meanings of that term.

[0081] This specification describes a method for cleaning a substrate. The substrate comprises two distinct regions. In other words, the substrate comprises two distinct surfaces. In particular, the substrate comprises a dielectric surface and a metallic surface. The dielectric surface contains metallic contaminants. The metallic contaminants may have reached the dielectric surface, for example, through surface diffusion from the metallic surface. Alternatively, the metallic contaminants may have been deposited on the dielectric surface in an incomplete selective deposition process. Alternatively, the metallic contaminants may have been deposited on the dielectric surface during a chemical mechanical polishing (CMP) process. The metallic contaminants may, for example, contain copper-containing materials, such as copper or copper oxide particles, on a dielectric such as a low dielectric constant dielectric. The method described herein comprises supplying the substrate to a reaction chamber. Naturally, “metallic surface” refers to the surface of a metallic layer contained within the substrate. Similarly, naturally, “dielectric surface” refers to the surface of a dielectric layer contained within the substrate.

[0082] The method described herein may include supplying an oxidizing agent to the reaction chamber. Thus, the substrate comes into contact with the oxidizing agent, and the metal contaminants are oxidized to form metal oxide contaminants. This step is particularly useful when the metal contaminants on the dielectric surface are in a metallic state, i.e., a non-oxidized state. However, if the substrate contains metal oxide contaminants (which can occur when the substrate is exposed to the atmosphere), the step of supplying an oxidizing agent to the reaction chamber may be omitted.

[0083] Optionally, before contacting the substrate with the oxidizing agent, a reducing agent is supplied to the reaction chamber to bring the substrate into contact with the reducing agent. This may be particularly useful when using substrates such as wafers that contain a metal oxide surface, also called a metal oxide surface layer. Thus, the metal oxide contained in the metal oxide surface is reduced to form a metal, and as a result the metal oxide surface can be converted into a metal surface. Such embodiments can be applied to substrates that are oxidized in an uncontrolled manner, such as being oxidized in the air during a waiting period, which may result in the formation of a metal oxide skin with an unknown variable thickness. Such a metal skin with an uncontrolled thickness, formed on interconnection lines, etc., can be removed during the subsequent step of exposing the substrate to a cleaning agent, thereby creating depressions in the interconnection lines in an uncontrolled manner, i.e., removing material from the interconnection lines in an uncontrolled manner, which may lead to reliability issues, for example. Conversely, the sequence of a first step of exposing the substrate to a reducing agent and a second step of exposing the substrate to an oxidizing agent may appropriately result in the formation of a metal oxide layer having a controlled thickness, for example, at least 1.0 to a maximum of 5.0 nm, which can then be removed in a controlled manner during a subsequent cleaning step. In some embodiments, the reducing agent includes an alcohol. Preferred alcohols include ethanol or alkyl alcohols such as isopropyl alcohol. In some embodiments, the step of supplying the reducing agent to the reaction chamber includes generating an H2 plasma in the reaction chamber and thereby exposing the substrate to the H2 plasma. In other words, in some embodiments, the reducing agent includes an H2 plasma. In some embodiments, the steps of supplying the reducing agent to the reaction chamber and supplying the oxidizing agent to the reaction chamber are separated by purging. Alternatively, the step of supplying the reducing agent to the reaction chamber may occur immediately before the step of supplying the oxidizing agent to the reaction chamber. In other words, and in some embodiments, no purging step occurs between the step of supplying the reducing agent to the reaction chamber and the step of supplying the oxidizing agent to the reducing agent.

[0084] The method includes the step of supplying a cleaning agent to a reaction chamber. Thus, the substrate is brought into contact with the cleaning agent to remove metal oxide contaminants from the substrate. Preferably, the cleaning agent reacts with the metal oxide contaminants to form volatile species, which are then removed from the substrate. Thus, metal oxide contaminants, such as atomic clusters containing metal-oxygen bonds, can be effectively cleaned and removed from the dielectric surface. Advantageously, metal interconnects, such as copper-containing interconnects, can remain substantially unaffected by the cleaning method. In fact, oxidizing agents generally completely oxidize very small metal contaminants, while they substantially do not act on larger metallic features such as copper interconnects; at best, the surface of these features is oxidized, and the oxidized surface, at best, is removed by the cleaning agent along with the metal oxide contaminants.

[0085] In some embodiments, the step of supplying a cleaning agent to the reaction chamber includes multiple cleaning subcycles. A cleaning subcycle includes a cleaning pulse in which the cleaning agent is supplied to the reaction chamber and a purge pulse in which a purge gas is supplied to the reaction chamber. Suitable cleaning agents include β-diketonates. Suitable cleaning agents include halogen-containing compounds. Suitable cleaning agents include halogen-containing β-diketonates. Suitable cleaning agents include fluorine-containing β-diketonates. Suitable cleaning agents include hexafluoroacetylacetone. Suitable cleaning agents include carboxylic acids such as formic acid or ethaneic acid. In some embodiments, the step of supplying a cleaning agent to the reaction chamber includes at least 2 to a maximum of 50 cleaning subcycles, or at least 3 to a maximum of 20 cleaning subcycles, or at least 4 to a maximum of 10 cleaning subcycles. Using multiple cleaning subcycles can advantageously improve cleaning efficiency.

[0086] Cleaning a substrate by the method according to embodiments of this disclosure can, for example, increase the performance of electronic devices fabricated on the substrate. Additionally or alternatively, subsequent selective deposition, depending on the surface chemistry difference between the dielectric surface and the metal surface, can be enhanced. It should be understood that the oxidizing agent can also oxidize the metal surface. The cleaning agent then removes the oxidized metal surface along with the metal contaminants. Nevertheless, this method removes only very small amounts of material from the metal surface, such as metals less than 1 nm thick or less than a single layer of metal. It will also be understood that the dielectric surface remains substantially unaffected during this method for cleaning the substrate, except that contaminants are removed from its surface.

[0087] In some embodiments, the oxidizing agent includes oxygen-containing compounds or gas mixtures. Suitable oxidizing agents include H2O, H2O2, O2, O3, N2O, and mixtures thereof. Particularly good results may be obtained with H2O and H2O2. In some embodiments, air is used as the oxidizing agent. These oxidizing agents can be reacted thermally, i.e., without the use of plasma. Alternatively, plasma may be maintained within the reaction chamber while the oxidizing agent is supplied to the reaction chamber. An example of a plasma-based oxidation treatment is the application of an O2 plasma.

[0088] Optionally, the steps of supplying an oxidizing agent to the reaction chamber and supplying a cleaning agent to the reaction chamber are repeated one or more times. This may be useful, for example, for removing large amounts of metallic contamination from a dielectric surface.

[0089] Various detergents may be suitable. For example, the detergent may contain β-diketonates such as hexafluoroacetylacetone (Hfac), acetylacetone (Hacac), or dipivaloylmethane, i.e., 2,2,6,6-tetramethyl-3,5-heptanedione (Hthd). Alternatively, the detergent may contain cyclopentadienyl groups such as substituted or unsubstituted cyclopentadienyl groups. Exemplary substituted cyclopentadienyl groups include alkyl-substituted cyclopentadienyl groups such as methyl-substituted cyclopentadienyl, ethyl-substituted cyclopentadienyl, isopropyl-substituted cyclopentadienyl, and isobutyl-substituted cyclopentadienyl. Alternatively, the detergent may contain carbonyl groups. In some embodiments, the detergent contains carbon monoxide. In some embodiments, the detergent contains cyclopentadiene. In some embodiments, the detergent contains a mixture of one or more cyclopentadienyl-containing compounds and one or more other carbonyl-containing compounds. In some embodiments, the detergent consists of a mixture of cyclopentadiene and carbon monoxide.

[0090] In some embodiments, the detergent comprises a β-ketoamine, such as acetylacetoneamine or 4-amino-1,1,1,5,5,5-hexafluoropentan-2-one.

[0091] In some embodiments, the detergent comprises a β-dithion or a β-dithioketone. An example of a β-dithion is 1,1,1,5,5,5-hexafluoropentane-2,4-dithion.

[0092] In some embodiments, the detergent contains a β-diimine. An example β-diimine is 1,1,1,5,5,5-hexafluoropentane-2,4-diimine.

[0093] In some embodiments, the detergent includes aminothions, for example, compounds having a thion group and an amine group at the β-position. Exemplary aminothions include 4-amino-3-penten-2-thion and 4-amino-1,1,1,5,5,5-hexafluoropentane-2-thion.

[0094] In some embodiments, the detergent comprises a β-thion imine. In some embodiments, the detergent comprises a β-thioketone imine. A suitable β-thion imine is 1,1,1,5,5,5-hexafluoropentane-2-thion-4-imine.

[0095] In some embodiments, the detergent contains a carboxylic acid. A preferred carboxylic acid is formic acid.

[0096] In some embodiments, the detergent may be supplied to the reaction chamber as a mixture containing the detergent and H2. For example, the detergent may be supplied to the reaction chamber as a gas stream containing at least 10 vol.% H2 to a maximum of 90 vol.% H2, or at least 10 vol.% H2 to a maximum of 30 vol.% H2, or at least 30 vol.% H2 to a maximum of 50 vol.% H2, or at least 50 vol.% H2 to a maximum of 70 vol.% H2, or at least 70 vol.% H2 to a maximum of 90 vol.% H2.

[0097] In some embodiments, the detergent may be supplied to the reaction chamber as a mixture containing the detergent and CO2. For example, the detergent may be supplied to the reaction chamber as a gas stream containing at least 10 vol.% CO2 to a maximum of 90 vol.% CO2, or at least 10 vol.% CO2 to a maximum of 30 vol.% CO2, or at least 30 vol.% CO2 to a maximum of 50 vol.% CO2, or at least 50 vol.% CO2 to a maximum of 70 vol.% CO2, or at least 70 vol.% CO2 to a maximum of 90 vol.% CO2.

[0098] In some embodiments, the detergent may be supplied to the reaction chamber in a gas stream containing at least 10 vol.% to a maximum of 90 vol.% of the detergent, or at least 10 vol.% to a maximum of 30 vol.% of the detergent, or at least 30 vol.% to a maximum of 50 vol.% of the detergent, or at least 50 vol.% to a maximum of 70 vol.% of the detergent, or at least 70 vol.% to a maximum of 90 vol.% of the detergent. The remainder of the gas stream may contain further gases. Exemplary further gases include H2 and CO2.

[0099] Supplying the cleaning agent to the reaction chamber mixed with additional gases such as H2 and CO2 is advantageous in preventing the redeposition of metal contaminants after they have been removed from the substrate using the cleaning agent. The additional gases may be decomposition products of the cleaning agent. If the method or apparatus of this disclosure is not limited to any particular theory or mode of operation, for example, when formic acid is used as a cleaning agent at a temperature of at least 150°C to a maximum of 250°C, or at least 170°C to a maximum of 230°C, it is conceivable that the formic acid may spontaneously decompose into H2 or CO2 during the cleaning process. By mixing the formic acid with one or more of its decomposition products, namely H2 and CO2, it is conceivable that the decomposition of the formic acid may be slowed or prevented, thereby improving cleaning uniformity.

[0100] In an exemplary embodiment, Hfac was used to remove metal oxide contaminants from a substrate containing Co-capped Cu wires, i.e., interconnect wires containing cobalt-covered copper. The substrate further comprises a low-dielectric dielectric in which the Co-capped Cu wires are embedded. The cleaning was performed at 200°C. XPS measurements showed that the metal oxide contaminants were removed from the substrate, while substantially no Co or Cu was removed from the Co-capped Cu wires.

[0101] The method may further include a step of purging the reaction chamber after the substrate has come into contact with the cleaning agent. For example, when Hfac is used as the cleaning agent, the purging step may be useful to remove volatile species such as copper hexafluoroacetylacetonate or cobalt hexafluoroacetylacetonate from the substrate.

[0102] Furthermore, the method may further include supplying plasma into the reaction chamber after the cleaning step to expose the substrate and its surface to the plasma. Optionally, the substrate may be exposed to the plasma after the reaction chamber has been purged. Suitable plasmas include H2 plasma, N2 / H2 plasma, N2 / Ar plasma, N2 plasma, H2 / Ar plasma, N2 / H2 plasma, N2 / Ar, and NH3 plasma. In some embodiments, the plasma is selected from the list consisting of H2 / Ar plasma, N2 / H2 plasma, and N2 / Ar plasma. This may be useful, for example, when the step of contacting the substrate with a cleaning agent leaves residues on the dielectric and / or metallic surfaces of the substrate. For example, when Hfac is used as a cleaning agent, a carbon-fluorine-rich layer may form on the dielectric surface, and a metallic fluoride may form on the metallic surface. These residues can then be adequately removed with any one of the H2 plasma, N2 / H2 plasma, N2 / Ar plasma, N2 plasma, or NH3 plasma. It will be understood that H2 plasma refers to a plasma that uses H2 as the plasma gas. It therefore contains H2 and / or its derived reactive species. Similarly, N2 / H2 plasma refers to a plasma that uses a mixture of N2 / H2 as the plasma gas, N2 / Ar plasma refers to a plasma that uses a mixture of N2 and Ar as the plasma gas, N2 plasma refers to a plasma that uses N2 as the plasma gas, and NH3 plasma refers to a plasma that uses NH3 as the plasma gas. Plasma can effectively remove surface contaminants remaining on dielectric surfaces after the application of cleaning agents. Exemplary surface contaminants that can be removed by plasma include metal fluorides and carbon-fluorine rich layers.

[0103] In some embodiments, the steps of supplying a cleaning agent to the reaction chamber and exposing the surface of the substrate to plasma are separated by purging. In other words, in some embodiments, the steps of supplying a cleaning agent to the reaction chamber and supplying plasma to the reaction chamber to expose the substrate and its surface to plasma can be separated by purging.

[0104] In some embodiments, the step of supplying a cleaning agent to the reaction chamber is followed by the step of supplying a further oxidizing agent to the reaction chamber, thereby exposing the substrate to the oxidizing agent and re-oxidizing the metal surface. The step of supplying a cleaning agent to the reaction chamber may be performed as an alternative to, or in addition to, the step of supplying plasma to the reaction chamber. Supplying a further oxidizing agent to the reaction chamber can effectively remove etching residues such as F or F-containing compounds from the surface of the substrate. Additionally or alternatively, the step of supplying a further oxidizing agent to the reaction chamber can be used as a surface conditioning step before a subsequent selective deposition step.

[0105] In some embodiments, the step of supplying further oxidizing agent to the reaction chamber includes supplying O2 to the reaction chamber with an O2 pulse and supplying H2O to the reaction chamber with an H2O pulse, in the following order. In some embodiments, the O2 pulse and the H2O pulse are separated by purging. Such pulsing sequences can result in particularly reproducible oxidation and desirable OH termination on the resulting oxidized metal surface.

[0106] In some embodiments, the steps of supplying a cleaning agent to the reaction chamber and supplying a further oxidizing agent to the reaction chamber are separated by purging.

[0107] In some embodiments, the method described herein does not use plasma. In other words, in some embodiments, all steps included in the method are thermal. Therefore, in such embodiments, the steps of supplying a reducing agent to the reaction chamber, supplying an oxidizing agent to the reaction chamber, supplying a cleaning agent to the reaction chamber, supplying further oxidizing agents or cleaning residue removers to the reaction chamber, or any purging used in the method do not involve the use of plasma. This may be useful when the substrate contains layers or structures that are susceptible to plasma damage. In other words, avoiding the use of plasma can be an effective way to avoid plasma damage.

[0108] In some embodiments, the step of supplying a cleaning agent to the reaction chamber is followed by the step of supplying a cleaning residue remover to the reaction chamber. Exemplary cleaning residue removers include alcohols. Suitable alcohols include linear, cyclic, or branched alkyl and alkenyl alcohols. Suitable alkyl alcohols include methanol, ethanol, and isopropanol. Suitable cleaning residue removers further include carboxylic acids such as formic acid and ethaneic acid. Thus, excellent cleaning efficiency and excellent process uniformity can be obtained. It should also be noted that alcohols can advantageously remove fluorine surface residues when fluorine-containing cleaning agents such as hexafluoroacetylacetone are used.

[0109] In some embodiments, the step of supplying a cleaning residue remover includes a first sub-step and a second sub-step. The first sub-step includes supplying alcohol to the reaction chamber. Suitable alcohols include linear, cyclic, or branched alkyl and alkenyl alcohols. Suitable alkyl alcohols include methanol, ethanol, and isopropanol. The second sub-step includes supplying an oxidizing agent to the reaction chamber. Suitable oxidizing agents include oxygen-containing gases and mixtures of oxygen-containing gases. In some embodiments, the oxidizing agent is O2. In some embodiments, the first and second sub-steps are separated by purging. Thus, excellent cleaning efficiency and excellent process uniformity can be obtained.

[0110] In some embodiments, the dielectric surface includes a low-dielectric-constant dielectric. Examples of low-dielectric-constant dielectrics include SiOC and SiCN. Alternatively, the dielectric surface may include SiO2, SiN, SiCN, SiC, and / or high-dielectric-constant dielectrics, such as HfO2, ZrO2, and Al2O3.

[0111] In some embodiments, the metal surface includes metals such as Cu, Co, Al, and W. This method is particularly suitable for cleaning substrates whose dielectric surface includes a Co surface containing a Co contaminant. In other embodiments, the metal surface includes Cu, and the dielectric surface includes a Cu contaminant. The metal surface may include multiple metal wires spaced, for example, at intervals of less than 30 nm, e.g., at least 5 nm to a maximum of 10 nm, or at least 10 nm to a maximum of 20 nm, or at least 20 nm to a maximum of 30 nm.

[0112] In some embodiments, the method is carried out at a temperature of at least 100°C to a maximum of 300°C. In advantageous embodiments, the cleaning agent comprises a β-diketonate such as Hfac, and the substrate is in contact with the cleaning agent at a temperature of at least 150°C to a maximum of 250°C, for example, at 200°C.

[0113] A method for selectively depositing a material onto a substrate is further disclosed. The substrate may be one of the substrates described herein and includes metal surfaces and dielectric surfaces. The method includes the steps of cleaning the substrate by the method described herein and selectively depositing the aforementioned material onto one of the metal surfaces or dielectric surfaces. It should be understood that preferred deposition processes that can selectively deposit a material onto a dielectric surface compared to a metal surface, or vice versa, are known in themselves. The selectivity of the deposition process can be improved by performing cleaning as described herein before selective deposition. In a preferred embodiment, surface cleaning and selective deposition are carried out in one identical reaction chamber or in a single system comprising multiple reaction chambers without an intermediate air break.

[0114] In some embodiments, the material to be selectively deposited includes a metal, and the metal is deposited on a metal surface. Exemplary metals that can be deposited include Cu, Co, Ti, W, Ru, Mo, and Al.

[0115] In some embodiments, the material to be deposited includes a polymer. Suitable polymers that can be selectively deposited include polyamides and polyimides.

[0116] In some embodiments, the material to be deposited includes a dielectric. Suitable dielectrics that can be deposited include low-dielectric-constant dielectrics such as silicon oxide, SiOCN, SiOC, SiN, SiCN, and BN, and high-dielectric-constant dielectrics such as HfO2, ZrO2, and Al2O3.

[0117] In some embodiments, the substrate on which the material is selectively deposited includes critical dimensions, for example, line widths of less than 50 nm, less than 40 nm, less than 30 nm, less than 20 nm, or less than 10 nm.

[0118] Furthermore, a system comprising one or more reaction chambers is described. The system further comprises a washing gas source and a controller. The controller is configured to cause the system to carry out the methods described herein. In some embodiments, the system further comprises an oxidizing agent source, and the controller is configured to cause the system to transport the oxidizing agent from the oxidizing agent source to the reaction chambers.

[0119] In some embodiments, the system further includes a plasma gas source and a plasma generator, and a controller is configured to cause the system to transport an oxidizer from the plasma gas source to the reaction chamber. In such embodiments, the controller is further configured to operate the plasma generator.

[0120] In exemplary embodiments, see Figure 1. Figure 1 shows an exemplary substrate (100) that is not to exact scale and undergoes one embodiment of the method described herein. In panel a), the substrate (100) is in its transported state. It comprises single-crystal silicon (110), a metal layer (120) including a metal surface, a dielectric layer (130) including a dielectric surface, and a metallic contaminant (140) located on the dielectric surface.

[0121] In panel b), the substrate is shown after exposure to an oxidizing agent, at which point the metal layer includes a metal oxide surface (125), which is generally very thin, e.g., a single layer, or with a thickness of 0.5–5.0 nm, or 1.0–2.0 nm. The metal contaminants are now completely oxidized, i.e., converted to metal oxide contaminants (140) by exposure to the oxidizing agent. It should also be noted that the substrate may be transported in an oxidized state as shown in panel b), thus eliminating the need to expose the surface to an oxidizing agent.

[0122] In panel c), the substrate is shown after exposure to a cleaning agent that removes metal oxide surfaces and metal oxide contaminants, thus leaving a cleaned substrate including a cleaned metal surface and a cleaned dielectric surface.

[0123] Figure 2 illustrates a system (200) according to an exemplary embodiment of a further disclosure. System (200) may be used to carry out the methods described herein and / or to form a structure or device part described herein.

[0124] In the illustrated embodiment, the system (200) includes one or more reaction chambers (202), an optional oxidizing agent gas source (204), a cleaning agent gas source (206), a purge gas source (208), exhaust (210), and a controller (212). Optionally, the system further includes a plasma gas source and a plasma generator (neither shown).

[0125] The reaction chamber (202) may include any suitable reaction chamber, such as an ALD or CVD reaction chamber.

[0126] The oxidizing agent gas source (204) may include a container and one or more oxidizing agents described herein, either alone or in combination with one or more carrier (e.g., inert) gases. The cleaning agent gas source (206) may include a container and one or more cleaning agents described herein, either alone or in combination with one or more carrier gases. The purge gas source (208) may include one or more inert gases described herein. Although four gas sources (204) to (208) are shown, the system (200) may include any suitable number of gas sources. For example, the system may further include a plasma gas source together with a plasma generator. The gas sources (204) to (208) may be connected to the reaction chamber (202) via lines (214) to (218), each of which may include a flow controller, valves, heaters, etc. Additionally or alternatively, the system may include a reducing agent gas source and / or further oxidizing agent gas sources. If present, a reducing agent gas source (not shown) may include a container containing one or more reducing agents. Alternatively, the reducing agent gas source may include a gas line for transporting one or more reducing agents. If present, an oxidizing agent gas source may include a container containing one or more further oxidizing agents. Alternatively, the oxidizing agent gas source may include a gas line for transporting one or more further oxidizing agents.

[0127] The exhaust source (210) may include one or more vacuum pumps.

[0128] The controller (212) includes electronic circuits and software for selectively operating valves, manifolds, heaters, pumps, and other components included in the system (200). Such circuits and components operate to introduce precursors, reactants, and purge gases from their respective sources (204) to (208). The controller (212) can control the timing of the gas pulse sequence, the temperature of the substrate and / or reaction chamber, the pressure within the reaction chamber, and various other operations to properly operate the system (200).

[0129] The controller (212) may include control software that electrically or pneumatically controls valves to control the flow of reducing agent, oxidizing agent, further oxidizing agent, cleaning agent, plasma gas, and / or purge gas into and out of the reaction chamber (202). The controller (212) may include software or hardware components, such as modules, including FPGAs or ASICs, that perform specific tasks. Advantageously, the modules may be configured to reside on an addressable storage medium of the control system and to perform one or more processes.

[0130] Other configurations of the system (200) are possible, including different numbers and types of oxidizer sources, cleaning agent sources, plasma gas sources, and purge gas sources. Furthermore, it will be understood that there are many arrangements of valves, conduits, oxidizer sources, cleaning agent sources, plasma gas sources, and purge gas sources that can be used to achieve the objective of supplying gas into the reaction chamber (202). In addition, many components have been omitted from the schematic diagram of the system for the sake of simplicity of explanation. Such components may include, for example, various valves, manifolds, purifiers, heaters, vessels, vents, and / or bypasses.

[0131] While the system (200) is operating, a substrate (not shown), such as a semiconductor wafer, is transported, for example, from a substrate handling system to a reaction chamber (202). Once the substrate is transported to the reaction chamber (202), one or more gases from gas sources (204) to (208), such as precursors, reactants, carrier gases, and / or purge gases, are introduced into the reaction chamber (202).

[0132] For further examples, see Figure 3 showing an embodiment of the method described herein (300). Preferably, the method can be carried out at a temperature of at least 100°C to a maximum of 300°C, or at a temperature of at least 150°C to a maximum of 250°C, or at a temperature of 200°C. The method includes the step of supplying a substrate to a reaction chamber (310). The method may then include an optional step (320) of supplying a reducing agent to the reaction chamber. The method may then include an optional step (325) of purging the reaction chamber. The method may then include an optional step (330) of supplying an oxidizing agent to the reaction chamber. The method may then include an optional step (335) of purging the reaction chamber. The method may then include the step (340) of supplying a cleaning agent to the reaction chamber. The method may then include an optional step (345) of purging the reaction chamber. The steps of supplying an oxidizing agent to the reaction chamber (330) and supplying a cleaning agent to the reaction chamber (340) are optionally repeated one or more times. The method may then optionally include a step of supplying further oxidizing agent to the reaction chamber (350). The method may then optionally include a step of purging the reaction chamber (355), after which the method is terminated (360).

[0133] In an exemplary embodiment, an embodiment of the process shown in Figure 4 is described. Preferably, the process can be carried out at a temperature of at least 100°C to a maximum of 300°C, or at a temperature of at least 150°C to a maximum of 250°C, or at a temperature of 200°C. In this embodiment, the method includes the step of supplying a reducing agent to the reaction chamber (420). Preferred reducing agents include alkyl alcohols such as methanol, ethanol, or isopropanol. In one preferred embodiment, ethanol is used as the alkyl alcohol. The reaction chamber is then purged for, for example, at least 1 second to a maximum of 5 seconds (425). Next, the method includes the step of supplying an oxidizing agent to the reaction chamber (430). Preferred oxidizing agents include oxygen-containing gases or gas mixtures. One preferred oxidizing agent is O2. Next, the method includes the step of purging the reaction chamber (435). Next, the method includes the step of supplying a cleaning agent to the reaction chamber (440). Preferred cleaning agents include β-diketonates such as hexafluoroacetylacetone. Next, the reaction chamber is purged (445). In some embodiments, the step of supplying a detergent to the reaction chamber preferably includes a number of cleaning subcycles, each cleaning subcycle including a cleaning pulse in which the detergent is supplied to the reaction chamber and a purge pulse in which a purge gas is supplied to the reaction chamber. In some embodiments, the step of supplying a detergent to the reaction chamber includes at least 2 to a maximum of 20 cleaning subcycles, or at least 3 to a maximum of 10 cleaning subcycles. After the step of supplying a detergent to the reaction chamber, the method includes the step of supplying a cleaning residue remover to the reaction chamber (450). An exemplary cleaning residue remover includes an alcohol, such as an alkyl alcohol. A preferred cleaning residue remover is ethanol. The method then ends (460). In some embodiments, one or more process steps may be carried out at a different temperature than the temperature in which one or more other process steps are carried out. Thus, in some embodiments, one or more steps are carried out at a first temperature and one or more steps are carried out at a second temperature.For example, in some embodiments, the steps of supplying a reducing agent to the reaction chamber (420), supplying a cleaning agent to the reaction chamber (440), and supplying a cleaning residue remover to the reaction chamber (450) can be carried out at a first temperature, and the step of supplying an oxidizing agent to the reaction chamber (430) can be carried out at a second temperature. In some embodiments, the first temperature is different from the second temperature. In some embodiments, the first temperature is higher than the second temperature. In some embodiments, the first temperature is lower than the second temperature. In some embodiments, the first temperature is at least 5°C to a maximum of 50°C higher than the second temperature. In some embodiments, the first temperature is at least 10°C to a maximum of 20°C higher than the second temperature. In some embodiments, the first temperature is at least 5°C to a maximum of 50°C lower than the second temperature. In some embodiments, the first temperature is at least 10°C to a maximum of 20°C lower than the second temperature. In exemplary embodiments, the first temperature is 200°C and the second temperature is 190°C. In exemplary embodiments, the first temperature is 190°C and the second temperature is 200°C.

[0134] In an exemplary embodiment, an embodiment of the process shown in Figure 4 is described. In this embodiment, the method includes the step of supplying a reducing agent to the reaction chamber (420). Preferred reducing agents include methanol, ethanol, or alkyl alcohols such as isopropanol. In one preferred embodiment, ethanol is used as the alkyl alcohol. The reaction chamber is then purged (425). Next, the method includes the step of supplying an oxidizing agent to the reaction chamber (430). Preferred oxidizing agents include oxygen-containing gases or gas mixtures. One preferred oxidizing agent is O2. Next, the method includes the step of purging the reaction chamber (435). Next, the method includes the step of supplying a cleaning agent to the reaction chamber (440). Preferred cleaning agents include β-diketonates such as hexafluoroacetylacetone. β-diketonates such as hexafluoroacetylacetone can be preferably used at a substrate temperature of at least 100°C to a maximum of 300°C, for example, at a temperature of at least 100°C to a maximum of 250°C, for example, at a temperature of 200°C. Next, the reaction chamber is purged (445). In this exemplary embodiment, none of the method steps are repeated. The method then includes supplying a washing residue remover to the reaction chamber (450). The supplying of the washing residue remover preferably includes a first substep and a second substep. The first substep may include supplying an alcohol, such as an alkyl alcohol such as ethanol, to the reaction chamber. Alternatively, the first substep may include supplying a carboxylic acid, such as formic acid or ethaneic acid, to the reaction chamber. The second substep includes supplying an oxidizing agent, such as an oxygen-containing gas or a gas mixture, to the reaction chamber. A preferred oxidizing agent is O2. Optionally, the first and second substeps are separated by purging. The method then ends (460).

[0135] In an exemplary embodiment, an embodiment of the process shown in Figure 4 is described. In this embodiment, the reducing agent is ethanol, the oxidizing agent is O2, the cleaning agent is hexafluoroacetylacetone, and the cleaning residue removal agent comprises a first substep and a second substep. The first substep comprises supplying ethanol to the reaction chamber. The second substep comprises supplying O2 to the reaction chamber. Excellent process uniformity can be obtained using such a process.

[0136] The exemplary embodiments of the Disclosure described above do not limit the scope of the Invention, as these embodiments are merely examples of embodiments of the Invention. Embodiments of any equivalent are intended to be within the scope of the Invention. In fact, various modifications of the Disclosure, in addition to the embodiments shown and described herein, such as alternative useful combinations of the elements described herein, may be apparent to those skilled in the art from the description. Such modifications and embodiments are also intended to be within the scope of the appended claims. [Explanation of Symbols]

[0137] 100 Base material 110 Single-crystal silicon 120 metal layer 125 Metal surface 130 Dielectric layer 140 Metal contaminants 200 Systems 202 Reaction Chamber 204 Oxidizing gas source 205 Gas source 206 Cleaning agent gas source 208 Purge gas source 210 Exhaust 212 Controllers Lines 214, 215, 216, and 218

Claims

1. A method for cleaning a substrate, The process involves supplying a substrate containing a dielectric and a metal oxide surface to a reaction chamber, A reducing agent is supplied to the reaction chamber, thereby bringing the substrate into contact with the reducing agent and converting the metal oxide surface into a metal surface. The process involves supplying an oxidizing agent to the reaction chamber, thereby bringing the substrate into contact with the oxidizing agent, oxidizing any metal contaminants on the dielectric surface, and thus forming metal oxide contaminants. A method comprising supplying a cleaning agent to the reaction chamber, thereby bringing the substrate into contact with the cleaning agent, and removing the metal oxide contaminant from the substrate.

2. The method according to claim 1, wherein the oxidizing agent is an oxygen-containing gas or a gas mixture.

3. The oxidizing agent is O ２ , O ３ H ２ O, H ２ O ２ The method according to claim 1 or 2, wherein the gas is selected from a mixture thereof.

4. The method according to any one of claims 1 to 3, wherein the reducing agent comprises an alcohol.

5. The method according to any one of claims 1 to 4, wherein the cleaning agent comprises a β-diketonate.

6. The method according to any one of claims 1 to 5, wherein the cleaning agent comprises a compound containing a cyclopentadienyl group.

7. The method according to any one of claims 1 to 6, wherein the cleaning agent contains carbon monoxide.

8. The method according to any one of claims 1 to 7, wherein the cleaning agent comprises a carboxylic acid.

9. The method according to any one of claims 1 to 8, wherein the step of supplying a cleaning agent to the reaction chamber is followed by the step of supplying a further oxidizing agent to the reaction chamber.

10. The step of supplying additional oxidant to the reaction chamber is, in the following order, O ２ supplying O to the reaction chamber in O ２ pulses, and H ２ supplying H to the reaction chamber in H ２ O pulses, the method according to claim 9.

11. The method according to any one of claims 1 to 10, wherein the step of supplying a cleaning agent to the reaction chamber is followed by the step of supplying a cleaning residue remover to the reaction chamber.

12. The method according to claim 11, wherein the cleaning residue remover contains alcohol.

13. The method according to claim 12, wherein the alcohol comprises an alkyl alcohol.

14. The method according to claim 13, wherein the alkyl alcohol is selected from methanol, ethanol, isopropanol, and isobutanol.

15. The method according to claim 11, wherein the cleaning residue remover comprises a further oxidizing agent.

16. The step of supplying the cleaning residue remover to the reaction chamber is performed in the following order: ２ A pulse is applied to the reaction chamber. ２ To supply and H ２ O pulse to the reaction chamber H ２ The method according to claim 15, comprising supplying O.

17. The method according to claim 11, wherein the step of supplying a cleaning residue remover to the reaction chamber comprises a first sub-step and a second sub-step, the first sub-step comprising supplying alcohol to the reaction chamber, and the second sub-step comprising supplying an oxidizing agent to the reaction chamber.

18. A method for selectively depositing a material onto a substrate including a metal surface and a dielectric surface, - A step of cleaning the substrate by the method described in any one of claims 1 to 17, A method comprising the step of selectively depositing the material on one of the metal surface or the dielectric surface.

19. The method according to claim 18, wherein the material contains a metal, and the metal is deposited on the metal surface.

20. A system comprising one or more reaction chambers, a cleaning gas source, and a controller, wherein the controller is configured to cause the system to carry out the method according to any one of claims 1 to 19.

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