Area-selective etching

Abstract

The present disclosure relates to a process for selectively etching a material from one surface of a semiconductor substrate across another surface of a semiconductor substrate. The present disclosure further relates to an assembly for etching a material from a surface of a semiconductor substrate. In the process, a substrate including a first surface and a second surface is provided in a reaction chamber, an etching priming reactant is provided in a gaseous state in the reaction chamber, and a reactive species generated from a plasma is provided in the reaction chamber to selectively etch a material from the first surface. The etching priming reactant is deposited on the first surface, and the etching priming reactant comprises a halogenated hydrocarbon. The halogenated hydrocarbon may include a head group and a tail group, and one or both of these may be halogenated.

Description

Technology Field

[0001] The present disclosure generally relates to methods and apparatus for manufacturing semiconductor devices. More specifically, the present disclosure relates to methods and systems for a selective etching process. Background Technology

[0002] Dielectric materials such as silicon oxide and silicon nitride have been used in semiconductors as interlayer insulators for wiring, diffusion barriers, and etching hard masks. Conventional etching processes rely heavily on reactive ion etching (RIE). RIE is advantageous for etching dielectric layers with a thickness of 100 nm or more due to its high etching rate. However, precise control of etch selectivity and uniformity is relatively difficult for etching thinner dielectric materials. Furthermore, conventional processes can damage the underlying material layer, and etching can vary depending on the aspect ratio. Fluorocarbon layers deposited by plasma-assisted CVD are known in the art to enable more controllable etching processes. However, such processes lack specificity and may suffer from process drift. Therefore, there is a need in the art for further development and fine-tuning of etching processes to enable the fabrication of semiconductor devices with additional scalability and versatility.

[0003] Any discussion, including problems and solutions stated in this section, is incorporated into this disclosure solely for the purpose of providing context for the present disclosure. Such discussion should not be construed as any information known at the time the present invention was made or otherwise constitutes the prior art.

[0004] The content of the present invention may introduce a selection of concepts in a simplified form, which may be explained in more detail below. The content of the present invention is not intended to necessarily distinguish the main or essential features of the claimed essence, nor is it intended to be used to limit the scope of the claimed essence.

[0005] Various embodiments of the present disclosure relate to a method for selectively etching material from a first surface of a substrate onto a second surface of a substrate. Embodiments of the present disclosure further relate to an assembly for processing a substrate.

[0006] A method for selectively etching a material from a first surface of a substrate onto a second surface of a substrate according to the present disclosure comprises the steps of providing a substrate including a first surface and a second surface into a reaction chamber, and providing an etching priming reactant in gaseous form into the reaction chamber. The present method further comprises the step of providing a reactive species generated from a plasma into the reaction chamber to selectively etch a material from the first surface. The etching priming reactant according to the present disclosure is deposited on the first surface, and the etching priming reactant comprises a halogenated hydrocarbon.

[0007] In another embodiment, a method for selectively etching material from a first surface of a substrate onto a second surface of a substrate comprises an etching process including the step of forming an etching priming layer on the first surface using a halosilane compound including an aromatic hydrocarbon.

[0008] The present disclosure further relates to an assembly for processing a substrate. The assembly for processing a substrate comprises: a reaction chamber configured and arranged to hold a substrate; an etching priming reactant source configured and arranged to contain and evaporate an etching priming reactant; a plasma generator for generating a plasma; a plasma reactant source for providing gas to the plasma generator; and a reactant injection system configured and arranged to provide the etching priming reactant and plasma in gaseous form from the plasma generator into the reaction chamber.

[0009] In the present disclosure, any two values ​​of a variable may constitute an executable range of said variable, and any indicated range may include or exclude endpoints. Additionally, any value of the indicated variable may refer to an exact value or an approximate value (whether indicated as "approximately"), may include an equivalent, and may refer to an average, median, representative, majority, etc. Also, in the present disclosure, the terms "included," "constituted by," and "having" independently refer to "ordinarily or approximately including," "included," "essentially made up of," or "made up of" in some embodiments. In the present disclosure, any defined meaning does not necessarily exclude the ordinary and conventional meaning in some embodiments. Brief explanation of the drawing

[0010] The accompanying drawings, included to provide further understanding of the present disclosure and to constitute part of this specification, illustrate exemplary embodiments and, together with the description, help to explain the principles of the present disclosure. In the drawings, FIG. 1 is a block diagram illustrating an exemplary embodiment of a method according to the present disclosure. FIG. 2 schematically illustrates an exemplary embodiment of a method according to the present disclosure. FIG. 3 provides an example of an assembly for processing a substrate according to the present disclosure. Specific details for implementing the invention

[0011] The description of the exemplary implementations of the method and assembly provided below is merely illustrative and intended only for illustrative purposes. The following description is not intended to limit the scope or claims of the present disclosure. Furthermore, the reference to multiple embodiments with described features is not intended to exclude other embodiments having additional features or other embodiments including other combinations of the described features. For example, various embodiments are presented as exemplary embodiments and may be referenced in the dependent claims. Unless otherwise noted, exemplary embodiments or their components may be combined or applied separately.

[0012] general details

[0013] In one embodiment, a method for selectively etching material from a first surface of a substrate onto a second surface of a substrate is disclosed. The method comprises the steps of providing a substrate including a first surface and a second surface into a reaction chamber, providing an etching priming reactant in gaseous form into the reaction chamber, and providing a reactive species generated from a plasma into the reaction chamber to selectively etch material from the first surface. The etching priming reactant is deposited on the first surface; the etching priming reactant comprises a halogenated hydrocarbon.

[0014] The etching process according to the present disclosure may be referred to as atomic layer etching. Atomic layer etching (ALE) is a technique comparable to ALD in that separate pulses of one or more reactants are used. However, rather than depositing material as in ALD, in ALE, a thin layer of material is removed controllably using sequential reaction steps. In some embodiments, the sequential reaction steps are self-limiting. In contrast to conventional continuous etching, ALE generally uses one or more etching cycles to remove material. One or more etching cycles may be provided in the ALE process. In some embodiments, the selective etching process according to the present disclosure is a self-limiting process.

[0015] The selective etching process according to the present disclosure may be used to selectively remove material from a substrate surface. The material to be removed may be referred to as the etching target material or the target material. In some embodiments, the target material may be a material contained in the substrate or deposited on the substrate. In some embodiments, the target material is deposited on the substrate for the purpose. In some embodiments, the target material may be an unwanted contaminant on the substrate surface. For example, in some embodiments, the target material to be etched is a parasitic material that has grown undesirably from a region-selective deposition process.

[0016] Etching selectivity can be described by an etching rate, which is the ratio of the etching rate of the material on the first surface to the etching rate of the material on the second surface. In some embodiments, the etching selectivity of the process according to the present disclosure is about 1.5 or greater. For example, the etching selectivity may be about 1.5 to about 1,000, e.g., about 1.5 to about 500, or about 1.5 to about 200, or about 1.5 to about 100, or about 1.5 to about 50, or about 1.5 to about 50, e.g., about 2, about 3, about 5, about 10, or about 20. In some embodiments, the etch selectivity may be about 2 to about 1,000, e.g., about 5 to about 1,000, or about 10 to about 1,000, or about 50 to about 1,000, or about 100 to about 1,000, or about 500 to about 1,000. In some embodiments, the etch selectivity may be about 2 to about 500, e.g., about 5 to about 500, or about 10 to about 200, or about 50 to about 200, or about 20 to about 100, or about 10 to about 100. In some embodiments, the second surface (i.e., the material of the second surface) is not etched. In some embodiments, the second surface is substantially not etched. In some embodiments, the second surface is etched to a smaller extent than the first surface.

[0017] In some embodiments, the current selective etching method is used as part of a vapor deposition process. The deposition process may be optional. In some embodiments, the selective etching step may be performed at one or more intervals in the vapor deposition process. In some embodiments, the selective etching step may be performed after one or more deposition cycles in a periodic vapor deposition process. For example, the selective etching step in a periodic vapor deposition process, such as an atomic layer deposition (ALD) process n It can be performed at every nth deposition cycle, where nis an integer. In some embodiments, the optional etching step may be performed after each cycle in a periodic vapor deposition process such as an ALD process.

[0018] In some embodiments, the selective etching process is a cyclic etching process. In some embodiments, the substrate is in contact with the reactive species described herein for a time sufficient to achieve a desired level of etching in one step. In some embodiments, the etching process is repeated at least once. That is, the step of providing an etching priming reactant into the reaction chamber and the step of providing a reactive species into the reaction chamber may be repeated at least once. The step of providing an etching priming reactant into the reaction chamber and the step of providing a reactive species into the reaction chamber may be referred to as an etching cycle. An etching cycle may include a step of purging the reaction chamber after the step of providing the etching priming reactant and / or after the step of providing a reactive species into the reaction chamber. The number of etching cycles depends on the desired etching depth and the etching rate of the process. The latter can be controlled through process parameters such as ion energy (plasma power, bias power, and pressure) and substrate temperature. In some embodiments, an etching thickness of about 0.5 nm to about 50 nm may be used.

[0019] In some embodiments, the method comprises at least 5 etching cycles. In some embodiments, the method comprises at least 10 or at least 50 etching cycles. In some embodiments, the method comprises at least 100 etching cycles. In some embodiments, the method comprises at least 200 or at least 300 or at least 500 etching cycles. In some embodiments, the method comprises about 5 to about 500 etching cycles. In some embodiments, the method comprises about 5 to about 100 etching cycles, e.g., about 5 to about 50 etching cycles, or about 10 to about 100 etching cycles, or about 50 to about 100 etching cycles. In some embodiments, the method comprises about 50 to about 500 etching cycles, e.g., about 50 to about 200 etching cycles, or about 100 to about 500 etching cycles. In some embodiments, the method includes about 200 to about 500 etching cycles.

[0020] The etching cycle may include a step in which a substrate in a reaction chamber comes into contact with a vapor phase etching priming reactant (also referred to as a reactant or etching reactant). In some embodiments, excess etchant and reaction byproducts from the etching cycle are subsequently removed from the reaction chamber. In some embodiments, this etching cycle may be repeated multiple times. In some embodiments, the etching cycle is repeated sequentially multiple times. In some embodiments, the etching cycle is repeated at intervals of, for example, one, two, or more, in another deposition process, such as a region-selective deposition process.

[0021] In some embodiments, the target material is etched at a rate of about 0.1 Å to about 1 Å per etching cycle, for example, at a rate of about 0.1 Å to about 0.7 Å per etching cycle. In some embodiments, the target material is etched at a rate of about 0.1 Å to about 0.5 Å per etching cycle, or at a rate of about 0.2 Å to about 0.5 Å per etching cycle. In some embodiments, the target material is etched at a rate of about 0.1 Å to about 0.3 Å per etching cycle.

[0022] In some embodiments, the etching priming reactant and the reactive species are provided alternately in sequence within the reaction chamber. In some embodiments, after the step of providing the etching priming reactant within the reaction chamber and / or after the step of providing the reactive species, the reaction chamber is purged.

[0023] In the method according to the present disclosure, the etching priming reactant may be in a gaseous state when in a reaction chamber. The etching priming reactant may be partially gaseous, liquid, or even solid at some point before being provided into the reaction chamber. That is, the etching priming reactant may be solid, liquid, or gaseous in a source vessel or other receptacle, for example, before being delivered into the reaction chamber. When delivery into the reaction chamber is performed, various means of inducing the reactant into a gaseous state may be applied. Such means may include, for example, a heater, an evaporator, the application of a gas flow or reduced pressure, or any combination thereof. Accordingly, the method according to the present disclosure may include the step of heating the etching priming reactant before providing it into the reaction chamber. In some embodiments, the etching priming reactant is heated in a source vessel to at least 30°C, or to at least 40°C, or to at least 50°C, or to at least 100°C. An injector system for injecting an etching priming reactant into a reaction chamber may be heated to improve the vapor phase transfer of the etching priming reactant into the reaction chamber. In some embodiments, the etching priming reactant is not heated. The appropriate temperature may vary depending on the characteristics of the etching priming reactant in question, such as temperature sensitivity and vapor pressure. In some embodiments, the process according to the present disclosure is performed at a temperature of about 20°C to about 120°C. Thus, the temperature within the reaction chamber may be, for example, about 20°C to about 100°C, or about 20°C to about 60°C.

[0024] In the present disclosure, “gas” may include a material that is a gas at normal temperature and pressure (NTP) and, depending on the context, may consist of an evaporated solid and / or evaporated liquid, a single gas, or a mixture of gases. Etching priming reactants may be provided to the reaction chamber in a gaseous state. The term “inert gas” may refer to a gas that does not participate in a chemical reaction and / or does not become part of the layer to a significant extent. Exemplary inert gases include He and Ar and any combination thereof. In some cases, nitrogen and / or hydrogen molecules may be inert gases. Gases other than process gases, such as gases introduced without passing through the precursor injector system, may be used, for example, to seal the reaction space and may include sealing gases.

[0025] The term "purge" or "purging" may refer to a procedure in which gaseous reactants and / or gaseous byproducts are removed from the substrate surface, for example, by exhausting the reaction chamber with a vacuum pump or by replacing the gas inside the reaction chamber with an inert or substantially inert gas such as argon or nitrogen. Purge may be performed between two pulses, for example, between the etching priming reactant and / or reactive species provided within the reaction chamber. Purge may avoid or at least reduce gaseous interactions between gases present in the reaction chamber. It should be understood that purging may affect time or space, or both. For example, in the case of temporal purging, the purging step may be used in a temporal sequence of steps, for example, providing a first precursor, e.g., an etching priming reactant, to the reactor chamber, providing a purging gas to the reactor chamber, and providing a second precursor, e.g., a reactive species generated from plasma, to the reactor chamber, wherein the substrate on which the layer is deposited does not move. In the case of spatial purging, the purging step may take the following form: moving the substrate from a first position where the first reactant is continuously supplied to a second position where the second reactant is continuously supplied through a purging gas curtain. The purging time may be, for example, about 0.01 seconds to about 20 seconds, about 0.05 seconds to about 20 seconds, about 1 second to about 20 seconds, or about 0.5 seconds to about 10 seconds, or about 1 second to about 7 seconds, for example, 5 seconds, 6 seconds, or 8 seconds. However, if necessary, for example when a structure with a very high aspect ratio or other structure having a complex surface shape is processed, a different purging time may be used.

[0026] A reaction chamber according to the present disclosure may be part of a cluster tool in which various different processes are performed in the formation of an integrated circuit. In some embodiments, a flow-type reactor is used. In some embodiments, a cross-flow reactor is used. In some embodiments, a showerhead-type reactor is used. In some embodiments, the reaction chamber may be a space-divided reactor. In some embodiments, the reaction chamber may be a batch-type reactor for manufacturing a number of substrates simultaneously.

[0027] In the selective etching process according to the present disclosure, the first surface and the second surface are chemically distinct. That is, the first surface and the second surface are chemically different from each other in a manner that allows them to be distinguished from one another in the current process.

[0028] As used herein, the term substrate may refer to any underlying material or materials that can be used to form, or upon which an element, circuit, material, or material layer may be formed. The substrate may include a bulk material 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 one or more layers placed over the bulk material. Additionally, the substrate may include various topologies formed within or on at least a portion of the layers of the substrate, such as trenches or spaces between concave, line, or rise sections, such as fins, etc. The substrate may include nitrides, e.g., TiN, oxides, insulating materials, dielectric materials, conductive materials, metals, e.g., tungsten, ruthenium, molybdenum, cobalt, aluminum, or copper, or metallic materials, crystalline materials, epitaxial, heteroepitaxial, and / or single-crystal materials. In some embodiments of the present disclosure, the substrate comprises silicon. In addition to silicon, the substrate may comprise other materials as described above. Other materials may form a layer.

[0029] First surface

[0030] In some embodiments, the first surface (i.e., the material of the first surface) contains oxygen. In some embodiments, the material of the second surface does not contain oxygen. In some embodiments, the material of the first surface contains an oxide. In some embodiments, the material of the second surface does not contain an oxide. In some embodiments, the material of the first surface is essentially composed of, composed of, or includes a metal oxide or a metal oxide. In some embodiments, the metal oxide is a transition metal oxide. Many metals can form oxides in various oxidation states, and as used herein, the term oxide includes all suitable oxidation states. In some embodiments, the metal or metal oxide is selected from the group consisting of hafnium oxide, zirconium oxide, ruthenium oxide, rhenium oxide, niobium oxide, nickel oxide, cobalt oxide, molybdenum oxide, tungsten oxide, titanium oxide, vanadium oxide, chromium oxide, manganese oxide, rhodium oxide, palladium oxide, platinum oxide, copper oxide, or silver, aluminum oxide, and silicon oxide. In some embodiments, the first surface comprises, is essentially composed of, or is made of silicon oxide (e.g., SiO2). The first surface may substantially comprise only silicon oxide, e.g., SiO2. The first surface may comprise a doped oxide, e.g., boron-doped silicon oxide or phosphorus-doped silicon oxide. In some embodiments, the first surface comprises, is essentially composed of, or is made of silicon oxycarbide (e.g., SiOC). In some embodiments, the first surface comprises a silicon oxide layer. The silicon oxide layer is a layer characterized or recognized as a silicon oxide layer. It may contain other elements and impurities such as nitrogen, carbon, hydrogen, etc., and contains these elements to an extent that does not substantially alter the properties of the silicon oxide layer.The silicon oxide layer may include not only a SiO2 layer, but also a SiOC layer, a SiON layer, a SiOCN layer, etc. In some embodiments, the target material is silicon oxide, silicon oxycarbide, silicon oxynitride, or silicon oxynitride. Accordingly, silicon oxide, silicon oxycarbide, silicon oxynitride, or silicon oxynitride may be selectively etched by the method according to the present disclosure.

[0031] In some embodiments, the first surface containing a metal oxide is an oxidized surface of a metallic material. In some embodiments, the first surface containing a metal oxide is formed by oxidizing at least a surface of a metallic material using an oxygen compound such as O3, H2O, H2O2, O2, oxygen atoms, plasma or radicals, or a mixture thereof. In some embodiments, the first surface containing a metal oxide is a natural oxide formed on a metallic material.

[0032] Second surface

[0033] In some embodiments, the second surface contains nitrogen. In some embodiments, the first surface does not contain nitrogen. In some embodiments, the second surface contains a nitride. In some embodiments, the first surface does not contain a nitride. In some embodiments, the second surface contains nitrogen and hydrogen. In some embodiments, the second surface contains silicon nitride, is essentially composed of, or is made of silicon nitride. In some embodiments, the second surface contains silicon carbonitride (SiCN).

[0034] In the present disclosure, SiN is a layer characterized or recognized as a silicon nitride layer that may contain other elements and impurities, such as oxygen, carbon, hydrogen, etc., to the extent that such elements do not substantially alter the properties of the silicon nitride layer. Accordingly, depending on the process recipe, the SiN layer may include not only the SiN layer but also SiNC layers, SiNO layers, SiNCO layers, etc., wherein these layer names are abbreviations generally accepted in the art and are expressed in a non-stoichiometric manner unless otherwise indicated only by the layer type (indicated simply by the primary constituent elements). In some embodiments, SiN has a dielectric constant of about 2 to 10, generally about 4 to 8. In some embodiments, the second surface is not a metal oxide surface. In some embodiments, the second surface is not a metal oxide surface. In some embodiments, the second surface does not substantially contain carbon. In some embodiments, the second surface does not substantially contain oxide.

[0035] A combination of the first surface and the second surface

[0036] The first surface and the second surface are chemically distinct; that is, they exhibit differences in their chemical properties. However, they may both have one or more identical components. For example, both may contain silicon, oxygen, and / or nitrogen. Even if the two surfaces share one or more constituent elements, other constituent elements and / or forms of the surface in which the element in question is present result in chemical distinction. In some embodiments, the first surface and the second surface contain silicon. In some embodiments, the first surface contains silicon oxide and the second surface contains silicon nitride. In some embodiments, the first surface is essentially composed of silicon oxide or is composed thereof, and the second surface is essentially composed of silicon nitride or is composed thereof. In some embodiments, the first surface contains hydroxyl (-OH) groups available to interact with the etching priming reactant. In some embodiments, the second surface has no or substantially no hydroxyl groups available to interact with the etching priming reactant. In some embodiments, the second surface comprises amine (-NH2) groups available to interact with the etching priming reactant. In some embodiments, the first surface has no or substantially no amine groups available to interact with the etching priming reactant. In some embodiments, the first surface is essentially made of silicon oxide, and the silicon oxide is the etching target material.

[0037] In some embodiments, the etching priming reactant is not deposited on the second surface. In some embodiments, the etching priming reactant is substantially not deposited on the second surface. In some embodiments, the etching priming reactant is preferentially deposited on the first surface. In some embodiments, the etching priming reactant is deposited only on the first surface or substantially thereon.

[0038] Without limiting the present disclosure to any specific theory, the etching priming reactant may be selected to have a higher preference for interaction with hydroxyl groups than with amine groups, which may result in the etching priming reactant being selectively deposited on the first surface.

[0039] The first surface and the second surface may each be layers deposited independently on the substrate. However, these, in particular the first surface, may include, be essentially composed of, or be composed of the substrate bulk material.

[0040] Etching priming reactant

[0041] An etch priming reactant according to the present disclosure may be deposited on a first surface. The etch priming reactant may enhance the etching of the first surface. Without limiting the present disclosure to any particular theory, the etch priming reactant may enhance an existing difference in etching rates between the first surface and the second surface so that the first surface is etched faster than the second surface. Alternatively, the etch priming reactant may make the first surface more sensitive to etching and may create a difference in etching rates between the first surface and the second surface that would otherwise not exist. In some embodiments, the first surface may be more resistant to etching in the absence of the etch priming reactant. In some embodiments, the etch priming reactant is chemisorbed on the first surface. In some embodiments, the etch priming reactant forms a self-assembled monolayer on the first surface. In some embodiments, the etch priming reactant includes a head unit for contacting a substrate. In some embodiments, the head unit causes chemisorbation of the etch priming reactant on the substrate surface. In some embodiments, the head is halogenated.

[0042] The etching priming reactant according to the present disclosure comprises a halogenated hydrocarbon. The hydrocarbon may comprise additional functional groups, for example, oxygen, silicon, sulfur, or phosphorus. The size of the etching priming reactant molecule may vary widely. The reactant may also comprise 24 carbon atoms. In some embodiments, the etching priming reactant comprises 2 to 20 carbon atoms. In some embodiments, the etching priming reactant comprises 2 to 16 carbon atoms. In some embodiments, the etching priming reactant comprises 2 to 12 carbon atoms. In some embodiments, the etching priming reactant comprises 2 to 10, or 2 to 8 carbon atoms.

[0043] The head group may include one or more halogen atoms. In some embodiments, the head group includes a third row semimetal or nonmetal and a halogen. "Third row" means the third row of the periodic table as used herein. In some embodiments, the head group includes an oxygen atom. In some embodiments, the oxygen atom is connected to a carbon atom, a silicon atom, a phosphorus atom, or a sulfur atom. In some embodiments, the oxygen atom is connected to a carbon atom, a silicon atom, a phosphorus atom, or a sulfur atom through a double bond. The halogen in the head group may be selected from the group consisting of F, Cl, Br, and I.

[0044] In some embodiments, the head unit contains a third row semimetal or nonmetal. In some embodiments, the third row semimetal or nonmetal is not a halogen. In some embodiments, there is one third row semimetal or nonmetal atom present in the head unit. However, an embodiment may be considered to have two or more third row semimetal or nonmetal atoms within the head unit. One or more halogen atoms may be attached to the third row semimetal or nonmetal atom. In some embodiments, the third row semimetal or nonmetal is selected from the group consisting of silicon, phosphorus, and sulfur.

[0045] In some embodiments, the halogen attached to the silicon atom is a chlorine atom. In some embodiments, the head group comprises an oxygen atom connected to the rest of the molecule through a double bond. In some embodiments, the head group comprises an acyl halide. In some embodiments, the head group comprises a sulfinyl halide. In some embodiments, the head group comprises a phosphonyl dihalide. In some embodiments, the head group comprises a diphenylphosphine halide. In some embodiments, the head group comprises an amine group. In some embodiments, the amine is a primary amine. In some embodiments, the amine is a secondary amine. In some embodiments, the amine is a tertiary amine.

[0046] In some embodiments, the etching priming reactant comprises a head group and a tail group. The head group may be bonded to a first surface. The head group may comprise a halogen atom. The tail group may comprise a halogen atom. In some embodiments, the head group and the tail group comprise a halogen atom. In some embodiments, only the tail group comprises a halogen atom. The halogen atom of the tail group may bring or enhance the etching material of the first surface. In some embodiments, the tail group comprises one or more fluorine atoms for etching the material of the first surface.

[0047] In some embodiments, the head group comprises a substituted silane. In some embodiments, the substituted silane comprises one, two, or three halogens attached to a silicon atom. Thus, in some embodiments, the head group comprises a halosilane. In some embodiments, the head group is a halosilane group. In some embodiments, the halogen in the silane group is selected from the group consisting of F, Cl, Br, and I. In some embodiments, the silane group is monohalogenated. In some embodiments, the silane group is dihalogenated. In some embodiments, the silane group is trihalogenated. In some embodiments, the silane group is a trichlorosilane group. In some embodiments, the silane group is a dichlorosilane group. In some embodiments, the silane group is a tribromosilane group. In some embodiments, the silane group is a dibromosilane group. In some embodiments, the silane group is a trifluorosilane group. In some embodiments, the silane group is a difluorosilane group. In some embodiments, the silane group is a triiodosilane group. In some embodiments, the silane group is a diiodosilane group.

[0048] The silane group can be directly attached to the aromatic ring. Both the silane group and the aromatic ring can be halogenated. For example, the aromatic ring can be fluorinated, and the silane substituent can be chlorinated. In some embodiments, the silane group is attached to the aromatic ring via an aliphatic linker. The linker can be a C1 to C4 carbon chain. The linker can be linear or branched. The silane can be attached to an aliphatic hydrocarbon. That is, the etching priming reactant comprises a silane group and a linear or branched hydrocarbon, and does not comprise an aromatic ring. The silane and the aliphatic hydrocarbon can be multihalogenated.

[0049] In some embodiments, the head group comprises an acyl halide group. In some embodiments, the head group is an acyl halide group (X(C=O)-C, where X is F, Cl, Br, or I). In some embodiments, the acyl halide is an acyl chloride. In some embodiments, the acyl halide is an acyl fluoride. In some embodiments, the acyl halide is an acyl bromide. In some embodiments, the acyl halide is an acyl iodine. In some embodiments, the head group comprises a sulfinyl halide. In some embodiments, the head group is a sulfinyl halide (X(S=O)-C, where X is F, Cl, Br, or I). In some embodiments, the sulfinyl halide is a sulfinyl chloride. In some embodiments, the sulfinyl halide is a sulfinyl fluoride. In some embodiments, the head group comprises a sulfonyl halide X(S(=O)2)-C, where X is F, Cl, Br, or I. In some embodiments, the head group is a sulfonyl halide. In some embodiments, the sulfonyl halide is a sulfonyl chloride. In some embodiments, the sulfonyl halide is a sulfonyl fluoride. In some embodiments, the head group comprises a phosphon dihalide (X2(P=O)-C, where X is F, Br, or I). In some embodiments, the head group is a phosphon dihalide. In some embodiments, the phosphon dihalide is a phosphon dichloride. In some embodiments, the phosphon dihalide is a phosphon difluoride. In some embodiments, the phosphon acid is a phosphon dibromide. In some embodiments, the head group comprises a diphenylphosphine halide, such as diphenylphosphine chloride.

[0050] A head group is connected to a tail group. The tail group may comprise a halogenated hydrocarbon. The halogenated hydrocarbon may be a C1 to C10 linear or branched hydrocarbon. The halogenated hydrocarbon may be an aromatic hydrocarbon. In some embodiments, the halogenated hydrocarbon is a C1 to C3 hydrocarbon. In some embodiments, the halogenated hydrocarbon is an unsaturated hydrocarbon. Unless the present disclosure is limited by any particular theory, shorted hydrocarbon chains may result in less carbon deposition on the substrate during the process. In some embodiments, the head group is directly connected to the tail group. Thus, the halogenated hydrocarbon attached to the head group is the tail group. The tail group may comprise a halogenated hydrocarbon. For example, a diphenylphosphine halide tail group may be connected to the head group through one of the phenyl rings.

[0051] The etching priming reactant according to the present disclosure comprises a halogenated hydrocarbon. The halogenated hydrocarbon may constitute a tail group. In some embodiments, the tail group comprises a halogenated hydrocarbon. In some embodiments, the tail group is a halogenated hydrocarbon. The halogenated hydrocarbon may comprise a C1 to C12 hydrocarbon. Thus, the hydrocarbon may contain 1 to 12 carbon atoms. For example, the hydrocarbon may contain 2 carbon atoms, 3 carbon atoms, 4 carbon atoms, 5 carbon atoms, 6 carbon atoms, or 7 carbon atoms, or 8 carbon atoms, or 9 carbon atoms, or 10 carbon atoms, or 11 carbon atoms. In some embodiments, all carbon atoms of the halogenated hydrocarbon are halogenated. In some embodiments, one carbon atom of the halogenated hydrocarbon is not halogenated. Unless otherwise specified, the term "halogenated hydrocarbon" refers to a hydrocarbon containing at least one halogen atom. Thus, the halogenated hydrocarbon contains at least one carbon atom to which at least one halogen atom is attached. The halogenated carbon atom may contain one, two, or three halogen atoms at the end of the carbon chain. In some embodiments, two carbon atoms of the halogenated hydrocarbon are not halogenated. In some embodiments, three carbon atoms of the halogenated hydrocarbon are not halogenated. In some embodiments, four carbon atoms of the halogenated hydrocarbon are not halogenated. In some embodiments, the halogenated hydrocarbon contains one halogenated carbon atom. In some embodiments, the halogenated hydrocarbon comprises two halogenated carbon atoms. In some embodiments, the halogenated hydrocarbon comprises three halogenated carbon atoms. In some embodiments, the halogenated hydrocarbon comprises four halogenated carbon atoms. In some embodiments, the halogenated hydrocarbon comprises five halogenated carbon atoms.In some embodiments, the halogenated hydrocarbon comprises six halogenated carbon atoms. In some embodiments, the halogenated hydrocarbon comprises seven halogenated carbon atoms.

[0052] In some embodiments, the halogenated hydrocarbon is selected from fluorinated hydrocarbons, chlorinated hydrocarbons, brominated hydrocarbons, and iodinated hydrocarbons, or mixtures thereof. In some embodiments, the halogenated hydrocarbon contains fluorine (F) and chlorine (Cl). In some embodiments, the halogenated hydrocarbon contains F and bromine (Br). In some embodiments, the halogenated hydrocarbon contains F and iodine (I). In some embodiments, the halogenated hydrocarbon contains Cl and Br. In some embodiments, the halogenated hydrocarbon contains Cl and I. In some embodiments, the halogenated hydrocarbon contains Br and I.

[0053] In some embodiments, the halogenated hydrocarbon comprises a halogenated aromatic hydrocarbon. In some embodiments, the halogenated hydrocarbon comprises an aromatic hydrocarbon, wherein the aromatic ring is halogenated. In some embodiments, all halogenated carbon atoms of the halogenated hydrocarbon are within the aromatic ring. The aromatic ring may be a ring having five members. The aromatic ring may be a ring having six members. The aromatic ring may be a fused aromatic ring. The aromatic ring may be a furanyl ring. The aromatic ring may be a pyrrolyl ring. The aromatic ring may be a phenyl ring.

[0054] The aromatic ring may be polyhalogenated. In some embodiments, the aromatic ring comprises five halogen atoms. In some embodiments, the aromatic ring comprises four halogen atoms. In some embodiments, the aromatic ring comprises three halogen atoms. In some embodiments, the aromatic ring comprises two halogen atoms. In some embodiments, the aromatic ring comprises one halogen atom. In some embodiments, the aromatic ring is polyfluorinated. In some embodiments, the aromatic ring is polychlorinated. In some embodiments, the aromatic ring is polybrominated. In some embodiments, the aromatic ring is polyiodinated. In some embodiments, the aromatic ring is polyiodinated. In some embodiments, the halogenated hydrocarbon comprises a pentafluorophenyl group. In some embodiments, the halogenated hydrocarbon comprises pentachlorophenyl. In some embodiments, the halogenated hydrocarbon comprises pentabromophenyl. In some embodiments, the halogenated hydrocarbon comprises pentaiodophenyl. In some embodiments, the aromatic ring comprises another substituent in addition to the halogen.

[0055] In some embodiments, the halogenated hydrocarbon comprises an aliphatic hydrocarbon. In some embodiments, the aliphatic hydrocarbon is a linear hydrocarbon. In some embodiments, the aliphatic hydrocarbon is a branched hydrocarbon. In some embodiments, the halogenated hydrocarbon is an aliphatic hydrocarbon. That is, in some embodiments, the halogenated hydrocarbon does not contain an aromatic moiety. The aliphatic hydrocarbon may be a C1 to C12 hydrocarbon, for example, a C2 hydrocarbon, a C3 hydrocarbon, a C4 hydrocarbon, a C5 hydrocarbon, a C6 hydrocarbon, a C7 hydrocarbon, a C8 hydrocarbon, or a C9 hydrocarbon. The aliphatic halogenated hydrocarbon may be polyhalogenated. One or more carbon atoms of the aliphatic hydrocarbon may be bonded to one, two, or three halogen atoms. In some embodiments, the aliphatic hydrocarbon comprises two halogen atoms attached to the same or different carbon atoms. In some embodiments, the aliphatic hydrocarbon comprises three halogen atoms attached to the same or different carbon atoms. In some embodiments, the aliphatic hydrocarbon comprises four halogen atoms attached to two or more carbon atoms. In some embodiments, the aliphatic halogenated hydrocarbon comprises five halogen atoms attached to two or more carbon atoms. In some embodiments, the aliphatic hydrocarbon comprises six halogen atoms attached to three or more carbon atoms. In some embodiments, the aliphatic hydrocarbon comprises seven halogen atoms attached to three or more carbon atoms. In some embodiments, the aliphatic hydrocarbon comprises eight halogen atoms attached to four or more carbon atoms. In some embodiments, the aliphatic hydrocarbon comprises nine halogen atoms attached to four or more carbon atoms. In some embodiments, the aliphatic hydrocarbon comprises ten halogen atoms attached to five or more carbon atoms. In some embodiments, the aliphatic hydrocarbon comprises eleven halogen atoms attached to five or more carbon atoms.In some embodiments, the aliphatic hydrocarbon comprises twelve halogen atoms attached to six or more carbon atoms. In some embodiments, the aliphatic hydrocarbon comprises thirteen halogen atoms attached to six or more carbon atoms. In some embodiments, the aliphatic hydrocarbon comprises fourteen halogen atoms attached to seven or more carbon atoms. In some embodiments, the aliphatic hydrocarbon comprises fifteen halogen atoms attached to seven or more carbon atoms. In some embodiments, the aliphatic hydrocarbon comprises sixteen halogen atoms attached to eight or more carbon atoms. In some embodiments, the aliphatic hydrocarbon comprises seventeen halogen atoms attached to eight or more carbon atoms. In some embodiments, the aliphatic hydrocarbon may comprise eighteen, nineteen, twenty or more halogen atoms arranged similarly.

[0056] In some embodiments, all atoms except one carbon atom of the aliphatic hydrocarbon are halogenated. In some embodiments, all atoms except two carbon atoms of the aliphatic hydrocarbon are halogenated. In some embodiments, all atoms except three carbon atoms of the aliphatic hydrocarbon are halogenated. In some embodiments, all atoms except one carbon atom of the aliphatic hydrocarbon are completely halogenated. In some embodiments, all atoms except two carbon atoms of the aliphatic hydrocarbon are completely halogenated. In some embodiments, all atoms except three carbon atoms of the aliphatic hydrocarbon are completely halogenated. A completely halogenated carbon atom refers to a carbon atom that does not contain any bond to hydrogen and bonds only to the halogen atom and other carbon atoms.

[0057] The halogen atom of the aliphatic hydrocarbon may be the same halogen or a different halogen. In some embodiments, the aliphatic hydrocarbon is fluorinated. In some embodiments, the aliphatic hydrocarbon is chlorinated. In some embodiments, the aliphatic hydrocarbon is brominated. In some embodiments, the aliphatic hydrocarbon is iodinated.

[0058] In some embodiments, the etching priming reactant may have the chemical formula (Ia), and

[0059] Y3Si(CH a X b ) n CH c X d , chemical formula (Ia)

[0060] Here, Y is selected from the group consisting of Cl, F, Br, I, and NR2 (where R is H or a C1 to C3 alkyl), and X is selected from the group consisting of Cl, F, Br, and I, and a is 0, 1, or 2, and b is 2 - a and, c is 0, 1, 2 or 3, and d is 3 - c And, n It is 0 to 11. a and b is selected independently for each carbon. X and Y may be the same or different. In some embodiments, X and Y are F. In some embodiments, X and Y are Cl. In some embodiments, X is F and Y is Cl. In some embodiments, X is F and Y is Cl. In some embodiments, X is F and Y is Br.

[0061] Accordingly, in some embodiments, the etching priming reactant may have the chemical formula (Ib), and

[0062] Y3Si(CH2) a (CX2) b CH c X d , chemical formula (Ib)

[0063] Here, Y is selected from the group consisting of Cl, F, Br, I, and NR2 (where R is H or a C1 to C3 alkyl), and X is selected from the group consisting of Cl, F, Br, and I, and a and b is an integer from 0 to 11, but a + b ≤ 11 and, c is 0, 1, 2, or 3, and d is 3 to c. X and Y may be the same or different. In some embodiments, X is F and Y is Cl. In some embodiments, X is F and Y is Br. In some embodiments, X is F and Y is I. In some embodiments, X is Cl and Y is Br. In some embodiments, X is Cl and Y is F. In some embodiments, X is F and Y is Br. In some embodiments, X is F and Y is F. In some embodiments, X is Cl and Y is Cl. In some embodiments, a is 0, b is 0, X is F, and Y is NH2. In some embodiments, a is 0, b is 0, X is F, and Y is N(CH3)2. For example, the etching priming reactant may include trichloro(1H,1H,2H,2H-perfluorooctyl)silane, namely Cl3Si(CH2)2(CF2)5CF3 (CAS nro 78560-45-9). In some embodiments, the etching priming reactant may include [2-(perfluoropentyl)ethyl]trichlorosilane, namely Cl3Si(CH2)2(CF2)4CF3 (CAS nro 229499-00-7). In some embodiments, the etching priming reactant may include [2-(perfluorobutyl)ethyl]trichlorosilane, namely Cl3Si(CH2)2(CF2)3CF3 (CAS nro 78560-47-1).

[0064] In some embodiments, the etching priming reactant may have a structure according to the formula (II), and

[0065]

[0066] In some embodiments, the etching priming reactant may have a structure according to the formula (III), and

[0067]

[0068] In some embodiments, the etching priming reactant may have a structure according to the formula (IV), and

[0069]

[0070] In some embodiments, the etching priming reactant may have a structure according to the chemical formula (V), and

[0071]

[0072] In formulas (II) to (Vb), R is a C1 to C12 linear, branched, cyclic, or aromatic hydrocarbon as described above, Y is selected from the group consisting of Cl, F, Br, I, and NR'2 (where R' is H or a C1 to C3 alkyl), and X is selected from the group consisting of Cl, F, Br, and I. R may comprise one or more halogens attached to one or more carbons, and the halogens are selected from the group consisting of F, Cl, Br, and I. In some embodiments, one or more halogens in R are F and Y is Cl. X and Y may be the same or different. In some embodiments, one or more halogens in R are F and Y is Cl.

[0073] In some embodiments, the etching priming reactant may have a structure according to the chemical formula (VI):

[0074]

[0075] In formula (VI), Y is selected from the group consisting of Cl, F, Br, I, and NR'2 (wherein each R' is independently H or a C1 to C3 alkyl), and each X is independently selected from the group consisting of H, Cl, F, Br, and I, so that at least one X is a halogen (i.e., not H). In some embodiments, at least one X is F and Y is Cl. In some embodiments,

[0076] For example, the etching priming reactant according to formula (II) may be Cl-(C=O)-CH2-CF3, or Cl-(C=O)-CF3, or Cl-(C=O)-PhF5, (Ph represents a phenyl ring). In another example, the etching priming reactant according to formula (III) may be Cl-(S=O)-CH2-CF3, or Cl-(S=O)-CF3, or Cl-(S=O)-PhF5. In another example, the etching priming reactant according to formula (IV) may be Cl-(S(=O)2)-CH2-CF3, or Cl-(S(=O)2)-CF3, or Cl-(S(=O)2)-PhF5. In another embodiment, the etching priming reactant according to formula (V) may be Cl2-(P=O)-CH2-CF3, or Cl2-(P=O)-CF3, or Cl2-(P=O)-PhF5.

[0077] In some embodiments, the etching priming reactant may have the chemical formula (VII):

[0078]

[0079] Herein, X is selected from F, Cl, Br, and I, R is a C1 to C6 aliphatic hydrocarbon, e.g., a C3 to C6 aliphatic hydrocarbon, and Y is selected from the group consisting of F, Cl, Br, I, and NR'2, where R' is H or a C1 to C3 alkyl. In some embodiments, all X and all Y are each the same, provided that at least one X is a halogen. For example, R may be -CH2- (Formula VIII), or -CH2-CH2- (Formula IX), or -CH2-CH2-CH2- (Formula X), or -CH(CH3)-CH2- (Formula XI), or -CH(CH2-CH3)- (Formula XII). In some embodiments, X is F and Y is Cl. In some embodiments, X is F and Y is Br. In some embodiments, X is F and Y is I. In some embodiments, X is Cl and Y is Br. In some embodiments, X is Cl and Y is F. In some embodiments, X is F and Y is Br. In some embodiments, X is F and Y is F. In some embodiments, X is Cl and Y is Cl. In some embodiments, the alkyl linker comprises one or more halogen atoms.

[0080]

[0081] In some embodiments, the etching priming reactant may comprise 1,2,3,4,5-pentafluoro-6-[1-(trichlorosilyl)propyl]benzene (CAS nro 1233509-66-4). In some embodiments, the etching priming reactant may comprise 1,2,3,4,5-pentafluoro-6-[3-(trichlorosilyl)propyl]benzene (CAS nro 78900-02-4). In some embodiments, the etching priming reactant may comprise trichloro(1H,1H,2H,2H-perfluorooctyl)silane (CF3(CF2)5CH2CH2SiCl3).

[0082] plasma

[0083] In the method according to the present disclosure, plasma is used to generate reactive species. Reactive species may be generated from plasma generated by RF. Reactive species may be generated, for example, by inductively coupled plasma (ICP), capacitively coupled plasma (CCP), or microwave plasma. Reactive species according to the present disclosure may include ions and / or radicals.

[0084] In some embodiments, the reactive species are generated from a hydrogen-containing plasma. In some embodiments, the reactive species are generated from a nitrogen-containing plasma. In some embodiments, the reactive species are generated from a noble gas-containing plasma. In some embodiments, the reactive species are generated from an argon-containing plasma. In some embodiments, the reactive species are generated from a helium-containing plasma. In some embodiments, the reactive species are generated from a krypton-containing plasma. In some embodiments, the reactive species are generated from a xenon-containing plasma. In some embodiments, the reactive species are generated from plasma-containing hydrogen and nitrogen. In some embodiments, the reactive species are generated from plasma-containing noble metals and nitrogen. In some embodiments, the reactive species are generated from plasma-containing argon and nitrogen. In some embodiments, the reactive species are generated from plasma-containing helium and nitrogen. In some embodiments, the reactive species are generated from plasma-containing krypton and nitrogen. In some embodiments, the reactive species are generated from plasma-containing xenon and nitrogen.

[0085] In some embodiments, the plasma is generated from a gas containing substantially only hydrogen. In some embodiments, the plasma is generated from a gas containing substantially only nitrogen. In some embodiments, the plasma is generated from a gas containing substantially only noble gas. In some embodiments, the plasma is generated from a gas containing substantially only argon. In some embodiments, the plasma is generated from a gas containing substantially only helium. In some embodiments, the plasma is generated from a gas containing substantially only nitrogen and hydrogen. In some embodiments, the plasma is generated from a gas containing substantially only nitrogen and noble metals. In some embodiments, the plasma is generated from a gas containing substantially only nitrogen and argon.

[0086] The plasma power generated by RF may vary in different embodiments of the present disclosure. In some embodiments, the plasma is generated by applying RF power of about 10 W to about 1,000 W, or 50 W to about 1,000 W, or about 100 W to about 500 W. In some embodiments, the RF power density is about 0.02 W / cm² 2 Up to about 2.0 W / cm 2 , or about 0.05 W / cm 2 Approximately 1.5 W / cm 2 RF power may be applied to a gas flowing during the plasma pulse time, continuously flowing through a reaction chamber and / or flowing through a remote plasma generator. Thus, in some embodiments, radical species may be formed remotely ("remote plasma") away from the substrate or reaction space via a plasma discharge. In some embodiments, radical species may be formed near the substrate or directly on the substrate ("direct plasma"). In some embodiments, the plasma power is 50 W.

[0087] Etching cycle

[0088] In some embodiments, the method comprises one or more etching cycles. Each etching cycle may include the steps of providing an etching priming reactant into a reaction chamber and providing a radical species generated by plasma into the reaction chamber. The etching cycle may include the step of removing excess reactant and / or reaction by-products from the reaction chamber if any are present. The removal may be performed as a purge step. In some embodiments, the etching cycle is repeated two or more times. In some embodiments, the etching cycle is repeated immediately after the previous cycle is completed, that is, when there are no additional process steps between two etching cycles.

[0089] Unless the present disclosure is limited by any particular theory, the etch priming reactant may be advantageous for controlling the etching process according to the present disclosure. In some embodiments, it may be possible to control the density of the etch priming reactant on the first surface by controlling the time the etch priming reactant exists in the reaction chamber, i.e., the pulse time of the etch priming reactant. Additionally, the chemical adsorption of the etch priming reactant onto the substrate surface may be controlled by the substrate temperature and, for example, by controlling the concentration of the etch priming reactant near the substrate through the use of a gas flow and a diluent gas. The density of the etch priming reactant on the substrate surface may be proportional to the etching rate and / or degree on the first surface. In some embodiments, the etch priming reactant may be deposited only substantially or only on the first surface of the substrate.

[0090] Additionally, the presence of etching priming reactants can make it possible, or at least help, to make the etching process self-limiting. Unless the present disclosure is limited by any particular theory, the etching priming reactants may be removed from the first surface by plasma exposure. Once the etching priming reactants are removed from the first surface by plasma exposure, the etching of the first surface may be stopped or slowed down. Accordingly, controlling the intensity of the plasma treatment as well as appropriately selecting the gas in which the plasma is generated may provide other methods for controlling the selective etching process according to the present disclosure.

[0091] In some embodiments, the etching cycle is included in the deposition process. In some embodiments, the etching cycle is included in the selective deposition process. Accordingly, the selective etching process according to the present disclosure may be used in combination with one or more selective and / or non-selective deposition processes to achieve selective deposition on a substrate.

[0092] The method according to the present disclosure may be used in a non-selective mode for etching a surface comprising an etchable material. Accordingly, in one embodiment, a method for etching a metal or metal oxide, such as silicon oxide, is disclosed. The method comprises the steps of providing a substrate comprising a metal or metal oxide into a reaction chamber, providing an etching priming reactant in gaseous form into the reaction chamber, and providing a reactive species generated from a plasma into the reaction chamber to etch the metal or metal oxide, wherein the etching priming reactant comprises a halogenated hydrocarbon. The etching process may be self-limiting. The etching cycle may be repeated to make it a periodic etching process. The foregoing with respect to the first surface applies to a metal or metal oxide surface of the non-selective method. Similarly, the foregoing with respect to the etching priming reactant applies to the non-selective method.

[0093] In one embodiment, an assembly for processing a substrate is disclosed. The assembly comprises: a reaction chamber configured and arranged to hold the substrate; an etching priming reactant source configured and arranged to contain and evaporate an etching priming reactant; a plasma generator for generating plasma; a plasma reactant source for providing gas to the plasma generator; and a reactant injection system configured and arranged to provide the etching priming reactant and plasma in gaseous form from the plasma generator into the reaction chamber.

[0094] The present disclosure is further explained by the following exemplary embodiments illustrated in the drawings. The examples presented herein are not intended to be actual views of any particular material, structure, or assembly, but are merely schematic representations used to describe embodiments of the present disclosure. It will be understood that elements in the drawings are illustrated in a simplified and clear manner and are not necessarily drawn to scale. For example, the dimensions of some elements in the drawings may be exaggerated compared to others to improve understanding of the illustrated embodiments of the present disclosure. Structures and elements illustrated in the drawings may include additional elements and details that may be omitted for clarity.

[0095] Panels a and b of FIG. 1 illustrate block diagrams of exemplary implementations of a selective etching method according to the present disclosure. The method (100) may be used to selectively etch a first material against a second material from a substrate. The etching method (100) may be used during the formation of a semiconductor structure or device.

[0096] During step (102), the substrate is provided within the reaction chamber of the substrate processing device. The reaction chamber may form part of the cluster tool. In some embodiments, the substrate processing device is a single wafer processing device. Alternatively, the device may be a batch processing device. Various steps of the method (100) may be performed within a single reaction chamber or within multiple reactor chambers, such as the reaction chamber of the cluster tool. In some embodiments, the method (100) is performed in a single reaction chamber of the cluster tool, but other preceding or subsequent manufacturing steps of the structure or device are performed in additional reaction chambers of the same cluster tool. The reaction chamber may be equipped with a heater to activate the reaction by raising the temperature of one or more of the substrate and / or reactants and / or other gases.

[0097] During step (102), the substrate may be brought to a desired temperature and pressure for the step (104) of providing an etching priming reactant to the reaction chamber and / or the step (106) of providing a reactive species to the reaction chamber. The temperature within the reaction chamber (e.g., the substrate or substrate support) may be, for example, about 20°C to about 120°C, or about 20°C to about 80°C, or about 20°C to about 60°C, or about 20°C to about 50°C. As another example, the temperature within the reaction chamber may be about 30°C to about 120°C, or about 30°C to about 80°C, or about 30°C to about 60°C, or about 30°C to about 55°C, or about 40°C to about 70°C, or about 40°C to about 80°C. Exemplary temperatures in the reaction chamber are 25°C, 35°C, 45°C, 50°C, 55°C, 70°C, 90°C, or 95°C.

[0098] The pressure inside the reaction chamber may be less than 760 Torr, for example, less than 100 Torr, less than 50 Torr, or less than 20 Torr, less than 5 Torr, less than 2 Torr, less than 1 Torr, or less than 0.1 Torr. In some embodiments, the pressure inside the reaction chamber is about 0.01 Torr to about 80 Torr, or about 0.01 Torr to about 50 Torr, or about 0.01 Torr to about 20 Torr, or about 0.01 Torr to about 10 Torr, or about 0.01 Torr to about 5 Torr, or about 0.01 Torr to about 1 Torr. Exemplary reaction chamber pressures include about 10 Torr, about 5 Torr, about 3 Torr, or about 1 Torr, or about 0.5 Torr or about 0.1 Torr. Different pressures may be used in different process steps. In some embodiments, the pressure is the same throughout the process.

[0099] In step (104), an etching priming reactant is provided within a reaction chamber containing a substrate. Unless the present disclosure is limited to any particular theory, the etching priming reactant may be chemically adsorbed onto a first surface of the substrate while the etching priming reactant is provided within the reaction chamber. In some embodiments, the etching priming reactant is not chemically adsorbed onto a second surface. In some embodiments, the etching priming reactant is chemically adsorbed onto the second surface to a lesser extent than on the first surface. The duration of providing the etching priming reactant within the reaction chamber (etching priming reactant pulse time) may be, for example, about 5 seconds to about 20 minutes. The duration of providing the etching priming reactant within the reaction chamber is selected based on the process, tool, and other factors. In some embodiments, the duration of providing the etching priming reactant within the reaction chamber is about 5 seconds to about 2 minutes, or about 5 seconds to about 90 seconds, or about 5 seconds to about 60 seconds. In some embodiments, the duration of providing the etching priming reactant in the reaction chamber is about 15 seconds to about 5 minutes, or about 15 seconds to about 3 minutes, or about 15 seconds to about 2 minutes, or about 10 seconds to about 90 seconds. In some embodiments, the duration of providing the etching priming reactant in the reaction chamber (etching priming reactant pulse time) may be longer than 5 seconds, longer than 10 seconds, longer than 30 seconds, or longer than 60 seconds. In some embodiments, the duration of providing the etching priming reactant in the reaction chamber (etching priming reactant pulse time) may be less than about 15 minutes, less than about 10 minutes, less than about 5 minutes, or less than about 3 minutes, or less than about 60 seconds, or less than about 30 seconds. Alternatively, the purge time after the etch priming reactant pulse is about 0.1 seconds to about 120 seconds, or about 0.1 seconds to about 60 seconds, or about 0.1 seconds to about 30 seconds, or about 0.1 seconds to about 10 seconds, or about 0.1 seconds to about 5 seconds, or about 0.The time may be 1 second to about 2 seconds, or about 0.1 second to about 1 second, or about 0.1 second to about 0.5 seconds. In some embodiments, the purge time after the etching priming reactant is less than 60 seconds, less than 30 seconds, less than 10 seconds, less than 4 seconds, less than 1 second, or less than 0.5 seconds.

[0100] In step (106), a reactive species generated from the plasma is introduced into the reaction chamber. The reactive species may react with the chemically adsorbed etching priming reactant or a derivative species thereof to form a species that etches the material of the first surface. The etching species may be generated locally to cause etching only in the area where the etching priming reactant is present, or substantially only to cause etching. Alternatively or additionally, the reactive species generated from the plasma may cause direct etching. In some embodiments, the etching priming reactant reacts with the reactive species to a lesser extent on the second surface than on the first surface. The duration of introducing the reactive species from the plasma into the reaction chamber (plasma pulse time) may be, for example, about 0.1 seconds to about 5 minutes, or about 0.1 seconds to about 3 minutes, or about 0.1 seconds to about 1 minute, or about 0.1 seconds to about 30 seconds, or about 0.1 seconds to about 10 seconds. In some embodiments, the plasma pulse time is about 1 second to about 5 minutes, or about 1 second to about 3 minutes, or about 1 second to about 60 seconds, or about 1 second to about 30 seconds. In some embodiments, the plasma pulse time is about 0.5 seconds, about 1 second, about 3 seconds, about 5 seconds, about 10 seconds, about 15 seconds, about 25 seconds, about 30 seconds, about 45 seconds, or about 60 seconds. In some embodiments, the duration of providing reactive species from the plasma into the reaction chamber is less than about 60 seconds, less than about 30 seconds, less than about 10 seconds, or less than about 5 seconds. Conversely, in some embodiments, a minimum duration for the plasma pulse may be defined. For example, the plasma pulse time may be greater than about 40 seconds, greater than about 25 seconds, greater than about 15 seconds, greater than about 8 seconds, greater than about 5 seconds, or greater than about 0.5 seconds.

[0101] In some embodiments, the etching priming reactant may be heated before being provided into the reaction chamber. In some embodiments, the etching priming reactant may be maintained at ambient temperature before being provided into the reaction chamber.

[0102] Steps (104 and 106) may form an etching cycle to etch the material of the first surface. In some embodiments, the two steps of selective etching according to the present disclosure, namely, providing an etching priming reactant and a reactive species generated from the plasma into the reaction chamber (steps 104 and 106), may be repeated (loop 108). Such embodiments include multiple etching cycles. The amount of material etched from the first surface may be controlled by adjusting the number of deposition cycles and / or parameters during etching. The etching cycle (loop 108) may be repeated until a desired amount of material is removed. For example, 1, 2, 3, 4, or 5 etching cycles may be performed. In some embodiments, about 10, about 20, about 50, or about 100 etching cycles may be performed. In some embodiments, the etching process according to the present disclosure is initiated by the step (104) of first providing an etching priming reactant into a reaction chamber, and then providing a reactive species generated from plasma into the reaction chamber (106). However, an embodiment may be considered in which the reactive species generated from plasma is first provided into the reaction chamber (106), and then the etching priming reactant is provided (104). For example, the reactive species may be used to clean or otherwise condition the substrate surface for etching.

[0103] The amount of material removed during one etching cycle depends on process conditions such as etching priming reactants, ion energy, and substrate temperature. In some embodiments, the material is removed from the first surface at a rate of about 0.3 Å / cycle to about 25 Å / cycle. In some embodiments, the etching rate of the material from the first surface may be, for example, about 2 Å / cycle to about 20 Å / cycle, whereas in some other embodiments, the etching rate may be, for example, about 3 Å / cycle to about 20 Å / cycle, or about 3 Å / cycle to about 15 Å / cycle. For example, the etching rate may be about 1 Å / cycle, or about 5 Å / cycle, or about 8 Å / cycle, or about 12 Å / cycle. Depending on the etching conditions, the number of etching cycles, etc., a variable depth of the material may be removed by etching. The desired etching depth achieved by the method according to the present disclosure can be selected based on the application of the problem.

[0104] The etching priming reactants and reactive species generated from the plasma may be provided into the reaction chamber in separate steps (104 and 106). Panel b of FIG. 1 illustrates an embodiment according to the present disclosure, in which steps (104 and 106) are separated by purging steps (105 and 107). In this embodiment, the etching cycle comprises one or more purging steps (105, 107). During the purging step, the etching priming reactants and / or reactive species generated from the plasma gas may be temporarily separated from each other by an inert gas, such as argon (Ar), nitrogen (N2), or helium (He) and / or vacuum pressure. Alternatively, the separation of the etching priming reactants and reactive species may be spatial.

[0105] Purge of the reaction chamber (105, 107) can prevent or mitigate gas-phase reactions between the etching priming reactants and reactive species generated from the plasma, and can improve process efficiency and specificity. If excess reactants and / or reaction byproducts and / or decomposition products are present, they can be removed from the substrate surface, for example, by purging the reaction chamber or moving the substrate, before the process continues. However, in some embodiments, the substrate may be moved to come into contact separately with the etching priming reactants and reactive species generated from the plasma. In some embodiments, because the reaction may be self-limiting, precise dosage control of the reactants and reactive species may not be required.

[0106] In some embodiments, the etching priming reactant comes into contact with the substrate surface in step (104), and the excess etching priming reactant is partially or substantially completely removed by an inert gas or vacuum in step (105), and the reactive species generated from the plasma comes into contact with the substrate surface containing the etching priming reactant. The etching priming reactant may be present only on the first surface of the substrate or substantially only on it. The etching priming reactant may come into contact with the substrate surface (104) in one or more pulses. That is, the pulsed etching of the etching priming reactant (104) may be repeated. The etching priming reactant on the substrate surface may react with the reactive species generated from the plasma to etch the material on the first surface of the substrate. Additionally, the plasma pulsed etching may be repeated to generate the reactive species in step (106). In some embodiments, the reactive species may be first provided to the reactor chamber (106). After that, the reaction chamber can be purged (105), and the etching priming reactant is supplied into the reaction chamber with one or more pulses (104).

[0107] The selective etching process according to the present disclosure may include additional pretreatment or posttreatment steps. For example, the substrate may be cleaned before the start of the process through a thermal, plasma, or chemical cleaning process. Any residual etching priming reactants, reaction byproducts, or decomposition residues may be removed from the reaction chamber after the etching process by a separate purge step or through thermal, chemical, or plasma cleaning.

[0108] FIG. 2 illustrates an exemplary method (200) for selectively etching material from a first surface (202) of a substrate onto a second surface (204) of the substrate. Panel a) illustrates a substrate (206) including a first surface (202) and a second surface (204). In the example of FIG. 2, the first surface (202) and the second surface (204) are located on a bulk substrate material (206). Additionally, although the two surfaces (202, 204) are depicted as being in a single plane, the two surfaces may be at different vertical levels or have a variable topology.

[0109] In panel b), an etching priming reactant (208) is deposited on the first surface (202). Panel c) indicates providing reactive species generated from the plasma into the reaction chamber. Thus, the reactive species come into contact with the substrate, and the presence of the etching priming reactant (208) on the first surface (202) will cause selective etching of the first surface (202) as shown in panel d). Although not shown in the schematic diagram of FIG. 2, some material from the second surface (204) may also be etched. However, the etching rate of the second surface (204) is lower than the etching rate of the first surface (202). The difference in etching rates between the first surface (202) and the second surface (204) depends on process parameters and the materials used. In some embodiments, the first surface (202) comprises silicon oxide, is essentially composed of, or is composed of, and the second surface (204) comprises silicon nitride, is essentially composed of, or is composed of.

[0110] In a non-limiting example, the silicon oxide surface may be selectively etched against the silicon nitride surface. The substrate temperature may be maintained at 50°C, while the reactant source may be maintained at ambient temperature. The pressure inside the reaction chamber may be 0.01 Torr to about 2.5 Torr during the process. The etching priming reactant may be provided inside the reaction chamber for about 30 seconds to about 5 minutes. The etching priming reactant may include perfluoro-octylsilane (POCS). The reaction chamber may be purged after the etching priming reactant is provided inside the reaction chamber. Then, an argon plasma may be provided inside the reaction chamber. The RF power used for plasma generation may be about 30 W to about 100 W, e.g., 50 W. The plasma may be maintained for about 30 seconds to about 2 minutes. However, if the plasma generation frequency is, for example, 13.56 MHz and the pressure is higher, the plasma treatment duration can be much shorter, such as from 0.1 seconds to 30 seconds. The reaction chamber can be purged after introducing reactive species into the reaction chamber. For example, about 1 nm of silicon oxide can be etched in each etching cycle.

[0111] FIG. 3 illustrates an exemplary embodiment of a substrate processing assembly (300) in schematic form according to the present disclosure. While the substrate processing assembly is schematically depicted, many components have been omitted for the sake of simplification of the example, and these components may include, for example, various valves, manifolds, purifiers, heaters, vessels, vents, and / or bypasses.

[0112] A substrate processing assembly (300) may include a reaction chamber (31), a plasma generator (32), a plasma reactant source (33A) for providing gas to generate radical species from the plasma, an inert gas source (33B), an etching priming reactant source (33C), a path (34) disposed between the remote plasma unit (32) and the reaction chamber (31), and gas lines (35A-35C) connecting the sources (33A-33C) to the reaction chamber (31). In an embodiment of FIG. 3, the plasma generator (32) is a remote plasma unit. In some embodiments, the substrate processing system may include a plurality of plasma generators (32) (e.g., one coupled to a hydrogen source to generate hydrogen radicals, and one coupled to a nitrogen source to generate nitrogen radicals). In an exemplary embodiment of FIG. 3, the substrate processing assembly (300) includes two gas sources (33A, 33B) in addition to the etching priming reactant source (33C). Since both gas sources (33A and 33B) are connected to the reaction chamber (31) via a plasma generator (32), they can be considered as plasma reactant sources, but depending on the process details, one of the gas lines (or if there are more gas sources) may bypass the plasma generator (32). The path (34) and gas lines (35A-35C), along with necessary valves, manifolds, etc., constitute a reactant injection system that provides etching priming reactants and plasma in the gas phase from the plasma generator into the reaction chamber.

[0113] FIG. 3 further illustrates an exhaust gas source (36). The exhaust source (36) may include one or more vacuum pumps. An embodiment of the substrate processing assembly further includes a controller (37). The controller (37) includes electronic circuits and software for selectively operating valves, manifolds, heaters, pumps, and other components included in the substrate processing assembly (300). These circuits and components operate to provide etching priming reactants and other gases, and to control temperatures, etc., thereby providing proper operation of the substrate processing assembly (300). The controller (37) may include modules, such as software or hardware components, that perform specific tasks. Modules may be configured to be mounted on an addressable storage medium of the control system and may be configured to execute one or more processes.

[0114] The substrate processing assembly of FIG. 3 may be part of a cluster tool comprising a plurality of reaction chambers. The reaction chambers (310) may be individual processing stations of a multi-station tool. In some embodiments, the substrate processing assembly includes hot-wall, cold-wall, or warm-wall type reaction chambers.

[0115] During the operation of the substrate processing assembly (300), a substrate, such as a semiconductor wafer (not shown), is transferred, for example, from a substrate handling system to a reaction chamber (31). Once the substrate(s) are transferred to the reaction chamber (31), one or more gases from gas sources (33A-33C), such as etching priming reactants, reactive species, and / or gases for generating purge gas, are introduced into the reaction chamber (31).

[0116] The exemplary embodiments of the foregoing disclosure do not limit the scope of the invention, because these embodiments are merely examples of embodiments of the invention, which are defined by the appended claims and their legal equivalents. Any equivalent embodiments are intended to be within the scope of the invention. In addition to what is shown and described herein, various modifications of the invention, such as alternative useful combinations of the described elements, 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.

Claims

Claim 1 A method for selectively etching a material from a first surface of a substrate onto a second surface of the substrate, the method comprising: providing a substrate including the first surface and the second surface to a reaction chamber; providing an etching priming reactant in gaseous form into the reaction chamber; and providing a reactive species generated from a plasma into the reaction chamber to selectively etch a material from the first surface, wherein the etching priming reactant is deposited on the first surface, the etching priming reactant comprises a halogenated hydrocarbon, the etching priming reactant comprises a head group and a tail group, and the head group comprises a third-row semimetal or nonmetal. Claim 2 In claim 1, the method wherein the selective etching process is a periodic etching process. Claim 3 A method according to claim 1 or 2, wherein the selective etching process is a self-limiting process. Claim 4 A method according to claim 1 or 2, wherein the etching priming reactant and the reactive species are provided alternately and sequentially within the reaction chamber. Claim 5 A method according to claim 1 or 2, wherein the reaction chamber is purged after providing an etching priming reactant and / or a reactive species within the reaction chamber. Claim 6 A method according to claim 1 or 2, wherein the first surface comprises oxygen. Claim 7 In claim 6, the method wherein the first surface comprises an oxide. Claim 8 A method according to claim 1 or 2, wherein the second surface comprises nitrogen. Claim 9 In claim 8, the method wherein the second surface comprises a nitride. Claim 10 In claim 8, the method wherein the second surface comprises nitrogen and hydrogen. Claim 11 A method according to claim 1 or 2, wherein the second surface does not contain oxygen. Claim 12 delete Claim 13 delete Claim 14 A method according to claim 1 or 2, wherein the third row semimetal or nonmetal is selected from the group consisting of silicon, phosphorus and sulfur. Claim 15 A method according to claim 1 or 2, wherein the head group comprises an oxygen atom connected to the rest of the molecule through a double bond. Claim 16 A method according to claim 1 or 2, wherein the head group comprises an amine group. Claim 17 A method according to claim 1 or 2, wherein the head device comprises a halogen atom attached to the third row nonmetal or semimetal. Claim 18 In claim 17, the above head device comprises a halosilane, in a method. Claim 19 A method according to claim 1 or 2, wherein the etching priming reactant comprises an aromatic hydrocarbon. Claim 20 A method according to claim 1 or 2, wherein the etching priming reactant forms a self-assembled monolayer on the first surface. Claim 21 A method for selectively etching a material from a first surface of a substrate onto a second surface of the substrate, wherein the method comprises an etching process including the step of forming an etching priming layer on the first surface using a halosilane compound including an aromatic hydrocarbon, wherein the aromatic hydrocarbon is halogenated. Claim 22 An assembly for processing a substrate, comprising: a reaction chamber configured and arranged to hold said substrate; an etching priming reactant source configured and arranged to contain and evaporate an etching priming reactant; a plasma generator for generating plasma; a plasma reactant source for providing gas to said plasma generator; and a reactant injection system configured and arranged to provide said etching priming reactant and plasma in a gaseous state from said plasma generator into said reaction chamber, wherein said etching priming reactant comprises a head unit and a tail unit, said head unit containing a third-row semimetal or nonmetal. Claim 23 In paragraph 22, the reaction chamber is an assembly configured and arranged to vapor-etch a semiconductor substrate, the reaction chamber being an etching chamber.

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