Anisotropic thermal etching of SiO2

Abstract

A method for etching features within a stack is provided. Multiple cycles are provided. A thermal etching step for etching features within a stack is provided within the cycle, the stack comprising at least one silicon oxide layer, and the thermal etching step includes supplying a thermal etching gas in a vapor phase comprising halogen-containing vapor or gas and a vapor catalyst, and supplying thermal energy to drive a reaction for etching features within the stack. A passivation step for depositing a passivation layer on the sidewalls of the features is provided within the cycle.

Description

[Background technology]

[0001] Cross-references to related applications This application claims priority under U.S. Patent Application No. 63 / 500,826, filed on 8 May 2023, which is incorporated herein by reference for all purposes.

[0002] When forming semiconductor devices, etching layers may be etched to form memory holes or lines or other semiconductor features. Some semiconductor devices can be formed, for example, by etching a single silicon dioxide (SiO2) layer to form capacitors in dynamic access random memory (DRAM). Other semiconductor devices can be formed by etching stacks of alternating silicon dioxide (oxide) and silicon nitride (nitride) bilayers (ONON) or alternating silicon dioxide and polysilicon (OPOP) bilayers. Such stacks can be used in memory applications and three-dimensional "not and" gates (3D NAND). These stacks tend to require etching of the dielectric at a relatively high aspect ratio (HAR). For high aspect ratio etching, desirable etching characteristics include high etching selectivity for masks (such as amorphous carbon masks), low sidewall etching in straight profiles, and high etching rate at the etch front. Some high aspect ratio etchings result in tapered features that are much wider at the top than at the bottom. Such features can increase device failure or limit device density, device performance, and device depth. Etching can also be used for drilling, shallow trench isolation, and carbon mask openings.

[0003] The background art provided herein is intended to provide a general overview of the background of this disclosure. The information contained herein, along with any manner of description that would not ordinarily be considered prior art at the time of filing, is not considered prior art to this disclosure, either explicitly or implicitly. [Overview of the project]

[0004] To address the aforementioned issues, a method for etching features within a stack is provided in accordance with the purposes of this disclosure. Multiple cycles are provided. A thermal etching step for etching features within a stack is provided within the cycle, the stack comprising at least one silicon oxide layer, and the thermal etching step includes supplying a thermal etching gas in a vapor phase comprising halogen-containing vapor or gas and a vapor catalyst, and supplying thermal energy to drive a reaction for etching features within the stack. A passivation step for depositing a passivation layer on the sidewalls of the features is provided within the cycle.

[0005] In another embodiment, a method for etching features within a stack is provided, comprising multiple cycles. Each cycle comprises the steps of providing plasma etching and providing thermal etching for etching features within a stack, wherein the stack comprises at least two layers, and at least one of the two layers is a silicon oxide layer. The thermal etching includes the step of supplying a thermal etching gas in a vapor phase comprising halogen-containing vapor or gas and a vapor catalyst. Thermal energy is supplied to drive the reaction for etching features within the stack.

[0006] In another embodiment, an apparatus for etching a substrate is provided. A reaction chamber is configured to provide a pressure of about 0.2 to 10 Torr within the reaction chamber. A substrate support is configured to support the substrate within the reaction chamber. At least one inlet introduces a gas mixture into the reaction chamber. A halogen vapor or gas source supplies halogen vapor or gas to at least one inlet. A vapor catalyst source supplies vapor catalyst to at least one inlet. At least one of a passivation gas source and an etching plasma gas source is connected to at least one inlet. A heater supplies thermal energy to the substrate. An outlet removes vapor from the reaction chamber. A controller is configured to provide a circulation process. Each cycle includes a thermal etching step and at least one of a passivation step and a plasma etching step.

[0007] The above-mentioned and other features of this disclosure will be described in detail in a detailed description with reference to the attached drawings. [Brief explanation of the drawing]

[0008] The attached drawings illustrate this disclosure for illustrative purposes only, not for limitation. In these attached drawings, similar components are denoted by the same reference numerals.

[0009] [Figure 1] High-level flowcharts of several embodiments.

[0010] [Figure 2A] A schematic cross-sectional view showing a stack processed according to several embodiments. [Figure 2B] A schematic cross-sectional view showing a stack processed according to several embodiments. [Figure 2C] A schematic cross-sectional view showing a stack processed according to several embodiments. [Figure 2D] A schematic cross-sectional view showing a stack processed according to several embodiments. [Figure 2E]A schematic cross-sectional view showing a stack processed according to several embodiments.

[0011] [Figure 3] High-level flowcharts of several embodiments.

[0012] [Figure 4A] A schematic cross-sectional view showing a stack processed according to several embodiments. [Figure 4B] A schematic cross-sectional view showing a stack processed according to several embodiments. [Figure 4C] A schematic cross-sectional view showing a stack processed according to several embodiments. [Figure 4D] A schematic cross-sectional view showing a stack processed according to several embodiments. [Figure 4E] A schematic cross-sectional view showing a stack processed according to several embodiments. [Figure 4F] A schematic cross-sectional view showing a stack processed according to several embodiments.

[0013] [Figure 5] A schematic diagram showing an etching chamber that may be used in several embodiments.

[0014] [Figure 6] A schematic diagram showing a computer system that can be used to implement several embodiments. [Modes for carrying out the invention]

[0015] The following description provides a detailed explanation of the disclosure with reference to several preferred embodiments illustrated in the accompanying drawings. The following description includes numerous specific details to facilitate a full understanding of the disclosure. However, as will be apparent to those skilled in the art, the disclosure can be implemented without some or all of these specific details. Furthermore, to avoid unnecessarily obscuring the disclosure, detailed descriptions of well-known processes and / or structures have been omitted.

[0016] Dry development of high aspect ratio contacts requires precise control of the sidewall taper angle. Various methods attempt to limit the difference in lateral critical dimension (CD) between the top and bottom of the etched structure. In the recent development of 3D NAND memory with thicker structures and an increasing number of ONON or OPOP bilayers, the requirement for precise control of the top and bottom shapes has become particularly important. If the taper (difference between the top and bottom CDs) increases, subsequent processes in device manufacturing are exposed to the risk of affecting device performance. In current technology, reactive ion etching of high aspect ratio structures relies on sidewall deposition to prevent lateral erosion of the CD. For high aspect ratio features, maintaining a delicate balance between etching and sidewall deposition is particularly difficult. As a result, dry development of high aspect ratios is limited to thinner structures and requires significantly more complex development processes to enable etching of thin stacks.

[0017] Thermal etching cycle with passivation Some embodiments described herein provide deeper, high-aspect-ratio features etched into a stack, with reduced tapering and bowing, such that the width of the feature near the top of the feature is approximately equal to the width of the feature near the bottom of the feature. For ease of understanding, Figure 1 shows a high-level flowchart that may be used in some embodiments. In some embodiments, the stack is placed in an etching chamber (step 104). Figure 2A is a schematic cross-sectional view of a stack 204 that may be processed according to some embodiments. The stack 204 may be formed on a substrate 208. The stack 204 is a silicon oxide (SiO2) layer 212 placed beneath a silicon nitride (SiN) mask 216 having a mask feature 220. In some embodiments, one or more layers may be present between the silicon oxide layer 212 and the substrate 208. In some embodiments, one or more layers may be present between the silicon oxide layer 212 and the SiN mask 216. In some embodiments, the mask feature 220 has a CD of less than 20 nanometers (nm). The silicon oxide layer includes a silicon oxide-based layer. A silicon oxide layer is a silicon oxide layer that may also contain one or more dopants. Similarly, a polysilicon layer includes a polysilicon layer having at least one dopant that forms a polysilicon layer. A silicon nitride layer includes a silicon nitride layer having at least one dopant that forms a silicon nitride layer.

[0018] A cyclic process (step 108) is provided for etching the stack. In some embodiments, the cyclic process (step 108) includes a thermal etching step (step 112), a passivation step (step 116), and a breakthrough step (step 120). In some embodiments, the cycle does not have a breakthrough step (step 120). In some embodiments, two or more of the processes are performed in situ within the same processing chamber.

[0019] Thermal etching In some embodiments, the thermal etching step (step 112) includes providing a thermal etching gas and providing thermal energy to drive a reaction in which the thermal etching gas etches the stack 204. In some embodiments, the thermal etching gas modifies a portion of the stack. In some embodiments, the thermal etching step is a non-plasma process. In some embodiments, the thermal etching gas includes a halogen-containing vapor and a vapor catalyst, where the vapor catalyst includes an organic solvent and / or water, an additive, and a carrier gas. In some embodiments, the thermal etching gas is provided cyclically by providing a step of providing the halogen-containing gas and a step of sequentially providing the vapor and vapor catalyst. In some embodiments, the halogen-containing gas and the vapor containing the catalyst are provided simultaneously during the thermal etching step. In some embodiments, the halogen-containing gas is hydrogen fluoride (HF) gas. The terms “vapor phase” and “gas phase” are used interchangeably in this disclosure. The halogen-containing vapor and vapor catalyst form a gas mixture. The additive may have specific properties or specific compositions, as will be detailed later. The substrate may be etched at low pressure using thermal energy, for example, in a vacuum reaction chamber. In such cases, the substrate is not exposed to the plasma during the etching reaction. The substrate can be selectively etched such that one or more materials are targeted for removal, while other materials are etched to a lower degree. In some embodiments, silicon oxide is the material targeted for selective removal. In some embodiments, thermal energy is used to drive an endothermic reaction in a thermal etching gas that selectively etches the first material in the stack relative to the second material in the stack. One advantage of the disclosed technology is that a high degree of selectivity is achieved during etching. Another advantage of the disclosed technology is that it provides extremely precise control of the etching rate and the amount of material removed, in particular, compared to other thermally driven etching processes.The thermal etching process is described in International Publication No. 2021 / 202411A1, “Selective precision etching of semiconductor materials,” filed on 7 October 2021, which is incorporated by reference for all purposes.

[0020] Examples of organic solvents, transport gases, and additives in some embodiments are as follows:

[0021] Organic solvents alcohol: In certain examples, the organic solvent may be an alcohol. The alcohol has the chemical formula XC(R) n It can be an alcohol containing (OH)-Y, where, n is 1, Each X and Y is hydrogen, -[C(R 1 )2] m -C(R 2 )3, or independently selected from OH, where each R 1 and R 2 R is independently selected from hydrogen, hydroxyl, aliphatic, haloaliphatic, haloheteroliphatic, heteroaliphatic, aromatic, aliphatic-aromatic, heteroaliphatic-aromatic, or any combination thereof, m is an integer from 0 to 10, and each R is independently selected from hydrogen, hydroxyl, aliphatic, haloaliphatic, haloheteroliphatic, heteroaliphatic, aromatic, aliphatic-aromatic, heteroaliphatic-aromatic, or any combination thereof.

[0022] In some embodiments, each R, R 1 , and, R 2is independently selected from alkyl, alkenyl, alkynyl, heteroalkyl, heteroalkenyl, heteroalkynyl, haloalkyl, haloalkenyl, haloalkynyl, haloheteroalkyl, haloheteroalkenyl, haloheteroalkynyl, aryl, heterocyclyl, heteroaryl, alkyl-aryl, alkenyl-aryl, alkynyl-aryl, alkyl-heterocyclyl, alkenyl-heterocyclyl, alkynyl-heterocyclyl, alkyl-heteroaryl, alkenyl-heteroaryl, alkynyl-heteroaryl, heteroalkyl-aryl, heteroalkenyl-aryl, heteroalkynyl-aryl, heteroalkyl-heterocyclyl, heteroalkenyl-heterocyclyl, heteroalkynyl-heterocyclyl, heteroalkyl-heteroaryl, heteroalkenyl-heteroaryl, heteroalkynyl-heteroaryl, or any combination thereof. In certain disclosed embodiments, the alcohol may further be substituted with one or more substituents such as alkoxyl, amide, amine, thioether, thiol, acyloxy, silyl, cycloaliphatic, aryl, aldehyde, ketone, ester, carboxylic acid, acyl, halogenated acyl, cyano, halogen, sulfonate, nitro, nitroso, quaternary amine, pyridinyl (or pyridinyl where the nitrogen atom is functionalized with an aliphatic or aryl group), halogenated alkyl, or any combination thereof.

[0023] In other embodiments, at least one of X or Y = -[C(R 1 )2] m -C(R 2 )3￢ and when R is hydrogen and m is 1, the alcohol can be a C3 alcohol. For example, when at least one R 1 and one R 2 are absent, the C3 alcohol can be a C3 alkenol (e.g., allyl alcohol). In another example, when R and one R 2 can together form a ring (such as a cycloaliphatic), the C3 alcohol can be cyclopropanol or 2-cyclopropenol.

[0024] In yet another embodiment, at least one of X or Y = -[C(R 1 )2] m -C(R 2 If R is 3¬ or R is hydrogen and m is 2, then the alcohol can be a C4 alcohol. For example, if at least one R 1 and one R 2 If not present, the C4 alcohol can be a C4 alkenol (e.g., 2-buten-1-ol or 3-buten-1-ol). In another example, R and one R 2 If both X and Y can form a ring (such as a cycloaliphatic ring), the C4 alcohol can be a C4-cyclic alcohol (e.g., cyclobutanol or cyclopropylmethanol). In yet another example, if neither X nor Y is an OH group, the C4 alcohol can be a C4-branched alcohol (e.g., 2-butanol, isobutanol, or tert-butanol).

[0025] In some examples, X = OH and Y = -[C(R 1 )2]mC(R 2 If )3¬, the alcohol can be a diol. Another example is at least one of X or Y = -[C(R 1 )2]mC(R 2 )3 and at least one R 1 =OH or one R 2 If the relationship is =OH, or R=OH, then the alcohol can be a diol. Examples of diols include, but are not limited to, 1,4-butanediol and propylene-1,3-diol.

[0026] In other examples, if X=Y=OH, the alcohol can be a triol. In yet another example, if X=R=OH, the alcohol can be a triol. In some examples, at least one of X or Y is -[C(R 1 )2] m -C(R 2 )3 and one R1 and at least one R 2 If is OH, the alcohol can be a triol. In other examples, R=OH and X=-[C(R 1 )2] m -C(R 2 )3, and one R 1 and at least one R 2 When the OH group is present, the alcohol can be a triol. Examples of triols include, but are not limited to, glycerol or its glycerol derivatives.

[0027] In certain embodiments, if R = cycloheteroaliphatic, heterocyclyl, heteroaryl, alkyl-heterocyclyl, alkenyl-heterocyclyl, alkynyl-heterocyclyl, heteroalkyl-heterocyclyl, heteroalkenyl-heterocyclyl, or heteroalkynyl-heterocyclyl, the alcohol may be a heterocyclyl alcohol (e.g., an optionally substituted heterocyclyl substituted with one or more hydroxyl groups, such as furfuryl alcohol). In other embodiments, at least one of X or Y is [C(R 1 )2] m -C(R 2 )3 and one R 1 and at least one R 2 However, if the alcohol is a cycloheteroliphatic, heterocyclyl, heteroaryl, alkyl-heterocyclyl, alkenyl-heterocyclyl, alkynyl-heterocyclyl, heteroalkyl-heterocyclyl, heteroalkenyl-heterocyclyl, or heteroalkynyl-heterocyclyl, then the alcohol may be a heterocyclyl alcohol.

[0028] In various embodiments, the alcohol may have 1 to 10 carbon atoms. The alcohol may be a primary alcohol, a secondary alcohol, or a tertiary alcohol. In some cases, the alcohol may be selected from the group consisting of methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, t-butanol, 1-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 1-nonanol, 1-decanol, and combinations thereof.

[0029] Laboratory solvent: In these or other cases, the organic solvent may include experimental solvents such as acetonitrile, dichloromethane, carbon tetrachloride, or combinations thereof.

[0030] Ketones: In some embodiments, the organic solvent may be a ketone.

[0031] Organic solvents have the chemical formula X-[C(O)] n The ketone may have -Y, where n is an integer between 1 and 2. Each X and Y is -C(R 1 )3, -R 2 , or [C(R 3 )2] m -C(O)-R 4 They may be selected independently from each R 1 , R 2 , R 3 , and, R 4 These may be independently selected from hydrogen, hydroxyl, aliphatic, haloaliphatic, haloheteroliphatic, heteroaliphatic, aromatic, aliphatic-aromatic, heteroaliphatic-aromatic, or any combination thereof. R 3 and R 4 X and Y can optionally form cycloaliphatic or cycloheteraliphatic groups with their respective bonding atoms, m is an integer between 0 and 10.

[0032] In some embodiments, each R 1 , R 2 , R 3 , and, R 4 These are, independently, alkyl, alkenyl, alkynyl, heteroalkyl, heteroalkenyl, heteroalkynyl, haloalkyl, haloalkenyl, haloalkynyl, haloheteroalkyl, haloheteroalkenyl, haloheteroalkynyl, aryl, heterocyclyl, heteroaryl, alkyl-aryl, alkenyl-aryl, alkynyl-aryl, alkyl-heterocyclyl, alkenyl-heterocyclyl, alkynyl-heterocyclyl, alkyl-heteroaryl, alkenyl-heteroaryl, alkynyl-heteroaryl, heteroalkyl-aryl, heteroalkenyl-aryl, heteroalkynyl-aryl, heteroalkyl-heterocyclyl, heteroalkenyl-heterocyclyl, heteroalkynyl-heterocyclyl, heteroalkyl-heteroaryl, heteroalkenyl-heteroaryl, heteroalkynyl-heteroaryl, or any combination thereof. In certain disclosed embodiments, the organic solvent may further be substituted with one or more substituents, such as aldehydes (-C(O)H), oxo (=O), alkoxy, amide, amine, hydroxyl, thioether, thiol, acyloxy, silyl, cycloaliphatic, aryl, aldehyde, ketone, ester, carboxylic acid, acyl, acyl halogen, cyano, halogen, sulfonate, nitro, nitroso, quaternary amine, pyridinyl (or pyridinyl in which the nitrogen atom is functionalized with an aliphatic or aryl group), alkyl halogen, or any combination thereof. An example of a ketone is acetone.

[0033] In some embodiments, when X and Y, together with their respective bonding atoms, form a cycloaliphatic or cycloheteraliphatic system, the organic solvent can be a cyclic ketone. Examples of cyclic ketones include cyclohexanone, cyclopentanone, and the like.

[0034] In other embodiments, at least one of X or Y = [C(R 3 )2] m -C(O)-R 4 In this case, the organic solvent can be a diketone. Examples of diketones include diacetyl, 2,3-pentanedione, 2,3-hexanedione, 3,4-hexanedione, acetylacetone, acetonylacetone, and their halogenated forms (such as hexafluoroacetylacetone).

[0035] In a further embodiment, at least one of X or Y = [C(R 3 )2] m -C(O)-R 4 If X and Y, together with their respective bonding atoms, form a cycloaliphatic or cycloheteroliphatic system, then the organic solvent may be a cyclic diketone. Cyclic diketones include dimedone, 1,3-cyclohexanedione, and the like.

[0036] In some cases, when X = -CH3, the organic solvent is Y = -C(R 1 ) may have 3, where at least one R 1 C 2-10 These are hydroxyl, aliphatic, haloaliphatic, haloheteroaliphatic, heteroaliphatic, aromatic, aliphatic-aromatic, heteroaliphatic-aromatic, or any combination thereof. Examples of materials may include methyl propyl ketone, methyl butyl ketone, hydroxyacetone, etc.

[0037] In another example, if X = -CH3, then the organic solvent is Y = -R 2 It may have, where at least one R 2 C2 alkenyl, C 3-10 These can be aliphatic, haloaliphatic, haloheteroaliphatic, heteroaliphatic, aromatic, aliphatic-aromatic, heteroaliphatic-aromatic, or any combination thereof. Examples of materials may include methyl vinyl ketone, methyl propyl ketone, methyl butyl ketone, etc.

[0038] In further examples, the organic solvent can be an aromatic ketone if at least one X or Y is aromatic, aliphatic-aromatic, or heteroaliphatic-aromatic. Examples of materials include acetophenone, benzophenone, benzylacetone, 1,3-diphenylacetone, cyclopentylphenyl ketone, and others.

[0039] In certain embodiments, the organic solvent may be selected from acetone and acetophenone. One or more further ketones and / or other organic solvents described herein may be provided.

[0040] Alkan: In some embodiments, the organic solvent may be an alkane. In certain embodiments, the alkane is a compound with the general chemical formula C n H 2n+2 The alkane may be an acyclic branched or unbranched hydrocarbon having [a specific characteristic]. Examples of acyclic alkanes include, but are not limited to, pentane, hexane, octane, and combinations thereof. In certain other embodiments, the alkane may be a cyclic hydrocarbon. Examples of cyclic hydrocarbons include, but are not limited to, cyclopentane, cyclohexane, and combinations thereof.

[0041] Aromatic solvents: In some embodiments, the organic solvent may be an aromatic solvent. As used herein, “aromatic” means, unless otherwise specified, a cyclic conjugated group or moiety of 5 to 15 ring atoms having a single ring (e.g., phenyl) or multiple fused rings (e.g., naphthyl, indolyl, pyrazolopyridinyl) in which at least one ring is aromatic, i.e., at least one ring and optionally multiple fused rings have a continuous delocalized π-electron system. Typically, the number of out-of-plane π-electrons corresponds to Hückel's rule (4n+2). The attachment point to the parent structure typically passes through the aromatic moiety of the fused ring system. In some cases, the aromatic solvent may be selected from toluene and benzene.

[0042] Ether: In some embodiments, the organic solvent may be an ether having the chemical formula X-O-Y or X-O-[C(R)2] n -O-Y, where n is an integer from 1 to 4, each X and Y is independently selected from -[C(R 1 )2] m -C(R 2 )3 or -R 3 or -[C(R 4 )2] p -O-[C(R 5 )2] m -C(R 6 )3, where each of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , and each R is independently selected from hydrogen, hydroxyl, aliphatic, haloaliphatic, haloheteroaliphatic, heteroaliphatic, aromatic, aliphatic-aromatic, heteroaliphatic-aromatic, or any combination thereof, where m is an integer from 0 to 10 and p is an integer from 1 to 10, X and Y, together with the atoms to which they are attached, may optionally form a cycloheteroaliphatic group.

[0043] In some embodiments, each R, R 1 , R 2 , R 3 , R 4 , R 5 , and R [[ID=5a]] 6These are independently selected from alkyl, alkenyl, alkynyl, heteroalkyl, heteroalkenyl, heteroalkynyl, haloalkyl, haloalkenyl, haloalkynyl, haloheteroalkyl, haloheteroalkenyl, haloheteroalkynyl, aryl, heterocyclyl, heteroaryl, alkyl-aryl, alkenyl-aryl, alkynyl-aryl, alkyl-heterocyclyl, alkenyl-heterocyclyl, alkynyl-heterocyclyl, alkyl-heteroaryl, alkenyl-heteroaryl, alkynyl-heteroaryl, heteroalkyl-aryl, heteroalkenyl-aryl, heteroalkynyl-aryl, heteroalkyl-heterocyclyl, heteroalkenyl-heterocyclyl, heteroalkynyl-heterocyclyl, heteroalkyl-heteroaryl, heteroalkenyl-heteroaryl, heteroalkynyl-heteroaryl, or any combination thereof. In certain disclosed embodiments, the ether may be further substituted with one or more substituents, such as alkoxyl, amide, amine, thioether, thiol, acyloxy, silyl, cycloaliphatic, aryl, aldehyde, ketone, ester, carboxylic acid, acyl, acyl halogen, cyano, halogen, sulfonate, nitro, nitroso, quaternary amine, pyridinyl (or pyridinyl in which the nitrogen atom is functionalized with an aliphatic or aryl group), alkyl halogen, or any combination thereof.

[0044] In some embodiments, when X and Y, together with their respective bonding atoms, form a cycloheteroliphatic group, the organic solvent is a cyclic ether such as an acetal, dioxane, or dioxolane. In some embodiments, when n=1 and each R=H, X and Y together form a 6-membered, 7-membered, 8-membered, 9-membered, or 10-membered ring. Examples of ethers include, but are not limited to, 1,3-dioxolane or its derivatives. In other embodiments, when n=2 and each R=H, X and Y form a 7-membered, 8-membered, 9-membered, or 10-membered ring. Examples of ethers include, but are not limited to, 1,4-dioxane or its derivatives. In yet another embodiment, when n=1 or n=2, R is aliphatic, haloaliphatic, haloheteroliphatic, heteroaliphatic, aromatic, aliphatic-aromatic, heteroaliphatic-aromatic, or any combination thereof. Examples of cyclic ethers include tetrahydrofuran, 2-methyltetrahydrofuran, and 2-methyl-1,3-dioxolane.

[0045] In other embodiments, if at least one of X or Y is aromatic, the organic solvent may be an aromatic ether. Examples of aromatic ethers include anisole, diphenyl ether, and the like.

[0046] In some embodiments, if at least one of X or Y is cycloaliphatic, the organic solvent can be a cycloalkyl ether. Examples of cycloalkyl ethers include cyclopentyl methyl ether, cyclohexyl methyl ether, and the like.

[0047] In another embodiment, at least one of X or Y = -[C(R 4 )2-O] p -C(R 6)When it is 3, the organic solvent can be a glycol ether. Examples of glycol ethers include diethylene glycol diethyl ether, dipropylene glycol dimethyl ether, poly(ethylene glycol) dimethyl ether, etc., including methyl, ethyl, propyl, and butyl monoethers and diethers of ethylene glycol.

[0048] Nitrile: In some cases, the organic solvent is a nitrile having the chemical formula R-C≡N, where R is aliphatic, haloaliphatic, haloheteroaliphatic, heteroaliphatic, aromatic, aliphatic-aromatic, or heteroaliphatic-aromatic.

[0049] In certain embodiments, R can be optionally substituted with a hydroxyl group (e.g., in one example, R can be CH3-CH(OH)-CH 2- and the organic solvent can be CH3-CH(OH)-CH2-CN).

[0050] An example of the nitrile is acetonitrile as described above.

[0051] In some embodiments, the organic solvent can include two or more of the organic solvents or types of organic solvents described herein. In some embodiments, water may be provided instead of or in addition to the organic solvent.

[0052] Conveying gas The carrier gas can be an inert gas. In some cases, the carrier gas is a noble gas. In certain embodiments, the carrier gas can be selected from the group consisting of N2, He, Ne, Ar, Kr, and Xe. In some such embodiments, the carrier gas can be selected from the group consisting of N2, He, and Ar.

[0053] additives The additive may be selected from many different types of additives. For example, in some cases the additive may be a heterocyclic compound, a heterocyclic aromatic compound, a halogen-substituted heterocyclic aromatic compound, a heterocyclic aliphatic compound, an amine, a fluoroamine, an amino acid, an organophosphorus compound, an oxidizing agent, a bifluoride source, an ammonia, an aldehyde, a carbene, or an organic acid. In some cases two or more additives may be used. In some embodiments the additive may be a boron-containing Lewis acid or Lewis adduct. Boron trifluoride (BF3) is used in the acid-base adduct BF4. - This is an example of a Lewis acid that forms a reaction. In some cases, the additive may belong to two or more of the categories listed above. In various embodiments, the additive serves to accelerate the reaction rate and increase the reaction selectivity.

[0054] Heterocyclic aromatic compounds: In certain embodiments, the additive is a heterocyclic aromatic compound. The term "aromatic" is defined above. A heterocyclic aromatic compound is an aromatic compound containing a 5, 6, or 7-membered ring unless otherwise specified, and containing 1, 2, 3, or 4 non-carbon heteroatoms (e.g., independently selected from the group consisting of nitrogen, oxygen, phosphorus, sulfur, or halogens). Examples of heterocyclic aromatic compounds that may be used include, but are not limited to, picoline, pyridine, pyrrole, imidazole, thiophene, N-methylimidazole, N-methylpyrrolidone, benzimidazole, 2,2-bipyridine, dipicolinic acid, 2,6-lutidine, 4-N,N-dimethylaminopyridine, and azulene. In some cases, the heterocyclic aromatic compound may be methylated. In some cases, the heterocyclic aromatic compound may follow Hückel's 4n+2 rule. In some cases, the additive is a halogen-substituted aromatic compound. Halogen-substituted aromatic compounds are aromatic compounds that contain at least one halogen bonded to an aromatic ring. As used herein, halogen or halo refers to F, Cl, Br, or I. Examples of halogen-substituted aromatic compounds include, but are not limited to, 4-bromopyridine, chlorobenzene, 4-chlorotoluene, fluorobenzene, and others.

[0055] Heterocyclic aliphatic compounds: In some embodiments, the additive is a heterocyclic aliphatic compound. As used herein, “aliphatic” refers to a compound with at least one carbon atom and 50 carbon atoms (C 1-50 )(For example, 1 to 25 carbon atoms (C 1-25 ), or 1 to 10 carbon atoms (C 1-10This refers to hydrocarbon groups having (such as) alkanes (or alkyls), alkenes (or alkenyls), alkynes (or alkynyls), their cyclic forms, as well as their linear and branched arrangements, and all stereoisomers and positional isomers. Heterocyclic aliphatic compounds are aliphatic compounds containing one, two, three, or four noncarbon heteroatoms (e.g., independently selected from the group consisting of nitrogen, oxygen, phosphorus, sulfur, or halogens), and unless otherwise specified, they contain a 5, 6, or 7-membered ring. Examples of heterocyclic aliphatic compounds include pyrrolidines and piperidines.

[0056] Amine: In some embodiments, the additive is of the chemical formula NR 1 R 2 R 3 It is an amine having, and here, R 1 , R 2 , and, R 3 Each of these is independently selected from hydrogen, hydroxyl, aliphatic, haloaliphatic, haloheteroliphatic, heteroaliphatic, aromatic, aliphatic-aromatic, heteroaliphatic-aromatic, or any combination thereof. R 1 and R 2 It can selectively form cycloheteraliphatic groups with each of the atoms it bonds to, R 1 , R 2 , and, R 3 It can selectively form cycloheteraliphatic groups with each of the atoms it bonds to.

[0057] In some embodiments, R 1 , R 2 , and, R 3Each of these is independently selected from alkyl, alkenyl, alkynyl, heteroalkyl, heteroalkenyl, heteroalkynyl, haloalkyl, haloalkenyl, haloalkynyl, haloheteroalkyl, haloheteroalkenyl, haloheteroalkynyl, aryl, heterocyclyl, heteroaryl, alkyl-aryl, alkenyl-aryl, alkynyl-aryl, alkyl-heterocyclyl, alkenyl-heterocyclyl, alkynyl-heterocyclyl, alkyl-heteroaryl, alkenyl-heteroaryl, alkynyl-heteroaryl, heteroalkyl-aryl, heteroalkenyl-aryl, heteroalkynyl-aryl, heteroalkyl-heterocyclyl, heteroalkenyl-heterocyclyl, heteroalkynyl-heterocyclyl, heteroalkyl-heteroaryl, heteroalkenyl-heteroaryl, heteroalkynyl-heteroaryl, or any combination thereof. In certain disclosed embodiments, the amine may further be substituted with one or more substituents, such as alkoxyl, amide, amine, hydroxyl, thioether, thiol, acyloxy, silyl, cycloaliphatic, aryl, aldehyde, ketone, ester, carboxylic acid, acyl, acyl halogen, cyano, halogen, sulfonate, nitro, nitroso, quaternary amine, pyridinyl (or pyridinyl in which the nitrogen atom is functionalized with an aliphatic or aryl group), alkyl halogen, or any combination thereof.

[0058] In some embodiments, R 1 , R 2 , and, R 3 If at least one of the elements is aliphatic, haloaliphatic, haloheteroliphatic, or heteroaliphatic, the additive is an alkylamine. Alkylamines may include dialkylamines, trialkylamines, and their derivatives. Examples of alkylamines include dimethylisopropylamine, N-ethyldiisopropylamine, trimethylamine, dimethylamine, methylamine, triethylamine, t-butylamine, and the like.

[0059] In some embodiments, R1 , R 2 , and, R 3 If at least one of them contains hydroxyl, the additive is an alcoholamine. In one example, R 1 , R 2 , and, R 3 At least one of these groups is an aliphatic group substituted with one or more hydroxyls. Examples of alcoholamines include 2-(dimethylamino)ethanol, 2-(diethylamino)ethanol, 2-(dipropylamino)ethanol, 2-(dibutylamino)ethanol, N-ethyldiethanolamine, N-tertbutyldiethanolamine, and the like.

[0060] In some embodiments, R 1 and R 2 However, if the additive forms a cycloheteraliphatic group with each of the atoms it bonds to, the additive can be a cyclic amine. Examples of cyclic amines include piperidine, N-alkylpiperidine (e.g., N-methylpiperidine, N-propylpiperidine, etc.), pyrrolidine, N-alkylpyrrolidine (e.g., N-methylpyrrolidine, N-propylpyrrolidine, etc.), morpholine, N-alkylmorpholine (e.g., N-methylmorpholine, N-propylmorpholine, etc.), piperazine, N-alkylpiperazine, N,N-dialkylpiperazine (e.g., 1,4-dimethylpiperazine), and the like.

[0061] In some embodiments, R 1 , R 2 , and, R 3 If at least one of them contains an aromatic compound, the additive is an aromatic amine. In some embodiments, R 1 , R 2 , and, R 3 At least one of these is aromatic, aliphatic-aromatic, or heteroaliphatic-aromatic. In other embodiments, R 1 and R 2 Both contain aromatic compounds. In further embodiments, R 1 , R 2 , and, R 3These atoms, along with the atoms they bond to, form aromatic cycloheteraliphatic groups. Examples of aromatic amines include aniline, histamine, pyrrole, pyridine, imidazole, pyrimidine, and their derivatives.

[0062] In some embodiments, the additives may include amines selected from methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, isopropylamine, 1,2-ethylenediamine, aniline (and aniline derivatives such as N,N-dimethylaniline), N-ethyldiisopropylamine, tert-butylamine, and combinations thereof.

[0063] In some embodiments, the additive may include a fluoramine, which is an amine having one or more fluorine substituents. Examples of fluoroamines that may be used include, but are not limited to, 4-trifluoromethylaniline.

[0064] In some embodiments, the additive is of the chemical formula R 1 NC (NR) 2 )-NR 3 It may be a nitrogen analog of carbonic acid having [a certain property]. Examples of additives include, but are not limited to, guanidine or its derivatives.

[0065] In some embodiments, the additive may be a relatively low molecular weight amine, for example, having a molecular weight of less than 200 g / mol or less than 100 g / mol in certain embodiments. Higher molecular weight amines, such as those having long chains and / or heterocyclic compounds with aromatic rings, may be used in some embodiments.

[0066] amino acid: In some embodiments, the additive may include an amino acid. The amino acid may have the chemical formula R-CH(NR'2)-COOH, where, Each R and R' is hydroxyl, aliphatic, haloaliphatic, haloheteroliphatic, heteroaliphatic, aromatic, aliphatic-aromatic, heteroaliphatic-aromatic, or any combination thereof.

[0067] Examples of amino acids that can be used include, but are not limited to, histidine, alanine, and their derivatives.

[0068] Organophosphorus compounds: In some embodiments, the additive may include an organophosphorus compound. The organophosphorus compound may be a phosphate ester, phosphate amide, phosphonic acid, phosphinic acid, phosphonate, phosphinate, phosphine oxide, phosphine imide, or phosphonium salt. Examples of organophosphorus compounds include phosphonic acid and trialkyl phosphate. In some cases, the organophosphorus compound is a phosphazene. A phosphazene is an organophosphorus compound containing phosphorus(V) having a double bond between P and N. A phosphazene may have the chemical formula RN=P(NR2)3 (where each of R and R2 is independently selected from hydroxyl, aliphatic, haloaliphatic, haloheteroliphatic, heteroaliphatic, aromatic, aliphatic-aromatic, heteroaliphatic-aromatic, or any combination thereof). In some cases, a phosphazene has the chemical formula [X2PN] n (where X is a halogen compound, alkoxide, or amide) may be present. Other types of phosphazenes may be used as needed.

[0069] Oxidizing agent: In some embodiments, the additive includes an oxidizing agent. As used herein, an oxidizing agent is a material that has the ability to oxidize another substance (for example, by accepting electrons from another substance). Examples of oxidizing agents that may be used include, but are not limited to, hydrogen peroxide, sodium hypochlorite, and tetramethylammonium hydroxide.

[0070] Bifluoride source: In some embodiments, the additive includes a bifluoride source. The bifluoride source is bifluoride (HF2 - The material contains or produces ) . Examples of bifluoride sources that can be used include, but are not limited to, ammonium fluoride, aqueous hydrogen fluoride solutions, hydrogen fluoride gas, buffered oxide etching mixtures (e.g., mixtures of hydrogen fluoride and a buffer such as ammonium fluoride), and pyridine hydrogen fluoride. In some embodiments, the bifluoride source (and / or one or more of the other additives listed herein) is supplied to the reaction chamber before or after HF2 - It can react to form [something].

[0071] aldehyde: In some embodiments, the additive comprises an aldehyde having the chemical formula X-[C(O)]-H, where, X is hydrogen, -R 1 , -C(R 2 )3, or -[C(R 3 )2] m -C(O)H can be selected, R 1 , R 2 , and, R 3 m is independently selected from hydrogen, aliphatic, haloaliphatic, haloheteroliphatic, heteroaliphatic, aromatic, aliphatic-aromatic, heteroaliphatic-aromatic, or any combination thereof, and m is an integer between 0 and 10.

[0072] In some embodiments, R 1 , R 2 , and, R 3Each of these is independently alkyl, alkenyl, alkynyl, heteroalkyl, heteroalkenyl, heteroalkynyl, haloalkyl, haloalkenyl, haloalkynyl, haloheteroalkyl, haloheteroalkenyl, haloheteroalkynyl, aryl, heterocyclyl, heteroaryl, alkyl-aryl, alkenyl-aryl, alkynyl-aryl, alkyl-heterocyclyl, alkenyl-heterocyclyl, alkynyl-heterocyclyl, alkyl-heteroaryl, alkenyl-heteroaryl, alkynyl-heteroaryl, heteroalkyl-aryl, heteroalkenyl-aryl, heteroalkynyl-aryl, heteroalkyl-heterocyclyl, heteroalkenyl-heterocyclyl, heteroalkynyl-heterocyclyl, heteroalkyl-heteroaryl, heteroalkenyl-heteroaryl, heteroalkynyl-heteroaryl, or any combination thereof. In certain disclosed embodiments, the aldehyde or ketone may further be substituted with one or more substituents, such as aldehyde (-C(O)H), oxo (=O), alkoxy, amide, amine, hydroxyl, thioether, thiol, acyloxy, silyl, cycloaliphatic, aryl, aldehyde, ketone, ester, carboxylic acid, acyl, acyl halogen, cyano, halogen, sulfonate, nitro, nitroso, quaternary amine, pyridinyl (or pyridinyl in which the nitrogen atom is functionalized with an aliphatic or aryl group), alkyl halogen, or any combination thereof.

[0073] In some embodiments, when X = aromatic, the additive may be an aromatic aldehyde. Examples of aromatic aldehydes include benzaldehyde, 1-naphthaldehyde, phthalaldehyde, and the like.

[0074] In other embodiments, when X = aliphatic, the additive may be an aliphatic aldehyde. Examples of aliphatic aldehydes include acetaldehyde, propionaldehyde, butyraldehyde, isovalerylaldehyde, and the like.

[0075] In yet another embodiment, X = -[C(R3 )2] m If the additive is -C(O)H and m is between 1 and 10, or if it is an aliphatic or heteroaliphatic compound substituted with X=-C(O)H, then the additive may be a dialdehyde. Examples of dialdehydes include glyoxal, phthalaldehyde, glutaraldehyde, malondialdehyde, succinaldehyde, and the like.

[0076] In some examples, the aldehyde used as an additive may be selected from the group consisting of acrolein, acetaldehyde, formaldehyde, benzaldehyde, propionaldehyde, butyraldehyde, cinnamaldehyde, vanillin, and tolualdehyde. In these and other cases, the aldehyde used as an additive may be selected from the aldehydes discussed in this section and the aldehydes discussed in the section on organic solvents.

[0077] Carven: In some embodiments, the additive includes a carbene. The carbene may have the chemical formula X-(C:)-Y, where, Each of X and Y is H, Halo, -[C(R 1 )2]mC(R 2 )3, -C(O)-R 1 , or -C(=NR 1 )-R 2 , -NR 1 R 2 , -OR 2 , -SR 2 , or -C(R 2 ) can be independently selected from 3, where R 1 and R 2 m is independently selected from hydrogen, hydroxyl, aliphatic, haloaliphatic, haloheteroliphatic, heteroaliphatic, aromatic, aliphatic-aromatic, heteroaliphatic-aromatic, or any combination thereof, and m is an integer from 0 to 10. X and Y can optionally form cycloheteraliphatic groups with their respective bonding atoms. X and Y, together with their respective bonding atoms, can optionally form cycloaliphatic or cycloheteraliphatic groups.

[0078] Furthermore, the additive has the chemical formula R 1 -C + (R)newR 2 It may have a carbenium cation having R, R 1 , and, R 2 Each of these is independently selected from hydrogen, aliphatic, haloaliphatic, haloheteroliphatic, heteroaliphatic, aromatic, aliphatic-aromatic, heteroaliphatic-aromatic, or any combination thereof.

[0079] In some embodiments, each R, R 1 , and, R 2These are independently selected from alkyl, alkenyl, alkynyl, heteroalkyl, heteroalkenyl, heteroalkynyl, haloalkyl, haloalkenyl, haloalkynyl, haloheteroalkyl, haloheteroalkenyl, haloheteroalkynyl, aryl, heterocyclyl, heteroaryl, alkyl-aryl, alkenyl-aryl, alkynyl-aryl, alkyl-heterocyclyl, alkenyl-heterocyclyl, alkynyl-heterocyclyl, alkyl-heteroaryl, alkenyl-heteroaryl, alkynyl-heteroaryl, heteroalkyl-aryl, heteroalkenyl-aryl, heteroalkynyl-aryl, heteroalkyl-heterocyclyl, heteroalkenyl-heterocyclyl, heteroalkynyl-heterocyclyl, heteroalkyl-heteroaryl, heteroalkenyl-heteroaryl, heteroalkynyl-heteroaryl, or any combination thereof. In certain disclosed embodiments, the carbene may further be substituted with one or more substituents, such as alkoxyl, amide, amine, hydroxyl, thioether, thiol, acyloxy, silyl, cycloaliphatic, aryl, aldehyde, ketone, ester, carboxylic acid, acyl, acyl halogen, cyano, halogen, sulfonate, nitro, nitroso, quaternary amine, pyridinyl (or pyridinyl in which the nitrogen atom is functionalized with an aliphatic or aryl group), alkyl halogen, or any combination thereof. In any embodiment of the carbene, R 1 and R 2 Each of these can be selected independently.

[0080] In some embodiments, the additive may be a halocarbene if at least one of X or Y is a halo. Examples of non-limiting halocarbenes include dihalocarbenes such as dichlorocarbene and difluorocarbene.

[0081] In some embodiments, X=Y=-NR 1 R 2 If both conditions are met, the additive may be diaminocarbene. In one example, R 1 and R 2Each of these is independently aliphatic. Examples of diaminocarbenes include bis(diisopropylamino)carbene.

[0082] In other embodiments, at least one of X or Y = -NR 1 R 2 And R in X or Y 1 and R 2 If both of them, together with the nitrogen atom to which they are bonded, form a cycloheteraliphatic group, the additive can be a cyclic diaminocarbene. Examples of cyclic diaminocarbenes include bis(N-piperidyl)carbene, bis(N-pyrrolidinyl)carbene, and so on.

[0083] In one example, X or Y = -NR 1 R 2 It is both and R from X 1 Base and R from Y 2 When the group forms a cycloheteraliphatic group with each nitrogen atom to which it is bonded, the additive is an N-heterocyclic carbene. Examples of N-heterocyclic carbenes include imidazole-2-ylidene (e.g., 1,3-dimethyylimidazole-2-ylidene, 1,3-dimethyyl-4,5-dichloroimidazole-2-ylidene, 1,3-bis(2,6-diisopropylphenyl)imidazole-2-ylidene, 1,3-di-tert-butylimidazole-2-ylidene, etc.), imidazolidine-2-ylidene (e.g., 1,3-bis(2,6-diisopropylphenyl)imidazolidine-2-ylidene), triazole-5-ylidene (e.g., 1,3,4-triphenyl-4,5-dihydro-1H-1,2,4-triazole-5-ylidene), etc.

[0084] In some embodiments, X = -NR 1 R 2 and Y=-SR 2 And, R from X 1 Base and R from Y 2When the group forms a cycloheteraliphatic group with each of the nitrogen atoms to which it is bonded, the additive is an acyclic thioalkylaminocarbene. Examples of cyclic thioalkylaminocarbenes include thiazole-2-ylidene (e.g., 3-(2,6-diisopropylphenyl)thiazole-2-ylidene, etc.).

[0085] In some embodiments, X = -NR 1 R 2 and Y = -C(R 2 )3 and R from X 1 Base and R from Y 2 When a group forms a cycloheteraliphatic group with each of its bonded atoms, the additive is a cyclic alkylaminocarbene. Examples of cyclic alkylaminocarbenes include pyrrolidine-2-ylidene (e.g., 1,3,3,5,5-pentamethylpyrrolidine-2-ylidene, etc.) and piperidine-2-ylidene (e.g., 1,3,3,6,6-pentamethylpiperidine-2-ylidene, etc.).

[0086] Further examples of carbenes and their derivatives include compounds having a thiazole-2-ylidene moiety, a dihydroimidazole-2-ylidene moiety, an imidazole-2-ylidene moiety, a triazole-5-ylidene moiety, or a cyclopropenylidene moiety. Other carbenes and carbene analogs include aminothiocarbene compounds, aminooxycarbene compounds, diaminocarbene compounds, heteroaminocarbene compounds, 1,3-dithiolium carbene compounds, mesoionic carbene compounds (e.g., imidazoline-4-ylidene compounds, 1,2,3-triazoleylidene compounds, pyrazolineylidene compounds, tetrazoline-5-ylidene compounds, isoxazole-4-ylidene compounds, thiazole-5-ylidene compounds, etc.), cyclic alkylaminocarbene compounds, boranylidene compounds, silylene compounds, stanylene compounds, nitrene compounds, phosphinidene compounds, foiled carbene compounds, and the like. Further examples of carbenes include dimethylimidazole-2-ylidene, 1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazole-2-ylidene, (phosphanyl)(trifluoromethyl)carbene, bis(diisopropylamino)carbene, bis(diisopropylamino)cyclopropenylidene, 1,3-dimesityl-4,5-dichloroimidazole-2-ylidene, 1,3-diadamantylimidazole- This includes 2-ylidene, 1,3,4,5-tetramethylimidazole-2-ylidene, 1,3-dimethitylimidazole-2-ylidene, 1,3-dimethitylimidazole-2-ylidene, 1,3,5-triphenyltriazole-5-ylidene, bis(diisopropylamino)cyclopropenylidene, bis(9-antryl)carbene, norbornene-7-ylidene, dihydroimidazole-2-ylidene, methylidenecarbene, and others.

[0087] Organic acids: In some embodiments, the additive comprises an organic acid. The organic acid may have the chemical formula R-CO2H, where R is independently selected from hydrogen, aliphatic, haloaliphatic, haloheteroliphatic, heteroaliphatic, aromatic, aliphatic-aromatic, heteroaliphatic-aromatic, or any combination thereof. In certain embodiments, R is alkyl, alkenyl, alkynyl, heteroalkyl, heteroalkenyl, heteroalkynyl, haloalkyl, haloalkenyl, haloalkynyl, haloheteroalkyl, haloheteroalkenyl, haloheteroalkynyl, aryl, heteroaryl, alkyl-aryl, alkenyl-aryl, alkynyl-aryl, alkyl-heteroaryl, alkenyl-heteroaryl, alkynyl-heteroaryl, heteroalkyl-aryl, heteroalkenyl-aryl, heteroalkynyl-aryl, heteroalkyl-heteroaryl, heteroalkenyl-heteroaryl, heteroalkynyl-heteroaryl, or any combination thereof. In certain disclosed embodiments, R may be further substituted with one or more substituents, such as alkoxyl, amide, amine, thioether, hydroxyl, thiol, acyloxy, silyl, cycloaliphatic, aryl, aldehyde, ketone, ester, carboxylic acid, acyl, acyl halogen, cyano, halogen, sulfonate, nitro, nitroso, quaternary amine, pyridinyl (or pyridinyl in which the nitrogen atom is functionalized with an aliphatic or aryl group), alkyl halogen, or any combination thereof. In certain examples, the organic acid may be selected from formic acid and acetic acid.

[0088] Replace with: All examples of materials described herein include unsubstituted and / or substituted compounds. Non-limiting examples of substituents include, for example, 1, 2, 3, 4, or more substituents independently selected from the group consisting of: (1) C 1-6 Alkoxy (for example, -OR, where R is C) 1-6 (Alkyl), (2)C 1-6 Alkyl sulfinyl (for example, -S(O)-R, where R is C) 1-6 (Alkyl), (3)C1-6 Alkyl sulfonyl (for example, -SO2-R, where R is C) 1-6 (Alkyl), (4) Amine (e.g., -C(O)NR 1 R 2 or -NHCOR 1 , here, R 1 and R 2 Each of these is independently selected from hydrogen, aliphatic, heteroaliphatic, haloaliphatic, haloheteroaliphatic, aromatic, or any combination thereof, as defined herein, or R 1 and R 2 (1) 3-8 (12) Cycloalkyl, (13) Halo, (14) Heterocyclyl (e.g., a 5, 6, or 7-membered ring containing 1, 2, 3, or 4 non-carbon heteroatoms as defined herein), (15) Heterocyclyloxy (e.g., -OR, where R is a heterocyclyl as defined herein), (16) Heterocyclyloyl (e.g., -C(O)-R, where R is a heterocyclyl as defined herein), (17) Hydroxyl (e.g., -OH), (18) N-protected amino, (19) Nitro (e.g., -NO2), (10) Oxo (e.g., =O), (11) C 1-6 Thioalkoxy (for example, -SR, where R is C) 1-6 (Alkyl), (21) Thiol (e.g., -SH), (22) CO2R 1 , here, R 1 (a) hydrogen, (b) C 1-6 Alkyl, (c)C 4-18 Aryl, and (d)C 1-6 Alkyl-C 4-18 aryl (for example, -LR, where L is C)1-6 It is alkyl, and R is C 4-18 (23)-C(O)NR selected from the group consisting of aryls 1 R 2 , here, R 1 and R 2 Each of them is (a) hydrogen, (b) C 1-6 Alkyl, (c)C 4-18 Aryl, and (d)C 1-6 Alkyl-C 4-18 aryl (for example, -LR, where L is C) 1-6 It is alkyl, and R is C 4-18 (24)SO2R, independently selected from the group consisting of (aryls) 1 , here, R 1 (a)C 1-6 Alkyl, (b)C 4-18 Aryl, and (c)C 1-6 Alkyl-C 4-18 aryl (for example, -LR, where L is C) 1-6 It is alkyl, and R is C 4-18 (25)SO2NR selected from the group consisting of aryls 1 R 2 , here, R 1 and R 2 Each of them is (a) hydrogen, (b) C 1-6 Alkyl, (c)C 4-18 Aryl, and (d)C 1-6 Alkyl-C 4-18 aryl (for example, -LR, where L is C) 1-6 It is alkyl, and R is C 4-18 (26)NR, independently selected from the group consisting of (aryl) 1 R 2 , here, R 1 and R 2 Each of these consists of (a) hydrogen, (b) an N protecting group, and (c) C 1-6 Alkyl, (d)C 2-6 Alkenil, (e)C 2-6 Alkinyl, (f)C 4-18 Aryl, (g)C 1-6 Alkyl-C 4-18aryl (for example, -LR, where L is C) 1-6 And R is C 4-18 (It is an aryl compound), (h)C 3-8 Cycloalkyl, and (i)C 1-6 Alkyl-C 3-8 Cycloalkyl (for example, -LR, where L is C) 1-6 It is alkyl, and R is C 3-8 Independently selected from the group consisting of (cycloalkyl groups), where in one embodiment, none of the two groups are bonded to the nitrogen atom via a carbonyl or sulfonyl group.

[0089] In certain embodiments, the additive functions as a proton acceptor and HF2 - This can promote the formation of HF2. - It can actively etch one or more materials on the substrate, such as oxide materials or other materials.

[0090] Thermal energy is supplied. In some embodiments, the thermal energy supplies the heat that drives the chemical reaction. In some embodiments, the thermal energy does not include plasma. In some embodiments, the thermal energy is internal energy or kinetic energy. In some embodiments, the thermal energy is applied as at least one of thermal energy or chemical energy. In some embodiments, a light source emitting light or infrared radiation may be used to supply thermal energy to the surface of the stack 200. In some embodiments, radiant heat may be used to supply thermal energy to the surface of the stack 200. In some embodiments, an object such as a substrate support is in physical contact with the stack 200 through the substrate and supplies thermal energy through physical contact.

[0091] Figure 2B is a schematic cross-sectional view showing stack 204 after feature 224 has been partially etched into the silicon oxide layer.

[0092] Passivation process Following a partial thermal etching process (step 112) of stack 204, the next step in the circulation process (step 108) is a passivation process (step 116). In some embodiments, passivation provides a deposit on the sidewall of the feature, which is at least one of carbon-based, tungsten-based, molybdenum-based, and sulfur-based deposits. In some embodiments, passivation is provided by plasma-based deposition. In some embodiments, passivation is provided by thermal deposition. In some embodiments, thermal deposition does not use plasma. In some embodiments, passivation is provided by at least one of atomic layer deposition (ALD), chemical deposition (CVD), and self-assembled monolayer (SAM). In some embodiments, passivation provides a carbon-based deposit on the sidewall of the feature. In some embodiments, the carbon-based deposit is deposited on the sidewall using CVD.

[0093] Figure 2C is a schematic cross-sectional view showing the stack 204 after the passivation layer 228 has been deposited on the sidewall of feature 224. The passivation layer 228 is not drawn to scale in order to better illustrate the passivation layer 228.

[0094] Breakthrough process A breakthrough step (step 120) is provided in several embodiments. In some embodiments, the breakthrough step (step 120) may be at least one of plasma etching and chemical etching. In some embodiments, the breakthrough step utilizes plasma etching. In some embodiments, the breakthrough step (step 120) is not required if there is little or no passivation on the etch front, or if the subsequent etching step can etch the passivation layer deposited on the etch front.

[0095] Figure 2D is a schematic cross-sectional view showing stack 204 after the breakthrough process (process 120) has been provided. The passivation layer 228 at the etch front has been removed, leaving the passivation layer 228 deposited on the sidewalls of feature 224.

[0096] The cyclic process step 108 is repeated multiple times until etching is complete. Figure 2E is a schematic cross-sectional view showing the stack 204 after etching of feature 224 is complete. Further processes may be performed on the stack 204 in the chamber (step 124). The stack 204 is removed from the chamber (step 128). In the embodiment shown in the flowchart of Figure 1, all process steps are performed in place within the same chamber.

[0097] An advantage of the disclosed technology is that it achieves a high degree of selectivity during etching. Another advantage of the disclosed technology is that it provides extremely precise control of the etching rate and etching removal amount, in particular, compared to other thermally driven etching processes. By providing a circulating passivation process, sidewall etching that can be caused by thermal etching processes is reduced or eliminated, resulting in a more uniform feature width. Furthermore, some embodiments reduce the indentation of the SiN mask to less than 1.0 nanometer (nm).

[0098] An advantage of some embodiments is the ability of device manufacturers to have more precise control over the profiling of high aspect ratio features. Thermal etching is an inherently isotropic process. By providing sidewall protection, the resulting cyclic profiling becomes more anisotropic. Various embodiments allow for increased bottom CD for very high aspect ratio features. Various embodiments allow next-generation devices to rely on deeper structures with higher aspect ratios. Various embodiments reduce the cost of device manufacturing by reducing the number of steps required to construct high aspect ratio contacts. Various embodiments reduce the variability in feature width along the depth of the feature such that the width difference between any two points along the depth of the feature is less than 5%. Thermal etching allows for selective etching of silicon oxide against silicon nitride, silicon, silicon carbide, silicon germanium, and metal-containing layers.

[0099] Thermal etching cycle with plasma etching In some embodiments, a cyclic process of thermal etching and plasma etching is provided. Figure 3 shows a high-level flowchart that may be used in some embodiments. In some embodiments, the stack is placed in the etching chamber (step 304). Figure 4A is a schematic cross-sectional view showing the stack 404. In some embodiments, the stack 404 comprises a substrate 408 beneath a plurality of double layers 412 positioned below a patterned mask 416. In some embodiments, one or more layers may be placed between the substrate 408 and the plurality of double layers 412, and / or between the plurality of double layers 412 and the patterned mask 416. In some embodiments, the patterned mask 416 is a carbon-containing patterned mask, such as amorphous carbon. In some embodiments, there is no silicon-containing mask above the plurality of double layers 412 or above the patterned mask 416. In this example, the pattern of the patterned mask provides mask features 420 for high aspect ratio contacts. In some embodiments, the mask features 420 are formed before the stack 404 is placed in the etching chamber. In other embodiments, the mask feature 420 is formed while the stack 404 is in the etching chamber. In some embodiments, each bilayer 412 includes a silicon oxide layer 424 and a silicon nitride layer 428.

[0100] A circulating process (step 308) is provided for etching the stack. In some embodiments, the circulating process (step 308) includes a thermal etching step (step 312), a plasma etching step (step 314), a passivation step (step 316), and a breakthrough step (step 318). In some embodiments, the processes are performed in situ within the same processing chamber. In some embodiments, the circulating process (step 308) does not include the passivation step (step 316) and / or the breakthrough step (step 318).

[0101] The thermal etching process (step 312) may be the same as the thermal etching process (step 112) described above, in order to selectively etch the silicon oxide layer 424 from one or more silicon nitride layers 428. Figure 4B is a schematic cross-sectional view showing the stack 404 after the thermal etching process (step 312), where the thermal etching process (step 312) etches etching features 440 onto the exposed silicon oxide layer 424 to expose the silicon nitride layer 428.

[0102] Following the thermal etching process (step 312), plasma etching is provided (step 314). Plasma etching involves supplying an etching gas and plasmaizing the etching gas. In some embodiments, RF energy is used to convert the etching gas into plasma. The plasma is used to provide plasma etching. Plasma etching etches the silicon nitride layer 428. Figure 4C is a schematic cross-sectional view showing the stack 404 after plasma etching (step 314), where the plasma etching process (step 314) further etches etching features 440 into the exposed silicon oxide layer 428 to expose the silicon nitride layer 424. In some embodiments, plasma etching (step 314) partially etches the exposed silicon oxide layer.

[0103] After plasma etching (step 314), a passivation step may be provided (step 316). In some embodiments, passivation provides a deposit on the sidewalls of the features which is at least one of carbon-based, tungsten-based, molybdenum-based, and sulfur-based. In some embodiments, passivation is provided by plasma-based deposition. In some embodiments, passivation is provided by thermal deposition. In some embodiments, thermal deposition does not use plasma. In some embodiments, passivation is provided by at least one of atomic layer deposition (ALD), chemical deposition (CVD), and self-assembled monolayer (SAM). In some embodiments, passivation provides a carbon-based deposit on the sidewalls of the features. Figure 4D is a schematic cross-sectional view showing the stack 404 after the passivation step (step 316) has been provided to form a passivation layer 444.

[0104] Following the passivation step (step 316), a breakthrough step may be provided (step 318). In some embodiments, the breakthrough step (step 318) may be at least one of plasma etching and chemical etching. In some embodiments, the breakthrough step (step 318) is plasma etching using impulse ions. In some embodiments, the breakthrough step (step 318) is not required if there is little or no passivation on the etch front, or if the subsequent etching step can etch the passivation layer deposited on the etch front. Figure 4E is a schematic cross-sectional view showing the stack 404 after the breakthrough step (step 318) has been provided. The passivation layer 444 on the etch front has been removed, leaving the passivation layer 444 deposited on the sidewalls of the etching features 440.

[0105] The cyclic process is repeated multiple times until the etching feature 440 is complete. Figure 4F is a schematic cross-sectional view showing the stack 404 after the etching feature 440 is complete. Further processes may be performed on the stack 404 in the chamber (step 324). The stack 404 is removed from the chamber (step 328). In the embodiment shown in the flowchart of Figure 3, all process steps are performed in place within the same chamber.

[0106] A cyclic process (step 308) performing thermal etching (step 312) and plasma etching (step 314) allows for more control parameters for etching the silicon oxide and other material bilayers. The thermal etching (step 312) provides selective etching of silicon oxide, while plasma etching (step 314) provides etching of the other material. Thermal etching can etch silicon oxide more quickly than plasma etching. The addition of a passivation step (step 316) allows etching of deeper silicon oxide layers 424 without lateral etching of the sidewalls of the previously etched silicon oxide layers 424. Thermal etching allows etching of high aspect ratio silicon oxide while reducing twisting and non-circularity. Some embodiments provide a high depth H to width W1 ratio as shown in Figure 4E. Furthermore, the variation in W1 along the depth is reduced. Additionally, the feature width W1 at the top of the feature is close to the feature width W2 at the bottom of the feature. In some embodiments, the aspect ratio of depth H to width W1 is in the range of 4:1 to 20:1. In some embodiments, the width W1 has a CD in the range of 10 nm to 50 nm.

[0107] In some embodiments, a bilayer of silicon oxide and other materials in the stack may be etched. In some embodiments, a triple layer comprising a silicon oxide layer and two layers of two other materials may be etched. In some embodiments, a cyclic process comprising thermal etching and a single plasma etching may be used to etch the triple layer. In some embodiments, a cyclic process comprising thermal etching followed by two separate etching processes may be used to etch the triple layer. In this specification and the claims, at least two layers include bilayers, triple layers, and more than one multilayer arranged together. A multilayer of three or more layers may be layers of different materials or may have several layers of the same material, where not all layers are necessarily of the same material. In some embodiments, thermal etching is plasma-free etching. In some embodiments, plasma may be supplied during thermal etching to avoid plasma re-ignition and / or to avoid etching stoppages due to sputtering of sidewall material to the etch front.

[0108] Figure 5 is a schematic diagram showing an etching reactor system 500 that may be used in several embodiments. In some embodiments, the etching reactor system 500 comprises a gas / vapor distribution plate 506 providing gas and vapor inlets and a pedestal 508, within an etching chamber 509 surrounded by chamber walls 552. Within the etching chamber 509, a stack 204 is positioned on the pedestal 508, where the pedestal 508 functions as a wafer support. The pedestal 508 may be biased from a pedestal power supply 548. A gas / vapor source 510 is connected to the etching chamber 509 through the gas / vapor distribution plate 506. In some embodiments, the gas / vapor source 510 includes a vapor source 512, a gas source 516, and may further include other sources 518. The vapor source 512 includes a halogen vapor source and a vapor catalyst source. The gas source 516 includes at least one of a passivation gas source and an etching plasma gas source. A pedestal temperature controller 550 is connected to the pedestal 508. The pedestal temperature controller 550 may be used to heat the pedestal through a pedestal heater 517 to supply thermal energy. In other embodiments, thermal energy may be provided through other heater configurations. A plasma power supply (such as a radio frequency (RF) source 530) supplies power to the lower electrode and / or upper electrode, which in some embodiments are the pedestal 508 and the gas / vapor distribution plate 506, respectively. In some embodiments, 400 kHz, 60 MHz, and optionally 2 MHz and 27 MHz power supplies constitute the RF source 530 and the pedestal power supply 548. In some embodiments, the upper electrode is grounded. In some embodiments, one generator is provided for each frequency. In another embodiment, multiple generators may be in separate RF sources, or separate RF generators may be connected to different electrodes. For example, the upper electrode may have inner and outer electrodes connected to different RF sources. Other configurations of RF sources and electrodes may be used in other embodiments.An exhaust pump 520 provides an outlet for exhausting gas from the etching chamber 509. A controller 535 is controllably connected to the RF source 530, the pedestal power supply 548, the exhaust pump 520, and the gas / vapor source 510. An example of such an etching chamber is the Flex® etching system from Lam Research, Inc. of Fremont, California. The processing chamber may be a CCP (capacitance-coupled plasma) reactor or an ICP (inductively coupled plasma) reactor. In some embodiments, the circulation process is performed in situ within the etching chamber 509 with the stack 204 supported on the pedestal 508.

[0109] Figure 6 is a high-level block diagram showing a computer system 600 suitable for implementing the controller 535 used in the embodiment. The computer system 600 may have many physical forms, ranging from integrated circuits, printed circuit boards, and small portable devices to large supercomputers. The computer system 600 comprises one or more processors 602 and may further include an electronic display device 604 (for displaying images, text, and other data), main memory 606 (e.g., random access memory (RAM)), storage device 608 (e.g., hard disk drive), removable storage device 610 (e.g., optical disk drive), user interface device 612 (e.g., keyboard, touchscreen, keypad, mouse, or other pointing device), and communication interface 614 (e.g., wireless network interface). The communication interface 614 enables the transfer of software and data between the computer system 600 and external devices via a link. The system may further include a communication infrastructure 616 (e.g., a communication bus, crossover bar, or network) to which the aforementioned devices / modules are connected.

[0110] The information transmitted via the communication interface 614 may be in the form of a signal, such as an electronic signal, an electromagnetic signal, an optical signal, or any other signal that can be received by the communication interface 614 via a communication link that carries the signal, and may be carried out using wires, i.e., cables, optical fibers, telephone lines, mobile phone links, radio frequency links, and / or communication channels. It is assumed that one or more processors 602 can receive information from or output information to a network using such a communication interface 614 when performing the steps of the method described above. Furthermore, embodiments of the method may be performed by a single processor or in cooperation with a remote processor that shares part of the processing via a network such as the Internet.

[0111] The term "non-temporary computer-readable medium" is generally used to refer to media such as main memory, secondary memory, removable storage, and storage devices (such as hard disks, flash memory, disk drive memory, CD-ROMs, and other forms of persistent memory), and should not be interpreted to encompass temporary objects such as carrier waves or signals. Examples of computer code include machine code, such as code generated by a compiler, and files containing high-level language code executed by a computer using an interpreter. A computer-readable medium may also be computer code, which represents a set of instructions that are transmitted by computer data signals embodied in a carrier wave and that can be executed by a processor.

[0112] While the present disclosure has been described with reference to several preferred embodiments, there are substitutes, modifications, replacements, and various alternative equivalents within the scope of this disclosure. It should also be noted that there are numerous other ways of carrying out the methods and apparatus of this disclosure. Therefore, the appended claims should be interpreted as encompassing all substitutes, modifications, replacements, and equivalents that fall within the true spirit and scope of this disclosure. As used herein, the expression “A, B, or C” should be interpreted as meaning a logic (“A OR B OR C”) using a non-exclusive OR “OR”, and not as meaning “only one of A, B, or C”. Each step in the process may be optional and not mandatory. Various embodiments may omit one or more steps, or provide steps in a different order. Furthermore, various embodiments may provide different steps simultaneously rather than sequentially.

Claims

1. A method for etching features within a stack, comprising the step of providing multiple cycles, each cycle being: a) A step of providing a thermal etching step for etching the features within the stack, wherein the stack comprises at least one silicon oxide layer, and the thermal etching step is A process of supplying a thermal etching gas for a vapor phase containing a halogen-containing vapor or gas and a vapor catalyst, A step comprising supplying thermal energy to drive a reaction that etches the features within the stack, b) A step of providing a passivation process for depositing a passivation layer on the side wall of the feature, A method that includes [a certain feature].

2. A method according to claim 1, wherein the step of providing passivation is to provide a sediment which is at least one of carbon-based, tungsten-based, molybdenum-based, and sulfur-based.

3. A method according to claim 1, wherein the step of providing passivation is provided by at least one of chemical vapor deposition, chemical vapor deposition, self-assembled monolayer, and atomic layer deposition.

4. A method according to claim 1, wherein each cycle further comprises the step of providing the passivation breakthrough.

5. A method according to claim 4, wherein the steps of providing thermal etching, providing passivation, and providing a breakthrough are performed in situ within a chamber.

6. A method according to claim 1, wherein the steps of providing thermal etching and providing passivation are performed in situ within a chamber.

7. A method according to claim 1, wherein the step of providing the thermal etching further includes the step of providing a pressure of 0.2 to 10 Torr.

8. A method according to claim 1, wherein the halogen-containing vapor or gas is a hydrogen fluoride-containing vapor or gas.

9. A method according to claim 1, wherein the step of providing passivation provides carbon-based sediments.

10. The method according to claim 1, wherein the vapor catalyst is With organic solvents and / or water, Additives and Conveying gas and Methods that include...

11. A method according to claim 10, wherein the additive comprises a heterocycle.

12. A method according to claim 10, wherein the additive comprises an amine.

13. A method for etching features within a stack, comprising the step of providing multiple cycles, each cycle being: a) A process of providing plasma etching, b) A step of providing thermal etching for etching features within the stack, wherein the stack comprises at least a bilayer, and at least one of the bilayers is a silicon oxide layer, and the step of providing thermal etching is A process of supplying a thermal etching gas for a vapor phase containing a halogen-containing vapor or gas and a vapor catalyst, A step comprising supplying thermal energy to drive a reaction that etches the features within the stack, Methods that include...

14. A method according to claim 13, wherein the step of providing the thermal etching further provides a pressure of 0.2 to 10 Torr.

15. A method according to claim 13, wherein each cycle further comprises the step of (c) providing passivation for depositing a passivation layer on the sidewall of the feature.

16. A method according to claim 15, wherein each cycle further comprises the step of providing the passivation breakthrough.

17. A method according to claim 16, wherein the steps of providing plasma etching, providing thermal etching, providing passivation, and providing a breakthrough are performed in situ within a chamber.

18. A method according to claim 15, wherein the steps of providing plasma etching, providing thermal etching, and providing passivation are performed in situ within a chamber.

19. A method according to claim 15, wherein the step of providing passivation provides carbon-based sediments.

20. A method according to claim 13, wherein the halogen-containing vapor or gas includes a hydrogen fluoride-containing vapor or gas.

21. The method according to claim 13, wherein the vapor catalyst is With organic solvents and / or water, Additives and Conveying gas and Methods that include...

22. An apparatus for etching a substrate, a. A reaction chamber configured to provide a pressure of approximately 0.2 to 10 Torr within the reaction chamber, b. A substrate support configured to support the substrate within the reaction chamber, c. At least one inlet for introducing the gas mixture into the reaction chamber, d. A halogen vapor or gas source for supplying halogen vapor or gas to the at least one inlet, e. A steam catalyst source for supplying the steam catalyst to the at least one inlet, f. At least one of the passivation gas source and etching plasma gas source connected to the at least one inlet, g. A heater for supplying thermal energy to the substrate, h. An outlet for removing vapor from the reaction chamber, f. A controller configured to provide a circulating process, wherein the circulating process is: Thermal etching process, A controller including at least one of a passivation process and a plasma etching process, A device equipped with the following features.

23. The apparatus according to claim 22, further comprising a plasma power supply for supplying plasma energy to the reaction chamber.

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