Selective deposition

Abstract

A method, system and apparatus for selectively forming alumina on a first surface of a substrate relative to a different second surface of the substrate, the process comprising one or more super-cycles, the super-cycles comprising sub-cycles: a) by one or more selective deposition sub-cycles, the method includes the steps of: a) selectively depositing aluminum nitride on a first surface of a substrate relative to a different second surface of the substrate, b) oxidizing at least a portion of the aluminum nitride by one or more oxidation sub-cycles, c) etching the aluminum oxide or the aluminum nitride, or a combination thereof, by one or more thermal etching sub-cycles, where the etchant is an organic halide, and c) etching the aluminum oxide or the aluminum nitride, or a combination thereof, by one or more thermal etching sub-cycles. And repeating the sub-cycles a), b) or c), or a combination thereof, until alumina of a desired thickness is formed on the first surface.

Description

Technical Field

[0001] The present application relates to selectively depositing a material containing aluminum, nitrogen and / or oxygen, such as a film containing Al and N and / or Al and O, on a first surface of a substrate relative to a second surface. Background Art

[0002] Integrated circuits are currently manufactured through a sophisticated process in which various material layers are sequentially constructed in a predetermined arrangement on a semiconductor substrate.

[0003] The predetermined arrangement of material on the semiconductor substrate is usually achieved by depositing the material over the entire substrate surface and then removing the material from predetermined areas of the substrate, for example by depositing a mask layer and a subsequent selective etching process.

[0004] In some cases, the number of steps involved in fabricating an integrated surface on a substrate can be reduced by utilizing a selective deposition process, wherein a material is selectively deposited on a first surface relative to a second surface, without requiring or reducing the need for subsequent processing. Methods for selectively depositing on a first surface of a substrate relative to a different second surface of the substrate are disclosed herein.

[0005] Any discussion set forth in this section, including discussion of problems and solutions, has been included in the present disclosure merely to provide context for the present disclosure. Such discussion should not be construed as an admission that any or all information was known at the time the present invention was made, or constitutes prior art. Summary of the invention

[0006] This summary is provided to introduce some concepts in a simplified form. These concepts are further described in detail in the detailed description of the example embodiments disclosed below. This summary is not intended to necessarily identify the key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

[0007] Disclosed herein are processes, systems, and apparatus for selectively forming aluminum oxide on a first surface of a substrate relative to a different second surface of the substrate, where examples may include one or more super cycles comprising sub-cycles: a) selectively depositing aluminum nitride on the first surface of the substrate relative to a different second surface of the substrate via one or more selective deposition sub-cycles, b) oxidizing at least a portion of the aluminum nitride via one or more oxidation sub-cycles, c) etching the aluminum oxide or aluminum nitride, or a combination thereof, via one or more thermal etching sub-cycles, where the etchant is an organic halide, and where sub-cycles a), b), or c), or a combination thereof, may be repeated until a desired thickness of aluminum oxide is formed on the first surface.

[0008] In some examples, aluminum oxide may be selectively formed on a first surface of the substrate relative to a second, different surface of the substrate.

[0009] In some examples, one or more super cycles may also include exposing the substrate to a pre-treatment reactant.

[0010] In various examples, the substrate may be exposed to a pre-treatment reactant prior to one or more selective deposition sub-cycles.

[0011] In certain examples, pre-treating the reactants may include a plasma.

[0012] In some examples, the plasma may be generated from a gas including H 2 .

[0013] In some examples, one or more selective deposition sub-cycles may include: contacting the substrate with a first vapor precursor comprising aluminum; and contacting the substrate with a second vapor precursor comprising nitrogen.

[0014] In a specific example, the first vapor-phase precursor including aluminum may include tri-tert-butylaluminum (TTBA), trimethylaluminum (TMA), or triethylaluminum (TEA).

[0015] In various examples, the second gas-phase precursor comprising nitrogen may comprise NH 3 .

[0016] In some examples, the one or more oxidation sub-cycles can include contacting the substrate with a first gas-phase precursor comprising oxygen.

[0017] In some examples, the first gas-phase precursor including oxygen may include O3, H2O, H2O2, O2, atomic oxygen, oxygen plasma, native oxide, exposure to the environment or oxygen radicals, or mixtures thereof.

[0018] In a particular example, one or more thermal etch sub-cycles can include contacting the substrate with a first vapor phase halide etch reactant and contacting the substrate with a second vapor phase etch reactant comprising aluminum.

[0019] In some examples, the first gas-phase halide etch reactant can include HF, CCl4, BCl3, CF4, hacac, NF3, hexafluoroacetylacetonate (hhfac), trifluoroacetylacetonate, NF3, or NbF5, or a combination thereof.

[0020] In some examples, the second vapor-phase etch reactant including aluminum may include trimethylaluminum (TMA) or triethylaluminum (TEA).

[0021] In certain embodiments, one or more thermal etch sub-cycles may be performed at a process temperature of about 25°C-500°C.

[0022] In various embodiments, the first surface may be a conductive surface and the different second surface may be a dielectric surface.

[0023] In certain embodiments, the first surface may include W, Co, Ru, TiN, Cu, Mo, MoN, TaN, or Ta, or combinations thereof.

[0024] In some embodiments, the second surface may include SiO2, SiN, SiGe, SiOxC, SiOxN, HfOx, ZrOx, HfSiOx, SiOxCyNz or ZrSiOx, or a combination thereof, where x=0-2, y=0-2, z=0-2.

[0025] In various embodiments, one or more selective deposition sub-cycles may be repeated 1 to about 1000 times, and one or more thermal etching sub-cycles may be repeated 1 to about 1000 times.

[0026] In a particular example, one or more thermal etch sub-cycles can include contacting the substrate with a first vapor phase halide etch reactant comprising hhfac and a second vapor phase etch reactant comprising trimethylaluminum (TMA).

[0027] In order to summarize the present disclosure and the advantages achieved relative to the prior art, certain objects and advantages of the present disclosure have been described above. Of course, it should be understood that all of these objects or advantages may not be achieved according to any specific embodiment or example of the present disclosure. Thus, for example, those skilled in the art will recognize that the examples disclosed herein can be implemented in a manner that achieves or optimizes one advantage or a group of advantages taught or suggested herein, without necessarily achieving other objects or advantages taught or suggested herein.

[0028] All of these examples are within the scope of the present disclosure.These and other embodiments will become apparent to those skilled in the art through the following detailed description of certain examples with reference to the accompanying drawings, the present disclosure not being limited to any particular examples discussed. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Although the specification concludes with claims that particularly point out and distinctly claim what are considered to be embodiments or examples of the present disclosure, advantages of examples of the present disclosure may be more readily ascertained from the description of certain examples of the present disclosure when read in conjunction with the accompanying drawings. Elements having the same element number are identical in all drawings.

[0030] Figure 1 A deposition process flow for selectively depositing a material containing Al and N and / or O on a first surface of a substrate relative to a different second surface of the same substrate is shown;

[0031] Figure 2A deposition process flow for selectively depositing Al and N and / or O on a first surface of a substrate relative to a different second surface of the same substrate is shown;

[0032] FIG. 3A to FIG. 3C A deposition process flow is shown for selectively depositing a material containing Al and N and / or O on a first surface of a substrate relative to a different second surface of the same substrate, including a selective deposition sub-cycle and an atomic layer etching sub-cycle; and

[0033] Figure 4 A deposition process flow is shown for selectively depositing a material containing Al and N and / or O on a first surface of a substrate relative to a different second surface of the same substrate. DETAILED DESCRIPTION

[0034] The detailed description of various examples herein refers to the accompanying drawings, which illustrate exemplary examples by way of illustration. Although these exemplary examples are described in sufficient detail to enable those skilled in the art to practice the present disclosure, it should be understood that other examples may be implemented without departing from the spirit and scope of the present disclosure, and logical, chemical and / or mechanical changes may be made. Therefore, the detailed description here is only for the purpose of illustration, not for limitation. For example, the steps described in any method or process description may be performed in any combination and / or order, and are not limited to the presented combination and / or order. In addition, one or more steps from one of the disclosed methods or processes may be combined with one or more steps from another disclosed method or process in any suitable combination and / or order. In addition, any function or step may be outsourced to one or more third parties or performed by a third party. In addition, any reference to the singular includes plural examples, and any reference to more than one component may include a singular example.

[0035] Although certain embodiments and examples are disclosed below, those skilled in the art will appreciate that the disclosure extends beyond the specifically disclosed examples and / or uses of the disclosure and obvious modifications and equivalents thereof. Therefore, it is intended that the scope of the disclosure should not be limited by the specific examples described herein.

[0036] The illustrations presented herein are not meant to be actual views of any particular material, apparatus, structure, or device, but are merely representations of examples used to describe the present disclosure.

[0037] As used herein, the term "substrate" may refer to any underlying material or materials that may be used or upon which a device, circuit, or film / layer may be formed.

[0038] As used herein, the term "atomic layer deposition" (ALD) may refer to a vapor deposition process in which a deposition cycle, preferably a plurality of consecutive deposition cycles, is performed in a processing chamber. Typically, during each cycle, a precursor is chemically adsorbed to a deposition surface (e.g., a substrate surface or a previously deposited underlying surface, such as material from a previous ALD cycle) to form a monolayer or sub-monolayer that is not easily reacted with additional precursors (i.e., a self-limiting reaction). Thereafter, if desired, a reactant (e.g., another precursor or a reactive gas) may be subsequently introduced into the processing chamber for converting the chemically adsorbed precursor into the desired material on the deposition surface. Typically, the reactant is capable of further reacting with the precursor. In addition, a purge step may also be utilized during each cycle to remove excess precursor from the processing chamber and / or excess reactant and / or reaction byproducts from the processing chamber after the chemically adsorbed precursor is converted. In addition, the term "atomic layer deposition" as used herein is also meant to include processes designated by related terms, such as, "chemical vapor atomic layer deposition", "atomic layer epitaxy" (ALE), molecular beam epitaxy (MBE), gas source MBE or organometallic MBE, and chemical beam epitaxy when performed with alternating pulses of a precursor composition, a reactive gas, and a purge gas (e.g., an inert carrier gas).

[0039] As used herein, the term "chemical vapor deposition" (CVD) may refer to any process in which a substrate is exposed to one or more volatile precursors that react and / or decompose on the substrate surface to produce the desired deposit.

[0040] As used herein, the terms "layer", "film" and / or "thin film" may refer to any continuous or discontinuous structure and material deposited by the methods disclosed herein. For example, a "layer", "film" and / or "thin film" may include a 2D material, nanorods, nanotubes or nanoparticles, or even a partial or complete molecular layer or a partial or complete atomic layer or clusters of atoms and / or molecules. A "layer", "film" and / or "thin film" may include a material or layer having pinholes, but still at least partially continuous.

[0041] In addition, in the present disclosure, any two numbers of a variable may constitute a feasible range for the variable, and any range indicated may include or exclude endpoints. In addition, any values ​​of the variables indicated (regardless of whether they are expressed as "about") may refer to exact values ​​or approximate values, and include equivalents, and may refer to average values, median values, representative values, majority values, etc. In addition, in the present disclosure, the terms "including", "consisting of" and "having" may independently refer to "generally or broadly including", "comprising", "essentially consisting of" or "consisting of" in some examples. In the present disclosure, the meaning of any definition does not necessarily exclude the common and customary meanings in some examples.

[0042] refer to Figure 1, a material containing Al and N and / or O can be selectively deposited on a first surface of a substrate including a first surface and a different second surface by an ALD-type deposition process 100, the deposition process 100 comprising at least one cycle, the cycle comprising: contacting the substrate with a first gaseous precursor containing Al at step 120; removing excess first precursor and reaction byproducts, if any, from the substrate at step 130; contacting the substrate with a second gaseous precursor containing nitrogen at step 140; removing excess second precursor and any gaseous byproducts from the substrate at step 150; and optionally, repeating the contacting and removing steps at step 160 until a desired thickness of the material containing Al and N and / or O has been formed. In some examples, the material containing Al and N and / or O can include, for example, AlN, non-stoichiometric aluminum oxide Al2O3, and / or aluminum oxynitride (ALON).

[0043] In some examples, before starting the deposition process 100, one or more surfaces of the substrate can be subjected to a pretreatment process 110. The pretreatment process can enhance the selectivity of the selective deposition process 100. In some embodiments, before starting the deposition process 100, the pretreatment process can enhance the deposition of the material containing Al and N and / or O on one surface relative to one or more different surfaces. In an example, before starting the deposition process 100, the pretreatment process can inhibit the deposition of the material containing Al and N and / or O on one surface relative to one or more different surfaces.

[0044] exist Figure 1 In the embodiment of the present invention, this is represented by step 110, where the substrate can be exposed to a pretreatment reactant, such as a plasma, before depositing the material containing Al and N and / or O. In some examples, the pretreatment reactant can include oxygen, oxygen radicals, atomic oxygen, oxygen plasma, or a combination thereof. In some examples, the pretreatment reactant can include nitrogen, nitrogen radicals, atomic nitrogen, nitrogen plasma, or a combination thereof. In one example, the pretreatment reactant can include hydrogen, hydrogen radicals, atomic hydrogen, hydrogen plasma, or a combination thereof.

[0045] In some embodiments utilizing a pretreatment process, wherein the substrate is exposed to a pretreatment reactant comprising an oxygen plasma, O2 may be provided, for example, at about 1 to about 2000 sccm, more preferably at about 5 to about 1000 sccm, and most preferably at about 50 to about 500 sccm. In one example, O2 may be provided at about 300 sccm. In some examples, utilizing a pretreatment process, wherein the substrate is exposed to a pretreatment reactant comprising a nitrogen plasma, N2 may be provided, for example, from about 1 to about 5000 sccm, more preferably from about 5 to about 2000 sccm, and most preferably from about 50 to about 500 sccm. In one example, N2 may be provided at about 300 sccm. In some embodiments, in a pretreatment process wherein the substrate is exposed to a pretreatment reactant comprising a hydrogen plasma, H2 may be provided, for example, at about 1 to about 2000 sccm, more preferably at about 5 to about 1000 sccm, and most preferably at about 10 to about 100 sccm. In one example, H2 may be provided at about 50 sccm. Similar conditions may be used for other types of plasmas.

[0046] In some examples, the pretreatment process may include exposing the substrate to a pretreatment reactant at a pretreatment temperature. In one example, the pretreatment temperature may be higher than about 20°C. In some embodiments, the pretreatment temperature may be between about 20°C and about 500°C, more preferably between about 50°C and about 450°C, more preferably between about 150°C and about 400°C. In one example, the pretreatment temperature may be substantially the same as the deposition temperature. In some examples, the pretreatment temperature may be different from the deposition temperature. In one example, the plasma may be generated at a power of less than about 2500W, such as about 1 to about 1000W, about 1 to about 500W, or about 1 to about 200W or less. In some embodiments, the plasma may be generated at a power of 50W. In one example, the plasma may be generated at a power of 100W.

[0047] In some examples, the plasma is provided for less than about 200 seconds, such as about 180 seconds or less, about 60 seconds or less, about 30 seconds or less, about 10 seconds or less, or about 3 seconds or less.

[0048] In some embodiments, the plasma is formed in a reactor. In some embodiments, the plasma can be formed in situ on top of or immediately adjacent to the substrate. In other embodiments, the plasma is formed upstream of the reaction chamber in a remote plasma generator, and the plasma products are directed to the reaction chamber to contact the substrate. As will be appreciated by those skilled in the art, in the case of a remote plasma, the path to the substrate can be optimized to maximize electrically neutral species and minimize ion survival before reaching the substrate.

[0049] In one example, after the pretreatment process and before the selective deposition process begins, the treated substrate is not exposed to the surrounding environment. In some embodiments, after the pretreatment process and before the selective deposition process begins, the treated substrate is not exposed to air.

[0050] In one example, the pretreatment process can be used to enhance the selectivity of a subsequent selective deposition process. In some examples, the pretreatment process can enhance the selective deposition of a material containing Al and N and / or O on a first surface relative to a different second surface. In one example, the pretreatment process can enhance the selectivity of a subsequent selective deposition process by more than about 2 times, more than about 5 times, or more than about 10 times.

[0051] In some embodiments, the pretreatment process may be performed in the same reaction chamber or reactor as the subsequent deposition process 100. In one example, the pretreatment process may be performed in a different reaction chamber or reactor than the subsequent deposition process 100.

[0052] Still refer to Figure 1 At step 120, the substrate is contacted with a first precursor comprising Al. In some examples, the first precursor is introduced into the reaction chamber in the form of a gas phase pulse and contacted with the substrate surface. The conditions are preferably selected so that no more than about one monolayer of the precursor is adsorbed on the substrate surface in a self-limiting manner. However, in some embodiments, the conditions can be selected so that more than one monolayer of the precursor can be formed.

[0053] The first precursor pulse is preferably provided in gaseous form. For purposes of this specification, a first precursor gas is considered "volatile" if it exhibits sufficient vapor pressure under process conditions to deliver the substance to the workpiece in sufficient concentration to saturate the exposed surface.

[0054] In one example, the first precursor contacts the substrate for about 0.01 seconds to about 60 seconds, about 0.02 seconds to about 30 seconds, about 0.025 seconds to about 20 seconds, about 0.05 seconds to about 5.0 seconds, about 0.05 seconds to about 2.0 seconds, or about 0.1 seconds to about 1.0 seconds.

[0055] The first precursor used in an ALD type process can be a solid, liquid or gaseous material under standard conditions (room temperature and atmospheric pressure) as long as the first precursor is in the gas phase before being introduced into the reaction chamber and contacting the substrate surface.

[0056] In step 130, optional purge operation can be implemented to remove excessive first precursor and reaction byproducts from substrate surface, if any, such as by purging with an inert gas such as nitrogen or argon pulse.Purge reaction chamber means to remove gaseous phase precursor and / or gaseous phase byproducts from reaction chamber, such as by evacuating reaction chamber with a vacuum pump and / or by replacing the gas in the reactor with an inert gas such as argon or nitrogen.Typical purge time is about 0.05 to 20 seconds, more preferably about 1 to 10 seconds, and even more preferably about 1 to 2 seconds.However, if necessary, other purge times can be used, such as when deposited layers on other structures with extremely high aspect ratio or needing to have complex surface morphology.Skilled technicians can easily determine suitable purge time according to specific circumstances.

[0057] However, in other embodiments, removing excess first precursor and reaction byproducts (if any) can include moving the substrate so that the first precursor no longer contacts the substrate. In some embodiments, no precursor can be removed from various parts of the chamber. In one example, the substrate is moved from a portion of the chamber containing the first precursor to another portion of the chamber containing the second precursor or no precursor at all. In some examples, the substrate is moved from a first reaction chamber to a different second reaction chamber.

[0058] At step 140, the substrate is contacted with a second vapor-phase precursor comprising N. In one example, the second precursor is pulsed into a chamber where it reacts with the first precursor bound to the first surface of the substrate. The reaction typically forms up to about a monolayer of the material comprising Al and N and / or O on the substrate. However, in some embodiments, more than one molecular layer of the material comprising Al and N and / or O is formed on the substrate.

[0059] In some embodiments, the second precursor may include nitrogen plasma or nitrogen radicals. In such embodiments, the nitrogen gas may be excited within the reaction chamber or upstream of the reaction chamber. Where a plasma is desired, the unexcited second precursor stream may include a purge gas such that after the substrate has been exposed to the nitrogen plasma for a desired period of time, the plasma generator may be turned off and the nitrogen precursor stream itself used to purge excess nitrogen plasma and unreacted byproducts from the reaction chamber.

[0060] While those skilled in the art will recognize that any number of suitable second precursors may be used, suitable second precursors include nitrogen-containing compounds that react favorably with the ligands of a previously or subsequently deposited first precursor. Thus, the selection of a suitable second precursor may depend on the particular first precursor used and the nature of the ligands in the first precursor.

[0061] In some embodiments, the second precursor contacts the substrate for about 0.01 second to about 60 seconds, about 0.02 second to about 30 seconds, about 0.025 second to about 20 seconds, about 0.05 second to about 5.0 seconds, about 0.05 second to about 2.0 seconds, or about 0.1 second to about 1.0 second. However, depending on the reactor type, substrate type and surface area thereof, the second precursor contact time can even be higher than 10 seconds. In some embodiments, the contact time can be the order of several minutes. Technicians can easily determine the optimal contact time according to the specific circumstances.

[0062] The concentration of the second precursor in the reaction chamber may be about 0.01 vol% to about 99.0 vol%. And the second precursor may flow through the reaction chamber at a rate of about 1 standard cm3 / min to about 4000 standard cm3 / min.

[0063] At step 150, an optional purge operation may be performed to remove excess second precursor and gaseous byproducts of the surface reaction (if any) from the substrate, as described above for step 130. In one example, excess precursor and reaction byproducts are preferably removed with the aid of an inert gas.

[0064] At step 160, the contacting and removing steps may optionally be repeated until a desired thickness of the Al- and N-containing material has been formed on the first surface of the substrate, leaving no more than about one molecular monolayer per cycle. In one example, step 160 may be repeated from about 1 to about 1000 times, or any suitable number of cycles. In some cases, it may be desirable to achieve at least partial decomposition of at least one of the various precursors. Thus, in some embodiments, conditions may be selected such that more than one molecular layer of the Al- and N-containing material is formed on the substrate in each deposition cycle.

[0065] At step 180, the deposited AlN may be exposed to an optional oxidation sub-cycle (e.g., "oxidation treatment"). Such an oxidation sub-cycle may include contacting the AlN on the substrate with an oxidant, the oxidant including an oxygen-containing gas-phase precursor, wherein the oxygen-containing gas-phase precursor includes, for example, O3, H2O, H2O2, O2, atomic oxygen, oxygen plasma, native oxide, exposure to an environment (e.g., including atmospheric oxygen and moisture) or oxygen radicals, or a mixture thereof, to oxidize the AlN to aluminum oxide.

[0066] In some embodiments, the oxidation treatment of the oxidation sub-cycle of step 180 may include exposing the substrate to oxygen or an oxygen-containing precursor provided in the reaction chamber and allowing contact with the substrate surface. The oxygen treatment phase may be part of one or more deposition cycles, or may be its own sub-cycle 161. The oxygen treatment sub-cycle 161 may be entered after any appropriate step of the super cycle 100. In some examples, a second metal phase may be provided in one or more deposition cycles. The oxidation phase or other desired phase may be after the Al phase or the N phase, but in either case, in some embodiments, it may be desirable to remove excess oxygen (or other reactants) and any reaction byproducts from the reaction space before proceeding to the next phase (purge step 190). In one example, additional phases, such as oxygen or additional metal phases, may be provided after the final deposition cycle or intermittently during the deposition process.

[0067] In some embodiments, the oxidation treatment may be performed before the deposited film of the material containing Al and N and / or O is continuous or closed. In one example, the oxidation treatment may be performed after about every 2 deposition cycles, about every 4 deposition cycles, about every 6 deposition cycles, about every 10 deposition cycles, about every 25 deposition cycles, about every 50 deposition cycles, about every 100 deposition cycles, about every 200 deposition cycles, about every 300 deposition cycles, about every 400 deposition cycles, about every 500 deposition cycles, about every 1000 deposition cycles, or any other suitable number of deposition cycles.

[0068] The disclosed Al and N and / or O containing material ALD process 100 may include one or more cycles. Some embodiments include repeating at least about 2 cycles, or about 4 cycles, or about 8 cycles, or about 10 cycles, or about 20 cycles, or about 50 cycles, or about 100 cycles, or about 200 cycles, or about 300 cycles, or about 400 cycles, or about 500 cycles, or about 1000 cycles, or any other suitable number of cycles.

[0069] In some examples, the substrate surface and / or the Al and N and / or O containing material may optionally be subjected to a plasma treatment process. Figure 1In the embodiment of the present invention, this is represented by step 170. In one example, the plasma treatment process can be performed after more than one deposition cycle has been performed. In some embodiments, the plasma treatment process can be performed before the deposited Al and N and / or O-containing material film is continuous or closed. In one example, the plasma treatment process can be performed after about every 2 deposition cycles, about every 4 deposition cycles, about every 6 deposition cycles, about every 10 deposition cycles, about every 25 deposition cycles, about every 50 deposition cycles, about every 100 deposition cycles, about every 200 deposition cycles, about every 300 deposition cycles, about every 400 deposition cycles, about every 500 deposition cycles, about every 1000 deposition cycles, or any other suitable number of deposition cycles. In some examples, at least 2 consecutive deposition cycles are performed without the plasma treatment process. In one example, at least 5 or 10 deposition cycles are performed without the plasma treatment process. In some embodiments, the plasma treatment process can be performed before any deposition is performed; that is, before any deposition cycle is performed.

[0070] In one example, the plasma treatment process can be performed in the same reaction chamber or reactor as the deposition process 100. In some examples, the plasma treatment process can be performed in a different reaction chamber or reactor than the deposition process 100.

[0071] In some embodiments, the plasma is formed in a reactor. In some embodiments, the plasma can be formed in situ on top of or immediately adjacent to the substrate. In other embodiments, the plasma is formed upstream of the reaction chamber in a remote plasma generator, and the plasma products are directed to the reaction chamber to contact the substrate. As will be appreciated by those skilled in the art, in the case of a remote plasma, the path to the substrate can be optimized to maximize electrically neutral species and minimize ion survival before reaching the substrate.

[0072] In some embodiments, multiple deposition cycles may be used to deposit the Al and N and / or O containing material, and the plasma treatment may be applied one or more times, including, for example, before deposition, after each deposition cycle, at predetermined intervals during deposition, or after a desired thickness of the Al and N and / or O containing material has been deposited.

[0073] In one example, the plasma treatment process includes exposing the substrate to a direct plasma. In some embodiments, the plasma treatment process includes exposing the substrate to a remote plasma. In one example, the plasma treatment process includes exposing the substrate to excited species or atomic species produced in a plasma discharge, but does not include a large amount of ions (if any). In some examples, the plasma may include oxygen. In one example, the plasma may include nitrogen. Although referred to as a plasma treatment process, in some embodiments, reactive oxygen species that do not include plasma, such as ozone, may be used. In some embodiments, the plasma may include hydrogen.

[0074] In one example, the substrate is exposed to a reactant comprising oxygen plasma using a pretreatment process or a plasma treatment process. O2 can be provided as a source gas, for example, at about 1 to about 2000 sccm, more preferably about 5 to about 1000 sccm, and most preferably about 50 to about 500 sccm. In some examples, O2 can be provided at about 300 sccm.

[0075] In one example, the substrate is exposed to a reactant comprising nitrogen plasma using a pretreatment process or a plasma treatment process. For example, N2 can be provided as a source gas at about 1 to about 5000 sccm, more preferably about 5 to about 2000 sccm, and most preferably about 50 to about 500 sccm. In some embodiments, N2 can be provided at about 300 sccm.

[0076] In one example, the substrate is exposed to a reactant comprising hydrogen plasma using a pretreatment process or a plasma treatment process. In some embodiments, H2 can be provided as a source gas, for example, at about 1 to about 2000 sccm, more preferably about 5 to about 1000 sccm, and most preferably about 10 to about 100 sccm. In some examples, H2 can be provided at about 50 sccm. Similar conditions can be used for other types of plasmas.

[0077] In one example, the plasma treatment process may include exposing the substrate to the reactant at a treatment temperature. In some embodiments, the treatment temperature may be greater than about 20°C. In one example, the treatment temperature may be between about 20°C and about 500°C, more preferably between about 50°C and about 450°C, and more preferably between about 150°C and about 400°C. In some examples, the treatment temperature may be substantially the same as the deposition temperature and / or the pretreatment temperature. In one example, the treatment temperature may be different from the deposition temperature and / or the pretreatment temperature.

[0078] In some embodiments, the plasma may be generated at a power of less than about 2500 W, such as about 1 to about 1000 W, about 1 to about 500 W, or about 1 to about 200 W or less. In one example, the plasma may be generated at a power of 50 W. In some examples, the plasma may be generated at a power of 100 W.

[0079] In an example, the plasma is provided for less than about 200 seconds, such as about 180 seconds or less, about 60 seconds or less, about 30 seconds or less, about 10 seconds or less, or about 3 seconds or less.

[0080] In some embodiments, the plasma treatment process 170 may be substantially the same as the pre-treatment process 110 .

[0081] Although the Al and N and / or O-containing material deposition cycle is shown to begin with contacting the substrate surface with a first vapor-phase precursor containing Al, in other embodiments, the deposition cycle begins with contacting the substrate surface with a second vapor-phase precursor containing nitrogen. Those skilled in the art will appreciate that, in a deposition cycle, contacting the substrate surface with the first vapor-phase precursor containing Al and the second vapor-phase precursor containing nitrogen are interchangeable.

[0082] In one example, the substrate is moved so that different reactants contact the substrate surface alternately and sequentially in a desired order for a desired time. In some examples, removal steps 130 and 150 are not performed. In one example, no reactants can be removed from various parts of the chamber. In some embodiments, the substrate is moved from a portion of the chamber containing the first precursor to another portion of the chamber containing the second reactant. In one example, the substrate is moved from a first reaction chamber to a different second reaction chamber.

[0083] A skilled artisan can determine the optimal reactant evaporation temperature based on the properties of the selected precursors. A skilled artisan can determine the optimal reactant contact time by routine experimentation based on the properties of the selected precursors and the desired properties of the deposited Al and N and / or O-containing material.

[0084] The growth rate of the material containing Al and N and / or O will vary depending on the reaction conditions. In some examples, the deposited material containing Al and N and / or O includes a thin film. In one example, the deposited material containing Al and N and / or O includes AlN and Al2O3.

[0085] In some embodiments, the deposited material containing Al and N and / or O is AlN. In one example, the deposited material containing Al and N and / or O is Al2O3. In one example, the deposited material containing Al and N and / or O is non-stoichiometric AlxOy. In some embodiments, a material containing Al and N and / or O consisting essentially of Al and N and / or O is formed. In some embodiments, additional reactants can be used to incorporate other materials into the film or contribute to the film, such as oxygen to form aluminum oxynitride. In one example, in the case where additional non-metallic elements other than nitrogen are desired, the ALD process for forming a material containing Al and N and / or O can include phases other than the initial Al and N and / or O phases. For example, they can include an oxidation phase requiring metal aluminum oxynitride. In the oxidation phase, oxygen or an oxygen-containing precursor is provided in the reaction chamber and is brought into contact with the substrate surface. The oxygen phase can be part of one or more deposition cycles. In some embodiments, a second metal phase can be provided in one or more deposition cycles. The oxidation phase or other desired phase may follow the Al phase or the N phase, but in either case, in some embodiments, it is desirable to remove excess oxygen (or other reactants) and any reaction byproducts from the reaction space before proceeding to the next phase. In one example, additional phases, such as oxygen or additional metal phases, may be provided after the final deposition cycle or intermittently during the deposition process.

[0086] In one example, the deposition of the material containing Al and N and / or O on the first surface of the substrate has a selectivity of at least about 90%, at least about 95%, at least about 96%, 97%, 98%, or 99% or more relative to the second surface of the substrate. In some examples, the deposition of the material containing Al and N and / or O occurs only on the first surface and not on the second surface. In one example, the deposition on the first surface of the substrate has a selectivity of at least about 80% relative to the second surface of the substrate, which may be sufficient selectivity for some specific applications. In some embodiments, the deposition on the first surface of the substrate has a selectivity of at least about 50% relative to the second surface of the substrate, which may be sufficient selectivity for some specific applications. In one example, the deposition on the first surface of the substrate is at least about 1%, at least about 2.5%, at least about 5%, at least about 10%, at least about 15%, at least about 20%, at least about 25%, at least about 30%, or at least about 40% relative to the second surface of the substrate, all of which may be sufficient selectivity for some specific applications.

[0087] In some examples, the ratio of the material containing Al and N and / or O deposited on the first surface of the substrate relative to the second surface of the substrate may be greater than or equal to about 10:1, greater than or equal to about 20:1, or greater than or equal to about 40:1. In one example, when the thickness of the material containing Al and N and / or O deposited on the first surface of the substrate is greater than about 5 nm, the ratio of the material containing Al and N and / or O deposited on the first surface of the substrate relative to the second surface of the substrate may be greater than or equal to about 10:1, greater than or equal to about 20:1, or greater than or equal to about 40:1. In some embodiments, when the thickness of the material containing Al and N and / or O deposited on the first surface is greater than about 2.5 nm, the ratio of the material containing Al and N and / or O deposited on the first surface of the substrate relative to the second surface of the substrate may be greater than or equal to about 10:1, greater than or equal to about 20:1, or greater than or equal to about 40:1. In one example, when the thickness of the material containing Al, N and / or O deposited on the first surface of the substrate is greater than about 1 nm, the ratio of the material containing Al, N and / or O deposited on the first surface of the substrate relative to the second surface of the substrate may be greater than or equal to about 10:1, greater than or equal to about 20:1, or greater than or equal to about 40:1.

[0088] In some examples, when the Al- and N- and / or O-containing material deposition process includes about 0 to about 25 deposition cycles, about 0 to about 50 deposition cycles, about 0 to about 100 deposition cycles, or about 0 to about 150 deposition cycles, about 0 to about 300 deposition cycles, about 0 to about 500 deposition cycles, about 0 to about 700 deposition cycles, or about 0 to about 1000 deposition cycles, the ratio of the Al- and N- and / or O-containing material deposited on the first surface of the substrate relative to the second surface of the substrate may be greater than or equal to about 10:1, greater than or equal to about 20:1, or greater than or equal to about 40:1. In one example, when the Al- and N- and / or O-containing material deposition process includes about 0 to about 25 deposition cycles, about 0 to about 50 deposition cycles, about 0 to about 100 deposition cycles, or about 0 to about 150 deposition cycles, about 0 to about 300 deposition cycles, about 0 to about 500 deposition cycles, about 0 to about 700 deposition cycles, or about 0 to about 1000 deposition cycles, less than about 0.1 nm of the Al- and N- and / or O-containing material is deposited on the second surface of the substrate.

[0089] In some embodiments, the material containing Al and N and / or O has an etching selectivity relative to SiO2, that is, the etching rate of the material containing Al and N and / or O is less than the etching rate of SiO2, for example in diluted HF. In one example, the material containing Al and N and / or O has a wet etching rate (WER) of less than 1 / 5, and the thermal oxide removal rate with diluted HF (0.5%) is about 2-3nm / min. In some examples, the wet etching rate of the material containing Al and N and / or O relative to the wet etching rate of thermal silicon oxide (SiO2, TOX) is less than about 0.2 in 0.5% dHF. In one example, in 0.5% dHF, the wet etching rate of the material containing Al and N and / or O relative to the wet etching rate of TOX is less than about 0.1. In some embodiments, in 0.5% dHF, the wet etching rate of the material containing Al and N and / or O relative to the wet etching rate of TOX is less than about 0.05.

[0090] Reference now Figure 2 In some embodiments, a substrate comprising a first surface and a second surface is provided, and AlO is selectively deposited on the first surface of the substrate by a cyclic deposition process 200 comprising at least one cycle, the cycle comprising: at step 220, contacting the substrate with an Al-containing precursor; at step 230, removing excess precursor and reaction byproducts, if any, from the surface; at step 240, contacting the substrate with a vapor-phase precursor comprising oxygen; at step 250, removing excess oxygen species and any byproducts from the surface; and optionally, at step 260, repeating the contacting and removing steps until an aluminum oxide film of a desired thickness is formed.

[0091] Although the aluminum oxide deposition cycle is illustrated as beginning with contacting the substrate with TMA, in other embodiments, the deposition cycle begins with contacting the substrate with a gas-phase oxygen species.

[0092] In one example, before starting the deposition process, one or more surfaces of the substrate may be subjected to a pre-treatment process. Figure 2 In the embodiment of the present invention, this is represented by step 210, where the substrate can be exposed to a pretreatment reactant, such as a plasma, before depositing the Al and O-containing material. In some examples, this pretreatment process can be similar to that described above with reference to Figure 1 The pre-processing process 110 described is essentially the same.

[0093] Still refer to Figure 2 At step 220, the substrate is contacted with a first precursor comprising Al. In one example, the first precursor is introduced into the reaction chamber in the form of a gas phase pulse and contacted with the substrate surface. The conditions are preferably selected so that no more than about one monolayer of the precursor is adsorbed on the substrate surface in a self-limiting manner. However, in some embodiments, the conditions can be selected so that more than one monolayer of the precursor can be formed.

[0094] The first precursor pulse is preferably provided in gaseous form. For purposes of this specification, a first precursor gas is considered "volatile" if it exhibits sufficient vapor pressure under process conditions to deliver the substance to the workpiece in sufficient concentration to saturate the exposed surface.

[0095] In some embodiments, the first precursor contacts the substrate for about 0.01 second to about 60 seconds, about 0.02 second to about 30 seconds, about 0.025 second to about 20 seconds, about 0.05 second to about 5.0 seconds, about 0.05 second to about 2.0 seconds, or about 0.1 second to about 1.0 second.

[0096] The first precursor used in an ALD type process can be a solid, liquid or gaseous material under standard conditions (room temperature and atmospheric pressure) as long as the first precursor is in the gas phase before being introduced into the reaction chamber and contacting the substrate surface.

[0097] In step 230, excessive first precursor and reaction byproduct (if any) are removed from the substrate surface, for example, by purging with an inert gas such as nitrogen or argon pulse.Purge reaction chamber means removing gaseous phase precursor and / or gaseous phase byproduct from reaction chamber, for example, by evacuating reaction chamber with a vacuum pump and / or by replacing the gas in the reactor with an inert gas such as argon or nitrogen.Typical purge time is about 0.05 to 20 seconds, more preferably about 1 to 10 seconds, and even more preferably about 1 to 2 seconds.However, if necessary, other purge times can be used, for example, when depositing layers on structures of extremely high aspect ratios or other structures that need to have complex surface morphology.Skilled technicians can easily determine suitable purge time according to specific circumstances.

[0098] However, in other embodiments, removing excess first precursor and reaction byproducts (if any) can include moving the substrate so that the first precursor no longer contacts the substrate. In one example, no precursor can be removed from various portions of the chamber. In some examples, the substrate is moved from one portion of the chamber containing the first precursor to another portion of the chamber containing the second precursor or no precursor at all. In one example, the substrate is moved from a first reaction chamber to a different second reaction chamber.

[0099] At step 240, the substrate is contacted with a second vapor-phase precursor comprising oxygen (O). In some embodiments, the second precursor is pulsed into the chamber where it reacts with the first precursor bound to the first surface of the substrate. The reaction typically forms up to about a monolayer of Al and O-containing material on the substrate. However, in some embodiments, more than one molecular layer of Al and O-containing material is formed on the substrate.

[0100] In some embodiments, the second precursor may include plasma or free radicals. While those skilled in the art will recognize that any number of suitable second precursors may be used, suitable second precursors include oxygen-containing compounds that react advantageously with ligands of a previously or subsequently deposited first precursor. Thus, the selection of a suitable second precursor may depend on the particular first precursor used and the nature of the ligands in the first precursor.

[0101] In one example, the second precursor contacts the substrate for about 0.01 second to about 60 seconds, about 0.02 second to about 30 seconds, about 0.025 second to about 20 seconds, about 0.05 second to about 5.0 seconds, about 0.05 second to about 2.0 seconds or about 0.1 second to about 1.0 second. However, depending on the reactor type, substrate type and surface area thereof, the second precursor contact time can even be higher than 10 seconds. In some embodiments, the contact time can be the order of several minutes. Technicians can easily determine the optimal contact time according to the specific circumstances.

[0102] The concentration of the second precursor in the reaction chamber may be about 0.01 vol% to about 99.0 vol%. And the second precursor may flow through the reaction chamber at a rate of about 1 standard cm3 / min to about 4000 standard cm3 / min.

[0103] At step 250, excess second precursor and gaseous byproducts of the surface reaction, if any, are removed from the substrate, as described above with respect to step 130. In some examples, excess precursor and reaction byproducts are preferably removed with the aid of an inert gas.

[0104] At step 260, the contacting and removing steps may optionally be repeated until a desired thickness of the Al and O-containing material has been formed on the first surface of the substrate, leaving no more than about one molecular monolayer per cycle. In some cases, it may be desirable to achieve at least partial decomposition of at least one of the various precursors. Thus, in some embodiments, conditions may be selected such that more than one molecular layer of the Al and O-containing material is formed on the substrate in each deposition cycle.

[0105] The Al- and O-containing material ALD process of the present disclosure may include one or more cycles. Some embodiments include repeating at least about 5 cycles, at least about 10 cycles, or at least about 50 cycles, or at least about 100 cycles, at least about 150 cycles, or at least about 200 cycles, or at least about 350 cycles, at least about 500 cycles, or at least about 650 cycles, or at least about 800 cycles, at least about 950 cycles, or at least about 1000 cycles. In some embodiments, no more than 1000 cycles are performed to form a film of desired thickness.

[0106] In one example, the substrate surface and / or the Al and O containing material may optionally be subjected to a plasma treatment process.

[0107] In some embodiments, the pretreatment process can enhance the selectivity of the selective deposition process 200. In one example, the pretreatment process can enhance the selectivity of the subsequent selective deposition process by more than about 2 times, more than about 5 times, or more than about 10 times. In some examples, the pretreatment process can enhance the deposition of AlO on one surface relative to one or more different surfaces before starting the deposition process. In one example, the pretreatment process can inhibit the deposition of AlO on one surface relative to one or more different surfaces before starting the deposition process. In some embodiments, the pretreatment process can inhibit the deposition of Al and O-containing materials on one surface relative to one or more different surfaces before starting the deposition process 200.

[0108] In one example, the substrate surface and / or the aluminum oxide film may be optionally subjected to a plasma treatment process. In some examples, the pretreatment process may be performed in the same reaction chamber or reactor as the subsequent deposition process 100. In one example, the pretreatment process may be performed in a different reaction chamber or reactor than the subsequent deposition process 100.

[0109] exist Figure 2 In some embodiments, the plasma treatment process may be similar to that described above with reference to Figure 1 The plasma treatment process 170 described is essentially the same.

[0110] In one example, the plasma treatment process 270 can be substantially the same as the pretreatment step 210. In some examples, the plasma treatment process can be performed after more than one deposition cycle has been performed. In one example, the plasma treatment process can be performed before the deposited aluminum oxide film is continuous or closed. In some embodiments, the plasma treatment process can be performed after more than about 10 deposition cycles, more than about 20 deposition cycles, or more than about 50 deposition cycles. In one example, the plasma treatment process can be performed in the same reaction chamber or reactor as the deposition process 200. In some examples, the plasma treatment process can be performed in a different reaction chamber or reactor than the deposition process 200.

[0111] In one example, a substrate including a first surface and a second dielectric surface is provided, and a material containing Al and O is selectively deposited on the first surface of the substrate by a cyclic deposition process, the cyclic deposition process including at least one cycle including contacting the substrate with a gas phase first precursor and a gas phase second precursor alternately and sequentially. In some embodiments, the first precursor may include Al and the second precursor may include O. In one example, the first precursor may include TMA and the second precursor may include H2O.

[0112] In some examples, a substrate including a first surface and a second dielectric surface is provided, and Al2O3 is selectively deposited on the first surface of the substrate by a cyclic deposition process, the cyclic deposition process including at least one cycle including contacting the substrate with a gas phase first precursor and a gas phase second precursor alternately and sequentially. In one example, the first precursor may include Al and the second precursor may include O.

[0113] In some embodiments, the first precursor may include TMA and the second precursor may include H2O.

[0114] In one example, a substrate is provided, and aluminum oxide is deposited on at least a portion of the substrate by a cyclic deposition process, the cyclic deposition process comprising at least one cycle comprising alternatingly and sequentially contacting the substrate with a gas-phase first precursor and a gas-phase second precursor, and the first precursor may include an aluminum-containing precursor (e.g., TMA), and the second precursor may include an oxygen reactant (e.g., H2O, O3, H2O2, etc.).

[0115] In some embodiments, prior to deposition, the substrate may be subjected to a pretreatment process. In some examples, the pretreatment process may enhance the selectivity of the selective deposition process. In one example, prior to initiating the deposition process, the pretreatment process may enhance the deposition of aluminum oxide on one surface relative to one or more different surfaces. In some embodiments, prior to initiating the deposition process, the pretreatment process may inhibit the deposition of aluminum oxide on one surface relative to one or more different surfaces. In one example, the pretreatment process may include exposing the substrate to a pretreatment reactant, such as a plasma, prior to depositing the aluminum oxide.

[0116] In some examples, the substrate surface and / or the aluminum oxide film may optionally be subjected to a plasma treatment process. In one example, the plasma treatment process may be similar to that described above with respect to Figure 1 and Figure 2 The plasma treatment processes 170 and 270 described are substantially the same.

[0117] In some embodiments, the plasma treatment process may be substantially the same as the pretreatment process. In one example, the plasma treatment process may be performed after more than one deposition cycle has been performed. In some examples, the plasma treatment process may be performed before the deposited aluminum oxide film is continuous or closed. In one example, the plasma treatment process may be performed after less than about 10 deposition cycles, less than about 20 deposition cycles, or less than about 50 deposition cycles. In some embodiments, the plasma treatment process may be performed in the same reaction chamber or reactor as the deposition process. In one example, the plasma treatment process may be performed in a different reaction chamber or reactor than the deposition process.

[0118] refer to Figure 3A And according to some embodiments, a material containing Al and N and / or O is selectively formed on a first surface relative to a different second surface of a substrate by a process 300 including at least one super cycle 301, the substrate including a first surface and a different second surface, the cycle including: in step 320, selectively depositing the material containing Al and N and / or O on the first surface of the substrate relative to the different second surface, etching the deposited material containing Al and N and / or O so that substantially all of the deposited material containing Al and N and / or O is removed from the second surface, and in step 330, not all of the deposited material containing Al and N and / or O is removed from the first surface, optionally repeating the selective deposition and etching steps in step 340 until a desired thickness of the material containing Al and N and / or O has been formed on the first surface of the substrate relative to the different second surface.

[0119] In some examples, at the start of super cycle 301, one or more surfaces of the substrate may be subjected to a treatment process in step 310 (see Figure 3B ) is subjected to a pretreatment process. In one example, the pretreatment process can enhance the selectivity of the selective deposition process step 320. In some embodiments, before the selective deposition step 320, the pretreatment process can enhance the deposition of the material containing Al and N and / or O on one surface relative to one or more different surfaces. In one example, before the selective deposition step 320, the pretreatment process can inhibit the deposition of the material containing Al and N and / or O on one surface relative to one or more different surfaces.

[0120] In one example, according to Figure 1 and / or Figure 2 The method described herein deposits a material containing Al and N and / or O. In one example, the selective deposition of the material containing Al and N and / or O can be obtained from the Figure 1 and / or Figure 2The method described begins, where the deposited Al and N and / or O containing material may subsequently be modified as described below, for example by oxidation in step 350 and / or by exposure to one or more cyclic deposition-etch-oxidation steps (e.g., in steps 320, 330, and 350, respectively), and / or by exposure to a pretreatment (e.g., in step 310).

[0121] exist Figure 3A In the embodiment of the present invention, this is represented by step 310 of super cycle 301, where the substrate may be exposed to a pre-treatment reactant, such as a plasma, prior to selectively depositing a material containing Al and N and / or O at step 320.

[0122] In some examples, the preprocessing process can be similar to that described in the present invention. Figure 1 and Figure 2 The pretreatment process 110 and / or 210 are the same. In one example, the pretreatment process may include exposing the substrate to a pretreatment reactant. In some embodiments, the pretreatment reactant may include hydrogen. In one example, the pretreatment reactant includes hydrogen radicals, atomic hydrogen, hydrogen plasma, or a combination thereof. In some examples, the pretreatment reactant may include a plasma generated by a gas containing H2.

[0123] In some embodiments, the plasma is formed in a reactor. In some embodiments, the plasma can be formed in situ on top of or immediately adjacent to the substrate. In other embodiments, the plasma is formed upstream of the reaction chamber in a remote plasma generator, and the plasma products are directed to the reaction chamber to contact the substrate. As will be appreciated by those skilled in the art, in the case of a remote plasma, the path to the substrate can be optimized to maximize electrically neutral species and minimize ion survival before reaching the substrate.

[0124] In one example, the treated substrate is not exposed to the surrounding environment after the pretreatment process 310 and before starting the selective deposition step 320. In some embodiments, the treated substrate is not exposed to air after the pretreatment process 310 and before starting the selective deposition process at step 320.

[0125] In one example, the pretreatment process can be used to enhance the selectivity of a subsequent selective deposition process. In some examples, the pretreatment process can enhance the selective deposition of a material containing Al and N and / or O on a first surface (e.g., the first and second surfaces described herein) relative to a different second surface. In one example, the pretreatment process can enhance the selectivity of a subsequent selective deposition process by more than about 2 times, more than about 5 times, or more than about 10 times.

[0126] In some embodiments, the pretreatment process 310 may be performed in the same reaction chamber or reactor as the subsequent selective deposition step 320. In one example, the pretreatment process 310 may be performed in a different reaction chamber or reactor than the subsequent selective deposition step 320.

[0127] Reference again Figure 3A , at step 320, a material containing Al and N and / or O is selectively deposited on the first surface of the substrate relative to the second surface. In some examples, selectively depositing the material containing Al and N and / or O at step 320 may include a selective deposition process including one or more deposition sub-cycles including alternating and sequentially contacting the substrate with a first vapor-phase aluminum precursor and one or more other vapor-phase precursors containing N and / or O. In an example, the deposition sub-cycles may be repeated 1 to 1000 times, 1 to 500 times, 1 to 300 times, 1 to 200 times, 1 to 50 times, 1 to 30 times, or 1 to 10 times.

[0128] In some embodiments, selectively depositing the material containing Al and N and / or O at step 320 may include one or more deposition sub-cycles. Some embodiments include repeating at least about 5 sub-cycles, at least about 10 sub-cycles, at least about 50 sub-cycles, at least about 100 sub-cycles, at least about 150 sub-cycles, at least about 200 sub-cycles, at least about 300 sub-cycles, at least about 500 sub-cycles, or at least about 1000 sub-cycles. In one example, the selective deposition sub-cycles may be repeated until the selective deposition sub-cycles are no longer selective. In some examples, the selective deposition sub-cycles may be repeated until the selective deposition sub-cycles are no longer significantly selective. In one example, the selective deposition sub-cycles may be repeated until the selective deposition sub-cycles have lost a substantial amount of selectivity. In some embodiments, the selective deposition sub-cycle can be repeated until the selective deposition sub-cycle no longer achieves the desired level of selectivity, for example, until the selective deposition sub-cycle no longer achieves about 50% selectivity, about 40% selectivity, about 30% selectivity, about 20% selectivity, about 10% selectivity, about 5% selectivity, about 2% selectivity, about 1% selectivity, or less.

[0129] That is, in some embodiments, selectively depositing the material containing Al and N and / or O at step 320 may include repeating a selective deposition sub-cycle, such as an ALD deposition cycle described herein, until the sub-cycle no longer selectively deposits the material containing Al and N and / or O on the first surface of the substrate relative to the second surface. In some examples, selectively depositing the material containing Al and N and / or O at step 320 may include repeating a selective deposition sub-cycle, such as an ALD deposition cycle described herein, until the selectivity of the sub-cycle drops below a predetermined selectivity. For example, in some embodiments, selectively depositing the material containing Al and N and / or O at step 320 may include repeating a selective deposition sub-cycle until the selective deposition sub-cycle has a selectivity of less than about 50%, less than about 25%, less than about 15%, less than about 10%, less than about 5%, less than about 2%, less than about 1%, or less.

[0130] After selectively depositing the Al and N and / or O containing material at step 320, the deposited Al and N and / or O containing material is etched at step 330, for example, by subjecting the Al and N and / or O containing material to a vapor phase etching process. In one example, the etching process removes substantially all of the deposited Al and N and / or O containing material from the second surface of the substrate, and does not remove substantially all of the deposited Al and N and / or O containing material from the first surface of the substrate. In some embodiments, the etching process may remove the same or similar amounts or thicknesses of Al and N and / or O containing material from the first and second surfaces of the substrate, but because the Al and N and / or O containing material has been selectively deposited on the first surface relative to the second surface at step 320, at least some thickness of the Al and N and / or O containing material remains on the first surface of the substrate at step 330, while substantially all or all of any Al and N and / or O containing material that has been deposited on the second surface of the substrate is removed by the etching process.

[0131] Reference now Figure 3C In some embodiments, etching the deposited Al and N and / or O containing material at step 330 may include subjecting the deposited Al and N and / or O containing material to a vapor phase etching process. In some embodiments, the vapor phase etching process may be a cyclic vapor phase etching process (step 336).

[0132] In some embodiments, the vapor phase etching process may include an atomic layer etching (ALE) process.

[0133] In one example, the etching process of step 330 may include an ALE process, which includes one or more etching sub-cycles, which include: contacting the substrate with a first gas-phase etching reactant (e.g., step 332); removing excess first etching reactant and reaction byproducts (if any) from the substrate (e.g., step 333); contacting the substrate with a second gas-phase etching reactant (e.g., step 334); removing excess second etching reactant and reaction byproducts (if any) from the substrate (e.g., step 333); and optionally repeating the contacting and removing steps to etch the deposited Al- and N- and / or O-containing material to a desired extent, for example, until the deposited Al- and N- and / or O-containing material is substantially completely removed from the second surface of the substrate.

[0134] In some examples, the etching process of step 330 may include an ALE process, which includes one or more etching sub-cycles, which include: contacting the substrate with a first gas-phase halide etching reactant, such as HF, CCl4, BCl3, CF4, hacac, NF3, hexafluoroacetylacetone (hhfac) and / or trifluoroacetylacetonate (e.g., step 332); removing excess first etching reactant and reaction byproducts (if any) from the substrate (e.g., step 333); contacting the substrate with a second gas-phase etching reactant, such as Al (e.g., step 334); removing excess second etching reactant and reaction byproducts (if any) from the substrate (e.g., step 333); and optionally repeating the contacting and removing steps to etch the deposited Al- and N- and / or O-containing material to a desired extent, for example until the deposited Al- and N- and / or O-containing material is substantially completely removed from the second surface of the substrate.

[0135] In one example, a sub-monolayer or more of material can be removed from a substrate by an atomic layer etching (ALE) process, which includes contacting the substrate surface with at least one gas phase reactant in a reaction space. In some embodiments, one or more gas phase halide reactants are used. The halide reactant can be a metal halide, a non-metal halide, a semi-metal halide, a semi-metal / non-metal halide oxide, an organic halide and / or an organic (oxygen) halide. For example, the gas phase halide reactant can include any one of CCl4, NF3, hexafluoroacetylacetone and / or trifluoroacetylacetonate.

[0136] In one example, surface contaminants, such as B or C contaminants, may be removed from the substrate surface.

[0137] In some embodiments, the ALE process includes contacting the substrate surface with at least the first and second gas phase reactants alternately in the reaction space. In some examples, one or more gas phase reactants are halide reactants. One or more etching cycles or sub-cycles can be provided in the ALE process as part of a selective deposition process or a selective deposition super cycle. In one example, the etching cycle includes exposing the substrate alternately to two different reactants. In some embodiments, the etching cycle includes exposing the substrate to three different reactants. In one example, the etching cycle includes exposing the substrate to four different reactants. In some examples, the etching cycle includes exposing the substrate to more than four reactants. In one example, the reactant exposure is continuous. Each reactant exposure can be separated by purging the reaction space, or by evacuating the reaction chamber to remove reaction byproducts and excess reactants.

[0138] In some embodiments, the substrate to be etched is exposed to one or more reactants selected from halides, oxygen compounds, oxygen scavengers, halide exchange drivers, ligand exchangers, and metal organic or inorganic reactants. The oxygen compound may include, for example, H2O, O2, or O3. The oxygen scavenger or halide exchange driver may include, for example, ChyClx, CCl4. In one example, the oxygen scavenger or halide exchange driver is a halide described herein, including a non-metallic or semi-metallic halide. The halide exchange driver may be NF3, hexafluoroacetylacetone, WF6, and / or trifluoroacetylacetonate.

[0139] In some examples, the ligand exchanger or metal or inorganic reactant may include, for example, TMA, Hacac, or TMA / Sn(acac) 2. In one example, the ligand exchanger may be a halide as described herein, including a non-metal or semi-metal halide.

[0140] In some embodiments, the etching cycle (step 336) can include a saturated self-limiting adsorption step in which the substrate is contacted with at least one gas phase reactant, such as a halide reactant. For example, the substrate can be contacted with a first gas phase reactant (step 332) followed by a second exposure step in which the substrate is contacted with a second gas phase reactant (step 334). In the first adsorption step, the first reactant adsorbs to the material to be etched on the substrate surface in a self-limiting manner. The second exposure step then results in the formation of volatile byproducts that include atoms of the adsorbate, atoms of the second precursor, and some atoms from the etched surface. In this way, the etching of the desired material on the substrate surface can be carefully controlled.

[0141] In one example, the reaction is not self-limiting. However, controlled etching can be achieved by supplying controlled doses of one or more reactants.

[0142] In some embodiments, gas phase reactions are avoided by alternately and sequentially supplying precursors to the reaction chamber. Gas phase reactants are separated from each other in the reaction chamber, for example, by removing excess reactants and / or reaction byproducts from the reaction chamber between reactant pulses (step 333). With the aid of purge gas and / or vacuum, reactants can be removed from the vicinity of the substrate surface. In some examples, by purging, for example, purging with an inert gas, excess reactants and / or reactant byproducts are removed from the reaction space. Due to the separation of reactants and the self-limiting nature of the reaction, less than a monolayer of material is usually removed in each ALE etching cycle. However, in some embodiments, more than one monolayer can be removed in each cycle. In one example, the pulses of reactants can overlap partially or completely. For example, in some embodiments, a reactant can flow continuously into the reaction space, and one or more additional reactants are provided intermittently at desired intervals.

[0143] In some embodiments, the ALE method disclosed herein is a thermal etching process, as opposed to a plasma etching process. Therefore, no plasma reactants are used in these thermal valve etching cycles. Although referred to as a "thermal" ALE process to distinguish between processes using plasma reactants, in some embodiments, the ALE reaction may have zero activation energy and therefore does not require any additional thermal energy. Therefore, these reactions may also be referred to as chemical etching processes. In some cases, thermal ALE methods may be more ideal than plasma ALE methods because thermal ALE methods cause less damage to the underlying substrate. In addition, thermal ALE methods may allow isotropic etching of non-line-of-sight (NLOS) features.

[0144] However, in some embodiments, the etching process may include an ALE process including a plasma. In one example, the ALE process may include contacting the deposited Al and N and / or O-containing material with at least one gas phase etching reactant. In some examples, the etching process may be a dry etching process, such as a reactive ion etching process. In one example, the dry etching process may be a thermal dry etching process. In some embodiments, the dry etching process may include using a plasma.

[0145] In one example, the etching process of step 330 may include an ALE process including one or more etching sub-cycles including alternating and sequentially contacting the deposited Al- and N- and / or O-containing material with a first vapor-phase etching reactant (at step 332) and a second vapor-phase etching reactant (at step 334). In some examples, the etching sub-cycle may be repeated 1 to 1000 times, 1 to 500 times, 1 to 300 times, 1 to 200 times, 1 to 150 times, 1 to 100 times, or 1 to 50 times.

[0146] In one example, the etching sub-cycle can be repeated one or more times. Some embodiments include repeating at least about 5 sub-cycles, at least about 10 sub-cycles, at least about 50 sub-cycles, at least about 100 sub-cycles, at least about 150 sub-cycles, at least about 200 sub-cycles, at least about 300 sub-cycles, at least about 500 sub-cycles, or at least about 1000 sub-cycles. In some embodiments, the etching sub-cycle can be repeated until substantially all deposited Al and N and / or O-containing materials are removed from the second surface of the substrate, rather than all deposited Al and N and / or O-containing materials being removed from the first surface of the substrate.

[0147] According to some embodiments, the etching sub-cycle may be performed in a temperature range of about 20° C. to about 1200° C., about 50° C. to about 800° C., about 75° C. to about 600° C., about 300° C. to about 500° C., or about 350° C. to about 450° C. In one example, the temperature is greater than about 20, 50, or 100° C., but less than about 1000, 800, 600, or 500° C. In some examples, the cycle is performed at a temperature between about 200° C. and 450° C.

[0148] The pressure in the reaction chamber is typically about 1.0 Torr to about 760 Torr, or about 0.001 Torr to about 100 Torr. However, in some cases, the pressure will be higher or lower than this range, which can be determined by a technician in a specific case. In one example, a pressure of less than 2 tons is used.

[0149] In some embodiments, the etching reactant contacts the substrate with the surface to be etched for about 0.01 to about 60 seconds, about 0.05 to about 30 seconds, about 0.05 seconds to about 5.0 seconds, about 0.1 seconds to about 3 seconds, or about 0.2 seconds to about 1.0 seconds. In one example, the etching reactant contacts the substrate surface to be etched for about 0.05 seconds to about 5.0 seconds, about 0.1 seconds to about 3 seconds, or about 0.2 seconds to about 1.0 seconds. In some examples, the contact time can be greater than about 60 seconds. However, depending on the reactor type, the material to be etched and other process conditions, such as surface area and temperature, the etching reactant contact time can even be higher than about 10 seconds. In some embodiments, the contact time can be the magnitude of several minutes. The technician can easily determine the optimal contact time according to the specific circumstances.

[0150] In one example, excessive etching reactants and reaction byproducts (if any) can be removed from the substrate by, for example, purging the reaction chamber with an inert purge gas. In certain embodiments, the reaction chamber can be purged by stopping the flow of the etching reactants while continuing to flow carrier gas or purge gas long enough to diffuse or purge excessive reactants and reactant byproducts from the reaction space. In one example, excessive etching reactants and reaction byproducts are purged with the help of an inert gas such as helium or argon. In some examples, the substrate can be moved to different reaction spaces from the reaction space comprising the second reactant. In certain embodiments, the pulse of the purge gas can be from about 0.1 second to about 10 seconds, about 0.1 second to about 4 seconds or about 0.1 second to about 0.5 second.

[0151] In one example, the first gas phase etching reactant may include a halide. In certain embodiments, the first gas phase etching reactant may include HF, CCl4, BCl3, CF4, hacac, NF3, hexafluoroacetylacetone, trifluoroacetylacetone or NbF5. In one example, the first gas phase etching reactant may not include plasma or stimulated reactants. In some examples, the second gas phase etching reactant may include aluminum. In one example, the second gas phase etching reactant may include one of tri-tert-butylaluminum (TTBA), trimethylaluminum (TMA) or triethylaluminum (TEA). In certain embodiments, the second gas phase etching reactant may be identical to the gas phase precursor of the selective deposition step 320. In one example, the second gas phase etching reactant may include TMA. In some examples, the second gas phase etching reactant may not include plasma or stimulated reactants.

[0152] In one example, the etching step 330 is performed in the same reaction space as the selective deposition step 320. However, in some embodiments, the etching step 330 may be performed in a different reaction space from the selective deposition step 320. In some embodiments, the steps of selectively depositing AlN and / or aluminum oxide and etching the substrate may be optionally repeated at step 340 until a desired thickness of a material containing Al and N and / or O has been formed on the first surface of the substrate relative to the second surface. That is, the super cycle 301 may be optionally repeated until a desired thickness of a material containing Al and N and / or O has been formed on the first surface of the substrate relative to the second surface. In one example, after the etching step 330 and before starting another super cycle 301, the substrate is not exposed to the ambient atmosphere. In some examples, after the etching step 330 and before starting another super cycle 301, the substrate is not exposed to air. In one example, after the etching step 330 and before starting another super cycle 301, the substrate is exposed to the ambient atmosphere. In some examples, after the etching step 330 and before starting another super cycle 301, the substrate is exposed to air.

[0153] In some embodiments, super cycle 301 may include a pre-treatment step 310 and / or an oxidation treatment step 350, although the subject matter is not limited in this regard.

[0154] The first precursor

[0155] Many different first precursors can be used in the selective deposition process described herein as the first precursor in a selective deposition cycle and / or a selective deposition sub-cycle. In one example, the first precursor is an organometallic compound containing aluminum. In some embodiments, the first precursor is an alkyl aluminum compound. In one example, the first precursor does not include any other metal besides aluminum.

[0156] In some examples, the first precursor is a compound having the formula R3A1, wherein R is an alkyl group. Each R can be independently selected from methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl and tert-butyl. Preferably, each R can be independently selected from: methyl, ethyl and tert-butyl. In some embodiments, each R can be independently selected from C1-C4 alkyl.

[0157] In one example, the first precursor includes Me3Al, Et3Al, or tBu3Al. In some embodiments, the first precursor is tri-tert-butylaluminum (TTBA) as described above, and in some embodiments, the first precursor is trimethylaluminum (TMA).

[0158] In one example, the first precursor is not a halide. In some examples, the first precursor may include a halogen in at least one ligand, but not in all ligands. In one example, the first precursor includes a chlorine ligand and two alkyl ligands. In some embodiments, the first precursor is AlCl3.

[0159] In one example, the first precursor may include hydrogen as at least one ligand, but not all ligands. In some examples, the first precursor may include at least one hydrogen ligand and at least one alkyl ligand.

[0160] In one example, the first precursor does not include nitrogen. In some embodiments, the first precursor does not include silicon. In one example, the first precursor does not include oxygen. In some examples, the first precursor does not include nitrogen, silicon, or oxygen.

[0161] The second precursor

[0162] In one example, the second precursor includes nitrogen hydrogen bonds. In some embodiments, the second precursor is ammonia (NH3). In some embodiments, the second precursor is molecular nitrogen. In one example, the second precursor is a nitrogen-containing plasma, such as a plasma containing nitrogen and hydrogen. In some embodiments, the second precursor includes an activated or excited nitrogen species. In some examples, the second precursor can be provided as a nitrogen-containing gas pulse, which can be a mixture of a nitrogen reactant and an inert gas (e.g., argon).

[0163] Figure 4 A process flow of a self-aligned contact process including a protective layer, capping layer, or etch stop layer of a material including Al and N and / or O according to some embodiments is shown. In one example, a process for forming a self-aligned contact 400 is performed as follows: at step 401, a semiconductor substrate including a first surface 412 and a second (different) surface 414 is provided; at step 402, a protective layer 416 or an etch stop layer including Al and N and / or O, such as AlN, aluminum oxide, or a combination thereof, is selectively deposited on the first surface of the substrate relative to the second surface 414; and at step 403, the protective layer 416 on the second surface 414 is removed, for example, using an etching process (e.g., step 330).

[0164] The semiconductor substrate includes a first surface 412 and a different second surface 414. In some embodiments, the first surface 412 includes a conductive surface. In one example, the first surface 412 includes one or more metal nitrides. In some examples, the first surface 412 may include a surface of a conductive gate and / or a surface of a spacer. For example, in some embodiments, the first surface 412 may include a TiN gate and a SiN spacer. As non-limiting examples, the first surface 412 may include any of the following materials in the non-limiting examples: W, Co, Ru, TiN, Cu, Mo, MoN, TaN and / or Ta.

[0165] The second surface 414 is preferably a dielectric surface. In one example, the dielectric includes SiO2. In some embodiments, the second surface 414 is a virtual contact covering the source / drain region. In one example, the SiO2 virtual contact directly covers the source / drain region. As non-limiting examples, the second surface 414 can include any of the following materials in non-limiting examples: SiO2, SiN, SiGe, SiOxC, SiOxN, HfOx, ZrOx, HfSiOx, SiOxCyNz or ZrSiOx, or a combination thereof, where x=0-2, y=0-2, z=0-2.

[0166] In some examples, the semiconductor substrate is subjected to a standard process by gate polishing. That is, the semiconductor substrate can be subjected to a standard replacement metal gate process flow to form a source, gate, and drain as known in the art. In one example, the semiconductor substrate can be subjected to a chemical mechanical planarization process. In step 402, a protective layer or etch stop layer containing Al and N and / or O is selectively deposited on the first surface of the substrate relative to the second surface. In some embodiments, the protective material containing Al and N and / or O is formed according to the method disclosed above. In step 403, the second surface of the substrate is removed according to the method disclosed above.

[0167] It should be understood that the configuration and / or method described herein are exemplary in nature, and these specific embodiments or examples should not be considered restrictive, because many variations are possible. The specific routine or method described herein can represent one or more of any number of processing strategies. Therefore, the various actions shown can be performed in the order shown, in other orders, or omitted in some cases.

[0168] The headings provided herein, if any, are for convenience only and do not necessarily affect the scope or meaning of the apparatus and methods disclosed herein.

Claims

1. A process for selectively forming aluminum oxide on a first surface of a substrate relative to a second, different surface of the substrate, the process comprising one or more super cycles, the super cycle comprising sub cycles: a) selectively depositing aluminum nitride on a first surface of the substrate relative to a different second surface of the substrate through one or more selective deposition sub-cycles; b) oxidizing at least a portion of the aluminum nitride by one or more oxidizing subcycles; c) etching aluminum oxide or aluminum nitride or a combination thereof by one or more thermal etch sub-cycles, wherein the etchant is an organic halide; and Sub-cycles a), b) or c) or a combination thereof are repeated until a desired thickness of aluminum oxide is formed on the first surface.

2. The process of claim 1, wherein: The aluminum oxide is selectively formed on a first surface of the substrate relative to a second, different surface of the substrate.

3. The process of claim 1, wherein: The one or more super cycles further include exposing the substrate to a pretreatment reactant.

4. The process of claim 3, wherein: Prior to the one or more selective deposition sub-cycles, the substrate is exposed to a pre-treatment reactant.

5. The process of claim 3, wherein: The pretreatment reactant includes a plasma.

6. The process of claim 5, wherein: The plasma is generated from a gas containing H2.

7. The process of claim 1, wherein: The one or more selective deposition sub-cycles include: contacting the substrate with a first vapor precursor comprising aluminum; and The substrate is contacted with a second vapor precursor comprising nitrogen.

8. The process of claim 7, wherein: The first vapor-phase precursor comprising aluminum comprises tri-tert-butylaluminum (TTBA), trimethylaluminum (TMA), or triethylaluminum (TEA).

9. The process of claim 7, wherein: The second gaseous precursor comprising nitrogen comprises NH 3 .

10. The process of claim 1, wherein: The one or more oxidation sub-cycles include: The substrate is contacted with a first vapor precursor comprising oxygen.

11. The process of claim 10, wherein: The first gas-phase precursor containing oxygen includes O3, H2O, H2O2, O2, atomic oxygen, oxygen plasma, native oxide, exposure to the environment or oxygen radicals, or a mixture thereof.

12. The process of claim 1, wherein: The one or more thermal etching sub-cycles include: contacting the substrate with a first vapor phase halide etch reactant; and The substrate is contacted with a second vapor etch reactant comprising aluminum.

13. The process of claim 12, wherein: The first gas-phase halide etching reactant includes HF, CCl4, BCl3, CF4, hacac, NF3, hexafluoroacetylacetone (hhfac), trifluoroacetylacetone, NF3 or NbF5, or a combination thereof.

14. The process of claim 12, wherein: The second vapor-phase etching reactant containing aluminum includes trimethylaluminum (TMA) or triethylaluminum (TEA).

15. The process of claim 12, wherein: The one or more thermal etching sub-cycles are performed at a process temperature of about 25°C-500°C.

16. The process of claim 1, wherein: The first surface is a conductive surface and the different second surface is a dielectric surface.

17. The process of claim 1, wherein: The first surface includes W, Co, Ru, TiN, Cu, Mo, MoN, TaN or Ta, or a combination thereof.

18. The process of claim 1, wherein: The second surface includes SiO2, SiN, SiGe, SiOxC, SiOxN, HfOx, ZrOx, HfSiOx, SiOxCyNz or ZrSiOx, or a combination thereof, wherein x=0-2, y=0-2, z=0-2.

19. The process of claim 1, wherein: The one or more selective deposition sub-cycles are repeated 1 to about 1000 times, and the one or more thermal etching sub-cycles are repeated 1 to about 1000 times.

20. The process of claim 1, wherein: The one or more thermal etch sub-cycles include contacting the substrate with a first vapor phase halide etch reactant comprising hhfac and a second vapor phase etch reactant comprising TMA.

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