Method for depositing a rare earth metal oxide film

Abstract

A substrate processing method for forming a rare earth metal oxide film includes providing a substrate in a reaction chamber and performing a rare earth metal oxide deposition cycle. The rare earth metal oxide deposition cycle includes pulsing a rare earth metal precursor and pulsing a reactant into the reaction chamber.

Description

Technical Field

[0001] Examples of methods for depositing rare earth metal oxide films, structures including rare earth metal oxide films, and substrate processing apparatus for depositing rare earth metal oxide films are described. Background Technology

[0002] Scaling of semiconductor devices has led to significant improvements in the speed and density of integrated circuits. However, more precise deposition techniques and materials are needed to produce semiconductor devices with the desired properties.

[0003] Dipole layers can be used to form gates in certain semiconductor devices. Rare earth metal oxides can possess desirable properties for some dipole layers. However, conventional techniques for depositing rare earth metal oxide films can produce films with relatively high levels of unwanted impurities, which may lead to undesirable electrical properties. Furthermore, conventional techniques for forming rare earth metal oxides can cause undesirable oxidation of the surrounding structure. Therefore, there is a need for techniques for producing rare earth metal oxides, such as those in dipole layers, which have low impurity levels and minimal undesirable oxidation of the surrounding structure.

[0004] Any discussion set forth in this section (including discussions of problems and solutions) is included in this disclosure and is for the purpose of providing background to this disclosure only. Such discussion should not be construed as an admission that any or all information was known at the time of making this invention or otherwise constitutes prior art. Summary of the Invention

[0005] This synopsis is provided to introduce some concepts in a simplified form. These concepts are further described in detail in the following detailed description of exemplary embodiments of this disclosure. This synopsis is not intended to require the identification of key or essential features of the claimed subject matter, nor is it intended to limit the scope of the claimed subject matter.

[0006] The examples described herein provide substrate processing methods, substrate processing apparatus, and structures on substrates. Various examples of substrate processing methods provide the deposition of rare-earth metal oxide films. The exemplary methods disclosed herein provide rare-earth metal oxide films with desired properties, such as low levels of impurities in the film composition; this can be done efficiently, precisely, and accurately using the exemplary methods. The exemplary methods disclosed herein provide techniques for forming rare-earth metal oxides and integrating them into dipole layers, which can be used in gate structures.

[0007] According to various embodiments of the present disclosure, a method for depositing a rare earth metal oxide film is provided, the method comprising: providing a substrate including a surface in a reaction chamber including a reaction space; and performing at least one rare earth metal oxide deposition cycle to deposit a rare earth metal oxide film, wherein the rare earth metal oxide deposition cycle comprises: pulse a rare earth metal precursor to the reaction space, wherein the rare earth metal precursor comprises a rare earth metal, and wherein the rare earth metal precursor comprises a metal-organic precursor; and pulse a reactant to the reaction space, wherein the reactant comprises an oxidant, which comprises one or more of H2O, hydrogen peroxide, or N2O.

[0008] In some embodiments, the rare earth metal precursor includes formamidinium.

[0009] In some embodiments, the rare earth metal precursor comprises tris(N,N'-diisopropylmethylammonium)lanthanum(III).

[0010] In some embodiments, the reactants comprise H2O.

[0011] In some embodiments, the reactants consist of H2O and an optional inert gas / carrier gas.

[0012] In some embodiments, the surface comprises one or more of silicon oxide, silicon nitride, or silicon oxynitride, and a rare earth metal oxide film is deposited on one or more of silicon oxide, silicon nitride, or silicon oxynitride.

[0013] In some embodiments, the method further includes depositing transition metal oxides on a rare earth metal oxide film.

[0014] In some embodiments, the transition metal oxide includes hafnium oxide.

[0015] In some embodiments, the rare earth metal oxide film has a thickness of less than 15 angstroms.

[0016] In some embodiments, the surface includes one or more of silicon oxide, silicon nitride, or silicon oxynitride, a first hafnium oxide film is deposited on one or more of silicon oxide, silicon nitride, and silicon oxynitride, and a rare earth metal oxide film is deposited on the first hafnium oxide film.

[0017] In some embodiments, a second hafnium oxide film is deposited on a rare earth metal oxide film.

[0018] In some embodiments, the reactants comprise H2O.

[0019] In some embodiments, the method further includes repeating rare earth metal oxide deposition cycles at least 20 times, wherein a periodic alumina cycle is performed after between about 10 and 20 rare earth metal deposition cycles, wherein the periodic alumina cycle includes: removing a substrate from a reaction chamber, after removing the substrate from the reaction chamber, pulse an aluminum precursor onto a surface of a reaction space, pulse an oxygen reactant onto a surface of the reaction space to form alumina on the surface of the reaction space, and after pulsed oxygen reactant, reintroducing the substrate into the reaction chamber.

[0020] In some embodiments, the method is a thermal process.

[0021] In some embodiments, the reactants do not include O2 or O3.

[0022] In some embodiments, the method further includes annealing the rare earth metal oxide film, wherein the temperature during annealing is below about 600°C.

[0023] In some embodiments, the rare earth metal oxide film has less than 10 atomic percent carbon atoms.

[0024] In some embodiments, the temperature during the step of performing at least one rare earth metal oxide deposition cycle is between about 150°C and about 350°C, and the pressure during the step of performing at least one rare earth metal oxide deposition cycle is between about 0.5 Torr and about 10 Torr.

[0025] According to various embodiments of the present disclosure, a method for forming a gate structure is provided, the method comprising: providing a substrate including a surface in a reaction chamber; and performing at least one lanthanum oxide deposition cycle to form a lanthanum oxide film, wherein the lanthanum oxide deposition cycle comprises: pulsed lanthanum precursor, wherein the lanthanum precursor comprises tris(N,N'-diisopropylformamidinyl)lanthanum(III), and pulsed reactants into the reaction chamber, wherein the reactants comprise H2O, and wherein the reactants do not comprise O2 or O3.

[0026] According to various embodiments of the present disclosure, a system for depositing rare earth metal oxide films is provided, the system comprising: a reaction chamber; a pedestal in the reaction chamber configured to hold a substrate; a rare earth metal precursor source configured to provide a rare earth metal precursor into the reaction chamber, wherein the rare earth metal precursor comprises a rare earth metal, and wherein the rare earth metal precursor comprises a metal-organic precursor; a reactant source configured to provide a reactant into the reaction chamber, wherein the reactant comprises at least one of H2O, hydrogen peroxide, or N2O; and a controller including an addressable storage medium, wherein the controller is configured to control the gas flow rate into the reaction chamber, the temperature of the reaction chamber, the pressure of the reaction chamber, and the movement of the substrate to: provide the substrate on the pedestal, and perform at least one rare earth metal oxide deposition cycle, wherein the rare earth metal oxide deposition cycle includes: pulsed rare earth metal precursor, and pulsed reactant into the reaction chamber.

[0027] According to one or more embodiments, a method for depositing a rare earth metal oxide film is provided. An exemplary method includes providing a substrate in a reaction chamber containing a reaction space. The exemplary method may further include performing at least one rare earth metal oxide deposition cycle. In some embodiments, the rare earth metal deposition cycle includes pulsed a rare earth metal precursor to the reaction space and pulsed a reactant to the reaction space. In some embodiments, the rare earth metal deposition cycle is a cyclic deposition process, such as atomic layer deposition (ALD).

[0028] The rare earth metal precursor comprises at least one rare earth metal. In some embodiments, the rare earth metal precursor comprises lanthanum. In some embodiments, the rare earth metal precursor comprises an organometallic precursor. In some embodiments, the rare earth metal precursor comprises an amidine group. In some embodiments, the rare earth metal precursor comprises formamidinium. In some embodiments, the rare earth metal precursor comprises tris(N,N'-diisopropylformamidinyl)lanthanum(III).

[0029] In some embodiments, the reactants comprise an oxidizing agent. In some embodiments, the oxidizing agent comprises one or more of any combination of H2O, hydrogen peroxide, N2O, O2, or O3. In some embodiments, the reactants do not comprise O2 or O3. In some embodiments, the reactants comprise H2O.

[0030] In an exemplary embodiment, the rare earth metal precursor comprises tris(N,N'-diisopropylmethylammonium)lanthanum(III), and the reactant comprises H2O.

[0031] In some embodiments, the rare earth metal oxide deposition cycle is repeated multiple times. In some embodiments, the rare earth metal oxide deposition cycle is repeated at least 10 times, or at least 20 times. In some embodiments of repeated rare earth metal oxide deposition cycles, a periodic alumina cycle is performed after between about 10 and about 20 rare earth metal deposition cycles.

[0032] In some embodiments, the periodic alumina cycle includes removing the substrate from the reaction space or reaction chamber. The periodic alumina cycle continues after the substrate is removed from the reaction space by pulsed aluminum precursor onto the surface of the reaction space. In some embodiments, the periodic alumina cycle further includes pulsed oxygen reactant onto the surface of the reaction space to form alumina on the surface of the reaction space. In some embodiments, the periodic alumina cycle continues after the pulsed oxygen reactant, wherein the substrate is reintroduced into the reaction space or reaction chamber. In some embodiments, at least one rare earth metal oxide deposition cycle is performed after the periodic alumina cycle.

[0033] In some embodiments, the rare earth metal deposition cycle is a thermal process. In some embodiments, the substrate is not exposed to plasma during the rare earth metal deposition cycle. In some embodiments, the substrate processing method is a thermal process.

[0034] According to further examples of this disclosure, devices and / or devices comprising the structures described herein are formed using the methods described herein.

[0035] According to other exemplary embodiments of this disclosure, systems are provided for performing the methods described herein and / or for forming structures as described herein.

[0036] These and other embodiments will become apparent to those skilled in the art from the following detailed description of certain embodiments with reference to the accompanying drawings; the invention is not limited to any particular embodiment disclosed. Attached Figure Description

[0037] Figure 1 Methods according to one or more embodiments of this disclosure are illustrated;

[0038] Figure 2 A rare earth metal oxide deposition cycle according to one or more embodiments of the present disclosure is illustrated;

[0039] Figure 3 A periodic alumina cycle according to one or more embodiments of the present disclosure is illustrated;

[0040] Figure 4 An example of a substrate processing apparatus according to one or more examples of this disclosure is shown;

[0041] Figure 5 Examples of structures forming part of a device according to one or more examples of this disclosure are shown;

[0042] Figure 6 Another example of a structure forming part of a device according to one or more examples of this disclosure is shown.

[0043] It should be understood that the elements in the accompanying drawings are shown for simplicity and clarity and are not necessarily drawn to scale. For example, the dimensions of some elements in the drawings may be exaggerated relative to other elements to aid in understanding the embodiments shown in this disclosure. Detailed Implementation

[0044] The following description of exemplary embodiments of methods, structures, devices, and systems is merely exemplary and for illustrative purposes only; the following description is not intended to limit the scope of this disclosure or the claims. Furthermore, the description of multiple embodiments having the described features is not intended to exclude other embodiments having additional features or other embodiments including different combinations of the described features. For example, various embodiments are set forth as exemplary embodiments and may be recited in the dependent claims. Unless otherwise stated, exemplary embodiments or components thereof may be combined or may be applied separately from each other.

[0045] As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items. Unless otherwise stated, expressions such as “at least one of…” modify the entire column of elements when following an element in the column, and not necessarily any individual element in that column.

[0046] As used in this article, the singular forms “a,” “one,” and “the” are intended to include the plural forms as well, unless the context otherwise indicates.

[0047] As used herein, the term "substrate" can refer to any one or more underlying materials that can be used to form or on which devices, circuits, or films can be formed. A substrate may comprise a bulk material, such as silicon (e.g., single-crystal silicon), other group IV materials (e.g., germanium), or compound semiconductor materials (e.g., group III-V or group II-VI semiconductors), and may comprise one or more layers overlaid or underlaid on the bulk material.

[0048] In some embodiments, "film" refers to a layer extending in a direction perpendicular to the thickness direction. In some embodiments, "layer" refers to a material of a certain thickness formed on a surface, and can be synonymous with a film or non-film structure. A film or layer may consist of discrete single films or layers or multiple films or layers having certain properties, and the boundaries between adjacent films or layers may or may not be clear, and may or may not be based on the physical, chemical and / or any other properties, formation process or sequence and / or function or purpose of adjacent films or layers. A layer or film may be continuous or discontinuous. Furthermore, a single film or layer may be formed using one or more deposition cycles and / or one or more deposition and processing cycles.

[0049] As used herein, the term "structure" can refer to a device structure that is partially or fully fabricated. For example, a structure can be a substrate or a substrate having one or more layers and / or features formed thereon.

[0050] As used in this article, the term "coverage" can refer to two membranes that are in direct contact with each other.

[0051] As used herein, the term "cyclic deposition process" or "cyclic deposition process" can refer to a vapor phase deposition process in which deposition cycles (typically multiple consecutive deposition cycles) are performed in a processing chamber. Cyclic deposition processes can include, for example, cyclic chemical vapor deposition (CCVD) and / or atomic layer deposition (ALD) processes.

[0052] As used in this article, “rare earth metals” include scandium, yttrium, the lanthanides (lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium) and the actinides (actinium, thorium, protactinium, uranium, neptunium, plutonium, americium, curium, beryllium, californium, neptunium, francium, noreium, and ruthenium).

[0053] In this disclosure, any two numbers of a variable may constitute a feasible range of the variable, and any indicated range may include or exclude endpoints. Furthermore, any value of the indicated variable (whether or not it is indicated by “about”) may refer to an exact value or an approximate value and includes equivalents, and in some embodiments may refer to an average, median, representative value, or multi-value. Additionally, in this disclosure, the terms “comprising,” “including,” “consisting of,” and “having,” etc., may independently mean “generally or broadly comprising,” “including,” “substantially consisting of,” or “consisting of” in some embodiments. The meaning of any definition in this disclosure does not necessarily exclude the common and customary meanings in some embodiments.

[0054] Figure 1 A method 100 for depositing a rare-earth metal oxide film on a substrate according to exemplary embodiments of the present disclosure is illustrated. In some embodiments, method 100 can be used to form a dipole layer. In some embodiments, the dipole layer is formed using a "dipole-first" method. In some embodiments, the dipole layer is formed using a "dipole-last" method. In some embodiments, the dipole layer is formed using a "dipole-intermediate" method.

[0055] Method 100 includes the following steps: providing a substrate within the reaction space of a reaction chamber (step 110), optionally depositing a first transition metal oxide film (step 120), performing a rare earth deposition cycle to deposit a rare earth metal oxide film (step 130), optionally repeating the rare earth metal oxide deposition cycle step (loop 140), optionally performing a periodic alumina cycle (step 150), optionally annealing the rare earth metal oxide film (step 160), and optionally depositing a second transition metal oxide film (step 170).

[0056] During step 110, a substrate is provided into the reaction space within the reaction chamber. According to examples of this disclosure, the reaction chamber may form part of a chemical vapor deposition reactor, such as a chemical vapor deposition (CVD) reactor, an atomic layer deposition (ALD) reactor, etc. Various steps of the methods described herein may be performed in a single reaction chamber or in multiple reaction chambers (e.g., reaction chambers of clustered tools).

[0057] In some embodiments, the substrate includes a surface comprising one or more of silicon oxide, silicon nitride, or silicon oxynitride. In other embodiments, the surface comprises a transition metal oxide, such as hafnium oxide. In other embodiments, the surface comprises a transition metal oxide, such as hafnium oxide, covering one or more of silicon oxide, silicon nitride, or silicon oxynitride.

[0058] During step 110, the substrate may be brought to a desired temperature and / or the reaction space may be brought to a desired pressure, such as a temperature and / or pressure suitable for subsequent steps. For example, the temperature within the reaction space (e.g., the temperature of the substrate or substrate support) may be between about 150°C and about 350°C, or between about 200°C and about 300°C, or between about 230°C and about 270°C. For example, the pressure within the reaction space may be less than or equal to 10 Torr, or between about 0.5 Torr and 10 Torr, or between about 2 Torr and about 6 Torr.

[0059] Method 100 may optionally continue by depositing a first transition metal oxide film on the substrate. In some embodiments, the first transition metal oxide film is deposited on one or more of silicon oxide, silicon nitride, or silicon oxynitride on the surface of the substrate. The transition metal oxide can be deposited by any suitable method, including a cyclic deposition process. In some embodiments, the first transition metal oxide film comprises one or more of hafnium, zirconium, niobium, titanium, vanadium, tungsten, molybdenum, or tantalum. In some embodiments, the first transition metal oxide film has a thickness between about 5 angstroms and about 30 angstroms, or between about 13 angstroms and about 20 angstroms.

[0060] Method 100 continues to perform a rare earth metal oxide deposition cycle to deposit a rare earth metal oxide film. In some embodiments, the rare earth metal oxide is a cyclic deposition process, such as cyclic chemical vapor deposition (CCVD) or atomic layer deposition (ALD). In some embodiments, the rare earth metal oxide film is deposited directly on a transition metal oxide film. In some embodiments of depositing a first transition metal oxide film, the rare earth metal oxide film may be deposited directly on the first transition metal oxide film. In some embodiments, during the rare earth metal oxide deposition cycle, the temperature within the reaction space (e.g., the temperature of the substrate or substrate support) may be between about 150°C and about 350°C, or between about 200°C and about 300°C, or between about 230°C and about 270°C. In some embodiments, the pressure within the reaction space during the rare earth metal oxide deposition cycle may be less than or equal to 10 Torr, or between about 0.5 Torr and 10 Torr, or between about 2 Torr and about 6 Torr.

[0061] Figure 2 It shows the applicable Figure 1 Method 200 of step 130 in the figure. Method 200 includes a step 210 of pulsed rare earth metal precursor to the reaction space and a step 220 of pulsed reactant to the reaction space. Method 200 may also include an optional purge step 215 after the pulsed rare earth metal precursor step 210 and / or an optional purge step 225 after the pulsed reactant step 220. Optional purge steps 215 and 225 may remove gases, precursors, reactants and / or byproducts from the reaction space. As shown, method 200 may include repeating a rare earth metal oxide cycle (loop 230) a desired number of times. In some embodiments, the rare earth metal oxide cycle may include a pulsed reactant 220 performed prior to the pulsed rare earth metal precursor 210. In some embodiments, the rare earth metal oxide cycle may include any sub-steps 210, 215, 220 or 225 repeated multiple times. In some embodiments, the steps of pulsed rare earth metal precursor 210 and pulsed reactant 220 may at least partially overlap in time.

[0062] The rare earth metal precursor comprises a rare earth metal. In some embodiments, the rare earth metal comprises lanthanum. In some embodiments, the rare earth metal precursor comprises an organometallic precursor. In some embodiments, the rare earth metal precursor comprises an amidine group. In some embodiments, the rare earth metal precursor comprises formamidinium. In some embodiments, the rare earth metal precursor comprises tris(N,N'-diisopropylformamidinyl)lanthanum(III).

[0063] In some embodiments, the reactants comprise an oxidizing agent. In some embodiments, the oxidizing agent comprises one or more of any combination of H2O, hydrogen peroxide, N2O, O2, or O3. In some embodiments, the reactants do not comprise O2 or O3. In some embodiments, the reactants comprise H2O.

[0064] In an exemplary embodiment, the rare earth metal precursor comprises tris(N,N'-diisopropylmethylammonium)lanthanum(III), and the reactant comprises H₂O. The rare earth metal oxide film deposited using tris(N,N'-diisopropylmethylammonium)lanthanum(III) and H₂O may have a small amount of carbon impurities. In some embodiments, the rare earth metal oxide film deposited using tris(N,N'-diisopropylmethylammonium)lanthanum(III) and H₂O may have a carbon atom percentage of less than about 10 atomic%, or less than 5 atomic%, or less than 1 atomic%.

[0065] return Figure 1 Method 100 may optionally continue to repeat the steps of the rare earth metal oxide deposition cycle (loop 140). In some embodiments, the rare earth metal oxide deposition cycle is repeated multiple times. In some embodiments, the rare earth metal oxide deposition cycle is repeated multiple times until the rare earth metal oxide film reaches between about 2 angstroms and about 15 angstroms, or between 3 angstroms and 10 angstroms, or between about 3 angstroms and about 5 angstroms.

[0066] In some embodiments, method 100 includes the optional step of performing a periodic alumina cycle between rare earth metal deposition cycles. In some embodiments of repeated rare earth metal oxide deposition cycles, a periodic alumina cycle is performed after multiple rare earth metal deposition cycles. In some embodiments of repeated rare earth metal oxide deposition cycles, a periodic alumina cycle is performed after between about 10 and 20 rare earth metal deposition cycles.

[0067] Figure 3 It shows the applicable Figure 1 The method 300 of step 150 in the process. In some embodiments, the periodic alumina cycle includes removing the substrate from the reaction space and / or reaction chamber. The periodic alumina cycle continues by pulsed aluminum precursor onto the surface of the reaction space. In some embodiments, the periodic alumina cycle further includes pulsed oxygen reactant onto the surface of the reaction space to deposit alumina on the surface of the reaction space. In some embodiments where the periodic alumina cycle includes removing the substrate from the reaction space and / or reaction chamber, the periodic alumina cycle continues after pulsed oxygen reactant and reintroducing the substrate into the reaction space and / or reaction chamber. In some embodiments, one or more rare earth metal oxide deposition cycles are performed after the periodic alumina cycle.

[0068] Back Figure 1Method 100 may optionally continue to anneal the rare earth metal oxide film (step 160). In some embodiments, the rare earth metal oxide film is annealed at a temperature between about 550°C and about 950°C or between about 600°C and 750°C.

[0069] Method 100 may continue to deposit a second transition metal oxide film on the substrate (step 170). The second transition metal oxide film may be deposited by any suitable method, including a cyclic deposition process. In some embodiments, the second transition metal oxide film comprises one or more of hafnium, zirconium, niobium, titanium, vanadium, tungsten, molybdenum, or tantalum. In some embodiments, the thickness of the second transition metal oxide film is between about 5 angstroms and about 30 angstroms, or between about 13 angstroms and about 20 angstroms. In some embodiments, the second transition metal oxide film is deposited directly on a rare earth metal oxide film. In some embodiments, the temperature within the reaction space (e.g., the temperature of the substrate or substrate support) during the deposition of the second transition metal oxide film may be between about 150°C and about 350°C, or between about 200°C and about 300°C, or between about 230°C and about 270°C. In some embodiments, the pressure within the reaction space during the deposition of the second transition metal oxide film may be less than or equal to 10 Torr, or between about 0.5 Torr and 10 Torr, or between about 2 Torr and about 6 Torr.

[0070] In some embodiments, the annealing step 160 may be performed after the deposition of the second transition metal oxide 170. In some embodiments, the annealing step 160 may be performed before the deposition of the second transition metal oxide 170.

[0071] Additionally, the carrier gas and / or inert gas may flow together throughout method 100 or during any sub-step of method 100. For example, the carrier gas and / or inert gas may be one or more of helium, argon, or nitrogen.

[0072] Some embodiments of method 100 can produce a dipole layer comprising a rare-earth metal oxide. In some embodiments, the dipole layer has a thickness of about 8 angstroms to about 30 angstroms. In embodiments where a first transition metal oxide film is not formed or where the rare-earth metal oxide is formed on silicon oxide, silicon nitride, or silicon oxynitride (below the rare-earth metal oxide film), the method can be used as a dipole-first method to form the dipole layer. In embodiments where the rare-earth metal oxide is formed on the transition metal oxide and no second transition metal oxide film is formed, the method can be used as a dipole-last method to form the dipole layer. In embodiments where the rare-earth metal oxide is formed on and / or covers the transition metal oxide and a second transition metal oxide film is formed on and / or covers the rare-earth metal oxide, the method can be used as a dipole-intermediate method to form the dipole layer.

[0073] Figure 4 An example of a substrate processing apparatus 400 according to one or more examples of this disclosure is shown. Apparatus 400 can be used to perform the methods described herein and / or form structural or device portions as described herein.

[0074] In the example shown, device 400 includes one or more reaction chambers 402, reaction space 403, rare earth metal precursor gas source 404, aluminum precursor gas source 406, first reactant gas source 408, second oxygen reactant gas source 410, exhaust source 422, and controller 412.

[0075] Reaction chamber 402 may include any suitable reaction chamber, such as an atomic layer deposition (ALD) or chemical vapor deposition (CVD) reaction chamber.

[0076] Rare earth metal precursor gas source 404 may include a container and one or more rare earth metal precursors as described herein—either alone or mixed with one or more carrier gases (e.g., inert gases). Aluminum precursor gas source 406 may include a container and one or more metal precursors as described herein—either alone or mixed with one or more carrier gases (e.g., inert gases). Reactant gas source 408 may include a container and one or more reactants as described herein—either alone or mixed with one or more carrier gases. Second oxygen reactant gas source 410 may include one or more oxygen reactant gases as described herein. Although four gas sources 404-410 are shown, apparatus 400 may include any suitable number of gas sources. Gas sources 404-410 may be connected to reaction chamber 402 via lines 414-420, each of which may include a flow controller, valve, heater, etc.

[0077] The exhaust source 422 may include one or more vacuum pumps.

[0078] Controller 412 includes electronic circuitry and software to selectively operate valves, manifolds, heaters, pumps, and other components included in apparatus 400. Such circuitry and components operate to introduce precursors, reactants, and gases from respective sources 404-410. Controller 412 can control the timing of gas pulse sequences, the temperature of the substrate and / or reaction chamber, the pressure within the reaction chamber, and various other operations to provide appropriate operation of apparatus 400. Controller 412 may include control software to electrically or pneumatically control valves to control the inflow and outflow of precursors, reactants, and purge gases from reaction chamber 402. Controller 412 may include modules, such as software or hardware components like FPGAs or ASICs, to perform certain tasks. Modules may advantageously be configured to reside on addressable storage media of the control system and configured to perform one or more processes or methods as described herein.

[0079] Other configurations of the apparatus 400 are possible, including different numbers and types of precursor and reactant sources, as well as purge gas sources. Furthermore, it should be understood that numerous arrangements of valves, conduits, precursor sources, and purge gas sources exist to achieve the objective of selectively supplying gases to the reaction chamber 402. Additionally, for the sake of illustrative purposes and for simplicity, many components have been omitted, and these components may include, for example, various valves, manifolds, purifiers, heaters, containers, vents, and / or bypasses.

[0080] During operation of the apparatus 400, a substrate, such as a semiconductor wafer (not shown), is transferred from, for example, a substrate transport system to a reaction chamber 402. Once the substrate is transferred to the reaction chamber 402, one or more gases (e.g., precursors, reactants, carrier gases, and / or purge gases) from gas sources 404-410 are introduced into the reaction chamber 402.

[0081] Figure 5 The structure / part of a device 500 according to an additional example of the present disclosure is shown. The device or structure 500 includes a substrate 510, a film 520 comprising a rare earth metal oxide, and a film 530 comprising a transition metal oxide. In some embodiments, the device or structure 500 is at least a portion of a gate structure. The rare earth metal oxide film 520 can be formed by the methods described in the present disclosure. In some embodiments, the rare earth metal oxide film 520 is lanthanum oxide. The rare earth metal oxide film 520 may have a thickness of less than 15 angstroms, less than 10 angstroms, or between about 3 angstroms and about 5 angstroms. The transition metal oxide film 530 can be formed by the methods described in the present disclosure. In some embodiments, the transition metal oxide film 530 is hafnium oxide. The transition metal oxide film 530 may have a thickness between about 5 angstroms and about 30 angstroms, or between about 13 angstroms and 20 angstroms. In some embodiments, a film comprising the transition metal oxide 530 covers a film comprising the rare earth metal oxide 520.

[0082] Figure 6The structure / part of a device 600 according to an additional example of the present disclosure is shown. The device or structure 600 includes a substrate 610, a film 640 comprising a first transition metal oxide, a film 630 comprising a rare earth metal oxide, and a film 640 comprising a second transition metal oxide. In some embodiments, the device or structure 600 is at least a portion of a gate structure. The first transition metal oxide film 610 can be formed by the methods described in the present disclosure. In some embodiments, the first transition metal oxide film 610 is hafnium oxide. The first transition metal oxide film 610 may have a thickness between about 5 angstroms and about 30 angstroms, or between about 13 angstroms and 20 angstroms. The rare earth metal oxide film 630 can be formed by the methods described in the present disclosure. In some embodiments, the rare earth metal oxide film 630 is lanthanum oxide. The rare earth metal oxide film 630 may have a thickness of less than 15 angstroms, less than 10 angstroms, or between about 3 angstroms and about 5 angstroms. The second transition metal oxide film 640 can be formed by the methods described in the present disclosure. In some embodiments, the second transition metal oxide film 640 is hafnium oxide. The second transition metal oxide film 640 may have a thickness between about 5 angstroms and about 30 angstroms or between about 13 angstroms and 20 angstroms. In some embodiments, the film 640 comprising the second transition metal oxide covers the film 630 comprising the rare earth metal oxide, and the film 630 comprising the rare earth metal oxide covers the film 620 comprising the transition metal oxide.

[0083] The exemplary embodiments described above do not limit the scope of the invention, as these embodiments are merely examples of embodiments of the invention, the scope of which is defined by the appended claims and their legal equivalents. Any equivalent embodiments are intended to fall within the scope of the invention. In fact, various modifications to this disclosure, such as alternative useful combinations of the described elements, in addition to those shown and described herein, will become apparent to those skilled in the art from the description. These modifications and embodiments are also intended to fall within the scope of the appended claims.

Claims

1. A method for depositing rare earth metal oxide films, the method comprising: A substrate including a surface is provided in a reaction chamber including a reaction space; and Perform at least one rare earth metal oxide deposition cycle to deposit a rare earth metal oxide film, wherein the rare earth metal oxide deposition cycle includes: A rare earth metal precursor is pulsed into the reaction space, wherein the rare earth metal precursor comprises a rare earth metal, and wherein the rare earth metal precursor includes a metal-organic precursor, and The reactants are pulsed into the reaction space, wherein the reactants include an oxidant, which includes one or more of H2O, hydrogen peroxide or N2O.

2. The method according to claim 1, wherein, The rare earth metal precursor includes formamidinium.

3. The method according to claim 2, wherein, The rare earth metal precursor comprises tris(N,N'-diisopropylformamidinyl)lanthanum(III).

4. The method according to claim 1, wherein, The reactants include H2O.

5. The method according to claim 4, wherein, The reactants consist of H2O and an optional inert gas / carrier gas.

6. The method according to claim 1, wherein, The surface comprises one or more of silicon oxide, silicon nitride, or silicon oxynitride, and wherein the rare earth metal oxide film is deposited on one or more of silicon oxide, silicon nitride, or silicon oxynitride.

7. The method according to claim 1 further comprises depositing a transition metal oxide on the rare earth metal oxide film.

8. The method according to claim 7, wherein, The transition metal oxide includes hafnium oxide.

9. The method according to claim 7, wherein, The rare earth metal oxide film has a thickness of less than 15 angstroms.

10. The method according to claim 1, wherein, The surface includes one or more of silicon oxide, silicon nitride, or silicon oxynitride, wherein a first hafnium oxide film is deposited on one or more of silicon oxide, silicon nitride, and silicon oxynitride, and wherein the rare earth metal oxide film is deposited on the first hafnium oxide film.

11. The method according to claim 10, wherein, A second hafnium oxide film is deposited on the rare earth metal oxide film.

12. The method according to claim 3, wherein, The reactants include H2O.

13. The method according to claim 1, further comprising repeating the rare earth metal oxide deposition cycle at least 20 times, wherein, A periodic alumina cycle is performed after approximately 10 to 20 rare earth metal deposition cycles, wherein the periodic alumina cycle includes: Remove the substrate from the reaction chamber. After the substrate is removed from the reaction chamber, the aluminum precursor is pulsed onto the surface of the reaction space. The oxygen reactants are pulsed onto the surface of the reaction space to form aluminum oxide on the surface of the reaction space, and After the pulsed oxygen reactants, the substrate is reintroduced into the reaction chamber.

14. The method according to claim 1, wherein, The method described is a thermal process.

15. The method according to claim 1, wherein, The reactants do not contain O2 or O3.

16. The method according to claim 1, further comprising annealing the rare earth metal oxide film, wherein, The temperature during annealing is below approximately 600°C.

17. The method according to claim 12, wherein, The rare earth metal oxide film has less than 10 atomic percent carbon atoms.

18. The method according to claim 1, wherein, The temperature during the step of performing at least one rare earth metal oxide deposition cycle is between about 150°C and about 350°C, and the pressure during the step of performing at least one rare earth metal oxide deposition cycle is between about 0.5 Torr and about 10 Torr.

19. A method for forming a gate structure, the method comprising: A substrate containing the surface is provided in the reaction chamber; and Perform at least one lanthanum oxide deposition cycle to form a lanthanum oxide film, wherein the lanthanum oxide deposition cycle includes: Pulsed lanthanum precursor, wherein the lanthanum precursor comprises tris(N,N'-diisopropylmethylamidinyl)lanthanum(III), and The reactants are pulsed into the reaction chamber, wherein the reactants contain H2O and wherein the reactants do not contain O2 or O3.

20. A system for depositing rare earth metal oxide films, the system comprising: Reaction chamber; A base in the reaction chamber, configured to hold the substrate; A rare earth metal precursor source configured to provide a rare earth metal precursor to a reaction chamber, wherein the rare earth metal precursor comprises a rare earth metal, and wherein the rare earth metal precursor comprises a metal-organic precursor. A reactant source configured to supply reactants to a reaction chamber, wherein the reactants include at least one selected from H₂O, hydrogen peroxide, or N₂O; and A controller, including an addressable storage medium, wherein the controller is configured to control the gas flow rate into the reaction chamber, the temperature of the reaction chamber, the pressure of the reaction chamber, and the movement of the substrate to: A substrate is provided on the base, and Perform at least one rare earth metal oxide deposition cycle, wherein the rare earth metal oxide deposition cycle includes: Pulsed rare earth metal precursors, and The reactants are pulsed into the reaction chamber.

Images