Method of forming doped hafnium zirconium oxide layer on substrate

Abstract

The techniques of the present disclosure generally relate to the field of capacitor devices. More specifically, the present invention relates to a metal-insulator-metal capacitor (MIM CAPS) including a hafnium zirconium oxide (HZO) layer and a method of manufacturing the same. Related methods, deposition systems, and apparatuses are also described. A method of forming a doped HZO layer on a substrate includes the steps of: providing a substrate in a reaction chamber; performing one or more cycles, whereby each cycle comprises contacting a hafnium precursor, a zirconium precursor, an oxygen reactant, a dopant precursor, and a reactant on at least a portion of the substrate by introducing the precursors into the reaction chamber; the dopant precursor includes a dopant element having three or four valence electrons having an atomic radius less than the atomic radius of the Hf or Zr element of the HZO layer.

Description

Technical Field

[0001] The present disclosure relates generally to the field of capacitor devices and more particularly to metal-insulator-metal capacitors (MIM CAPS) including hafnium zirconium oxide (HZO) layers and methods for making the same. Background Art

[0002] A capacitor is an electronic component used to store and regulate electrical energy in an electric field by accumulating charge on two closely spaced surfaces that are insulated from each other. In general, capacitors are components that are widely used as circuit parts in many common electrical devices and are designed to have specific capacitance values ​​and voltage ratings to suit the requirements of various applications. Most capacitors contain at least two electrical conductors that serve as electrodes of the capacitor and are separated by an insulating layer. These structures are also known as metal-insulator-metal capacitors (MIM CAPS). The non-conductive insulator or dielectric acts to increase the charge capacity of the capacitor. An ideal capacitor is characterized by a constant capacitance C. The capacitance between two conductors is a function of the geometry or surface area of ​​the conductors, the distance between the two conductors, and the dielectric constant of the isolating material between them. In a capacitor, the highest capacitance is achieved with dielectric materials of high dielectric constants, large plate areas, and small spacing between the plates. The relative dielectric constant is an important parameter when designing a capacitor. If a material with a high relative dielectric constant is placed in an electric field, the magnitude of the electric field will be significantly reduced within the volume of the dielectric. This fact is often used to increase the capacitance of a particular capacitor design.

[0003] Next generation MIM CAPS for logic and memory applications desire very high dielectric constant values ​​κ while having linear capacitance-voltage (CV) characteristics. High dielectric constant values ​​and high capacitance density can be achieved by using ferroelectric / antiferroelectric zirconium hafnium oxide (HZO) layers, resulting in dielectric constant values ​​κ greater than 40 and experiencing low leakage. However, the problem with such capacitors is that the CV characteristics are nonlinear and result in a peak dielectric constant value κ near 0V, while the dielectric constant value κ at other desired fields may be significantly lower. In addition, it has proven difficult to integrate such materials with nonlinear CV characteristics into devices or circuits. Therefore, there is a need to develop alternative materials with linear CV characteristics and dielectric constant value κ peaks. Summary of the invention

[0004] 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 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.

[0005] One aspect of the present disclosure relates to a method of forming a doped hafnium zirconium oxide (HZO) layer on a substrate, the method comprising the following steps:

[0006] a) providing the substrate in a reaction chamber;

[0007] b) executing one or more loops, the loops comprising:

[0008] i. a hafnium precursor pulse, wherein at least a portion of the substrate is contacted with one or more hafnium precursors by introducing the one or more hafnium precursors into the reaction chamber;

[0009] ii. a zirconium precursor pulse, wherein at least a portion of the substrate is contacted with one or more zirconium precursors by introducing the one or more zirconium precursors into the reaction chamber;

[0010] iii. an oxygen reactant pulse, wherein at least a portion of the substrate is contacted with one or more oxygen reactants by introducing the one or more oxygen reactants into the reaction chamber; and

[0011] iv. a dopant precursor pulse, wherein at least a portion of the substrate is contacted with one or more dopant precursors by introducing the one or more dopant precursors into the reaction chamber,

[0012] Thereby forming a doped HZO layer;

[0013] The dopant precursor includes a dopant element characterized by having three or four valence electrons and an atomic radius smaller than the atomic radius of the Hf or Zr element of the HZO layer.

[0014] In certain embodiments, the methods disclosed herein provide for performing an oxygen reactant pulse after each hafnium precursor pulse and / or after each zirconium precursor pulse.

[0015] In certain embodiments, the methods disclosed herein provide that the hafnium precursor pulse is followed by a dopant precursor pulse without any intermediate oxygen reactant pulse.

[0016] In certain embodiments, the methods disclosed herein provide that the dopant precursor pulse is performed after the zirconium precursor pulse without any intermediate oxygen reactant pulse.

[0017] In certain embodiments, the methods disclosed herein provide that each pulse is followed by a purge with an inert gas selected from at least one of N 2 and a noble gas.

[0018] In certain embodiments, the methods disclosed herein provide that the hafnium precursor pulse, the zirconium precursor pulse, the oxygen reactant pulse, and / or the dopant precursor pulse include a plurality of micropulses.

[0019] In certain embodiments, the methods disclosed herein provide that the dopant element is selected from the group consisting of aluminum (Al), silicon (Si), nickel (Ni), germanium (Ge), gallium (Ga), and carbon (C).

[0020] In a specific embodiment, the method disclosed herein provides that the concentration range of the dopant element in the HZO layer is between 0.50% and 8.0% relative to the dopant element concentration, more particularly between 1.0% and 5.0% relative to the dopant element concentration, and even more particularly between 2.0% and 4.50% relative to the dopant element concentration.

[0021] In a specific embodiment, the dopant element used in the method is Al. In particular, the dopant precursor is a low-reactivity precursor, which is preferably composed of the general formula Al(R 1 )3 represents a low-reactivity aluminum precursor, wherein each R 1 are independently selected from hydrogen, halogen, alkyl, alkenyl, N(R 2 )2, cycloalkyl and alkoxy, and each R 2 is selected from hydrogen, alkyl or alkenyl. In particular, each R 1 are independently selected from hydrogen, halogen, C 1-8 Alkyl, C 2-8 Alkenyl, C 3-8 Cycloalkyl and C 1-8 alkoxy, and wherein each R 2 Selected from hydrogen, C 1-8 Alkyl or C 2-8 In particular, the aluminum precursor is selected from aluminum hydride (AlH3), aluminum trifluoride (AlF3), aluminum trichloride (AlCl3), aluminum tribromide (AlBr3), aluminum triiodide (AlI3), trimethylaluminum (Al(CH3)3), triethylaluminum Al(C2H5)3), triisopropylaluminum (Al( i Pr)3), tetra-n-butylaluminum (Al(C4H9)3), tetra-tert-butylaluminum (Al(O t Bu)3), aluminum methoxide (Al(OCH3)3), aluminum ethoxide (Al(OC2H5)3), aluminum isopropoxide (Al(O i Pr)3), aluminum n-butoxide (Al(OC4H9)3) and aluminum tert-butoxide (Al(O t Bu)3).

[0022] In a particular embodiment, the dopant element used in the method is Si. In particular, the dopant precursor is a low-reactivity precursor, which is preferably selected from tetraacetic acid silicon (Si(OOCCH3)4) and Si(R 3 )4, wherein each R 3are independently selected from hydrogen, halogen, alkyl, alkenyl, N(R 4 )2, cycloalkyl and alkoxy, and each R 4 is selected from hydrogen, alkyl or alkenyl. In particular, each R 3 are independently selected from hydrogen, halogen, C 1-8 Alkyl, C 2-8 Alkenyl, C 3-8 Cycloalkyl and C 1-8 alkoxy, and wherein each R 4 Selected from hydrogen, C 1-8 Alkyl or C 2-8 In particular, the silicon precursor is selected from silane (SiH4), silicon tetrafluoride (SiF4), silicon tetrachloride (SiCl4), silicon tetrabromide (SiBr4), silicon tetraiodide (SiI4), tetramethylsilane (Si(CH3)4), tetraethylsilane (Si(C2H5)4), tetra(isopropyl)silane (Si( i Pr)4), tetra-n-butylsilane (Si(C4H9)4), tetra-tert-butylsilane (Si(O t Bu)4), tetramethoxysilane (Si(OCH3)44), tetraethoxysilane (Si(OC2H5)4), tetra(isopropoxy)silane (Si(O i Pr)4), tetra-n-butoxysilane (Si(OC4H9)4), tetra-tert-butoxysilane (Si(O t Bu)4) and tris(dimethylamino)silane (Si(N[CH3]2)3).

[0023] In a specific embodiment, the dopant element used in the method is Ge. In particular, the dopant precursor is a low-reactivity precursor, which is preferably composed of the general formula Ge(R 5 )4 represented by a low-reactivity germanium precursor, wherein each R 5 are independently selected from hydrogen, halogen, alkyl, alkenyl, N(R 6 )2, cycloalkyl and alkoxy, and each R 6 is selected from hydrogen, alkyl or alkenyl. In particular, each R 5 are independently selected from hydrogen, halogen, C 1-8 Alkyl, C 2-8 Alkenyl, C 3-8 Cycloalkyl and C 1-8 alkoxy, and wherein each R 6 Selected from hydrogen, C 1-8 Alkyl or C 2-8In particular, the germanium precursor is selected from germanium (GeH4), germanium tetrafluoride (GeF4), germanium tetrachloride (GeCl4), germanium tetrabromide (GeBr4), germanium tetraiodide (GeI4), tetramethylgermanium (Ge(CH3)4), tetraethylgermanium (Ge(C2H5)4), tetra(isopropyl)germanium (Ge( i Pr)4), tetra-n-butylgermanium (Ge(C4H9)4), tetra-tert-butylgermanium (Ge(O t Bu)4), tetramethoxygermanium (Ge(OCH3)4), tetraethoxygermanium (Ge(OC2H5)4), tetra(isopropoxy)germanium (Ge(OC3H7)4), tetra-n-butoxygermanium (Ge(OC4H9)4), tetra-tert-butoxygermanium (Ge(O t Bu)4), tetrakis(dimethylamino)germanium (Ge(N[CH3]2)4).

[0024] In a particular embodiment, the methods disclosed herein provide that the hafnium precursor is selected from the group consisting of HfCl4, HfBr4, HfI4, tetrakis(dimethylamino)hafnium (Hf(N(CH3)2)4), tetrakis(ethylmethylamino)hafnium (Hf(N(C2H5)(CH3))4), tetrakis(diethylamino)hafnium (Hf(N(C2H5)2)4), Hf(OR)4, tris(dimethylamino)cyclopentadienylhafnium (HfCp(NMe2)3), Hf(CpMe)2[OMe]Me, Hf(CpMe)2Me2 and tetrakis(1-methoxy-2-methyl-2-propoxy)hafnium (Hf(mmp)4).

[0025] In certain embodiments, the methods disclosed herein provide that the zirconium precursor is selected from tetrakis(dimethylamino)zirconium, tetrakis(diethylamino)zirconium, tetrakis(ethylmethylamino)zirconium, and tris(dimethylamino)cyclopentadienylzirconium.

[0026] In some embodiments, the methods disclosed herein provide for a decomposition temperature of the dopant precursor to be higher than the operating temperature for forming the doped hafnium zirconium oxide (HZO) layer.

[0027] In some embodiments, the methods disclosed herein provide that the operating temperature for forming the doped HZO layer is between 150°C and 450°C, preferably between 250°C and 350°C, and more preferably at about 300°C.

[0028] In some embodiments, the method disclosed herein is an atomic layer deposition (ALD) method.

[0029] In some embodiments, the method disclosed herein further comprises the step of providing a seed layer before forming the doped HZO layer, wherein the seed layer is a ZrO2 seed layer. Preferably, the substrate comprises a metal oxide (MO) surface layer, and / or wherein the method further comprises the step of forming a metal oxide (MO) top layer on the doped HZO layer, thereby forming a layered doped HZO structure. In addition, the MO surface layer and / or the MO top layer are in direct contact with the doped HZO layer. Preferably, the metal oxide is TiO2.

[0030] In some embodiments, the methods disclosed herein provide that the doped HZO layer stabilizes the tetragonal phase of the HZO layer such that a morphotropic phase boundary (MPB) is reached between the orthorhombic and tetragonal phases of the HZO layer to allow for changing the polarization switching voltage of the HZO layer.

[0031] In some embodiments, the methods disclosed herein provide that changing the polarization switching voltage of the HZO layer changes the capacitance-voltage (CV) linearity of the HZO layer.

[0032] In some embodiments, the methods disclosed herein provide that doping the HZO layer increases the dielectric constant value (κ) of the HZO layer.

[0033] In some embodiments, the methods disclosed herein provide that the dielectric constant value (κ) of the doped HZO layer is greater than 35, preferably greater than 45 at about -2 and -3 MV / cm.

[0034] In some embodiments, the methods disclosed herein provide that the doped HZO layer is formed without any intermediate vacuum interruption.

[0035] In certain embodiments, a doped hafnium zirconium oxide (HZO) layer is obtained by the methods disclosed herein.

[0036] In certain embodiments, a layered doped HZO structure is obtained by the methods disclosed herein.

[0037] In a specific embodiment, a doped hafnium zirconium oxide (HZO) layer is obtained by the method disclosed herein as an insulator in metal-insulator-metal capacitors (MIM CAPS).

[0038] 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 attached figures; the invention is not necessarily limited to any particular embodiment disclosed. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] A more complete understanding of exemplary embodiments of the present disclosure may be obtained by referring to the detailed description and claims when considered in conjunction with the following illustrative drawings.

[0040] Figure 1 Exemplary embodiments of a method for forming a doped hafnium zirconium oxide (HZO) layer on a substrate are described.

[0041] Figure 2a shows a first modification of the CV curve by doping the HZO layer according to the invention, Figure 2b shows a second modification of the CV curve by doping the HZO layer according to the present invention, Figure 2c A third modification of the CV curve by doping the HZO layer according to the present invention is shown.

[0042] Figure 3 An exemplary MIM capacitor 300 of the present disclosure is schematically illustrated.

[0043] Figure 4 Another exemplary MIM capacitor 400 of the present disclosure is schematically illustrated.

[0044] Figure 5 Another exemplary MIM capacitor 500 of the present disclosure is schematically illustrated.

[0045] Figure 6 A system 600 according to yet another exemplary embodiment of the present disclosure is schematically shown.

[0046] It should be understood that the elements in the drawings are shown for simplicity and clarity and are not necessarily drawn to scale. For example, the size of some elements in the drawings may be exaggerated relative to other elements to help improve the understanding of the illustrated embodiments of the present disclosure. DETAILED DESCRIPTION

[0047] Although certain embodiments and examples are disclosed below, those skilled in the art will appreciate that the disclosure extends beyond the specifically disclosed embodiments and / or uses of the disclosure and obvious modifications and equivalents thereof. Therefore, it is intended that the scope of the disclosure disclosed should not be limited by the specifically disclosed embodiments described below.

[0048] In the following detailed description, the underlying technology of the present disclosure will be described through different aspects of the present disclosure. It will be readily understood that the various aspects of the present disclosure, as generally described herein and shown in the accompanying drawings, may be arranged, replaced, combined and designed in a variety of different configurations, all of which are expressly intended and form part of the present disclosure. This description is intended to help the reader more easily understand the technical concepts, but is not meant to limit the scope of the present disclosure, which is limited only by the claims.

[0049] References throughout this specification to "one embodiment" or "an embodiment" mean that a particular feature, structure, or characteristic described in conjunction with the embodiment is included in at least one embodiment of the present disclosure. Therefore, the phrases "in one embodiment" or "in an embodiment" appearing in various places in this specification do not necessarily all refer to the same embodiment.

[0050] As used herein, the term "includes" and its variations are synonymous with "comprises" and its variations or "contains" and its variations, and are inclusive or open-ended and do not exclude additional, unlisted components, elements, or method steps. The term "includes" and its variations, when referring to the components, elements, or method steps, also include embodiments consisting of the components, elements, or method steps. The singular forms "a", "an", and "the" include singular and plural referents unless the context clearly dictates otherwise.

[0051] The objects described herein as "connected" or "coupled" reflect a functional relationship between the objects being described, that is, the term indicates that the objects being described must be connected in a manner to perform the specified function, which may be direct or indirect connection, in an electrical or non-electrical (i.e., physical) manner, as appropriate to the context in which the term is used.

[0052] As used herein, the term "substantially" refers to the complete or nearly complete extent or degree of an action, characteristic, property, state, structure, item, or result. For example, a "substantially" closed object means that the object is completely closed or nearly completely closed. In some cases, the exact degree of deviation from absolute completeness that is permitted may depend on the circumstances. Generally speaking, however, near completion will have the same overall result as if absolute and complete completion were obtained. When used in a negative sense, the use of "substantially" also applies to referring to the complete or nearly complete absence of an action, characteristic, property, state, structure, item, or result.

[0053] As used herein, the term "about" is used to provide flexibility to a numerical value or a range endpoint, and a given value can be "slightly above" or "slightly below" the value or endpoint, depending on the specific circumstances. Unless otherwise specified, the term "about" used in accordance with a specific numerical value or numerical range should also be understood to support such numerical terms or ranges without the term "about". For example, the expression "about 30" should be interpreted as supporting not only values ​​slightly above and slightly below 30, but also the actual numerical value of 30.

[0054] Numerical ranges listed by endpoints include all integers, and where appropriate, include fractions within the range (e.g., 1 to 5 may include 1, 2, 3, 4 when involving, for example, multiple elements, and may also include 1.5, 2, 2.75, and 3.80 when involving, for example, measured values). The description of endpoints also includes the endpoint values ​​themselves (e.g., 1.0 to 5.0 includes 1.0 and 5.0). Any numerical range listed herein is intended to include all subranges contained therein. In addition, the terms first, second, third, etc. in the specification and claims are used to distinguish similar elements, and are not necessarily used to describe continuous or chronological order, unless otherwise specified. It should be understood that the terms used in this manner are interchangeable where appropriate, and the embodiments of the present disclosure described herein can operate in other sequences different from those described or shown herein.

[0055] In this specification, reference may be made to devices, structures, systems, or methods that provide "improved" performance (e.g., increased or decreased results, as the case may be). It should be understood that, unless otherwise stated, such "improvement" is a measure of the benefit obtained based on a comparison with a device, structure, system, or method in the prior art. In addition, it should be understood that the degree of improved performance may vary between the disclosed embodiments, and equality or consistency in the amount, degree, or implementation of improved performance should not be assumed to be universally applicable.

[0056] In addition, embodiments of the present disclosure may include hardware, software, and electronic components or modules, which, for purposes of discussion, may be illustrated and described as if most of the components were implemented only in hardware. However, those skilled in the art will recognize, based on a reading of this detailed description, that in at least one embodiment, the electronic-based aspects of the present invention may be implemented in software (e.g., instructions stored on a non-transitory computer-readable medium) that may be executed by one or more processing units (e.g., microprocessors and / or application-specific integrated circuits). Therefore, it should be noted that the technology of the present disclosure may be implemented using multiple hardware- and software-based devices and multiple different structural components. For example, the "server" and "computing device" described in the specification may include one or more processing units, one or more computer-readable media modules, one or more input / output interfaces, and various connections of connecting components.

[0057] Reference to substituents throughout this specification means that one or more hydrogen atoms on the atom designated in the expression "substituted" are replaced with a group selected from the designated group as detailed below, provided that the normal valence of the designated atom is not exceeded and that the substitution results in a chemically stable compound, i.e., a compound that is sufficiently stable to survive isolation from a reaction mixture.

[0058] The term "halo" or "halogen" as a group or part of a group is a generic term for fluorine (F), chlorine (Cl), bromine (Br), iodine (I).

[0059] The term "alkyl" as a group or part of a group refers to a group of formula C n H 2n+1 wherein n is a number greater than or equal to 1. The alkyl group may be straight or branched and may be substituted as indicated herein. Typically, the alkyl groups disclosed herein contain 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, preferably 1 to 8 carbon atoms, preferably 1 to 6 carbon atoms, and more preferably 1 to 4 carbon atoms. When a subscript is used after a carbon atom, the subscript refers to the number of carbon atoms that the named group may contain. For example, the term "C 1-20 "Alkyl" as a group or part of a group refers to a group of the formula -C n H 2n+1 wherein n is a number from 1 to 20. Thus, for example, "C 1-8 "Alkyl" includes all straight or branched chain alkyl groups having between 1 and 8 carbon atoms, thus including methyl, ethyl, n-propyl, isopropyl, butyl and isomers thereof (e.g., n-butyl, isobutyl and tert-butyl); pentyl and isomers thereof, hexyl and isomers thereof, etc. "Substituted alkyl" refers to an alkyl group substituted with one or more substituents (e.g., 1 to 3 substituents, e.g., 1, 2 or 3 substituents) at any available point of attachment.

[0060] When the suffix "ene" is used in conjunction with an alkyl group, i.e., "alkylene", this refers to an alkyl group as defined herein having two single bonds as points of attachment to other groups. As used herein, the term "alkylene" is also known as "alkanediyl" and, by itself or as part of another substituent, refers to a divalent alkyl group, i.e., having two single bonds for attachment to two other groups. Alkylene groups may be straight or branched and may be substituted as indicated herein. Non-limiting examples of alkylene groups include methylene (-CH2-), ethylene (-CH2-CH2-), methylmethylene (-CH(CH3)-), 1-methylethylene (-CH(CH3)-CH2-), n-propylene (-CH2-CH2-CH2-), 2-methylpropylene (-CH2-CH(CH3)-CH2-), 3-methylpropylene (-CH2-CH2-CH(CH3)-), n-butene (-CH2-CH2-CH2-CH2-), 2-methylbutylene (-CH2-CH(CH3)-CH2-CH2-), 4-methylbutene (-CH2-CH2-CH2-CH(CH3)-), pentyl and its chain isomers, hexyl and its chain isomers.

[0061] The term "alkenyl" as a group or part of a group refers to an unsaturated hydrocarbon group, which may be straight or branched, containing one or more carbon-carbon double bonds. Typically, the alkenyl groups disclosed herein contain 3 to 20 carbon atoms, preferably 3 to 10 carbon atoms, preferably 3 to 8 carbon atoms. When a subscript is used after a carbon atom, the subscript refers to the number of carbon atoms that the named group may contain. 3-20 Examples of alkenyl groups are ethenyl, 2-propenyl, 2-butenyl, 3-butenyl, 2-pentenyl and isomers thereof, 2-hexenyl and isomers thereof, 2,4-pentadienyl and the like.

[0062] The term "cycloalkyl" as a group or part of a group refers to a cyclic alkyl group, i.e., a monovalent saturated hydrocarbon group having one or more ring structures, containing 3 to 20 carbon atoms, more preferably 3 to 10 carbon atoms, more preferably 3 to 8 carbon atoms; more preferably 3 to 6 carbon atoms. Cycloalkyl includes all saturated hydrocarbon groups containing one or more rings, including monocyclic, bicyclic or tricyclic rings. The other rings of a polycyclic cycloalkyl group may be fused, bridged and / or connected by one or more spiro atoms. When a subscript is used after a carbon atom in this document, the subscript refers to the number of carbon atoms that the named group may contain. For example, the term "C 3-20 Cycloalkyl” refers to a cyclic alkyl group containing 3 to 20 carbon atoms. For example, the term “C 3-10 Cycloalkyl” refers to a cyclic alkyl group containing 3 to 10 carbon atoms. For example, the term “C 3-8 Cycloalkyl” refers to a cyclic alkyl group containing 3 to 8 carbon atoms. For example, the term “C 3-6 Cycloalkyl" is a cyclic alkyl group containing 3 to 6 carbon atoms. 3-12 Examples of cycloalkyl include, but are not limited to, adamantyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, bicyclo[2.2.1]hept-2-yl, (1S,4R)-norbornan-2-yl, (1R,4R)-norbornan-2-yl, (1S,4S)-norbornan-2-yl, (1R,4S)-norbornan-2-yl.

[0063] When the suffix "" is used in conjunction with a cycloalkyl group, i.e., cycloalkylene, this refers to a cycloalkyl group as defined herein having two single bonds as points of attachment to other groups. Non-limiting examples of "cycloalkylene" include 1,2-cyclopropylene, 1,1-cyclopropylene, 1,1-cyclobutene, 1,2-cyclobutene, 1,3-cyclopentylene, 1,1-cyclopentylene, and 1,4-cyclohexylene.

[0064] When an alkylene or cycloalkylene group is present, the connection to the molecular structure forming part thereof may be through a common carbon atom or different carbon atoms. To illustrate this, using the asterisk nomenclature of the present disclosure, a C3 alkylene group may be, for example, *-CH2CH2CH2-*, *-CH(-CH2CH3)-*, or *-CH2CH(-CH3)-*. Similarly, a C3 cycloalkylene group may be:

[0065]

[0066] The term "aryl" as a group or part of a group refers to a polyunsaturated aromatic hydrocarbon radical having a single ring (i.e., phenyl) or multiple aromatic rings fused together (e.g., naphthyl), or covalently linked, typically containing 6 to 20 atoms; preferably 6 to 10, wherein at least one ring is aromatic. The aromatic ring may optionally include one or two additional rings (cycloalkyl, heterocyclyl, or heteroaryl) fused thereto. Examples of suitable aryl groups include C 6-20 Aryl, preferably C 6-10 Aryl, more preferably C 6-8 Aryl. Non-limiting examples of aryl groups include phenyl, biphenyl, biphenyl or 1- or 2-naphthyl; 1-, 2-, 3-, 4-, 5- or 6-tetrahydronaphthyl (also known as "1,2,3,4-tetrahydronaphthalene"); 1-, 2-, 3-, 4-, 5-, 6-, 7- or 8-azulyl, 4-, 5-, 6 or 7-indenyl; 4- or 5-indanyl; 5-, 6-, 7- or 8-tetrahydronaphthyl; 1,2,3,4-tetrahydronaphthyl; and 1,4-dihydronaphthyl; 1-, 2-, 3-, 4- or 5-pyrenyl. "Substituted aryl" refers to an aryl group having one or more substituents (e.g., 1, 2 or 3 substituents, or 1 to 2 substituents) at any available attachment point.

[0067] The term "alkoxy" or "alkyloxy" as a group or part of a group refers to a radical having the formula -OR b A group in which R b is an alkyl group as defined above. Non-limiting examples of suitable alkoxy groups include methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, sec-butoxy, tert-butoxy, pentyloxy and hexyloxy.

[0068] The term "heteroalkyl" as a group or part of a group refers to an acyclic alkyl group in which one or more carbon atoms are replaced by at least one heteroatom selected from O, Si, S, B and P, with the proviso that the chain cannot contain two adjacent heteroatoms. This means that one or more -CH3 of the acyclic alkyl group may be replaced by, for example, -OH, and / or one or more -CR2- of the acyclic alkyl group may be replaced by O, Si, S, B and P.

[0069] The term "cyclopentadienyl" as a group or part of a group refers to a group having the formula (V):

[0070]

[0071] Among them, R d ,R e ,R f ,R g ,R h Each independently selected from hydrogen, alkyl, alkenyl, alkoxy or heteroalkyl as defined above. As disclosed herein, cyclopentadienyl is a 5-membered carbocyclic ring that is combined with a metal such as hafnium and / or zirconium by a covalent η5-bond. Therefore, for example, "cyclopentadienyl" refers to hydrogenated cyclopentadiene-2,4-Dean-1-base (Cp) and substituted cyclopentadiene-2,4-Dean-1-base, such as methyl-cyclopentadiene-2,4-Dean-1-base (MeCp), ethyl-cyclopentadiene-2,4-Dean-1-base (EtCp) and n-propyl-cyclopentadiene-2,4-Dean-1-base (n-PrCp).

[0072] The term "aryl" as a group or part of a group refers to a polyunsaturated aromatic hydrocarbon radical having a single ring (i.e., phenyl) or multiple aromatic rings fused together (e.g., naphthyl), or covalently linked, typically containing 6 to 20 atoms; preferably 6 to 10, wherein at least one ring is aromatic. The aromatic ring may optionally include one or two additional rings (cycloalkyl, heterocyclyl, or heteroaryl) fused thereto. Examples of suitable aryl groups include C 6-20 Aryl, preferably C 6-10 Aryl, more preferably C 6-8 Aryl. Non-limiting examples of aryl groups include phenyl, biphenyl, biphenyl or 1- or 2-naphthyl; 1-, 2-, 3-, 4-, 5- or 6-tetrahydronaphthyl (also known as "1,2,3,4-tetrahydronaphthalene"); 1-, 2-, 3-, 4-, 5-, 6-, 7- or 8-azulyl, 4-, 5-, 6 or 7-indenyl; 4- or 5-indanyl; 5-, 6-, 7- or 8-tetrahydronaphthyl; 1,2,3,4-tetrahydronaphthyl; and 1,4-dihydronaphthyl; 1-, 2-, 3-, 4- or 5-pyrenyl. "Substituted aryl" refers to an aryl group having one or more substituents (e.g., 1, 2 or 3 substituents, or 1 to 2 substituents) at any available attachment point.

[0073] In the present disclosure, "gas" may include materials that are gaseous at normal temperature and pressure (NTP), evaporated solids and / or evaporated liquids, and may be composed of a single gas or a gas mixture as appropriate. Gases other than process gases, i.e., gases that are not introduced through a gas distribution assembly, other gas distribution devices, etc., may be used, for example, to seal a reaction space, and may include sealing gases, such as rare gases.

[0074] In some cases, the term "precursor" may refer to a compound that participates in a chemical reaction to produce another compound, particularly a compound that constitutes the membrane matrix or backbone of the membrane; the term "reactant" may be used interchangeably with precursor.

[0075] As used herein, the term "substrate" may refer to any one or more underlying materials that may be used to form or on which a device, circuit, or film may be formed. A "substrate" may be continuous or non-continuous; rigid or flexible; solid or porous; and combinations thereof. A substrate may be in any form, such as a powder, a plate, or a workpiece. Plate-like substrates may include wafers of various shapes and sizes. A substrate may include a bulk material, such as silicon (e.g., single crystal silicon), other Group IV materials, such as germanium, or other semiconductor materials, such as Group II-VI or Group III-V semiconductor materials, and may include one or more layers covering or underlying the bulk material. In addition, the substrate may include various features, such as depressions, protrusions, etc., formed in or on at least a portion of a substrate layer. For example, a substrate may include a bulk semiconductor material and an insulating or (high-k) dielectric material layer covering at least a portion of the bulk semiconductor material.

[0076] As used herein, the terms "film" and / or "layer" may refer to any continuous or discontinuous structure and material, such as materials deposited by the methods disclosed herein. For example, the film and / or layer may include a two-dimensional material, a three-dimensional material, nanoparticles, or even a partial or complete molecular layer or a partial or complete atomic layer or atom and / or molecular clusters, or a layer composed of isolated atoms and / or molecules. The film or layer may include a material or layer having pinholes, which may be continuous or discontinuous.

[0077] In the present disclosure, the following abbreviations of chemical structures are used: Cp represents cyclopentadienyl, Me represents methyl; Et represents ethyl; n-Pr represents n-propyl; i-Pr represents isopropyl or isopropyl, n-Bu represents n-butyl; t-Bu represents tert-butyl or tert-butyl.

[0078] Turning now to the accompanying drawings, Figure 1A method 100 according to an exemplary embodiment of the present disclosure is shown. In general, the technology disclosed herein relates to the field of capacitor devices, and more specifically, to a method for forming a capacitor structure including a doped HZO layer that exhibits a high dielectric constant value κ within a specific voltage range. The important steps in the formation of the doped HZO layer mentioned here can include selecting an appropriate dopant precursor that includes three or four valence electrons and whose atomic radius is smaller than the atomic radius of the Hf or Zr elements of the HZO layer. Advantageously, the inventors have found that the method disclosed herein allows the CV curve to be changed, resulting in a dielectric constant value κ at a desired high level and within a desired voltage range while still experiencing low leakage. In detail, one challenge in doped HZO layers, especially when used in MIM CAPS, is to push the ferroelectric HZO into antiferroelectric conduction, which increases the dielectric constant κ at a desired voltage, thereby shifting the CV curve so that high κ can be achieved at a desired voltage. Compared to the prior art, the present disclosure allows designing a doped HZO layer by using appropriate dopants so that the ferroelectric properties of the HZO layer are changed to a predominantly tetragonal composition, thereby moving the maximum dielectric constant κ to the region of interest, which increases the dielectric constant κ in the desired region compared to the undoped HZO layer.

[0079] As explained in more detail below, various embodiments of the present disclosure are directed to a method of forming a doped hafnium zirconium oxide (HZO) layer on a substrate, the method comprising the steps of:

[0080] a) providing the substrate in a reaction chamber;

[0081] b) executing one or more loops, the loops comprising:

[0082] i. a hafnium precursor pulse, wherein at least a portion of the substrate is contacted with one or more hafnium precursors by introducing the one or more hafnium precursors into the reaction chamber;

[0083] ii. a zirconium precursor pulse, wherein at least a portion of the substrate is contacted with one or more zirconium precursors by introducing the one or more zirconium precursors into the reaction chamber;

[0084] iii. an oxygen reactant pulse, wherein at least a portion of the substrate is contacted with one or more oxygen reactants by introducing the one or more oxygen reactants into the reaction chamber; and

[0085] iv. a dopant precursor pulse, wherein at least a portion of the substrate is contacted with one or more dopant precursors by introducing the one or more dopant precursors into the reaction chamber,

[0086] Thereby forming a doped HZO layer;

[0087] The dopant precursor includes a dopant element characterized by having three or four valence electrons and an atomic radius smaller than the atomic radius of the Hf or Zr element of the HZO layer.

[0088] Figure 1 An exemplary embodiment of the above method for forming a doped hafnium zirconium oxide (HZO) layer on a substrate is described. The method begins at 110 by providing a substrate 111 in a reaction chamber. The cyclic deposition process includes contacting a hafnium precursor with at least a portion of the substrate in a hafnium precursor pulse 112. Optionally, after the hafnium precursor pulse 112, the reaction chamber 113 is purged. Then, a zirconium precursor is provided to the reaction chamber in a zirconium precursor pulse 114. Optionally, after the zirconium precursor pulse, the reaction chamber 115 can be purged. In addition, the cyclic deposition process includes providing an oxygen reactant pulse 116 to the reaction chamber. Optionally, after the oxygen reactant pulse, the reaction chamber 117 can be purged. Then, a dopant precursor is provided to the reaction chamber in a dopant precursor pulse 118. Optionally, after the dopant precursor pulse, the reaction chamber 119 can be purged. The hafnium precursor pulse 112, the zirconium precursor pulse 114, the oxygen reactant pulse 116, the dopant precursor pulse 118, and the optional purges 113, 115, 117, 119 may be repeated 121 any number of times in any order. Figure 1 In some cycles of the method shown, one or more precursors (e.g., hafnium precursor pulse 112, zirconium precursor pulse 114, oxygen reactant pulse 116, dopant precursor pulse 116, dopant precursor pulse 118, and optional purges 113, 115, 117, 119) may be omitted to obtain a doped HZO layer having a desired thickness. When a doped HZO-containing layer having a desired thickness has been deposited, the method ends 120. Once the method ends, the substrate may, for example, undergo additional processing to form a device structure and / or device.

[0089] Specifically, forming a doped HZO layer on a substrate as described herein involves a cyclic deposition process, such as an atomic layer deposition (ALD) process or a cyclic chemical vapor deposition process. ALD is a thin film technology for forming an extremely thin and precise layer of material on a substrate, so that a uniform and well-controlled layer can be formed on a three-dimensional surface. This cyclic deposition process may include one or more cycles, whereby these steps may be repeated for at least 1 cycle to at most 1000 cycles, or at least 2 cycles to at most 100 cycles, or at least 5 cycles to at most 50 cycles. The skilled person understands that different orders of pulses within a cycle are possible.

[0090] As used herein, the term "deposition" or "cyclic deposition" or "cyclic deposition process" or "cyclic deposition process" refers to the sequential introduction of precursors into a reaction chamber to deposit a layer or film on a substrate, and includes processing techniques such as atomic layer deposition (ALD), cyclic chemical vapor deposition (cyclic CVD), and hybrid cyclic deposition processes including an ALD component and a cyclic CVD component. The term "atomic layer deposition" (ALD) refers to a vapor deposition process in which a deposition cycle (typically a plurality of consecutive deposition cycles) is performed in a processing chamber. 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, organometallic MBE, and chemical beam epitaxy when performed with alternating pulses of precursor / reactive gas and purge gas (e.g., inert carrier gas). Typically, for an ALD process, during each cycle, a (metal) precursor is introduced into a reaction chamber and chemically adsorbed onto a deposition surface (e.g., a substrate surface that may include previously deposited material or other material from a previous ALD cycle) and forms a material, such as approximately a monolayer or sub-monolayer of material, or several monolayers of material, or multiple monolayers of material, that is not susceptible to reaction with additional precursors (i.e., a self-limiting reaction). Thereafter, in some cases, a reactant (e.g., another precursor or a reactive gas) may subsequently be introduced into the process chamber for converting the chemically adsorbed precursor into the desired material on the deposition surface. The reactant is capable of further reacting with the precursor. During one or more repetitions, such as during each deposition step, a purge step may be utilized to remove any excess precursor from the process chamber and / or any excess reactant and / or reaction byproducts from the reaction chamber. Note that, as used herein, an ALD process does not necessarily include a series of self-limiting surface reactions. Advantageously, the method disclosed herein allows the formation of a dipole layer that does not require full film closure to work. Thus, faster deposition is allowed with greater error tolerance than disclosed in the prior art.

[0091] In a preferred embodiment, the deposition process disclosed herein refers to an atomic layer deposition process. Typically, a deposition cycle can form a film or layer of about 0.10nm. However, the experimental thickness can vary depending on the amount and type of the cycle and the reaction sites available on the substrate. In a preferred embodiment, the method disclosed herein provides that the HZO layer has an average thickness of 1nm or less, or 0.75nm or less, preferably 0.50nm or less, or 0.4nm or less, or 0.3nm or less, preferably 0.25nm or less, or 0.2nm or less, more preferably 0.10nm or less. In some embodiments, the HZO layer grows at a rate of 0.10nm or less per alternating precursor / reactive gas and purge gas (e.g., inert carrier gas) pulse.

[0092] To produce a doped HZO layer on a substrate, a first pulse with a hafnium precursor, a second pulse with a zirconium precursor, and a third pulse with an oxygen reactant are introduced into a reaction chamber such that at least a portion of the substrate is contacted with the hafnium precursor, the zirconium precursor, the oxygen reactant, and / or the dopant precursor to form the desired film. The precursor pulses typically last from at least 0.01 seconds to at most 120 seconds, while the oxygen reactant pulses last from at least 0.1 seconds to at most 20 seconds. One precursor will typically react with the substrate surface while the other precursor remains inert during the reaction. In repeated deposition cycles, one precursor is introduced at a time, allowing them to react with the surface in a self-limiting manner. When the first precursor is introduced, it reacts with the substrate surface to form a chemically adsorbed layer. Typically, excess precursor is purged or removed from the reaction chamber before the next precursor is introduced, which will then react with the already formed chemically adsorbed layer from the previous step to form a new layer. Once all available reaction sites on the substrate surface are saturated, the reaction stops and the film forms, growing atom by atom, ensuring precise control of film thickness.

[0093] In order to develop a material having linear CV characteristics and a dielectric constant κ value greater than 40 within a specific voltage range, a dopant precursor pulse is added to the reaction chamber so that at least a portion of the substrate is in contact with one or more dopant precursors, thereby forming a doped HZO layer. Therefore, this doped HZO layer is a material layer formed of hafnium oxide (HfO2) on a substrate, which has been intentionally modified or doped with certain elements or impurities. Doping involves introducing small amounts of specific atoms or ions into the crystal lattice of the host material. This modification can change the electrical, optical or other properties of the material to accommodate the desired function. When dopants are used to improve electrical performance, typically, the dielectric constant value κ is increased, as well as reducing current leakage and improving its interference with other materials, such as in semiconductor devices.

[0094] When a dopant precursor including a dopant element having three or four valence electrons and an atomic radius smaller than that of the Hf or Zr element of the HZO layer is used, the HZO material can be pushed into an appropriate morphotropic phase boundary (MPB). Therefore, doping the HZO layer with a small ionic radius element stabilizes the tetragonal phase of the HZO layer, so that a morphotropic phase boundary (MPB) is reached between the orthorhombic phase and the tetragonal phase of the HZO layer to allow the polarization switching voltage of the HZO layer to be changed. With a certain percentage of dopants added, the material adopts a composition that is mainly a tetragonal phase, which causes the dielectric constant value κ of the HZO layer to peak in the voltage region of interest. In addition, changing the polarization switching voltage of the HZO layer changes the capacitance-voltage (CV) linearity of the HZO layer, thereby adjusting the shape of the capacitance-voltage (CV) curve and achieving better linearity. Ideally, the dielectric constant value (κ) of the doped HZO layer is higher than 35 at about -2 and -3 MV / cm.

[0095] The MPB is a compositional region in a material's phase diagram where the crystal structure and properties change dramatically as the material's composition changes. Different crystal structures can exhibit different electrical, mechanical, and thermal properties. The MPB represents a compositional range where two different crystalline phases coexist, and relatively small changes in composition can lead to significant changes in the material's properties. Ferroelectric, antiferroelectric, and paraelectric phases are different phases of the MPB, and each has a different crystal ordering within these materials. These phases are related to how the electric dipoles in the material are arranged or ordered, which in turn affects their electrical, mechanical, and thermal properties. In ferroelectric materials, electric dipoles are an arrangement of molecules or atoms with separated positive and negative charges that can spontaneously align in a particular direction even in the absence of an external electric field. This arrangement produces a permanent electric polarization that can be reversed when an external electric field is applied in the opposite direction.

[0096] In an antiferroelectric material, adjacent dipoles align in opposite directions, meaning the material has a net polarization of zero. When an external electric field is applied, the dipoles tend to align in a direction opposite to that of the field. Antiferroelectric materials are characterized by abrupt changes in their polarization.

[0097] In paraelectric materials, there is no spontaneous polarization at all. However, when an external electric field is applied, the material becomes temporarily polarized. When the field is removed, the polarization disappears. Paraelectric materials exhibit a linear relationship between polarization and electric field and are therefore often used as dielectric materials in capacitors.

[0098] These different phases can exist in certain materials due to the arrangement of their atoms or molecules and the interactions between them. Phase transitions between these different states can have a profound effect on the material's properties, and understanding and controlling these phase transitions is crucial when designing capacitors and using these materials for a variety of applications.

[0099] Therefore, when the HZO layer is doped with a precise concentration of a selected element, an antiferroelectric / paraelectric phase boundary can be triggered and an appropriate crystal structure can be obtained. The inventors surprisingly found that when a doped HZO layer is produced using a dopant element having three or four valence electrons and an atomic radius smaller than the atomic radius of the Hf or Zr elements of the HZO layer, a main tetragonal phase composition is triggered in the formed material. As a result, the main or primary crystal structure of the material is tetragonal, whereby the crystal has three axes of different lengths, two of which are equal and perpendicular to each other, the third is longer or shorter, and the angles between the axes are all right angles. By doping the HZO layer with such a dopant precursor, a main tetragonal phase composition of the HZO layer will appear, which allows a shift in the maximum dielectric constant value κ, so that a peak of the value κ is achieved in the region of interest, and an almost flat CV characteristic will be present. Figure 2a-2c Different possible modifications of the CV curves by doping the HZO layer are shown. Figure 2aIn the embodiment of the present invention, a first type of dopant is used to improve the CV curve of the undoped HZO layer 210. By doing so, the shape of the CV curve of the doped HZO layer 220 remains essentially the same, however an increase in the value κ is achieved at approximately the same voltage. The inventors have found that, for example, using Al as a dopant can produce this effect. Doping the HZO layer with an Al dopant precursor has the effect of reducing the non-polar phase due to the formation of oxygen vacancies and obtaining a MPB having a composition of about 50%-50% orthorhombic and tetragonal phases. The dopant precursor is preferably of the general formula Al(R 1 )3 represents a low-reactivity aluminum precursor, wherein each R 1 are independently selected from hydrogen, halogen, alkyl, alkenyl, N(R 2 )2, cycloalkyl and alkoxy; and wherein each R 2 Selected from hydrogen, alkyl or alkenyl. Alternatively, using Ge as a dopant for the Zr-rich HZO layer has a similar effect.

[0100] exist Figure 2b In the embodiment of the present invention, a second type of dopant is used to stretch the CV curve of the undoped HZO layer 210. By doing so, the shape of the CV curve of the doped HZO layer 230 is changed so that the peak moves to a higher field while reducing the maximum value of κ. The inventors have found that this effect can be produced by using Si as a dopant, for example. Doping the HZO layer with a Si dopant precursor has the effect of increasing the barrier between the tetragonal phase and the polar state. The increase in the tetragonal phase is due to the effects of strain and smaller electronegativity, which makes lattice polarization more difficult. This results in moderately high κ values ​​being achieved at voltages different from those of the undoped HZO layer. The dopant precursor is preferably selected from silicon tetraacetate (Si(OOCCH3)4) and Si(R 3 )4, wherein each R 3 are independently selected from hydrogen, halogen, alkyl, alkenyl, N(R 4 )2, cycloalkyl and alkoxy, and each R 4 Selected from hydrogen, alkyl or alkenyl. Alternatively, using Ge as a dopant for the Zr-rich HZO layer has a similar effect.

[0101] In some examples, the use of dopants such as Al, Si, and / or Ge in the HZO layer can have a combination of the above effects on the CV curve.

[0102] Silicon doping of HZO is very beneficial when using 2.0 to 4.5% doping. The percentage of silicon doping is calculated as follows:

[0103] Doping % = Si / (Si+Hf+Zr)*100

[0104] To achieve these concentrations, low-reactivity Si precursors including, but not limited to, tris(dimethylamino)silane (TDMAS) may be used. However, such precursors may also be known to have poor nucleation, which means that upon doping, complete / uniform coverage of the wafer may not be achieved, resulting in wafer-to-wafer and wafer-to-wafer variations. A multiple rapid pulse scheme with TDMAS pulses is proposed to improve the repeatability of Si doping of HZO. By utilizing repeated micropulses of the TDMAS precursor during the dopant pulse step, a good distribution of surface silicon can be obtained despite poor nucleation. Because the absorption of the Si precursor can be self-limiting as long as the operating temperature remains below the decomposition temperature of TDMAS, no excessive silicon doping occurs under these multiple rapid pulses, while better nucleation and surface coverage are achieved. In this way, in addition to wafer-to-wafer silicon doping uniformity, increased wafer-to-wafer reproducibility is achieved in Si-doped HZO.

[0105] Furthermore, silicon precursors based on water as a co-reactant and water-based processes can be easily incorporated into a water-based HfO2 ALD process. While water has many advantages, co-reactants such as O3, O2, and H2O2 can also be used. Examples of such water-based silicon precursors are tetraacetic acid silicon (Si(OOCCH3)4) and Si(R 3 )4. These precursors take advantage of the high reactivity with water and combined with the ALD process for SiO2, will ensure successful incorporation into the HfO2-based ALD process. Various sub-cycles of Si or Hf will adjust the ratio of these elements in the final film. The deposition temperature can be 150-450°C, with a more optimized range of about 300°C. In addition, post-deposition annealing may be required to obtain certain film properties, such as positive phase for dielectric or iron-based films.

[0106] exist Figure 2c In the embodiment of the present invention, a third type of dopant is used to shift the CV curve of the undoped HZO layer 210. By doing so, the shape of the CV curve of the doped HZO layer 240 remains approximately the same, while the peak moves to a higher field while still maintaining the maximum value of κ. The inventors have discovered that the introduction of a low ionic radius dopant such as Ge can produce this effect. Doping the HZO layer with a Ge dopant precursor has the effect that the material is forced to adopt a predominantly tetragonal phase composition due to the generation of strain and the increase in polar lattice due to the higher electronegativity. This will cause the maximum peak of the κ value to move to a different region and promote better linearity. The dopant precursor is preferably of the general formula Ge(R 5 )4 represented by a low-reactivity germanium precursor, wherein each R 5 are independently selected from hydrogen, halogen, alkyl, alkenyl, N(R 6 )2, cycloalkyl and alkoxy; and wherein each R 6is selected from hydrogen, alkyl or alkenyl. However, it should be noted that the present disclosure is not limited to silicon or germanium dopants, and other II-VI group elements (such as carbon, phosphorus, arsenic, boron, indium, nickel or antimony) may also be used.

[0107] The inventors surprisingly found that a HZO layer having a higher percentage of Zr, preferably in the range of 60% to 80% Zr, and doped with a lower percentage of Ge, less than about 3%, or less than about 2%, or less than about 1.5%, or between about 0.25% and 1.5% Ge, can be advantageous for enhancing a higher κ phase in the voltage region of interest while being less sensitive to the thickness and composition of the HZO layer. In one example, a metal oxide and ozone based HZO process (MO-O3) with germanium doping (e.g., regarding Figure 1 The invention relates to a material stack including a HZO layer having a thickness sufficient to form a crystalline structure rather than maintaining an amorphous structure. In some examples, the thickness of the HZO layer is found to be greater than or equal to 45 angstroms. However, other thicknesses are possible, and claimed subject matter is not limited in this respect. Figure 3 The exemplary MIM CAP 300 shown may include a top electrode made of titanium nitride (TiN) deposited by atomic layer deposition (ALD). In some examples, a thermal budget greater than about 400°C can achieve a capacitance-area density (C / A) greater than 70fF / um2, and in some examples greater than 100fF / um2. This C / A can be achieved by applying a negative bias in the range of about -1.5V to about -1.0V or applying a positive bias in the range of about 1.5V to about 1.0V, where about + / -0.25V is represented. Using the above method, C / A far greater than 100fF / um2 can be achieved, and the claimed subject matter is not limited thereto.

[0108] When doping the HZO layer with a specific dopant, the κ value will change, which will affect the dielectric constant of the material. The higher the κ value, the better the capacitor's ability to store electrical energy in an electric field. In order to maximize the charge that the capacitor can hold, the insulator material used as the doped HZO layer needs to have as high a dielectric constant as possible, while also having as high a breakdown voltage as possible and as low a frequency loss as possible. Therefore, depending on the final requirements of the doped HZO layer, changes in the thickness of the HZO layer, the selected dopant element such as Al, Si or Ge, changes in the percentage of the dopant element used, and the environmental settings when producing the doped HZO layer can provide the maximum κ value achieved and changes in CV characteristics such as stretched or offset CV curves.

[0109] Typically, the cycle includes three or more pulses. In some embodiments, at least one pulse involves a self-limiting surface reaction. In some embodiments, all pulses involve self-limiting surface reactions. In some embodiments, an oxygen reactant pulse is performed after each hafnium precursor pulse and / or after each zirconium precursor pulse. The use of an oxygen reactant pulse after a precursor pulse allows a thin film to be produced on a provided substrate. After the introduction of a precursor pulse, it is important to ensure that any excess or unreacted precursor is removed from the reaction chamber before the next reactant is introduced. By doing so, an undesirable accumulation of precursor molecules is prevented, which would otherwise result in undesirable film properties or film inhomogeneities. Since the precursor pulse also involves chemical adsorption, in which the precursor molecules will adsorb onto and react with the substrate surface, providing an oxygen reactant pulse will help complete the surface reaction and promote the formation of the desired film on the substrate, help remove any residual adsorbed precursor molecules and reduce the presence of impurities and defects in the formed film.

[0110] In some embodiments, the dopant precursor pulse is performed after the hafnium precursor pulse without any intermediate oxygen reactant pulse. In the hafnium precursor pulse, the hafnium precursor is provided to the reaction chamber. In the dopant precursor pulse, the dopant compound is provided to the reaction chamber. Thus, a thin film is formed on at least a portion of the substrate comprising hafnium and the dopant. In some embodiments, the dopant precursor pulse is performed after the zirconium precursor pulse without any intermediate oxygen reactant pulse. In the zirconium precursor pulse, the zirconium precursor is provided to the reaction chamber. In the dopant precursor pulse, the dopant compound is provided to the reaction chamber. Thus, a thin film is formed on at least a portion of the substrate comprising at least zirconium and the dopant.

[0111] It should be understood that any two steps and / or pulses can be separated by a purge. Thus, in some embodiments, the step of contacting one or more precursors and / or the step of contacting a dopant compound are separated by a purge. In some embodiments, subsequent cycles are separated by a purge.

[0112] In certain embodiments, the methods disclosed herein provide one or more cycles comprising the steps of contacting one or more precursors with at least a portion of a substrate and providing a nitrogen compound or another inert gas into a reaction chamber, the cycles being quasi oxygen-free, and preferably completely oxygen-free. More specifically, the disclosed methods provide deposition of HZO films free of oxygen contaminants, thereby reducing the dipole equivalent oxide thickness (EOT) and the number of deposition defects.

[0113] In some embodiments, the hafnium precursor pulse, zirconium precursor pulse, oxygen reactant pulse, and / or dopant precursor pulse include multiple micropulses. Micropulsing is a technique used to maintain fine control over thin film growth, composition, and desired properties. Micropulsing involves the precisely timed delivery of very short pulses of precursor or reactant gases and allows for better utilization of precursor materials. By delivering small, controlled amounts of precursor, it can be ensured that most of the precursor molecules are chemically absorbed and able to react with the substrate. This is particularly valuable in processes that require precise atomic or molecular layer deposition and where avoiding excessive precursor exposure is critical to achieving desired film properties, such as in the case of MIM CAPS with a peak in κ in the voltage region of interest.

[0114] Non-limiting examples of dopant elements may include aluminum, silicon, nickel, germanium, gallium, and carbon.

[0115] In a specific embodiment, the method disclosed herein provides a variation in the concentration of the dopant element in the HZO layer. The concentration of the dopant element ranges between 0.50% and 8.0% relative to the dopant element concentration, more particularly between 1.0% and 5.0% relative to the dopant element concentration, and even more particularly between 2.0% and 4.50% relative to the dopant element concentration.

[0116] Alternatively, the molar atomic concentration of the dopant element is between 0.50 atomic % and 15.0 atomic %, more particularly between 0.50 atomic % and 10.0 atomic %, more particularly between 1.0 atomic % and 5.0 atomic %, and more particularly between 2.00 atomic % and 4.50 atomic %. Preferably, the dopant element comprises a molar atomic percentage of less than 10.0 atomic %, such as less than 9.0 atomic %, or less than 8.0 atomic %, or less than 7.0 atomic %, or less than 6.0 atomic %, or less than 5.0 atomic %, or less than 4.0 atomic %, or less than 3.0 atomic %, or less than 2.0 atomic %, or less than 1.0 atomic %, or less than 0.5 atomic %.

[0117] In a particular embodiment, the dopant element is Al. In addition, the dopant precursor is a low-reactivity precursor, preferably composed of the general formula Al(R 1 )3 represents a low-reactivity aluminum precursor, wherein each R 1 are independently selected from hydrogen, halogen, alkyl, alkenyl, N(R 2 )2, cycloalkyl and alkoxy; and wherein each R 2 is selected from hydrogen, alkyl or alkenyl.

[0118] In a preferred embodiment, each R 1 are independently selected from hydrogen, halogen, C 1-8 Alkyl, C 2-8 Alkenyl, C3-8 Cycloalkyl and C 1-8 alkoxy; and each R 2 Selected from hydrogen, C 1-8 Alkyl or C 2-8 Alkenyl.

[0119] In a more preferred embodiment, each R 1 are independently selected from hydrogen, halogen, C 1-4 Alkyl, C 2-4 Alkenyl, C 3-8 Cycloalkyl and C 1-4 alkoxy; and each R 2 Selected from hydrogen, C 1-4 Alkyl or C 2-4 Alkenyl.

[0120] In certain embodiments, the aluminum precursor is selected from aluminum hydride (AlH3), aluminum trifluoride (AlF3), aluminum trichloride (AlCl3), aluminum tribromide (AlBr3), aluminum triiodide (AlI3), trimethylaluminum (Al(CH3)3), triethylaluminum (Al(C2H5)3), triisopropylaluminum (Al(CH3)3), i Pr)3), tetra-n-butylaluminum (Al(C4H9)3), tetra-tert-butylaluminum (Al(O t Bu)3), aluminum methoxide (Al(OCH3)3), aluminum ethoxide (Al(OC2H5)3), aluminum isopropoxide (Al(O i Pr)3), aluminum n-butoxide (Al(OC4H9)3) and aluminum tert-butoxide (Al(O t Bu)3).

[0121] In a specific embodiment, the dopant element is Si. In addition, the dopant precursor is a low-reactivity precursor, which is preferably selected from tetraacetic acid silicon (Si(OOCCH3)4) and Si(R 3 )4, wherein each R 3 are independently selected from hydrogen, halogen, alkyl, alkenyl, N(R 4 )2, cycloalkyl and alkoxy; and wherein each R 4 is selected from hydrogen, alkyl or alkenyl. In a preferred embodiment, each R 3 are independently selected from hydrogen, halogen, C 1-8 Alkyl, C 2-8 Alkenyl, C 3-8 Cycloalkyl and C 1-8 alkoxy; and each R 4 Selected from hydrogen, C 1-8 Alkyl or C 2-8 Alkenyl.

[0122] In a more preferred embodiment, each R 3are independently selected from hydrogen, halogen, C 1-4 Alkyl, C 2-4 Alkenyl, C 3-8 Cycloalkyl and C 1-4 alkoxy; and each R 4 Selected from hydrogen, C 1-4 Alkyl or C 2-4 Alkenyl.

[0123] In a specific embodiment, the silicon precursor is selected from silane (SiH4), silicon tetrafluoride (SiF4), silicon tetrachloride (SiCl4), silicon tetrabromide (SiBr4), silicon tetraiodide (SiI4), tetramethylsilane (Si(CH3)4), tetraethylsilane (Si(C2H5)4), tetra(isopropyl)silane (Si( i Pr)4), tetra-n-butylsilane (Si(C4H9)4), tetra-tert-butylsilane (Si(O t Bu)4), tetramethoxysilane (Si(OCH3)44), tetraethoxysilane (Si(OC2H5)4), tetra(isopropoxy)silane (Si(O i Pr)4), tetra-n-butoxysilane (Si(OC4H9)4), tetra-tert-butoxysilane (Si(O t Bu)4) and tris(dimethylamino)silane (Si(N[CH3]2)3).

[0124] In a particular embodiment, the dopant element is Ge. In addition, the dopant precursor is a low-reactivity precursor, preferably having the general formula Ge(R 5 )4 represented by a low-reactivity germanium precursor, wherein each R 5 are independently selected from hydrogen, halogen, alkyl, alkenyl, N(R 6 )2, cycloalkyl and alkoxy; and wherein each R 6 is selected from hydrogen, alkyl or alkenyl.

[0125] In a preferred embodiment, each R 5 are independently selected from hydrogen, halogen, C 1-8 Alkyl, C 2-8 Alkenyl, C 3-8 Cycloalkyl and C 1-8 alkoxy; and each R 6 Selected from hydrogen, C 1-8 Alkyl or C 2-8 Alkenyl.

[0126] In a more preferred embodiment, each R 5 are independently selected from hydrogen, halogen, C 1-4 Alkyl, C 2-4 Alkenyl, C 3-8 Cycloalkyl and C 1-4 alkoxy; and each R6 Selected from hydrogen, C 1-4 Alkyl or C 2-4 Alkenyl.

[0127] In a specific embodiment, the germanium precursor is selected from germanium (GeH4), germanium tetrafluoride (GeF4), germanium tetrachloride (GeCl4), germanium tetrabromide (GeBr4), germanium tetraiodide (GeI4), tetramethylgermanium (Ge(CH3)4), tetraethylgermanium (Ge(C2H5)4), tetra(isopropyl)germanium (Ge( i Pr)4), tetra-n-butylgermanium (Ge(C4H9)4), tetra-tert-butylgermanium (Ge(O t Bu)4), tetramethoxygermanium (Ge(OCH3)4), tetraethoxygermanium (Ge(OC2H5)4), tetra(isopropoxy)germanium (Ge(OC3H7)4), tetra-n-butoxygermanium (Ge(OC4H9)4), tetra-tert-butoxygermanium (Ge(O t The inventors surprisingly found that HZO layers doped with Ge, Si and / or Al can be particularly advantageous for forcing the layer to adopt a predominantly tetragonal phase composition, thereby moving the maximum κ peak to the voltage region of interest while promoting better linearity.

[0128] Low-reactivity precursors are compounds with limited reactivity under certain conditions. In thin film deposition techniques such as ALD, low-reactivity precursors are precursor compounds that do not readily chemically react or decompose at low temperatures or under deposition process conditions.

[0129] In the described methods, the goal is to deposit thin films in a controlled and uniform manner. The use of low-reactivity precursors may be desirable because such precursors allow for precise control of film growth without premature reaction or decomposition on the substrate surface.

[0130] In addition, low-reactivity precursors are particularly useful when the deposition process needs to be performed at a temperature compatible with the substrate and the desired film properties. Because the reactivity of low-reactivity precursors can be adjusted by changing processing conditions such as temperature, pressure, and exposure time, small changes can change the reactivity of low-reactivity precursors to suit specific deposition processes, materials, and desired film properties.

[0131] In certain embodiments, the methods disclosed herein provide that the hafnium precursor is represented by the following general formula (I),

[0132]

[0133] Among them, Q 1 ,Q 2 ,Q 3 ,Q 4are independently selected from halogen, alkyl, alkenyl, N(R 7 )2, alkoxy, heteroalkyl, cycloalkyl, aryl and cyclopentadienyl; and wherein each R 7 is independently hydrogen, alkyl or alkenyl.

[0134] In some embodiments, the present disclosure provides that Q 1 ,Q 2 ,Q 3 ,Q 4 are each independently selected from halogen, C 1-8 Alkyl, C 2-8 Alkenyl, N(R 7 2. C 1-8 Alkoxy, heterocyclic C 1-8 Alkyl, C 3-8 Cycloalkyl, C 6-10 aryl and cyclopentadienyl; wherein each R 7 are independently hydrogen, C 1-8 Alkyl or C 2-8 Alkenyl.

[0135] In some embodiments, the present disclosure provides that Q 1 ,Q 2 ,Q 3 ,Q 4 are each independently selected from halogen, C 1-4 Alkyl, C 2-4 Alkenyl, N(R 7 2. C 1-4 Alkoxy, heterocyclic C 1-4 Alkyl, C 3-8 Cycloalkyl, C 6-10 aryl and cyclopentadienyl; wherein each R 7 are independently hydrogen, C 1-4 Alkyl or C 2-4 Alkenyl.

[0136] In certain embodiments, the methods disclosed herein provide that the hafnium precursor is selected from the group consisting of HfCl4, HfBr4, HfI4, HfMe4, HfEt4, Hf(nPr)4, Hf(iPr)4, Hf(nBu)4, Hf(tBu)4, Hf(NMe2)4, Hf(NEt2)4, Hf[MeEtN]4, HfCp[(NMe2)3], Hf(OMe)4, Hf(OEt)4, Hf(OnPr)4, Hf(OiPr)4, Hf(OnBu)4, Hf(OtBu)4, Hf[(CpMe)2][OMe][Me], Hf[(CpMe)2][(Me)2], tetrakis(1-methoxy-2-methyl-2-propoxy)hafnium (Hf(mmp)4).

[0137] Using hafnium precursors when depositing thin films on substrates typically results in hafnium-based materials with a high dielectric constant, κ, compared to traditional silicon dioxide (SiO2), enabling better control of gate leakage and improved device performance.

[0138] In certain embodiments, the methods disclosed herein provide that the zirconium precursor is represented by the following general formula (II),

[0139]

[0140] Among them, Q 5 ,Q 6 ,Q 7 ,Q 8 are independently selected from halogen, alkyl, alkenyl, N(R 8 )2, alkoxy, heteroalkyl, cycloalkyl, aryl and cyclopentadienyl; wherein each R 8 is independently hydrogen, alkyl or alkenyl.

[0141] In some embodiments, the present disclosure provides that Q 5 ,Q 6 ,Q 7 ,Q 8 are each independently selected from halogen, C 1-8 Alkyl, C 2-8 Alkenyl, N(R 8 2. C 1-8 Alkoxy, heterocyclic C 1-8 Alkyl, C 3-8 Cycloalkyl, C 6-10 aryl and cyclopentadienyl; wherein each R 8 are independently hydrogen, C 1-8 Alkyl or C 2-8 Alkenyl.

[0142] In some embodiments, the present disclosure provides that Q 5 ,Q 6 ,Q 7 ,Q 8 are each independently selected from halogen, C 1-4 Alkyl, C 2-4 Alkenyl, N(R 8 2. C 1-4 Alkoxy, heterocyclic C1-4 Alkyl, C 3-8 Cycloalkyl, C 6-10 aryl and cyclopentadienyl; wherein each R 8 are independently hydrogen, C 1-4 Alkyl or C 2-4 Alkenyl.

[0143] In certain embodiments, the methods disclosed herein provide that the zirconium precursor is selected from the group consisting of ZrCl4, ZrBr4, ZrI4, ZrMe4, ZrEt4, Zr(nPr)4, Zr(iPr)4, Zr(nBu)4, Zr(tBu)4, Zr(NMe2)4, Zr(NEt2)4, Zr[MeEtN]4, ZrCp[(NMe2)3], Zr(OMe)4, Zr(OEt)4, Zr(OnPr)4, Zr(OiPr)4, Zr(OnBu)4, Zr(OtBu)4, Zr[(CpMe)2][OMe][Me], Zr[(CpMe)2][(Me)2], tetrakis(1-methoxy-2-methyl-2-propoxy)zirconium (Zr(mmp)4).

[0144] Compared to traditional silicon dioxide (SiO2), the use of zirconium precursors when depositing thin films on substrates generally results in zirconium-based materials with a high dielectric constant, κ, which helps maintain gate capacitance while reducing gate oxide thickness in scaled-down applications. In addition, zirconium precursors are used to create barrier coatings in microelectronics to prevent metal diffusion into dielectric layers, thereby enhancing the reliability and performance of interconnect structures.

[0145] In certain embodiments, the methods disclosed herein provide a decomposition temperature of the dopant precursor that is higher than the operating temperature at which the doped hafnium zirconium oxide (HZO) layer is formed. The decomposition temperature refers to the temperature at which the precursor molecules decompose or chemically react to cause the dopant material to be deposited on the substrate surface. When a dopant precursor is used in a thin film deposition process such as ALD, the decomposition temperature of the dopant precursor is a key parameter. If the precursor decomposes at a temperature significantly lower than the processing temperature, premature decomposition may occur in the gas phase, resulting in the deposition of unexpected reaction byproducts and poor film quality. In addition, the decomposition of the precursor at an appropriate temperature ensures that the dopant material is deposited in its desired form without introducing impurities or producing defective films. However, if the precursor decomposes at too high a temperature, it may not completely decompose on the substrate surface, resulting in incomplete film growth and waste of precursor.

[0146] Therefore, in certain embodiments, the methods disclosed herein provide that the operating temperature for forming the doped HZO layer is between 150°C and 450°C, preferably between 250°C and 350°C, and more preferably around 300°C.

[0147] In certain embodiments, the method disclosed herein further provides that the substrate includes a metal oxide (MO) surface layer, and / or wherein the method further includes a step of forming a metal oxide (MO) top layer on the doped HZO layer, thereby forming a layered doped HZO structure. In addition, the MO surface layer and / or the MO top layer are in direct contact with the doped HZO layer. The metal oxide is preferably TiO2.

[0148] Figure 3 An exemplary MIM CAPS 300 of the present disclosure is shown, consisting of two metal layers or electrodes 312, 316, separated by an insulator layer or dielectric 314 and a substrate 310 that holds the two metal layers 312, 316 and the insulator layer 314. The insulator layer 314 is formed by Figure 1 A method for forming a doped HZO layer is described.

[0149] Depending on the requirements of a particular MIM CAPS 300, different dopants may be used to create either an insulator or a doped HZO layer 314, thereby creating a MIM CAPS with specific design specifications.

[0150] In a particular embodiment, the method disclosed herein also includes a step of providing a seed layer before forming the doped HZO layer, and the seed layer is preferably a ZrO2 seed layer. The seed layer is used as a base or nucleation site for the subsequent deposition of the doped HZO layer. This seed layer creates a more favorable surface for the nucleation and growth of the doped HZO layer and provides a site for the HZO precursor molecules to attach and react. This will lead to a more uniform and controlled film growth. In addition, the seed layer can enhance the adhesion between the doped HZO layer and the substrate, thereby reducing the risk of delamination or peeling. In the case where the morphology or surface of the substrate makes conformal HZO deposition challenging, the seed layer will produce a smoother and more uniform surface, so that the subsequently deposited HZO layer has better conformal coverage. In some cases, the substrate material may react with the HZO precursor, resulting in an undesirable reaction or phase change. In these cases, the seed layer will act as a buffer layer to prevent direct contact between the substrate and the doped HZO precursor. It should be understood that when the seed layer is deposited on the substrate, the constituent components of these layers may be mixed to a certain extent.

[0151] For example, when a seed layer containing ZrO2 is deposited on a substrate, at least one of zirconium or oxygen can be incorporated into the substrate layer, such as by diffusion, surface separation, or another process. In some embodiments, this mixing can result in the formation of a sandwich containing both components of each layer.

[0152] In certain cases, such as when high dielectric constant values ​​above 35 between about -2 and -3 MV / cm are required, depositing a seed layer prior to doped HZO deposition can be beneficial in meeting these requirements and reducing the above-mentioned problems that may occur when such a seed layer is not used. Figure 4 An exemplary MIM CAPS 400 is shown having such a seed layer 413 and a doped HZO layer 414, rather than having only a doped HZO layer 414 as shown in FIG. Figure 3Doped HZO layer 314 is shown. In an exemplary embodiment, ZrO2 is used as a seed layer prior to doped HZO deposition. The seed layer helps promote the tetragonal phase and induces strain in the HZO film, thereby increasing the κ value. This, combined with the precise selection of dopants, helps obtain high κ values ​​in a specific voltage range, such as between -2 and -3 MV / cm. This combination can increase the κ value by 6 to 10%.

[0153] When even higher κ values ​​are required within a specific voltage range, a high κ dielectric layer can be provided in series with a high κ ferroelectric layer, and the combination of these layers can produce a maximum dielectric constant within the desired voltage range. Suitable high κ materials are, for example, SrTiO3, TiO2 or Nb2O5. These individual high κ layers can be problematic, for example, SrTiO3 loses its high dielectric constant when scaling below 9nm, and TiO2 is very leaky as deposited and after annealing, while Nb2O5 has been shown to not be very leaky as deposited, but it can become leaky after annealing. However, integrating them with a robust system such as a HZO layer doped with Si can increase the dielectric constant of the entire system while keeping leakage at an acceptable level.

[0154] While this may be a preferred solution in some cases, scalability when creating complex stacks may be compromised as each layer adds to the total thickness of the stack. In situations where maximum total thickness of the stack is required, it is recommended to convert a thin layer of the bottom metal to a suitable high-κ value material, such as converting the TiN to TiO2 or TiON by exposing the top layer of the TiN layer to O3. Instead of depositing Xnm of TiO2, the thin layer of the bottom TiN is converted to the intended TiO2 layer. This therefore results in a very thin and uniform bottom TiO2 layer.

[0155] Figure 5 Such an exemplary MIM CAPS 500 is shown having a top of a bottom TiN layer 512 deposited on a substrate 510, which is converted to a thin TiO2 layer 513 by exposing it to O3. In addition, a HZO layer 514 doped with Si is then deposited by ALD using metal organic precursors, followed by a Nb2O5 layer 515 deposited by ALD. Finally, a top TiN layer 516 is deposited by ALD, resulting in a MIM CAPS 500 with a reduced thickness compared to other stacked layer configurations.

[0156] Typically, the doped HZO layer is formed on a substrate that is first introduced into a reaction chamber before the doped HZO layer is formed. Non-limiting examples of substrates may include thin sheets or flexible materials. The substrate may also include a carrier or sheet on which the substrate is mounted.

[0157] In certain embodiments, the methods disclosed herein provide for forming a doped HZO layer or a layered doped HZO structure without any intermediate vacuum interruptions. Intermediate vacuum interruptions can cause process pauses, which is undesirable in high throughput manufacturing situations, resulting in a more continuous and smoother process. Additionally, deposition techniques such as ALD thrive on continuous and controlled precursor exposure. Interrupting the process with a vacuum interruption may introduce variations in film growth and quality, and may also increase contamination risk, as intermediate vacuum interruptions may introduce contaminants or oxygen, especially if the vacuum chamber is not thoroughly purged during the interruption. Thus, continuous deposition without introducing intermediate vacuum interruptions reduces the risk of introducing impurities in the doped HZO layer.

[0158] In some preferred embodiments, the present disclosure relates to a system, wherein the system is configured to perform the methods disclosed herein. Figure 6 Such a system 600 is shown according to an exemplary embodiment of the present disclosure. In the example shown, the system 600 can be used to perform the methods described herein and / or form part of the structures or devices described herein.

[0159] In the example shown, system 600 includes one or more reaction chambers 602, hafnium precursor source 603, zirconium precursor source 604, oxygen reactant source 605, dopant precursor source 606, purge gas source 608, exhaust 610, and controller 612. Reaction chamber 602 may include any suitable reaction chamber, such as an ALD reaction chamber.

[0160] Precursor sources 603, 604 may include containers and one or more precursors as described herein - alone or mixed with one or more carrier gases (e.g., inert gases). Dopant precursor source 606 may include a container and one or more dopant compounds as described herein - alone or mixed with one or more carrier gases. Purge gas source 608 may include one or more inert gases, such as N2 or a rare gas, as described herein. System 600 may include any suitable number of sources. Sources 603-608 may be coupled to reaction chamber 602 via lines 614-618, which may each include a flow controller, a valve, a heater, etc. Exhaust 610 may include one or more vacuum pumps.

[0161] The controller 612 includes electronic circuits and software to selectively operate valves, manifolds, heaters, pumps and other components included in the system 600. Such circuits and components are used to introduce precursors, reactants and purge gases from corresponding sources 604-608. The controller 612 can control the timing of gas pulse sequences, the temperature of the substrate and / or reaction chamber, the pressure in the reaction chamber, and various other operations to provide the correct operation of the system 600. The controller 612 may include control software to control the flow of precursors, reactants (i.e., nitrogen compounds and / or oxygen compounds) and purge gases into and out of the reaction chamber 602 by electrically or pneumatically controlling valves. The controller 612 may include modules that perform certain tasks, such as software or hardware components, such as FPGAs or ASICs. The modules may be advantageously configured to reside on an addressable storage medium of the control system and configured to perform one or more processes.

[0162] Other configurations of the system 600 are possible, including different numbers and types of precursor and reactant sources and purge gas sources. In addition, it should be understood that there are many arrangements of valves, conduits, precursor sources, and purge gas sources that can be used to achieve the goal of selectively supplying precursors, reactants, and / or gases to the reaction chamber 602. In addition, as a schematic representation of the system, many components have been omitted for simplicity of illustration, and these components may include, for example, various valves, manifolds, purifiers, heaters, containers, vents, and / or bypasses.

[0163] During operation of reactor system 600, a substrate, such as a semiconductor wafer (not shown), is transferred from, for example, a substrate handling system to reaction chamber 602. Once the substrate is transferred to reaction chamber 602, one or more gases, such as precursors, reactants, carrier gases, and / or purge gases, from gas sources 603-608 are introduced into reaction chamber 602.

[0164] It should be understood that the following examples can be applied to any of the methods disclosed herein, regardless of the precursors and / or reactants used in those methods, unless the corresponding examples would render the method in question unfeasible.

[0165] In some embodiments, the HZO layer is deposited at a temperature of at least 100°C to at most 500°C, or at least 150°C to at most 450°C, or at least 250°C to at most 350°C, or at about 350°C.

[0166] In some embodiments, the precursor is provided to the reaction chamber from a precursor source maintained at a temperature of at least 25°C to at most 200°C, or at least 50°C to at most 150°C, or at least 75°C to at most 125°C.

[0167] In some embodiments, the dopant compound is provided to the reaction chamber from a dopant source maintained at a temperature of at least 25°C to at most 200°C, or at least 50°C to at most 150°C, or at least 75°C to at most 125°C.

[0168] In some embodiments, the oxygen compound is provided to the reaction chamber from an oxygen source maintained at a temperature of at least 25°C to at most 200°C, or at least 50°C to at most 150°C, or at least 75°C to at most 125°C.

[0169] In some embodiments, the doped HZO layer is deposited at a pressure of at least 0.01 Torr to at most 100 Torr, or at least 0.1 Torr to at most 50 Torr, or at least 0.5 Torr to at most 25 Torr, or at least 1 Torr to at most 10 Torr, or at least 2 Torr to at most 5 Torr.

[0170] The doped HZO layer can be deposited in any suitable reactor. Thus, in some embodiments, the doped HZO layer is deposited in a cross-flow reactor. In some embodiments, the doped HZO layer is deposited in a showerhead reactor. In some embodiments, the doped HZO layer is deposited in a hot wall reactor. Doing so can advantageously improve the uniformity and / or repeatability of the doped HZO layer deposition process.

[0171] In some embodiments, after the cyclic deposition process, the substrate is subjected to an annealing step in an environment containing hydrogen and nitrogen. Suitably, the annealing step may be performed at a temperature of at least 300° C. to at most 600° C. Alternatively, the annealing step may be performed at a temperature of at least 300° C. to at most 1000° C.

[0172] In some embodiments, the precursor is provided to the reaction chamber from a temperature controlled precursor container. In some embodiments, the temperature controlled precursor container is configured to cool the precursor. In some embodiments, the temperature controlled precursor container is configured to heat the precursor. In some embodiments, the temperature controlled precursor container is maintained at a temperature of at least -50°C to at most 20°C, or at a temperature of at least 20°C to at most 250°C, or at least 100°C to at most 200°C.

[0173] In some embodiments, the precursor is provided to the reaction chamber by a carrier gas. Exemplary carrier gases include nitrogen (N2) and noble gases such as He, Ne, Ar, Xe or Kr.

[0174] As an exemplary embodiment, the method disclosed herein uses the method described herein according to Figure 6According to this embodiment, the precursor pulse includes hafnium and zirconium, and the dopant precursor pulse includes Si, Al or Ge. The following exemplary parameters are used during the material deposition in system 600:

[0175] - Substrate temperature: 160°C

[0176] -Pressure in reaction chamber: 8 Torr

[0177] - Precursor pulse (Hf and Zr): 100-150ms

[0178] -Purge time after precursor pulse: 40000ms

[0179] -Dopant pulse (Si, Al or Ge): 10000ms

[0180] -Purge time after dopant pulse: 40000ms

[0181] -Number of cycles: 400

[0182] The subject matter of the present disclosure includes all novel and nonobvious combinations and subcombinations of the various processes, systems and configurations, and other features, functions, acts, and / or properties disclosed herein, as well as any and all equivalents thereof.

[0183] The illustrations presented herein are not meant to be actual views of any particular material, structure, or device but are merely idealized representations used to describe embodiments of the present disclosure.

[0184] The specific embodiments shown and described are illustrative of the present disclosure and its best mode and are not intended to limit the scope of these aspects and embodiments in any way. In fact, for the sake of brevity, the traditional manufacturing, connection, preparation and other functional aspects of the system may not be described in detail. In addition, the connecting lines shown in the various figures are intended to represent exemplary functional relationships and / or physical connections between various elements. In actual systems, there may be many alternative or additional functional relationships or physical connections, and / or may not exist in some embodiments.

[0185] 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.

Claims

1. A method for forming a doped hafnium zirconium oxide (HZO) layer on a substrate, the method comprising the following steps: a) providing the substrate in a reaction chamber; b) executing one or more loops, the loops comprising: i. a hafnium precursor pulse, wherein at least a portion of the substrate is contacted with one or more hafnium precursors by introducing the one or more hafnium precursors into the reaction chamber; ii. a zirconium precursor pulse, wherein at least a portion of the substrate is contacted with one or more zirconium precursors by introducing the one or more zirconium precursors into the reaction chamber; iii. an oxygen reactant pulse, wherein at least a portion of the substrate is contacted with one or more oxygen reactants by introducing the one or more oxygen reactants into the reaction chamber; and iv. a dopant precursor pulse, wherein at least a portion of the substrate is contacted with one or more dopant precursors by introducing the one or more dopant precursors into the reaction chamber, Thereby forming a doped HZO layer; The dopant precursor includes a dopant element characterized by having three or four valence electrons and an atomic radius smaller than the atomic radius of the Hf or Zr element of the HZO layer.

2. The method according to claim 1, wherein: An oxygen reactant pulse is performed after each hafnium precursor pulse and / or after each zirconium precursor pulse.

3. The method according to claim 2, wherein: The dopant precursor pulse is performed after the hafnium precursor pulse without any intermediate oxygen reactant pulse.

4. The method according to claim 2, wherein: The dopant precursor pulse is performed after the zirconium precursor pulse without any intermediate oxygen reactant pulse.

5. The method according to claim 1, wherein: Each pulse is followed by a purge with an inert gas selected from at least one of N2 and a rare gas.

6. The method according to claim 1, wherein: The hafnium precursor pulse, the zirconium precursor pulse, the oxygen reactant pulse, and / or the dopant precursor pulse include a plurality of micropulses.

7. The method according to claim 1, wherein: The dopant element is selected from the group consisting of aluminum, silicon, nickel, germanium, gallium and carbon.

8. The method according to claim 1, wherein: The concentration of the dopant element in the HZO layer ranges between 0.50% and 8.0% relative dopant element concentration, more particularly between 1.0% and 5.0% relative dopant element concentration, and even more particularly between 2.0% and 4.50% relative dopant element concentration.

9. The method according to claim 1, wherein: The dopant element is Al.

10. The method according to claim 9, wherein: The dopant precursor is a low-reactivity precursor, and the dopant precursor is preferably composed of the general formula Al(R 1 )3 represents a low-reactivity aluminum precursor, wherein each R 1 are independently selected from hydrogen, halogen, alkyl, alkenyl, N(R 2 )2, cycloalkyl and alkoxy, and each R 2 is selected from hydrogen, alkyl or alkenyl.

11. The method according to claim 1, wherein: The dopant element is Si.

12. The method according to claim 11, wherein: The dopant precursor is a low-reactivity precursor, and the dopant precursor is preferably selected from silicon tetraacetate (Si(OOCCH3)4) and Si(R 3 )4, wherein each R 3 are independently selected from hydrogen, halogen, alkyl, alkenyl, N(R 4 )2, cycloalkyl and alkoxy, and each R 4 is selected from hydrogen, alkyl or alkenyl.

13. The method according to claim 1, wherein: The dopant element is Ge.

14. The method according to claim 13, wherein: The dopant precursor is a low-reactivity precursor, and the dopant precursor is preferably composed of the general formula Ge(R 5 )4 represented by a low-reactivity germanium precursor, wherein each R 5 are independently selected from hydrogen, halogen, alkyl, alkenyl, N(R 6 )2, cycloalkyl and alkoxy, and each R 6 is selected from hydrogen, alkyl or alkenyl.

15. The method according to claim 1, wherein: The hafnium precursor is selected from HfCl4, HfBr4, HfI4, tetrakis(dimethylamino)hafnium (Hf(N(CH3)2)4), tetrakis(ethylmethylamino)hafnium (Hf(N(C2H5)(CH3))4), tetrakis(diethylamino)hafnium (Hf(N(C2H5)2)4), Hf(OR)4, tris(dimethylamino)cyclopentadienylhafnium (HfCp(NMe2)3), Hf(CpMe)2[OMe]Me, Hf(CpMe)2Me2 and tetrakis(1-methoxy-2-methyl-2-propoxy)hafnium (Hf(mmp)4).

16. The method according to claim 1, wherein: The zirconium precursor is selected from the group consisting of tetrakis(dimethylamino)zirconium, tetrakis(diethylamino)zirconium, tetrakis(ethylmethylamino)zirconium and tris(dimethylamino)cyclopentadienylzirconium.

17. The method according to claim 1, wherein: The dopant precursor has a decomposition temperature higher than the operating temperature of forming the doped hafnium zirconium oxide (HZO) layer.

18. The method according to claim 17, wherein: The operating temperature for forming the doped HZO layer is between 150°C and 450°C, preferably between 250°C and 350°C, and more preferably about 300°C.

19. The method according to claim 1, wherein: The method is an atomic layer deposition (ALD) method.

20. The method according to claim 1, wherein: The method further comprises the step of providing a seed layer before forming the doped HZO layer, the seed layer being a ZrO 2 seed layer.

21. The method according to claim 1, wherein: The substrate comprises a metal oxide (MO) surface layer, and / or wherein, The method further includes the step of forming a metal oxide (MO) top layer on the doped HZO layer, thereby forming a layered doped HZO structure.

22. The method according to claim 21, wherein: The MO surface layer and / or the MO top layer are in direct contact with the doped HZO layer.

23. The method according to claim 21, wherein: The metal oxide is TiO2.

24. The method according to claim 1, wherein: The doped HZO layer stabilizes the tetragonal phase of the HZO layer so that a morphotropic phase boundary (MPB) is reached between the orthorhombic phase and the tetragonal phase of the HZO layer to allow a polarization switching voltage of the HZO layer to be changed.

25. The method according to claim 24, wherein: Changing the polarization switching voltage of the HZO layer changes the capacitance-voltage (CV) linearity of the HZO layer.

26. The method of claim 1, wherein: The doped HZO layer increases the dielectric constant value (κ) of the HZO layer.

27. The method according to claim 26, wherein: The dielectric constant value (κ) of the doped HZO layer is greater than 35 at about -2 and -3 MV / cm.

28. The method of claim 1, wherein: The doped HZO layer is formed without any intermediate vacuum break.

29. The method according to claim 21, wherein: The layered doped HZO structure is formed without any intermediate vacuum interruption.

30. A doped hafnium zirconium oxide (HZO) layer obtained by the method according to claim 1.

31. A layered doped HZO structure obtained by the method according to claim 21.

32. Use of a doped hafnium zirconium oxide (HZO) layer obtained by the method according to claim 1 as an insulator in a metal-insulator-metal capacitor (MIM CAPS).

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