WO2009155520A1

WO2009155520A1 - Hafnium and zirconium pyrrolyl-based organometallic precursors and use thereof for preparing dielectric thin films

Info

Publication number: WO2009155520A1
Application number: PCT/US2009/047957
Authority: WO
Inventors: Peter Nicholas Heys; Rajesh Odedra; Andrew Kingsley; Hywel Owen Davies
Original assignee: Sigma-Aldrich Co.
Priority date: 2008-06-20
Filing date: 2009-06-19
Publication date: 2009-12-23
Also published as: TW201014924A; WO2009155507A1; TW201014925A

Abstract

Hafnium and zirconium pyrrolyl-based organometallic precursors and methods of use thereof are provided to prepare metal-containing dielectric thin films by a vapor deposition process. The organometallic precursors correspond in structure to Formula I or dimers of Formula I: [(R)_nPy]M(L)₃ (Formula I) wherein: R is independently selected from the group consisting of alkyl, alkoxy and NR¹R²; R¹ and R² are each independently hydrogen or alkyl; n is zero, 1, 2, 3 or 4; Py is pyrrolyl; M is Hf or Zr; L is selected from the group consisting of alkyl, alkoxy and NR¹R².

Description

HAFNIUM AND ZIRCONIUM PYRROLYL-BASED ORGANOMETALLIC PRECURSORS AND USE THEREOF FOR PREPARING DIELECTRIC THIN

FILMS

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This patent claims the benefit of U.S. provisional application Serial No. 61/074,363, filed on 20 June 2008, U.S. provisional application Serial No. 61/177,137, filed on 11 May 2009 and U.S. provisional application Serial No. 61/177,165, filed on 11 May 2009. The disclosure of each recited U.S. provisional application is incorporated by reference in its entirety.

FIELD OF THE INVENTION

[0002] The present invention relates to pyrrolyl-based organometallic precursors and methods of preparing dielectric thin films by chemical vapor deposition (CVD) and atomic layer deposition (ALD) using such precursors.

BACKGROUND OF THE INVENTION

[0003] Various organometallic precursors are used to form high-κ dielectric thin metal films. A variety of techniques have been used for the deposition of thin films. These include reactive sputtering, ion-assisted deposition, sol-gel deposition, CVD, and ALD, also known at atomic layer epitaxy. The CVD and ALD processes are being increasingly used as they have the advantages of good composition control, high film uniformity, good control of doping and, significantly, they give excellent conformal step coverage on highly non-planar microelectronics device geometries. [0004] CVD (also referred to as metalorganic CVD or MOCVD) is a chemical process whereby precursors are deposited on a substrate to form a solid thin film. In a typical CVD process, the precursors are passed over a substrate (wafer) within a low pressure or ambient pressure reaction chamber. The precursors react and/or decompose on the substrate surface creating a thin film of deposited material. Volatile by-products are removed by gas flow through the reaction chamber. The deposited film thickness can be difficult to control because it depends on coordination of many parameters such as temperature, pressure, gas flow volumes and uniformity, chemical depletion effects and time. [0005] ALD is another method for the deposition of thin films. It is a self -limiting, sequential, unique film growth technique based on surface reactions that can provide atomic layer-forming control and deposit-conformal thin films of materials provided by precursors onto substrates of varying compositions. In ALD, the precursors are separated during the reaction. The first precursor is passed over the substrate producing a monolayer on the substrate. Any excess unreacted precursor is pumped out of the reaction chamber. A second precursor is then passed over the substrate and reacts with the first precursor, forming a second monolayer of film over the first-formed film on the substrate surface. This cycle is repeated to create a film of desired thickness. ALD film growth is self-limited and based on surface reactions, creating uniform depositions that can be controlled at the nanometer- thickness scale.

[0006] Dielectric thin films have a variety of important applications, such as nanotechnology and fabrication of semiconductor devices. Examples of such applications include high-refractive index optical coatings, corrosion-protection coatings, photocatalytic self-cleaning glass coatings, biocompatible coatings, dielectric capacitor layers and gate dielectric insulating films in FETS, capacitor electrodes, gate electrodes, adhesive diffusion barriers and integrated circuits. Dielectric thin films are also used in microelectronics applications, such as the high-*; dielectric oxide for dynamic random access memory (DRAM) applications and the ferroelectric perovskites used in infra-red detectors and non-volatile ferroelectric random access memories (NV-FeRAMs). The continual decrease in the size of microelectronics components has increased the need for the use of such dielectric thin films.

[0007] Tanski J. and Parkin G. report a series of structurally characterized zirconium- pyrrolyl complexes. Organometallics , 21:587-589, (2002).

[0008] Choukroun et al. report reactivity of the titanium-nitrogen bond in the mixed trisalkoxy dialkylamide derivative Ti(OR)₃(NEt₂). Synth. React. Inorg. Met.-Org. Chem. 8(2):137-147, (1978).

[0009] Dias et al. report the synthesis and characterization of the complex [Ti(NC₄Me₄)(NMe₂)S] Collect. Czech. Chem. Commun. 63:182-186, (1998). [0010] Dias et al. report synthesis and characterization of titanium complexes containing 2,3,4,5-tetramethylpyrrolyl. J. Chem. Soc, Dalton Trans. 1055-1061, (1997). [0011] Bradley D. and Chivers K. report metallo-organic compounds such as Ti(NC₄H₂Me₂)(NEt₂)S. Inorg. Phys. Theor. 1967-1969, (1968).

[0012] Current precursors for use in CVD and ALD do not provide the required performance to implement new processes for fabrication of next generation devices, such as semi-conductors. For example, improved thermal stability, higher volatility, increased deposition rates and a high permittivity are needed.

SUMMARY OF THE INVENTION

[0013] In one embodiment a hafnium or zirconium organometallic precursor is provided. The precursor corresponds in structure to Formula I:

[(R)_nPy]M(L)₃

(Formula I) wherein:

R is independently selected from the group consisting of alkyl, alkoxy and NR¹R²; R¹ and R² are each independently hydrogen or alkyl; n is zero, 1, 2, 3 or 4; Py is pyrrolyl; M is Hf or Zr; and

L is selected from the group consisting of alkyl, alkoxy and NR¹R². [0014] In another embodiment, a method of forming a metal-containing film by a vapor deposition process is provided. The method comprises delivering at least one precursor to a substrate, wherein the at least one precursor corresponds in structure to Formula I above.

[0015] Other embodiments, including particular aspects of the embodiments summarized above, will be evident from the detailed description that follows.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Fig. 1 is a graphical representation of thermogravimetric analysis (TGA) data demonstrating % weight loss vs. temperature of ((te/t-butyl)₂Py)Zr(NMe₂)₃.

DETAILED DESCRIPTION OF THE INVENTION

[0017] In various aspects of the invention, pyrrolyl-based organometallic precursors and methods of using such precursors to form thin metal-containing films, such as metal oxide films or metal nitride films, are provided. [0018] The methods of the invention are used to create or grow metal-containing thin films which display high dielectric constants. A dielectric thin film as used herein refers to a thin film having a high permittivity.

A. Definitions

[0019] As used herein, the term "high-κ dielectric" refers to a material, such as a metal-containing film, with a higher dielectric constant (K) when compared to silicon dioxide (which has a dielectric constant of about 3.7). Typically, a high-κ dielectric film is used in semiconductor manufacturing processes to replace a silicon dioxide gate dielectric. A high-κ dielectric film may be referred to as having a "high-κ gate property" when the dielectric film is used as a gate material and has at least a higher dielectric constant than silicon dioxide.

[0020] As used herein, the term "relative permittivity" is synonymous with dielectric constant (K).

[0021] As used herein, the term "vapor deposition process" is used to refer to any type of vapor deposition technique such as CVD or ALD. In various embodiments of the invention, CVD may take the form of conventional CVD, liquid injection CVD or photo- assisted CVD. In other embodiments, ALD may take the form of conventional ALD, liquid injection ALD or photo-assisted ALD.

[0022] As used herein, the term "precursor" refers to an organometallic molecule, complex and/or compound which is deposited or delivered to a substrate to form a thin film by a vapor deposition process such as CVD or ALD.

[0023] In a particular embodiment, the precursor may be dissolved in an appropriate hydrocarbon or amine solvent. Appropriate hydrocarbon solvents include, but are not limited, to aliphatic hydrocarbons, such as hexane, heptane and nonane; aromatic hydrocarbons, such as toluene and xylene; aliphatic and cyclic ethers, such as diglyme, triglyme and tetraglyme. Examples of appropriate amine solvents include, without limitation, octylamine and N,N-dimethyldodecylamine. For example, the precursor may be dissolved in toluene to yield a 0.05 to IM solution.

[0024] As used herein, the term "Py" refers to a pyrrolyl ligand which is bound to a metal center. [0025] The term "alkyl" (alone or in combination with another term(s)) refers to a saturated hydrocarbon chain of 1 to about 10 carbon atoms in length, such as, but not limited to, methyl, ethyl, propyl and butyl. The alkyl group may be straight-chain or branched-chain. For example, as used herein, propyl encompasses both w-propyl and iso- propyl; butyl encompasses w-butyl, sec-butyl, iso-butyl and tert-butyl. Further, as used herein, "Me" refers to methyl, "Et" refers to ethyl, "iPr" refers to iso-propyl and "tBu" refers to tert-butyl.

[0026] The term "alkoxy" (alone or in combination with another term(s)) refers to a substituent, i.e., -O-alkyl. Examples of such a substituent include methoxy (-0-CH₃), ethoxy, etc. The alkyl portion may be straight-chain or branched-chain. For example, as used herein, propoxy encompasses both w-propoxy and iso-propoxy; butoxy encompasses w-butoxy, zso-butoxy, sec-butoxy, and tert-butoxy.

[0027] The term "amino" herein refers to an optionally substituted monovalent nitrogen atom (i.e., -NR¹R², where R¹ and R² can be the same or different). Examples of

amino groups encompassed by the invention include, but are not limited to, -I -N(Me)₂

4* -N(Et)₂ — <-N(Et)(Me) and s and *> . Further, the nitrogen atom of this amino group is covalently bonded to the metal center which together may be referred to as an "amide"

group (i.e.

This can be further referred to as an "ammono" group or

- I|-Hf— N /^R1 _ §|__Zr__N /' ^R1 inorganic amide, for example R² or R² wherein R¹ and R² are independently hydrogen or alkyl.

B. Organometallic Precursors

[0028] In a first embodiment, an organometallic precursor is provided. The organometallic precursor corresponds in structure to Formula I:

[(R)_nPy]M(L)₃

(Formula I) wherein: R is independently selected from the group consisting of alkyl, alkoxy and NR¹R²; R¹ and R² are each independently hydrogen or alkyl; n is zero, 1, 2, 3 or 4;

Py is pyrrolyl;

M is Hf or Zr;

L is selected from the group consisting of alkyl, alkoxy and NR¹R²

[0029] The metal center of the precursor according to Formula I is comprised of a

Group IVB metal, i.e. hafnium or zirconium.

[0030] In one embodiment, R is alkyl, such as methyl, ethyl, propyl, or butyl.

[0031] In another embodiment, R is alkoxy, such as methoxy, ethoxy, propoxy or butoxy.

[0032] In yet another embodiment, R is NR¹R², wherein R¹ and R² are each independently hydrogen or alkyl. For example, in one embodiment, R is N(Me)₂ or

NH(Me) or N(Et)₂ or NH(Et) or N(Me)(Et).

[0033] The variable n is the number of R groups substituted on the pyrrolyl ligand.

There may be from zero to four R groups substituted on the pyrrolyl ligand. If more than one R group is present, the R groups may be the same or different. In a particular embodiment, n is 1, 2, 3, or 4. In another embodiment, n is 2, 3 or 4. In another embodiment, n is 2 or 3. In a further particular embodiment, n is 2.

[0034] There are three L substituents bonded to the metal center. Each L substituent is the same. This can be referred to as a "piano stool" arrangement.

[0035] In one embodiment, L is alkyl, such as methyl, ethyl, propyl, or butyl.

[0036] In another embodiment, L is alkoxy, such as methoxy, ethoxy, propoxy or butoxy.

[0037] In yet another embodiment, L is NR¹R², wherein R¹ and R² are each independently hydrogen or alkyl. For example, in one embodiment, L is N(Me)₂ or

NH(Me) or N(Et)₂ or NH(Et) or N(Me)(Et).

[0038] In one embodiment, the at least one precursor corresponds in structure to

Formula I wherein:

R is independently alkyl or alkoxy;

R¹ and R² are each independently hydrogen or alkyl; n is 1, 2, 3 or 4; Py is pyrrolyl;

M is Hf or Zr; and

L is alkoxy or NR¹R²

[0039] In another embodiment, the at least one precursor corresponds in structure to

Formula I wherein:

M is Zr;

R is independently methyl, ethyl, propyl or butyl; n is zero, 1, 2, 3, or 4; and

L is methoxy, ethoxy, propoxy, butoxy, N(Me)₂ or N(Me)(Et).

[0040] In another embodiment, the at least one precursor corresponds in structure to

Formula I wherein:

M is Hf;

L is methoxy, ethoxy, propoxy, butoxy, N(Me)₂ or N(Me)(Et).

[0041] In another embodiment, the at least one precursor corresponds in structure to

Formula I wherein:

M is Zr;

R is independently methyl, ethyl, propyl or butyl; n is 1, 2, 3, or 4; and

L is methoxy, ethoxy, propoxy, butoxy, N(Me)₂ or N(Me)(Et).

[0042] In another embodiment, the at least one precursor corresponds in structure to

Formula I wherein:

M is Hf;

R is independently methyl, ethyl, propyl or butyl; n is 1, 2, 3, or 4; and

L is methoxy, ethoxy, propoxy, butoxy, N(Me)₂ or N(Me)(Et).

[0043] In a particular embodiment, the at least one precursor corresponding in structure to Formula I is:

(Py)Zr(NMe₂)₃;

(Me₂Py)Zr(NMe₂)₃; [(te/t-butyl)₂Py]Zr(NMe₂)₃ ; (Py)Hf(NMe₂)₃ ; (Me₂Py)Hf(NMe₂)₃ ; [(te/t-butyl)₂Py]Hf(NMe₂)₃; (Py)Zr(O¹Pr)₃; (Me₂Py)Zr(O¹Pr)₃; [(fert-butyl)₂Py]Zr(O¹Pr)₃; (Py)Hf(O¹Pr)₃; (Me₂Py)Hf(O¹Pr)₃; and [(tert-butylhPyWiO'Prh.

[0044] The precursors described above can all be referred to as monomers. However, it is possible that the monomers may also dimerize. Thus, in another embodiment dimers of the above disclosed monomers are also provided. These organometallic precursors correspond in structure to Formula II:

X:X

(Formula II) wherein: each X can be the same or different and corresponds in structure to [(R)_nPy]M(L)₃ wherein:

R is independently selected from the group consisting of alkyl, alkoxy and NR¹R²;

R¹ and R² are each independently hydrogen or alkyl; n is zero, 1, 2, 3 or 4;

Py is pyrrolyl;

M is Hf or Zr; and

L is selected from the group consisting of alkyl, alkoxy and NR¹R² [0045] Each of the embodiments recited above for Formula I precursors may be applied mutatis mutandis to the organometallic precursors of Formula II.

C. Methods of Use

[0046] In another embodiment a method of forming a metal-containing film by a vapor deposition process is provided. [0047] In one embodiment, the vapor deposition process is chemical vapor deposition.

[0048] In another embodiment, the vapor deposition process is atomic layer deposition.

[0049] The method comprises delivering at least one precursor to a substrate, wherein the at least one precursor corresponds in structure to Formula I and/or II above. [0050] The ALD and CVD methods of the invention encompass various types of ALD and CVD processes such as, but not limited to, conventional processes, liquid injection processes and photo-assisted processes.

[0051] In one embodiment, conventional CVD is used to form a metal-containing thin film using at least one precursor according to Formula I and/or II. For conventional CVD processes, see for example Smith, Donald (1995). Thin-Film Deposition: Principles and Practice. McGraw-Hill.

[0052] In another embodiment, liquid injection CVD is used to form a metal- containing thin film using at least one precursor according to Formula I and/or II. [0053] Examples of liquid injection CVD growth conditions include, but are not limited to:

(1) Substrate temperature: 200-600⁰C on Si(IOO)

(2) Evaporator temperature: about 200⁰C

(3) Reactor pressure: about 5mbar

(4) Solvent: toluene, or any solvent mentioned above

(5) Solution concentration: about 0.05 M

(6) Injection rate: about 30 cmV

(7) Argon flow rate: about 200 cm³ min ¹

(8) Oxygen flow rate: about 100 cm³ min^"1

(9) Run time: 10 min

[0054] In another embodiment, photo-assisted CVD is used to form a metal- containing thin film using at least one precursor according to Formula I and/or II. [0055] In a further embodiment, conventional ALD is used to form a metal- containing thin film using at least one precursor according to Formula I and/or II. For conventional and/or pulsed injection ALD process see, for example, George S. M., et. al. J. Phys. Chem. 1996. 100:13121-13131.

[0056] In another embodiment, liquid injection ALD is used to form a metal- containing thin film using at least one precursor according to Formula I and/or II, wherein at least one liquid precursor is delivered to the reaction chamber by direct liquid injection as opposed to vapor draw by a bubbler. For liquid injection ALD process see, for example, Potter R. J., et. al. Chem. Vap. Deposition. 2005. 11(3): 159. [0057] Examples of liquid injection ALD growth conditions include, but are not limited to:

(1) Substrate temperature: 160-300⁰C on Si(IOO)

(2) Evaporator temperature: about 175⁰C

(3) Reactor pressure: about 5mbar

(4) Solvent: toluene, or any solvent mentioned above

(5) Solution concentration: about 0.05 M

(6) Injection rate: about 2.5μl pulse^"1 (4 pulses cycle^"1)

(7) Inert gas flow rate: about 200 cm³ min^"1

(8) Pulse sequence (sec.) (precursor/purge/H₂O/purge): will vary according to chamber size.

(9) Number of cycles: will vary according to desired film thickness.

[0058] In another embodiment, photo-assisted ALD is used to form a metal- containing thin film using at least one precursor according to Formula I and/or II. For photo-assisted ALD processes see, for example, U.S. Patent No. 4,581,249. [0059] Thus, the organometallic precursors according to Formula I and/or II utilized in these methods may be liquid, solid, or gaseous. Particularly, the precursors are liquid at ambient temperatures with high vapor pressure allowing for consistent transport of the vapor to the process chamber.

[0060] In one embodiment, the precursors corresponding to Formula I and/or II are delivered to the substrate in pulses alternating with pulses of an oxygen source, such as a reactive oxygen species. Examples of such oxygen source include, without limitation, H₂O, O₂ and/or ozone.

D. Mixed Metal Films [0061] In another embodiment of the invention, the method further comprises delivering for deposition at least one co-precursor to form a "mixed" metal film. [0062] In a particular embodiment, the method further comprises delivering for deposition at least one co-precursor to form a mixed metal oxide film. As used herein, a mixed metal oxide film contains at least two different metals.

[0063] In one embodiment, two or more precursors corresponding in structure to Formula I and/or II may be used to form a mixed metal oxide film. For example, a hafnium and zirconium precursor can be used to create a hafnium-zirconium oxide film. [0064] In another embodiment, a hafnium or zirconium precursor corresponding in structure to Formula I and/or II may be used in CVD or ALD with at least one titanium, strontium, bismuth, barium or lanthanum precursor to form a mixed metal oxide film. Examples of such mixed metal oxide films formed include, without limitation, SrZrO₃, SrHfO₃, LaZrO₃ and LaHfO₃.

E. Co-Reactants

[0065] A dielectric film can also be formed by the at least one precursor corresponding to Formula I and/or II, independently or in combination with a co-reactant. Examples of such co-reactants include, but are not limited to, hydrogen, hydrogen plasma, oxygen, air, water, H₂O₂, ammonia, hydrazine, alkylhydrazine, borane, silane, ozone or any combination thereof.

F. Substrates

[0066] A variety of substrates can be used in the methods of the present invention. For example, the precursors according to Formula I and/or II may be delivered for deposition on substrates such as, but not limited to, silicon, silicon oxide, silicon nitride, tantalum, tantalum nitride, copper, ruthenium, titanium nitride, tungsten, and tungsten nitride.

G. Applications

[0067] In particular embodiments, the method of the invention is utilized for applications such as dynamic random access memory (DRAM) and complementary metal oxide semi-conductor (CMOS) for memory and logic applications on silicon chips. [0068] Fundamental differences exist between the thermally-driven CVD process and the reactivity-driven ALD process. The requirements for precursor properties to achieve optimum performance vary greatly. In CVD a clean thermal decomposition of the precursor to deposit the required species onto the substrate is critical. However, in ALD such a thermal decomposition is to be avoided at all costs. In ALD the reaction between the input reagents must be rapid and result in the target material formation on the substrate. However, in CVD any such reaction between species is detrimental due to their gas phase mixing before reaching the substrate to generate particles. In general, a good CVD source will be a poor ALD source and vice versa and therefore it is surprising that the pyrrolyl-based molecules of this invention perform well in both ALD and CVD processes.

[0069] The pyrrolyl-based precursors offer access to different temperature windows for deposition processes when compared to conventional precursors. This makes matching of these pyrrolyl-based precursors with other metal sources open to more manipulation when attempting to deposit ternary or quaternary alloys in an optimized fashion.

EXAMPLES

[0070] The following examples are merely illustrative, and do not limit this disclosure in any way.

[0071] All manipulations are carried out under an atmosphere of dry nitrogen using standard Schlenk line or dry box techniques. Dry solvents and other starting materials are supplied by Sigma- Aldrich Ltd. and are purified where necessary.

[0072] Auger electron spectroscopy (AES) is carried out on a Varian scanning Auger spectrometer. The atomic compositions are quoted from the bulk of the film (typically 70 - 80 nm depth), free from surface contamination, and are obtained by combining AES with sequential argon ion bombardment until comparable compositions are obtained for consecutive data points. Compositions are based on a HfO₂ or ZrO₂ powder reference.

[0073] Example 1 - Preparation of [tort-butyl)?pyrrolyllZr[N(CHO?^

[0074] To a solution of Zr(N(CH₃)₂)₄ (1.5g, 0.0056 moles) in toluene (20ml) was added via canula a solution of (te/t-butyl)₂(pyrrole) (l.Og, 0.0056 moles) in toluene

(20 mis) at room temperature. The solution was heated to 7O⁰C for 3 hours and the solvent removed leaving [(fert-butyl)₂pyrrolyl]Zr[N(CH₃)2]3 as a low melting

(~30°C) white solid. ¹H NMR spectroscopy was carried out on a Bruker Avance 400

NMR spectrometer (¹H 400.1 MHz). NMR: 1.3 ppm (t-butyl), 3.1 ppm (NMe2)3, and

6.1 ppm (pyrrolyl).

[0075] Figure 1 represents TGA data for [(te/t-butyl)₂pyrrolyl]Zr[N(CH₃)₂]₃.

Thermogravimetic Analysis (TGA) was carried out on a Mettler Toledo thermogravimetric analyzer in a nitrogen filled glove box.

[0076] Example 2 - CVD and ALD studies

[0077] Liquid injection CVD and ALD experiments are carried out on an Aixtron

AIX 200FE AVD reactor fitted with a modified liquid injection system. During the CVD experiments, oxygen is introduced at the inlet of the reactor. For the ALD experiments, the oxygen is replaced by ozone, which is controlled by a pneumatic valve. The substrate is rotated throughout the CVD experiments. Films of ZrO₂ or HfO₂ are deposited on Si

(100) substrates using 0.05M solutions of precursor in toluene.

[0078] Exemplary CVD and ALD growth conditions which may be effective for deposition are shown in Table 1.

Table 1. Possible growth conditions for the deposition of ZrO₂ films by liquid injection CVD and ALD using [tert-butyl)?pyrrolyllZr[N(CHO?^

Pulse sequence (sec.) [Zr precursor]/purge/water/purge/— 2 / 2/ 0.5 / 3.5

[0079] All patents and publications cited herein are incorporated by reference into this application in their entirety.

[0080] The words "comprise", "comprises", and "comprising" are to be interpreted inclusively rather than exclusively.

Claims

WHAT IS CLAIMED IS:

1. A method of forming a metal-containing film by a vapor deposition process, the method comprising delivering at least one precursor to a substrate, wherein the at least one precursor corresponds in structure to Formula I:

[(R)_nPy]M(L)₃

(Formula I) wherein:

R is independently selected from the group consisting of alkyl, alkoxy and NR¹R²; R¹ and R² are each independently hydrogen or alkyl; n is zero, 1, 2, 3 or 4; Py is pyrrolyl; M is Hf or Zr; and L is selected from the group consisting of alkyl, alkoxy and NR¹R²

2. The method of Claim 1, wherein R is independently alkyl or alkoxy;

R¹ and R² are each independently hydrogen or alkyl; n is 1, 2, 3 or 4; Py is pyrrolyl; M is Hf or Zr; and L is alkoxy or NR¹R²

3. The method of Claim 1, wherein M is Zr;

L is methoxy, ethoxy, propoxy, butoxy, N(Me)₂ or N(Me)(Et).

4. The method of Claim 1, wherein M is Hf;

L is methoxy, ethoxy, propoxy, butoxy, N(Me)₂ or N(Me)(Et).

5. The method of Claim 1, wherein M is Zr;

R is independently methyl, ethyl, propyl or butyl; n is 1, 2, 3, or 4; and

L is methoxy, ethoxy, propoxy, butoxy, N(Me)₂ or N(Me)(Et).

6. The method of Claim 1, wherein M is Hf;

R is independently methyl, ethyl, propyl or butyl; n is 1, 2, 3, or 4; and

L is methoxy, ethoxy, propoxy, butoxy, N(Me)₂ or N(Me)(Et).

7. The method of Claim 1, wherein the at least one precursor is selected from the group consisting of:

(Py)Zr(NMe₂)₃; (Me₂Py)Zr(NMe₂)₃; [(tert-butyl)₂Py]Zr(NMe₂)₃; (Py)Hf(NMe₂)₃; (Me₂Py)Hf(NMe₂)₃ ; [(tert-butyl)₂Py]Hf(NMe₂)₃; (Py)Zr(O¹Pr)₃; (Me₂Py)Zr(O¹Pr)₃; [(fer?-butyl)₂Py]Zr(O¹Pr)₃ ; (Py)Hf(O¹Pr)₃; (Me₂Py)Hf(O¹Pr)₃; and [(tert-butyl^yJHfCO'Prk.

8. The method of Claim 1, wherein the vapor deposition process is chemical vapor deposition.

9. The method of Claim 8, wherein the chemical vapor deposition is liquid injection chemical vapor deposition.

10. The method of Claim 1, wherein the vapor deposition process is atomic layer deposition.

11. The method of Claim 10, wherein the atomic layer deposition is liquid injection atomic layer deposition.

12. The method of Claim 10, wherein the atomic layer deposition is pulsed injection atomic layer deposition.

13. The method of Claim 1, wherein the at least one precursor is delivered to the substrate in pulses alternating with pulses of an oxygen source to form a metal oxide film.

14. The method of Claim 13, wherein the oxygen source is selected from H₂O, O₂ or ozone.

15. The method of Claim 13, further comprising delivering at least one co-precursor to form a mixed metal oxide film.

16. The method of Claim 15, wherein the mixed metal oxide film is selected from the group consisting of SrTiO₃, SrZrO₃, SrHfO₃, LaTiO₃, LaZrO₃, LaHfO₃, BaTiO₃ and BiTiO₃.

17. The method of Claim 1, further comprising delivering at least one appropriate co- reactant selected from the group consisting of hydrogen, hydrogen plasma, oxygen, air, water, ammonia, hydrazine, alkylhydrazine, borane, silane, ozone and a combination thereof.

18. The method of Claim 1, wherein the substrate is selected from the group consisting of silicon, silicon oxide, silicon nitride, tantalum, tantalum nitride, copper, ruthenium, titanium nitride, tungsten, and tungsten nitride.

19. The method of Claim 1, wherein the method is used for a memory or logic application.

20. The method of Claim 19, wherein the method is used for a DRAM or CMOS application.

21. An organometallic precursor corresponding in structure to Formula I:

[(R)_nPy]M(L)₃

(Formula I) wherein:

R is independently selected from the group consisting of alkyl, alkoxy and NR¹R²; R¹ and R² are each independently hydrogen or alkyl; n is zero, 1, 2, 3 or 4; Py is pyrrolyl; M is Hf or Zr; and L is selected from the group consisting of alkyl, alkoxy and NR¹R².