Synthesis of WN(NMe2)3 as a Precursor for the Deposition of WNx Nanospheres

McClain, K. Randall; O’Donohue, Christopher; Shi, Zhiwei; Walker, Amy V.; Abboud, Khalil A.; Anderson, Tim; McElwee‐White, Lisa

doi:10.1002/ejic.201200254

Cited by 24 publications

(37 citation statements)

References 63 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Synthesis of complexes 3-6. was recorded as 1.718 (6) and is similar to those of the reported mono imido complexes of tungsten such as, WCl 4 (NC 6 H 4 Me-p)(thf) (1.711 (7) ) and Cl 4 (CH 3 CN)W(NC 3 H 5 ) (1.687 (9) ) where these bonds are suggested to be having partial triple bond character. For comparison, the above bond lengths are shorter than the W=N bond lengths in WCl 2 (N t Bu) 2 (py) 2 [1.761 (4) & 1.746(4) ], [29] WCl 2 (N t Bu) 2 (bipy) [1.747(5) & 1.754(4) ], [34] and WCl 2 (N t Bu) 2 ( t Bu-dab) [1.756(8) & 1.758 (8) ], but longer than the W N bond lengths in nitride complexes such as, WN(NMe 2 ) 3 [1.680(2) ], [33] WN[OC(CF 3 ) 2 (CH 3 )] 3 ·DME [1.680 (5) ], [38] and WN[N(Ar) i Pr] 3 [1.669(5) ] (Ar = 3,5-C 6 H 3 Me 2 ) [39] reiterating the intermediate nature of bond between tungsten and the imido nitrogen atom in 1. Because of the strong bonding between the tungsten and imido nitrogen atom in 1, the tungsten atom appears to be displaced out of the plane of the four chlorine atoms towards the imido nitrogen atom.…”

Section: Crystal Structure Ofmentioning

confidence: 99%

“…Previous studies demonstrate the relation between C–N bond strengths and WN x /WN x C y deposition, where the imido C–N bond dissociation is the rate determining step . However, the designed precursors making use of the above observations were not able to produce the desired results . Therefore, we decided to continue the design of the imido tungsten precursors by limiting the number of the imido ligands to one and substituting the remaining tungsten valences with amido ligands.…”

Section: Introductionmentioning

confidence: 99%

“…This requires development of new precursors of metal-organic nature and mild reaction by-products. As a result, several tungsten complexes of nitrogen-bound ligands (including amide, [17,18,33] imide, [18][19][20][21][22][23][24][25] hydrazido, [26,27] amidinate, [20] and guanidinate [28][29][30] ligands) as single-source precursors were developed. [31] These precursors afforded halogenand oxygen-free tungsten nitride or tungsten carbonitride films when used in the ALD/CVD process in the presence of appropriate reductive gases (H 2 or NH 3 ).…”

Section: Introductionmentioning

confidence: 99%

“…[20,2,32] However, the designed precursors making use of the above observations were not able to produce the desired results. [26,33] Therefore, we decided to continue the design of the imido tungsten precursors by limiting the number of the imido ligands to one and substituting the remaining tungsten valences with amido ligands. This demonstrates easy dissociation characteristics.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Synthesis of Mono‐Imido Tungsten Complexes Directly from WCl₆

et al. 2016

View full text Add to dashboard Cite

A new series of tungsten complexes were prepared using WCl6, N‐tert‐butyltrimethylsilylamine, and amide ligands as potential precursors for WNx thin film deposition. The complexes [W(NtBu)(NMe2)4] (2), [W(NtBu)(MeNCH2CH2NMe)2] (3), [W(NtBu)(MeNCH2CH2CH2NMe)2] (4), [W(NtBu)(iPrNCH2CH2NiPr)2] (5), and [W(NtBu)(tBuNCH2CH2NtBu)2] (6) were prepared by a two‐step process. First, the controlled reaction between WCl6 and N‐tert‐butyltrimethylsilylamine afforded the complex [W(NtBu)Cl4(py)] (1) from which the substitution of chloride ions with the corresponding amide ligands gave complexes 2–6. Single crystal X‐ray crystallography showed that complex 1 crystalized in the triclinic space group P‐1 with an octahedral structure. Among complexes 2–6, complexes 4 and 5 exhibited good volatility and stability.

show abstract

Section: Crystal Structure Ofmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Synthesis of Mono‐Imido Tungsten Complexes Directly from WCl₆

et al. 2016

View full text Add to dashboard Cite

show abstract

“…25,26 We now report the deposition of WN x C y thin films from the related complex, WN(NEt 2 ) 3 , for low temperature diffusion barrier and contact applications. z E-mail: tim@ufl.edu…”

mentioning

confidence: 99%

Low Temperature Deposition of WN_xC_yDiffusion Barriers Using WN(NEt₂)₃as a Single-Source Precursor

O’Donohue

McClain

Koley

et al. 2014

ECS J. Solid State Sci. Technol.

View full text Add to dashboard Cite

Deposition of high quality WN x C y barrier films at very low temperature using aerosol-assisted chemical vapor deposition (AACVD) is reported. The single-source tungsten nitrido complex, WN(NEt 2 ) 3 , was designed to reduce the temperature required for WN x C y film deposition in an effort to minimize thermal stresses on neighboring layers in device structures. Using either pyridine or heptane as a solvent, WN x C y films were successfully deposited at temperatures from 100 to 650 • C. Film growth in pyridine and heptane at low temperature (100-350 • C and 125-550 • C, respectively) showed weak temperature dependence consistent with mass-transfer limited growth. At higher temperature the growth rate decreased rapidly with apparent activation energy of 0.375 ± 0.057 eV. The effects of solvent choice on film properties including composition, crystallinity, density, and surface roughness are discussed. Films deposited at low temperature (<350 • C) were highly smooth, amorphous and with a stoichiometry approaching W 2 NC; characteristics desirable for diffusion barrier applications. In Cu diffusion barrier tests, Cu (∼ 100 nm)/WN x C y (∼ 5.5 nm)/Si stacks subjected to a 500 Thin interlayer materials are increasingly being used in electronic devices to modify interfacial characteristics, including the film work function, chemical, thermal and charge transport rates, surface tension, and adhesion. Due to their low resistivity, appropriate work function, and thermal stability, refractory metal nitrides have been proposed for a number of applications, ranging from wafer level hermetic sealing 1 to field effect transistor (FET) gate electrodes. 2 In particular, the tungsten-based materials WN x and WN x C y have been considered as an alternative for both diffusion barriers 3,4 and gate electrodes 5 due to their low resistivity, appropriate and tunable work function (4.39-5.01 eV 6 ), thermal and mechanical stability, good barrier performance, and processing simplicity. 7,8 Depositions of WN x and WN x C y typically use ammonia and WCl 6 , WF 6 or W(CO) 6 as co-reactants. 4,[9][10][11][12] Despite being volatile, simple, and cost-effective, these chemistries generally require high deposition temperature, can introduce impurities, and can yield corrosive byproducts. To overcome these drawbacks, organometallic precursors have drawn considerable interest for metal-organic CVD (MOCVD). Typically, these complexes include nitrogen-bound moieties such as amido, imido, hydrazido, amidinate or guanidinate ligands, 13,14 and have been used in single-source or NH 3 /H 2 co-reacting conditions to deposit WN x . Unfortunately, many of these precursors still require relatively high deposition temperature (>350• C) 15-22 that can compromise contact level structures 2,23 and neighboring dielectrics. 24In addition, the development of ultra-low temperature CVD WN x C y has potential application to flexible and organic devices. Therefore, there is interest in developing organometallic precursors for ultra-low deposition temperature. We h...

show abstract

Pitfalls and Limitations in Group 6 Triamidophosphane Chemistry: Cage‐Closure Restrictions in Square‐Pyramidal Nitrido Complexes and Degradation via Spiro‐[4.4]‐λ⁵‐Amidophosphorane Formation

et al. 2017

View full text Add to dashboard Cite

The benzylene-linked triaminophosphanes P(C 6 H 4 -o-CH 2 NHXyl) 3 ([A]H 3 ) and P(CH 2 C 6 H 4 -o-NHPh) 3 ([B]H 3 ) react with (Me 2 N) 3 Mo≡N to afford the square-pyramidal nitrido complexes 1 and 2, each comprising one residual dimethylamido moiety and one uncoordinated ligand sidearm. Only the [A]-coordinated complex 1 was found to eliminate the remaining dimethylamido ligand on heating. Instead of the closed-cage molybdenum(VI) nitrido complex [A]Mo≡N, cyclometalated molybdaziridine 3 was isolated, as the syn alignment of the uncoordinated sidearm and nitrido ligand in 1 inhibits a pro- [a] 5442 [20] ]. Therefore, we decided to Scheme 2. Established routes to [NN 3 ]-coordinated molybdenum nitrido complexes.

show abstract

Synthesis of WN(NMe₂)₃ as a Precursor for the Deposition of WN_x Nanospheres

Cited by 24 publications

References 63 publications

Synthesis of Mono‐Imido Tungsten Complexes Directly from WCl₆

Synthesis of Mono‐Imido Tungsten Complexes Directly from WCl₆

Low Temperature Deposition of WN_xC_yDiffusion Barriers Using WN(NEt₂)₃as a Single-Source Precursor

Pitfalls and Limitations in Group 6 Triamidophosphane Chemistry: Cage‐Closure Restrictions in Square‐Pyramidal Nitrido Complexes and Degradation via Spiro‐[4.4]‐λ⁵‐Amidophosphorane Formation

Contact Info

Product

Resources

About

Synthesis of WN(NMe2)3 as a Precursor for the Deposition of WNx Nanospheres

Cited by 24 publications

References 63 publications

Synthesis of Mono‐Imido Tungsten Complexes Directly from WCl6

Synthesis of Mono‐Imido Tungsten Complexes Directly from WCl6

Low Temperature Deposition of WNxCyDiffusion Barriers Using WN(NEt2)3as a Single-Source Precursor

Pitfalls and Limitations in Group 6 Triamidophosphane Chemistry: Cage‐Closure Restrictions in Square‐Pyramidal Nitrido Complexes and Degradation via Spiro‐[4.4]‐λ5‐Amidophosphorane Formation

Contact Info

Product

Resources

About

Synthesis of WN(NMe₂)₃ as a Precursor for the Deposition of WN_x Nanospheres

Synthesis of Mono‐Imido Tungsten Complexes Directly from WCl₆

Synthesis of Mono‐Imido Tungsten Complexes Directly from WCl₆

Low Temperature Deposition of WN_xC_yDiffusion Barriers Using WN(NEt₂)₃as a Single-Source Precursor

Pitfalls and Limitations in Group 6 Triamidophosphane Chemistry: Cage‐Closure Restrictions in Square‐Pyramidal Nitrido Complexes and Degradation via Spiro‐[4.4]‐λ⁵‐Amidophosphorane Formation