Synthesis and application of group v metal-containing formulations (R1N)m(n(R2R3))x(OR4)3-x with reduced (R1N)m(OR4)3 and (R1N)m(n(R2R3))3 content

Abstract

A chemical composition having booth (R1N)M(N(R2R3))2(OR4)I and (R1N)M(N(R2R3))I(OR4)2, the chemical composition further having less than five molar percent (5 Mol. %) of (R1N)Nb(N R2R3)3; and less than 3 Mol. % of (R1N)Nb(OR4)3. Use of the chemical composition as a vapor phase deposition precursor to deposit M containing materials such as Niobium Oxide.

Description

SYNTHESIS AND APPLICATION OF GROUP V METAL-CONTAINING FORMULATIONS (R1N)M(N(R2R3))x(OR4)3-x WITH REDUCED (R1N)M(OR4)3AND (R1N)M(N(R2R3))3CONTENTTechnical FieldThe technical field is the synthesis of chemicals, specifically high purity chemical for use in the semiconductor manufacturing industry.Background ArtNiobium oxide, niobium nitride thin films have a significant utilization in fabrication of microelectronic devices, batteries and catalysts, where the film is deposited by metal organic chemical vapor deposition (MOCVD), atomic layer deposition (ALD), plasma enhanced ALD and other deposition methods. In order to be applied at the industrial scale the thin film deposition processes need to be stable, reproducible and produce films of consistent quality.(fBuN)Nb(NEt2)x(OfBu)3-x (x = 0 - 3), and the subgenus (x = 1-2), are established chemicals used a precursors for vapor phase deposition of Nb films. See, e.g., US 10106887 B2. While some of these chemicals are commercially used as precursors, in particular for Nb2O5films, problems with process efficiency and reproducibility exist. Specifically, the “growth per cycle” or “GPC” for atomic layer deposition (“ALD”) processes has proven to be variable under defined and carefully controlled conditions, adding an undesirable variable to volume manufacturing operations.A problem to be solved is therefore to determine the source / cause of the aforementioned GPC variability and, based on this new understanding, to devise a means of reducing or eliminating the current GPC variability in ALD processes for coating surfaces with Nb films, primarily Niobium Oxide and Niobium Nitride films.(fBuN)Nb(NEt2)x(OfBu)3-x (x = 0 - 3) precursors are synthesized by several prior art routes and generally sold as highly pure single chemical compositions. One reason for this preferred approach is that each species has its own distinct vapor deposition behaviors, in particular for the GPC (if any) achievable in ALD processes.The general chemistry applied in US10106887B2 is disclosed in US20110087039A2,

[0013] ,

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[0065] :M1(NR1)(NR3R4)3+ R2OH M1(NR1)(OR2)3+ 3HN R3R4Ex. (fBuN)Nb(NEt2)3+ 3HOfBu = (fBuN)Nb(OfBu)3+ 3HNEt2(fBuN)Nb(NEt2)x(OfBu)3-x (x = 1 - 2) may be synthesized using this same approach. US10106887B2, Col. 19, line 54, - Col. 29, line 22. These reaction products are then subjected to routine distillation purification. Table 1 lists a comparison of chemical partial vapor pressures. The temperatures inducing a 0.1 Torr vapor pressure in each are near or overlapping with one another. This suggests distillation separation to 99% or greater purity is likely not possible without commercially unacceptable product losses.Table 1. Volatilities of (RN)Nb(NEt2)x(OfBu)3-x(x = 0 - 3)The inventors hypothesized that the current precursor products were in fact either starting out as post distillation mixtures of (fBuN)Nb(NEt2)x(OfBu)3.x(x = 0 - 3), or becoming so over time (compositional drift), or both. These variable contents would explain the variable GPC rates seen in ALD processes.Summary of InventionThe invention may be understood in relation to the following embodiments presented as numbered SENTENCES:1. A chemical composition comprising (R1N)M(N(R2R3))2(OR4)I and (R1N)M(N(R2R3))I(OR4)2, the chemical composition further comprisinga) less than five molar percent (5 Mol. %) of (R1N)Nb(N R2R3)3, preferably less than 3 Mol. %, more preferably 1 Mol. % or less, andb) less than 3 Mol. % of (R1N)Nb(OR4)3, preferably less than 2 Mol. %, more preferably 1 Mol. % or less; andc) wherein M is selected from Group 5 transition metals consisting of V, Nb, or T a and each R1, R2, R3, R4is independently selected from H; a C1 -C6 linear, branched, or cyclic alkyl group; a C1-C6 linear, branched, or cyclic alkylsilylgroup (mono, bis, or tris alkyl); a C1-C6 linear, branched, or cyclic alkylamino group; ora C1-C6 linear, branched, or cyclic fluoroalkyl group. The chemical composition of SENTENCE 1, wherein the chemical composition comprises (R1N)M(N(R2R3))2(OR4)I at 20 Mol. % to 60 Mol. % and (R1N)M(N(R2R3))I(OR4)2at 30 Mol % to 70 Mol %.The chemical composition of SENTENCE 1, wherein the chemical composition comprises (R1N)M(N(R2R3))2(OR4)I at 25 Mol. % to 45 Mol. % and (R1N)M(N(R2R3))I(OR4)2at 50 Mol % to 70 Mol %.The chemical composition of any one of SENTENCES 1-3, wherein the (R1N)M(N(R2R3))2(OR4)I comprises (fBuN)Nb(NEt2)2(OfBu) and the (R1N)M(N(R2R3))I(OR4)2comprises (fBuN)Nb(NEt2)(OfBu)2.The chemical compostion of SENTENCE 4, wherein the (R1N)Nb(N R2R3)3comprises (fBuN)Nb(NEt2)3and the (R1N)Nb(OR4)3comprises (fBuN)Nb(OfBu)3. The chemical composition of any one of SENTENCES 1-3, wherein M is selected from Nb or Ta.The chemical composition of SENTENCE 6, wherein R1, R4are selected from tertbutyl, isopropyl, and isobutyl groups; and R2, R3are selected from ethyl and propyl groups.The chemical composition of any one of SENTENCES 1-7, having an aggregate Mol. % of 95% or more, preferably 99% or more, more preferably 99.7% or more, for the (R1N)M(N(R2R3))2(OR4)I, the (R1N)M(N(R2R3))I(OR4)2, the (R1N)M(N R2R3)3, and the (R1N)M(OR4)3.The chemical composition of any one of SENTENCES 1-8, comprising less than 1 part per million of metals other than M, preferably 100 parts per billion or less. Use of the chemical compositions, of any one of SENTENCES 1-9, as an M precursor for a vapor deposition process to deposit an M containing material on a substrate, such as a coating or a film on the substrate.The use of SENTENCE 10, wherein the vapor deposition process is an atomic layer deposition process and the deposited M containing material is an M oxide, such as Nb2O5, an M oxynitride, such as a NbON, or an M nitride, such as NbN. A vapor deposition process for forming an M containing material on a substrate, the vapor deposition process comprising the steps of:a) exposing a substrate to a vapor of the chemical composition of any one of SENTENCES 1-9,b) forming the M containing material on the substrate by the vapor deposition process.13. The vapor deposition process of SENTENCE 12, wherein the M containing material formed is an M oxide, such as Nb2O5, an M oxynitride, such as a NbON, or an M nitride, such as NbN.14. The vapor deposition process of SENTENCE 12 or SENTENCE 13, wherein the vapor deposition process is an atomic layer deposition process.15. A method of synthesizing the chemical composition of any one of SENTENCES 1- 9, the method comprising the steps of:a) Combining (R1N)Nb(N R2R3)3with from 1.5 to 1.9 equivalents of R4OH to produce a crude synthesis product.16. The method of SENTENCE 15, further comprising fractional distillation of the crude synthesis product for produce the chemical composition.Disclosure of InventionThe inventors acquired and analyzed product from multiple sources that used the synthesis process of US10106887B2. There was a range of composition variation and none of the samples were >99% (fBuN)Nb(NEt2)x(OfBu)3.x, x = 1 or 2.Table 2 - Results from Multiple Lots of Commercial ProductThe inventor’s analysis revealed that these products were in fact mixtures with some variability. The inventors theorized that the above was due to the nature of the reactions used to produce the target molecules:(fBuN)Nb(NEt2)3+ 3HOfBu(fBuN)Nb(NEt2)2(OfBu) + HNEt2+ 2HOfBu (fBuN)Nb(NEt2)1(OfBu)2+ 2HNEt2+ 1HOfBu(fBuN)Nb(OfBu)3+ 3HNEt2Reaction kinetics and equilibria will limit the yield of (fBuN)Nb(NEt2)2(OfBu) compared to the reaction starting molecules and to the next reaction product of (fBuN)Nb(NEt2)1(OfBu)2. Due to the relative amounts and close boiling points, the resulting distillation products have compositions as shown in Table 2.The inventors conceived a different synthesis strategy to address this issue. The ALD behaviors of (fBuN)Nb(NEt2)2(OfBu) and (fBuN)Nb(NEt2)1(OfBu)2are similar enough to be viable as a two molecule ALD precursor mixture, if the proportions could be controlled to a consistent ratio range. In contrast, (fBuN)Nb(NEt2)3and (fBuN)Nb(OfBu)3require substantially different vapor deposition conditions. See Yotsuya, Tadahiro, et al. "Novel highly volatile MOCVD precursors for Ta2O5 and Nb2O5 thin films." ECS Transactions 16.5 (2008): 243; Basuvalingam, Saravana Balaji, et al. "Comparison of thermal and plasma-enhanced atomic layer deposition of niobium oxide thin films." Journal of Vacuum Science & T echnology A 36.4 (2018).Thus the inventors determined that the variability in GPC for ALD of Nb films could be reduced or eliminated, if synthesis conditions could be optimized to enable a post distillation composition with as little (fBuN)Nb(NEt2)3and (fBuN)Nb(OfBu)3and whatever reproducible ratio of (fBuN)Nb(NEt2)2(OfBu) and (fBuN)Nb(NEt2)1(OfBu)2that results from this synthesis. A secondary benefit of this approach is the reduction or even elimination of measurable composition drift, over a commercial shelf life timeframe, due to residual reaction components continuing to produce reaction products at varying rates.As detailed below, the inventors determined that the desired compositions could be attained by selecting a specific ratio of starting reagents (fBuN)Nb(NEt2)3+ HOfBu under standard conditions:A ratio of > 1.5 to < 1.9, such as 1.6 to 1.8, and exemplified by 1.7, yielded final distillation purification products having substantially reduced amounts of (fBuN)Nb(NEt2)3and (fBuN)Nb(OfBu)3compared to the prior art, with the above reproducible proportions of the two desired reaction products (fBuN)Nb(NEt2)2(OfBu) and (fBuN)Nb(NEt2)1(OfBu)2.The resulting compositions using a 1.7 ratio were shelf stable in an accelerated aging study for 21 days at 90 degrees C. This demonstrates the secondary benefit of substantially reduced composition drift due to ongoing reactions.Finally, ALD reactions with these novel compositions yielded a stable GPC rate that saturated in a pulse dose study, demonstrating improved ALD results over the prior art compositions.Mode(s) for Carrying Out the InventionThe inventors performed the following exemplary experiments that support the invention claimed herein.Comparative Example 1. Reaction of BuN)Nb(NEt2)3and 1 Equivalent 'BuOH (1:1 ratio).The inventors synthesized (fBuN)Nb(NEt2)2(OfBu) according to the synthesis process of US10106887B2.To a solution of (fBuN)Nb(NEt2)3(33.32 g, 87.59 mmol) in 150 mL THF at -78 °C, a solution offBuOH (6.5 g, 87.70 mmol) in ca. 200 mL THF was added dropwise. The reaction mixture was warmed to room temperature and stirred overnight. Then the solvent and volatiles were evaporated to give a yellow oil. The yellow oil was purified by distillation under vacuum; the forecut was collected at 58 - 94 °C / 140 mTorr. The main cut being the colorless oil was collected at 98 - 102 °C / 140 mTorr. Yield was 23.54 g.1H NMR, (C6D6, δ SiMe4, ppm): 3.51 (m, doublet of septets, J = 7 Hz, NCH2CH3, rel. int. 8.00), 1.41, 1.38, 1.37 (overlapped singlets, OC(CH3)3, rel. int. 19.67), 1.20, 1.16, 1.15, 1.14 (overlapped triplets, J = 7 Hz, rel. int. 11.63). Comparison of the obtained1H NMR of the product with the NMR spectra of (fBuN)Nb(NEt2)3, (fBuN)Nb(NEt2)(OfBu)2revealed that the minor parts of triplet at 1.14, 1.16 ppm and singlet at 1.41 ppm are due to (fBuN)Nb(NEt2)3and minor triplet at 1.20 ppm is due to (fBuN)Nb(NEt2)(OfBu)2.The following approach was used to calculate the relative amounts of (fBuN)Nb(NEt2)3, (fBuN)Nb(NEt2)2(OfBu) and (fBuN)Nb(NEt2)(OfBu)2from overlapped1H NMR spectrum of the product: integrated ¼ = ICH3, Aof triplet at 1.20 ppm due to (fBuN)Nb(NEt2)(OfBu)2and ¼ = ICH3, Bof triplet at 1.14 ppm due to (fBuN)Nb(NEt2)3and the whole resonance of CH3[N(CH2CH3)2] = ICH3= 11.63; while ICH2= 8, corresponding to 8 protons in NEt2group. The calibrated (molar) intensities of complexes are:(fBuN)Nb(NEt2)2(OfBu) =(11.63 - 4ICH3, A- 4ICH3, B) / 12;(fBuN)Nb(NEt2)(OfBu)2= 4(ICH3, A) / 6;(fBuN)Nb(NEt2)3= 4(ICH3, B) / 18;The calibrated (molar) intensity of (fBuN)Nb(OfBu)3is calculated by difference from the overlapped singlets of -OfBu (ItBu= 19.67) in the area 1.37 - 1.41 ppm: (fBuN)Nb(OfBu)3= (ItBu- 27(4(ICH3, A) / 6) - 9(4(ICH3, B) / 18) - 18(11.63 - 4ICH3, A- 4ICH3, B) / 12)) / 36. Calculated is -0.23% for the product in row 1, hence (fBuN)Nb(OfBu)3is not present in the mixture assuming ±1% error.Comparative Example 1 - Relative amounts of (tBuN)Nb(NEt2)x(OtBu)3-x (x = 0 - 3) from1H NMR.This result is consistent with the commercial product analysis in Table 2 above. The (fBuN)Nb(NEt2)2(OfBu) contains substantial amounts of (fBuN)Nb(NEt2)3after purification.Comparative Example 2. Reaction of fBuN)Nb(NEt2)3and 2 Equivalents 'BuOH (1:2 ratio).The inventors synthesized (fBuN)Nb(NEt2)(OfBu)2according to the synthesis process of US10106887B2.To a solution of (fBuN)Nb(NEt2)3(2 g, 5.26 mmol) in 20 mL THF at -78 °C, a solution offBuOH (0.78 g, 10.52 mmol) in ca. 40 mL THF was added dropwise. The solution was warmed to room temperature and stirred overnight. The solvent and volatiles were evaporated to give yellow oil. It was subject to distillation at 70 - 80 °C and 150 - 200 mT orr to give colorless oil. Yield was 1.43 g.1H NMR, (C6D6, δ SiMe4, ppm): 3.50 (q, J = 7 Hz, NCH2CH3, rel. int. 4.00), 1.39, 1.38, 1.37 (overlapped singlets, OC(CH3)3, rel. int. 37.21), 1.18, 1.15 (overlapped triplets, J = 7 Hz, rel. int. 5.89).The relative amounts of (fBuN)Nb(NEt2)x(OfBu)3.x(x = 1 - 3) from1H NMR were calculated by the method from comparative example 1, sum of (fBuN)Nb(NEt2)x(OfBu)3.x(x = 1 - 3) is 100%. Integration of1H NMR spectrum revealed that the relative portion of (fBuN)Nb(NEt2)x(OfBu)3.x(x = 1 - 3) is 99.5%, the rest 0.5% is diethylamine and other niobium complexes.Comparative Example 2 - Relative amounts of (tBuN)Nb(NEt2)x(OtBu)3-x (x = 0 - 3) from1H NMR.Comparative Example 3. Deposition test.Thin film deposition tests were performed using a mixture containing 8% (fBuN)Nb(NEt2)2(OfBu), 82% (fBuN)Nb(NEt2)(OfBu)2and 10% (fBuN)Nb(OfBu)3, relative amounts determined by1H NMR. This mixture is representative of the prior art compositions sold as purified (fBuN)Nb(NEt2)2(OfBu). The mixture was placed in a vessel, attached to the deposition setup and was heated at 91 °C during the deposition process; niobium oxide film was deposited in tubular reactor. Deposition was performed on HF-cleaned bare Silicon. Typical deposition conditions were: reactor temperature 200, 225 and 250 °C in different tests, pressure in reactor 1 T orr, pressure in canister 40 T orr, carrier gas N2, flow rate 40 seem, co-reactant ozone, flow rate of co-reactant 50 seem, N2dilution flow rate 210 seem. Performed 100 - 300 cycles, duration of pulses of niobium precursor varied from 10 to 40 sec., then purge 60 sec, ozone pulse 10 sec., purge 30 sec.During the deposition process, at the precursor pulse 30 seconds and the reactor temperature 250 °C, the growth per cycle rate (GPC / Å) is constantly changing with the consumption of the precursor from 4.7 A per cycle at the beginning of deposition test to 3.80 A per cycle after 200 cycles and to 3.53 A per cycle after 250 cycles. In addition to that, at the above conditions, the GPC rate increased with the increase of precursor pulse. At 225 °C, the GPC rate changes from 1.5 to 2.2 A per cycle for precursor pulse times of 10 seconds, 20 seconds and 30 seconds. GPC saturation was also not observed at T= 250 °C.The lack of GPC saturation indicates the process is not an ALD process. The inventors believe that (fBuN)Nb(OfBu)3is depositing in a concurrent CVD process that may also at least partially prevent ALD reactions withfBuN)Nb(NEt2)2(OfBu) and (fBuN)Nb(NEt2)(OfBu)2. The variable GPC may reflect the consumption of (fBuN)Nb(OfBu)3in an initial CVD deposition and consequent shift over time to an ALD dominated deposition process by (fBuN)Nb(NEt2)2(OfBu) and (fBuN)Nb(NEt2)(OfBu)2. This variable type (CVD / ALD) and GPC rate will also vary based on the relative starting amounts of the (fBuN)Nb(NEt2)x(OfBu)3.x(x = 1 - 3) species present. Such a process is not suitable for a commercial semiconductor manufacturing process.Comparative Example 4. Reaction of BuN)Nb(NEt2)3and 3 Equivalents 'BuOH (1:3 ratio).The inventors synthesized (fBuN)Nb(OfBu)3according to the synthesis process of US7906668B2.To a neat (fBuN)Nb(NEt2)3(50 g, 131.4 mmol) at -10 °C, a solution offBuOH (29.2 g, 394.3 mmol) in 30 g of pentane was added dropwise. The solution was warmed to room temperature and stirred for 16 hours. The solvent and volatiles were evaporated to give yellow oil, which was distilled via the short path under vacuum at 96-108 °C (pot temperature) to give a colorless oil. Yield of the product is 50 g.1H NMR, (C6D6, δ SiMe4, ppm): 3.50 (q, J = 7 Hz, NCH2CH3, rel. int. 2.05, (fBuN)Nb(NEt2)(OfBu)2, 1.39, 1.38, 1.37 (overlapped singlets of (fBuN)Nb(NEt2)(OfBu)2and (fBuN)Nb(OfBu)3, OC(CH3)3, rel. int. 360.00), 1.19 (triplets J = 7 Hz, rel. int. 3.71, (fBuN)Nb(NEt2)(OfBu)2).The relative amounts of (fBuN)Nb(NEt2)(OfBu)2(6.1 Mol.%) and (fBuN)Nb(OfBu)3(93.9 Mol. %) were calculated by the method from comparative example 1.Similar to US10106887B2, the post distillation composition was not >99% (fBuN)Nb(OfBu)3, there was a substantial residual amount of co-distilled (fBuN)Nb(NEt2)(OfBu)2. However, the inventors believe that this mixture does not substantially affect the CVD behavior of the (fBuN)Nb(OfBu)3component and therefore a CVD deposition GPC variability is likely not seen.Comparative Example 5. Reaction of fBuN)Nb(NEt2)3and 3.18 Equivalents 'BuOH (1:3.18 ratio).The amount offBuOH was increased slightly to try to convert more of the (fBuN)Nb(NEt2)(OfBu)2to (fBuN)Nb(OfBu)3. After distillation, the synthesis produced Nb(OfBu)5(3.0 Mol.%) and (fBuN)Nb(OfBu)3(97.0 Mol.%), thus forming yet another, different co-purified Nb chemical. This result emphasizes the complex and unpredictable reactions occurring in these syntheses and the difficulty in obtaining single molecule compositions of high purity.Example 1. Reactions 1: 1 to 3 equivalent 'BuOHThe inventors performed a titration series of syntheses to ascertain if it was possible to produce, after distillation, a reaction product with less than 3 molar percent of the starting material (fBuN)Nb(NEt2)3and the further reaction product (fBuN)Nb(OfBu)3, thereby producing a composition with a defined ratio of (fBuN)Nb(NEt2)2(OfBu) and(fBuN)Nb(NEt2)(OfBu)2that would enable stable and reproducing ALD reactions (GPC in particular).The inventors used the same procedures from Comparative Examples 1-2, but with varying amounts of offBuOH. To a neat (fBuN)Nb(NEt2)3(3 g, 7.9 mmol) at -20 °C a neat offBuOH (corresponding to 1.0, 1.1, 1.5, 1.7, 1.9, 2.1, 3.0 equivalents) was added dropwise, all operations are in glove box with less than 0.5 ppm of oxygen and moisture. The solution was warmed to room temperature and stirred for 16 hours, then sampled for NMR in J Young tubes to get 5-10% w / w in C6D6.1H NMR (general), (C6D6, <5SiMe4, ppm): 3.50 (overlapped multiplets of NCH2CH3, total rel. int. 40), 2.47 (q, NCH2CH3of HHNEt2), 1.38, 1.37 (overlapped singlets of OC(CH3)3, rel. int. varies), 1.18, 1.16, 1.14 (overlapped triplets of NCH2CH3, total rel. int.60 for all multiplet, relative intensities of components varies), 0.98 (t, HNCH2CH3of HNEt2), 0.20 (br., HNCH2CH3of HNEt2).Example 1. Relative amounts on niobium complexes in the reaction products from reactions fBuN)Nb(NEt2)3+ nHOfBu (not purified by distillation).Surprisingly, by titrating the reactants in the 1:1.5 to 1:1.9 range, the crude synthesis products included less than five percent molar of (fBuN)Nb(NEt2)3and(fBuN)Nb(OfBu)3. 1:1.7 yielded the best result in this titration series with less than 3.0 Mol. % of each.Example 2. Reaction 1: 1.7 with the separation of products by distillationTo a neat (fBuN)Nb(NEt2)3(100 g, 262.9 mmol) at -10 °C a solution offBuOH (33.0 g, 445.0 mmol) in 66.3 g of pentane was added dropwise. The solution was warmed to room temperature and stirred for 16 hours. The solvent and volatiles were evaporated to give yellow oil, which was distilled via the short path under vacuum at 100-120 °C (pot temperature) to give colorless oil. Yield is 99 g.1H NMR, (C6D6, δ SiMe4, ppm): 3.50 (overlapped multiplets of NCH2CH3, total rel. int. 40.4), 1.39, 1.37 (overlapped singlets of OC(CH3)3, rel. int. 177.6), 1.19, 1.17 (overlapped triplets of NCH2CH3, total rel. int. 60 for all multiplet, relative intensities of components (1 / 4): 7.23 and 7.59), The relative amounts of (fBuN)Nb(NEt2)2(OfBu) (34.1 Mol.%), (fBuN)Nb(NEt2)(OfBu)2(64.9 Mol.%) and (fBuN)Nb(OfBu)3(0.7 Mol.%) were calculated by the method from Comparative Example 1. The relative portion of (fBuN)Nb(NEt2)x(OfBu)3.x(x = 0 - 3) in product by integration of1H NMR spectrum is 99.70%, relative amount of HNEt20.01%, other compounds 0.29%.With distillation, (fBuN)Nb(NEt2)3was below detection and (fBuN)Nb(OfBu)3was present at 0.7 molar percent (Mol.%). (fBuN)Nb(NEt2)2(OfBu): (fBuN)Nb(NEt2)(OfBu)2ratio was approximately 1:2.Example 3. Stability of mixture obtained in Example 2 (monitored by1HNMR).The inventors performed an accelerated aging evaluation with aliquots stored at room temperature, 60 degrees C and 90 degrees C, for 7, 14 and 21 days. The compositions were shelf stable, with no statistically significant changes, under the conditions tested. This confirmed that the composition drift seen with prior art commercial compositions had been prevented.Example 7. Deposition test with composition containing 1% of ('BuN)Nb(O'Bu)3.The thin film deposition tests were performed using the mixture containing 34% (fBuN)Nb(NEt2)2(OfBu), 64% (fBuN)Nb(NEt2)(OfBu)2and 1% (fBuN)Nb(OfBu)3. Relative amounts were determined by1H NMR (the content of formulation is close to that in Example 2). The mixture was placed in a vessel, attached to the deposition setup and was heated at 97 °C during all deposition process; niobium oxide film was deposited in tubular reactor. Deposition was performed on HF-cleaned bare Silicon. Typical deposition conditions were: reactor temperature 225 or 250 °C in different tests, pressure in reactor1 Torr, pressure in canister 40 Torr, carrier gas N2, flow rate 40 sccm, co-reactant ozone,flow rate of co-reactant 50 sccm, N2dilution flow rate 210 sccm. Performed 100 - 300cycles, duration of pulses of niobium precursor varied from 10 to 40 sec., then N2purged60 sec, ozone pulsed 10 sec., N2purged 30 sec. During the deposition process, at both temperatures the GPC saturation was observed in pulse dose time experiments (10, 20, 30 and 40 seconds), confirming an ALD deposition process. The saturated GPC rate at 225 °C was 1.5 Å and 2.6 Å at 250 °C. The GPC rate was stable, confirming that the new compositions eliminated the GPC variability over time seen with prior art commercial compositions.Industrial ApplicabilityThe present invention is at least industrially applicable to the synthesis of volatile Niobium chemicals suitable for use as atomic layer deposition precursors for Niobium Oxide and Niobium Nitride films / layers in semiconductors.While the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, it is intended to embrace all such alternatives, modifications, and variations as fall within the spirit and broad scope of the appended claims. The present invention may suitably comprise, consist or consist essentially of the elements disclosed and may be practiced in the absence of an element not disclosed. Furthermore, if there is language referring to order, such as first and second, it should be understood in an exemplary sense and not in a limiting sense. For example, it can be recognized by those skilled in the art that certain steps can be combined into a single step.All references identified herein are each hereby incorporated by reference into this application in their entireties, as well as for the specific information for which each is cited.Notation and NomenclatureThe following detailed description and claims utilize a number of abbreviations, symbols, and terms, which are generally well known in the art, and include:• The singular forms "a", "an" and "the" include plural referents, unless the context clearly dictates otherwise.• "Comprising" in a claim is an open transitional term which means the subsequently identified claim elements are a nonexclusive listing (i.e., anything else may be additionally included and remain within the scope of “comprising”). “Comprising”as used herein may be replaced by the more limited transitional terms "consisting essentially of and “consisting of unless otherwise indicated herein.• “Providing” in a claim is defined to mean furnishing, supplying, making available, or preparing something. The step may be performed by any actor in the absence of express language in the claim to the contrary.• Optional or optionally means that the subsequently described event or circumstances may or may not occur. The description includes instances where the event or circumstance occurs and instances where it does not occur.• Ranges may be expressed herein as from about one particular value, and / or to about another particular value. When such a range is expressed, it is to be understood that another embodiment is from the one particular value and / or to the other particular value, along with all combinations within said range.• As used herein, “about” or “around” or “approximately” in the text or in a claim means±10% of the value stated.• As used herein, “room temperature” in the text or in a claim means from approximately 20° C. to approximately 25° C.• The term “ambient temperature” refers to an environment temperature approximately 20° C. to approximately 25° C.• The term “substrate” refers to a material or materials on which a process is conducted. The substrate may refer to a wafer having a material or materials on which a process is conducted. The substrates may be any suitable wafer used in semiconductor, photovoltaic, flat panel, or LCD-TFT device manufacturing. The substrate may also have one or more layers of differing materials already deposited upon it from a previous manufacturing step. For example, the wafers may include silicon layers (e.g., crystalline, amorphous, porous, etc.), silicon containing layers (e.g., SiO2, SiN, SiON, SiCOH, etc.), metal containing layers (e.g., copper, cobalt, ruthenium, tungsten, platinum, palladium, nickel, ruthenium, gold, etc.) or combinations thereof. Furthermore, the substrate may be planar or patterned. The substrate may be an organic patterned photoresist film. The substrate may include layers of oxides which are used as dielectric materials in MEMS, 3D NAND, MIM, DRAM, or FeRam device applications (for example, ZrO2 based materials, HfO2 based materials, TiO2 based materials, rare earth oxide based materials, ternary oxide based materials, etc.) or nitride-based films (for example, TaN, TiN, NbN) that are used as electrodes. One of ordinary skill in the art will recognize that the terms “film” or “layer” used herein refer to a thickness of some material laid on orspread over a surface and that the surface may be a trench or a line. Throughout the specification and claims, the wafer and any associated layers thereon are referred to as substrates.• Note that herein, the terms “film” and “layer” may be used interchangeably. It is understood that a film may correspond to, or related to a layer, and that the layer may refer to the film. Furthermore, one of ordinary skill in the art will recognize that the terms “film” or “layer” used herein refer to a thickness of some material laid on or spread over a surface and that the surface may range from as large as the entire wafer to as small as a trench or a line.• The standard abbreviations of the elements from the periodic table of elements are used herein. It should be understood that elements may be referred to by these abbreviation (e.g., Si refers to silicon, N refers to nitrogen, O refers to oxygen, C refers to carbon, H refers to hydrogen, F refers to fluorine, etc.).• The unique CAS registry numbers (i.e., “CAS”) assigned by the Chemical Abstract Service are provided to identify the specific molecules disclosed.• As used herein, the term “hydrocarbon” refers to a saturated or unsaturated function group containing exclusively carbon and hydrogen atoms. As used herein, the term “alkyl group” refers to saturated functional groups containing exclusively carbon and hydrogen atoms, An alkyl group is one type of hydrocarbon. Further, the term “alkyl group” refers to linear, branched, or cyclic alkyl groups. Examples of linear alkyl groups include without limitation, methyl groups, ethyl groups, propyl groups, butyl groups, etc. Examples of branched alkyls groups include without limitation, t-butyl. Examples of cyclic alkyl groups include without limitation, cyclopropyl groups, cyclopentyl groups, cyclohexyl groups, etc.• As used herein, the abbreviation “Me” refers to a methyl group; the abbreviation “Et” refers to an ethyl group; the abbreviation “Pr” refers to any propyl group (i e., n-propyl or isopropyl); the abbreviation “iPr” refers to an isopropyl group; the abbreviation “Bu” refers to any butyl group (n-butyl, iso-butyl, tert-butyl, sec-butyl): the abbreviation “tBu” refers to a tert-butyl group; the abbreviation “sBu” refers to a sec-butyl group; the abbreviation “iBu” refers to an iso-butyl group; the abbreviation “Ph” refers to a phenyl group; the abbreviation “Am” refers to any amyl group (iso-amyl, sec-amyl, tert-amyl); the abbreviation “Cy” refers to a cyclic hydrocarbon group (cyclobutyl, cyclopentyl, cyclohexyl, etc.).• Please note that the silicon-containing films, such as Si, SiN, SiO, SiOC, SiON, SiCON, are listed throughout the specification and claims without reference to theirproper stoichiometry. The silicon-containing films may also include dopants, such as B, P, As, Ga and / or Ge. The fact that the film contains some residual hydrogen is also omitted from the film composition description. For instance, a SiOC film may contain residual H.• Ranges may be expressed herein as from about one particular value, and / or to about another particular value. When such a range is expressed, it is to be understood that another embodiment is from the one particular value and / or to the other particular value, along with all combinations within said range. Any and all ranges recited herein are inclusive of their endpoints (i.e., x=1 to 4 or x ranges from 1 to 4 includes x=1, x=4, and x=any number in between), irrespective of whether the term “inclusively” is used.• Reference herein to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the invention. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments necessarily mutually exclusive of other embodiments. The same applies to the term “implementation.”• As used herein, the term “independently” when used in the context of describing R groups should be understood to denote that the subject R group is not only independently selected relative to other R groups bearing the same or different subscripts or superscripts, but is also independently selected relative to any additional species of that same R group. For example in the formula MR1 x (NR2R3)(4-x), where x is 2 or 3, the two or three R1 groups may, but need not be identical to each other or to R2 or to R3. Further, it should be understood that unless specifically stated otherwise, values of R groups are independent of each other when used in different formulas.• As used in this application, the word “exemplary” is used herein to mean serving as an example, instance, or illustration. Any aspect or design described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects or designs. Rather, use of the word exemplary is intended to present concepts in a concrete fashion.• Additionally, the term “or” is intended to mean an inclusive “or” rather than an exclusive “or”. That is, unless specified otherwise, or clear from context, “X employs A or B” is intended to mean any of the natural inclusive permutations. That is, if Xemploys A; X employs B; or X employs both A and B, then “X employs A or B” is satisfied under any of the foregoing instances. In addition, the articles “a” and “an” as used in this application and the appended claims should generally be construed to mean “one or more” unless specified otherwise or clear from context to be directed to a singular form.

Claims

CLAIMS:

1. A chemical composition comprising (R1N)M(N(R2R3))2(OR4)I and (R1N)M(N(R2R3))I(OR4)2, the chemical composition further comprisinga) less than five molar percent (5 Mol. %) of (R1N)Nb(N R2R3)3, preferably less than 3 Mol. %, more preferably 1 Mol. % or less, andb) less than 3 Mol. % of (R1N)Nb(OR4)3, preferably less than 2 Mol. %, more preferably 1 Mol. % or less; andc) wherein M is selected from Group 5 transition metals consisting of V, Nb, or Ta and each R1, R2, R3, R4is independently selected from H; a C1-C6 linear, branched, or cyclic alkyl group; a C1-C6 linear, branched, or cyclic alkylsilyl group (mono, bis, or tris alkyl); a C1-C6 linear, branched, or cyclic alkylamino group; ora C1-C6 linear, branched, or cyclic fluoroalkyl group.

2. The chemical composition of claim 1, wherein the chemical composition comprises (R1N)M(N(R2R3))2(OR4)I at 20 Mol. % to 60 Mol. % and (R1N)M(N(R2R3))I(OR4)2at 30 Mol % to 70 Mol %.

3. The chemical composition of claim 1, wherein the chemical composition comprises (R1N)M(N(R2R3))2(OR4)I at 25 Mol. % to 45 Mol. % and (R1N)M(N(R2R3))I(OR4)2at 50 Mol % to 70 Mol %.

4. The chemical composition of any one of claims 1-3, wherein the (R1N)M(N(R2R3))2(OR4)I comprises (fBuN)Nb(NEt2)2(OfBu) and the (R1N)M(N(R2R3))I(OR4)2comprises (fBuN)Nb(NEt2)(OfBu)2.

5. The chemical composition of claim 4, wherein the (R1N)Nb(N R2R3)3comprises (fBuN)Nb(NEt2)3and the (R1N)Nb(OR4)3comprises (fBuN)Nb(OfBu)3.

6. The chemical composition of any one of claims 1-3, wherein M is selected from Nb or Ta.

7. The chemical composition of claim 6, wherein R1, R4are selected from tert-butyl, isopropyl, and isobutyl groups; and R2, R3are selected from ethyl and propyl groups.

8. The chemical composition of any one of claims 1-7, having an aggregate Mol. % of 95% or more, preferably 99% or more, more preferably 99.7% or more, for the (R1N)M(N(R2R3))2(OR4)I, the (R1N)M(N(R2R3))I(OR4)2, the (R1N)M(N R2R3)3, and the (R1N)M(OR4)3.

9. The chemical composition of any one of claims 1-8, comprising less than 1 part per million of metals other than M, preferably 100 parts per billion or less.

10. Use of the chemical compositions, of any one of claims 1 -9, as an M precursor for a vapor deposition process to deposit an M containing material on a substrate, such as a coating or a film on the substrate.

11. The use of claim 10, wherein the vapor deposition process is an atomic layer deposition process and the deposited M containing material is an M oxide, such as Nb2O5, an M oxynitride, such as a NbON, or an M nitride, such as NbN.

12. A vapor deposition process for forming an M containing material on a substrate, the vapor deposition process comprising the steps of:a) exposing a substrate to a vapor of the chemical composition of any one of claims 1-9,b) forming the M containing material on the substrate by the vapor deposition process.

13. The vapor deposition process of claim 12, wherein the M containing material formed is an M oxide, such as Nb2O5, an M oxynitride, such as a NbON, or an M nitride, such as NbN.

14. The vapor deposition process of claim 12 or claim 13, wherein the vapor deposition process is an atomic layer deposition process.

15. A method of synthesizing the chemical composition of any one of claims 1 -9, the method comprising the steps of:a) combining (R1N)Nb(N R2R3)3with from 1.5 to 1.9 equivalents of R4OH to produce a crude synthesis product.

16. The method of claim 15, further comprising fractional distillation of the crude synthesis product for produce the chemical composition.

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