Decomposition of 1,1‐dimethyl‐1‐silacyclobutane on a tungsten filament—evidence of both ring CC and ring SiC bond cleavages

Tong, Ling; Shi, Yujun

doi:10.1002/jms.1712

Cited by 28 publications

(39 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is clearly visible in Fig. To our knowledge, this is the first time methane formation has been confirmed when using either open-chain alkylsilanes 14,20,21 or four-membered-ring (di)silacyclobutanes 19,[23][24][25][26] as an independent precursor gas in the hot-wire CVD process. With 4.0 Torr of TriMS, new peaks at m/z 16, 28, 40, and 42 were observed.…”

Section: A Formation Of Methane and Other Small Hydrocarbon Moleculesmentioning

confidence: 56%

Effect of trimethylsilane pressure on hot-wire chemical vapor deposition chemistry using vacuum ultraviolet laser ionization mass spectrometry

Toukabri

Shi

2013

Journal of Vacuum Science &Amp; Technology A: Vacuum, Surfaces, and Films

View full text Add to dashboard Cite

Detecting free radicals during the hot wire chemical vapor deposition of amorphous silicon carbide films using single-source precursors J. Vac. Sci. Technol. A 24, 542 (2006); 10.1116/1.2194023 Vacuum ultraviolet mass-analyzed threshold ionization spectroscopy of hexafluorobenzene: The Jahn-Teller effect and vibrational analysisIn this study, the authors investigated the effect of sample pressure on the reaction chemistry of trimethylsilane (TriMS) in the hot-wire chemical vapor deposition (CVD) process. The secondary gasphase reaction products were examined in a reactor with varying TriMS pressures. The reaction products were analyzed using a laser ionization source with a vacuum ultraviolet wavelength of 118 nm, coupled with mass spectrometry. By increasing TriMS pressure, methane formation was observed. To our knowledge, this is the first successful use of either open-chain alkylsilanes or four-membered-ring (di)silacyclobutane molecules as an independent precursor gas in the hot-wire CVD reactor to achieve methane formation. Our results showed that methane was formed mainly from the radical chain reactions with minor contributions from molecular elimination. The increase in the sample pressure also led to the formation of other small hydrocarbon molecules including acetylene, ethene, propyne, and propene. The formation of hydrogen molecules was enhanced when the sample pressure was increased. In addition, the change in the sample pressure had a direct effect on the radical recombination and disproportionation reactions. This is reflected in the different behavior assumed by the main products from these two types of reactions, i.e., tetramethylsilane, hexamethyldisilane from the former, and three methyl-substituted disilacyclobutanes from the latter. The trapping of free radicals resulting from the in-situ produced ethene and propene molecules is responsible for the observed difference.

show abstract

Section: A Formation Of Methane and Other Small Hydrocarbon Moleculesmentioning

confidence: 56%

Effect of trimethylsilane pressure on hot-wire chemical vapor deposition chemistry using vacuum ultraviolet laser ionization mass spectrometry

Toukabri

Shi

2013

Journal of Vacuum Science &Amp; Technology A: Vacuum, Surfaces, and Films

View full text Add to dashboard Cite

show abstract

“…In the decomposition of H 2 O, the production of OH and H is major at low catalyst temperatures, but H and O production becomes more dominant at high temperatures [37]. As for organosilicon compounds, selective and efficient decomposition is possible [51][52][53][54][55][56][57]. The decomposition paths are different from those in thermal decomposition.…”

Section: Discussion and Future Prospectsmentioning

confidence: 95%

Gas-phase diagnoses in catalytic chemical vapor deposition (hot-wire CVD) processes

Umemoto

2015

Thin Solid Films

View full text Add to dashboard Cite

a b s t r a c tRadical species play key roles in chemical vapor deposition (CVD) processes, including catalytic CVD (hot-wire CVD), and evaluating their densities in the gas phase is important in understanding the underlying mechanisms and controlling the processes. There are many diagnosis techniques to detect radical species. Among them, photon-in-photon-out techniques, including one-and two-photon laser-induced fluorescence and photoabsorption, can be utilized under the low vacuum conditions typical in CVD processes. Highly sensitive, quantitative, state-specific, real-time, and non-intrusive detection is possible with these techniques; even spatial resolution can be obtained in some cases. At the same time, however, we should know the drawbacks and the limitations of such techniques. A compilation of the radical species detected so far in catalytic CVD processes is presented in a table.

show abstract

“…[18][19][20] Briefly, to probe gas-phase species formed from secondary gas-phase reactions, a cylindrical HWCVD reactor is used. This reactor houses a resistively heated tantalum filament (Aldrich; 99.9+%, length = 10 cm, diameter = 0.5 mm) and is incorporated into the main ionization chamber with a linear TOF mass spectrometer (R.M.…”

Section: Experimental Methodsmentioning

confidence: 99%

Effect of pressure on the gas-phase chemistry when using monomethylsilane and dimethylsilane in hot-wire chemical vapor deposition

ToukabriRim

ShiYujun

2015

Can. J. Chem.

View full text Add to dashboard Cite

The effect of source gas pressure on the gas-phase reaction chemistry of dimethylsilane (DMS) and monomethylsilane (MMS) in the hot-wire chemical vapor deposition process has been studied by examining the secondary gas-phase reaction products in a reactor using a soft laser ionization source coupled with mass spectrometry. For DMS, the increase in sample pressure has resulted in the formation of small hydrocarbons, including ethene, acetylene, propene, and propyne. This leads to a switch from silylene dominant chemistry to a free radical dominant one with the pressure increase at low filament temperatures of 1200 and 1300°C. At the lower pressure of 0.12 Torr, the formation of 1,1,2,2-tetramethyldisilane by dimethylsilylene insertion reaction into the Si-H bond in DMS is favored over trimethylsilane produced from a free radical recombination reaction for a short reaction time. However, when the pressure is increased by 10 times, the gas-phase chemistry becomes dominated by the formation of trimethylsilane. We have demonstrated that trapping of the corresponding active intermediates by the small hydrocarbons produced in situ is responsible for the observed switch. In the study with MMS, the gas-phase chemistry is dominated by the formation of 1,2-dimethyldisilane and 1,3-disilacyclobutane at both pressures of 0.48 and 1.2 Torr. Unlike DMS, the gas-phase reaction chemistry with MMS does not involve free radicals, which are the precursors to produce small hydrocarbons. The absence of small hydrocarbons formed in situ with MMS explains the preservation in chemistry upon the increase in pressure when MMS is used as a source gas.Résumé : On a étudié dans un réacteur l'effet de la pression du gaz source sur la réaction en phase gazeuse du diméthylsilane (DMS) et du monométhylsilane (MMS) par un procédé de dépôt chimique en phase vapeur à fil chaud, en étudiant les produits secondaires dans la phase gazeuse au moyen d'un laser de faible puissance utilisé comme source d'ionisation et couplé avec un spectromètre de masse. Dans le cas du DMS, l'augmentation de la pression de l'échantillon a entraîné la formation d'hydrocarbures légers, notamment l'éthène, l'acétylène, le propène et le propyne. On en déduit que l'environnement chimique où la formation du silylène prédomine passe à un environnement chimique où la formation de radicaux libres prédomine dans lequel une augmentation de la pression s'est produite à de basses températures du filament (1200 et 1300°C). À la pression la plus faible (0,12 Torr), pendant un temps de réaction court, la formation du 1,1,2,2-tétraméthyldisilane par réaction d'insertion du diméthylsilylène dans le lien Si−H du DMS a été favorisée, par rapport à la formation du triméthylsilane issu de la réaction de recombinaison de radicaux libres. Toutefois, lorsque la pression était décuplée, la formation en phase gazeuse du triméthylsi-lane était prédominante. Nous avons démontré que le piégeage des intermédiaires réactifs par les hydrocarbures légers produits in situ est responsable du changement obse...

show abstract

Decomposition of 1,1‐dimethyl‐1‐silacyclobutane on a tungsten filament—evidence of both ring CC and ring SiC bond cleavages

Cited by 28 publications

References 39 publications

Effect of trimethylsilane pressure on hot-wire chemical vapor deposition chemistry using vacuum ultraviolet laser ionization mass spectrometry

Effect of trimethylsilane pressure on hot-wire chemical vapor deposition chemistry using vacuum ultraviolet laser ionization mass spectrometry

Gas-phase diagnoses in catalytic chemical vapor deposition (hot-wire CVD) processes

Effect of pressure on the gas-phase chemistry when using monomethylsilane and dimethylsilane in hot-wire chemical vapor deposition

Contact Info

Product

Resources

About