Gas products and carbon deposition kinetics in chemical vapor deposition from propylene

ABSTRACTTcrtiarybutylarsine (TBA) and tertiarybutylphosphine (TBP) were evaluated as n-type dopant precursors for low pressure chemical vapor deposition (LPCVD) of in situ doped amorphous and polycrystalline silicon from silanc. The deposition kinetics, film composition, and electrical properties obtained with TBA and TBP dopant precursors are compared to that obtained when using arsine and phosphine as dopant precursors. Compared to the hydride dopant sources, TBA and TBP provide increased safety due to their sub-atmospheric vapor pressure (≃ 200 Torr at 26°C) and lower toxicity. Using mixtures of TBA and TBP with silane and hydrogen, high quality films of arsenic and phosphorus in situ doped amorphous and polycrystalline silicon were obtained. Dopant incorporation levels ranged from 5×1019 to l.5×1021 cm−3 as measured by SIMS. The deposition rate of polycrystallinc films deposited from TBA and TBP was enhanced by a factor of-≃-3X compared to the hydride dopants for the same mole fraction of dopant precursor. The minimum resistivitics of 5.0 and 1.4 mΩ-cm were obtained, following a 1000°C, 30 second rapid thermal anneal, for ≃500Å thick films on SiO2 deposited with TBA and TBP respectively. A drawback of TBA and TBP is the incorporation of ≃1.0 atomic percent carbon which is > 15X higher than obtained when using the hydride dopant sources. Carbon was observed under all deposition conditions examined.

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Microstructure and deposition kinetics of Nb prepared by chemical vapor deposition

Modern Physics Letters B ◽

10.1142/s0217984918502573 ◽

2018 ◽

Vol 32 (22) ◽

pp. 1850257 ◽

Cited By ~ 2

Author(s):

Yan Wei ◽

Da Wei Zhang ◽

Jun Wang ◽

Hong Zhong Cai ◽

Xu Xiang Zhang ◽

...

Keyword(s):

Grain Size ◽

Chemical Vapor Deposition ◽

High Temperature ◽

Low Temperature ◽

Deposition Rate ◽

Vapor Deposition ◽

Deposition Temperature ◽

Chemical Vapor ◽

Deposition Kinetics ◽

Hydrogen Flow

The deposition kinetics and microstructure of chemical vapor deposition (CVD) of Nb on the Mo substrate at different deposition variables is investigated. The morphology of CVD Nb is columnar, it exhibits a strong preferred orientation and its growth direction is perpendicular to the substrate surface, the deposition rate and grain size increased with the increase of deposition temperature. The deposition rate conforms to the Arrhenius formula, the activation energy [Formula: see text] at high temperature and low temperature is 0.85 kJ/mol and 7.2 kJ/mol, respectively. The rate-limiting step for CVD Nb at high temperature is chemical reaction step, whereas that is the mass transport step at low temperature. Chlorination temperature has a weak influence on deposition rate and grain structure, the deposition rate and grain size of CVD Nb increased with the increase of the chlorine flow and hydrogen flow, the maximum deposition rate is [Formula: see text], thus, the optimum deposition temperature is 1200[Formula: see text]C, chlorination temperature is 350[Formula: see text]C, hydrogen flow is 400 ml, chlorine flow is 200 ml.

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