Gas phase and surface kinetics in plasma enhanced chemical vapor deposition of microcrystalline silicon: The combined effect of rf power and hydrogen dilution

2001 ◽  
Vol 90 (11) ◽  
pp. 5786-5798 ◽  
Author(s):  
E. Amanatides ◽  
S. Stamou ◽  
D. Mataras
Keyword(s):  
Chemical Vapor Deposition ◽  
Gas Phase ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Combined Effect ◽  
Rf Power ◽  
Surface Kinetics ◽  
Microcrystalline Silicon ◽  
Hydrogen Dilution

Structural and optoelectronic properties of amorphous and microcrystalline silicon deposited at low substrate temperatures by RF and HW CVD

1999 ◽  
Vol 557 ◽  
Author(s):  
P. Alpuim ◽  
V. Chu ◽  
J. P. Conde
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Defect Density ◽  
Chemical Vapor ◽  
Optoelectronic Properties ◽  
Microcrystalline Silicon ◽  
Crystalline Fraction ◽  
Hydrogen Dilution ◽  
Structural And Optoelectronic Properties ◽  
Substrate Temperatures

AbstractThe structural and optoelectronic properties of silicon thin films prepared by hot wire chemical vapor deposition and radio frequency plasma enhanced chemical vapor deposition are studied in the range of substrate temperatures (Tsub)from 100 °C to 25 °C. The defect density, structure factor and bond angle disorder of amorphous silicon films (a-Si:H) deposited by both techniques are strongly improved by the use of hydrogen dilution. Correlation of these structural properties with important optoelectronic properties, such as photo-to-dark conductivity ratio, is made. Microcrystalline silicon (μc-Si:H) is obtained using HW with a large crystalline fraction for hydrogen dilutions above 85% independently of Tsub. The deposition of μc-Si:H by RF requires increasing the hydrogen dilution and shows decreasing crystalline fraction as Tsub is decreased. The properties of the low Tsub films are compared to those of samples produced at 175 °C and 250 °C in the same reactors.

Amorphous-to-Microcrystalline Silicon Transition in Hot-Wire Chemical Vapor Deposition

1995 ◽  
Vol 377 ◽  
Author(s):  
P. Brogueira ◽  
V. Chu ◽  
J. P. Conde
Keyword(s):  
Thin Films ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Hot Wire ◽  
Microcrystalline Silicon ◽  
Crystalline Fraction ◽  
Hydrogen Dilution ◽  
Process Pressure ◽  
Silicon Growth

ABSTRACTThe conductivity and the structural properties of thin films deposited by Hot-Wire Chemical Vapor Deposition (HW-CVD) from silane and hydrogen at a substrate temperature of 220 °C are shown to be strongly dependent on the filament temperature, Tfil, and process pressure, p. Amorphous silicon films are obtained at low pressures, p < 3 × 10−2Torr, for Tfil ∼ 1900 °C and FH2 = FSiH4. At this TfilJU, high deposition rates are observed, both with and without hydrogen dilution, and no silicon was deposited on the filaments. At Tfil ∼ 1500 °C, a transition from a-Si:H for p > 0.3 Torr to microcrystalline silicon (μc-Si:H) for p < 0.1 Torr occurs. In this temperature regime, silicon growth on the filaments is observed. /ic-Si:H growth both without hydrogen dilution and also in very thin films (∼ 0.05 μm) is achieved. Raman and X-Ray spectra give typical grain sizes of 10 – 20 nm, with a crystalline fraction higher than 50%. For both, Tju ∼ 1500 °C, p > 0.3 Torr and Tfil ∼ 1900 °C and p ∼ 2.7 × 10−2Torr, an increase of the crystalline fraction from 0 to ∼ 30% is observed when the hydrogen dilution, FH2/FSiH4, increases from 1 to > 4.

Kinetics of Diamond-Like Film Growth Using Filament-Assisted Chemical Vapor Deposition

1994 ◽  
Vol 363 ◽  
Author(s):  
G. Gorsuch ◽  
Y. Jin ◽  
N. K. Ingle ◽  
T. J. Mountziarisi ◽  
W.-Y. Yu ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Kinetic Model ◽  
Gas Phase ◽  
Vapor Deposition ◽  
Film Growth ◽  
Transport Model ◽  
Surface Reactions ◽  
Chemical Vapor ◽  
Surface Kinetics ◽  
Si Substrates

AbstractA detailed kinetic model of diamond-like film growth from methane diluted in hydrogen using low-pressure, filament-assisted chemical vapor deposition (FACVD) has been developed. The model includes both gas-phase and surface reactions. The surface kinetics include adsorption of CH3· and H·, abstraction reactions by gas-phase radicals, desorption, and two pathways for diamond (sp3) and graphitic carbon (sp2) growth. It is postulated that adsorbed CH2· species are the major film precursors. The proposed kinetic model was incorporated into a transport model describing flow, heat and mass transfer in stagnation flow FACVD reactors. Diamond-like films were deposited on preseeded Si substrates in such a reactor at a pressure of 26 Torr, inlet gas composition ranging from 0.5% to 1.5% methane in hydrogen and substrate temperatures ranging from 600 to 950°C. The best films were obtained at low methane concentrations and substrate temperature of 700°C. The films were characterized using Scanning Electron Microscopy (SEM) and Raman spectroscopy. Observations from our experiments and growth rate data from similar experiments reported in the literature [1] were used to estimate unknown kinetic parameters of surface reactions. The proposed model predicts observed film growth rates, compositions and stable species distributions in the gas phase. It is the first complete model of FACVD that includes gas-phase and surface kinetics coupled with transport phenomena.

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