Si-H Vibration Only at 2000 CM-1 in Fully Polycrystalline Silicon Films Made by Hwcvd

2000 ◽  
Vol 609 ◽  
Author(s):  
J.K. Rath ◽  
R.E.I. Schropp
Keyword(s):  
Polycrystalline Silicon ◽  
Vapour Deposition ◽  
Chemical Vapour ◽  
Amorphous Region ◽  
Hot Wire ◽  
Wire Temperature ◽  
Stretching Vibration ◽  
Closed Structure ◽  
Si Films ◽  
Polycrystalline Silicon Films

ABSTRACTThe Si-H vibration in IR spectra of our device quality poly-Si films grown by hot-wire chemical vapour deposition (HWCVD) made at low wire temperature (Tw=1800 °C) is at 2000 cm−1 whereas in a poly-Si film made at high wire temperature (Tw=1900 °C) both 2000 cm−1 vibrations as well as 2100 cm−1 are observed. On the other hand, the Raman spectra (probing the upper part of the film) of Si-H stretching vibration measured for both these samples show only 2000 cm-1 mode. XTEM micrographs of these films show that whereas the low Tw film has a structure made of closely packed crystalline columns, the high Tw film has conical crystalline structures with amorphous region between them. The crystal cones meet each other towards the top of the film and form a closed structure. This is confirmed by Raman spectrum at 520 cm−1. We attribute the 2100 cm−1 mode to the Si-H bonds at the surface of the cones touching the amorphous regions. The Si-H vibration shifts to 2000 cm-1 when the crystalline cones coalesce with each other, as is the case in the upper part of both types of films.

Fast Deposition of Polycrystalline Silicon Films by Hot-Wire CVD

1995 ◽  
Vol 377 ◽  
Author(s):  
A. R. Middya ◽  
A. Lloret ◽  
J. Perrin ◽  
J. Huc ◽  
J. L. Moncel ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Polycrystalline Silicon ◽  
Vapour Deposition ◽  
Chemical Vapour ◽  
Hot Wire ◽  
Crystalline Orientation ◽  
Silicon Thin Films ◽  
Hydrogen Dilution ◽  
Si Films ◽  
Polycrystalline Silicon Films

ABSTRACTPolycrystalline silicon thin films have been deposited at fast growth rates (50 Å/s) by hotwire chemical vapour deposition (HW-CVD) from SiH4/H2 gas mixtures at low substrate temperature (400–500°C). The surface morphology of these films consists of 0.5 – 2.0μm dendritic grains as seen by electron microscopy. The films have a columnar morphology with grains starting from the substrate either on glass or c-Si. Even the 150 nm thick initial layer is polycrystalline. The preferential crystalline orientation of the poly-Si film is apparently not governed by the radiative source but strongly depends on the type and orientation of the substrate. A strong hydrogen dilution (>90%) of silane is essential to obtain poly-Si films with optimal crystalline structure.

Photoconductive Polycrystalline Silicon Films on Glass Obtained by Hot-Wire CVD

1996 ◽  
Vol 420 ◽  
Author(s):  
A. R. Middya ◽  
J. Guillet ◽  
J. Perrin ◽  
J. E. Bouree
Keyword(s):  
Polycrystalline Silicon ◽  
Chemical Vapour ◽  
Columnar Structure ◽  
Silicon Films ◽  
High Deposition Rate ◽  
Hot Wire ◽  
Si Films ◽  
Polycrystalline Silicon Films ◽  
Deposited Films

AbstractTextured polycrystalline silicon films with columnar structure have been deposited on glass at low temperature (400–550°C) and high deposition rate (10 to 15 Å/s) by hot-wire chemical vapour deposition using SiH4-H2 gases. The homogeneity of the deposited layer is ± 5% on a 8 cm diameter. As deposited films have a poor photoconductivity. However hydrogen confinement in the films during the deposition or after the deposition is found to be the key for obtaining g.tc/poly-Si with a significant diffusion length. Eventually reasonable values of the mobility lifetime product (> 10−7 cm2/V) are obtained by in situ hydrogen passivation of poly-Si films after deposition. Efficient shifting of the Fermi level is achieved by in situ B or P doping. The incorporation of boron in poly-Si network strongly influences the morphology and the crystalline structure. Undoped films have a Hall mobility of 14 ± 5 cm2/V.s which decreases versus the carrier concentration.

scholarly journals Polycrystalline silicon films obtained by hot-wire chemical vapour deposition

1994 ◽  
Vol 59 (6) ◽  
pp. 645-651 ◽  
Author(s):  
J. Cifre ◽  
J. Bertomeu ◽  
J. Puigdollers ◽  
M. C. Polo ◽  
J. Andreu ◽  
...  
Keyword(s):  
Chemical Vapour Deposition ◽  
Polycrystalline Silicon ◽  
Vapour Deposition ◽  
Chemical Vapour ◽  
Silicon Films ◽  
Hot Wire ◽  
Polycrystalline Silicon Films

On the Temperature Dependence of Resistivity of Polycrystalline Silicon Films

1987 ◽  
Vol 106 ◽  
Author(s):  
Mark S. Rodder ◽  
Dimitri A. Antoniadis
Keyword(s):  
Numerical Calculation ◽  
Polycrystalline Silicon ◽  
Amorphous Region ◽  
Defect States ◽  
Temperature Dependent ◽  
Step Process ◽  
Dependent Potential ◽  
Si Films ◽  
Polycrystalline Silicon Films ◽  
P Type

ABSTRACTIt is shown that the grain boundary (GB) in polycrystalline-silicon (poly-Si) films need not be modeled as a temperature-dependent potential barrier or as an amorphous region to explain the temperature (T) dependence of resistivity (ρ) in p-type poly-Si films at low T. Specifically, we consider that QB defect states allow for the tunneling component of current to occur by a two-step process. Incorporation of the two-step process in a numerical calculation of ρ vs. T results in excellent agreement with available data from 100 K to 300 K.

scholarly journals p+ polycrystalline silicon growth via hot wire chemical vapour deposition for silicon solar cells

2020 ◽  
Vol 705 ◽  
pp. 137978 ◽  
Author(s):  
Edris Khorani ◽  
Tudor E. Scheul ◽  
Antulio Tarazona ◽  
John Nutter ◽  
Tasmiat Rahman ◽  
...  
Keyword(s):  
Solar Cells ◽  
Chemical Vapour Deposition ◽  
Polycrystalline Silicon ◽  
Vapour Deposition ◽  
Chemical Vapour ◽  
Silicon Solar Cells ◽  
Hot Wire ◽  
Silicon Growth
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