Equilibration in Amorphous Silicon Nitride Alloys

ABSTRACTSeveral series of amorphous silicon nitride thin films have been grown by plasma-enhanced chemical vapour deposition, where the ratio of ammonia and silane feed gases was held constant for each series while the deposition temperature was varied from 160 °C to 550 °C, and all other deposition conditions were held constant. Photothermal Deflection Spectroscopy measurements were used to determine the Urbach slope E0 and the defect density ND. It is found that ND is determined by E0 for most of these samples, suggesting that defect equilibration occurs in a-SiNx:H for x up to at least 0.6. The growth temperature at which the disorder is minimised increases to higher values with increasing x, which is explained in terms of a hydrogen-mediated bond equilibration reaction. Fourier Transform Infra Red spectroscopy measurements were performed to determine the changes in hydrogen bonding with growth temperature. The results suggest that a second bond equilibration reaction also occurs at the growing surface, but that equilibrium cannot be reached at higher temperatures because of hydrogen evolution from Si-H bonds.

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Plasma-enhanced chemical vapour deposition of amorphous silicon nitride for thin film diode active matrix liquid crystal displays

Thin Solid Films ◽

10.1016/0040-6090(94)90443-x ◽

1994 ◽

Vol 241 (1-2) ◽

pp. 287-290 ◽

Cited By ~ 11

Author(s):

G. Oversluizen ◽

W.H.M. Lodders ◽

I.D. French

Keyword(s):

Thin Film ◽

Liquid Crystal ◽

Silicon Nitride ◽

Amorphous Silicon ◽

Vapour Deposition ◽

Chemical Vapour ◽

Liquid Crystal Displays ◽

Active Matrix ◽

Amorphous Silicon Nitride ◽

Matrix Liquid

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Deposition of amorphous silicon nitride thin films by CO2 laser-induced chemical vapour deposition

Journal of Non-Crystalline Solids ◽

10.1016/0022-3093(95)00163-8 ◽

1995 ◽

Vol 187 ◽

pp. 353-360 ◽

Cited By ~ 4

Author(s):

J. Serra ◽

T. Szörényi ◽

D. Fernández ◽

P. González ◽

E. García ◽

...

Keyword(s):

Thin Films ◽

Silicon Nitride ◽

Amorphous Silicon ◽

Chemical Vapour Deposition ◽

Co2 Laser ◽

Vapour Deposition ◽

Chemical Vapour ◽

Amorphous Silicon Nitride

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Electronic Properties of Microcrystalline Silicon

MRS Proceedings ◽

10.1557/proc-467-283 ◽

1997 ◽

Vol 467 ◽

Cited By ~ 36

Author(s):

R. Carius ◽

F. Finger ◽

U. Backhausen ◽

M. Luysberg ◽

P. Hapke ◽

...

Keyword(s):

Vapour Deposition ◽

Volume Fraction ◽

Crystalline Silicon ◽

Chemical Vapour ◽

Structural Defects ◽

Photoluminescence Properties ◽

Crystalline Volume Fraction ◽

Microcrystalline Silicon ◽

Photothermal Deflection Spectroscopy ◽

Photothermal Deflection

ABSTRACTThe electronic and optical properties of microcrys tall ine silicon films prepared by plasma enhanced chemical vapour deposition are investigated with Hall-effect, electrical conductivity, photothermal deflection spectroscopy and photoluminescence measurements. In particular, the influence of the grain size and the crystalline volume fraction on the conductivity, the carrier density and the Hall mobility is investigated in highly doped films. A percolation model is proposed to describe the observed transport data. Photoluminescence properties were studied in un-doped films. It is proposed that the photoluminescence is due to recombination at structural defects similar to those observed in crystalline silicon.

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Investigation of 3C-SiC(111) Homoepitaxial Growth by CVD at High Temperature

Materials Science Forum ◽

10.4028/www.scientific.net/msf.645-648.127 ◽

2010 ◽

Vol 645-648 ◽

pp. 127-130 ◽

Cited By ~ 6

Author(s):

Nikoletta Jegenyes ◽

Jean Lorenzzi ◽

Véronique Soulière ◽

Jacques Dazord ◽

François Cauwet ◽

...

Keyword(s):

High Temperature ◽

Surface Morphology ◽

Gas Phase ◽

Chemical Vapour Deposition ◽

Growth Temperature ◽

Vapour Deposition ◽

Defect Density ◽

Chemical Vapour ◽

Defect Size ◽

Homoepitaxial Growth

Starting from 3C-SiC(111) layers grown by Vapour-Liquid-Solid mechanism, homoepitaxial growth by Chemical Vapour Deposition was carried out on top of these seeds. The effect of the growth temperature and of the C/Si ratio in the gas phase was investigated on the surface morphology, the roughness and the defect density. It was found that the initial highly step-bunched surface of the VLS seeds could be greatly smoothen using appropriate conditions. These conditions were also found to reduce significantly the defect size and/or density at the surface.

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Raman and FTIR Studies on PECVD Grown Ammonia-Free Amorphous Silicon Nitride Thin Films for Solar Cell Applications

Conference Papers in Energy ◽

10.1155/2013/837676 ◽

2013 ◽

Vol 2013 ◽

pp. 1-4 ◽

Cited By ~ 3

Author(s):

Nafis Ahmed ◽

Chandra Bhal Singh ◽

S. Bhattacharya ◽

S. Dhara ◽

P. Balaji Bhargav

Keyword(s):

Thin Films ◽

Silicon Nitride ◽

Amorphous Silicon ◽

Flow Rate ◽

Chemical Vapour ◽

Nitrogen Flow ◽

Raman Analysis ◽

Amorphous Silicon Nitride ◽

Vis Spectroscopy ◽

Hydrogenated Amorphous

Ammonia- (NH3-) free, hydrogenated amorphous silicon nitride (a-SiNx:H) thin films have been deposited using silane (SiH4) and nitrogen (N2) as source gases by plasma-enhanced chemical vapour deposition (PECVD). During the experiment, SiH4 flow rate has been kept constant at 5 sccm, whereas N2 flow rate has been varied from 2000 to 1600 sccm. The effect of nitrogen flow on SiNx:H films has been verified using Raman analysis studies. Fourier transform Infrared spectroscopy analysis has been carried out to identify all the possible modes of vibrations such as Si–N, Si–H, and N–H present in the films, and the effect of nitrogen flow on these parameters is correlated. The refractive index of the above-mentioned films has been calculated using UV-VIS spectroscopy measurements by Swanepoel’s method.

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Method for the Reduction of Photothermal Deflection Spectroscopy Data Taken on Amorphous Silicon (a-Si:H)

MRS Proceedings ◽

10.1557/proc-95-145 ◽

1987 ◽

Vol 95 ◽

Cited By ~ 10

Author(s):

S. Wiedeman ◽

M. S. Bennett ◽

J. L. Newton

Keyword(s):

Optical Absorption ◽

Amorphous Silicon ◽

Fourier Transformation ◽

Spectroscopy Data ◽

Interference Effects ◽

Optical Interference ◽

Photothermal Deflection Spectroscopy ◽

Photothermal Deflection ◽

Sensitive Method ◽

Deposition Conditions

AbstractPhotothermal deflection spectroscopy (PDS) is a sensitive method used to measure weak optical absorption of sub-bandgap radiation. A method utilizing Fourier transformation is presented which allows removal of optical interference effects and noise which is typically present in PDS data taken on a-Si:H, yet leaves the underlying PDS spectra undistorted. The method greatly facilitates comparison of PDS spectra taken on different samples, and simplifies further analysis. Examples using a-Si samples produced under different deposition conditions are presented to demonstrate the utility of the method.

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Optimization of 75°C amorphous silicon nitride for TFTs on plastics

MRS Proceedings ◽

10.1557/proc-769-h9.8 ◽

2003 ◽

Vol 769 ◽

Cited By ~ 8

Author(s):

Christian McArthur ◽

Mark Meitine ◽

Andrei Sazonov

Keyword(s):

Silicon Nitride ◽

Amorphous Silicon ◽

Compressive Stress ◽

Gas Flow ◽

Gate Dielectric ◽

Large Area ◽

Film Properties ◽

Amorphous Silicon Nitride ◽

Electrical Stress ◽

Deposition Conditions

AbstractAmorphous silicon nitride (a-SiNx) is widely used as the gate dielectric and passivation layer in a-Si:H based electronics. For devices on plastic substrates deposited at low temperature, the a-SiNx quality seems to determine the device performance. This paper investigates the effects of hydrogen dilution, helium dilution, ammonia-silane gas flow ratio, and RF power on the properties of PECVD silicon nitrides deposited in large-area parallel-plate reactors at substrate temperatures of 75°C. The chemical composition and bonding of the SiNx:H films was studied using FTIR spectroscopy. The physical properties were investigated, and the density, growth rate, and compressive stress of the films were determined. The electrical properties such as leakage current, breakdown, stability, trap density, and dielectric constant of the films were characterized by I-V and C-V measurements of metal-insulator semiconductor (MIS) structures. Analysis of Variance (ANOVA) was performed on the results, and the deposition conditions for the optimal film properties were determined. The optimum film had SiNx:H stoichiometry of x=1.56 with hydrogen concentrations of 17 at.%, and exhibited compressive stress of -220 MPa. The film displayed good stability under electrical stress with ohmic leakage of Rleak ∼1016 Ωcm. Strong relationships between the film properties and deposition conditions were observed, and are discussed within the paper. A-Si:H bottom gate TFTs were fabricated using the optimized nitrides for gate dielectrics and passivation layers, and the influence of a-SiNx on TFT performance is discussed.

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