Comparative Study of Structure and Hydrogen Incorporation in Glow Discharge a-Si:C:H and a-Si:N:H Alloys

1987 ◽  
Vol 95 ◽  
Author(s):  
W. Beyer ◽  
H. Wagner ◽  
H. Mell
Keyword(s):  
Glow Discharge ◽  
Comparative Study ◽  
Substrate Temperature ◽  
Nitrogen Content ◽  
Hydrogen Evolution ◽  
Hydrogen Concentration ◽  
Infrared Absorption ◽  
Hydrogen Incorporation ◽  
Nitrogen Incorporation ◽  
Void Structure

AbstractPlasma-deposited a-Si:C:H and a-Si:N:H alloys both show a rapidly rising hydrogen incorporation with increasing carbon or nitrogen content. For hydrogen concentrations exceeding ∼ 20 at.%, the host material starts to lose its connectiveness leading to the formation of a void structure as evidenced by hydrogen evolution and infrared absorption. Raising the substrate temperature leads to a reduction of the hydrogen concentration, to an increase of the Si-C and Si-N bond concentration and to a more compact naterial. However, for a-Si:C:H films it leads also to graphitic carbon bonds. The widening of the optical bandgap of a-Si:C:H films up to about 50 at.% of carbon is almost entirely due to the increased hydrogen incorporation whereas for a-Si:N:H films both hydrogen and nitrogen incorporation plays a role.

Hydrogen Incorporation in A-Si:H: Temperature and Doping Type Dependence

1990 ◽  
Vol 192 ◽  
Author(s):  
M.J.M. Pruppers ◽  
K.M.H. Maessen ◽  
F.H.P.M. Habraken ◽  
J. Bezemer ◽  
W.F. Van Der Weg
Keyword(s):  
Activation Energy ◽  
Glow Discharge ◽  
Gas Phase ◽  
Hydrogen Concentration ◽  
Hydrogen Content ◽  
Hydrogen Incorporation ◽  
Undoped Material ◽  
Measured Activation Energy ◽  
Measured Activation ◽  
The Difference

ABSTRACTPhosphorus, boron and compensation doped hydrogenated amorphous silicon films were deposited in a glow discharge at different substrate temperatures in the range 50–330°C. Gas phase doping levels were 1%. At the lower temperatures the hydrogen concentration in the B doped and compensated doped films is larger than in the P and undoped films. For higher deposition temperatures the H concentration of the B doped films appeared to be smaller than in the other materials. The difference in hydrogen content of the doped and undoped material, deposited at various temperatures, is considered as a function of the measured activation energy for conduction in these films. This difference varies in much the same way with the activation energy as the hydrogen content in films deposited at one substrate temperature, but with varying gas phase dopant levels. This represents strong evidence that, apart from the deposition temperature, the hydrogen concentration in glow discharge a-Si:H is determined by the position of the Fermi level.

Comparative study on nonlinear dynamics of magnetized and un-magnetized dc glow discharge plasma

2013 ◽  
Vol 88 (6) ◽  
pp. 065005 ◽  
Author(s):  
Bornali Sarma ◽  
Sourabh S Chauhan ◽  
A M Wharton ◽  
A N Sekar Iyengar
Keyword(s):  
Nonlinear Dynamics ◽  
Glow Discharge ◽  
Comparative Study ◽  
Discharge Plasma ◽  
Glow Discharge Plasma ◽  
Dc Glow Discharge

Methods of Improving Glow-Discharge-Deposited a-Si1−xGex:H

1991 ◽  
Vol 219 ◽  
Author(s):  
Y. S. Tsuo ◽  
Y. Xu ◽  
E. A. Ramsay ◽  
R. S. Crandall ◽  
S. J. Salomon ◽  
...  
Keyword(s):  
Material Processing ◽  
Glow Discharge ◽  
Substrate Temperature ◽  
Gas Mixtures ◽  
Gas Composition ◽  
Processing Methods ◽  
Helium 4 ◽  
Process Gas

ABSTRACTWe have studied methods of improving glow-discharge-deposited a-Si1−x Gex :H alloys deposited using silane and germane gas mixtures. Material processing methods studied include (1) varying the substrate temperature from 170° to 280°C, (2) varying the process gas composition and pressure, (3) dilution of the feed gas by hydrogen, argon, or helium, (4) enhancing etching during deposition by adding small amounts of XeF2 vapor into the process gas, and (5) postdeposition annealing and/or hydrogenation.

Absorption Strengths of Si-H Vibrational Modes in Hydrogenated Silicon

1998 ◽  
Vol 507 ◽  
Author(s):  
W. Beyer ◽  
M.S. Abo Ghazala
Keyword(s):  
Refractive Index ◽  
Hydrogen Concentration ◽  
Infrared Absorption ◽  
Molecular Hydrogen ◽  
Vibrational Modes ◽  
Absorption Data ◽  
Hydrogenated Silicon ◽  
Hydrogen Density ◽  
The Absolute ◽  
Hydrogen Effusion

ABSTRACTInfrared absorption data of various Si:H samples involving several series of a-Si:H films as well as µc-Si:H and c-Si:H samples were analyzed to obtain ratios of the absorption strengths A of the Si-H stretching modes at 2000 and 2100 cm−1 and of the Si-H wagging mode at 640 cm−1. Hydrogen effusion measurements were used to obtain the absolute values of A. The results suggest essentially equal absorption strengths for the two Si-H stretching modes and a ratio of wagging and stretching absorption strengths independent of hydrogen density NH. Films with predominant 2100 cm−1stretching absorption show a stronger sample dependence of A than observed for samples with predominant 2000 cm−1absorption. A slight increase of the absorption strength of the Si-H wagging and stretching modes with rising hydrogen concentration is observed for a-Si:H films and is attributed to the decrease of the refractive index. Enhanced A values of µc-Si:H samples compared to a-Si:H samples point to the presence of molecular hydrogen.

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