Reactivity and Migration of Hydrogen in A-SI:H

1997 ◽  
Vol 467 ◽  
Author(s):  
R. Biswas ◽  
Qiming Li ◽  
B. C. Pan ◽  
Y. Yoon
Keyword(s):  
Molecular Dynamics ◽  
Amorphous Silicon ◽  
Hydrogen Diffusion ◽  
Tight Binding ◽  
Hydrogenated Amorphous Silicon ◽  
Dangling Bond ◽  
Molecular Dynamics Calculations ◽  
And Migration ◽  
Hydrogenated Amorphous

ABSTRACTTight-binding molecular dynamics calculations reveal a new mechanism for hydrogen diffusion in hydrogenated amorphous silicon. Hydrogen diffuses through the network by successively bonding with nearby silicon and breaking their Si-Si bonds. The diffusing hydrogen carries with it a newly created dangling bond. These intermediate transporting states are densely populated in the network and have lower energies than H at the center of stretched Si-Si bonds.

Computer-Generated Structural Models for a-Si:H

1988 ◽  
Vol 141 ◽  
Author(s):  
Laurent J. Lewis ◽  
Normand Mousseau ◽  
FranÇois Drolet
Keyword(s):  
Molecular Dynamics ◽  
Boundary Conditions ◽  
Amorphous Silicon ◽  
Periodic Boundary ◽  
Hydrogenated Amorphous Silicon ◽  
Structural Models ◽  
Periodic Boundary Conditions ◽  
Dynamics Simulations ◽  
Hydrogenated Amorphous ◽  
Good Agreement

AbstractA new algorithm for generating fully-coordinated hydrogenated amorphous silicon models with periodic boundary conditions is presented. The hydrogen is incorporated into an a-Si matrix by a bond-switching process similar to that proposed by Wooten, Winer, and Weaire, making sure that four-fold coordination is preserved and that no rings with less than 5 members are created. After each addition of hydrogen, the structure is fully relaxed. The models so obtained, to be used as input to molecular dynamics simulations, are found to be in good agreement with experiment. A model with 12 at.% H is discussed in detail.

Doping Mechanism in Tetrahedral Amorphous Carbon

1997 ◽  
Vol 498 ◽  
Author(s):  
C W Chen ◽  
J Robertson
Keyword(s):  
Amorphous Silicon ◽  
Amorphous Carbon ◽  
Hydrogenated Amorphous Silicon ◽  
Donor Atom ◽  
Dangling Bond ◽  
Coulombic Repulsion ◽  
Tetrahedral Amorphous Carbon ◽  
Total Energies ◽  
Doping Mechanism ◽  
Hydrogenated Amorphous

ABSTRACTDoping in hydrogenated amorphous silicon occurs by a process of an ionised donor atom partially compensated by a charged dangling bond. The total energies of various dopant and dopant/bonding combinations are calculated for tetrahedral amorphous carbon. It is found that charged dangling bonds are less favoured because of the stronger Coulombic repulsion in ta-C. Instead the dopants can be compensated by weak bond states in the lower gap associated with odd-membered π-rings or odd-numbered π-chains. The effect is that the doping efficiency is low but there are not charged midgap recombination centres, to reduce photoconductivity or photoluminescence with doping, as occurs in a-Si:H.

Role of Hydrogen Microstructure in Amorphous Silicon

1992 ◽  
Vol 258 ◽  
Author(s):  
Sufi Zafar ◽  
E. A. Schiff
Keyword(s):  
Amorphous Silicon ◽  
Hydrogen Evolution ◽  
Hydrogen Diffusion ◽  
Hydrogenated Amorphous Silicon ◽  
Hydrogenated Amorphous ◽  
Unified Description

ABSTRACTA model for correlating the observed properties of hydrogenated amorphous silicon (a-Si:H) with the underlying hydrogen microstructure is reviewed. The model provides a unified description of defect equilibration, hydrogen evolution, rehydrogenation and hydrogen diffusion measurements.

Observation of slow dangling-bond relaxation inp-type hydrogenated amorphous silicon

1995 ◽  
Vol 51 (4) ◽  
pp. 2173-2179 ◽  
Author(s):  
Martin W. Carlen ◽  
Yueqin Xu ◽  
Richard S. Crandall
Keyword(s):  
Amorphous Silicon ◽  
Hydrogenated Amorphous Silicon ◽  
Dangling Bond ◽  
Hydrogenated Amorphous
Sign in / Sign up

Export Citation Format

Share Document