Q.: Describe the strain energy field of a sixty degree dislocation
in silicon.
adesh.zip
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Answer
ADESH produced following results in a few minutes (on a PC with a 486
micro-processor).
Figure 1
(a) Figure 1 shows the atomisitc configuration
of a sixty degree dislocation in Silicon
(1/2 <110>{111} | <110>).
The Burger's vector is 1/2<110>. The dislocation is along
<110> type direction. The dislocation line and the Burger's vector
lie in {111} type plane.
The dislocation line is perpendicular to the plane of the screen.
At the center of the cell is the core of the sixty degree dislocation.
It consists of an eight atom ring. Figure 2 shows enlarged
portion of the core.
The color changes for the atoms indicate relative increases
in energy for each atom. The chart on the right shows the
respective increase in energy/atom indicated by each color.
Figure 2
Enlarged view of the core of the sixty degree dislocation in
Figure 1. The energy increase/atom is scaled up for a detailed
understanding of the energetics of the core configuration.
Strain field of the sixty degree dislocation
has a slightly oblong shape as seen in Figure 1.
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