TY  - EJOU
AU  - Liu, W. C. 
AU  - Shi, S. Q.  
AU  - Woo, C. H.  
AU  - Huang, Hanchen  

TI  - Dislocation Nucleation and Propagation During Thin Film Deposition Under Tension
T2  - Computer Modeling in Engineering \& Sciences

PY  - 2002
VL  - 3
IS  - 2
SN  - 1526-1506

AB  - Using molecular dynamics method, we study the nucleation of dislocations and their subsequent propagation during the deposition of tungsten thin films under tension. Aiming to reveal the generic mechanisms of dislocation nucleation during the deposition of polycrystalline thin films, the case of tungsten on a substrate of the same material is considered. The substrate is under uniaxial tension along the [111] direction, with the thermodynamically favored  (01<sup style="margin-left:-6px">ˉˉ</sup>1) surface being horizontal. The simulation results indicate that the nucleation starts with a surface step, where a surface atom is pressed into the film along the [111<sup style="margin-left:-6px">ˉˉ</sup>] direction. This process leads to the generation of a half dislocation loop of Burgers vector 1/2[111<sup style="margin-left:-6px">ˉˉ</sup>] along the (112) plane, which is about 73° from the horizontal plane. The dislocation propagates along the [3<sup style="margin-left:-6px">ˉˉ</sup>11] direction. As a result of the dislocation nucleation, a sharp surface step is eliminated.
KW  - dislocation nucleation
KW  -  dislocation propagation
KW  -  thin films
KW  -  and molecular dynamics

DO  - 10.3970/cmes.2002.003.213