Microstructure Evolution in He-Implanted Si at 600 °C Followed by 1000 °C Annealing

Si single crystal was implanted with 230 keV He+ ions to a fluence of 5 x 10(16)/cm(2) at 600 degrees C. The structural defects in Si implanted with He at 600 degrees C and then annealed at 1000 degrees C were investigated by transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). The microstructure of an as-implanted sample is provided for comparison. After annealing, rod-like defects were diminished, while tangled dislocations and large dislocation loops appeared. Dislocation lines trapped by cavities were directly observed. The cavities remained stable except for a transition of shape, from octahedron to tetrakaidecahedron. Stacking-fault tetrahedrons were found simultaneously. Cavity growth was independent of dislocations. The evolution of observed lattice defects is discussed.

Automated summary

In this study, structural defects in silicon implanted with helium ions at 600 degrees C and then annealed at 1000 degrees C were investigated using transmission electron microscopy. After annealing, rod-like defects decreased while tangled dislocations and large dislocation loops appeared. The shape of cavities transitioned from octahedron to tetrakaidecahedron, and stacking-fault tetrahedrons were found.