Periodic dimple lines on the surface of the grain-boundary free (100) Si thin films grown by the continuous-wave laser crystallization

Periodic dimple lines have been found by the atomic-force-microscopy on the surface of the grain-boundary free (100) Si films obtained by the continuous-wave laser crystallization. The dimple lines are straight and run parallel each other to the scan direction regularly at a period of ∼3.1 μm. The depth of the dimple lines is 3∼5 nm (peak-to-valley). The internal angle of the dimple lines is ∼179.4°. These dimple lines originate from hyperfine sub-boundaries with a boundary energy of 2.4 × 10⁻⁶ J/cm², a rotation angle θ of ∼0.061°, and a dislocation spacing of ∼0.36 μm.