Silicon Powder-Based Wafers for Low-Cost Photovoltaics: Laser Treatments and Nanowire Etching

Figure 1

(a) Photograph of the samples irradiated by the laser at 15.0 (upper case) and 13.5 kW cm⁻² (lower case) at a scan speed of 10 mm s⁻¹; (b) SEM image (70° tiled) at the cross section with a rough surface of the nonirradiated region and the smooth laser-recrystallized region; (c) surface morphology of the laser-recrystallized region showing examples of protrusions and microvoids on the surface; (d) a crack induced by the laser recrystallization process and microvoid in the volume; (e) top-view EBSD image of the as-cut pc-Si sample; (f) top-view EBSD image of the laser-recrystallized (at a power density of 13.5 kW cm⁻²) pc-Si sample.

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