Plasma-free Dry-chemical Texturing Process for High-efficiency Multicrystalline Silicon Solar Cells

In this paper, we study the influence of modifying the geometry of nanotexture on its electrical properties. Nanotexture is formed by an industrially feasible dry-chemical etching process performed entirely in atmospheric pressure conditions. A surface modification process is developed that allows low surface recombination velocities (Seff,min ≤ 10 cm/s) on nanotextured surfaces. By simultaneously improving the surface passivation and the emitter diffusion processes, we achieve an equivalent passivation level (VOC,impl ≥ 670 mV) for nanotextured surfaces to that of reference textured surfaces after applying either PECVD or ALD based deposition techniques.