High efficiency interdigitated back-contact c-Si(p) solar cells

In this work we describe a baseline fabrication process of interdigitated-back-contact c-Si(p) solar cells, which combines conventional diffusion oven stages to define base p+ and emitter n+ regions at the backside, with front surface passivation using atomic layer deposited Al
₂
O
₃
films on textured surfaces with random pyramids. Very low reflectance with outstanding surface recombination velocity values around 3 cm/s are achieved in our precursors. Fabricated solar cells reach efficiencies up to 20.3% (AM1.5G 1 kW/m
²
, T=25°C), with short circuit density J
_sc
, open circuit voltage V
_oc
and fill factor FF of 40.6 mA/cm
²
, 648 mV and 77.2% respectively.