Passivating antireflection coating of crystalline silicon using i/n a-Si:H/SiN trilayer

Passivating antireflection coating of crystalline silicon has been experimentally studied using a three-layered stack, consisting of an i/n a-Si:H/SiN trilayer. The passivation property is characterized by the minority carrier lifetime, which shows ≳ 1 ms for the i/n a-Si:H/SiN trilayer prepared at a temperature as low as 250 ∘C. The antireflection property is confirmed by a reflection of light of ≲ 2.0% at 550 nm and a low reflection in a wide range of visible and near-infrared regions, which is adequate for solar cell application, particularly in back-contact structure. The roles of each layer are discussed in terms of the chemical and field-effect passivation as well as the antireflection property. The optoelectronic properties of a neat SiN layer are also discussed to achieve a stable and reliable antireflection performance under the low-temperature growth conditions.