Data for Electronic characteristics of ultra-thin passivation layers for silicon photovoltaics

Certain dielectric coatings of more than 10 nm provide excellent surface passivation, and ultra-thin (<2 nm) dielectric layers can serve as interlayers in passivating contacts. Here, ultra-thin passivating films of SiO2, Al2O3, and HfO2 are created via plasma-enhanced atomic layer deposition and annealing.

It is found that thin negatively charged HfO2 layers exhibit excellent passivation properties—exceeding those of SiO2 and Al2O3—with 0.9 nm HfO2 annealed at 450 °C providing a surface recombination velocity of 18.6 cm s−1. The passivation quality is dependent on annealing temperature and layer thickness, and optimum passivation is achieved with HfO2 layers annealed at 450 °C measured to be 2.2–3.3 nm thick which give surface recombination velocities ≤2.5 cm s−1 and J0 values of ≈14 fA cm−2.