Reduction of surface recombination velocity by rapid thermal annealing of p-Si passivated by catalytic-chemical vapor deposited alumina films

•Excellent passivation of p-Si in Si solar cells has been archived by rapid annealing of Al2O3 films prepared by Cat-CVD.•Extremely small surface recombination velocity (S0) below 0.1 cm/s has been obtained at Al2O3 films post annealed.•The extremely small S0 has been obtained by post-deposition rapid thermal annealing temperature of 350oC-400oC for 2 min.•The reduction of S0 has been attributed to band bending induced by fixed negative charge density of 5x1011 charges/cm2.

Excellent electrical-passivation of p-type Si (p-Si) in Si solar cells has been achieved by post-deposition rapid annealing of aluminum oxide (AlOx) films prepared by catalytic chemical vapor deposition (Cat-CVD) using trimethyl aluminum (TMA) and O2. Extremely small surface recombination velocity of below 0.1 cm/s has been obtained at post-deposition annealing temperatures in the range of 350–400 °C for an annealing time of 2 min. The reduction of surface recombination velocity has been attributed to band bending induced by a fixed negative charge density of 5 × 1011 charges/cm2 and an additional small interface trapping density of around 1010 cm− 2 eV− 1.