Improved Silicon Surface Passivation by ALD Al ₂ O ₃ /SiO ₂ Multilayers with In‐Situ Plasma Treatments

Al2O3 is one of the most effective dielectric surface passivation layers for silicon solar cells, but recent studies indicate that there still room improvement. Instead a single layer, multilayers only few nanometers thickness offer possibility to tailor material properties on nanometer scale. In this study, effect various plasma treatments performed at different stages during ALD deposition Al2O3/SiO2 quality evaluated. Significant improvements in some are observed, particularly bilayers treated with H2 after SiO2 deposition. This treatment resulted recombination parameter J0 as low 0.35 fA cm−2 (100) surfaces 10 Ω cm n-type silicon, more than factor 5 lower without treatment. Capacitance-voltage measurements improved plasma-treated samples results from an enhanced chemical interface rather field effect. addition, superior temperature stability found multilayers.