Surface Passivation of Silicon Substrate by Ternary GaxCeyOz Layers Grown via Combination of Forming Gas and Oxygen at Different Temperatures

A systematic evaluation of deploying GaxCeyOz passivation layer (PL) on Si substrate subjected to postdeposition annealing in forming gas-oxygen-forming gas ambient at different temperatures (600 to 900oC) was carried out. The inclusion of hydrogen and/or nitrogen ions, in addition to their attachment to oxygen vacancies and Si dangling bonds, has been reported. The attachment became more prominent at 600 and 700oC while oppositely, the incoming oxygen ions acquired adequate energy to break the attachment at/beyond 800oC. Therefore, it is conceivable that the GaxCeyOz PL annealed at/beyond 800oC have attained a thicker interfacial layer (IL). The acquisition of a higher Nss has been attributed to the de-passivation of Si dangling bonds by the excessive hydrogen ions present at the interface. The potential of utilizing GaxCeyOz PL annealed at 700oC as a PL for metal-oxide-semiconductor applications was inferred through a thorough electrical analysis conducted in this work.