Passivation of HfO2/Ge interface with YON fabricated by different approaches

Nitrided Y2O3 (YON) interfacial passivation layer (IPL) is used to passivate the HfO2/Ge interface for better interfacial and electrical properties of Ge metal-oxide-semiconductor (MOS) capacitor. Two different approaches were used to prepare the YON IPL, one is to deposit YON directly by sputtering Y2O3 target in Ar+N2 ambient, and the other is to deposit YN first by sputtering Y target in Ar+N2 ambient followed by the annealing in N2+O2 to convert YN to YON. Experimental results indicate that the MOS capacitor fabricated by the latter approach could achieve more excellent interfacial and electrical properties due to more effective suppression of the formation of Ge oxides