Effect of Post Metallization Annealing for La 2 O 3 Thin Film

1.2 Rare Earth Oxides as the Candidates of High-k Dielectricsand Their PropertiesIn order to overcome the limits of SiO2 explained in previous section,several promising materials have been investigated in recent years by alarge number of researchers. The elements which can be the candidates ofthe alternative insulator are quite limited because of the reaction failurewith Silicon or radioactivity as shown in Figure 1-5. Under these restrictedconditions, metal oxides (MOx) like Al2O3, ZrO , HfO2 and recently N, Si, orAl doped HfO2 gate dielectrics such as HfSiON, HfAlx, HfON and rare earthoxides have been studied eagerly for the next generation gate dielectricmaterials.Figure 1-5: Candidates of the elements which have possibility to be utilizedas high-k gate insulators-8 -