First-principles modeling of high-k gate dielectric materials

Materials problems of alternative high-k dielectric oxides for future metal–oxide–semiconductor field effect transistor (MOSFET) gate oxide application are examined from first-principles modeling perspective. We have analyzed the relationship between local atomic structures and the corresponding ionic contributions to static dielectric constant for metal oxides, and the analysis shows the importance of stabilizing high oxygen coordination structures for metal atoms. Based on the local atomic structure analysis, metal silicates and aluminate are expected to provide a possible solution of continuously scaling dielectric constant well above the values of amorphous silica (ε0=3.9) and alumina (ε0=9).