Single crystalline Pr2-xYxO3 (x=0-2) dielectrics on Si with tailored electronic and crystallographic structure

Crystalline oxides on Si with tailored electronic and crystallographic properties are of importance for the integration of functional oxides or alternative semiconductors to enable novel device concepts in Si microelectronics. We present an electronic band gap study of single crystalline Pr2-xYxO3 (0≤x≤2) heterostructures on Si(111). The perfect solubility of the isomorphic bixbyites Pr2O3 and Y2O3 during molecular beam epitaxy thin film growth on Si enables a linear band gap tuning. Special focus is devoted to the determination of the electronic band offsets across the dielectric/Si interface. In addition, the composition x allows to control the crystallographic lattice parameter where, for example, Pr0.8Y1.2O3 enables the growth of fully lattice matched oxide heterostructures on Si.