Crystalline Oxides on Silicon: The First Five Monolayers

The long-standing problem of growing a commensurate crystalline oxide interface with silicon has been solved. Alkaline earth and perovskite oxides can be grown in perfect registry on the (001) face of silicon, totally avoiding the amorphous silica phase that ordinarily forms when silicon is exposed to an oxygen containing environment. The physics of the heteroepitaxy lies in establishing a sequenced transition that uniquely addresses the thermodynamics of a layer-by-layer energy minimization at the interface. A metal-oxide-semiconductor capacitor using $\mathrm{SrTiO}{}_3$ as an alternative to $\mathrm{SiO}{}_2$ yields the extraordinary result of $t_{\mathrm{eq}}<10\mathrm{}Å$.