A combinatorial approach in oxide/semiconductor interface research for future electronic devices

A combinatorial methodology was employed to investigate oxide/semiconductor interfaces for future devices using a combination of temperature gradient pulsed laser deposition and transmission electron microscopy. In growing oxide materials on Si substrate, a proper termination was found to be inevitable for avoiding surface oxidation. For this purpose, arsenic was used to obtain a durable surface of Si in oxygen atmosphere. On this surface, CeO2 and SrTiO3 were grown to study interface stability and phenomena. CeO2 and SrTiO3 were found to have abrupt structures at 200 °C. At a higher temperature at 550 °C, an amorphous interfacial layer was formed for the SrTiO3/Si interface. From the results, surface termination and the growth temperature were identified as factors governing the process of abrupt interface formation.