Controlled orientation of molecular-beam-epitaxial BaTiO₃on Si(001) using thickness engineering of BaTiO₃and SrTiO₃buffer layers

Monolithically integrating BaTiO 3 on silicon substrates has attracted attention because of the wide spectrum of potential novel applications ranging from electronics to photonics. For optimal device performance, it is important to control the BaTiO 3 domain orientation during thin film preparation. Here, we use molecular beam epitaxy to prepare crystalline BaTiO 3 on Si(001) substrates using a SrTiO 3 buffer layer. A systematic investigation is performed to understand how to control the BaTiO 3 domain orientation through the thickness engineering of the SrTiO 3 buffer layer and the BaTiO 3 layer itself. This provides different possibilities for obtaining a given BaTiO 3 orientation as desired for a specific device application.