Epitaxial perovskite thin films grown on silicon by molecular beam epitaxy

Abstract

Thin film perovskite-type oxide SrTiO3 has been grown epitaxially on Si(001) substrate by molecular beam epitaxy. Reflection high energy electron diffraction and x-ray diffraction analysis indicate high quality SrTiO3 heteroepitaxy on Si substrate with SrTiO3(001)//Si(001) and SrTiO3[010]//Si[110]. The SrTiO3 surface is atomically as smooth as the starting substrate surface, with a root mean square roughness of 1.2 Å observed by atomic force microscopy. The thickness of the amorphous interfacial layer between SrTiO3 and Si has been engineered to minimize the device short channel effect. An effective oxide thickness <10 Å has been obtained for a 110 Å thick dielectric film. The interface state density between SrTiO3 and Si is 6.4×1010 cm−2 eV−1, and the inversion layer carrier mobilities are 221 and 62 cm2 V−1 s−1 for n- and p-channel metal–oxide–semiconductor devices with 1.2 μm effective channel length, respectively. The gate leakage in these devices is two orders of magnitude smaller than a comparable SiO2 gate dielectric metal–oxide–semiconductor field effect transistors.

A silicon-based photocathode for water reduction with an epitaxial SrTiO3 protection layer and a nanostructured catalyst

“…This was used to grow crystalline STO directly on Si(001) using a variant of the Motorola-developed process 42 . The as-received Si(001) wafers were cut to 20 × 20 mm 2 , then cleaned ultrasonically with acetone, isopropyl alcohol and deionized (DI) water for ten minutes each, followed by ultraviolet/ozone exposure for 15 minutes to remove residual carbon contamination.…”

“…Single-crystal STO is grown on Si(001) by molecular beam epitaxy (MBE) using a variant of the Motorola-developed process 42 . More detailed information of the growth is given in the Methods section.…”

Ferromagnetic properties of epitaxial manganite films on SrTiO3∕Si heterostructures

“…However, integrating the manganites onto the semiconducting materials, such as on Si, remains a challenging task for potential device applications that utilize both information processing and data storage in the same device. The recent progresses on direct integration 21,22 of STO on Si have opened a possibility to integrate both STO and R 1−x B x MnO 3 onto this technologically important semiconductor. On the other hand, it is necessary to grow thinner films of manganites on Si using single ultrathin ͑ഛ20 nm͒ template layer for actual technological applications.…”

Effect of Sr adsorption on stability of and epitaxial SrTiO3 growth on Si(001) surface

“…Using the Sr/Si(001)-(2 × 1) as the starting surface, epitaxial SrTiO 3 films were grown on the flat and the vicinal Si(001) substrates by molecular beam epitaxy [5,11]. The growth was accomplished by first exposing the Sr/Si(001)-(2 × 1) surface to molecular oxygen, then co-evaporating Sr and Ti in the presence of molecular oxygen, which was found be kinetically favorable for Ti oxidation [11].…”

“…Additionally, interaction of alkaline earth metals such as Sr with Si has also received a considerable amount of attention due to its importance in growth of epitaxial oxide on Si(001) [5,6]. Fan et al investigated reconstruction of Si surface as a function of Sr coverage and temperature [7].…”