Strong impact of SrTiO3/TiO2 buffer layer on epitaxial growth and dielectric response of Ba0.7Sr0.3TiO3 thin films on MgO

Shinya Kondo, Tomoaki Yamada, Masahito Yoshino, Takanori Nagasaki

Research output: Contribution to journalArticlepeer-review

Abstract

We demonstrate a significant improvement in the epitaxial growth of perovskite dielectric films on MgO by introducing a SrTiO3 (STO)/TiO2 buffer layer, which enhances their dielectric response. 270-nm-thick (001)-epitaxial (Ba,Sr)TiO3 (BST) films were deposited by pulsed laser deposition on STO/TiO2-buffered MgO with a SrRuO3 (SRO) bottom electrode. The film directly deposited on SRO/MgO grew in a three-dimensional mode, resulting in a rough and poorly crystalline film with an almost relaxed strain. On the other hand, the film with a buffer layer grew in a two-dimensional mode, resulting in a flat and highly crystalline film with a large compressive strain (%0.80%). As a result, the paraelectric-to-ferroelectric phase transition temperature increased by 220 °C and an out-of-plane dielectric constant exceeding 1000 was achieved.

Original languageEnglish
Article number0902B1
JournalJapanese Journal of Applied Physics
Volume57
Issue number9
DOIs
Publication statusPublished - Sep 2018
Externally publishedYes

ASJC Scopus subject areas

  • Engineering(all)
  • Physics and Astronomy(all)

Fingerprint

Dive into the research topics of 'Strong impact of SrTiO<sub>3</sub>/TiO<sub>2</sub> buffer layer on epitaxial growth and dielectric response of Ba<sub>0.7</sub>Sr<sub>0.3</sub>TiO<sub>3</sub> thin films on MgO'. Together they form a unique fingerprint.

Cite this