Polar and non-polar domain borders in MgO ultrathin films on Ag(001)

被引：32

作者：

Ferrari, AM

Casassa, S

Pisani, C

Altieri, S

Rota, A

Valeri, S

机构：

[1] Univ Turin, Dipartimento Chim IFM, I-10125 Turin, Italy

[2] Univ Turin, Ctr Excellence, I-10125 Turin, Italy

[3] INFM, Natl Res Ctr NanoStruct & Biosyst Surfaces, I-41100 Modena, Italy

[4] Univ Modena, Dipartimento Fis, I-41100 Modena, Italy

来源：

SURFACE SCIENCE | 2005年 / 588卷 / 1-3期

关键词：

thin film structure and morphology; interface structure and roughness; scanning tunnelling microscopy; dielectric thin films; electronic structure; DFT calculations;

D O I：

10.1016/j.susc.2005.05.043

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The morphology of ultrathin epitaxial MgO layers reactively grown at 470 K and at 1 ML min(-1) on Ag(001) was investigated by scanning tunnelling microscopy (STM). At deposition of 13 and 2,6 ML. square MgO domains of about (10 x 10) nm(2) form. On mono- and bi-layer domains. edges are mainly oriented along the (110) oxide direction, corresponding to polar (P) borders. while on multi-layer domains also non-polar (NP) borders appear. corresponding to the (100) orientation. By using periodic models and ab initio DFT calculations, the energetics of the two orientations was studied. Interaction with the metal substrate was found to strongly reduce the instability of P borders, although not enough to make the two orientations equally stable. The results are discussed. also with reference to conflicting experimental evidence from other laboratories. (c) 2005 Elsevier B.V. All rights reserved.

引用

页码：160 / 166

页数：7

共 25 条

[1] Electronic structure and chemical reactivity of oxide-metal interfaces: MgO(100)/Ag(100) [J].