Structural, optical, and electrical properties of strained La-doped SrTiO3 films

被引：55

作者：

Choi, Miri ^{[1
]}

Posadas, Agham B. ^{[1
]}

Rodriguez, Cesar A. ^{[2
]}

O'Hara, Andrew ^{[1
]}

Seinige, Heidi ^{[1
]}

Kellock, Andrew J. ^{[3
]}

Frank, Martin M. ^{[4
]}

Tsoi, Maxim ^{[1
]}

Zollner, Stefan ^{[2
]}

Narayanan, Vijay ^{[4
]}

Demkov, Alexander A. ^{[1
]}

机构：

[1] Univ Texas Austin, Dept Phys, Austin, TX 78712 USA

[2] New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA

[3] IBM Corp, Almaden Res Ctr, San Jose, CA 95120 USA

[4] IBM Corp, Thomas J Watson Res Ctr, Yorktown Hts, NY 10598 USA

来源：

JOURNAL OF APPLIED PHYSICS | 2014年 / 116卷 / 04期

基金：

美国国家科学基金会;

关键词：

DIELECTRIC-PROPERTIES; STRONTIUM-TITANATE; MOBILITY; SILICON; BULK; SUPERCONDUCTIVITY;

D O I：

10.1063/1.4891225

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

The structural, optical, and room-temperature electrical properties of strained La-doped SrTiO3 epitaxial thin films are investigated. Conductive La-doped SrTiO3 thin films with concentration varying from 5 to 25% are grown by molecular beam epitaxy on four different substrates: LaAlO3, (LaAlO3)(0.3)(Sr2AlTaO6)(0.7), SrTiO3, and DyScO3, which result in lattice mismatch strain ranging from -2.9% to +1.1%. We compare the effect of La concentration and strain on the structural and optical properties, and measure their effect on the electrical resistivity and mobility at room temperature. Room temperature resistivities ranging from similar to 10(-2) to 10(-5) Omega cm are obtained depending on strain and La concentration. The room temperature mobility decreases with increasing strain regardless of the sign of the strain. The observed Drude peak and Burstein-Moss shift from spectroscopic ellipsometry clearly confirm that the La addition creates a high density of free carriers in SrTiO3. First principles calculations were performed to help understand the effect of La-doping on the density of states effective mass as well as the conductivity and DC relaxation time. (C) 2014 AIP Publishing LLC.

引用

页数：10

共 65 条

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