Spectroscopic ellipsometry study of SrBi2Ta2O9 ferroelectric thin films

被引：48

作者：

Bahng, JH ^{[1
]}

Lee, M

Park, HL

Kim, IW

Jeong, JH

Kim, KJ

机构：

[1] Yonsei Univ, Dept Phys, Seoul 120749, South Korea

[2] Yonsei Univ, IPAP, Seoul 120749, South Korea

[3] Univ Ulsan, Dept Phys, Ulsan 680749, South Korea

[4] Pukyong Natl Univ, Dept Phys, Pusan 680737, South Korea

[5] Konkuk Univ, Dept Phys, Seoul 143701, South Korea

来源：

APPLIED PHYSICS LETTERS | 2001年 / 79卷 / 11期

关键词：

D O I：

10.1063/1.1402654

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

Optical properties of SrBi2Ta2O9 (SBT) ferroelectric thin films were investigated by spectroscopic ellipsometry at room temperature in the 1.5-5.5 eV spectral range. The films were grown on platinized silicon (Pt/Ti/SiO2/Si) with a Bi/Sr ratio (x) range from 1.2 to 2.8 by pulsed-laser deposition. The measured pseudodielectric functions of the samples indicate the band-gap energy of SBT shifts to lower energies as x increases. The optical constants and band-gap energies of the SBT films were determined through multilayer analyses on their pseudodielectric functions. The band-gap energy of SBT is found to shift to lower energies quite linearly with x. The band-gap energy at stoichiometric composition (x=2) is estimated to be 4.1 eV. (C) 2001 American Institute of Physics.

引用

页码：1664 / 1666

页数：3

共 17 条

[1] MODEL DIELECTRIC-CONSTANTS OF GAP, GAAS, GASB, INP, INAS, AND INSB [J].