skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Stabilization of ferroelectric phase in tungsten capped Hf 0.8 Zr 0.2 O 2

Authors:
 [1];  [2]; ORCiD logo [1];  [1];  [1];  [3]
  1. Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, California 94720, USA
  2. National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
  3. Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, California 94720, USA, Energy Storage and Distributed Resources Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, California 94720, USA
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1369483
Grant/Contract Number:
AC02-05CH11231
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Applied Physics Letters
Additional Journal Information:
Journal Volume: 111; Journal Issue: 2; Related Information: CHORUS Timestamp: 2018-02-14 14:13:21; Journal ID: ISSN 0003-6951
Publisher:
American Institute of Physics
Country of Publication:
United States
Language:
English

Citation Formats

Karbasian, Golnaz, dos Reis, Roberto, Yadav, Ajay K., Tan, Ava J., Hu, Chenming, and Salahuddin, Sayeef. Stabilization of ferroelectric phase in tungsten capped Hf 0.8 Zr 0.2 O 2. United States: N. p., 2017. Web. doi:10.1063/1.4993739.
Karbasian, Golnaz, dos Reis, Roberto, Yadav, Ajay K., Tan, Ava J., Hu, Chenming, & Salahuddin, Sayeef. Stabilization of ferroelectric phase in tungsten capped Hf 0.8 Zr 0.2 O 2. United States. doi:10.1063/1.4993739.
Karbasian, Golnaz, dos Reis, Roberto, Yadav, Ajay K., Tan, Ava J., Hu, Chenming, and Salahuddin, Sayeef. Mon . "Stabilization of ferroelectric phase in tungsten capped Hf 0.8 Zr 0.2 O 2". United States. doi:10.1063/1.4993739.
@article{osti_1369483,
title = {Stabilization of ferroelectric phase in tungsten capped Hf 0.8 Zr 0.2 O 2},
author = {Karbasian, Golnaz and dos Reis, Roberto and Yadav, Ajay K. and Tan, Ava J. and Hu, Chenming and Salahuddin, Sayeef},
abstractNote = {},
doi = {10.1063/1.4993739},
journal = {Applied Physics Letters},
number = 2,
volume = 111,
place = {United States},
year = {Mon Jul 10 00:00:00 EDT 2017},
month = {Mon Jul 10 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on July 13, 2018
Publisher's Accepted Manuscript

Citation Metrics:
Cited by: 1work
Citation information provided by
Web of Science

Save / Share:
  • A series of Pb(Zr{sub 1-x}Ti{sub x})O{sub 3} multilayer films consisted of Pb(Zr{sub 0.8}Ti{sub 0.2})O{sub 3} and Pb(Zr{sub 0.2}Ti{sub 0.8})O{sub 3} were deposited on Pt/Ti/SiO{sub 2}/Si substrates by using radio frequency magnetron sputtering. All the films comprise six periodicities of Pb(Zr{sub 0.8}Ti{sub 0.2})O{sub 3}/Pb(Zr{sub 0.2}Ti{sub 0.8})O{sub 3} with periodicity thickness of 133 nm, but the layer thicknesses of rhombohedral phase and tetragonal phase in one periodicity are varied. The films with two layer thickness ratio of 1:3 possess enhanced dielectric and ferroelectric properties: dielectric constant {epsilon}{sub r}=328 at 10 kHz, dielectric loss tg{delta}=0.0098, and sharply enhanced remanent polarization P{sub r}=32.6 {mu}C/cm{supmore » 2}. The layer structure and interlayer stress of Pb(Zr{sub 1-x}Ti{sub x})O{sub 3} multilayer films play important roles in the electric enhancement.« less
  • We report on the ferroelectricity for morphotropic-phase-boundary lead (Pb) free 0.5BaTi{sub 0.8}Zr{sub 0.2}O{sub 3}-0.5Ba{sub 0.7}Ca{sub 0.3}TiO{sub 3} (0.5BZT-0.5BCT) thin films. Thin films were grown on Pt/Ti/SiO{sub 2}/Si substrate using pulsed laser deposition. Raman spectroscopic data combined with the X-ray diffraction analyses confirm body centered tetragonal crystallographic structure 0.5BZT-0.5 BCT thin films on Pt/Ti/SiO{sub 2}/Si. Polarization studies demonstrate that these 0.5BZT-0.5BCT films exhibit a large remnant and saturation polarization of 37 μC/cm{sup 2} and 40 μC/cm{sup 2}, respectively, with a coercive field of 140 kV/cm. A correlation between polarization dynamics, structural distortion, and phonon vibration is established. The splitting of X-ray diffraction peak ofmore » the thin film in the 2θ range of 44.5° to 46.5° represents high degree of tetragonality. The tetragonality factor calculated by Rietveld analysis was found to be 0.006 and can be a major cause for the increased remnant polarization value. It is established from Raman spectra that the non-centrosymmetricity due to the displacement of Ti/Zr ions from its octahedral position is related to the peak position as well as the broadening of the A{sub 1} (LO) optical phonon mode. This increase of broadness in the thin film causes an increase in the dipole moment of the unit cell and, hence, the net increase in polarization values.« less
  • The structural and electrical properties of epitaxial Pb(Zr{sub 0.2}Ti{sub 0.8})O{sub 3} thin films grown on 2 in. (001) silicon wafers were investigated. Using x-ray diffraction, the lattice behavior of the heterostructure has been studied as a function of temperature, suggesting a 250 deg. C increase of the Pb(Zr{sub 0.2}Ti{sub 0.8})O{sub 3} ferroelectric-paraelectric transition temperature with respect to the bulk value. This significant enhancement of the critical temperature is understood in terms of a two-dimensional clamping effect.
  • Pb(Zr{sub 0.8}Ti{sub 0.2})O{sub 3} (PZT80/20) thin films were deposited on the Pt(111)/Ti/SiO{sub 2}/Si(100) substrates by RF magnetron sputtering. Mainly perovskite crystalline phase with highly (202)-preferred orientation, determined by x-ray diffraction, was formed in the lead zirconate titanate (PZT)(80/20) thin films. Polarization measurements of the unannealed and aged films showed a clear double hysteresis loop. However, the double hysteresis loop phenomenon was greatly suppressed in the PZT thin films annealed under pure oxygen, and thus they exhibited larger remnant polarization (P{sub r} = 6.3 {mu}C/cm{sup 2}). The related mechanism for the appearance of constricted and double hysteresis loops was investigated tomore » be associated with the realignment and disassociation of defect dipoles via oxygen octahedral rotations or oxygen vacancy diffusion. The butterfly-shaped C-V characteristic curve with a valley gave further evidence for double hysteresis loop characteristic in the unannealed and aged PZT thin films.« less
  • We introduce an in situ vacuum procedure for the optimal preparation and analysis of self-assembled monolayers (SAMs) as used in organic molecular electronics on ferroelectric lead zirconate titanate (PZT) substrates. Excellent ordering of oligothiophene semiconductor layers is heavily promoted through the presence of an interfacial bi-functional SAM layer that binds to both the oxidic PZT surface and the organic semiconductor molecules. The described method can be extended to other material combinations, featuring a variety of substrate materials and molecular functionalities.