Texture and phase variation of ALD PbTiO3 films crystallized by rapid thermal anneal
Abstract
PbTiO3 (lead titanate) thin films were deposited by atomic layer deposition (ALD) and crystallized via rapid thermal anneal. The films were grown using lead bis(3-N,N-dimethyl-2-methyl-2-propanoxide) and tetrakis dimethylamino titanium as cation precursors. A combination of H2O and ozone was used as oxidizers. Phase-pure, stoichiometric PbTiO3 was confirmed using x-ray diffraction, Rutherford backscattering spectroscopy, and scanning transmission electron microscopy. Ferroelectric hysteresis loops obtained by patterning circular capacitors with areas of 4.92 × 10−4 cm2 indicate a Pmax = 48 μC/cm2, 2Pr = 60 μC/cm2, Ec1 = −73 kV/cm, Ec2 = 125 kV/cm, and a leakage current density of 15 μA/cm2 at 138 kV/cm. Capacitance versus voltage measurements were used to obtain a maximum dielectric constant of 290 at 85 kV/cm and loss tangent under 4% tested in the range of ±275 kV/cm. ALD PbTiO3 grown with near-ideal cation ratios crystallized into randomly oriented perovskite grains when grown on a sputtered Pt-coated Si substrate. A variation of rapid thermal anneal temperatures, ramp rates, and nucleation layers was investigated and did not have a significant effect on perovskite grain orientation.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 04, 2019
- Source ID
- 10.1116/1.5080226
Entities
People
- Daniel M. Potrepka
- Jacob L. Jones
- Jeffrey S. Pulskamp
- Nicholas A. Strnad
- Raymond J. Phaneuf
- Ronald G. Polcawich
- Yang Liu
Organizations
- National Nanotechnology Initiative
- National Science Foundation
- North Carolina State University
- United States Army Materiel Command
- University of Maryland