Improved properties of barium strontium titanate thin films grown on copper foils by pulsed laser deposition using a self-buffered layer
Journal
Journal of Physics D-Applied Physics
Journal Volume
45
Journal Issue
17
Pages
175304
Date Issued
2012
Author(s)
Liu, Shanshan
Ma, Beihai
Narayanan, Manoj
Chao, Sheng
Koritala, Rachel
Balachandran, Uthamalingam
Abstract
Abstract Ba 0.6 Sr 0.4 TiO 3 (BST) films were deposited by pulsed laser deposition on copper foils with low-temperature self-buffered layers. The deposition conditions included a low oxygen partial pressure and a temperature of 700 °C to crystallize the films without the formation of secondary phases and substrate oxidation. The results from x-ray diffraction and scanning electron microscopy indicated that the microstructure of the BST films strongly depended on the growth temperature. The use of the self-buffered layer improved the dielectric properties of the deposited BST films. The leakage current density of the BST films on the copper foil was 4.4 × 10 −9 A cm −2 and 3.3 × 10 −6 A cm −2 with and without the self-buffered layer, respectively. The ferroelectric hysteresis loop for the BST thin film with buffer layer was slim, in contrast to the distorted loop observed for the film without the buffer layer. The permittivity (7 0 0) and dielectric loss tangent (0.013) of the BST film on the copper foil with self-buffered layer at room temperature were comparable to those of the film on metal and single-crystal substrates.
SDGs
Type
journal article