Optical, dielectric and fatigue properties of sol gel-derived 2 µm thick Pb(Zr_0.53Ti_0.47)O₃ferroelectric films

Abstract

Lead zirconate titanate (PZT) thin films of thickness ≈2µm with a composition near the morphotropic phase boundary are successfully deposited on platinum-coated silicon substrates. The crystallization phase starts to appear at 500ºC. The crystal structure, optical and electrical properties are investigated in relation to the thickness and annealing temperature of the films. The dielectric constant is observed to increase as thickness goes up to ≈1.28µm, and remains constant above that. At 700ºC, the dielectric constant and dissipation factor of ≈ 2µm thick PZT film are ≈850 and ≈0.03, respectively. The film exhibits good optical transmissivity, and has a direct optical transition. The band gap of a film annealed at 700ºC is found to be 3.34 eV. It has been observed that the n(λ) data can be fitted to a Sellmeier-type dispersion relation. Ferroelectric PZT shows almost no degradation in its polarization after 104 switching cycles at an applied voltage of 5 V. The results of this study confirm that ferroelectric PZT thin films are very useful for applications in a variety of devices such as ferroelectric memories and microelectromechanical systems.

ZnS thin films deposition by thermal evaporation for photovoltaic applications

“…The obtained disorder is equal to160 meV. The refractive index was estimated by fitting the transmittance curve according to References [27,28]. In Figure 6, we present the variation of the estimated refractive index as a function of the wavelength.…”

Locking of electric-field-induced non-180° domain switching and phase transition in ferroelectric materials upon cyclic electric fatigue

“…Such behavior has therefore been the topic of extensive study in the past few years. [5][6][7][8][9][10][11][12][13][14][15][16][17][18] There are two main approaches to the analysis of ferroelectric fatigue. One approach is through investigation of the change of the material properties, such as the reduction of remanent polarization and piezoelectric constants.…”

“…One approach is through investigation of the change of the material properties, such as the reduction of remanent polarization and piezoelectric constants. [5][6][7][8][9][10][11][12][13] Another approach is by observing the locking of switchable domains directly. 14,15 To date, the observation has only been conducted to detect the locking of 180°domain switching, although some efforts have been made to distinguish the 180°domain switching from the non-180°d omain switching.…”