The temperature dependence of the conduction current in Ba0.5Sr0.5TiO3 thin-film capacitors for memory device applications

Abstract

The temperature dependence of the current–voltage characteristics of Ba0.5Sr0.5TiO3 (BST) thin-film capacitors was studied from 300 to 433 K. An Au/BST/Pt/Ti/SiO2/Si structure was used. The BST films were deposited by rf magnetron sputtering. The conduction current was dominated by Schottky emission at room temperature and by Poole–Frenkel emission above 403 K. The dominant conduction mechanism changed from Schottky emission to Poole–Frenkel emission in the temperature range from 373 to 403 K. The BST/Pt and the BST/Au Schottky barrier heights were found to be 0.88 and 0.72 eV, respectively. The trap energy level in BST was 0.83 eV.

Effect of Oxygen Concentration on Characteristics of Ba(Zr0.1Ti0.9)O3Thin Films Deposited on Indium Tin Oxide/Glass Substrates

“…The fitting curves were straight in this figure and the J-E curves of thin films thus follow the Poole-Frenkel emission model. 13,14) From the above results, the leakage currents of thin films above 200 kV/cm for 0 and 40% oxygen concentrations were fitted well by straight lines. The conduction mechanism of thin films with 40% oxygen concentration under the high electrical field follows the Schottky emission model.…”

“…Figure 9(a) shows the leakage current density versus electrical field characteristics in terms of J=T 2 on the vertical axis and E 1=2 on the horizontal axis. If the J-E curves obey the Schottky emission model, the fitting curves should be straight in this Figure. 13,14) At 0% oxygen concentration, the leakage current of thin films above 400 kV/cm was fitted well by straight lines in this study. Figure 9(b) also shows the same J-E characteristics in terms of J=E on the vertical axis and E 1=2 on the horizontal axis.…”

Effect of uniform and periodic doping by Ce on the properties of barium strontium titanate thin films

“…At high fields (>18 MVm −1 ), the leakage current is considerably reduced for small additions of Ce up to 0.005, beyond which the leakage current again increases. However, at low fields, the leakage current is higher for x=0.002 but decreases to below that of the undoped film for x=0.005; a further increase in the Ce The leakage current in the BST thin films is usually analyzed in terms of two groups of mechanisms-interface limited such as Schottky emission or bulk limited which include space charge limited current, Poole-Frenkel mechanism and the hopping conduction mechanism [34,35]. As discussed later, in the multilayer films also, there are significant changes in the leakage current with the multilayer configuration.…”

Improvement of Electrical Properties of $\hbox{Ba}_{{\bf 0.7}}\hbox{Sr}_{\bf 0.3}\hbox{TiO}_{\bf 3}$ Capacitors With an Inserted Nano-Cr Interlayer

“…The dynamic relative dielectric constant can be inferred from n 2 , where n is the refractive index. Therefore, the dynamic relative dielectric constant of BST films is about 4 [16].…”