Electronic defect and trap-related current of (Ba0.4Sr0.6)TiO3 thin films

Abstract

By employing a deep level transient spectroscopy (DLTS) technique, this work investigates the deep trap levels of rf-sputtered (Ba0.4Sr0.6)TiO3 (BST) thin films deposited at various temperatures. Arrhenius plots of DLTS spectra detect a single trap located at 0.45 eV in 450 °C deposited films, whereas two traps located at 0.2 and 0.40 eV appear in 550 °C deposited films. On the other hand, examining the I–V characteristics of the films at the temperature range of 298–403 K reveals the presence of two conduction regions in the BST film capacitors, having ohmic behavior at low voltage (<1 V) and Schottky-emission or Poole–Frenkel mechanism at high voltage (>6 V). The barrier height and trapped level are, respectively, estimated to be 0.46 and 0.51 eV, corresponding to the trap activation energy 0.4–0.45 eV obtained from our DLTS measurements. Compared with previous published reports, the trap distributed at 0.4–0.5 eV should be an intrinsic defect of BST and possibly ascribed to be oxygen vacancies. Meanwhile, the trap plays a prominent role in the leakage current of BST films.

Dielectric properties of BaMg1∕3Nb2∕3O3 doped Ba0.45Sr0.55Tio3 thin films for tunable microwave applications

“…approximation method from which potential barrier height of 1.3 eV and trap ionization potential of 0.4 eV for the respective films were extracted. Interestingly, the numbers are found to be fairly comparable with the reported barrier height for the SE model, 35,36,43 and trap ionization energy for PF model 39,43 in BST and related perovskite thin films. The analysis in both films revealed that while the formation of Schottky potential barrier at the interface dominates the carrier transport in the undoped BST film, the BMN doped BST film is controlled by traps sitting in bulk of the film.…”

Leakage-current characteristics of vanadium- and scandium-doped barium strontium titanate ceramics over a wide range of DC electric fields

“…Fig. 4b shows that our data (data points) is consistent with the predictions for this mechanism (solid line), consistent with other reports that this mechanism dominates at high fields [22][23][24]. Fig.…”

“…However, others have reported that that thermionic emission at internal interfaces, such as grain boundaries, can dominate conduction in Ba x Sr 1Àx-TiO 3 [22,23]. Although the observed thermally activated electrical properties (Fig.…”

Effect of vanadium doping on ferroelectric and electrical properties of Bi3.25La0.75Ti3O12 thin film

“…Compared with previous results, it is reported the Schottky barrier height of SBT/SBN thin films in the range of about 1 eV [15,21]. The barrier height [24][25][26] of Ba 0.4 Sr 0.6 TiO 3 , Ta 2 O 5 and PZT thin films is 0.46 eV, 0.36 eV and about 0.6 eV, respectively. The Schottky barrier height of B = 0.2 eV for BLTV thin films is lower than that of other results.…”