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.

The degradation of non-Ohmic electrical characteristics of ZnO–glass chip varistors due to high-intensity impulse currents was correlated with the deep trap levels investigated by means of deep level transient spectroscopy. Three electron traps located at 0.11, 0.27, and 0.94 eV below the conduction band were observed for chip varistors before current impulse testing. These trap energy depths of the chip varistors after current impulse testing were found to be almost unchanged, but their trap densities and capture cross sections both decreased. The concentration of the trap at 0.94 eV was decreased and ascribed to oxygen vacancies existing at the grain boundaries of the varistor. The electrical degradation phenomenon of the chip varistors is closely related to the reaction between the trap at 0.94 eV and adsorbed oxygen ions at the grain boundaries.

Based on the application drawback of the conventional motor reciprocating within certain angle, a novel permanent magnet arc guideway motor (PMAGM) is put forward which directly converts electrical current into limited angular moment, producing torque through a limited rotation angle of normally much less than ±180°. According to the permanent magnet (PM) magnetization and solenoid coil electrifying modes, five different magnetization orientations and three different electrifying modes are analysed. Results show that electromagnetic force of Y direction magnetized alone the external field force lines is larger than any other magnetization orientations, 40% higher than that of vertical magnetization. X direction electromagnetic force magnetized alone the external field force lines in proposal 3 is 2.5 times that of the vertical magnetization in proposal 2. The electromagnetic force and dynamic response performance of designed PMAGM could be improved effectively and provided with certain practical significance.