Resistance Change Method Research Articles

Electromigration reliability and activation energy of Bi2Te3 thermoelectric film

Reliability problems caused by metal electromigration failure have attracted much attention, but it is barely investigated for thermoelectric semiconductors with increased current density in micro thermoelectric devices. Herein, we investigate electromigration reliability of a Bi2Te3 thermoelectric film with the current densities of ∼104 A/cm2. The failure mechanism and thermoelectric performance change of the Bi2Te3 film at different current densities by controlling the temperature are discussed, indicating the reliability issue is a comprehensive problem involving multiphysics effects. In addition, the activation energy of Bi2Te3 materials, as an essential electromigration parameter, is measured and calculated to be about 0.8 eV by the resistance change method. This work provides much guidance to the reliable service of thin-film TE devices operating under high current density.

Determination of Temperature Rise of Energized Transformers by the Resistance Change Method

The problems of measurement of networks which remain energized by ac power during measurement are discussed. Particular attention is given to methods which permit continuous measurement with the aim of recording directly temperature rise as determined by the change of resistance. Deflection methods, as well as potentiometric and bridge methods, are treated, and their relative advantages in accuracy, convenience, cost, and complexity are considered. Results of heat runs on a 1/2-hp split-phase motor, a 3 kVA single-phase loaded transformer, and a 100-kVA three- phase transformer are included.