Charging phenomena, dielectric relaxation processes and breakdown of oxides
The study of insulator charging phenomena includes the origin of trapping, electrostatic energy dissipation mechanisms and the effects of that energy dissipation in catastrophe phenomena, such as breakdown and fracture, or even adhesion, wear and friction. It is shown that the polarisation of an insulator occurs either under application of a stress, or at the insulator-metal interface. Therefore, charging up effects are a particular case of polarisation in which carriers are trapped, this trapping being connected with the presence of defects and consequently with the local variations of the insulator susceptibility. The mechanisms of polarisation energy relaxation are complex, the main problem being the processes through which electrostatic energy is transferred to the phonon bath. Energy dissipation can occur either slowly, with a slight temperature rise and without modification of the solid, or with fast relaxation kinetics, producing catastrophe phenomena such as plasma initiation, mechanical fracture along the plasma path or mechanical shock wave damage. It is essential to characterise an insulator by its complex susceptibility, local variations of this susceptibility, and the kinetics of dipolar relaxation. Experiments were performed using scanning electron microscopy and surface science techniques.
Bibliographic Reference: Paper presented: QSA 6, London (GB), Nov. 13-16, 1990
Availability: Available from (1) as Paper EN 35848 ORA
Record Number: 199110043 / Last updated on: 1994-12-02
Original language: en
Available languages: en