CORRELATION OF INSULATOR PROPERTIES WITH ELECTRON SPECTROSCOPIC OBSERVATIONS

Research of correlations between insulator macroscopic properties (ele ctric strength, mechanical toughness, friction, radiation damage sensi tivity, etc.) has shown that parameters related to polarization and en ergy dissipation processes are relevant for these properties. The inve stigation of the charging effect under an ionizing beam could be a way of characterizing polarization and relaxation processes leading to br eakdown, fracture, etc. The physical basis which allows to understand the degree of insulator charging phenomena is reviewed. A universal co ncept of trapping as well as the nature of the energy which is stored in a charged dielectric are recalled. Basic principles of charging and detrapping were verified on well defined materials. It was observed t hat the relaxation of the mechanical energy consecutive to an abrupt v ariation of the polarization is a major cause of defect generation lea ding to failures. Results achieved by electron spectroscopy are review ed. It is shown that there exist spectroscopic observations which can be related to parameters governing electric and mechanical strengths.