Investigation of Surface Flashover on Dielectrics Enhanced by Excimer Laser Processing

One of the factors that contributes to surface flashover on dielectrics is the existence of defects on the surface of the material. For our studies, excimer laser processing was utilized on alumina dielectrics in an attempt to substantially increase the threshold voltages for flashover. Through excimer laser processing, the surface material melts and re-crystallizes to form a uniform surface structure. The defects on the dielectric surface can be minimized, reducing charge trapping, leading to higher flashover voltages. Two sets of samples were tested. The first set of samples was processed using the laser and the second set was not. The samples were then stressed under high voltage to induce surface flashover. Analysis of the effects of the excimer laser processing was performed and are shown