Effect of modification of copper electrode on the space charge accumulation in LDPE

Abstract

In this paper, titanium and tungsten films were coated on copper sheets, respectively, by plasma chemical vapor deposition (PCVD). The copper sheets before and after coating were, respectively, injected as charge into the low-density polyethylene (LDPE), the space charge accumulation in LDPE was tested by the thermally stimulated current (TSC), and the trap level of the dielectric was calculated by the TSC curve. The results show that the work function improves after the modification of the electrode material, the space charge accumulation in LDPE decreases, and the trap level of the polymer reduces. Because of the oxygen vacancies, the titanium coating electrode has significant suppression on the charge injection in LDPE under 30 kV/mm and the tungsten shows excellent inhibition under 70 kV/mm.