Study the surface charge of both original and corona-resistant Polyimide films by Electrostatic Force Microscope

Electrostatic Force Microscope (EFM) was applied to study the origin and decay properties of surface charge on original and corona-resistant Polyimide films in micro-nanometer scale. The surface charge were generated by injecting on the surfaces of the polyimide (PI) films using the conductive probe of EFM. After the surface charge were characterized by EFM, the results indicate that the difference origin and decay properties between original (100HN) and corona-resistant (100CR) polyimide films. Corona-resistant polyimide film accumulated less surface charge after injected charge and quicker decay, so the residual charge smaller than original Polyimide films. The decay time constant corresponding to the resistivity of each film. The research provides a new way for study on the rule and mechanism of generating and decaying surface charge on the insulated films and can be used to partially explain the mechanism of corona resistant.