IEEE International Conference on Solid Dielectrics
Electron irradiation experiments were conducted to investigate the electron transport, charging, discharging, cathodoluminescence and emission properties of high-conductivity carbon-loaded polyimide (Black KaptonTM). We discuss how these results are related to the nanoscale structure of the composite material. Measurements were conducted in an ultrahigh vacuum electron emission test chamber from <40 K to 290 K, using a monoenergetic beam with energies ranging from 3 keV to 25 keV and flux densities from 0.1 nA/cm2 to 100 nA/cm2 to deposit electrons in the material surface layer. Various experiments measured transport and displacement currents to a rear grounded electrode, absolute electron emission yields, absolute electron-induced photon emission yields and photon emission spectra (~250 nm to 1700 nm), and arcing rates and location. Numerous arcing events from the material edge to an electrically isolated grounded sample holder (particularly at lower temperatures) were observed, which are indicative of charge accumulation within the insulating regions of the material. Three types of light emission were also observed: (i) short duration (<1 s) arcing, (ii) long duration cathodoluminescence and (iii) intermediate duration (~100 s) glow. We discuss how the electron currents and arcing, as well as light emission absolute intensity and frequency, depend on electron beam energy, power, flux and temperature.
Evans, Amberly; Dennison, J. R.; Wilson, Gregory; and Dekany, Justin, "Nanodielectric Properties of High Conductivity Carbon-Loaded Polyimide Under Electron-Beam Irradiation" (2013). IEEE International Conference on Solid Dielectrics. Posters. Paper 17.