| Abstract: | The high-field currents in poly-p-chloro-xylylene (PCPX) thin films are due to hole injection from anode metal and collision ionization. PPX thin films showed the negative temperature dependence of high-field currents. Since the chlorine atoms in PCPX thin films act as carrier scattering centers, high-field currents in PCPX thin films are suppressed in the low-temperature region. This paper discusses the high-field currents of PCPX/PPX composite thin films; these films are PCPX thin films (d < 150 nm) deposited on PPX thin films (d > 200 nm). They were strongly suppressed at room temperature, but not at low temperature. Therefore, PCPX/PPX composite thin films showed a remarkable negative temperature dependence of high-field currents. High-field currents were suppressed more in PCPX (60 nm)/PPX (230 nm) composite thin film than in PCPX (130 nm)/PPX (230 nm). This can be explained by the suppression of the hole injection from anode by homo space charge at the interface between PCPX/PPX. |
