| Abstract: | Photoconductivity measurements were carried out on plasma polymerized styrene (PPS) in vacuo, in air, and in subsequently re-evacuated conditions. Samples with two gold electrodes (Au-PPS-Au) and gold-aluminum electrodes (Au-PPS-Al) were used. Positive short circuit photocurrents in the direction of illumination were observed in both types of specimens. In the case of Au-PPS-Au, photocurrent threshold was about 1.6 eV in vacuo for the virgin film, which is attributed to the energy of hole generation in bulk. Residual free radicals were assumed to be the acceptors in this mechanism. In the case of Au-PPS-Al, electron injection from aluminum was thought to be a more likely mechanism, with an estimated barrier height of approximately 2.6 eV. |
