Photoconduction in Poly(p-Phenylene Sulfide) Films near the Absorption Edge

Steady state photocurrent of pristine poly(p-phenylene sulfide) with a rather low impurity content was measured under the condition of low light intensity and a low applied electric field. A very sharp peak in the photocurrent spectrum was observed at 370 nm in the vicinity of the absorption edge. The photocurrent increased linearly with the light intensity and with the applied electric field, while it was only slightly affected by the polarity of the applied voltage. These experimental results can be explained by the diffusion model of photocarriers with the very large surface recombination rate under the low applied field. Temperature dependence of the photocurrent and dark conductivity is also discussed.