Poly( N-vinylcarbazole) (PVK) films have been deposited by the thermal evaporation technique. The films were doped with iodine either by using a pre-doped powder or by post-doping of the layer. While there are a lot of pinholes in the films obtained from iodine-doped PVK powder, the morphology of the post-doped films is better, without any inhomogeneities. Also, the iodine content is higher. By comparison to the reference powder, the modifications of the properties of the PVK layers induced by iodine doping after deposition are related to the smallest chain length. It is shown that polymerisation of the layer is induced by iodine; this effect is improved by mild heating (T=370 K).