Thin polyaniline (PAN) films were prepared by evaporation of emeraldine base in vacuum at 275-325 degrees C, followed by deposition of the vapors onto SnO2-glass transparent electrodes. With the purpose to restore the original structure of the polymer, the films were subjected to a postdeposition oxidative treatment in HNO3 according to the following three different procedures: (1) treatment in vapors of 10 M acid, (2) treatment in 2 M HNO3 aqueous solution, (3) cyclic treatment: in 2 M aqueous HNO3, then in 2 M aqueous NH, and so on. Electrochemical and spectroelectrochemical characteristics, namely cyclic voltammetry curves at different sweep rates and optical spectra at stationary potentials, were investigated for these films. It was found that the above characteristics of the films oxidized according to the cyclic procedure are most close to those of conventional PAN. However, in the optical spectra recorded at 0.0 V (vs. Ag/AgCl) for all the vacuum deposited films no absorption band in the area longer than 800 nm was observed. The results are discussed in terms of correlation of changes in the spectroelectrochemical characteristics with formation of heterogeneous structure of PAN by means of arising of intermolecular interactions, as well as, with specific features of vacuum the deposited PAN films.