Nitrogen (N) was successfully introduced into amorphous carbon (a-C) films by ablating carbon (C) from a camphoric carbon (CC) target with varying ambient N partial pressure (NPP) using pulsed laser ablation (PLA). We found that the N content in the film changed on varying the NPP The room temperature conductivity (aRT) decreases initially at 0.1 mTorr and then increases at higher NPP up to 30 mTorr and decreases thereafter. We can relate this variation, to doping of N in the films for low N content as the optical gap (E-g) remains unchanged till the film is deposited at 1 mTorr. Scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy and Raman spectroscopy studies also suggest that no graphitization whatsoever occurs in the film after N addition up to 1 mTorr. Although no structural change in the films was found with N addition up to 1 mTorr, the sigma(RT) depends on the N content. With higher NPP up to 30 mTorr, since E-g decreases with increasing sigma(RT), we related this phenomenon to the graphitization. However, above 30 mTorr, since E-g increases with the decrease of sigma(RT), we related this phenomenon to the structural change in the film. (C) 2002 Elsevier Science B.V. All rights reserved.