Abstract: A disc-shaped plasma, generated by a ring-shaped cold cathode is used both as an in-situ large area (10-20 cm in diameter) VUV lamp and as a source of ground state and excited atoms. The atoms created in the disc-shaped plasma may be used for initiating sensitized atom-molecule reactions in the volume that dissociate the molecules as well as for providing external energy to heterogenous surface reactions. Multiple grid electrodes are used to extract ions or electrons from the plasma during the deposition process. The disc-shaped plasma is of narrow width which is optically thin for resonance photons emitted in a direction perpendicular to the disc to minimize undesired resonance trapping and associated line reversal. This VUV lamp operates without the need for optical windows; hence, ground state and excited atoms, created in the disc-shaped plasma, can diffuse from the disc-shaped plasma toward the substrate.