High resistivity and low dielectric constant amorphous carbon nitride films: application to low-k materials for ULSI

Amorphous carbon nitride films, a-CNx, have been candidates for interlayer insulator materials on ultra large-scale integration (ULSI). The most important property of insulators for ULSI application is low dielectric constant, i.e. low-k. It is reported in this paper the success in preparing carbon nitride films with dielectric constant less than 2. The sample films are prepared by a layer-by-layer method. The preparation consists of two cyclic processes. First process is a preparation of a-CNx thin layer by a nitrogen radical sputtering. Second process is a treatment of a-CNx layer by atomic hydrogen. To understand the characteristic low-k by atomic hydrogen treatment and by a layer-by-layer process, we have studied the effect of hydrogen radicals to a-CNx to get lower dielectric constant materials. (C) 2002 Elsevier Science B.V. All rights reserved.