The coverage properties of silicon nitride (Si3N4) films prepared by the catalytic chemical vapor deposition (Cat-CVD) technique were systematically studied. By increasing the catalyzer-substrate distance, the coverage was improved from 46 to 67% on a 1.0-mum line and space pattern. The etching rate of Cat-CVD Si3N4 film measured using 16BHF solution was independent of the deposited position of the micro-patterns deposited, and was approximately 3 nm/min, one order of magnitude lower than that of plasma-enhanced CVD (PE-CVD) Si3N4 film. This means that Cat-CVD Si3N4 films are denser than PE-CVD Si3O4 films, and that the quality at the side wall is equivalent to that on the top surface. That is, Cat-CVD Si3N4 films show a passivation effect, which was excellent, even at the side wall of micro-patterns. These results suggest that Si3N4 films prepared by Cat-CVD are suitable for the passivation films in microelectronic devices having a step configuration, such as TFT-LCDs and ULSIs. (C) 2003 Elsevier Science B.V. All rights reserved.