Hard silicon carbonitride thin‐film coatings produced by remote hydrogen plasma chemical vapor deposition using aminosilane and silazane precursors. 1: Deposition mechanism, chemical structure, and surface morphology

Abstract

AbstractAmorphous silicon carbonitride films were produced by remote hydrogen microwave plasma chemical vapor deposition (RP‐CVD) using aminosilanes: (dimethylamino)dimethylsilane, bis(dimethylamino)methylsilane, and tris(dimethylamino)silane, as well as disilazanes: 1,1,3,3‐tetramethyldisilazane and 1,3‐bis(dimethylsilyl)‐2,2,4,4‐tetramethylcyclodisilazane as single‐source precursors. The effect of substrate temperature (TS) on the rate and yield of the RP‐CVD process, chemical composition, chemical structure, and surface morphology of resulting films is reported. The temperature dependencies of thickness‐based growth rate and growth yield of the film imply that for a low substrate temperature range (TS = 30–200°C), deposition rate and yield are limited by desorption of film‐forming precursors from a growth surface, whereas for a high substrate temperature range (TS = 200–400°C), the rate and yield values, independent of the temperature, are nearly constant and the RP‐CVD is a nonthermally activated process. The increase of the substrate temperature from 30°C to 400°C causes the elimination of organic groups from the film and the formation of a silicon carbonitride network structure with a predominant content of Si–N nitridic and Si–C carbidic bonds. On the basis of structural study and literature data, hypothetical elementary reactions contributing to the film formation process are postulated. The films were found to be morphologically homogeneous, defect‐free materials exhibiting very small surface roughness, which varied in a narrow range of values.