A method of PECVD deposition of silicon-containing films has been discovered and further developed. The method is particularly useful when the films are deposited on substrates having surface areas which are larger than 25,000 cm.sup.2. The method prevents the deposition of partially reacted silicon-containing species which form a powdery material or haze (contaminant compound) on the substrate surface. The contaminant compounds are avoided by assuring that the power applied to form a plasma in the PECVD process is maintained, at least at a minimal level, until reactive silicon-containing precursor gases present above the surface of the substrate have been reacted or evacuated from the plasma processing area.