This paper reports on the preparation and characterization of films of plasma silicon nitride, deposited on Si substrates from , , and Ar. It is shown that the deposition rate and uniformity of the films are strongly affected by the cleaning and loading of the reactor. Pinhole densities are reduced by increase of both the film thickness and the deposition temperature. Several parameters were systematically varied, including the deposition temperature (20°–500°C), RF power (10–300W), chamber pressure (0.5–1.4 torr), and gas flow rates. At 500°C specular films are grown with the following characteristics: refractive index 1.9–2.1, pinhole density 5 cm−2 at 1.0 μm thickness, 100 Å/min etch rate in buffered , and good stability to annealing. Relationships between deposition parameters and film characteristics, including deposition rate, etch rate, and index of refraction, are discussed in terms of current understanding of the deposition process. An explanation is offered for differences in the effect of RF power level on deposition rates observed by other investigators.