Thin Si3N4films were grown on Si by direct exposure to a low‐temperature (250–650 °C) nitrogen glow discharge at 13.56 MHz. The activation energy for growth is 0.3±0.12 eV. Their chemical and electronic, bulk, and interfacial properties are studied as a function of the film thickness and growth temperature. The ultrathin films (d<100 A˚) exhibit an average breakdown field of 10–12 MV/cm, a dielectric constant equal to 5.5, and are effective barriers against oxidation at 1000 °C. Conduction in ultrathin films is via Fowler–Nordheim tunneling over the temperature range 77–420 K. Deep‐level transient spectroscopy analysis reveals the presence of two majority‐carrier (hole) traps at the interface, with activation energies 0.1 and 0.35 eV, respectively. The trap atEV+0.35 eV is attributed to the Si dangling bond defect while the trap atEV+0.1 eV could be attributed to a structural defect that isinsituannealed at growth temperatures higher than 500 °C. The interface state concentration is a sensitive function of the growth temperature and varies in the range 8×1010–6×1012cm−2.