A high quality and UV-transparent plasma enhanced chemical vapor deposition (PECVD) silicon nitride film is well developed to form a passivation layer for non-volatile memory devices. The dependence of the film properties on process parameters has been studied by factorial designed experiments. The deposition rate, uniformity, stress, refractive index, wet etching rate, density, step coverage, and UV-transmittance are the items used to evaluate the film properties. Rutherfold backside scattering (RBS) and hydrogen forward scattering (HFS) are used to measure the film composition and total hydrogen composition, respectively. Compared to the traditional PECVD nitride (PE-SiN) film known to have tensile stress and opacity to ultra-violet light (UV light), the developed PE-SiN film with very low compressive stress (< 1E9 dynes/cm*2) and excellent UV-transmittance (> 70% for 1.6 micrometers - thick film) can be achieved. The developed film has higher density, lower hydrogen content, and high N/Si inside film. Based on RBS/HFS, UV-transmittance and Fourier transform infrared spectrum (FTIR) results, the material and optical properties of the developed PE-SiN film are well investigated. This developed PE-SiN film is successfully applied to EPROM devices, and very good electrical and reliability performances have been demonstrated.