Less than 10% pattern-dependent microloading and greater than 95%, step coverage are required for low temperature deposition of Si3N4 spacer and etch stop films in advanced logic and dynamic random access memory semiconductor applications. A single-wafer chemical vapor deposition chamber was utilized to analyze pattern loading effect on 130 nm and 90 nm patterned wafers. With silane-ammonia chemistry as the focus, a variety of processing methods were employed utilizing continuous and cyclical deposition modes. In addition, methods to modify diffusion and/or reaction rates were studied, such as remote plasma excitation and carrier gas modifications. Finally, chemistry-related variables were evaluated by changing the Si-source precursor, It was concluded that process chemistry and specifically precursor is the most dominant factor determining pattern loading effect. (c) 2005 American Vacuum Society.