To predict the thin film thickness distribution in a quantitative way, a theoretical calculation was conducted according to the cosine law approach for off-axis sputtering. The numerical calculation was focused on the optimal geometry instead of the thickness distribution itself, which took into account several variables including the target-to-substrate distance, the off-axis displacement, the emission characteristic, the width of the erosion groove, and the film thickness requirement. The effects of these variables on the optimal geometry were analyzed individually and the subsequent combined equations for optimal geometry were summarized. Thus, the combined equations were multivariable functions. These equations were simple and general and could be applied directly. For many situations, these equations eliminate the need to perform the complex, detailed calculation otherwise needed for each deposition geometry variant. (c) 2007 American Vacuum Society.