Abstract The geometries of several proposed new electronic device structures put constraints on the size of the AFM images that can be obtained in the gate areas. The images that can be obtained on these structures are of a significantly smaller area, at a much higher resolution, than is typically measured. The analysis areas are limited to ~ one-tenth of what is normally scanned. The micro-roughness and feature size information contained in AFM measurements changes with scan size. Care must be taken when introducing such a dramatic change in the measurements being made. Several factors should be considered to determine an appropriate sampling plan and select a proper reference set for these high-resolution measurements. In this paper, several of these factors are discussed in the context of determining a sampling plan and reference targets for sidewall micro-roughness of fins that allow 50 nm analysis areas.