The change in oscillation frequency of a cantilever is proportional to the mass on top of the cantilever and to the amplitude of vibration. This causes a cross-sensitive between both effects and makes it difficult to have proper detection with a single cantilever beam. The goal of this project is to decouple both effects by engineering a mode shape to maintain as constant as possible the vibrational amplitude at the region of interest (typically the free edge of the cantilever). I perform this mode shape engineering by fabricating cantilever structures with a region where the stiffness is discontinuous in the cross section, over a portion of the length.