Surface finish improvement of deep micro bores monitored using an active MEMS cantilever probe

Application of a novel MEMS cantilever probe is described which is designed for non-destructive profilometry with micro machined surfaces, e.g., inside high-aspect-ratio micro bores. As an actual topic of industrial production the surface finish of diesel injector nozzle spray holes is investigated for a variety of state-of-the-art nozzle types. We address the performance of the sensor (resolution, uncertainty, speed) and the limits of the method to determine the reproducibility of a micro bore fabrication process as well as its optimization.