Modelling and simulating scanning force microscopes for estimating measurement uncertainty: a virtual scanning force microscope

A virtual scanning force microscope (virtual SFM) is established to assess the measurement uncertainty of SFMs, especially due to the SFM scanning apparatus and its non-ideal properties, to meet the increasing demand in industry and metrology. It builds numerical models for the individual errors from the instrument, the artefact or the environment, sequences the error models to simulate the measurement process, imitates the change of the measurement data during the whole measurement process to reveal the influences of these error sources, and calculates the measurement uncertainty from the statistical distribution of simulation results. The Monte Carlo method is applied to generate parameters within a given range of assumed values for the errors of the instrument, the sample and the set-up. In this paper, the principle and structure of the virtual SFM are introduced, its construction and simulation procedure are described, and a verification experiment is performed choosing a well-investigated instrument. The experiment result indicates that measurements can very well be simulated in the virtual SFM to obtain the measurement uncertainty if important parameters are determined.