Drift-insensitive distributed calibration of probe microscope scanner in nanometer range: Virtual mode

TL;DR

This paper introduces a drift-insensitive distributed calibration method for probe microscope scanners in the nanometer range, utilizing a virtual mode for simulation, correction of distortions, and analysis of thermal effects.

Contribution

It presents a novel distributed calibration approach using local calibration coefficients and a virtual mode for simulation and analysis of raster distortions and thermal effects.

Findings

Calibration database enables correction of spatial distortions.

Virtual mode allows simulation and detailed analysis of raster distortions.

Method effectively estimates thermal drift and creep velocities.

Abstract

A method of distributed calibration of a probe microscope scanner is suggested which main idea consists in a search for a net of local calibration coefficients (LCCs) in the process of automatic measurement of a standard surface, whereby each point of the movement space of the scanner can be characterized by a unique set of scale factors. Feature-oriented scanning (FOS) methodology is used as a basis for implementation of the distributed calibration permitting to exclude in situ the negative influence of thermal drift, creep and hysteresis on the obtained results. Possessing the calibration database enables correcting in one procedure all the spatial distortions caused by nonlinearity, nonorthogonality and spurious crosstalk couplings of the microscope scanner piezomanipulators. To provide high precision of spatial measurements in nanometer range, the calibration is carried out using natural standards - constants of crystal lattice. One of the useful modes of the developed calibration method is a virtual mode. In the virtual mode, instead of measurement of a real surface of the standard, the calibration program makes a surface image "measurement" of the standard, which was obtained earlier using conventional raster scanning. The application of the virtual mode permits simulation of the calibration process and detail analysis of raster distortions occurring in both conventional and counter surface scanning. Moreover, the mode allows to estimate the thermal drift and the creep velocities acting while surface scanning.