VDI/VDE 2656 BLATT 1
Determination of geometrical quantities by using of Scanning Probe Microscopes - Calibration of measurement systems
|Publication Date:||1 June 2008|
|ICS Code (Linear and angular measurements in general):||17.040.01|
|ICS Code (Mechanical testing):||19.060|
This guideline is restricted to scanning probe microscopes and their calibration. A scanning probe microscope is a serially operating measuring device which uses a probe of adequate fineness to trace the surface of the object to be measured exploiting a local physical interaction (such as the quantum-mechanical tunnel effect, interatomic or intermolecular forces, evanescent modes of the electromagnetic field) with the probe and the object to be measured being displaced in relation to one another in a plane (hereinafter referred to as the x-y-plane) according to a defined pattern, while the signal of the interaction is recorded and can be used to control the distance between probe and object to be measured. In this guideline signals are considered which are used for the determination of the topography (hereinafter called "z-signal").
The guideline covers the verification of the device characteristics necessary for the measurement of geometrical measurands, and the calibration of the axes of motion (x, y, z), i. e. the traceability to the unit of length via measurement on traceable lateral and step height standards (Figure 2).
With the implementation of this guideline the following objectives are pursued:
• increase in the comparability of measurements of geometrical quantities using scanning probe microscopes by traceability to the unit of length
• definition of minimum requirements for the calibration process and the conditions of acceptance
• ascertainment of the calibratability (assignment to calibratability categories)
• fixing of the scope of a calibration (conditions of measurement and environments, ranges of measurement, temporal stability, transferability)
• provision of a model according to GUM to calculate the uncertainty for simple geometrical quantities in measurements using a scanning probe microscope (see Section 8)
• definition of the requirements for a result report