These 2-D holographic array standards for simultaneous calibration of X and Y axes have unique characteristics that make them easy to use for AFM, STM, Auger, FIB and SEM.
There are two pitch sizes available:
The 144nm pitch, two dimensional array is accurate to ±1nm and is suitable for SEM and AFM calibrations. The pattern covers the entire chip enabling thousands of measurements to be made without revisiting the same scan area. The surface comprises aluminium ‘bumps’ on silicon. The bump height is approximately 90nm and width 75nm (not calibrated).
For SEM the 144nm standard works well at all accelerating voltages.
For AFM it can be used in contact, intermittent contact (TappingMode™) and other modes, with image sizes from 250nm to 10mm. For AFM the2-D standard is available unmounted or can be mounted on 12mm steel discs. The pattern is durable and allows for extended scanning in contact mode, which means that calibration and measurements are faster.
Each standard is individually measured in comparison with a similar specimen calibrated at the German PTB (Physikalisch-Technische Bundesanstalt). The uncertainty of a single pitch is typically ±1.4nm.