TNSiC series Stepped Silicon Carbide Sample

Calibration procedure

To calibrate AFM scanner in the Z axis, the following operations should be performed:

• Place the SiC-0.75 or 1.5nm calibration sample on the flat horizontal working area under the AFM probe.
• Approach the AFM probe to the sample surface and make a topography scan in the height measuring mode using a scan size of about 5 µm (Fig.1). Make sure that there is no dust on the surface, and then make further measurements with a scan size of 1.5 µm.
• After obtaining good quality AFM-image of the surface area with several steps, use the software filter to flatten image so that every single step becomes horizontal (Fig. 2). Choose an area on AFM-image to measure the height spectrum by using the AFM analysis software. For the height spectrum, the area with maximum number of steps will give better statistics. After obtaining the height spectrum with peaks corresponding to each step, measure the interpeak distance. Note that distances between neighbouring peaks may vary a little (see Fig.3), so it is useful to average distances between peaks by measuring distance between far standing peaks and dividing the measured value by the number of included interpeak distances (A-A on Fig. 3). Change the scanner calibration parameters until the average interpeak distance becomes 0.75 nm or 1.5 nm depending on the version of the sample (see product options).