Abstract
Determining the thickness of two‐dimensional (2D) materials accurately and reliably is highly necessary for multiple investigations, but at the same time it can be quite complex. Most studies in this field measure a topographic map at the edge of the 2D material using an atomic force microscope (AFM), and plot a single‐line cross‐section using the software of the AFM. However, this method is highly inaccurate and can result in high relative errors due to surface roughness and line‐to‐line variability. This is even more important in ultrathin (<4 nm) 2D materials grown by chemical vapor deposition, as these exhibit a larger surface roughness (compared to mechanically exfoliated) due to the high density of local defects. Here it is shown that the thickness of ultrathin 2D materials can be determined statistically with high accuracy and reliability in a very easy way by plotting the histogram height plot. Using this method should enhance the reliability of investigations and research papers in the field of 2D materials.
The thickness of ultrathin two‐dimensional materials can be determined statistically with high accuracy and reliability by measuring topographic maps with atomic force microscopy at edges and potting the histogram height: the accurate height is the distance between the two peaks. This method is much more accurate than taking cross‐sections of the map at random locations, which can have >20% errors.