A simple investigation of several samples using a scanning tunneling microscope

A variety of samples, namely HOPG (highly ordered pyrolytic graphite), gold (111), a nanogrid and tantalum disulfide (TaS2) were scanned using a scanning tunneling microscope (STM) and analysed. The lattice constant of graphite was found to be (0.141 ± 0.038) nm which is in agreement with the literature value. Scans of the other samples provided good images which were analysed numerically in a variety of ways. A nanogrid (a manufactured sample with a known structure on the nanoscale) was scanned and used to investigate the calibration of the STM with some interesting results; the piezo actuators that move the tip suffer from hysteresis and thus only delivered accurate values at small scan ranges.