Silicon and Its Vital Role in The Evolution of Scanning Probe Microscopy

Abstract

Silicon has played an important role in the development of scanning probe microscopes. The 7 × 7 reconstruction of silicon has been a challenge for surface scientists for more than two decades. In 1983, the scanning tunneling microscope (STM), invented by Gerd Binnig and Heinrich Rohrer, yielded the first atomically resolved image of Si (111) (7×7) in real space. The information contained in this data has helped to develop the dimer—adatom—stacking-fault model of Takayanagi et al. The Si (111) (7×7) surface has been considered a touchstone for a different scanning probe microscope: the atomic force microscope (AFM). While STM images of the Si (111) (7×7) surface were achieved a year after the introduction of the STM, the AFM took almost a decade to meet the challenge of this excitingly complicated surface. While the initial AFM data did not give new information about the silicon surface, the quest for imaging this complicated surface has served as a driving force for perfecting the AFM. The resolution of the AFM has been increased and the Si (111) (7×7) surface is now a standard test sample for the AFM. Because the surface is known well, it can be used to learn more about the three-dimensional structure of the probe tip of the microscope. Silicon is both an exciting object of study and an important material for scanning probe microscopes.