The scanning tunneling microscope (STM) and the atomic force microscope (AFM), both capable of visualizing and manipulating individual atoms, are the cornerstones of nanoscience and nanotechnology today. The inventors of STM, Gerd Binnig and Heinrich Rohrer, were awarded with the Nobel Prize of physics in 1986. Both microscopes are based on mechanically scanning an atomically sharp tip over a sample surface, with quantum-mechanical tunneling or atomic forces between the tip and the atoms on the sample as the measurable quantities. This book presents the principles of STM and AFM, and the experimental details. Part I presents the principles from a unified point of view: the Bardeen theory of tunneling phenomenon, and the Herring-Landau theory of covalent-bond force. The similarity between those two theories, both rooted from the Heisenberg-Pauling concept of quantum-mechanical resonance, points to the equivalence of tunneling and covalent-bond force. The Tersoff-Hamann model of STM is presented, including the original derivation. The mechanisms of atomic-scale imaging of both STM and AFM are discussed. Part II presents the instrumentation and experimental techniques of STM and AFM, including piezoelectric scanners, vibration isolation, electronics and control, mechanical design, tip treatment and characterization, scanning tunneling spectroscopy, and atomic force detection techniques. Part II ends with illustrative applications of STM and AFM in various fields of research and technology.

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We present a novel quartz cantilever for frequency-modulation atomic force microscopy (FM-AFM) which has three electrodes: an actuating electrode, a sensing electrode, and a ground electrode. By applying an ac signal on the actuating electrode, the cantilever is set to vibrate. If the frequency of actuation voltage closely matches one of the characteristic frequencies of the cantilever, a sharp resonance should be observed. The vibration of the cantilever in turn generates a current on the sensing electrode. The arrangement of the electrodes is such that the cross-talk capacitance between the actuating electrode and the sensing electrode is less than 10(-16) F, thus the direct coupling is negligible. To verify the principle, a number of samples were made. Direct measurements with a Nanosurf easyPPL controller and detector showed that for each cantilever, one or more vibrational modes can be excited and detected. Using classical theory of elasticity, it is shown that such novel cantilevers with proper dimensions can provide optimized performance and sensitivity in FM-AFM with very simple electronics.