Quantitative atomic force measurement with a quartz tuning fork

The authors demonstrate a simple yet robust method for quantitative measurement of dynamic atomic force using the quartz tuning fork for both electrically driven mode and mechanically driven mode. It is shown that both modes can be made fully equivalent and also allow accurate force measurement. The quartz tuning fork is now expected to be widely employed as a quantitative force measurement probe in addition to its capability to surface image in the atomic scale. (C) 2007 American Institute of Physics.