Nanoindentation and picoindentation measurements using a capacitive transducer system in atomic force microscopy

Abstract
An indentation system is developed to directly apply loads ranging from 1μN to 10 mN and to make load–displacement measurements with subnanometre indentation depth capability. This system is used here in conjunction with a commercial atomic force microscope to provide in-situ imaging. A three-sided pyramidal (Berkovich) diamond tip has been used to obtain a load–displacement curve with residual depths of the order of 1 nm. The load–displacement data have been used to obtain indentation hardness and Young's modulus of elasticity for singlecrystal silicon and GaAs. Hardness on the nanoscales is found to be higher than that on the microscale. Ceramics exhibit significant plasticity and creep on the nanoscale.