In-situ electrical characterization

An in-situ electrical characterization technique was developed to study details of the deformation behavior during indentation.  This technique is especially suited to studies of the phase transformation of Si due to the nature of the transformations in this material (on loading Si transforms from a semiconductor to a metal).  The experimental arrangement involves the measurement of current flow through a reverse-biased Schottky diode and exploits a sharp transition from a Schottky to an Ohmic contact that accompanies the formation of the metallic Si-II phase directly under the indenter. 

This electrical technique is particularly sensitive to the nature and extent of the local Si-I to Si-II phase transformation and allows such changes to be directly correlated with features in nanoindentation load-unload curves as is shown below.

Further details of the in-situ electrical characterisation of crystalline Si during nanoindentation can be found here: Physical Review B 67, 085205 (2003).