Joule expansion imaging techniques on microlectronic devices

We have studied the electrically induced off-plane surface displacement on two microelectronic devices using scanning Joule expansion microscopy (SJEM). We present the experimental method and surface displacement results. We show that they can be successfully compared with surface displacement images obtained using an optical interferometry method. We also present thermal images using scanning thermal microscopy (SThM) technique to underline that SJEM is more adapted to higher frequency measurements. The performances of the three methods are compared.