Surface potential mapping of biased pn junction with kelvin probe force microscopy: application to cross-section devices

Kelvin probe force microscopy (KPFM) opens up a new field of applications as advanced technique to characterize crosssectional electric field as well as distribution of surface potential of functioning integrated circuits. Original sample preparation and connecting method allowing sharp observations on the circuit cross-section with conservation of circuit power supplying is presented. This device preparation method combined with KPFM is an illustration of innovative technique which allows imaging of contact potential difference and topography of tested device structure. Build-in electric field is derived from surface potential and allows to locate the electric junction