Application of electron holography to analysis of submicron structures

Importance of effects of charging and sample thickness variation across depletion region is discussed using one-dimensional p-n junction in bulk Si and silicon-on-insulator (SOI) structures prepared by mechanical polishing. It is shown that good correlation between results of electron holography and secondary ion mass spectroscopy can be achieved without consideration of “dead layers.” Analysis of laser annealed n-type field-effect transistor (n-FET) devices in SOI structures showed that laser annealing does not cause lateral dopant diffusion of arsenic to resolution of electron holography. It is demonstrated that junction overlap can be achieved with “laser-only” integration scheme. Examples are given on how electron holography can provide insight into integration scheme for development of a p-FET device with embedded SiGe source/drain regions and evaluation of effect of proximity of shallow trench isolation on dopant depletion.