Scalpel soft retrace scanning spreading resistance microscopy for 3D-carrier profiling in sub-10nm WFIN FinFET

Abstract

Site-specific real three-dimensional (3D) carrier profiling in sub-10nm WFIN devices is demonstrated for the first time. Extension-gate overlap, active dopant concentration and distribution inside extensions and epi source/drain are observed with 1 nm-spatial resolution along X, Y and Z-directions. Using this new technique providing full 3D-carrier mapping we analyzed different processing flows for sub-10nm fin width FinFETs, identified possible failure mechanisms, and demonstrated the direct link between improved performance and 3D-carrier distribution at the nm-scale.