High-resolution and site-specific SSRM on S/D engineering

Abstract

Recently, we reported significantly improved spatial resolution in scanning spreading resistance microscopy (SSRM) by measuring in a vacuum. In this work, we demonstrate the 1-nm-spatial resolution of SSRM on pn junction delineation by comparing with three-dimensional device simulation. A five-order dynamic range of carrier concentration is also confirmed on staircase sample. A systematic comparison between pFETs/nFETs on (110) and (100) substrates has been carried out with SSRM. The S/D of (110) pFETs shows less lateral distribution than that of (100), strongly indicating 2D-channeling effect of boron ion implantation. We also succeeded in a new sample-making method by fully FIB pick up, enabling site-specific SSRM characteristics for failure analysis and for further scaled devices.