Development and Technical Issues on 2D-Carrier Profiling of Silicon Devices by Scanning Spreading Resistance Microscopy (SSRM) with 1 nm spatial resolution

Abstract

  Scanning spreading resistance microscopy (SSRM) is a powerful technique for 2D-carrier profiling of silicon devices. We developed high spatial resolution SSRM by measuring in a high vacuum and achieved 1 nm spatial resolution. We also confirmed wide dynamic range of measuring concentration of 10¹⁵ through 10²⁰ cm^-3. In this paper, we demonstrate experimental aspects and procedures of SSRM measurement, and applications to scaled CMOSFETs. SSRM in a high vacuum is shown to have high potential for carrier analysis of future devices. Technical issues affecting reproducibility and quantitative analysis of carrier concentration are also discussed.