Dopant profile inspection is one of the focused ion beam (FIB) physical analysis applications. This paper presents a technique for characterizing P-V dopant regions in silicon by using a FIB methodology. This technique builds on published work for backside FIB navigation, in which n-well contrast is observed. The paper demonstrates that the technique can distinguish both n- and p-type dopant regions. The capability for imaging real sample dopant regions on current fabricated devices is also demonstrated. SEM DC and FIB DC are complementary methodologies for the inspection of dopants. The advantage of the SEM DC method is high resolution and the advantage of FIB DC methodology is high contrast, especially evident in a deep N-well region.

The techniques of doping profile inspection, such as SEM (Scanning Electron Microscope) dopant contrast, SEM wet stain and SCM (Scanning Capacitance Microscope) have been widely used in failure analysis for implant root causes identification. The applications of real FA (Failure analysis) cases and advantages/disadvantages will be discussed and demonstrated in this paper. To sum up, SEM dopant contrast is the most convenient method for doping profile inspection, and SCM is the best method for low doping profile observation.