Modern techniques of semiconductor physical failure analysis are effective at revealing physical defects and device material composition, however, dopant profiles/ concentrations are not easily determined since these materials are in trace concentrations. Therefore, defects related to dopants are often referred to as invisible defects. New techniques have been incorporated into failure analysis to reveal the invisible defects resulting from electrical carriers (via SCM/SSRM) and physical doping profile (via STEM/EDS) in nm-scale dimension. Using nanoprobing analysis, simulation for electrical modeling, along with EDS and SCM for physical profiling, we have a great opportunity to uncover abnormal doping issues allowing completion of the failure analysis and the execution of corrective actions.

Owing to the advancing progress of electrical measurements using SEM (Scanning Electron Microscope) or AFM (Atomic Force Microscope) based nanoprober systems on nanoscale devices in the modern semiconductor laboratory, we already have the capability to apply DC sweep for quasi-static I-V (Current-Voltage), high speed pulsing waveform for the dynamic I-V, and AC imposed for C-V (Capacitance-Voltage) analysis to the MOS devices. The available frequency is up to 100MHz at the current techniques. The specification of pulsed falling/rising time is around 10 -1 ns and the measurable capacitance can be available down to 50aF, for the nano-dimension down to 14nm. The mechanisms of dynamic applications are somewhat deeper than quasi-static current-voltage analysis. Regarding the operation, it is complicated for pulsing function but much easy for C-V. The effective FA (Failure Analysis) applications include the detection of resistive gate and analysis for abnormal channel doping issue.

The Nanoprobing technique has become a popular tool for the Failure Analysis. This paper tries to establish the fundamental postulates for the following improvement of the technique. After description of the postulates, the application to missing or blocked LDD is claimed. Meanwhile, the following strategy of post-Nanoprobing is discussed by the case of missing LDD and for general conditions.