Electrochemical Capacitance Voltage Profiling (ECV-Profiling) is a valuable and handy tool for semiconductor analysis.
The following table compares its benefits to
Hall, SIMS (Secondary Ion Mass Spectroscopy) and SRP (Sheet Resistance Profiling):

 
Application requirement

Hall

SIMS

SRP

ECV

Monitor the doping concentration

Monitor the concentration of electrically activated dopants

Monitor the doping type (n or p)

Monitor the crystalline quality of the sample

Easy sample preparation

Easy equipment preparation (no calibration or standard samples required)

Easy contact preparation

Substrate may be conductive

Thickness of the epi layer may be unknown

Depth Profile may be measured

Depth resolution in the 1nm range possible

Several layers may be resolved

A broad range of semiconductors may be measured

Concentrations below 1014 cm-3  may be measured *)

Wafer topography may be analyzed

Measurement without prior mechanical or lithographic preprocessing

Photo-Electro-Chemical (PEC) etching may be evaluated

The surface may be etched/ passivated on start of the measurement

*) SIMS may measure lower concentrations for certain dopant types and semiconductor materials, but for dopants as important as Si in GaN it starts to fail already at a concentration range of below 1016 cm-3.

 

The Wafer Profiler CVP21 is the superior solution for Electrochemical Capacitance Voltage Profiling.