Abstract: Ultra-shallow Si p+n junctions formed by plasma doping are characterized by electrochemical capacitance-voltage(ECV).By comparing ECV results with secondary ion mass spectroscopy(SIMS) results,it is found that the dopant concentration profiles in the heavily-doped p+ layer as well as junction depths measured by ECV are in good agreement with those measured by SIMS.But the ECV measurement of the dopant concentration in the lightly doped n-type substrate underneath is significantly influenced by the upper heavily-doped layer.The ECV technique is also easy to control and reproduce.The ECV results of ultra-shallow junctions (USJ) formed by plasma doping followed by different annealing processes show that ECV is capable of reliably characterizing a Si USJ with a junction depth as low as 10nm,and dopant concentration up to 1E21cm-3.Its depth resolution can reach as low as 1nm.Therefore it shows great potential in applications for characterizing USJ in sub-65nm technology node CMOS devices.

Key words: electrochemical capacitance-voltage, ultra-shallow junction, dopant concentration