Verification of Carrier Density profiles Derived From Spreading Resistance Measurements by Comparing Measured and Calculated Sheet Resistance Values

摘要

In the past, resistivity and carrier density profiles derived from spreading resistance measurements have been satisfactorily verified by comparing a doped layer's measured sheet resistance, rou sup s, with a sheet resistance value calculated from the on-bevel resistivity profile. However, this verification process has been found to fail in the case of ultrashallow source/drain implants. This paper examines all possible sources of the discrepanceybetween rou sub s-measured and rou sub s-calculated, and concludes that the lack of a sheet resistance edge correction in the standared multilayer SRP analysis is the dominant factor. The paper also discusses the role played by bevel surface damage, on-bevel carrier diffusion, and variations in carrier mobility in high dopant density regions.