
185Evaluation of Silicon Wafers
two-dimensional stress maps through polariscopy—a nondestructive, highly sensitive,
and quantitative mapping technique for residual strains in semiconductor process–bound
wafers [77]. Recently, a noncontact sheet resistance and leakage current measurement tech-
nique has been developed. The big advantage with this is that even process-bound wafers
can be analyzed for any of the issues listed earlier. For a silicon wafer, only the electrical
parameters are important, along with dopant and defect evaluations.
Stefani et al. [34] introduced a computer-controlled eddy current system for in situ moni-
toring of CZ sil ...