A Spreading Resistance Technique for Resistivity Measurements on Silicon

A technique for determining local silicon resistivity from the measured spreading resistance associated with a metal to semiconductor, small‐area pressure contact is described. The major problems encountered in earlier attempts to derive quantitative resistivity data from small area pressure contacts on silicon have been circumvented by making the measurements at bias levels of a few millivolts and by using a particular osmium‐tipped probe arrangement to provide contact reproducibility. The method provides a three‐dimensional spatial resolution in resistivity measurements on silicon on the order of 1μ, and, using a calibration curve determined for a particular silicon surface finish, yields an experimental reproducibility ≤15% for sample resistivities in the range . Several examples of the application of the technique to problems of current interest in silicon technology are given.