Inaccuracies in contact resistivity from the Cox–Strack method: A review

Recently, the Cox–Strack method for contact resistivity determination is increasingly used in the context of photovoltaic cell engineering. This document reviews the literature published in the period 2017–2021 containing Cox–Strack measurement results. As the Cox–Strack method is error-prone, we analyze this literature on the possible inaccuracies that may arise due to (1) approximations by Cox and Strack, (2) the choice of contact diameters, and (3) resistive coatings. On the basis of our findings, more than half of the 93 reviewed articles may need additional analysis for an accurate quantification of the lower reported contact resistance values. The article concludes with recommendations for an improved Cox–Strack methodology.