Abstract
The four-ring probe method which was devised as a method of measuring resistivity is described. This method is applicable to the system consisting of a circular disk sample and a four-ring probe array. The resistivity correction factor (RCF), which is necessary for correcting data measured by means of the four-ring probe method and for obtaining the resistivity of the sample, is derived analytically. The properties of the RCF are discussed on the basis of the theoretical analysis. It is demonstrated by the experimental results that (i) the RCF corrects data accurately, (ii) it is insensitive to the shape of the sample and the measurement position as long as the thickness of the sample is less than the probe spacing, and (iii) the four-ring probe method is compatible with the four-point probe method.