Materials Development Corporation offers the complete line of Four Point Probe systems from AIT. Systems are available to measue up to 12" diameter (300 mm) wafers as well as specialty systems for Photovoltaic wafers and substrates. For more information on these systems, contact MDC. The model CMT-SR2000N is by far the most popular of the AMT line. It is an easy-to-use, fully automatic, four-point probe system for measuring sheet resistance and resistivity of semiconductor wafers with diameters from 50 mm to 200 mm. The system can be used alone or fully automated under PC control.