The Jandel four point probe can measure sheet resistance and volume (bulk) resistivity of thin films and wafers. The RM3000 control unit can supply constant currents between 10 nA and 99.99 mA, and measure voltages from 0.01 mV to 1250 mV. For sheet resistance measurements the quote range is 1 milliohm/square to 5x10^8 ohms/square. For volume (bulk) resistivity measurements the quoted range is 1 milliohm.cm to 1 x 10^6 ohm.cm. The system also is equipped with a P/N Typing Unit which can determine whether a material is P- or N-type. The provided probe can accommodate wafers up to 10 inches in diameter and ingots up to 10 inches in diameter by 6 inches high.