Ultra-Low Constant Current Sources are needed when the sample resistance, either inherently or due to contact resistances, is large. These include the resistivity measurement of silicon wafers or high resistivity film deposits. Large values of the sample resistance make the measurement prone to noise pick-up from the mains and elsewhere. This is one of the most significant problems of high resistance measurement.
Open Circuit Voltage : 15V
Current Range : 0-2μA, 0-20μA, 0-200μA, 0-2mA
Minimum : 1nA at 0-2μA range
Accuracy : ± 0.25% of the reading ± 1 digit
Display : 31⁄2 digit, 7 segment LCD with autopolarity and decimal
Load Regulation : 0.05% for 0 to full load
Power : 3 x 9V batteries