Rapid Characterization of Threshold Voltage Fluctuation in MOS Devices

We present a technique for fast characterization of random threshold voltage variation in MOS devices. Our Vtau scatter characterization method measures threshold voltage shift by monitoring the change in gate-to-source voltage VGS for a fixed drain current IDs and drain-to-source voltage VDS. We measure VGS variation for a large set of devices arranged in an individually addressable array and report results of Vtau scatter measurement from a test chip in a 65 nm SOI CMOS process. We also measure and report the magnitude of local device current mismatch caused by the Vtau fluctuation.