A Test Structure for Statistical Evaluation of Characteristics Variability in a Very Large Number of MOSFETs

We have proposed and developed a test structure for evaluating electrical characteristics variability of a large number of MOSFETs in very short time using very simple circuit structure. The electrical characteristics such as threshold voltage, subthreshold swings (S-factors, random telegraph signal noise, and so on, can be measured in over one million MOSFETs. This new test structure circuit and results measured by this circuit are very efficient in developing processes, process equipment and device structure which suppress variability.