A new automated methodology for random telegraph signal identification and characterization: a case study on phase change memory arrays

We present a new method for the statistical analysis of random telegraph signals. Simulations show the good features of the method which is a powerful tool for evaluating the impact of RTS on performance and reliability of electron devices. Its application to phase change memories will be discussed in order to successfully analyze a new RTS phenomenon observed in the SET state during cycling. The physical nature of the phenomenon has been related to the random presence of an extra parasitic crystal (PC) path in the active volume of the chalcogenide material. The large current densities flowing during the SET operations can induce the PC formation, whereas the high temperature and the short quench time of the RESET operation are able to revert the PC to the amorphous state. Finally, the analysis shows that PC are correlated with the anomalous tail of the RESET distribution.