Low frequency noise in phase change materials

Abstract

Low frequency noise (LFN) is particularly well-adapted for studies of phase change memory cells as it is generated in the cells' amorphous volume alone. The latter is known to have a very high concentration of localized traps and the charge transport proceeds via hopping in a random network of traps. LFN is proposed to be generated by variation in the configuration of the traps' structure. The spectral power density of LFN (i) is of the 1/f type, (ii) varies as the cell current square, (iii) is inversely proportional to the cell thickness. Some results of the LFN dependence on the cells' resetting conditions and structure are also discussed.