Study of phase change memory cell with inserting buffer layer

TiO2 and HfO2 with different electrical conductivity were used as buffer layer for phase change memory (PCRAM) cell, where Si-Sb-Te alloy was used as storage medium in the PCRAM cell. The electrical properties of the cells with and without buffer layer were compared through resistance-voltage measurements. It is found that the PCRAM cell with both TiO2 and HfO2 buffer layer has relative low operation voltage. Furthermore, the inserting TiO2 buffer layer can also improve the device stability. It is considered that buffer layer with suitable electrical conductivity is needed for the PCRAM cell, especially in future high density storage. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)