Programming Characteristics of Two-Bit Sonos Type Flash Memory Using High-K Dielectric Material

In this paper, programming characteristics of two- bit SONOS (silicon-oxide-nitride-oxide-silicon) with high-k dielectric material is analysed. Two bit is used for increment of storage density instead of a single cell. Hafnium Oxide has good programming characteristics, so in this design Hafnium Oxide as high-k material is used. This material is responsible for charge trap in the device. In this paper, comparison of dual-bit SONOS using Si₃N₄ material with dual bit using HfO₂ as charge trap layer is done. HfO₂ has higher leakage than Si₃N₄ and data retention behaviour is also poor. In this design sentaurus Tcad tool in 40nm technology is used.