Charge Loss Mechanisms of Nitride-Based Charge Trap Flash Memory Devices

Technology scaling challenges for flash memory beyond 30 nm exacerbated as device fundamental limits are fast approaching. Nitride-based charge trap flash (CTF) is one of the most viable alternatives to eclipse floating gate flash in the market by leveraging the existing materials as compared with other exploratory nonvolatile memory devices. However, postcycled threshold voltage instability in the form of charge loss (CL) mechanisms remains as critical reliability challenges to further improve long-term data retention performance. This paper focuses on long-term data retention reliability issues with an emphasis on major CL mechanisms of nitride-based CTF memory. It encompasses comprehensive reviews and discussions on major CL mechanisms due to intrinsic and extrinsic causes. This paper would serve as a good reference for the future development of nitride-based CTF memory.