Mechanism and Performance Verification of Channel-Hot-Electron Induced Hot-Hole Injection-Based High-Speed Erasure for Split-Gate Charge-Trapping Flash Memory

The mechanism of the novel channel-hot-electron induced hot-hole (CHH) injection for high-speed erasure (ERS) in the split-gate charge trapping flash (CTF) cell is systematically investigated. In this scheme, hot holes generated by impact ionization of channel hot electrons exhibit approximately three times higher density and a significantly wider spatial distribution compared to band-to-band tunneling-induced hot-hole (BBHH) ERS. This enhances the hole injection to the charge trapping layer and the trapped hole-electron neutralization, leading to more efficient ERS. In addition, it is experimentally verified that the CHH mechanism enables approximately$100\times $faster erasing speed (~0.1 ms) than BBHH, while also achieving better endurance ($10^{{5}}$) and retention (ten years at$175~^{\circ }$C). These advantages make it ideal for high-speed and highly reliable nonvolatile memory (NVM) applications.