Work Function Adjustment by Using Dipole Engineering for TaN-Al(2)O(3)-Si(3)N(4)-HfSiO(x)-Silicon Nonvolatile Memory

This paper presents a novel TaN-Al(2)O(3)-HfSiO(x)-SiO(2)-silicon (TAHOS) nonvolatile memory (NVM) design with dipole engineering at the HfSiO(x)/SiO(2) interface. The threshold voltage shift achieved by using dipole engineering could enable work function adjustment for NVM devices. The dipole layer at the tunnel oxide–charge storage layer interface increases the programming speed and provides satisfactory retention. This NVM device has a high program/erase (P/E) speed; a 2-V memory window can be achieved by applying 16 V for 10 μs. Regarding high-temperature retention characteristics, 62% of the initial memory window was maintained after 10(3) P/E-cycle stress in a 10-year simulation. This paper discusses the performance improvement enabled by using dipole layer engineering in the TAHOS NVM.