Towards the Ultimate Memory Window Enhancement of Nanoscale Hf0.5Zr0.5O2 FeFETs with Interface and Strain Engineering

In this work, HfO₂/Ozone SiO₂ interfacial layer (IL) and ZnS:SiO2 (ZSO) liner stressor are novelly integrated with nanoscale Hf_0.5Zr_0.5O₂ (HZO) FeFETs for the memory window (MW) enhancement. With the HfO₂/Ozone SiO₂ IL engineering, the MW of the HZO FeFET reaches as high as 3.5 V at an effective channel length of 150 nm. Both tensile and compressive liner stressors are integrated with the HZO FeFETs to explore their impact on the FE HZO layer, read speed and the MW of FeFETs. Tensile ZSO stressor exhibits a MW enhancement of 40% for long channel FeFETs and the enhancement increases further as the channel length scales, demonstrating its great potential and scalability for MW enhancement of HZO FeFETs.