Multibit Ferroelectric FET Based on Nonidentical Double HfZrO2 for High-Density Nonvolatile Memory

A double-HZO (HfZrO2) FeFET (ferroelectric FET) with nonidentical ferroelectric thicknesses is experimentally demonstrated with as low as vertical bar V-P/E vertical bar = 5 V, 2-bit endurance > 10(5) cycles and retention > 10 4 s. Inserting an insulator to separate the ferroelectric layers and avoid the monoclinic formation of a thick Fe-HZO (ferroelectric-HZO) is a useful method to enhance the MW (memory window) for MLC (multilevel cell) applications. Double-HZO has a lower ER (error rate) and shows a 600X improvement compared to single-HZO. The stacked HZO FeFET has potential as an MLC for high-density NVM (nonvolatile memory) applications.

Automated summary

A double-HfZrO2 (HZO) FeFET with nonidentical ferroelectric thicknesses demonstrated lower drive voltage, longer endurance, and retention time. Inserting an insulator to separate the ferroelectric layers improved the memory window for multilevel cell applications. Double-HZO showed lower error rate and 600 times improvement compared to single-HZO, making it a potential MLC for high-density NVM applications.