Crystal Filter-Mediated Grain Alignment in Poly-Si Thin-Film Transistors for Next-Generation Ferroelectric Memory Devices

Hafnia-based ferroelectric thin-film transistors (FeTFTs) hold promise for next-generation memory applications like three-dimensional (3D) NAND flash memory, owing to their low power and high-speed operation. However, the utilization of polycrystalline Si (poly-Si) channels imposes limitations on the on-current of the device due to its low mobility. Consequently, alternative channel materials and diverse device engineering methods are being explored. In this study, we fabricated a FeTFT utilizing a poly-Si channel with aligned grains, achieved through the crystal-filtered (CF) metal-induced lateral crystallization method. The CF poly-Si channel exhibited an increase in on-current compared to conventional poly-Si channels. Additionally, the FeTFT employing CF poly-Si demonstrated a memory window of 3.2 V and a switching speed of 50 ns. This study represents a significant advancement in the field of FeTFTs and holds potential for application in next-generation electronic devices, particularly in 3D NAND flash memory, display, and neuromorphic device applications.