Boost of orthorhombic population with amorphous SiO2interfacial layer-a DFT study
Journal
Semiconductor Science and Technology
Journal Volume
37
Journal Issue
5
Date Issued
2022
Author(s)
Chen Y.-W
Abstract
Via the density functional theory, the phase diagrams of HZO thin film in MFM (M = TiN, F = HZO) and MFI (I = α-SiO2) structures are constructed with dependences on grain size and temperature. In both MFM and MFI, the region for orthorhombic phase (o-phase) in phase diagram grows when HZO thickness gets thinner. Comparing to MFM, HZO/α-SiO2 interface in MFI suppresses the growth of tetragonal phase (t-phase) to the region of very small grain size ??.2 nm. The simulation results agree with the experimental observation by Cheema et al, that the enhanced FE property was obtained in a MFIS (S = silicon) device with ultrathin HZO film (<2 nm). Simulation model indicates more chemical bonds forming between HZO and α-SiO2 interface could stabilize o-phase to greatly enhance the FE property in a MFIS device. © 2022 IOP Publishing Ltd.
Subjects
anti-ferroelectric (AFE); ferroelectric (FE); interfacial energy
Other Subjects
Density functional theory; Grain size and shape; Phase diagrams; Silica; Silicon oxides; Anti ferroelectrics; Anti-ferroelectric; Density-functional-theory; DFT study; Ferroelectric; Ferroelectric property; Grainsize; Interfacial layer; Orthorhombic phase; Thin-films; Ferroelectricity
Type
journal article