研究目的
To study the performance of biaxially strained ferroelectric-based negative capacitance FETs (NCFETs) using device simulations, focusing on the effects of strain on materials like PZT and HfO2.
研究成果
Biaxial strain significantly enhances the performance of PZT-based NCFETs, particularly under compressive strain, improving subthreshold swing, ON-state current, and enabling large negative differential resistance. HfO2-based NCFETs are less sensitive to strain, with optimal performance in unstrained conditions. Appropriate strain application can achieve zero drain-induced barrier lowering in PZT-based devices, highlighting the potential for strain engineering in optimizing NCFET performance.
研究不足
The study is based on computational simulations and does not involve experimental validation. The effects are analyzed for specific materials (PZT and HfO2) and strain ranges, which may not generalize to other ferroelectric materials or different strain conditions. The ballistic transport regime assumption might not fully capture real-world device behaviors.
1：Experimental Design and Method Selection:
The study uses computational simulations based on density functional theory (DFT) and device modeling. The first-principles method is employed to apply biaxial strain and extract Landau parameters. Device simulations involve solving the non-equilibrium Green's function equation with the Poisson equation in the ballistic transport regime, and modeling the ferroelectric layer using the Landau-Khalatnikov equation.
2：Sample Selection and Data Sources:
The ferroelectric materials used are PbZr0.5Ti0.5O3 (PZT) and HfO2. Strain is applied biaxially within a range of -4% to +4% on fully relaxed structures derived from DFT calculations.
3：5Ti5O3 (PZT) and HfOStrain is applied biaxially within a range of -4% to +4% on fully relaxed structures derived from DFT calculations.
List of Experimental Equipment and Materials:
3. List of Experimental Equipment and Materials: Computational tools include the OpenMX package for DFT calculations, and an in-house tool for device simulations. Materials include PZT and HfO2 with specified lattice constants.
4：Experimental Procedures and Operational Workflow:
The simulation procedure consists of two parts: extracting Landau parameters from DFT results (Part A), and conducting device modeling and transport calculations (Part B). Biaxial strain is imposed, and parameters are extracted and used in NCFET simulations.
5：Data Analysis Methods:
Data analysis involves fitting free energy curves to extract Landau parameters, and comparing performance metrics such as subthreshold swing, ON-state current, drain-induced barrier lowering, and negative differential resistance for different strain conditions.
独家科研数据包，助您复现前沿成果，加速创新突破
获取完整内容
