Simultaneous Analysis of Multi-Variables Effect on the Performance of Multi-Domain MFIS Negative Capacitance Field-Effect Transistors

Guan-You He,Lei-Ying Ying,Ming-Hao Li,Zhi-Wei Zheng,Bao-Ping Zhang,Chun-Hu Cheng,Wei-Dong Liu

doi:10.1109/jeds.2021.3103516

Abstract

With the simulation calibration for negative capacitor considering Landau model and multi-domain (MD) effect, MD MFIS negative capacitance field-effect transistor (NCFET) was thoroughly established for performing the simultaneous analysis of multi-variables (ferroelectric layer thickness ( ${T} _{\mathrm{ FE}}$ ), oxide layer thickness ( ${T} _{\mathrm{ OX}}$ ) and gate length ( ${L} _{\mathrm{ g}}$ )) effect on the device performance. In this study, subthreshold swing ( SS ) and hysteresis properties of MD-MFIS-NCFET were demonstrated by employing TCAD simulation tool. Compared with the previous reported study on single variable effect based on single-domain (SD) NCFET, the simultaneous analysis of multi-variables effect on MD-NCFET enabled to obtain better device performance and generate more comprehensive results. Convincing models were established based on the experimental data by calibration. Demonstration on the basic simulated results including the lowering SS mechanism and the multi-variables effect on MD-NCFET performance was completely presented based on the capacitance matching theory and short channel effect. With the optimal ${T} _{\mathrm{ FE}}$ and ${T} _{\mathrm{ OX}}$ , a trade-off mechanism between the SS and ${L} _{\mathrm{ g}}$ was shown with the consideration of ${L} _{\mathrm{ g}}$ scaling. Noticeable in-depth study in association with the simultaneous analysis of the multi-variables effect was carried out, indicating that the hysteresis-free SS obtained by simultaneous analysis of multi-variables was lower than that obtained by single-variable analysis. Final validation results demonstrate that the optimization proposed in this work by considering the multi-variable effect shows high compatibility with other NCFET devices, providing an instructive strategy for the high-performance NCFET optimization.

Highlights

As the subthreshold swing (SS) of the traditional MOSFETs faces difficulty to fall below 60 mV/dec at room temperature due to the physical limitation of the Boltzmann tyranny [1], Moore’s law is increasingly being challenged
The Si-based MD-MFIS-negative capacitance field-effect transistor (NCFET) built in this work was set with the initial parameters containing Lg (40 nm), junction depth (10 nm), HZO ferroelectric layer (10 nm) and SiO2 insulator layer (3 nm)
It can be seen that the hysteresis exhibits abrupt switching, which is commonly found in TCAD simulation [7], [8]

Summary

INTRODUCTION

As the subthreshold swing (SS) of the traditional MOSFETs faces difficulty to fall below 60 mV/dec at room temperature due to the physical limitation of the Boltzmann tyranny [1], Moore’s law is increasingly being challenged. Most reported studies only discussed single-variable effect on the NCFET devices that based on single-domain (SD) model with the uniform distribution of polarization in ferroelectric layer. Ferroelectric parameters were firstly extracted from the experimental data of the capacitor with negative capacitance effect (NCCAP) by transient NC characteristics fitting. We performed the experiment-based calibration for the NCCAP with the TCAD tool by fitting transient model with experiment data [18] to extract the ferroelectric parameters. Base on the calibration of our simulation for the NCCAP and nonFeFET, the optimization of the MD-NCFET with the MFIS stack was investigated subsequently

RESULTS AND DISCUSSION

VALIDATION

CONCLUSION