Abstract: As a multigate device, the multiple‐state electrostatically formed nanowire transistor (MSET) exhibits a rather complex characteristic on account of the coupling between each of its two adjacent terminals. The MSET has shown promise across a steadily growing range of applications and integrated circuit components. However, an analytical model of the MSET has not been formulated. The objective of this work was to develop practical DC and transient models of the MSET. The modeling approach comprises two stages: the first stage consists of a bottom‐up derivation of the I–V characteristics from the fundamental physical level using the physical processes within the device to derive equations that describe its steady‐state behavior; the second stage proposes a set of analytical equations more applicable to simulation environments. A transient model that considers device parasitic capacitance is also established. The models are validated against robust model simulations in TCAD Sentaurus and Cadence Virtuoso.
[2] Ciou, Jhang-Yan, Sourav De, Wallace Lin, Yao-Jen Lee, and Darsen Lu. "Analytical Modelling of Ferroelectricity Instigated Enhanced Electrostatic Control in Short-Channel FinFETs." arXiv e-prints (2020): arXiv-2007.
Abstract: This study simulated negative-capacitance double gate FinFETs with channel lengths ranging from 25nm to 100nm using TCAD. The results show that negative capacitance significantly reduces subthreshold swing as well as drain induced barrier lowering effects. The improvement is found to be significantly more prominent for short channel devices than long ones, which demonstrates the tremendous advantage of negative capacitance gate stack for scaled MOSFETs. A compact analytical formulation is developed to quantify sub-threshold swing improvement for short channel devices.
Fig: (a) Three-dimensional NC FinFET structure studied insimulation. (b) List of nominal device parameters used in TCAD simulation.
[3] Ahmed, Sheikh Z., Samiran Ganguly, Yuan Yuan, Jiyuan Zheng, Yaohua Tan, Joe C. Campbell, and Avik W. Ghosh. "A Physics Based Multiscale Compact Model of pin Avalanche Photodiodes." arXiv preprint arXiv:2102.04647 (2021).
Abstract: III-V material based digital alloy Avalanche Photodiodes (APDs) have recently been found to exhibit low noise similar to Silicon APDs. The III-V materials can be chosen to operate at any wavelength in the infrared spectrum. In this work, we present a physics-based SPICE compatible compact model for APDs built from parameters extracted from an Environment-Dependent Tight Binding (EDTB) model calibrated to ab-initio Density Functional Theory (DFT) and Monte Carlo (MC) methods. Using this approach, we can accurately capture the physical characteristics of these APDs in integrated photonics circuit simulations.
Fig: Schematic diagram of avalanche photodiode model and testbench used in the SPICE simulations.
