Ferroelectric devices based on doped hafnium oxides (HfO₂) have been reported as great candidates for low-power logic, nonvolatile memory (NVM), and in-memory computing applications due to their compatibility with CMOS technology. They have several advantages over other types of electronic devices, including high endurance, low power consumption, and fast switching speeds.
NCFET has been reported to overcome the fundamental limit of conventional CMOS technology (60 mV/dec). It can be used in low-power circuit applications due to the internal voltage amplification provided by the ferroelectric layer. Additionally, it can offer a higher ON current and a lower threshold voltage compared to conventional FETs.
We have studied the device physics and modeling of these devices to design next-generation electronic circuits.
ULTRARAM is a non-classical charge-trapping-based emerging NVM that exhibits fast, non-volatile, high endurance (>10^7 P/E cycles), long retention (>1000 years), and ultra-low switching energy per unit area characteristics. It breaks the paradigm of the unachievable universal memory idea. Unlike a single SiO2 barrier in a flash, the novelty lies in the InAs/AlSb triple-barrier resonant tunneling (TBRT) mechanism. The TBRT structure provides a high-energy electron barrier with no bias, allowing fast resonant tunneling at program/erase pulses (±2.5V) with a switching energy approximately ten times smaller than that of Flash. However, ULTRARAM is in its early stages of development and needs to overcome several challenges.
We have developed a physics-based model that captures charge trapping and detrapping in the floating-gate (FG) using TBRT physics, which is used to calculate device characteristics. This model can be used for circuit design with a ULTRARAM memory device.
Machine learning (ML) is revolutionizing Electronic Design Automation (EDA) by improving efficiency, accuracy, and scalability in the design and optimization of electronic systems. Both foundries and design companies rely on EDA to support their businesses. A key component in EDA that bridges the foundry technology and IC design is device compact models. ML models, such as neural networks and reinforcement learning, reduce simulation overhead, automate repetitive tasks, and provide predictive insights into design metrics. Additionally, ML-assisted algorithms can be used to optimize advanced node semiconductor devices. There are many ways to optimize two or more target objectives. On the one hand, we have TCAD-based optimization, a trial-and-error method that requires experience and a deep understanding of device physics. In contrast, the other method is a framework that utilizes an ML-assisted genetic algorithm to maximize or minimize the value of target objectives.