Recently, the research team at CEA-Leti successfully demonstrated a ferroelectric capacitor platform (FeRAM) based on hafnium zirconium oxide (HfZrO) at the 22nm FD-SOI technology node. This breakthrough technology advancement not only drives the development of ferroelectric memory (FeRAM) technology, but also provides more efficient, energy-efficient, and cost-competitive memory solutions for embedded applications such as the Internet of Things (IoT), mobile devices, and edge computing. In this article, we will provide an in-depth analysis of the core highlights, technical challenges, and future prospects of this technological breakthrough.
A breakthrough in ferroelectric capacitor platforms
The hafnium zirconium oxide (HfZrO)-based ferroelectric capacitor platform showcased by CEA-Leti is the first time that this new ferroelectric material has been integrated into the back-end (BEOL) of the 22nm FD-SOI technology node. HfZrO is a CMOS-compatible ferroelectric material whose ferroelectricity is derived from the electrode properties in HfO2-based films, which has better scalability compared to traditional perovskite materials such as PZT. By combining the HfZrO material with the 22nm FD-SOI node, the researchers not only break through the limitations of existing FeRAM technologies, but also greatly improve the scalability and performance of embedded applications.
The demonstration of this platform represents a significant advance in ferroelectric memory technology, providing a more stable, efficient, and low-power memory solution for more embedded systems in the future. Traditional FeRAM products mostly use perovskite materials such as PZT, but their biggest problem is that they are not compatible with CMOS processes and cannot be scaled to technology nodes below 130nm. In contrast, HfZrO materials have better CMOS compatibility and can be effectively scaled to smaller nodes, adapting to the dual performance and power consumption requirements of modern embedded systems.
Solving the limitations of traditional technology: the breakthrough and application of new materials
Currently, embedded FeRAM products rely heavily on perovskite materials such as PZT, which perform well in process nodes at 130nm and above, but face compatibility and performance bottlenecks at nodes below 130nm. As a new type of ferroelectric material, HfZrO's ferroelectric properties are derived from the crystal structure in HfO2-based films, and it has been successfully compatible with CMOS processes. This discovery significantly broadens the field of application of FeRAM, especially in the context of the increasing demand for low-power and high-density embedded memory.
It is worth noting that although previous studies have demonstrated the application of HfO2-based ferroelectric thin films at the 130nm node, this achievement by CEA-Leti has successfully pushed the HfZrO FeRAM technology to the 22nm FD-SOI node. By implementing this technology at a smaller node, CEA-Leti not only demonstrates the scalability of the technology, but also effectively solves the technical challenges posed by the size reduction, especially the need to fabricate functional 2D and 3D ferroelectric capacitors while maintaining a low HfZrO thin film crystallization heat budget.
Figure: CEA-Leti brings breakthroughs to future embedded applications
Application scenarios and prospects
The HfZrO-based FeRAM platform offers significant advantages in several embedded application scenarios, especially in the following areas:
IoT, IoT devices often require memory modules with high performance, low power consumption, and long lifespan. The HfZrO FeRAM platform not only provides faster response times, but also significantly reduces power consumption, making it promising for a wide range of applications in IoT devices.
Mobile devices, such as smartphones and tablets, increasingly require memory modules to minimize power consumption and extend battery life while maintaining high performance. The low-power nature of the HfZrO FeRAM platform is a perfect fit for this need.
Edge Computing, in edge computing, the performance of embedded memory is critical due to the fast response time and often stringent power requirements for data processing. FeRAM technology based on HfZrO can provide low-power and high-speed storage solutions, especially for embedded systems in edge computing.
Technical challenges and innovative solutions
While there is great potential to push FeRAM technology to the 22nm node, there are also significant technical challenges. For example, it is a complex project to successfully fabricate functional 2D and 3D ferroelectric capacitors at such a small node, while maintaining a low temperature budget and low crystallization temperature. In response to these challenges, the CEA-Leti research team successfully implemented the integration of HfZrO FeRAM on the 22nm FD-SOI node through precise process control and innovative material selection, opening up a new path for ferroelectric memory technology.
Future Plans and Prospects
CEA-Leti's research team is already accelerating the development of HfZrO FeRAM, planning to demonstrate smaller embedded Mbit memory arrays that will operate at about 1V and have high access rates for ultra-low-power applications. In addition, CEA-Leti plans to transfer this technology to foundries to promote its application in the commercial field.
Summary
CEA-Leti's successful demonstration of a HfZrO-based ferroelectric capacitor platform at the 22nm FD-SOI node brings a breakthrough to embedded FeRAM technology. This technology not only solves the compatibility and scalability issues of traditional FeRAM materials, but also provides faster, more energy-efficient, and more cost-effective memory solutions for areas such as IoT, mobile devices, and edge computing. As R&D continues to advance, HfZrO FeRAM will play an important role in the field of memory technology in the future, driving the development of next-generation embedded applications.
