Chinese team says new storage chip material has a near-infinite lifespan
Ferroelectric material has potential to reduce data centre costs and could have applications in deep-sea exploration or aerospace.
This new type of ferroelectric material could potentially reduce data centre costs and have applications in deep-sea exploration or aerospace in the future.
The move prompted China to invest heavily in technology to replace this equipment and develop new parts, and it has since achieved mass production of storage chips, breaking the monopoly held by foreign manufacturers in the industry.
As a result, the price of storage chips has fallen dramatically in the past year, in some cases by up to 90 per cent. These storage chips are used for computer memory, automotive chip memory, solid-state drives, USB drives and smartphone flash memory.
Ferroelectric materials are among the most ideal for making storage chips due to their low power consumption, lossless reading and fast writing capabilities.
Ferroelectricity allows these materials to rapidly switch states under an electric field – a process known as polarisation – which remains stable even after the field is removed. It can be likened to a form of permanent rapid memory.
These materials are already used in storage technology, sensors and energy-harvesting devices, and they could be used to build storage servers or to support large data centres in the future – potentially having an impact on the US-China rivalry over AI technologies.
But traditional ferroelectric materials that are widely used commercially – like lead zirconate titanate, or PZT – can experience what is known as ferroelectric fatigue during use, leading to performance degradation and eventual failure.
The Chinese team set out to tackle this problem by improving the structure of the material.
The research was led by Professor Zhong Zhicheng from the Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences (CAS), in collaboration with Professor Liu Fucai from the University of Electronic Science and Technology of China in Chengdu, Sichuan, and Professor Li Wenwu from Fudan University in Shanghai.
Their findings appeared in the peer-reviewed journal Science on June 7.
In a separate report on the CAS website, the researchers noted that ferroelectric fatigue was caused by defects in the materials.
“When charges flow during storage and read processes, those defects move and accumulate, eventually blocking the polarisation process and leading to device failure,” He Ri, an associate professor with the CAS institute and first author of the study, was quoted as saying.
“It’s like waves gathering small stones in the sea, gradually forming a large reef that blocks the flow of the waves.”
The team found the problem could be solved when ferroelectric materials were constructed in layers.
Using AI-assisted atomic-level simulations, they discovered that two-dimensional sliding ferroelectric materials shift as a whole during charge transfer when placed under an electric field. That prevents the movement and accumulation of charged defects, so fatigue is avoided.
The team came up with a nanometre-thick two-dimensional layered material that they called 3R-MoS2. A nanometre is about 100,000 times smaller than the diameter of a human hair.
“Laboratory tests showed that 3R-MoS2 exhibited zero performance degradation after millions of cycles, suggesting that storage devices made from this new two-dimensional sliding ferroelectric material have no read/write limitations,” the CAS report said.
“This means that while traditional ion-type ferroelectric materials, such as PZT, allow for tens of thousands of read/write cycles, storage devices made from the new two-dimensional layered sliding ferroelectric material have no such limitation,” He was quoted as saying.
With no read/write limits, storage chips made from this material would be extremely durable, and that, according to the scientists, would make them ideal for use in extreme environments such as aerospace and deep-sea exploration.
And given how tiny the material is, it would significantly increase the storage density in large-scale applications such as data centres.
In a previous study, the CAS institute developed a new material combining elasticity and ferroelectricity, which they found was resistant to both mechanical and ferroelectric fatigue. The aim was to use it in wearable electronic devices, but it was not as durable as the latest material.
Meanwhile, a new study from researchers at the Massachusetts Institute of Technology and Cornell University looked at the potential of multilayered materials for storage chips, based on boron nitride. Their findings were also published in Science on June 7.