DNA ROM, nucleic acid memory and substrate for OxRAM

DNA ROM

National Science Foundation (National Science Foundation, NSF) and Semiconductor Research Corp. (SRC) is investing $ 12 million in the development of a new class of memory and other technologies - in particular, DNA-based persistent storage, nucleic acid memory (NAM), and neural networks based on yeast cells.

The initiative was called semiconductor synthetic biology for information processing and storage technologies (SemiSynBio). SemiSynBio is a joint project of NSF and SRC.

The existing memory is reliable and cheap, but it has certain limitations. The industry is working on the next generation of types of wave memory - magnetoresistive random access memory (MRAM), phase state memory and random access resistive memory (ReRAM). It is non-volatile memory with unlimited durability.

Researchers are also working on an assortment of biological types of memory. Biological structures, combined with semiconductor technology, are capable of storing 1000 times more data than current technologies, and keeping this data for a hundred years or more, while consuming less energy.
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For example, the industry is working on archival storage technologies using deoxyribonucleic acid (DNA). DNA is a promising platform for storing information in electronic devices of the new generation. DNA does not degrade over time and is very compact. It can be used to store a huge amount of data in a very small amount for a very long time.


Researchers use DNA, the basic molecule that encodes genetic information in biology, as a programmable building block — the LEGO molecular block — to create complex materials with special properties

More and more companies are working on storing information in DNA. For example, last year, Twist Bioscience, Microsoft and the University of Washington were able to save audio recordings of two musical performances at the DNA memory jazz festival in Montreux.

In computers, individual units of information are stored in the form of zeros and ones, binary code. DNA molecules encode information through sequences of individual units. In DNA molecules, these units are four different nucleic bases: adenine (A), cytosine (C), guanine (G), and thymine (T).

To encode music into DNA copies for archival storage, Twist Bioscience, Microsoft, and the University of Washington developed a four-step process: DNA encoding, preserving synthesis, extraction, and decoding.

But there are several technical and fundamental obstacles to the implementation of DNA storage.

The SemiSynBio program was invented by the industry in order to overcome these problems. In a project of this initiative, the University of California, Davis, the University of Washington and Emory University are developing a DNA-based ROM. The goal is to create a device that can be programmed at will, read electronically, and combined with conventional semiconductors, ensuring long-term storage and retrieval of data. To this end, researchers have developed several technologies:

• DNA nanowires. They will be grown using the bottom-up self-assembly process, with molecular and ionic additives, and the patterned growth of inorganic structures.
• Rules for the development of multi-level memory cells based on DNA.
• Development of ROM with cross-connection based on DNA.

In addition to DNA ROM, SemiSynBio also finances other projects - nanometer-scale data storage systems using chimeric DNA, storing data in DNA using nanopore-based reading, memory on nucleic acid, bioelectronics based on redox reactions and YeastOns. YeastOns are neural networks that operate on the basis of communications between yeast cells.

As part of the program, the University of Idaho at Boise is developing a nucleic acid memory (NAM). They already have two prototype media - digital NAM (dNAM) and serial NAM (seqNAM).

“In dNAM, information is encoded through a certain spatial orientation of DNA sequences on top of addressable origami DNA nanostructures, which are called NAM storage nodes. DNA origami provides a convenient way and a proven approach to quickly and efficiently prototyping NAM nodal structures, according to the NSF. "In seqNAM, information is encoded in chunks of data contained in individual molecular chains."

Dawn Tilbury, assistant engineering director at NSF, said: “The opportunities we have today have seriously advanced compared to what was several decades ago, but materials such as silicon have physical limitations that constrain calculations on very small scales. Materials and schemes of work on the basis of biology hint at very interesting opportunities that can overcome these obstacles, and with lower energy costs. "

Erwin Gianchandani, interim deputy director of NSF for computer science and information and engineering, added: “This research will pave the way for devices with much greater data storage capabilities and much less demand for energy. Imagine, for example, that we can record all the contents of the Library of Congress on a device the size of your fingernail. ”

OxRAM substrates

The CEA Tech Laboratories Electronics and Information Technology (LETI) and CMP service center, engaged in prototyping and manufacturing of small batches of integrated circuits and microelectromechanical circuits , presented the first industrial process for producing multi-purpose substrates (multi-project-wafer, MPW) for manufacturing OxRAM devices at 200mm platform.

OxRAM is a new non-volatile memory, a subspecies of resistive memory (ReRAM). In general, there are two main types of ReRAM - oxygen-deficient ReRAM and CBRAM. The oxygen-deficient ReRAM is known as oxide-based ReRAM, or OxRAM. OxRAM can be used as internal memory on microcontrollers or security products, as well as to speed up AI and neuromorphic computing.


OxRAM structure

Production of multi-purpose substrates goes on 200mm CMOS-line LETI. The service allows the development of OxRAM. It includes a set of masks called the “Memory Advanced Demonstrator (MAD)” using the OxRAM technology. The new technology platform will be based on active layers of hafnium oxides with the addition of titanium. This technology comes with practical design examples, including mock-ups, quality control and simulations. Libraries with a large number of active and passive electro-optical components are provided.

Etienne Novak, head of the LETI Advanced Memory Laboratory, said: “This opportunity, together with our advanced memory demonstrator platform, is based on a large set of tools that allows you to conduct various research with our partners, and provides an opportunity to verify the effectiveness of various non-volatile memory solutions.” .

Jean-Christophe Krebe, director of CMP, added: “This is an opportunity for many universities, start-ups and small enterprises in France, Europe, North America and Asia to take advantage of the new technology and service.”

Biological microscopy

IMEC received a grant of € 1.5 million for the development of ultra-compact microscopy based on photonics on a chip and CMOS image sensors. IMEC will develop a technology called integrated microscopy on a chip with high resolution structured illumination (IROCSIM). This technology can be used in the study of DNA, biology and medicine.

Niels Warellen, chief photonic researcher and project manager at IMEC, said: “High-resolution compact and high-performance microscopy will cause serious changes in the field of biological research, in facilitating access to DNA sequencing technology, in the diagnosis of certain diseases, in the study of new drugs in pharmacology, and diagnosing patients in remote locations. ”