KIST develops bendable orgarnic carbon nano compound 64bit memory

Feb 18, 2014
Organic Carbon Nano Compound-based 64-bit Memory Cell Array. (a) Illustration of as-fabricated 1D-1R organic carbon nano compound-based 64bit memory cell array on a flexible PEN substrate (b) Optical image (c) Schematic of unit cell: 1D-1R organic memory (d) Chemical structure of diode layer used for cell (e) Chemical structure of memory layer used for cell. Credit: Nature Communications, DOI: 10.1038/ncomms3707

With the introduction of curved smartphones, flexible electronic goods are gradually moving to the center stages of various markets. Flexible display technology is the culmination of the latest, cutting-edge electric cell device technology. Developing such products, however, requires not only a curved display, but also operational precision of other parts, including the memory, in a flexible state.

Dr. Tae-Wook Kim at KIST announced their successful development of a 64-bit memory array using flexible and twistable carbon nano material and organo-polymer compound, which can accurately store and delete data.

The most common memory cell today uses a silicone (Si)-based hard, inorganic matter, however, in order to be flexible, the materials were fabricated with a carbon-based organic compound. The recently developed memory cell uses a technology, which arranges such organic material in a single configuration at room temperature and places the material on a desired spot on the substrate. This is the core technology in enlarging the storage capacity of memory, an unprecedented discovery until now. In particular, demonstrating this on a bendable substrate required highly sophisticated technology, which signified difficulties in fabrication. The research team developed a technology with the above characteristics to make the electric current flow in one direction so that the data could be rewritable even in a curved state.

Fig. 2 (a) is the picture of a previous organic resistive flexible memory cell. Due to the interference of nearby cells (b), the current value ‘0’ is mis-read as ‘1’ as illustrated in the left bar graph in (c). The recently developed all-organic 1D-1R diode (d) does not suffer from cross-talk between cells (e), and as shown in the bar distribution, it accurately reads the current values ‘0’ and ‘1’. Fig. 2 (f) shows the demonstration of the acronym for the Korea Institute of Science and Technology, ‘KIST’ based on the distribution of the current values ‘0’ and ‘1’ and by using the ASCII code. Credit: Nature Communications, DOI: 10.1038/ncomms3707

In the past, each memory device was configurated with a grating structure, but there were complications in commercializing such device due to inaccuracy in storage and deleting data caused by a cross-talk between cells in the process of expanding its capacity. Therefore, research had continuously been conducted not only on bending the memory, but on resolving such intervention issues and enhancing accuracy.

In this research, organic (resistors) based on carbon nano compounds and organic diodes to control the direction of electric currents were stacked upon each other. Once the direction of the electric current is controlled and can be made to flow in one direction, data can be made rewritable, thereby limiting any interference from nearby cells. These cells are constructed in the form of 1D-1R (1 Diode + 1 Resistor)*, which gives them flexibility with accuracy in data processing.

Previous cells were fabricated with the spin-coating method, a major solution process. However, in a continuous process such as above, the organic diode layer (1D) and the organic memory layer (1R) were damaged. Dr. Kim utilized the crosslinker** method, which can create patterns in a low temperature process, to resolve this problem. The crosslinker method enables the organic memory layer and organic diode layer to avoid damaging each other in the process of creating continuous layers. By using this method, his team managed to develop a non-volatile (where the storage capacity remains undisturbed even with the suspension of power) memory cell with an organic architecture, which was applicable on a twistable plastic substrate and with a 64-bit .

In order to confirm whether the problem of cross-talk between cells was resolved, the research team succeeded in storing the letters 'KIST' while the device was bended. Such results prove that organic memory cells can also be utilized in parts of other flexible electronic goods, in addition to previous electronic cells.

According to Dr. Kim, "This research unveils the direction for research to resolve the greatest obstacle in organic memory cell research with past structures, and is expected to contribute broadly to future research on flexible electric cells and parts."

Explore further: New research could lead to less expensive solar panels

More information: Paper: "Flexible and Twistable Non-volatile Memory Cell Array with All-organic One Diode-one Resistor Architecture," Nature Communications, DOI: 10.1038/ncomms3707

* 1D-1R (1 Diode + 1 Resistor) array: An architecture where a resistor, which is a memory cell, is piled upon a diode, and controls the direction of electric currents.
** Crosslinker Method: A method of subjecting organic matter to ultraviolet rays to solidify the desired part with light. It can be demonstrated in a low temperature process, but it is also a way to chemically stabilize the organic matter while enabling it to maintain its original characteristics after fabrication.

add to favorites email to friend print save as pdf

Related Stories

One step closer to low cost solar cells

Jan 27, 2014

The dwindling resources for conventional energy sources make renewable energy an exciting and increasingly important avenue of research. However, even seemingly new and green forms of energy production, like ...

How organic magnets grow in a thin film

Mar 23, 2013

(Phys.org) —Development of organic single molecule magnets opens a great many of applications for magnetic materials and new memory technologies. Organic magnets are lighter, more flexible and less energy intensive in production ...

Organic flash memory developed

Dec 17, 2009

(PhysOrg.com) -- Researchers at the University of Tokyo have developed a non-volatile memory that has the same basic structure as a flash memory but is made from cheap, flexible, organic materials.

Silicon oxide memories transcend a hurdle

Jul 09, 2013

A Rice University laboratory pioneering memory devices that use cheap, plentiful silicon oxide to store data has pushed them a step further with chips that show the technology's practicality.

Recommended for you

Form Devices team designs Point as a house sitter

12 hours ago

A Scandinavian team "with an international outlook" and good eye for electronics, software and design aims to reach success with what they characterize as "a softer take" on home security. Their device is ...

Man pleads guilty in New York cybercrime case

15 hours ago

A California man has pleaded guilty in New York City for his role marketing malware that federal authorities say infected more than a half-million computers worldwide.

Dish restores Turner channels to lineup

Nov 21, 2014

Turner Broadcasting channels such as Cartoon Network and CNN are back on the Dish network after being dropped from the satellite TV provider's lineup during contract talks.

LiquidPiston unveils quiet X Mini engine prototype

Nov 21, 2014

LiquidPiston has a new X Mini engine which is a small 70 cubic centimeter gasoline powered "prototype. This is a quiet, four-stroke engine with near-zero vibration. The company said it can bring improvements ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.