PLASTIC MEMORY
A conducting plastic has been used to create a new memory technology with the potential to store a megabit of data in a millimeter-square device - 10 times denser than current magnetic memories. The device should also be cheap and fast, but cannot be rewritten, so would only be suitable for permanent storage.
The device sandwiches a blob of a conducting polymer called PEDOT and a silicon diode between two perpendicular wires. Substantial research effort has focused on polymer-based transistors, which could form cheap, flexible circuits, but polymer-based memory has received relatively little attention.
The key to the new technology was the discovery by researchers from Princeton University, New Jersey, and Hewlett-Packard Laboratories in Palo Alto, California, that passing a high current through PEDOT turns it into an insulator, rather like blowing a fuse. The polymers two possible states, conductor or insulator, then form the one and zero necessary to store digital data.
"The beauty of the device is that it combines the best of silicon technology - diodes - with the capability to form a fuse, which does not exist in silicon," says Vladimir Bulovic, who works on organic electronics at the Massachusetts Institute of Technology.
However, turning the polymer INTO an insulator involves a permanent chemical change, meaning the memory can only be written to once. Its creators say this makes it ideal for archiving images and other data directly from a digital camera, cell phone or PDA, like an electronic version of film negatives.
Ion snatch:
PEDOT's ability to conduct electricity means it is already used widely as the anti-static coating on camera film. But until now, no one suspected that it could be converted into an insulator.
The material is a blend of a negatively-charged polymer called PSS- and a positively-charged one called PEDT+. Having distinct, charged components allows it to conduct electricity and means that it is water soluble.
The team is not sure why it stops conducting when high currents pass through. But Princeton researcher Stephen Forrest suspects that the heat produced by a high current gives the PSS- layer sufficient energy to snatch a positively-charged hydrogen ion from any water that has dissolved on its surface, forming a neutral PSSH.
Without the negatively-charged PSS- to stabilize it, PED+ in turn grabs on to an extra electron and also becomes neutral, converting PEDOT into an insulating polymer.
Read and write:
To store the memory, the researchers use the wires and the diode surrounding the PEDOT blob to run either a high or a low current through it. This either creates an insulator or leaves it as a conductor.
To read the memory, they run current through the top wire and measure the current in the bottom wire. No current means the bit is a zero, and vice versa.
In their paper in Nature, the researchers describe just one such junction. But for a memory application, the device will need many more. So the Hewlett-Packard team is now working on building a grid of intersecting wires. In this way, they can read and write multiple bits to one device. A grid system is commonly used in display screens to switch individual pixels.
Polymer devices can spray or printed, and are therefore much cheaper than silicon devices, which must be etched.
Cheap, Plastic Memory for Flexible Devices
Cheap and plastic aren't words often associated with cutting-edge technology. But researchers in Tokyo have created a new kind of plastic low-cost flash memory that could find its way into novel flexible electronics.
Flash memory stores data electrically, in specially designed silicon transistors. Information can be recorded and read quickly and is retained even when the power is off. This makes flash ideal for MP3 players, cameras, memory cards, and USB drives. But the technology is still more expensive than conventional hard disks.
The prototype plastic flash memory cannot match silicon's storage density, long-term stability, or number of rewrite cycles. But its low cost could make it possible to integrate flash memory into more unconventional electronics. For example, cheap plastic memory devices might be incorporated into e-paper or disposable sensor tags.
APPLICATIONS:
Memory Expanding Flechettes
Memory Expanding Flechettes (more commonly known as Expanders) borrow bleeding-edge technology from the famous Spawn Blades and adapts it to firearms use. Each flechette in the cluster expands and compresses (thanks to memory plastics) to roughly the shape and size of a quarter once inside a soft target. They penetrate armor as well as most flechettes (1/2 SP), but do terrifying damage once beyond it (increase penetrating damage by 50%). Due to the multiple hits, armor penetrated is reduced 3 levels.
BallisTech Skintight Mark III:
Skintight body armor was first introduced for police use in 2013. At the time it was a remarkable piece of Memory Plastic technology that made claims it couldn't hold up to. The 2021 edition (mark III) is finally a body armor people are looking at again. Not incredibly useful on its own, it is at it's best under another layer of armor. Treat Skintight as being SP40, but any damage up to that 40 mark is no prevented, it is only reduced by 1/3 as the thin layer of memory plastic attempts to redirect the kinetic energy across the material instead of through it. Damage over the 40 mark is dealt in full (with AP rounds of course reducing this to 20). Any time the armor is penetrated, reduce this threshold by 5SP. directly after the impact, the suit is stiff and hard from the memory plastics redirecting the impact energy, and the suit gains an EV of 1. If the suit collects more than 3 hits in one round it becomes EV 2 as it stiffens even further. The EV is reduced by 1 point at the beginning of every round as the suit softens again. The suit covers the full body except the head, hands and feet.
