Using previously patented technology, the H-P scientists have created a 64-bit memory unit that fits inside a square micron (a micron is one millionth of a meter). Some thousands of these memory units could fit on the end of a single strand of hair.
Its capacity is too low to be useful yet but it is a key advance in what is called nanotechnology — manipulating molecules and atoms.
In about 10 years’ time the possibilities of further miniaturization with current chip-making technology will end. Currently, tiny circuits and transistors are etched onto metal films on top of silicon by using optical equipment.
Chips need to become smaller in order to become cheaper, faster and more energy-efficient.
“Capacity and performance could be extended enormously by layering molecular-switch devices,” said R. Stanley Williams, H-P Fellow and director of Quantum Science Research at H-P Labs.
The H-P work, which is still at a very early stage and which could take many more years to become commercial, also combined for the first time both memory and logic by manipulating molecules caught in a grid of superthin platinum wires.
A piece of logic is needed to make memories practical.
The 64-bit memory contains 64 bits of information. In this case, each bit was formed by one or a few molecules sandwiched between two sets of superthin platinum wires, one set running north-south, one set east-west.
At the junctions of the grid the molecules could be switched “on” or “off” by sending an electronic current through the platinum wires. Combinations of these “on” and “offs,” or “zeros” and “ones,” can store characters or instructions.
By sending a lower voltage current through the wires, the zeros and ones could be read.
“This is the first demonstration that molecular logic and memory can work together on the same nanoscale circuits,” said Williams in an announcement. He is expected to discuss the experiments at a conference in Stockholm later on Monday.
The researchers also proved they can use a previously invented technology to “stamp” the 64 bit memory from a mold or master. The memory was created on top of ordinary silicon used in today’s chip making production processes.
Today’s lithography chip production process takes many weeks, often months, to etch layer after layer of circuitry on top of silicon wafers. The “stamping” or “printing” method used by H-P scientists could dramatically reduce production time.
It took the researchers just a few minutes to “stamp” the memory. The memory they created is non-volatile, which means the molecules stay in their position, and retain their information, when the current is switched off.
Today only the more expensive memory chips, like flash memory, remember their information after power has been turned off.
The little piece of 64-bit memory H-P molded from “smart” molecules does not yield a useable chip yet. Today’s standard DRAM memory chips used in most personal computers contains 256,000,000 bits of memory.