Moving along the lines of developing more capable storage devices, researchers at the University of Alberta Canada have devised a way to replace hydrogen electrons on a silicon wafer using a scanning tunneling microscope (STM).
This could lead to a storage density of around 138 TB per square inch, roughly 1,000 times more than the storage devices currently available.
STM was first developed more than 30 years ago at IBM which managed to store data in a single atom last year. The approach acquired by the Canadian researchers uses STM to knock off an individual hydrogen atom from the surface of a silicon wafer using a voltage pulse.
The vacancies created as the atom is removed can be “patterned on the surface to create devices and memories.” And this removal and replacement of atoms create the logical 0s and 1s that are used to store data.
In order to achieve a design, the entire replacement process has been automated, according to Roshan Achal who is leading the project.
He acknowledges that their approach is highly accurate, but it’s not error-proof. For instance, an atom may get knocked off from an unwanted location. A workaround is already in place which eliminates the need for starting all over again from scratch.
The project also addresses various hurdles including extremely low temperatures that are required for such procedures to work. With their approach, it’s possible to fabricate designs that are stable at room temperature.
“This stability comes at the cost of increased difficulty in fabricating structures. However, with these new techniques we have overcome many of the associated problems, making this system a very interesting candidate for new technological applications,” said Achal.
There is another major aspect on which the researchers are working: speed. A convenient way to improve speeds to increase the number of tips that are used to replace atoms.
The research has been published in the Nature Communications journal.