Researches at Osaka University have been doing some really tiny writing lately, using their newly-invented atomic pen, which can draw atom by atom. The resulting letters, the words "Si" for silicon or "Yes" in Spanish, measure only 2 x 2 nanometers, roughly 40,000 times smaller than the width of a human hair. According to Masayuki Abe, one of the project scientists, they have reached a limit impossible to surpass:
It's not possible to write any smaller than this.
They achieved the atomic pen using the tip of an atomic force microscope, which interacts with the surface of a semiconductor when it's near it by exchanging silicon atoms. According to the scientists, this is a new step towards the miniaturisation of chips, which will eventually take us to impossibly-small computers. [Pink Tentacle]