Plasma lithography could improve chips

A lithography method based on thin plasma beams could make smaller, better performing computer chips.

The new class of nanolithography, under development at the Centre for Materials Under Extreme Environments at Purdue University in Illinois, US, has the potential to extend Moore's law.

The unofficial rule states that the number of transistors on integrated circuits, or chips, doubles about every 18 months.

Computer chips are currently created with ultraviolet light through a process called photolithography. The process involves projecting the image of a mask onto a light-sensitive material, then chemically etching the resulting pattern.

The plasma-based lithography generates ultraviolet light that has a wavelength of 13.5nm, less than one-tenth the size of current lithography.

The researchers shape and control plasma into beams using magnetic fields. This is because plasma, which is a partially ionised, gaslike material, conducts electricity.

The method is adopted from fusion-energy research. In experimental fusion reactors, magnetic fields are used to keep plasma-based nuclear fuel from touching the metal walls of the containment vessel.