With a wavelength in the region of 400-700 nm, visible light has been overtaken by shorter-wavelength, higher-frequency alternatives for electronics manufacturing in recent years.
The shorter wavelength allows finer details to be created using pulses of other forms of radiation.
However, Professor John Fourkas of the University of Maryland chemistry department has found a way of creating integrated circuits using visible-light lasers with very fine detail.
The process is made possible by using a single light pulse to both trigger and deactivate a response from the target medium within an area much smaller than separate activation and deactivation lasers could achieve.
In manufacturing, the desired circuitry is masked on a conducting plate using a photoresistive substance.
The laser then removes the unwanted conductor from around this circuitry, leaving the finely detailed current-carrying threads in place.
Named RAPID lithography, the technique is cheaper than using short-wavelength radiation and can take place without the need for a vacuum.
Posted by Simon Jones
