Surface Etching by Laser‐Generated Free Radicals

We have found that reactive neutral fragments, generated by multiple infrared photon dissociation of various molecules with a laser, are capable of etching silicon oxide or nitride surfaces. The laser‐generated radical etching process has a potential for major commercial impact, by eliminating ion‐bombardment damage in the resulting semiconductor device and by permitting more efficient and selective etching to be performed. In addition, this provides an investigative tool for learning the precise identity of the active species, the extent of their interaction with the substrate surface, and the rates of the key steps in the reactions resulting in net removal of silicon.