Rapid laser-induced chemical etching of semiconductors

Abstract

Laser-induced chemical etching has been demonstrated in a variety of materials including metals, ceramics, insulators and semiconductors. Depending on the laser and the gas used, etching can be quite rapid, especially when compared with reactive ion etching rates. Since it is frequently desirable to work with a gas-solid system that is inert in the absence of radiation, rather high power densities are often required to achieve etching. When the solid is the principal light absorber in the system, such power densities result in intense local excitation of the solid, as well as heat. Using semiconductor etching as an example, several factors which may be responsible for fast etch rates have been identified. These include the consequences of high temperatures at the solid surface, as well as evidence for participation of photo-generated carriers in the etching chemistry in a model system. © 1983 SPIE.