Reactive ion etching of a multicomponent glass substrate

A five-component glass has been reactive ion etched with CF4- O2 plasma over a range of pressure, power and gas composition. There are two kinds of components in glass: Those chemically etchable and those chemically non-etchable. For the former both chemical reaction and physical bombardment contribute to the etch. For the latter physical bombardment dominates the etch. A feeding stream concentration change was used to illustrate chemical reaction effects. The cathode self-bias voltage was used to evaluate the bombardment mechanism. The addition of argon into the plasma not only increased the glass etch rate but also smoothed the surface topography. SEM and Auger results proved the existence of differential etching mechanisms for glass components. © 1988, SPIE.