On the dynamics of laser-induced etching of tungsten–SiO -composites

Cw laser-induced heating of W–SiO2-layer composites in a WF6-atmosphere results in a locally well defined removal of W from the SiO2 substrate. High-resolution etching is possible due to the nonlinearity of the reaction kinetics. The etching process has been simulated using a three-dimensional numerical model, which takes into account the time-dependent evolution of the etch front and the corresponding temperature distribution. All temperature dependent material parameters and time-dependent absorption characteristics have been included in the calculations. The results obtained from the model have been compared with experimental investigations. q1999 Elsevier Science B.V. All rights reserved