A critical comparison of reactive etching of materials in microelectronics, fusion and space technologies.

Chemical and radiation-enhanced gas-solid etching of materials that are important in microelectronics, fusion and space technologies, are compared and reviewed. The basic processes that drive spontaneous etching of several etchant-material combinations are similar: F/Si, H/Si and H/C can be cited as examples. On the other hand, many etchant-material systems appear to involve system-specific processes that should not be generalized: examples are the XeF(2)/Si and Cl/Si systems. Experiments show that chemical etching is generally enhanced when the flux of thermalized active species to surfaces is accompanied by energetic particle or photon bombardment. In microelectronic materials etching, investigators have systematically studied etching product yield and product kinetic energy as a function of ion mass, ion energy and angle of incidence; data on temperature dependence of etching are more limited.