THERMODYNAMIC MODELING OF SELECTIVE CHEMICAL VAPOR-DEPOSITION PROCESSES IN MICROELECTRONIC SILICON

As the dimensions of electronic circuits continue to decrease, reaching the submicron size, the importance of selective deposition processes is becoming obvious. For silicon-based IC technology, three selective chemical vapor deposition processes have been reported so far: epitaxial silicon, polycrystalline metals, mainly tungsten and refractory metal silicides, TiSi2 and TaSi2. A thermodynamic approach of the selective deposition of epitaxial silicon has already been performed and we will just recall the main results. By comparison, there are only few reported thermodynamic analyses of the selective deposition of metals and. metallic alloys. We will show that even if surface reactions and kinetics play an important role in these processes, thermodynamic equilibrium calculations performed in the corresponding system by the free energy minimization technique may lead to a better understanding of the selective deposition of these materials. © 1990, American Vacuum Society. All rights reserved.