Ion beam deposition techniques are well known in the field of integrated circuit fabrication. These techniques are of interest because of the capability of ion beam deposition to grow thin film semiconductor layers. The kinetic energy of the ions can enhance the likelihood of epitaxial growth at lower substrate temperatures than are possible with prior art thermal evaporation techniques. Most prior art ion beam deposition techniques utilize sputtering (see T. Ohmi, K. Matsudo, T. Shibata, T. Ichikawa, Appl. Phys. Lett. 53, 364, (1988)). The use of a Si.sup.+ beam for direct deposition onto a Si substrate is another alternative which has been utilized for Si epitaxy at low substrate temperatures, as described in K. J. Orrman-Rossiter, A. H. Al-Bayati, D. G. Armour, S. E. Donnely, and J. A. van den Berg, Nucl. Instrum. Methods B 59/60, 197 (1991), and A. H. Al-Bayati, K. J. Boyd, D. Marton, S. S. Todorov, J. W. Rabakais, Z. H. Zhong and W. K. Chu, J. Appl. Phys. 76, 4383 (1994). Plasma enhanced chemical vapor deposition, although mostly a chemical reaction technique, also utilizes energetic reactive ions, neutral excited molecules and radicals to enhance the growth rate of semiconductor films, as described in T. J. Donahue and R. Reif, J. Appl. Phys. 2757 (1985).
All of the prior art MBE and CVD techniques utilize high growth temperatures and expensive equipment.