The identification of key variables in the solid phase epitaxial growth of silicon

Silicon solid-phase epitaxy utilizing Al as the transport medium was carried out using either 〈111〉 or 〈100〉 Si single-crystal substrates. By analyzing samples made by a different method we show that the presence of a barrier on the metal plays a fundamental role. The barrier inhibits the diffusion of the metal through the evaporated semiconductor. In the case of Al, the barrier is made by deposition of a thin oxide layer grown on top of the metal, by leaving the sample in vacuum for two days, or by heating the sample in vacuum before the Si deposition.