Effects of Al Films on Ion-Implanted Si

Ion-implanted amorphous regions of Si in the presence of Al films 300–700 Å thick are found to recrystallize between 325 and 350°C. This recrystallization occurs at a temperature significantly below both the epitaxial regrowth of the amorphous Si (∼ 600°C) and the Al–Si eutectic of 577°C. In the case of the 300-Å metallizations, the enhanced low-temperature reordering of the damaged layer is simultaneously accompanied by an interfacial migration which results in Si transport to the surface of the sample. The observed phenomena are analyzed as a function of anneal temperature by 280-keV α-particle backscattering and 1.8–6.2-eV optical reflectance measurements.