A continuous buried GdSi1.7 layer is formed by channelled implantation
of 90 keV Gd ions into Si(111). In the case of (001) oriented silicon
substrates, the silicide film is formed on the silicon surface. Its w
orse crystalline quality is due to the epitaxy occurring relative to a
ll four(111)si planes resulting in a textured GdSi1.7 layer. Annealing
at a temperature of greater than or equal to 850 degrees C for 30 min
results in the presence of only the orthorhombic GdSi2 phase on the s
ilicon surface for both (111) and (001) silicon substrates. However, t
he precipitates embedded in the silicon substrate are still hexagonal
GdSi1.7. The phase transformation temperature is higher for (111) than
for (001) silicon. (C) 1997 American Institute of Physics.