A. Markwitz et al., MICROSTRUCTURAL INVESTIGATION OF ION-BEAM SYNTHESIZED GERMANIUM NANOCLUSTERS EMBEDDED IN SIO2 LAYERS, Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms, 142(3), 1998, pp. 338-348
Ion beam synthesised Ge nanoclusters in amorphous SiO2 layers were pro
duced by ion implantation and subsequent annealing and investigated by
cross section transmission electron microscopy (TEM). After annealing
in inert atmosphere at appropriate temperatures, a Ge cluster band wi
th sharp transitions regions appear around the projected range of the
implantation profile. The size of the Ge nanoclusters in the band vari
es from a few nanometers at the transition regions up to about 10 nm i
n the middle of the band and depends strongly on the annealing tempera
ture and time. The Ge clusters are crystalline with a lattice constant
slightly higher than that of Ge bulk material. Much larger Ge cluster
s line up far from the maximum of the implantation profile (position o
f the mean projected range) have diameters up to 40 nm if the annealin
g conditions were changed to an H-2 containing atmosphere. The results
of cross section TEM are supported by scanning TEM analysis combined
with an energy dispersive X-ray detection system and RES investigation
s. (C) 1998 Elsevier Science B.V. All rights reserved.