Adsorption and desorption of C-60 molecules on GaN{0001}-1x1 surfaces as we
ll as the surface decomposition by heating were investigated with Auger ele
ctron spectroscopy. The first monolayer of C-60 forms strong chemical bonds
to the substrate atoms. A seven-step annealing procedure at temperatures u
p to 1275 K is presented which completely removes the adsorbed carbon witho
ut decomposing the surface. If the process is applied to clean, uncovered G
aN{0001}-1x1 surfaces thermal etching with a significant Ga atom loss is ob
served. The results indicate that adsorbed C-60 increases the thermal stabi
lity of the surfaces considerably and that thermal etching begins at defect
s or steps at the surface where the molecules are most strongly bound. (C)
2000 American Institute of Physics. [S0003-6951(00)04829-4].