  200 nm thick SiO2 layers grown on Si substrates and Ge ions of 150 keV energy
were implanted into SiO2 matrix with Different fluences. The implanted samples
were annealed at 950 C for 30 minutes in Ar ambience. Topographical studies of
implanted as well as annealed samples were captured by the atomic force
microscopy (AFM). Two dimension (2D) multifractal detrended fluctuation
analysis (MFDFA) based on the partition function approach has been used to
study the surfaces of ion implanted and annealed samples. The partition
function is used to calculate generalized Hurst exponent with the segment size.
Moreover, it is seen that the generalized Hurst exponents vary nonlinearly with
the moment, thereby exhibiting the multifractal nature. The multifractality of
surface is pronounced after annealing for the surface implanted with fluence
7.5X1016 ions/cm^2.
