AFM studies of swift heavy ion-irradiated surface modification in Si and GaAs

Abstract

Atomic force microscopy (AFM) studies of Swift Heavy Ions (SHI ∼100 MeV Si 7+ and Au 7+) irradiated Si and GaAs surfaces have been performed for a variable fluence in the range of 10 10– 10 13 ions cm −2 . The craters with piled up material, which is called hill, are clearly seen in the micrographs. A significant direct observation of amorphization (or melting due to SHI irradiation damage), plastic flow and subsequent recrystallization in the form of platelets has been made. The quantitative estimation of the features revealed that the volume of the craters for silicon ion irradiation is smaller than the gold ion irradiation. However, surface roughness has been found to be enhanced after the irradiation. Moreover, the GaAs surfaces were found to be less rough than the Si surface. The features are related to the difference in electronic energy loss of incident ions, thermal diffusivity, thermal conductivity and density of the target materials.