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A nanorelief forming on a copper surface under oblique irradiation with cluster ions has been examined at different irradiation doses and target temperatures. This nanorelief has been found to evolve into an ordered undulating structure. It has been demonstrated that the initial roughness is smoothed out at higher target temperatures. The mechanisms of formation of the surface topography have been identified, and their efficiency has been determined.

We have studied a new approach to the analysis of carbon-containing materials by secondary ion mass spectrometry (SIMS), which allows determining the contents of carbon atoms in sp2 and sp3 hybridization states. According to this, the main SIMS parameter characterizing the atomic concentration N(sp3) is defined as the intensity ratio of C8/C7 secondary cluster ion peaks. Based on the results of SIMS analysis of several test compositions, a calibration dependence of N(sp3) versus C8/C7 peak intensity ratio has been obtained. The depth profiles of N(sp3) for diamond-like carbon (DLC) grown on diamond and silicon substrates were obtained, which showed (i) N(sp3) variation from 0.3 to 0.6 depending on the DLC growth regime and (ii) inhomogeneous distribution of N(sp3) in depth of the samples.

Results of investigation of the mass spectra of secondary ions sputtered from bulk (continuous) and porous silicon targets with various characteristic core particle dimensions are presented. It has been established that the sputtering of nanostructured Si samples leads to a significant increase in the relative yield of massive cluster ions. This effect is especially pronounced when the characteristic nanoparticle size approaches the range of bombarding ions in the Si target. The obtained results are explained taking into account the confinement of atomic collision cascades.

We have studied the influence of bombardment with accelerated gas-cluster ions on the surface topography of silicon carbide and diamond. Atomic-force microscopy shows that exposure to 10-keV gas-cluster ions at a total dose above 1016 cm–2 leads to smoothing of the surface relief. The ion-etching rate and efficiency of the surface relief smoothing as dependent on the thickness of removed layer have been estimated. Raman-spectroscopy data show that surface irradiation with gas-cluster ions does not introduce defects into the crystalline structure of irradiated material.

Gas cluster formation during gas expansion through a supersonic nozzle with a skimmer is described. The role of the buffer zone between a pulsed valve and a nozzle in the regime of pulsed supply of working gas is shown. Influence of the working gas type on the cluster ion pulse parameters is investigated.