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Disordered tetrahedral sp3‐carbon films of different allotropic forms are grown by ion beam deposition at ≈ 120 to 200 eV carbon ion energies. The delocalized and localized electronic states of films on KCl and Al2O3 substrates are investigated by absorption and secondary radiation under N2 laser or Ar laser excitation at 90 and 300 K. A strong maximum at 6.15 to 5.80 eV (E 0β) and a threshold at 4.8 to 4.5 eV are resolved in intrinsic absorption spectra of films deposited at high currents which are tentatively attributed to direct (Γ 5+−Γ 5−) and indirect (Γ 5+−K2) transitions in partially‐ordered lonsdaleite carbon films. The disordered cubic sp3‐carbon phases obtained at low ion currents show maxima at 5.45 to 5.50 eV (Γ 25′−ΔX, indirect transition) and at about 7.0 eV (Γ 25′−Γ15, direct transition). All spectra contain low‐energy Urbach tails of different threshold energies, intensities, and slopes. A two‐component luminescence band 2.407 and 2.680 eV at 90 K under UV‐laser excitation for films with strong Urbach tails is resolved. A sample dependent “blue” emission including four well‐shaped maxima 3.031, 2.849, 2.600, and 2.480 eV at 90 K is discovered. At 90 K under strong 488.0 and 514.5 nm laser excitation of disordered carbon and polycrystalline CVD diamond films luminescence response above 4.0 eV is found.

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Low-energy ion beam deposition of thin films of tetrahedral nanocarbon (nt-C) [1] at the submolecular level in times exceeding the "thermal flash" duration can lead to the formation of 2D diamond clusters due to the structural instability of graphite allotropes [2] and the high probability of the rhombohedral graphitecubic diamond transition via C 1 s core hole Auger decay [3].At late stages of cooling of an electron-phonon subsystem, a thick low-dimension phase can grow from a "cold" and constantly replenished source of carbon subplanted at a depth of a few nanometers.In the molecular dynamics model of subplantation growth of tetrahedral carbon on amorphous substrates at the stage of "expansion" of a dense carbon phase, the effect of the crystal environment on the composition and structure of this phase was taken into account empirically based on the differences between the displacement energies of the graphite and diamond atoms and between their sputtering coefficients [4].Upon deposition of tetrahedral nanocarbon on the cleavages of single crystals that have the same symmetry as diamond, strain fields will be generated in the carbon-saturated near-surface layer in the course of the growth of a new phase due to the difference between the lattice constants of the layer and the substrate. Relaxation of these strains will give rise to misfit dislocations. Under favorable conditions, they are pure edge dislocations and form, at the surface, regular dislocation networks with a spatial period of 10-20 nm (grain boundaries with minimum surface energy [5]), which serve as the nanotemplate for quantum dot growth [6].In the Stranski-Krastanov growth model, strain relaxation promotes the development of structural instability and formation of relatively large 3D nanoislands in the growing layer [7].The cooperative growth mechanism under consideration can take place in the course of subplantation deposition of tetrahedral carbon on cubic KCl cleavages.In this work, self-organized nt-C thin layers consisting of coherent nanonetworks with a cluster size of 7-12 nm were grown on KCl(100) cleavages by ion beam deposition from a source of C +1 ions with energies of 90-180 eV and their AFM structure and stimulated recombination emission (RE) under excitation by a focused beam of an N 2 laser were studied.The procedure of complex study of the AFM relief and emission properties, as well as the design of a slit source of ions, was described in [1,8].A comprehensive AFM study of 15 films on polished glass showed the existence of dense networks of clusters with a noticeable dispersion of their sizes and positions. Motifs of clusters with a size of 6-30 nm, which have a height of 0.7-12.0 nm and a density of 3 × 10 11 -5 × 10 9 cm -2 , were resolved. The spectral composition of RE and its spatial fluctuations were the same as described in [1].Radically different results were obtained for carbon films on KCl(100) cleavages. Near-coherent surface nanomotifs with a narrow cluster-size dispersion range were resolved. This is evidence of t...

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