Electronic Structure of Single-Crystal CaF<sub>2</sub>(111) with Nanoscale Phases of Ca and Si
- 1 Department of Technology of Electronic Devices Generating, Tashkent State Technical University, Tashkent, Uzbekistan
- 2 Department of Technology of Electronic Devices Generating, Tashkent State Technical University, Tashkent, Uzbekistan
- 3 Department of Technology of Electronic Devices Generating, Tashkent State Technical University, Tashkent, Uzbekistan
Abstract
The impact of Ca and Si nano-scale structures on parameters and density of states of single-crystalline CaF 2 (111) was studied. It was shown that at low concentration of ions of Ar + (D ≤ 5 × 10 15 cm -2 ) one witnesses formation of nanoscale phases on CaF 2 surface. It was revealed that these phases lead to narrowing of the forbidden band Еg between the phases by 4 - 4.5 eV. At higher concentrations (D ≈ 6 × 10 16 cm -2 ) the surface completely is covered by Ca atoms. It was shown that deposition of θ = 10 thick Si single layer on CaF 2 surface manifests island picture. The concentration of Ca and Si nano-scale phases on the surface of CaF 2 and the band gap of the phases were investigated as a function of (h ν ) of passing light. Nano-scale phases and nano-scale films of Ca were obtained by using the technique of bombardment with ions of Ar + of CaF 2 surface. Formation of nano-scale phases were accompanied by change in the composition and structure of CaF 2 zones located between the phases. These changes led to narrowing of the forbidden band of CaF 2 down to 7.5 - 8 eV. The concentration of Ca and Si nano-scale phases on the surface of CaF 2 and the band gap of the phases were investigated as a function of (h ν ) of passing light.
- Zotov, A.V. and Saramin, А.А. (2006) Priroda. С11.
- Muradkabilov, D.M., Tashmukhamedova, D.A. and Umirzakova B.E. (2013) Applying Low-Energy Ion Implantation in the Creation of Nanocontacts on the Surface of Ultrathin Semiconductor Films. Journal of Surface Investigation. X-Ray, Synchrotron and Neutron Techniques, 7, 967-971. https://doi.org/10.1134/S1027451013050376
- Gomonyunova, M.V., Pronin, I.I., Gall, N.R., Molotsov, S.L. and Vyalix, D. (2003) Photoelectron Si 2p Spectra of Ultrathin CoSi2 layers formed on Si(100)2 × 1. Physics of the Solid State, 45, 1596-1599
- Krichevtsov, B., Gastev, S.V., Ilyushchenkov, D., Kaveev, A.K. and Sokolov, N. (2009) Magnetic Properties of Arrays of Cobalt Nanoparticles on the CaF2(110)/Si- (001) Surface. Physics of the Solid State, 51, 118-126.
- Berashevich, Y.A., Danilyuk, A.L. and Barisenko, V.E. (2002) Resonance Transfer of Charge Carriers in Si/CaF2 Periodic Nanostructures via Trap States in Insulator Layers. Semiconductors, 36, 679-684.
- Suturin, S.M., Banshchkov, A.B., Sokolov, N.S., Tyaginov, S.E. and Veksler, M. (2008) Static Current Frame Voltage Characteristics of Au/CaF2/N-Si(111) MIS Tunneling Structures.
- Ergashov, Y.S. (2017) Composition and Properties of Nanoscale Si Structures Formed on the CoSi2/Si(111) Surface by Ar+ Ion Bombardment. Technical Physics, 62, 777-780. https://doi.org/10.1134/S1063784217050103
- Smith, C.G. (1994) Low-Dimensional Quantum Devices. Reports on Progress in Physics, 59, 235. https://doi.org/10.1088/0034-4885/59/2/003
- Li, B. and Liu, J.D. (2009) CoSi2-Coated Si Nanocrystal Memory. Journal of Applied Physics, 105, Article ID: 084905. https://doi.org/10.1063/1.3110183
- Donaev, S.B., Djurabekova, F., Tashmukhamedova, D.A. and Umirzakov, B.E. (2015) Formation of Nanodimensional Structures on Surfaces of GaAs and Si by Means of Ion Implantation. Physica Status Solidi C, 12, 89-93. https://doi.org/10.1002/pssc.201400156