TY - JOUR

T1 - Mechanism of CaSi2 Synthesis Under the Electron-Beam Irradiation During Molecular-Beam Epitaxy of CaF2 on Si(111)

AU - Wang, Yuhan

AU - Kacyuba, Aleksey V.

AU - Kamaev, Gennadiy N.

AU - Zinovieva, Aigul F.

AU - Zinovyev, Vladimir A.

AU - Dvurechenskii, Anatoly V.

N1 - Wang, Y., Kacyuba, A., Kamaev, G. et al. Mechanism of CaSi2 Synthesis Under the Electron-Beam Irradiation During Molecular-Beam Epitaxy of CaF2 on Si(111). Silicon (2026). https://doi.org/10.1007/s12633-025-03628-6 The work was financially supported by Ministry of Science and Higher Education of the Russian Federation (Grant numbers FWGW-2025–0023). Author Yuhan Wang has received research support from China Scholarship Council.

PY - 2026/1/9

Y1 - 2026/1/9

N2 - In this paper, the mechanism of CaSi2 formation under electron beam irradiation during epitaxial growth of CaF2 on Si(111) substrate was discussed. The main factors controlling the efficiency of CaSi2 synthesis have been identified. This is the decomposition of the CaF2 molecule with the formation of Ca and F ions and the diffusion of silicon atoms from the substrate. Assuming that the rate-limiting process for thin films is the decomposition of the CaF2 molecule, we estimate the rate of production of calcium ions by electron irradiation at standard parameters of electron beam (an accelerating voltage of 20 keV and a current density of ≈ 0.125 mA/cm2) used in high-energy electron diffraction (RHEED) unit of our growth equipment. Results of estimation are compared with experimental data on the amount of synthesized CaSi2, obtained from atomic force microscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy. The close agreement between the experimental and estimated values confirms that CaF₂ decomposition is the primary factor controlling the CaSi2 synthesis efficiency.

AB - In this paper, the mechanism of CaSi2 formation under electron beam irradiation during epitaxial growth of CaF2 on Si(111) substrate was discussed. The main factors controlling the efficiency of CaSi2 synthesis have been identified. This is the decomposition of the CaF2 molecule with the formation of Ca and F ions and the diffusion of silicon atoms from the substrate. Assuming that the rate-limiting process for thin films is the decomposition of the CaF2 molecule, we estimate the rate of production of calcium ions by electron irradiation at standard parameters of electron beam (an accelerating voltage of 20 keV and a current density of ≈ 0.125 mA/cm2) used in high-energy electron diffraction (RHEED) unit of our growth equipment. Results of estimation are compared with experimental data on the amount of synthesized CaSi2, obtained from atomic force microscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy. The close agreement between the experimental and estimated values confirms that CaF₂ decomposition is the primary factor controlling the CaSi2 synthesis efficiency.

KW - Calcium compounds

KW - Dissociation of CaF2

KW - Electron-beam radiation

KW - Molecular-beam epitaxy

KW - Silicon

UR - https://www.scopus.com/pages/publications/105026968631

UR - https://www.mendeley.com/catalogue/03c7fa3e-e2f8-393a-a114-e88eabc44ea8/

U2 - 10.1007/s12633-025-03628-6

DO - 10.1007/s12633-025-03628-6

M3 - Article

JO - Silicon

JF - Silicon

SN - 1876-990X

ER -