Investigation on the Electronic Structure of Nanosized Barium Monosilicide Films Produced by Low-energy Implantation of Ba<sup>+</sup> Ions in Si

Abstract

The processes of formation of nanoscale silicide films during the implantation of Ba⁺ ions into Si (111) and Si (100) and subsequent thermal annealing were studied by electron spectroscopy. It is shown that implantation of ions with a high dose D > 10¹⁶ cm^-2 and short-term heating leads to the formation of thin films of barium monosilicide with new surface superstructures. The optimal modes of formation and band-energy parameters of BaSi films obtained by low-energy high-dose implantation of barium ions in Si are determined. It is shown that BaSi films are a narrow-gap semiconductor with a band gap of 0.7 eV and have good emission and thermoelectric properties corresponding to the solar spectrum and have high photoelectric and thermoelectric characteristics. It should be noted that, in addition to the formation of a chemical compound, the narrowing of the Si band gap upon implantation of large doses of Ba⁺ ions also contributes to defects formed as a result of strong disordering of the crystal lattice.