Optical and Photoelectric Properties of Planar Structures Obtained by Thermal Annealing of Ga₂S₃ Plates in Zn Vapors

Abstract

Ga2S3 single crystals have been obtained by chemical vapor transport (CVT) in iodine vapors. The Ga2S3 compound was synthesized from Ga and S taken in stoichiometric quantities. The compound has been subjected to long term thermal annealing (TA) at the temperatures of 850 and 1070 K for 6 to 60 h in Zn vapors. After TA the natural surface of Ga2S3 single crystals contain a cover layer. The photoluminescence, photoconductivity and electrical conductivity of this layer depend on treatment conditions (temperature and duration). Electrical conductivity of these samples is 3–5 magnitude orders higher than for untreated crystals. The treated single crystals contain both Ga2S3 and ZnS crystallites. Thermal annealing of Ga2S3 crystals in Zn vapors leads to shifting of fundamental absorption edge toward low energies and absorption coefficient increase in the spectral region of 2.4–3.0 eV.

Glassy GaS: transparent and unusually rigid thin films for visible to mid-IR memory applications

“…The derived optical band gap g = 2.34 eV is very similar to that for crystalline GaS, 2.50 eV, 26 and remarkably lower than g for Ga2S3 polymorphs, 2.74 eV ≤ g ≤ 3.30 eV. [63][64][65] A characteristic feature of chalcogenide glass thin films is their ability to change optical, structural and chemical properties under light irradiation with photon energy close to g . 66 A shift of the fundamental absorption edge, a change of the optical constants or different etching rates in alkaline solutions are only few examples of photo-structural transformations, used for photolithographic processes, creation of diffraction gratings, Bragg reflectors, etc.…”

Optical and Photoelectric Properties of Nanolamellar Structures Obtained by Thermal Annealing of InSe Plates in Zn Vapours

“…The thermal annealing (TA) of gallium and indium monochalcogenides in normal atmosphere, or in oxygen‐enriched atmosphere, leads to the formation of their crystalline micro and nanocomposites with In 2 O 3 and Ga 2 O 3 oxides . As we demonstrated in our previous works, crystalline composites consisting of A II B VI and A III B VI semiconductors, with physical properties characteristic for these compounds, can be obtained by TA of the A III B VI (GaS, GaSe, GaTe and InSe) and semiconductors (e.g., Ga 2 S 3 ) in Cd and Zn vapours …”

State-of-the-art surface oxide semiconductors of liquid metals: an emerging platform for development of multifunctional two-dimensional materials

“…Ga 2 S 3 is a p-type semiconductor which has been developed previously with a nanometre scale thickness using deposition techniques. [232][233][234][235][236][237] The 2D Ga 2 S 3 lm was synthesized by the sulphurization of the surface oxide lm of liquid gallium. 236,237 In general, the Ga 2 O 3 lm was delaminated from the surface of liquid gallium in the ambient atmosphere.…”