Elaboration and optical properties of Sb2S3 thin films

Abstract

The group of binary chalcogenide compoundsis one of the significant groups of semiconductor compounds. The main group of metal chalcogenides, namely 𝑨𝟐 𝒗𝑩𝟑 𝒗𝑰 (A =As, Sb, Bi; B = S, Se, Te), are a class of important semiconductors that have gained immense interest owing to their optical and electrical properties. Antimony trisulfide (Sb2S3) belongs to the group V-VI compound. Over the past couple of decades, Sb2S3 thin film has elicited a lot of attention owing to their specific traits like elevated refractive index, as well as their properties of photosensitivity and thermoelectricity. The technological importance of Sb2S3 is attributed to the fact that it is used in microwave devices, electronic devices, and also optoelectronic devices. The present research includes an experimental study of sb2s3 thin films deposited by the chemical bath deposition method (CBD) on the optical properties and corresponding structural characterization. Also, studying the effect of thickness of sb2s3 films on these properties to obtain a suitable thickness with the best feature to use as an absorbent layer in photovoltaic cells. Antimony sulfide compounds were prepared by a chemical reaction between antimony chloride and the sodium thiosulfate solution, the X-ray diffraction measurements revealed that the formed sb2s3 has a crystal structure corresponding to the orthorhombic structure of a cell unit a = 1.1318, b = 0.3827, and c = 1.1218 nm. Thin films of antimony sulfide of various thicknesses (ranging in thickness between 246-470 nm) were prepared on glass substrates by CBD at room temperature. And it was found from the study of X-ray diffraction that these films are crystalline in the structure; the direction of growth in them is preferred in the crystal direction (112). This has proved that the X-ray diffraction of energy dispersed connected to the scanning electron microscope device that these films are chemically consistent. The optical properties of films prepared from antimony disulfide were studied by recording the values of transmittance and reflectance in the case of the columnar projection of light during the wavelength range of 400-2500 nm. The values of the absorption factor and gap energy were calculated, and the extent to which these constants were affected by the thickness of the membrane was studied. It also showed from the absorption coefficient analysis that the energy gap value decreases by increasing the thickness of the membrane to reach (1.45 eV) for the membrane with a thickness of 470 nm and is chemically consistent when used in photovoltaic cells.