Production and characterization of Se₈P₂ semiconductor alloy

This work presents a study about the production characterization of the chalcogenic amorphous Se₈P₂ alloy. The Mechanical Alloying technique was used to prepare the alloy, and some of its physical properties were characterized using EXAFS, x-ray diffraction (XRD), Raman spectroscopy techniques and also techniques based on the photoacoustic effect. Structural simulations based on the Reverse Monte Carlo (RMC) method were also performed. The use of EXAFS measurements and the total structure factor obtained from x-ray diffraction measurements in RMC simulations allowed the determination of structural properties of Se₈P₂, such as average coordination numbers and interatomic distances, bondangle distribution functions and the partial distribution functions gij(r). EXAFS and XRD also confirmed the amorphization of the alloy. The RMC simulations also provided information about the relative frequency of interatomic pairs. The vibrational modes of Se₈P₂ were obtained using Raman spectroscopy. Two setups were used to obtain information using the photoacoustic effect, the open photoacoustic cell and the setup for photoacoustic spectroscopy measurements. Through them the thermal diffusivity and the optical gap of Se₈P₂ were obtained. (author)