Optical properties of selenium

There are several approaches to analyze transmittance data of selenium films, from which one can extract their optical constants and other related topics.^[1]

However, the algebraic method of Swanepoel seems to be trustful and need no dispersion relations in prior, but is limited to transmittance spectra that display a number of peaks (maxima and minima).^{[2] [3]}

The following paper deals with conventional curve-fitting of the transmittance data, an approach that depends on the availability of proper dispersion formulas to be inserted in the program.^[4]

Stoichiometric films of selenium-based alloys such as those of Bi-Se and Bi-Te composites are of technical importance for applications in memory switch devices. Thermoanalytical studies often give information about their stoichiometry, melting/boiling points and kinetic reactions responsible for their decomposition and crystallization. A preliminary thermoanalytical study on Bi-Se composites were conducted via thermogravimetry (TG) and differential thermogravimetry (DTG) experiments using a single heating rate and analyzing the measured non-isothermal TG and DTG curves via model-based kinetic reaction formulas of original Coats-Redfern (CR) and Achar-Brindley-Sharp (ABS) equations, as described in the following paper, though it is always preferable to analyze such TG and DTG data on the basis of model-free kinetic reaction formulations and several heating rates.^[5]

A number of studies were carried out on undoped amorphous and crystalline selenium films, in which their structure and electric/dielectric properties/data have been also investigated and analyzed, a few of them are listed in the references below.^{[6] [7] [8]}

References

1. Jafar, Mousa M. Abdul-Gader; Saleh, Mahmoud H.; Ahmad, Mais Jamil A.; Bulos, Basim N.; Al-Daraghmeh, Tariq M. (2016-04-01). "Retrieval of optical constants of undoped amorphous selenium films from an analysis of their normal-incidence transmittance spectra using numeric PUMA method". Journal of Materials Science: Materials in Electronics. 27 (4): 3281–3291. doi:10.1007/s10854-015-4156-z. ISSN 0957-4522.
2. Saleh, Mahmoud H.; Ershaidat, Nidal M.; Ahmad, Mais Jamil A.; Bulos, Basim N.; Jafar, Mousa M. Abdul-Gader (2017-06-01). "Evaluation of spectral dispersion of optical constants of a-Se films from their normal-incidence transmittance spectra using Swanepoel algebraic envelope approach". Optical Review. 24 (3): 260–277. doi:10.1007/s10043-017-0311-5. ISSN 1340-6000.
3. "Comprehensive formulations forthe total normal-incidence optical reflectance and transmittance of thin films laid on thick substrates". ResearchGate. Retrieved 2017-11-06.
4. Saleh, Mahmoud H.; Jafar, Mousa M. Abdul-Gader; Bulos, Basim N.; Al-Daraghmeh, Tariq M. F. (2014-10-21). "Determination of Optical Properties of Undoped Amorphous Selenium (a-Se) Films by Dielectric Modeling of Their Normal-Incidence Transmittance Spectra". Applied Physics Research. 6 (6): 10. doi:10.5539/apr.v6n6p10. ISSN 1916-9647.
5. Ahmad, Mais Jamil A.; Jafar, Mousa M. Abdul-Gader; Saleh, Mahmoud H.; Shehadeh, Khawla M.; Telfah, Ahmad; Ziq, Khalil A. (2017-09-30). "Evaluation of Kinetic Parameters and Thermal Stability of Melt-Quenched Bi_xSe_100−x Alloys (x ≤7.5 at%) by Non-Isothermal Thermogravimetric Analysis". Applied Microscopy. 47 (3). doi:10.9729/AM.2017.47.3.110. ISSN 2287-5123.
6. Abdul-Gader Jafar, M. M.; Nigmatullin, R. R. (2001-09-21). "Identification of a new function model for the AC-impedance of thermally evaporated undoped selenium films using the Eigen-coordinates method". Thin Solid Films. 396 (1): 282–296. doi:10.1016/S0040-6090(01)01166-X.
7. ABDUL-GADER, M. M.; AL-BASHA, MAHMOUD A.; WISHAH, K. A. (1998-07-01). "Temperature dependence of DC conductivity of as-deposited and annealed selenium films". International Journal of Electronics. 85 (1): 21–41. doi:10.1080/002072198134328. ISSN 0020-7217.
8. I.F., Al-Hamarneh,; B.N., Bulos,; Abdul-Gader, Jafar, M.M. "Effect of isothermal annealing and visible-light illumination on the AC-impedance behavior of undoped selenium thin films". Journal of Non-Crystalline Solids. 355 (4–5). ISSN 0022-3093.