Analysis of errors in thin-film optical parameters derived from spectrophotometric measurements at normal light incidence

Abstract

A comparative analysis is made of the errors in deriving the optical parameters (n, refractive index; k, absorption coefficient; d, film thickness) of thin films from spectrophotometric measurements at normal light incidence. The errors in determining n, k, and d by the (TR(f)R(b)), (TR(f)R(m)), (TR(b)R(m)), (TR(f)), (TR(m)), and T(k = 0) methods are compared. It is shown that they are applicable to optical constants of thin films in the n > 1.5, k < 4.5, and d/lambda = (0.02-0.3) range, and their combinations make possible the determination of n and k to an accuracy of better than ?4%. To derive the optical constants in a wide spectral range with high accuracy and isolate the correct physical solutions reliably, one should apply all methods, using the relevant solutions with the lowest errors, as shown in this research, when determining the optical constants of As(2)S(3) and Sb(2)Se(3) films.

Thin Chalcogenide Films for Photonic Applications

“…We have demonstrated that the spectrophotometric and ellipsomeric methods offer a good accuracy for determination of the optical parameters of thin chalcogenide films from /30 to 2 ( is working wavelength) (Konstantinov et al 1998, Babeva et al 2001, Todorov et al 2010a. Results on the reflectance response of photonic crystals from chalcogenide glass/polymer (DeCorby et al, 2005;Kohoutek et al, 2007a) or chalcogenide glass/chalcogenide glass, e.g.…”

“…8. The Swanepoel's method (Swanepoel, 1983) was used for optical constants determination of the thin films with d > 300 nm and a combination of double (T, R) and triple (T, R, R) methods was applied in calculations for thinner layers (d < 300 nm) (Konstantinov et al, 1998;Babeva et al 2001). The calculated values for optical parameters of thin films show that their refractive index is independent on the layer's thickness for d > 50 -70 nm (Fig.…”

Optical Properties of RF Sputtered Samarium Oxide Thin Films

“…Whereas both of E o and E dis increase with pressure of the gas. The disagreement between ε L and ε ∞ may be due to free carriers' contribution [52].…”

Investigation on micro structural, mechanical and tribological properties of aluminium nitride (aln) coating deposited by rf magnetron sputtering

“…The peaks of uncoated, RT, 200˚C, 400˚C, 500˚C, 600˚C, was compared with Origin eight and Match! Natural phenomenon patterns from the determined peaks admire the formation of hexaagonal section of AlN were indexed to stay with plane figure structure [4,22].…”