Characterization of thin films from reflection and transmission ellipsometric parameters

Abstract

Spectroscopic ellipsometry is a powerful tool for characterization of thin films / surfaces. To simultaneously extract optical constant and film thickness from ellipsometric parameters ψ and Δ, dispersion models of material’s refractive index and spectroscopic ellipsometry measurement have been often required. In this work, we propose an extraction method of optical parameters of thin films from the reflection and transmission ellipsometric parameters. This method necessitates neither spectroscopic information of ψ and Δ, nor dispersion models. Verification measurements were carried out with the single-point and imaging ellipsometers, respectively.

The wave mechanics for microwave absorption film-Part 3: Film with multilayers

“…( 18) reduces to s11(k) or RL(xk-1 -) and the input impedance Zin(k, xk -) reduces to that for WMB or MB. However, the input impedance of WMB or MB are usually applied wrongly to the intermediate layer [43,[56][57][58][59][60][61][62].…”

“…Since there is no suitable theory for the middle layers in the film shown by Fig. 1, the results of MB [43,56,57] and WMB [58][59][60][61][62] are often misapplied to layer k. It should be especially noted that beam bk + 1 is not considered in the conventional treatment of WMB but needs to be considered in layer k. Suitable treatment has been developed here for the first time from transmission line theory. It should also be noted that the flawed QWM should also not be applied to the multilayer system.…”

“…Similar to the hierarchical structures with different interface organizations, multilayer film has been investigated for better microwave absorption [55][56][57][58][59][60][61][62][63][64][65][66][67][68]. Even though each layer k in the film shown in Fig.…”

Reflection and transmission ellipsometry measurement under incoherent superposition of light

“…To obtain ellipsometric parameters spectra, ellipsomicroscopy measurement is repeated wavelength-by-wavelength [3]. Here, we employ reflection and transmission ellipsometry [4][5][6][7][8] for optical parameters extraction from single measurement at a single wavelength and a single incident angle. In reflection and transmission ellipsometry [8], the optical constant and thickness of thin films were extracted simultaneously from the reflection and transmission ellipsometric parameters -∆ 𝑟 ,  𝑟 , ∆ 𝑡 ,  𝑡 -, which were measured by the instrument at reflection and transmission configurations, respectively.…”

“…Here, we employ reflection and transmission ellipsometry [4][5][6][7][8] for optical parameters extraction from single measurement at a single wavelength and a single incident angle. In reflection and transmission ellipsometry [8], the optical constant and thickness of thin films were extracted simultaneously from the reflection and transmission ellipsometric parameters -∆ 𝑟 ,  𝑟 , ∆ 𝑡 ,  𝑡 -, which were measured by the instrument at reflection and transmission configurations, respectively. Transmission ellipsometry is limited to the use of the transparent substrates, and therefore, backside reflections of the substrate affect the results, for both reflection [7,9,10,11,12] and transmission ellipsometry measurements.…”