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The stiffness of conjugated polymers should lead to chain alignment near buried interfaces, even if the polymer film is nominally amorphous. Although simulations predict that this alignment layer is approximately 1.5 times the persistence length, chain alignment at buried interfaces of amorphous polymers has not been experimentally measured. Using Mueller matrix spectroscopy, the optical response of regiorandom poly(3-hexylthiophene-2,5-diyl) (P3HT) was modeled in order to extract the aligned layer thickness. By approximating the optical properties of the aligned layer as that of regioregular P3HT, the data can be effectively modeled. When the film is thicker than 150 nm, optical properties are best described with a 4-nm aligned layer, which is quantitatively consistent with previous predictions. 

Optical and microstructural properties of as-deposited CdTe films deposited on soda lime glass by magnetron sputtering at various source flux angles have been investigated using GIXRD, SEM, unpolarized transmittance / reflectance, and spectroscopic ellipsometry. Influence of deposition angle on resultant crystalline grain size and orientation are tracked for these films. All CdTe films studied are found to have cubic crystal structure and (111) preferential grain orientation. Films deposited at 0° and 45° are almost entirely (111) oriented, whereas films deposited at higher angles exhibit a wider variety of competing grain orientations, suggesting that deposition angle can be used as an effective parameter towards controlling grain orientation. With increasing numbers of grain orientations, grain size is found to decrease. Ex-situ spectroscopic ellipsometry is used to obtain the structural and optical properties. Stress induced in the film is calculated based on shifts of critical point energies.