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TiO2: 2%Sm3+ thin films were prepared by oblique angle deposition. X-ray diffraction (XRD), scanning electron microscope (SEM), UV-Vis-NIR spectrophotometer, fluorescence spectrophotometer was employed to characterize the structure and optical properties of TiO2: 2%Sm3+ thin films. The results indicated that these thin films were with anisotropic columnar structure before and after calcination. The optical anisotropy measured by transmission difference (Tp-Ts) at 500nm was increasing from 8% to 33% with calcination. Under ultraviolet excitation (λex = 330nm) and commercial 365nm UV lamp excitation, these TiO2: Sm3+ thin films show intense 4G5/2→ 6H5/2, 7/2, 9/2 emissions of Sm3+. The polarized photoluminescence was anticipated in the anisotropic thin films.

The antimony doped tin oxide (SnO 2 :Sb) (ATO) thin films were prepared by oblique angle electron beam evaporation technique. X-ray diffraction, field emission scanning electron microscopy, UV–vis–NIR spectrophotometer and four-point probe resistor were employed to characterize the structure, morphology, optical and electrical properties. The results show that oblique angle deposition ATO thin films with tilted columns structure are anisotropic. The in-plane birefringence of optical anisotropy is up to 0.035 at α = 70°, which means that it is suitable as wave plate and polarizer. The electrical anisotropy of sheet resistance shows that the sheet resistance parallel to the deposition plane is larger than that perpendicular to the deposition plane and it can be changed from 900 Ω/□ to 3500 Ω/□ for deposition angle from 40° to 85°, which means that the sheet resistance can be effectively tuned by changing the deposition angle. Additionally, the sandwich structure of SiO 2 buffer layer plus normal ATO films and oblique angle deposition ATO films can reduce the resistance, which can balance the optical and electrical anisotropy. It is suggested that oblique angle deposition ATO thin films can be used as transparent conductive thin films in solar cell, anti-foggy windows and multifunctional carrier in liquid crystal display.

VO2 (M) STF through reduction of V2O5 STF was prepared. The results illustrate that V2O5 STF can be successfully obtained by oblique angle thermal evaporation technique. After annealing at 550 °C/3 min, the V2O5 STF deposited at 85° can be easily transformed into VO2 STF with slanted columnar structure and superior thermochromic properties. After deposition SiO2 antireflective layer, Tlum of VO2 STF is enhanced 26% and ΔTsol increases 60% compared with that of normal VO2 thin films. Due to the anisotropic microstructure of VO2 STF, angular selectivity transmission of VO2 STF is observed and the solar modulation ability is further improved from 7.2% to 8.7% when light is along columnar direction. Moreover, the phase transition temperature of VO2 STF can be depressed into 54.5 °C without doping. Considering the oblique incidence of sunlight on windows, VO2 STF is more beneficial for practical application as smart windows compared with normal homogenous VO2 thin films.