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In this study, indium–tin oxide (ITO)/Nb-doping TiO2 (TNO) double-layer transparent conductive oxide (TCO) films deposited using DC magnetron sputtering were used as a surface anti-reflection layer with an overall thickness of 100 nm for double-layer films. The simulated results showed that ITO and TNO thickness combinations of 90 nm/10 nm, 80 nm/20 nm, and 70 nm/30 nm had a higher transmittance and lower reflectance than others in the visible wavelength range. Compared to the single-layer ITO films, for ITO/TNO films deposited on the glass and silicon substrates with an optimum thickness of 80/20 nm, the reflectance was reduced by 5.06% and 4.63%, respectively, at the central wavelength of 550 nm and crystalline silicon photo response wavelength of 900 nm. Moreover, the near-infrared reflectance of the double-layer ITO/TNO with thickness combinations of 90 nm/10 nm, 80 nm/20 nm, and 70 nm/30 nm, when deposited on silicon substrates, was obviously improved by the graded refractive index lamination effect of air (1)/ITO (1.98)/TNO (2.41)/Si (3.9). [ABSTRACT FROM AUTHOR]

Mg[F.sub.2] films with a columnar microstructure are obliquely deposited on glass substrates by resistive heating evaporation. The columnar angles of the films increases with the deposition angle. Anisotropic stress does not develop in the films with tilted columns. The residual stresses in the films depend on the deposition and columnar angles in a columnar microstructure. OCIS codes: 310.6870, 310.4925, 310.1860.

Ta--Si oxide composite thin-film rugate filters were prepared by radio frequency ion-beam sputtering and their residual stress and substrate deflections were measured. The residual stress and substrate deflection of these composite film rugate filters were less than that of notch filters made from a series of discrete quarter-wave layers with alternate high and low indices because of the smooth modulation of composition and no interface structure of the rugate filter. OCIS codes: 310.6870, 310.1620.

Titanium oxide films were prepared by ion-beam-assisted deposition on glass substrates at various substrate temperatures. The effect of the temperature of thermal annealing from 100 [degrees]C to 300 [degrees]C on the optical properties and residual stress was investigated. The influence on the stoichiometry and residual stress of titanium oxides deposited at different substrate temperature was discussed. The residual-stress was minimum and the extinction coefficient was maximum at an annealing temperature of 200 [degrees]C with a substrate temperature of 150 [degrees]C. However, when the substrate temperature was increased to 200 [degrees]C and 250 [degrees]C, the residual stress was minimum and the extinction coefficient was maximum at an annealing temperature of 250 [degrees]C. The spectra of x-ray photoelectron spectroscopy reveal that the films lost oxygen and slowly generated lower suboxides at the annealing temperature at which the residual stress was minimum and the extinction coefficient was maximum. As the annealing temperature increased above the temperature at minimum stress, the lower suboxides began to capture oxygen and form stable oxides. [Ti.sup.O.sub.2] films deposited at substrate temperatures of 200 [degrees]C and 250 [degrees]C were more stable than films deposited at 150 [degrees]C. OCIS codes: 310.3840, 310.6860, 310.6870.

Titanium oxide thin films were deposited by electron-beam evaporation with ion-beam-assisted deposition. The effect of the substrate temperature and annealing temperature on the columnar microstructure and recrystallization of titanium oxide was studied. The values of the refractive index varied from 2.26 to 2.4, indicating that the different substrate temperatures affected the film density. X-ray diffraction revealed that all films were amorphous as deposited. At annealing temperatures from 100[degrees]C to 300[degrees]C, only the anatase phase was formed. As the substrate temperature increased from 150[degree]C to 200[degrees]C to 250[degrees]C, the recrystallization temperature fell from 300[degrees]C through 250[degrees]C to 200[degrees]C. Changing the substrate temperature resulted in the formation of various types of columnar microstructure, as determined by scanning-electron microscopy. Different columnar structures resulted in different surface morphologies, as measured by atomic-force microscopy. OCIS codes: 310.3840, 310.6860, 310.6870.

The effects of thermal annealing of titanium oxide films deposited by ion-beam assistance at annealing temperatures from 100 [degrees]C to 300 [degrees]C on the residual stress and optical properties of the films was investigated. The refractive indices and extinction coefficients increased gradually as the temperature was increased from 100 [degrees]C to 200 [degrees]C and then declined gradually as the temperature was increased further from 200 [degrees]C to 300 [degrees]C. The film lost oxygen and slowly generated lower suboxides as the annealing temperature was reduced below 200 [degrees]C, as determined by x-ray photoelectron spectroscopy (XPS). As the annealing temperature increased above 200 [degrees]C, the lower suboxides began to capture oxygen and form stable oxides. XPS measurements were made to verify both the binding energy associated with the Ti 2p line and the variation of the O 1s line. A Twyman-Green interferometer was employed for phase-shift interferometry to study the residual stress. The residual stress declined as the temperature was reduced from 100 [degrees]C to 200 [degrees]C because the lower suboxides reduced the stress in the film. Above 200 [degrees]C, the film began to capture oxygen, so the residual stress rose. At 300 [degrees]C, the film was no longer amorphous as the anatase was observed by x-ray diffraction. OCIS codes: 310.3840, 310.6860, 310.6870.

Both three-layer (Ti[O.sub.2]-Ag-Ti[O.sub.2]) and five-layer (Ti[O.sub.2]-Ag-Ti[O.sub.2]-Ag-Ti[O.sub.2]) heat mirrors with optimum transmission in the visible and good reflectance in the IR have been designed by admittance diagram techniques. The mirrors were fabricated successfully by optical monitoring. An interesting anomalous layer was found and explained, and its equivalent refractive index and thickness are 2.015 - i0.016 and 2.56 nm, respectively. Key words: Transparent heat mirror, optical monitoring, admittance diagram, ion-assisted deposition, anomalous layer.

An aspherical mirror is made by a thin-film coating technique. A special mask is placed between the evaporation source and the substrate that is to be coated as an aspheric. The design principle of the mask is fully described. An ion-assisted deposition technique is used to relieve aluminum film stress and to increase surface reflectance. The final wave front is tested by conventional interferometric methods for aspherics. Less than one-fifth of a wave (632.8 nm) of spherical aberration is achieved without much trial and error.

This study investigated the impacts of structure, optical and electrical properties of indium-gallium-zinc oxide (IGZO) film with varied ZnO deposition powers on glass substrates by using cosputtering system with two radio-frequency (RF) (ZnO and GaO) and one direct-current (DC) (InO) magnetron. The average transmittance decreased obviously from 86.37 to 81.44 % and the optical energy gap decreased from 3.56 to 3.29 eV when ZnO deposition power increases. Results are ascribed to facts that the content of Zn in IGZO films was increased and the fitting extinction coefficient near the wavelength in the range of 370-450 nm obviously increased with increase of ZnO deposition power; the fitting refractive index of IGZO films was noticeably increased and surface morphology displayed a dense structure. The crystallinities of IGZO films reveal from an amorphous structure with a content of Zn less than 50 at.% to a polycrystalline phase of IGZO film with a content of Zn around 70.5 at.%. The residual stress of the indium gallium oxide (IGO) films with undoped ZnO content significantly changed from a tensile stress to a compressive stress with an increased annealing temperature. When the ZnO composition incorporated into the IGO film, variations of the residual stress in the films gradually become smaller. The optimum process condition of cosputtering IGZO films with a ZnO deposition power at 100 W and an annealing temperature at 300 °C showed the largest film mobility, smallest surface roughness, and a lower residual stress. [ABSTRACT FROM AUTHOR]

ABSTRACT This work presents a novel refractive index sensor structure based on surface plasmon resonance, consisting of planar glass plates coated with multilayer thin film. The glass plate guides the light, the multilayer metallic thin film excites the surface plasmon wave, and the dielectric film is used to fine tune the resonance wavelength. The resolution and spectrum variation and the wavelength shift, for aqueous solutions of salt of various concentrations, are measured. The sensor resolution and sensitivity is obtained. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:3009-3012, 2014 [ABSTRACT FROM AUTHOR]

(WO3)100−XCX thin films (x \(=\) 0−9.3 at%) were cosputtered on indium-tin-oxide glass substrate with W and C targets by reactive dc magnetron sputtering at room temperature. The effects of doped C on the microstructure and optical properties of the (WO3)100−XCX thin film were examined by field emission scanning electron microscopy with energy dispersive X-ray spectroscopy, X-ray diffraction, and a spectrophotometer. It was found that all of the as-deposited films were amorphous. The average transmittances of bleaching and colored WO3 film in the 400–700 nm range were 75% and 65.9%, respectively. The variation in average transmittance of the bleaching and colored states of (WO3)90.7C9.3 film was 68.3%. The average transmittance of bleaching (WO3)100−XCX thin films did not vary with C doping. However, the average transmittance of colored (WO3)100−XCX film decreased to <48% after C doping. In addition, the optical transmittance contrast of (WO3)100−XCX thin films was found to be suitable for blue laser wavelength recording. [ABSTRACT FROM PUBLISHER]

Abstract: The TiVCrZrTaN thin film was prepared on Si substrate at 300°C by reactive RF magnetron sputtering deposition. Effects of applied dc bias (from 0V to 120V) on the microstructure, residual stress, and hardness properties of TiVCrZrTaN films were investigated by field emission scanning electron microscopy, X-ray diffraction, Fizeau interferometer and nanoindentation system. The columnar structures are observed by field emission scanning electron microscopy. X-ray diffraction analysis reveals that TiVCrZrTaN films were polycrystalline and have preferred orientation along (111) when applied dc bias was below 100V. The preferred orientation is changed from (111) to (200) as applied dc bias was 100V. The residual stress of all films was compressive stress. The average grain size and hardness of the films were investigated as a function of applied dc bias. The minimum average grain size and maximum hardness of TiVCrZrTaN film with applied dc bias 100V were 6.1nm and 30.9GPa, respectively. In this work, the presented results illustrate that the optimum properties of TiVCrZrTaN films can be obtained at applied dc bias in the range of 50V to 120V. [Copyright &y& Elsevier]

A measuring apparatus based on a phase shifting interferometry technique to determine the mechanical properties of metal oxide films was presented. Thin films were prepared by ion-beam sputter deposition at low substrate temperature. Quantitative determination of the mechanical properties such as the internal stress, biaxial elastic modulus, and thermal expansion coefficient of metal oxide films were investigated. A phase shifting Twyman-Green interferometer with the phase reduction algorithm was setup to measure the temperature-dependent stress in thin films. Two types of circular glass plates, with known Young's moduli, Poisson's ratios, and thermal expansion coefficients, were used as coating substrate. The temperature-dependent stress behavior of the metal oxide films was obtained by heating samples in the range from room temperature to 70 °C. The stresses of thin films deposited on two different substrates were plotted against the stress measurement temperature, showing a linear dependence. Four oxide films were reported for their film stresses and thermal expansion coefficients. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A new technique for determining the stress of thin films is described. This technique combines digital phase shifting interferometry with image-processing software. A circular disc polished on one side is used as the coated substrate during film deposition. The average stress in thin films can be derived by comparing the deflection of the substrate before and after film deposition. The deflection of the substrate by the deposited film is obtained by the phase map. Using the Zernike polynomial fitting algorithm, a three dimensional contour map is generated from the polynomial coefficients to visualize the deformation of the thin film and to examine the tensile or compressive stress after film deposition. Four oxide films prepared by ionbeam sputter deposition are investigated for their film stresses. The experimental results show that the stress values are concordant with measurements using other methods. [ABSTRACT FROM AUTHOR]

In this study, WO3–Nb2O5 electrochromic films and an ITO/WO3–Nb2O5/Nb2O5/NiVOx/ITO all-solid-state electrochromic device were deposited using fast-alternating bipolar-pulsed magnetron sputtering using tungsten and niobium targets. The influence of different sputtering powers from the niobium target on the refractive index, extinction coefficient, optical modulation, coloration efficiency, reversibility, and durability of the WO3–Nb2O5 films is discussed. The aim of this work is to find the suitable Nb proportion to increase durability and less negative effect in the electrochromic performance of Nb2O5-doped WO3 films. The lifetime of the WO3–Nb2O5 films is 4 times longer than pure WO3 films when the sputtering power of the Nb target is higher than 250 W. The results show that WO3–Nb2O5 composite films used for an all-solid-state electrochromic device can sustain over 3 × 104 repeated coloring and bleaching cycles while the transmission modulations can be kept above 20%. The coloring and bleaching response times are 7.0 and 0.7 s, respectively. [ABSTRACT FROM AUTHOR]

We proposed a simple design method based on a scanning search algorithm for obtaining an acceptable wide-angular universal visible (vis) antireflection (AR) coating design with the incident angles over the range 0–30° for different glass substrates having refractive indices ranging from 1.472 to 1.750. We then applied AR-coating to seven different glass substrates in the same deposition run using ion-assisted deposition. It was shown that the measured and calculated wide-angular universal vis AR effects were in agreement, where the total average vis reflectances at angles 0 and 30° for the practical AR-coated substrates can be effectively reduced from 5.92 and 6.09% (uncoated substrates) to below 0.25 and 0.34%, respectively, which are comparable to the calculated reflectance values of 0.22 and 0.33%, revealing that an acceptable wide-angular universal vis AR performance can be obtained. [ABSTRACT FROM AUTHOR]

A normal-incidence universal broadband visible antireflection (AR) coating design, suited for commonly used glass substrates with refractive indices ranging from 1.472 to 1.750, was simulated using a spiral search approach, and then seven different substrates were coated simultaneously in one single deposition run to reduce their visible spectral reflectances by ion-assisted deposition. It was shown that the universal visible AR coating design of various substrates with refractive indices of 1.472, 1.517, 1.552, 1.619, 1.672, 1.718, and 1.750, obtained using the spiral search algorithm of a 2-material 10-layer system, was simplified to an 8-layer design, and the total average visible reflectance of practical AR-coated substrates was reduced from 5.55% for uncoated substrates to below 0.340%; the universal visible AR performance was found suitable. Moreover, this normal-incidence universal broadband visible AR coating also revealed an acceptable wide-angle visible antireflective effect for an incident angle range of 0–30°. [ABSTRACT FROM AUTHOR]

A wide-angle and wideband visible (vis) antireflection (AR) coating with the incident angles ranging from 0–50° was designed for a flexible poly(ether sulfone) (PES) substrate, based on a scanning search method, and then this wide-angular vis AR coating was fabricated by the ion-assisted deposition technique. It was found that not only the wide-angular vis AR performance in the designed range was acceptable, but also its vis reflectance for incident angles beyond the designed range was reduced to lower than that of the uncoated substrate, revealing an omnidirectional wideband vis antireflective effect. [ABSTRACT FROM AUTHOR]

A synthesis method based on a recurrent circling search algorithm is proposed for obtaining a very low loss normal-incidence broadband visible (vis) or near-infrared (NIR) antireflection (AR) coating design. Its design algorithm is quite simple and straight, and a fairly high resultant AR performance can also be achieved. It is shown that the mean residual reflectance of a broadband vis AR coating design in the range of 400–750 nm and a broadband NIR AR coating design in the range of 800–1600 nm, obtained by the recurrent circling search method using a two-material system, can be reduced to below 0.035 and 0.063%, respectively. [ABSTRACT FROM AUTHOR]

Titanium oxide (TiO2) thin films were prepared by ion-assisted deposition (IAD) on glass substrates at various substrate temperatures. These films were re-baked and at the temperature of re-crystallization. The effects of the stability of the films on their optical properties, residual stress and surface roughness were studied. The evolution of oxidation and the cause of the variation in the optical properties and residual stress during baking and re-baking were discussed. However, the optical constants, residual stress and surface roughness varied less in re-baking than in baking. During both baking and re-baking, at substrate temperatures of 150 °C, the extinction coefficients, residual stress and surface roughness fluctuated more than at substrate temperatures of 200 and 250 °C. These results all reveal that TiO2 films were more stable after re-baking than after baking, and it was especially useful for the IAD films deposited at substrate temperature of 150 °C. [ABSTRACT FROM AUTHOR]

In this study, we present a numerical design approach, based on a vibrating search algorithm, to design a very low-loss normal-incidence broadband visible (vis) or near-infrared (NIR) antireflection (AR) coating. The vibrating search method involves the vibration adjustment and vibration-eliminating operations, which are utilized successively to improve the AR performance and simplify the design structure. Not only is the design algorithm very simple, the resultant broadband AR performance is also relatively good. The mean spectral reflectances of the AR coating designs in the visible region, 400–750 nm, and in the NIR region, 800–1600 nm, for a two-material multilayer system and obtained by the vibrating search method, can be reduced below 0.040 and 0.064%, respectively. [ABSTRACT FROM AUTHOR]

This paper reports on the application of a phase shifting interferometry technique for the concurrent measurement of the thermal expansion coefficient αand the elastic modulus E/1-&upsi;of Ta[sub 2] O[sub 5] thin film. The Ta[sub 2] O[sub 5] films were prepared by ion beam sputter deposition. The stresses in the thin films were measured with the phase shifting interferometry technique using two types of circular discs with known thermal expansion coefficients, Young's moduli and Poisson's ratios. The temperature-dependent stress behaviour of Ta[sub 2] O[sub 5] films was obtained by heating samples in the range from room temperature to 70°C. The internal stresses of Ta[sub 2] O[sub 5] thin films deposited on the BK-7 and Pyrex glass substrates were plotted against the stress measurement temperature, showing a linear dependence. From the slopes of the two lines in the stress versus temperature plot, the thermal expansion coefficient and the elastic modulus of Ta[sub 2] O[sub 5] thin film are then calculated. [ABSTRACT FROM AUTHOR]