In this study, WO3 and NiO thin films were deposited on the ITO/Glass substrates by radio frequency (RF) magnetron sputtering, respectively. The physical and electrochromic properties of thin films were investigated. On the other hand, the lithium perchlorate (LiClO4) powder was dispersed in propylene carbonate (PC) solvent to complete 1 M electrolyte. Then, as the 4.5 wt.% of ethyl cellulose and 8 wt.% ethylene carbonate (EC) were added to this electrolyte under stirring, a gel polymer electrolyte (GPE) was formed. Finally, the WO3 and NiO thin films obtained with the optimal deposition parameters were combined with the GPE to set up a complementary electrochromic device (CECD). The effects of the various coloring voltages on the electrochromic properties of CECD are investigated. The memory effect, energy-saving efficient, response time and switch lifetime of CECD are also estimated and discussed. Experimental results reveal that the amorphous thin films can be obtained with the RF power of 100 W and oxygen concentration of 60% at room temperature (RT). The thicknesses of WO3 and NiO films were approximately 530 nm and 180 nm, respectively. The stoichiometric of thin films were 2.99 for O/W ratio and 1.01 for O/Ni ratio. The GPE [(1 M LiClO4+PC)+ethyl cellulose(4.5 wt.%)+EC(8 wt.%)] exhibits a viscosity coefficient of 100 mPa∙s, a maximum ion conductivity (£m) of 7.17 mS/cm, a minimum activation energy (Ea) of 0.033 eV and a average visible transmittance of 82% at RT. The optimal electrochromic CECD (Glass/ITO/WO3/GPE/NiO/ITO/Glass) biased with a coloring/bleaching voltage of ¡Ó2.2 V revealed a transmittance variation (£GT%) of 54.53%, an optical density change (£GOD) of 0.790, an intercalation charge (Q) of 6.28 mC/cm2 and a coloration efficiency (£b) of 125.21 cm2/C at a wavelength (£f) of 550 nm. The chromaticity coordinates of CECD were x=0.289 and y=0.365 under the colored state. In addition, the energy-saving efficient of CECD was 15.19 W/V-m2 over the wavelength range between 380 nm and 780 nm. Also, it presented an open-circuit memory effect that the colored transmittance (£f at 550 nm) was 18.9% in 24 h. The total response time of the CECD was about 4 s for coloring and bleaching steps. After the repeated switch of 1,000 times, the £GT% of CECD was 43.57%. In this study, WO3 and NiO thin films with good adhesion, amorphous, and nearly stoichiometric were successfully deposited by RF sputter. Furthermore, high £m and high transmittance of GPE can be prepared easily and inexpensively. Our results demonstrated that the CECD exhibited the advantages of low applied voltage, high £b, fast response time and long-term memory characteristics.

The roles of hydrogen induced defects in pure ZnO has been studied extensively. However, in a transition metal, such as Co, doped ZnO thin films the effect of hydrogen in electric conduction and magnetic coupling is still unclear and needs further study. Recently model predicts that hydrogen can be a shallow donor as well as an agent to induce ferromagnetism coupling between two adjacent Co ions which substitute the Zn sites at room temperature in a ZnO sample with a high Co doping ratio. However, the experimental supports is rare. In this study, Co-doped(5%) ZnO films are grown by a RF-magnetron sputtering system on glass substrate at room temperature. The growth condition is fixed for RF power in 200W, working press of 70 mtorr and various mixing ratio of H2/Ar+H2 gas. The crystal structure, electric and optical properties and the influence of vacuum annealing on the samples are studied. In this research, we found that the doping of hydrogen in Co-doped ZnO thin films truly increases the electric conductivity which is proportional to the H2/(Ar+H2) ratio. When the ratio of hydrogen is low, the (002) peak taken by a Glazing Angle X-ray Diffractometer dominates, while increasing hydrogen ratio other diffraction peaks appear, indicating an enhancement of crystal structure in all directions, and grain sizes and unit cell volume decrease. From the optical transmittance measurement, it is found that the color of films turned into metallic like and the optical band gap increases linearly with H2 ratio which can be attributed to the Burstein-Moss effect that corresponds to the increasing of carriers in the conduction band by doping of H2. The transmittance data provides the information of the ratio of crystalline and amorphous, which can also be correlated to the AFM results. When the H2 ratio is higher than 30%, more crystals and larger sizes of grains were formed in the films, such that carriers did not need to pass grain boundaries so frequently and experienced less scattering that was actually improve the electric conductivity. The electric conductivity can be even improved by post annealing in H2 environment. Moreover, the Magnetic circular dichroism (MCD) measurement shows that the Co2+ ions does truly substitute on Zn sited in Td symmetry during thin film deposition. The resistance measurement as a function of temperature found the hydrogenated Co-doped thin films are semiconductor conductive. More works are needed to determine the magnetization, identify second phases and Vo by SQUID and X-ray photoelectron spectroscopy.

In this research, the amorphous/nanocrystalline ZrCu/Cu multilayered thin films with various conditions such as individual layer thickness, total layer thickness, and interface type have been successfully fabricated by the multi-gun sputtering processes. To investigate the mechanical properties and deformation behaviors of substrate-supported ZrCu/Cu multilayered thin films, these films deposited on the Cu or polyimide foils were prepared for tensile testing. Firstly, the tensile behaviors of the monolithic ZrCu thin film metallic glass and the ZrCu/Cu multilayered thin films deposited on the pure Cu foils are systematically examined. The extracted tensile modulus and strength of the 1-£gm-thick multilayered thin films are in good agreement with the theoretical iso-strain rule of mixture prediction. The extracted 2-£gm-thick multilayered film data are lower, but can be corrected back by considering the actual intact cross-sectional area during the tensile loading. Moreover, the current results reveal that the ZrCu/Cu multilayered coating exhibit much better tensile performance than the monolithic ZrCu coating. It indicates that the amorphous/nanocrystalline multilayered thin film structure can certainly enhance the mechanical properties of monolithic thin film metallic glasses under tension. Secondly, for the further investigation of tensile response, the polyimide-supported amorphous/nanocrystalline ZrCu/Cu multilayered thin films with various individual layer thicknesses from 10 to 100 nm were prepared. The relatively soft, smooth, and flexible polyimide foils as the substrates in this experiment can undergo sufficient deformation under In this research, the amorphous/nanocrystalline ZrCu/Cu multilayered thin films with various conditions such as individual layer thickness, total layer thickness, and interface type have been successfully fabricated by the multi-gun sputtering processes. To investigate the mechanical properties and deformation behaviors of substrate-supported ZrCu/Cu multilayered thin films, these films deposited on the Cu or polyimide foils were prepared for tensile testing. Firstly, the tensile behaviors of the monolithic ZrCu thin film metallic glass and the ZrCu/Cu multilayered thin films deposited on the pure Cu foils are systematically examined. The extracted tensile modulus and strength of the 1-£gm-thick multilayered thin films are in good agreement with the theoretical iso-strain rule of mixture prediction. The extracted 2-£gm-thick multilayered film data are lower, but can be corrected back by considering the actual intact cross-sectional area during the tensile loading. Moreover, the current results reveal that the ZrCu/Cu multilayered coating exhibit much better tensile performance than the monolithic ZrCu coating. It indicates that the amorphous/nanocrystalline multilayered thin film structure can certainly enhance the mechanical properties of monolithic thin film metallic glasses under tension. Secondly, for the further investigation of tensile response, the polyimide-supported amorphous/nanocrystalline ZrCu/Cu multilayered thin films with various individual layer thicknesses from 10 to 100 nm were prepared. The relatively soft, smooth, and flexible polyimide foils as the substrates in this experiment can undergo sufficient deformation under tension. The modulus and strength of the multilayered thin film are again demonstrated to be consistent with the theoretical iso-strain rule of mixture values. As the individual layer thickness decreases from 100 to 10 nm, the Young¡¦s moduli are only varied slightly. However, the maximum tensile stress exhibits a highest value for the 25 nm layer thickness. The higher crack spacing, or the lower crack density, of this 25 nm multilayer film leads to the highest strength. Thirdly, to avoid the stress and strain incompatibility owing to the mismatch of elastic modulus and strength levels from the connected amorphous/nanocrystalline layers, the Cu-supported amorphous/nanocrystalline ZrCu/Cu multilayered thin films with sharp and graded interfaces were successfully sputtered and examined by tensile testing. The extracted tensile properties of the multilayered films can be compared with the predicted values based on the two-phase and three-phase iso-strain rule of mixture model. The multilayered films with graded interfaces, each about 50 nm thick, consistently exhibit higher tensile strength and elongation. This can be rationalized by the reduced stress and strain incompatibility along the interfaces.

The electro-optical properties of the ZnO/Si heterojunction embedded with self-assembled gold nanoparticles on patterned silicon substrate are investigated in this master thesis. High quality n-type ZnO film is deposited on patterned p-type silicon substrate by radio-frequency sputtering to form a ZnO/Si pn junction. The patterned silicon substrates are prepared by ICP-RIE using self-assembled nickel metal dot and silicon dioxide as etching mask. The optimum ICP process conditions of silicon nanopillars are CF4/Ar ~ 40/40 sccm and bias/RF power 400/400 W. Silicon nanopillars of diameter ~ 50 nm and height 100~400 nm are formed on the substrate surface. ZnO film is then deposited of a growth rate ~ 12 nm/min at the substrate temperature = 200oC. The plasmonic effects on the electro-optical properties, including photoluminescence (PL), reflection, and electrical characteristics, are studied by adding self-assembled gold nanoparticles within the ZnO film. The self-assembled gold nanoparticles are formed by thermal deposition and rapid thermal annealing at 700oC. The gold nanoparticles are observed by scanning electron microscopy (SEM) and particles of diameter about 100 nm. The PL intensity of ZnO is enhanced more than ten times at the peak wavelength = 380 nm by adding the gold nanoparticles and silicon nanopillars. Strong blue emission light could be saw with the naked eyes. For the electric characteristics, self-assembled gold nanoparticles in patterned ZnO/Si heterojunction show photoelectric conversion phenomenon because of high electromagnetic absorption and plasmonic effects.

It is well known that thermally evaporated a-As2S3 thin films are prone to oxidation when exposed to an ambient environment. These As2O3 crystals are a major source of scattering loss in sub-micron optical integrated circuits. Magnetron sputtering a-As2S3 not only produces films that have optical properties closer to their equilibrium state, the as-deposited films also show no signs of photo-decomposed As2O3. The TM propagation loss of the as-deposited As2S3-on-Ti:LiNbO3 waveguide is 0.20 plus/minus 0.05 dB/cm, and it is the first low loss hybrid waveguide demonstration. Using the recipe developed for sputtering As2S3, a hybrid Mach-Zehnder interferometer has been fabricated. This allows us to measure the group index of the integrated As2S3 waveguide and use it in the study of the group velocity dispersion in the sputtered film, as both material dispersion and waveguide dispersion may be present in the system. The average group index of the integrated As2S3 waveguide is 2.36 plus/minus 0.01. On-chip optical amplification was achieved through thermal diffusion of erbium into X-cut LiNbO3. The net gain measured for a transverse magnetic propagation mode in an 11 μm wide Er:Ti:LiNbO3 waveguide amplifier is 2.3 dB plus/minus 0.1 dB, and its on-chip gain is 1.2 plus/minus 0.1 dB/cm. The internal gain measured for a transverse electric propagation in an 7 μm wide Er:Ti:LiNbO3 waveguide amplifier is 1.8 dB plus/minus 0.1 dB and is among the highest reported in the literature. These gains were obtained with two 1488 nm lasers at a combined pump power of 182mW. In order to increase further the on-chip gain, we have to improve the mode overlap between the pump and the signal. This can be done by doping erbium into As2S3 film using multi-layer magnetron sputtering. The Rutherford backscattering spectroscopy shows that the doping of Er:As2S3 film with 16 layers of erbium is homogeneous, and Raman spectroscopy confirms no significant amount of Er-S clusters in the sputtered film. The deposition method was used to fabricate an Er:As2S3 waveguide, and the presence of active erbium ions in the waveguide is evident from the green luminescence it emitted when it was pumped by 1488 nm diode laser.

Abstract Recently, titanium dioxide¡]TiO2¡^ is one of the most extensively studied transition-metal oxides because of its remarkable photocatalyst efficiency and electronic properties. In this paper, thin films ware obtained by dual ion beam sputtering. By different processes, these samples can be classified into three categories. Firstly, thin films, deposited on 200 mash copper grids for 15 minutes, were investigated that many TiO grains is about 5 nm in size by transmission electron microscopy¡]TEM¡^. Next, TiO2 thin films, sputtered on si wafers and glass for 180 minutes in an O2 environment by using titanium target, were initially identified by X ray diffraction instrument¡]XRD¡^. The result shows that some thin films have good orientations. By TEM, TiO2 grains on bottom of films are about 20 nm. By scanning electron microscopy¡]SEM¡^, TiO2 grains on the surface are about 1~2 £gm in size and are oblong in shape. The last, TiO thin films were directly deposited on si wafer for 180 minutes in no O2 environment by using titanium target and then annealed to transform from TiO to TiO2. By XRD, the thin film, annealed at 600¢J for 1hr, has good orientation. By TEM, TiO2 grains, annealed at 1000¢J for 24hr, grow up to 1-2 £gm in size and are oblong in shap.

Applications of semiconductor nanocrystal in electronics are promising. Various techniques were developed to synthesize and analyze semiconductor nanocrystals for integrated circuit applications. In this study, silicon and germanium nanocrystals were synthesized in silicon dioxide matrix by magnetron sputtering deposition and following high temperature furnace annealing. Multilayer and single layer samples were prepared by co-sputtering depositions. Transmission electron microscopy measurements were carried out to analyze annealing effects on nanocrystal size distribution, change in shape, density and localization in silicon dioxide (SiO2). Ge-Ge Traverse Optical (TO) peak was monitored using Raman spectroscopy to investigate germanium nanocrystal formation and stress effects of silicon dioxide. Si-O-Si asymmetric stretching band is examined by Fourier transform infrared transmission spectroscopy to study silicon dioxide matrix recovery with germanium nanocrystal formation. Luminescence characteristics of silicon nanocrystals in visible and near infrared region (550nm-1050nm) with changing nanocrystal size and density were studied with photoluminescence spectroscopy.

In this study, silicon (Si) rich silicon dioxide (SiO2) films and terbium (Tb) embedded in three different Si containing films has been produced by e-beam evaporation and magnetron sputtering techniques. Post deposition annealing was done for different temperatures and durations to study its effect on both Si nanocrystal formation and Tb luminescence. It was verified by X-ray diffraction technique (XRD) that Si nanocrystals were formed in Si rich matrices. Energy dispersive X-ray (EDS) spectroscopy analysis was carried out to determine the relative concentrations of the atoms inside the produced films. X-ray photoelectron spectroscopy (XPS) gave the evidence of different bonding structures inside the Tb-Si-O containing films. Depth profile measurements were carried out to analyze changes in the relative concentration during sputtering of the layers after annealing of the Tb containing film. Luminescence characteristics of Si nanocrystals and Tb3+ ions were studied by photoluminescence (PL) spectroscopy. It was observed that Tb3+ luminescence enhanced by an energy transfer from Si nanocrystals and trap levels in a matrix. This result supplies valuable information about the excitation paths of Tb3+ ion the way of intense luminescence.

This thesis describes the works done during the design and deposition process of the antireflection coating for the materials commonly used as refractive optical elements in thermal imaging systems. These coatings are quite necessary to reduce reflection losses from the surface of the optics and stray light that directly affects the image quality. Germanium, zinc sulfide and zinc selenide were used as substrate material and their optical properties were investigated with infrared ellipsometry and FTIR. Antireflection coatings for each material operating in 8-12 &amp / #956 / m range were designed with Needle Synthesis Technique. In order to shorten the optimization time, commercial software / &ldquo / The Essential Macleod&rdquo / was used. In order to reduce the reflectance losses multilayer structure was used in the coating design, and zinc selenide and lead telluride were used as low and high index materials. In this study the necessary theoretical background and common deposition techniques are reviewed. Samples were produced using the magnetron sputtering. To optimize the v thicknesses of the deposited layers, growth period and rate was controlled. Thicknesses of the samples, following to the deposition were also measured by thickness profilometer. A 3-layer coating, PbTe/ZnSe/PbTe, on ZnS and 2-layer coating PbTe/ZnS on Ge having more than 90% transmittance in 9.7-10.3 &amp / #956 / m wavelength region have been successfully produced. Although, the measured range for 3 and 2- layer coating is narrower than the aimed one, it has been shown that, the method developed in this thesis would yield AR-coatings with broader spectral response if a system having better control on deposition parameters is used. For example, our design and optimization work has suggested that a 7-layer AR coating on germanium, with alternating high and low index layers is expected to give transmittance value greater than 93% in the studied wavelength region.

A novel high-k gate dielectric material, i.e., hafnium-doped tantalum oxide (Hf-doped TaOx), has been studied for the application of the future generation metal-oxidesemiconductor field effect transistor (MOSFET). The film's electrical, chemical, and structural properties were investigated experimentally. The incorporation of Hf into TaOx impacted the electrical properties. The doping process improved the effective dielectric constant, reduced the fixed charge density, and increased the dielectric strength. The leakage current density also decreased with the Hf doping concentration. MOS capacitors with sub-2.0 nm equivalent oxide thickness (EOT) have been achieved with the lightly Hf-doped TaOx. The low leakage currents and high dielectric constants of the doped films were explained by their compositions and bond structures. The Hf-doped TaOx film is a potential high-k gate dielectric for future MOS transistors. A 5 àtantalum nitride (TaNx) interface layer has been inserted between the Hf-doped TaOx films and the Si substrate to engineer the high-k/Si interface layer formation and properties. The electrical characterization result shows that the insertion of a 5 àTaNx between the doped TaOx films and the Si substrate decreased the film's leakage current density and improved the effective dielectric constant (keffective) value. The improvement of these dielectric properties can be attributed to the formation of the TaOxNy interfacial layer after high temperature O2 annealing. The main drawback of the TaNx interface layer is the high interface density of states and hysteresis, which needs to be decreased. Advanced metal nitride gate electrodes, e.g., tantalum nitride, molybdenum nitride, and tungsten nitride, were investigated as the gate electrodes for atomic layer deposition (ALD) HfO2 high-k dielectric material. Their physical and electrical properties were affected by the post metallization annealing (PMA) treatment conditions. Work functions of these three gate electrodes are suitable for NMOS applications after 800°C PMA. Metal nitrides can be used as the gate electrode materials for the HfO2 high-k film. The novel high-k gate stack structures studied in this study are promising candidates to replace the traditional poly-Si-SiO2 gate stack structure for the future CMOS technology node.