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Nickel-Titanium (Ni-Ti) thin films have gained a lot of attention due to their unique features, such as the shape memory effect. Micro-actuators, micro-valve, micro-fluid pumps, bio-medical applications, and electronic applications have a lot of interest in these smart thin films. Sputter-deposited NiTi thin films have shown the potential to be very useful as a powerful actuator in micro-electro-mechanical systems (MEMS) because of their large recovery forces and high recoverable strains. Despite the advancement of improved deposition methods for the NiTi thin films, there are still certain unsolved challenges that impede accurate composition control throughout the deposition process. Many applications, spanning from the aerospace industries to a range of nanotechnologies, require knowledge of the sputtering characteristics of the materials that are subjected to bombardment, ejection, and deposition of ions. In recent decades, atomic scale modeling has been given a high emphasis in ion sputtering research, providing an adequate and precise description of collision cascades in solids using the Stopping and Range of Ions in Matter (SRIM) and Transport of Ions in Matter (TRIM). In this paper, SRIM is used to address how the heavy ions interact with the target materials. A variety of ion-solid interaction characteristics, including the sputter yield, have been determined by simulating collision cascades in the solids. On the other hand, TRIM was used to describe the range of ions that enter into the matter and cause damage to the target throughout the process. The simulation was carried out to compare the sputtering yield of Ni and Ti by varying the energy input (from 300V to 1300V). SRIM simulation was conducted by varying the thickness of the film, the angle of incidence of ions, and the energy involved in the sputtering process. The characterization of the films has been carried out using Field Emission Scanning Electron Microscopy (FESEM) to comprehend the surface and interface morphologies of the films and to validate the simulated results. With an increase in energy input (target voltage), the sputtering yield increased. The sputtering yield of the Ni target was higher than the Ti target indicating that Ni can be removed relatively easier than Ti.

In this study, TiO₂ coatings are deposited on Si(100) wafers by direct current pulsed magnetron sputtering technology. The crystal structure of TiO₂ coatings gradually transforms from the anatase phase to the amorphous phase when the sputtering power is decreased from 900W to 150W. Besides, the growth surface temperature of TiO₂ coatings decreases from 630${}^{\circ }$C to 241${}^{\circ }$C. The relationship between the growth behavior and growth surface temperature of TiO₂ coatings is investigated using the dynamic scaling theory. The results show that in the first stage, the growth behavior of TiO₂ coatings gradually transforms from the Frank–van der Merwe mode to the Volmer–Weber mode with decreasing sputtering power from 900W to 150W. In the second stage, the growth behavior of TiO₂ coatings gradually transforms from the Stranski–Krastanov mode to the Volmer–Weber mode. Transformation of the growth behavior of TiO₂ coatings in the second stage transforms the crystal structure of TiO₂ coatings from the anatase phase to the amorphous phase.

Parallel molecular dynamics simulation study of the ion-surface collision system is reported. A sequential molecular dynamics simulation program is converted into a parallel code utilizing the concept of parallel virtual machine (PVM). An effective and favorable algorithm is developed. Our parallelization of the algorithm shows that it is more efficient because of the optimal pair listing, linear scaling, and constant behavior of the internode communications. The code is tested in a distributed memory system consisting of a cluster of eight PCs that run under Linux (Debian 2.4.20 kernel). Our results on the collision system are discussed based on the speed up, efficiency and the system size. Furthermore, the code is used for a full simulation of the Ar–Ni(100) collision system and calculated physical quantities are presented.

The aim of the present work is the optimization of the Si/buffer-layer/YBCO multilayer deposition process so as to grow superconducting films of quality suitable for device applications. The structural properties of the Si/CeO₂ system, obtained by RF magnetron sputtering of CeO₂ targets in Ar atmosphere, have been studied. More than 50 films have been deposited and some of them submitted to post-deposition annealing treatments both in N₂ and O₂ atmospheres. The presence of an unwanted amorphous SiO₂ layer at the Si/CeO₂ interface compromises the YBCO c-axis orientation, and therefore the sharpness of the R versus T transition.

A newly designed deposition system has been realized: it has been specially conceived for obtaining bi- and tri-layers, adopting two targets in YSZ and CeO₂, respectively. Results on YSZ/Si and CeO₂/YSZ/Si systems obtained with the new machine are presented and discussed: (100) oriented YSZ films with nominal thickness of 40 nm have been obtained. The CeO₂ film subsequently deposited has the desired (100) orientation. The YBCO film, in the final YBCO/YSZ/CeO₂/Si configuration, is c-axis oriented.

To develop high-quality film device with good reliability, it is often essential to be able to evaluate the parameters such as stress, the biaxial elastic modulus, and coefficient of thermal expansion (CTE) of film. Based on the stress measurement in situ during the thermal cycle by laser scanning method, two techniques were used to measure the biaxial elastic modulus and CTE of BaTiO₃ films deposited on substrate. The value of the biaxial elastic modulus and CTE for BaTiO₃ films determined from two methods is close, in which the biaxial elastic modulus of BaTiO₃ films is higher than that of corresponding bulk while the CTE of BaTiO₃ films is a little smaller than that of bulk material.

We report the experimental observations of large spatially disk-shaped patterns in an iron (Fe) film system deposited on silicone oil surfaces by a DC-magnetron sputtering method. These disk patterns form spontaneously during deposition and grow successively in vacuum condition after deposition. Their nucleation, growth and evolution are strongly dependent on the sputtering power, deposition period and growth time. The experiment indicates that they may result from the spontaneous organization and gathering of the Fe atoms and atomic clusters driven by the internal stress.

In this study, titanium dioxide (TiO₂) thin films were deposited on unheated glass substrates using an unbalanced magnetron sputtering system with different deposition times of 25, 35 and 45 min, respectively. The structure and surface morphology of TiO₂ thin films were characterized by atomic force microscopy (AFM) and transmission electron microscopy (TEM) with selected-area electron diffraction (SAED). It was found that the crystallite size of TiO₂ thin films was in the range of 10–20 nm, and the surface roughness was 1–3 nm. The SAED patterns show that the phase of TiO₂ thin films obtained in this study is anatase phase.

Ta–Si–N thin films and Cu/Ta–Si–N thin films were deposited on p-type Si (111) substrates by magnetron reactive sputtering. Then the films were characterized by four-point probe sheet resistance measurement, atomic force microscopy, X-ray diffraction method and scanning electron microscope, respectively. The experimental results show that the sheet resistance of Ta–Si–N thin film increases with N content. And the surface roughness of the thin film first decreases and then increases with N content. By increasing the N content, the diffusion barrier property of Ta–Si–N thin film can be improved; however, this improvement is not evident when N content beyond 56%. The as-deposited Ta–Si thin film is nano-crystalline. When doped with N, the as-deposited thin film becomes amorphous. The crystallization of Ta–Si–N thin film occurs again at high temperature. Cu atoms diffuse through grain boundaries of Ta–Si–N thin film into Si, and this leads to failure of the diffusion barrier.

Ultra-thin platinum (Pt) films were deposited on Si(100) substrates at 160°C by magnetron sputtering and subsequently annealed to form silicides. The thickness of the Pt_xSi films was found to be approximately 4 nm as determined by transmission electron microscopy (TEM). X-ray photoelectron spectroscopy (XPS) analysis shows that these films consist of PtSi and Pt₂Si phases, and a multi-layer configuration of SiO_x/PtSi/Pt₂ Si/Si was detected by angle-resolved XPS. However, the Pt₃Si phase was not detected by X-ray diffraction (XRD).

Bilayers of Sm–Co/Fe have been fabricated on 70 nm Cr buffered Si(100) substrate at an elevated temperature of 650^°C by the help of DC and RF magnetron sputtering. Very thin layers (0–0.7 nm) of Ti were introduced at the interface of the Sm–Co and Fe phases. The samples were analyzed by X-ray diffraction (XRD) and alternating gradient magnetometer (AGM). All the samples showed strong exchange coupling and single phase behavior. The rise and fall in magnetization and energy product were observed with increasing Ti interlayer thickness. Energy product (BH)_max value was found increased by 44% for 0.2 nm Ti interlayer as compared to the sample without Ti layer at interface.

In this study, we show that by applying appropriate deposition conditions, Zn nanostructured templates for the growth of zinc oxide (ZnO) nanowires can be fabricated, from which ultrafine high optical quality nanowires can be grown by means of post-deposition low-temperature oxidation. By identifying and optimizing the appropriate parameters, we successfully fabricated long ultrafine ZnO nanowires up to 30 microns in length and 50 nm in diameter. Our report contradicts the commonly held paradigm that sputter deposition can only be used to fabricate thin films with no significant nanostructure morphology and provides a low cost, high throughput method of fabricating different ZnO nanostructures. The studies of photoluminescence (PL) of the nanowires showed their high optical quality with band edge dominated emission with small defect-related input.

InSb-based devices embedded in the human body can be utilized for biological applications, including the detection of biomagnetic fields owing to the high electron mobility of InSb, which is a suitable magnetic resistance element. In this study, the aqueous stability of In${}_{0.57}$Sb${}_{0.43}$/quartz prepared by RF magnetron sputtering was evaluated as the initial stage for use in biomedical devices. In${}_{0.57}$Sb${}_{0.43}$/quartz was coated with (3-mercaptopropyl) trimethoxysilane (MPT), as InSb was not stable under aqueous conditions. MPT coating did not affect the thin-film properties (such as surface morphology, crystal structure, and electrical properties) of In${}_{0.57}$Sb${}_{0.43}$/quartz. A cell viability assay confirmed the lower cytotoxicity of MPT-coated In${}_{0.57}$Sb${}_{0.43}$/quartz than that of bare In${}_{0.57}$Sb${}_{0.43}$/quartz because the MPT coating reduces the elution of indium from In${}_{0.57}$Sb${}_{0.43}$/quartz. In addition, the MPT coating essentially suppressed the deterioration of the thin-film properties under simulated physiological conditions. Therefore, MPT-coated InSb thin films are expected for use in temporary implanted biomedical devices.

Understanding the behavior of excess Ga is important for fabrication methods that employ the sputtering of GaSb-based materials. This is due to the comparatively low vapor pressure of Ga, which can result in GaSb becoming Ga-rich under experimental conditions. In this study, the growth and characterization of nonstoichiometric polycrystalline GaSb thin films with excess Ga, grown by RF magnetron sputtering, are reported. Ga content was adjusted by mixing N₂ in the Ar sputtering gas. The structural properties indicate that the grown thin films maintain the zinc blend structure of GaSb, and have an induced tensile strain along a direction parallel to the substrate. Excess Ga segregates towards the film surface and forms micro/nanoclusters. The internal tensile strain and the Ga cluster formation have little effect on the intrinsic properties of GaSb. These findings could lead to the fabrication of GaSb-based thin films using sputtering with excellent mass productivity.

Cobalt thin films deposited by radio frequency sputtering were investigated. Microstructures of the Co films were analyzed by XRD and TEM. The results show that films microstructure varies with the variation of the sputter gas pressure P_Ar. Magnetic properties measured by VSM show that all the films possess relatively high saturation magnetization 4πM_s, and strong in-plane uniaxial magnetic anisotropy field H_k. Co films deposited below 0.3 Pa show soft magnetic properties and its microwave permeability was measured by vector network analyzer in the 0.1–5 GHz range.

Hydrogenated amorphous SiC films (a-Si_1-xC_x:H) were prepared by DC magnetron sputtering technique on p type Si(100) and corning 9075 substrates at low temperature, by using 32 sprigs of silicon carbide (6H-SiC). The deposited film a-Si_1-xC_x:H was realized under a mixture of argon and hydrogen gases. The (a-Si_1-xC_x:H) films have been investigated by scanning electronic microscopy equipped with EDS system (SEM-EDS), X-rays diffraction (XRD), secondary ions mass spectrometry (SIMS), Fourier transform infrared spectroscopy (FTIR), UV-visible-IR spectrophotometry, and photoluminescence (PL). XRD results showed that the deposited film was amorphous with a structure of a-Si_0.81C_0.19:H corresponding to 19 at.% carbon. The photoluminescence response of the samples was observed in the visible range at room temperature with two peaks centered at 463 nm (2.68 eV) and 542 nm (2.29 eV). The structural properties and the origin of the luminescence were discussed.

At room temperature, titanium dioxide (TiO₂) films were deposited by the direct current pulse magnetron sputtering technique. Varying O₂/Ar flow ratio, TiO₂ films with different nanocrystalline structures were obtained. The high resolution transmission electron microscopy results show that with O₂/Ar = 6/14, the nanocrystalline in rutile phase appears in as-deposited film. Then X-ray diffraction patterns of annealed films revealed that with O₂/Ar = 6/14, the higher weight fractions of rutile TiO₂ appear in films. The optical emission spectroscopy results show that with O₂/Ar < 6/14, O element was mainly existed as O^-/O⁺ ions, instead of excited state of O atoms.

During the sputtering-deposition process, the temperature of film growth surface is more important than that of the substrate, which could seriously influence the film growth behavior. While, it is difficult to measure the temperature of film growth surface, because of the low space resolution of traditional temperature measurement systems. In this paper, the temperature of TiO₂ film growth surface and substrate were monitored by the home-made NiCr/NiSi film thermocouple and standard NiCr/NiSi K type wire thermocouple. With the same sputtering parameters, the temperature of TiO₂ film growth surface could reach $846.2\pm 3.9^{\circ }$C. While, the temperature of substrate was only about $305.8\pm 1.4^{\circ }$C. Finally, combining the temperature of film growth surface in sputtering-deposition process, the film growth behavior can be investigated and controlled in future.

Indium tin oxide (ITO) is widely used in the optoelectronic industry as a transparent conductive oxide owing to its excellent optical and electrical properties. To improve the physical properties of ITO, highly conductive ITO/Ag/ITO multilayer electrodes were prepared using radio frequency (RF) magnetron sputtering at room temperature. Then, laser annealing was performed on the multilayer electrodes with scanning intervals of 0.01, 0.02, 0.05 and 0.1 mm. The structural properties of the multilayer electrodes were characterized by X-ray diffraction, and their optical and electrical properties were characterized by ultraviolet (UV) visible spectrophotometry and a four-point probe station, respectively. The results demonstrated that the multilayer films had a polycrystalline structure, and ITO (222) and Ag (111) preferred orientations were identified after laser annealing. In addition, the crystalline size of the Ag layers increased slightly, implying that the defect density within the Ag layers was reduced, resulting in a significant increase in its conductivity. A significantly low electrical resistivity of 5.35 $\mathrm{\Omega }$/sq and high optical transmittance of 85% were achieved. The Haacke index value was ${\varphi }_{\mathrm{\text{Vis}}}\cong 37.74\times 10^{-3}{\mathrm{\Omega }}^{-1}$, which was much better than the value of ${\varphi }_{\mathrm{\text{Vis}}}\cong 18.14\times 10^{-3}{\mathrm{\Omega }}^{-1}$ before laser annealing.

In this paper, Cu thin films were successfully deposited on glass substrates using DC magnetron sputtering at varying deposition times. The deposition time was varied as 5, 9, 11 and 17min. The obtained Cu thin films were analyzed for morphology and topography using atomic force microscopy (AFM). The size of the surface structures/grains was seen to evolve with deposition time. The conventional/statistical, fractal and multifractal analyses were carried out on AFM images using existing imaging algorithms. The arithmetic roughness and interface width parameters were seen to evolve with the sputtering time. The autocorrelation and height–height correlation functions revealed that the surfaces of all the Cu thin films exhibited self-affine character, but were not mounded properties. The fractal dimensions computed using box counting and power spectral density functions revealed that larger dimensions were associated with larger surface features. The lacunarity coefficients were too small indicating that the surfaces were generally deficient in porosity and other defects. The multifractal analyses revealed that spatial roughness does not exhibit linear relationship with the deposition time. The study reveals that surface evolution and nanoscale behavior is significantly influenced by the deposition time although a linear relationship is not established.

Recently [M. Kunat et al., Surf. Sci.474, 114 (2001)] a quenching of adsorbate-assisted adsorption ("autocatalytic adsorption") by defects has been observed for the system CO/Cu(110). A conceptually similar effect for CO adsorption on O–Ir(110) had additionally been reported before [U. Burghaus et al., Surf. Sci.384, L869 (1997)]. Presented is a simple Monte Carlo simulation (MCS) scheme which includes basically one free fit parameter and can reproduce both effects consistently.