Exploring negative ion behaviors and their influence on properties of DC magnetron sputtered ITO films under varied power and pressure conditions

We deposited indium-tin-oxide(ITO)films on silicon and quartz substrates by magnetron sputtering technology in pure argon.Using electrostatic quadrupole plasma diagnostic technology,we investigate the effects of discharge power and discharge pressure on the ion flux and energy distribution function of incidence on the substrate surface,with special attention to the production of high-energy negative oxygen ions,and elucidate the mechanism behind its production.At the same time,the structure and properties of ITO films are systematically characterized to understand the potential effects of high energy oxygen ions on the growth of ITO films.Combining with the kinetic property analysis of sputtering damage mechanism of transparent conductive oxide(TCO)thin films,this study provides valuable physical understanding of optimization of TCO thin film deposition process.

Periodic transparent nanowires in ITO film fabricated via femtosecond laser direct writing

This paper reports the fabrication of regular large-area laser-induced periodic surface structures(LIPSSs)in indium tin oxide(ITO)films via femtosecond laser direct writing focused by a cylindrical lens.The regular LIPSSs exhibited good properties as nanowires,with a resistivity almost equal to that of the initial ITO film.By changing the laser fluence,the nanowire resistances could be tuned from 15 to 73 kΩ/mm with a consistency of±10%.Furthermore,the average transmittance of the ITO films with regular LIPSSs in the range of 1200-2000 nm was improved from 21%to 60%.The regular LIPSS is promising for transparent electrodes of nano-optoelectronic devices-particularly in the near-infrared band.

High-performance omnidirectional self-powered photodetector constructed by CsSnBr_(3)/ITO heterostructure film

Omnidirectional photodetectors attract enormous attention due to their prominent roles in optical tracking systems and omnidirectional cameras.However,it is still a challenge for the construction of high-performance omnidirectional photodetectors where the incident light can be effectively absorbed in multiple directions and the photo-generated carriers can be effectively collected.Here,a high-performance omnidirectional self-powered photodetector based on the CsSnBr_(3)/indium tin oxide(ITO)heterostructure film was designed and demonstrated.The as-fabricated photodetector exhibited an excellent self-powered photodetection performance,showing responsivity and detectivity up to 35.1 mA/W and 1.82×10^(10) Jones,respectively,along with the smart rise/decay response time of 4 ms/9 ms.Benefitting from the excellent photoelectric properties of the CsSnBr_(3) film as well as the ability of the CsSnBr_(3)/ITO heterostructure to efficiently separate and collect photo-generated carriers,the as-fabricated photodetector also exhibited an excellent omnidirectional self-powered photodetection performance.All the results have certified that this work finds an efficient way to realize high-performance omnidirectional self-powered photodetectors.

Properties of Reactive Magnetron Sputtered ITO Films without in-situ Substrate Heating and Post-deposition Annealing

Indium tin oxide (ITO) films were prepared on polyester, Si and glass substrate with relatively high deposition rate of above 0.9 nm/s by DC reactive magnetron sputtering technique at the sputtering pressure of 0.06 Pa system, respectively. The dependence of resistivity on deposition parameters, such as deposition rate, target-to-substrate distance (TSD), oxygen flow rate and sputtering time (thickness), has been investigated, together with the structural and the optical properties. It was revealed that all ITO films exhibited lattice expansion. The resistivity of ITO thin films shows significant substrate effect: much lower resistivity and broader process window have been reproducibly achieved for the deposition of ITO films onto polyester rather than those prepared on both Si and glass substrates. The films with resistivity of as low as 4.23 x 10^-4 Ω.cm and average transmittance of ～78% at wavelength of 400～700 nm have been achieved for the films on polyester at room temperature.

Fabrication of Hydrogenated Microcrystalline Silicon Thin Films at Low Temperature by VHF-PECVD

Using H 2 diluted silane,series of μc Si∶H films are fabricated at low temperature with VHF PECVD.The thickness measurements reveal that the deposition rates are obviously enhanced with higher plasma excitation frequency or working pressure,but increase firstly and then decrease with the increase of plasma power density.Raman spectra show that the crystallinity and the average grain sizes of the films strongly depend on the temperature of substrate and the concentration of silane.However,the plasma excitation frequency only has effect on the crystallinity,and a maximum occurs during the further increase of plasma excitation frequency.From XRD and TEM experiments,three preferential crystalline orientations (111),(220) and (311) are observed,and the average grain sizes are different for every crystalline orientation.

ITO Film应用于投射式电容触控面板的趋势分析

薄膜式投射电容及玻璃式投射电容是投射电容式触控面板的两种主要技术。当前随着ITOGlass的供不应求,越来越多的厂商投身于ITO Film技术的开发与应用。文章主要介绍了两种投射电容式触控技术的现况、优缺点及未来市场发展趋势。

Characterization and analysis of DLC films with different thickness deposited by RF magnetron PECVD

Diamond-like carbon (DLC) films have excellent mechanical and chemical properties similar to those of crystalline diamond giving them wide applications as protective coatings. So far, a variety of methods are employed to deposit DLC films. In this study, DLC films with different thicknesses were deposited on Si and glass substrates using RF magnetron PECVD method with C 4 H 10 as carbon source. The bonding microstructure, surface morphology and tribological properties at different growing stages of the DLC films were tested. Raman spectra were deconvoluted into D peak at about 1370 cm 1 and G peak around 1590 cm 1 , indicating typical features of the DLC films. A linear relationship between the film thickness and the deposition time was found, revealing that the required film thickness may be obtained by the appropriate tune of the deposition time. The concentration of sp 3 and sp 2 carbon atoms in the DLC films was measured by XPS spectra. As the films grew, the sp 3 carbon atoms decreased while sp 2 atoms increased. Surface morphology of the DLC films clearly showed that the films were composed of spherical carbon clusters, which tended to congregate as the deposition time increased. The friction coefficient of the films was very low and an increase was also found with the increase of film thickness corresponding to the results of XPS spectra. The scratch test proved that there was good bonding between the DLC films and the substrates.

Tuning optical properties of ITO films grown by rf sputtering:Effects of oblique angle deposition and thermal annealing

Indium tin oxide(ITO)thin films were prepared using the technique of rf-sputtering with oblique angle deposition(OAD).The films were as-deposited and thermally treated at 250℃.The combination of substrate inclination and annealing was used for modifying morphological and structural properties that lead to changes of the optical properties.The resulting films show morphology of tilted nanocolumn,fissures among columns,and structural changes.The as-deposited films are structurally disordered with an amorphous component and the annealed films are crystallized and more ordered and the film diffractograms correspond to the cubic structure of In2O3.The refractive index could be modified up to 0.3 in as-deposited films and up to 0.15 in annealed films as functions of the inclination angle of the nanocolumns.Similarly,the band gap energy increases up to about 0.4 eV due to the reduction of the microstrain distribution.It is found that the microstrain distribution,which is related to lattice distortions,defects and the presence of fissures in the films,is the main feature that can be engineered through morphological modifications for achieving the adjustment of the optical properties.

Properties of PET/ITO Thin Films Deposited by DC Magnetron Sputtering

In_2O_3∶SnO_2(ITO) thin films were fabricated on the substrate of flexible polyethylene terephthalate(PET) by DC magnetron sputtering from a ceramic target of In_2O_3/SnO_2(90∶10). Properties of the thin films were characterized by X-ray diffraction(XRD), four-point probe, Hall-effect measurement, UV-Vis spectrophotometer, and scanning electron microscopy(SEM). The effects of sputtering pressure, oxygen partial pressure and deposition temperature on properties of microstructure and optoelectronics properties of PET/ITO thin films were investigated in detail. High-quality ITO thin films on PET substrates with the resistivity as low as 8.5×10-4 Ω·cm and the optical transmittance over 80% in the visible spectrum range were obtained.

Influence of Deposition Temperature on the Structure of Si_3N_4 Thin Film Prepared by MWECR-PECVD

The Si_3N_4 thin film is prepared by MWECR-PECVD at different deposition tem-perature and the structure of the Si_3N_4 thin film is investigated. The results indicate that thestructure of the Si_3N_4 thin film prepared at low deposition temperature is in the amorphousphase. However, when the deposition temperature increases to 280℃, the Si_3N_4 thin film changesto crystalline α-Si_3N_4. With a further increase of the deposition temperature, the grain of theSi_3N_4 thin film becomes more fine, uniform and flat. XRD analysis shows that the structure ofthe Si_3N_4 thin film prepared at 280℃ is of a crystalline structure.

Preparation of ITO transparent conductive film by sol-gel method

The ITO transparent conductive films were prepared on substrate of quartz glass by sol-gel method.The raw materials were nitrate indium,acetylacetone and the dopant of anhydrous chloride(SnCl4).The process from gel to crystalline film and the microstructure of the films were investigated by DTA-TG,XRD and SEM.The influence of preparation processes on the electricity performance of the films was also studied by four-probe apparatus.The results show that the crystallization process of ITO xerogel completes when the heat treatment temperature reaches 600 ℃.The ITO films possesses on vesicular structures accumulated by spherical particles,and both heat treatment temperature and cooling rate have important effects on the resistivity of ITO films.

Tarnish Testing of Copper-Based Alloys Coated with SiO_2-Like Films by PECVD

The tarnishing test in the presence of hydrogen sulfide（H2S） vapors has been used to investigate the tarnish resistance capability of copper-based alloys coated with Si02-like films by means of plasma-enhanced chemical vapor deposition（PECVD） fed with a tetraethoxysilane/oxygen mixture.The chemical and morphological properties of the films have been characterized by using infrared absorption spectroscopy（IR） and scanning electron microscopy（SEM）with energy disperse spectroscopy（EDS）.The corrosion products of the samples after the tarnishing test have been identified by X-ray diffraction analysis（XRD）.It has been found that SiO2-like films formed via PECVD with a high O2 flow rate could protect copper-based alloys from H2S vapor tarnishing.The alloys coated at the O2 flow rate of 20 sccm remain uncorroded after 54days of H2S vapor tarnish testing.The corrosion products for the alloys deposited at a low O2flow rate after 54 days of tarnish testing are mainly composed of brochantite.

Study on adhesion and electro-optical properties of ITO films on flexible PET substrate

High-quality ITO films on flexible PET substrate were prepared by RF magnetron sputtering at low deposition temperature with different Ar gas sputtering pressure.Adhesion and electro-optical properties of ITO films were investigated as a function of Ar partial pressure.The sputtering conditions provide very uniform ITO films with high transparency(>85%in 400-760 nm spectra)and low electrical resistivity(1.408×10^(-3)-1.956×10^(-3)Ω·cm).Scratch test experiments indicate that there is a good adhesion property between ITO films and PET substrate,the critical characteristic load increases from 16.5 to 23.2 N with increasing Ar sputtering pressure from 0.2 to 1.4 Pa.

The Effect of Tin on PECVD-Deposited Germanium Sulfide Thin Films for Resistive RAM Devices

Resistive RAM is a promising, relatively new type of memory with fast switching characteristics. Metal chalcogenide films have been used as the amorphous semiconductor layer in these types of devices. The amount of crystallinity present in the films may be important for both reliable operation and increased longevity of the devices. Germanium sulfide films can be used for these devices, and a possible way to tune the crystalline content of the films is by substituting Sn for some of the Ge atoms in the film. Thin films of GexSnySz containing varying amounts of tin were deposited in a plasma enhanced chemical vapor deposition reactor. Films with 2%, 8%, 15%, 26%, and 34% atomic percentage Sn were deposited to determine crystallinity and structural information with XRD and Raman spectroscopy. Based on these depositions it was determined that at about 8% Sn content and below, the films were largely amorphous, and at about 26% Sn and above, they appeared to be largely crystalline. At 15% Sn composition, which is between 8% and 26%, the film is more a mixture of the two phases. Based on this information, current-voltage (IV) curves of simple memory switching devices were constructed at 5% Sn (in the amorphous region), at 25% Sn (in the crystalline region), and at 15% (in the mixed region). Based on the IV curves from these devices, the 15% composition gave the best overall switching behavior suggesting that a certain degree of order in the semiconductor layer is important for RRAM devices.

Amorphous-Nanocrystalline Transition in Silicon Thin Films Obtained by Argon Diluted Silane PECVD

The Plasma-Enhanced Chemical Vapor Deposition (PECVD) method is widely used compared to other methods to deposit hydrogenated silicon Si:H. In this work, a systematic variation of deposition parameters was done to study the sensitivities and the effects of these parameters on the intrinsic layer material properties. Samples were deposited with 13.56 MHZ PECVD through decomposition of silane diluted with argon. Undoped samples depositions were made in this experiment in order to obtain the transition from the amorphous to nanocrystalline phase materials. The substrate temperature was fixed at 200oC. The influence of depositions parameters on the optical proprieties of the thin films was studied by UV-Vis-NIR spectroscopy. The structural evolution was also studied by Raman spectroscopy and X-ray diffraction (XRD). The structural evolution studies show that beyond 200 W radio frequency power value, we observed an amorphous-nanocrystalline transition, with an increase in crystalline fraction by increasing RF power and working pressure. The deposition rates are found in the range 6 - 10 /s. A correlation between structural and optical properties has been found and discussed.

Surface Morphology Dynamics in ITO Thin Films

In this study, indium tin oxide (ITO) thin films were prepared by electron beam evaporation method on float glass substrates at room temperature (RT). The surface morphology and dynamic scaling behavior of the films were studied by atomic force microscopy (AFM). It was found that average surface roughness values decreased as the film thickness increased from 100 nm to 350 nm. Fractal geometry and statistical physics techniques have been used to study a variety of irregular films within a common framework of the variance thickness. The Hurst exponent H and growth exponent ? for ITO thin films were determined to be 0.73 ? 0.01 and 0.078, respectively. Based on these results, we suggest that the growth of ITO thin films can be described by the combination of the Edwards-Wilkinson equation and Mullins diffusion equation.

Polycrystalline ZnSx Se1—x thin films deposited on ITO glass by MBE

MBE growth of ZnS_xSe_1-x thin films on ITO coated glass substrate s were carried o ut using ZnS and Se sources with the substrate temperature ranging from 270℃ to 330℃. The XRD θ/2θ spectra resulted from these films indicated that the as-gro wn polycrystalline ZnS_xSe_1-x thin films had a preferred orientat ion along the (1 11) planes. The evaluated crystal sizes as deduced from the FWHM of the XRD laye r peaks showed strong growth temperature dependence, with the optimized temperat ure being about 290℃. Both AFM and TEM measurements of these thin films also in dicated a similar growth temperature dependence. High quality ZnS_xSe_1- x thin fil m grown at the optimized temperature had the smoothest surface with lowest RMS v alue of 1.2 nm and TEM cross-sectional micrograph showing a well defined column ar structure.

Deposition of SiOx barrier films by O2/TMDSO RF-PECVD

This paper reports that the SiOx barrier films are deposited on polyethylene terephthalate substrate by plasmaenhanced chemical vapour deposition （PECVD） for the application of transparent barrier packaging. The variations of 02/Tetramethyldisiloxane （TMDSO） ratio and input power in radio frequency （RF） plasma are carried out to optimize barrier properties of the SiOx coated film. The properties of the coatings are characterized by Fourier transform infrared, water vapour transmission rate （WVTR）, oxygen transmission rate （OTR）, and atomic force microscopy analysers. It is found that the 02/TMDSO ratio exceeding 2：1 and the input power over 200 W yield SiOx films with low carbon contents which can be good to the barrier （WVTR and OTR） properties of the SiOx coatings. Also, the film properties not only depend on oxygen concentration of the inlet gas mixtures and input power, but also relate to the surface morphology of the coating.

PEO-Like Functional Films' Polymerization in RF-PECVD

Polymer ethylene oxide （PEO） functional films can be used as a material for biocompatible research. In this paper, we investigated the structures of PEO-like films polymerized on Si surface with diethlyene glycole dimethyl ether （DEGDME） as the precursor and Ar as the dilution gas by plasma enhanced chemical vapor deposition （PECVD）. And the pulse plasma model was employed to polymerize the functional films. The chemical structure of the coatings was investigated by Fourier transform inference （FTIR） and X-ray photoelectron spectroscopy （XPS）. The results indicate that PEO-like structure films can be polymerized by DEGDME/Ar plasma. The concentration of C-O functional groups polymerized in the long plasma-off time was much higher than that in the short plasma-off time. With the same discharge parameters, moreover, the C-O ratio in polymers increased with a higher injected power.

STRUCTURAL PROPERTIES INVESTIGATION ON MICROCRYSTALLINE SILICON FILMS DEPOSITED WITH VHF-PECVD TECHNIQUE

Raman scattering spectroscopy and scanning electron microscopy (SEM) techniques were used to determine the structural properties of two typical series of microc rystalline silicon (μc-Si:H) films deposited at different VHF plasma power and different working gas pressure by very high frequency plasma enhanced chemical v apor deposition (VHF-PECVD) technique. Raman spectra measurements show that both crystalline volume fraction Xc and average grain size d of μc-Si : H films ar e strongly affected by the two deposition conditions and are more sensitive to w orking gas pressure than VHF plasma power. SEM characterizations have further co nfirmed that VHF plasma power and working gas pressure could clearly enhance the surface roughness of μc-Si : H films ascribing to polymerization reactions, w hich is also more sensitive to working gas pressure than VHF plasma power.