Microstructure and properties of indium tin oxide thin films deposited by RF-magnetron sputtering

Tin-doped indium oxide (ITO) thin films were prepared using conventional radio frequency (RF) planar magne-tron sputtering equipped with IR irradiation using a ceramic target of In2O3/SnO2 with a mass ratio of 1:1 at various IR irradiation temperatures TI (from room temperature to 400°C). The refractive index, deposited ratio, and resistivity are functions of the sputtering Ar gas pressure. The microstructure of ITO thin films is related to IR TI, the crystalline seeds appear at TI = 300°C, and the films are amorphous at the temperature ranging from 27°C to 400°C. AFM investigation shows that the roughness value of peak-valley of ITO thin film (Rp-v) and the surface microstructure of ITO thin films have a close relation with TI. The IR irradiation results in a widening value of band-gap energy due to Burstein-Moss effect and the maximum visible transmittance shifts toward a shorter wavelength along with a decrease in the film’s refractive index. The plasma wavelength and the refractive index of ITO thin films are relative to the TI. XPS investigation shows that the photoelectrolytic properties can be deteriorated by the sub-oxides. The deterioration can be decreased by increasing the oxygen flow rate (fo2), and the mole ratio of Sn/In in the samples reduces with an increase in fo2.

Preparation and Characterization of Nano-Particles PZT Ferroelectric Thin Films by RF-Magnetron Sputtering

Pt/Ti 底部电极被 magnetrondual-facing-target 劈啪作响系统在 SiO_2/Si 底层上制作。铅锆酸盐泰坦吃了(PZT ) 薄电影是由无线电的扔的 onPt/Ti/ SiO_2/Si 底层频率(RF ) 磁控管劈啪作响系统。为 5 h 被扔的 PZTthin 电影的厚度是大约 800 nm。PZT 薄电影在 700 deg C 为 20 min 在 Ar 环境和 rapid-thermal-annealed 扔了的 XRD 系列表演有好结晶化行为和 perovskite 结构。雏晶的吝啬的直径是 70 nm 和表面的 AFM 显微图表演 PZT 薄电影组织一致、稠密。未加工的平均数，根平均数平方粗糙和 PZT 薄电影的吝啬的粗糙是 34.357 nm， 2.479 nm 并且 1.954 nmrespectively。因为测试频率是 1 kHz， PZT 薄电影经常的电介质是 327.6。Electrichysteresis 循环显示出那强制的地力量，剩余极化力量和 PZT 薄电影的自发的极化力量分别地是 50 kV/cm， 10 muC/cm^2 和 13 muC/cm^2。

Microstructure and properties of indium tin oxide thin films deposited by RF-magnetron sputtering

Tin-doped indium oxide （ITO） thin films were prepared using conventional radio frequency （RF） planar magnetron sputtering equipped with IR irradiation using a ceramic target of In2O3/SnO2 with a mass ratio of 1∶1 at various IR irradiation temperatures T1 （from room temperature to 400?℃）. The refractive index,deposited ratio,and resistivity are functions of the sputtering Ar gas pressure. The microstructure of ITO thin films is related to IR T1,the crystalline seeds appear at T1=300?℃,and the films are amorphous at the temperature ranging from 27?℃ to 400?℃. AFM investigation shows that the roughness value of peak-valley of ITO thin film （R p-v ） and the surface microstructure of ITO thin films have a close relation with T1. The IR irradiation results in a widening value of band-gap energy due to Burstein-Moss effect and the maximum visible transmittance shifts toward a shorter wavelength along with a decrease in the film’s refractive index. The plasma wavelength and the refractive index of ITO thin films are relative to the T1. XPS investigation shows that the photoelectrolytic properties can be deteriorated by the sub-oxides. The deterioration can be decreased by increasing the oxygen flow rate （fo2）,and the mole ratio of Sn/In in the samples reduces with an increase in fo2.

Effect of grain size on ferroelectric and dielectric properties of Bi_(3.25)La_(0.75)Ti_(3)O_(12) thin films prepared by rf-magnetron sputtering

Bi_(3.25)La_(0.75)Ti_(3)O_(12)(BLT)thin films are promising materials used in non-volatile memories.In this work,BLT films were deposited on Pt(111)/Ti/SiO_(2)/Si substrates by rf-magnetron sputtering method followed by annealing treatments.The microstructures of BLT thin films were investigated via X-ray diffraction(XRD),scanning electron microscopy(SEM)and atomic force microscopy(AFM).With the increase in annealing temperature,the grain size increased significantly and the preferred crystalline orientation changed.A well-saturated hysteresis loop with a superior remnant polarization of 15.4μC/cm^(2) was obtained for BLT thin films annealed at 700°C.The results show that the dielectric constant decreased with the increase in grain sizes.

Surface Metallization of Glass Fiber(GF)/Polyetheretherketone(PEEK) Composite with Cu Coatings Deposited by Magnetron Sputtering and Electroplating

Surface metallization of glass fiber(GF)/polyetheretherketone(PEEK)[GF/PEEK] is conducted by coating copper using electroplating and magnetron sputtering and the properties are determined by X-ray diffraction(XRD), scanning electron microscopy(SEM), and electron backscatter diffraction(EBSD).The coating bonding strength is assessed by pull-out tests and scribing in accordance with GB/T 9286-1998.The results show that the Cu coating with a thickness of 30 μm deposited on GF/PEEK by magnetron sputtering has lower roughness, finer grain size, higher crystallinity, as well as better macroscopic compressive stress,bonding strength, and electrical conductivity than the Cu coating deposited by electroplating.

Structural and magnetic properties of micropolycrystalline cobalt thin films fabricated by direct current magnetron sputtering

Pure cobalt(Co)thin films were fabricated by direct current magnetron sputtering,and the effects of sputtering power and pres-sure on the microstructure and electromagnetic properties of the films were investigated.As the sputtering power increases from 15 to 60 W,the Co thin films transition from an amorphous to a polycrystalline state,accompanied by an increase in the intercrystal pore width.Simultaneously,the resistivity decreases from 276 to 99μΩ·cm,coercivity increases from 162 to 293 Oe,and in-plane magnetic aniso-tropy disappears.As the sputtering pressure decreases from 1.6 to 0.2 Pa,grain size significantly increases,resistivity significantly de-creases,and the coercivity significantly increases(from 67 to 280 Oe),which can be attributed to the increase in defect width.Corres-pondingly,a quantitative model for the coercivity of Co thin films was formulated.The polycrystalline films sputtered under pressures of 0.2 and 0.4 Pa exhibit significant in-plane magnetic anisotropy,which is primarily attributable to increased microstress.

Facile integration of an Al-rich Al_(1-x)In_(x)N photodetector on free-standing GaN by radio-frequency magnetron sputtering

Al_(1-x)In_(x)N, a Ⅲ-nitride semiconductor material, is currently of great research interest due to its remarkable physical properties and chemical stability. When the Al and In compositions are tuned, its band-gap energy varies from 0.7 eV to 6.2 eV, which shows great potential for application in photodetectors. Here, we report the fabrication and performance evaluation of integrated Al_(1-x)In_(x)N on a free-standing GaN substrate through direct radio-frequency magnetron sputtering.The optical properties of Al_(1-x)In_(x)N will be enhanced by the polarization effect of a heterostructure composed of Al_(1-x)In_(x)N and other Ⅲ-nitride materials. An Al_(1-x)In_(x)N/Ga N visible-light photodetector was prepared by semiconductor fabrication technologies such as lithography and metal deposition. The highest photoresponsivity achieved was 1.52 A·W^(-1)under 365 nm wavelength illumination and the photodetector was determined to have the composition Al0.75In0.25N/GaN.A rise time of 0.55 s was observed after transient analysis of the device. The prepared Al_(1-x)In_(x)N visible-light photodetector had a low dark current, high photoresponsivity and fast response speed. By promoting a low-cost, simple fabrication method,this study expands the application of ternary alloy Al_(1-x)In_(x)N visible-light photodetectors in optical communication.

High Permeability in Broadband of Co-sputtered [Fe-Fe_(20)Ni_(80)/Cr]_(n) Multilayer Films

To achieve high microwave permeability in wide-band for the micron-thick magnetic films,[Fe-Fe_(20)Ni_(80)/Cr]_(n) multilayer structure was proposed by co-sputtering Fe and FeNi to form the magnetic layers and Cr to form the interlayers.The multilayer structure contributes to the high permeability by reducing the coercivity and diminishing out-of-plane magnetization.The maximum imaginary permeability of[Fe-Fe_(20)Ni_(80)/Cr]_(n) multilayer film reaches a large value of 800 at 0.52 GHz even though its overall thickness exceeds 1μm.Besides,the magnetic resonance frequency of the multilayer film can be modulated from 0.52 to 1.35 GHz by adjusting the sputtering power of Fe from 0 to 86 W,and its bandwidth for μ’’>200(Δf) is as large as 2.0 GHz.The desirable broad Δf of magnetic permeability,which can be well fitted by the Landau-Lifshitz-Gilbert equations,is due to dual magnetic resonances originated from double magnetic phases of Fe and FeNi that are of different saturation magnetization.The micron-thick multilayer films with high permeability in extended waveband are promising candidate for electromagnetic noise suppression application.

Synthesis and properties of Cr-Al-Si-N films deposited by hybrid coating system with high power impulse magnetron sputtering (HIPIMS) and DC pulse sputtering

The CrN and Cr-Al-Si-N films were deposited on Si wafer and SUS 304 substrates by a hybrid coating system with high power impulse magnetron sputtering (HIPIMS) and a DC pulse sputtering using Cr and AlSi targets under N2/Ar atmosphere.By varying the sputtering current of the AlSi target in the range of 0-2.5 A,both the Al and Si contents in the films increased gradually from 0 to 19.1% and 11.1% (mole fraction),respectively.The influences of the AlSi cathode DC pulse current on the microstructure,phase constituents,mechanical properties,and oxidation behaviors of the Cr-Al-Si-N films were investigated systematically.The results indicate that the as-deposited Cr-Al-Si-N films possess the typical nanocomposite structure,namely the face centered cubic (Cr,Al)N nano-crystallites are embedded in the amorphous Si3N4 matrix.With increasing the Al and Si contents,the hardness of the film first increases from 20.8 GPa for the CrN film to the peak value of 29.4 GPa for the Cr0.23Al0.14Si0.07 N film,and then decreases gradually.In the meanwhile,the Cr0.23Al0.14Si0.07N film also possesses excellent high-temperature oxidation resistance that is much better than that of the CrN film at 900 or 1000 °C.

Influence of temperature on the microstructure of V_2O_5 film prepared by DC magnetron sputtering

V2O5 films were prepared on silicon wafers by DC magnetron sputtering and post-annealing under various conditions. The influence of depositing and post-annealing temperatures on microstructure of V2O5 films was studied by XRD and Raman scattering measurements. The results reveal that sputtered V2O5 films show preferred growth orientation along (001) planes and the c-axis is perpendicular to the silicon substrate surface. It is interesting to find that both the V2O5 film deposited at temperature of 511 ℃ and the one annealed at 500 ℃ exhibit desirable layer-type structure of orthorhombic symmetry. Such layer-typed V2O5 films are promising candidates for cathodes of rechargeable lithium or magnesium thin-film batteries.

Preparation and characteristics of indium tin oxide (ITO) thin films at low temperature by r.f. magnetron sputtering

Low resistivity and highly transparent ITO conducting films for solar cell applications were fabricated at low temperature by r.f. magnetron sputtering. ITO films were deposited on glass and silicon substrate. Electrical, optical, structural and morphological properties of the ITO films were investigated in terms of the preparation conditions. The annealing treatment has improved the properties of the ITO films at different degree. The maximum transmittance of the obtained ITO films in the visible range is over 92%, and the low resistivity for the ITO films are about 3.85×10-4 Ω·cm at 80 ℃, 80 W after annealing.

EFFECT OF Ar PRESSURE ON STRUCTURAL AND ELECTRICAL PROPERTIES OF Cu FILMS DEPOSITED ON GLASS BY DC MAGNETRON SPUTTERING

Cu films with thickness of 630-1300nm were deposited on glass substrates withoutheating by DC magnetron sputtering in pure Ar gas. Ar pressure was controlled to0.5, 1.0 and 1.5Pa respectively. The target voltage was fixed at 500V but the targetcurrent increased from 200 to 1150mA with Ar pressure increasing. X-ray diffrac-tion, scanning electron microscopy and atomic force microscopy were used to observethe structural characterization of the films. The resistivity of the films was measuredusing four-point probe technique. At all the Ar pressures, the Cu films have mixturecrystalline orientations of [111], [200] and [220] in the direction of the film growth.The film deposited at lower pressure shows more [111] orientation while that depositedat higher pressure has more [220] orientation. The amount of larger grains in the filmprepared at 0.5Pa Ar pressure is slightly less than that prepared at 1. 0Pa and 1.5PaAr pressures. The resistivities of the films prepared at three different Ar pressures rep-resent few differences, about 3-4 times of that of bulk material. Besides the depositionrate increases with Ar pressure because of the increase in target current. The contri-bution of the bombardment of energetic reflected Argon atoms to these phenomena isdiscussed.

STUDY ON Ni-Cr SYSTEM SOLAR SELECTIVE THIN FILMS PREPARED BY MAGNETRON REACTIVE SPUTTERING PROCESS

Ni-Cr System solar selective thin solid films were prepared by d.c. magnetron reactive sputtering under the atmosphere of O2 and N2. Ni-Cr alloy was chosen as target material and copper sheets as substrate. Using SEAL Spectrophotometer and Talystep to analyze the relations between the selective characteristic and the structure, the formation and the thickness of the thin films. The aim is to obtain good solar selective thin films with high absorptance and low emittance, which is applied to flat plate solar heat collectors.

A comparison of transmittance properties between ZnO∶Al films for transparent conductors for solar cells deposited by sputtering of AZO and cosputtering of AZO/ZnO

Aluminum-doped zinc oxide (AZO) thin films were deposited on sapphire (002) and glass substrates by two different sputtering techniques radio frequency magnetron cosputtering of AZO and ZnO targets and sputtering of an AZO target. The dependence of the photoluminescence (PL) and transmittance properties of the AZO films deposited by cosputtering and sputtering on the AZO/ZnO target power ratio, R and the O2/Ar flow ratio, r were investigated, respectively. Only a deep level emission peak appears in the PL spectra of cosputtered AZO films whereas both UV emission and deep level emission peaks are observed in the PL spectra of sputtered AZO films. The absorption edges in the transmittance spectra of the AZO films shift to the lower wavelength region as R and r increase. Effects of crystallinity, surface roughness, PL on the transmittance of the AZO films were also explained using the X-ray diffraction (XRD), atomic force microscopy (AFM), and PL analysis results.

Effects of sputtering power and annealing temperature on surface roughness of gold films for high-reflectivity synchrotron radiation mirrors

Gold films deposited by direct current magnetron sputtering are used for synchrotron radiation optics. In this study, the microstructure and surface roughness of gold films were investigated for the purpose of developing high-reflectivity mirrors. The deposition process was first optimized. Films were fabricated at different sputtering powers (15, 40, 80, and 120 W) and characterized using grazing incidence X-ray reflectometry, X-ray diffraction, and atomic force microscopy. The results showed that all the films were highly textured, having a dominant Au (111) orientation, and the film deposited at 80 W had the lowest surface roughness. Subsequently, post-deposition annealing from 100 to 200℃ in a vacuum was performed on the films deposited at 80 W to investigate the effect of annealing on the microstructure and surface roughness of the films. The grain size, surface roughness, and their relationship were investigated as a function of annealing temperature. AFM and XRD results revealed that at annealing temperatures of 175 ℃ and below, microstructural change of the films was mainly manifested by the elimination of voids. At annealing temperatures higher than 175℃, grain coalescence occurred in addition to the void elimination, causing the surface roughness to increase.

Influence of boron contents on properties of AlMgB films prepared by RF magnetron sputtering

Ternary AlMgB thin films were synthesized on silicon (100) substrate at 573 K by radio frequency (RF) magnetron sputtering method using one Al/Mg co-target and one boron target. The thickness of the as-deposited thin film was controlled to 500 nm by adjusting deposition time. The influences of sputtering powers on the elemental contents and structural and mechanical properties were investigated by electron probe microanalysis (EPMA), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), and nanoindentation system. At the same time, the ball-on-disk tribometer was used to measure the friction behavior of the films. Experimental results indicate that the as-deposited boron-rich films are primarily amorphous structure and possess a dramatic high hardness up to 39 GPa with 99.03 at.% boron. Obviously, it has exceeded the hardness value of 32 GPa of pure AlMgB 14 bulk material prepared by sintering method. Furthermore, the friction coefficients of the thin films exhibit an average value as low as 0.3, which is considered as the effect of self-lubricating.

High Potential Columnar Nanocrystalline AlN Films Deposited by RF Reactive Magnetron Sputtering

Columnar nanocrystalline aluminum nitride(cnc-AlN) thin films with(002) orientation and uniform texture have been deposited successfully on large silicon wafers by RF reactive magnetron sputtering.At the optimum sputtering parameters, the deposited cnc-AlN thin films show a c-axis preferred orientation with a crystallite size of about 28 nm and surface roughness(RMS) of about 1.29 nm. The cnc-AlN thin films were well transparent with an optical band gap about 4.8 e V, and the residual compressive stress and the defect density in the film have been revealed by Ramon spectroscopy. Moreover, piezoelectric performances of the cnc-AlN thin films executed effectively in a film bulk acoustic resonator structure.

Fabrication and its characteristics of hard coating Ti-Al-N system prepared by DC magnetron sputtering

Pseudobinary Ti 1 x Al x N films were synthesized on Si (100) wafer by DC magnetron sputtering method using Ti 1 x Al x alloy targets with different Al contents. The composition of the Ti 1 x Al x N films was determined by electron probe microanalysis (EPMA). Structural characteristic was performed by X-ray diffraction (XRD), transmission electron microscopy (TEM), and high-resolution TEM (HRTEM). First principles virtual crystal calculations for the Ti 1 x Al x N disordered alloys were used for the XRD simulations. The crystalline structure of the Ti 0.61 Al 0.39 N film was found to be a metastable single phase with NaCl (B1) structure. Its lattice constant, determined by XRD, was less than that of pure TiN. With the increase of Al content, the lattice constant of B1 phase was continually decreased, while würtzite (B4) structure was observed in the Ti 0.40 Al 0.60 N film. When x reached 0.75, the B1 phase disappeared, and only B4 phase was remained. The critical Al content for the phase transition from NaCl to würtzite structure in this paper was about 0.60, which could be explained by both the thermodynamic model and the electron theory. As-deposited Ti 1 x Al x N films exhibited excellent mechanical properties. Hardness measurements of Ti 1 x Al x N films showed a high value of 45GPa for x=0.39 and was decreased to value of 27 GPa with increasing Al at x=0.60.

Effects of substrate temperature and deposition time on the morphology and corrosion resistance of FeCoCrNiMo0.3 high-entropy alloy coating fabricated by magnetron sputtering

The effects of substrate temperature and deposition time on the morphology and corrosion resistance of FeCoCrNiMo0.3 coating fabricated by magnetron sputtering were investigated by scanning electron microscopy and electrochemical tests.The FeCoCrNiMo0.3 coating was mainly composed of the face-centered cubic phase.High substrate temperature promoted the densification of the coating,and the pitting resistance and protective ability of the coating in 3.5wt%NaCl solution was thus improved.When the deposition time was prolonged at 500℃,the thickness of the coating remarkably increased.Meanwhile,the pitting resistance improved as the deposition time increased from 1 to 3 h;however,further improvement could not be obtained for the coating sputtered for 5 h.Overall,the pitting resistance of the FeCoCrNiMo0.3 coating sputtered at 500℃for 3 h exceeds those of most of the reported high-entropy alloy coatings.

Sputtering of W Mo alloy under ion bombardment

The distribution of plasma density in the vicinity of the W Mo alloy source in the process of double glow discharge plasma surface alloying was diagnosed using the moveable Langmuir probe. The sputtering law, surface composition and morphological variation of the W Mo alloy source was studied. The experimental results show that there exists obvious preferential sputtering on the surface of the W Mo alloy source under the argon ion bombardment; the stable period is reached after a transitional period, and the preferential sputtering occurs in a definite range of composition(mole fraction): 70%～75% Mo, 22%～25% W; there appears segregation on the surface of the W Mo alloy source.