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...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.展开更多
The CuO_x thin film photocathodes were deposited on F-doped Sn O_2 (FTO)transparent conducting glasses by alternating current(AC)magnetron reactive sputtering under different Ar:O_2 ratios.The advantage of this deposi...The CuO_x thin film photocathodes were deposited on F-doped Sn O_2 (FTO)transparent conducting glasses by alternating current(AC)magnetron reactive sputtering under different Ar:O_2 ratios.The advantage of this deposited method is that it can deposit a CuO_x thin film uniformly and rapidly with large scale.From the photoelectrochemical(PEC)properties of these CuO_x photocathodes,it can be found that the CuO_x photocathode with Ar/O_2 30:7 provide a photocurrent density ofà3.2 m A cm^(à2)under a bias potentialà0.5 V(vs.Ag/Ag Cl),which was found to be twice higher than that of Ar/O_2 with 30:5.A detailed characterization on the structure,morphology and electrochemical properties of these CuO_x thin film photocathodes was carried out,and it is found that the improved PEC performance of CuO_x semiconductor photocathode with Ar/O_230:7 attributed to the less defects in it,indicating that this Ar/O_230:7 is an optimized condition for excellent CuO_x semiconductor photocathode fabrication.展开更多
Nitrogen doping of silver oxide(AgxO) film is necessary for its application in transparent conductive film and diodes because intrinsic AgxO film is a p-type semiconductor with poor conductivity.In this work,a series ...Nitrogen doping of silver oxide(AgxO) film is necessary for its application in transparent conductive film and diodes because intrinsic AgxO film is a p-type semiconductor with poor conductivity.In this work,a series of AgxO films is deposited on glass substrates by direct-current magnetron reactive sputtering at different flow ratios(FRs) of nitrogen to O2.Evolutions of the structure,the reflectivity,and the transmissivity of the film are studied by X-ray diffractometry and sphectrophotometry,respectively.The specular transmissivity and the specular reflectivity of the film decreasing with FR increasing can be attributed to the evolution of the phase structure of the film.The nitrogen does not play the role of an acceptor dopant in the film deposition.展开更多
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), sc...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.展开更多
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...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.展开更多
Single(200)-oriented TiN thin films were deposited on quartz substrate by direct current(DC) magnetron reactive sputtering process at a wide range of substrate temperature from 200 to 600 ℃.The effects of sputtering ...Single(200)-oriented TiN thin films were deposited on quartz substrate by direct current(DC) magnetron reactive sputtering process at a wide range of substrate temperature from 200 to 600 ℃.The effects of sputtering pressure and substrate temperature on the crystalline nature,morphology,electrical and optical properties of the deposited thin films were analyzed by X-ray diffraction(XRD),atomic force microscopy(AFM),four-point resistivity test system and ultraviolet visible near-infrared(UV-Vis-NIR) spectroscopy,respectively.The results show that single(200)-oriented TiN thin films can be obtained at a wide range of substrate temperature from 200 to 600 ℃ with the grain size increasing from 35.9 to 64.5 nm.The resistivity of the product is as low as95 μΩ·cm,and the value of the optical reflectance is above68 % in the near-infrared(NIR) range of 760-1500 nm.展开更多
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 e...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.展开更多
TiO2 thin film has attracted considerable attention in recent years, due to its different refractive index and transparency with amorphous and different crysta ls in the visible and near-infrared wavelength region, hi...TiO2 thin film has attracted considerable attention in recent years, due to its different refractive index and transparency with amorphous and different crysta ls in the visible and near-infrared wavelength region, high dielectric constant, wide band gap, high wear resistance and stability, etc, for which make it being used in many fields. This paper aims to investigate the optical characterizatio n of thin film TiO2 on silicon wafer. The TiO2 thin films were prepared by DC re active magnetron sputtering process from Ti target. The reflectivity of the film s was measured by UV-3101PC, and the index of refraction (n) and extinction coef ficient (k) were measured by n & k Analyzer 1200.展开更多
Carbon nitride thin films were deposited on Si(001) using unbalanced magnetron sputtering at different experimental parameters. The effects of nitrogen partial pressure, substrate temperature and substrate bias on the...Carbon nitride thin films were deposited on Si(001) using unbalanced magnetron sputtering at different experimental parameters. The effects of nitrogen partial pressure, substrate temperature and substrate bias on the deposition rate and nitrogen content are discussed.展开更多
To explore the relationship between the chemical bonding and mechanical properties for germanium carbide (Ge1-xCx) films,the Ge1-xCx films are prepared via reactive magnetron sputtering in a mixture of CH4/Ar discharg...To explore the relationship between the chemical bonding and mechanical properties for germanium carbide (Ge1-xCx) films,the Ge1-xCx films are prepared via reactive magnetron sputtering in a mixture of CH4/Ar discharge,and their composition,chemical bonding and hardness were investigated as a function of substrate temperature (Ts). The results show that Ts remarkably influences the chemical bonding of Ge1-xCx film,which results in a pronounced change in the film hardness. As Ts increases from ambient (60 ℃) to 500 ℃,the Ge content in the film gradually increases,which promotes forming sp3 C-Ge bonds in the film at the expense of sp2C-C bonds. Furthermore,it is found that with increasing Ts the fraction of C-H bonds in Ge1-xCx film gradually decreases,which is attributed to an enhancement in the desorption rate of C-Hn(n=1,2,3) species decomposed from methane. The transition from graphite-like sp2 C-C to diamond-like sp3C-Ge bonds as well as the reduction in C-H bonds in the film with increasing Ts promotes forming the compact three-dimensional network structure,which significantly enhances the hardness of the film from 5.8 to 10.1 GPa.展开更多
The TiN coatings on the surfaces of various cemented carbides were performed by use of reactive magnetron sputtering.Thehighest microhardness which was obtained in our experiment was 49 GPa.The order of effect weights...The TiN coatings on the surfaces of various cemented carbides were performed by use of reactive magnetron sputtering.Thehighest microhardness which was obtained in our experiment was 49 GPa.The order of effect weights of deposition parameters isP_∑,β,Ts,...,which resulted from the LI6 experiments according to orthogonal design.The pole density analysis indicated thatthere were a few of the textureless samples.The crystal orientation of TiN exhibited clear regularity and affected microhardnessand other properties of films remarkably.A concept relating to structure factor was proposed.A layer-like structure was found.SAES showed that a transition layer exists between substrate and coating and its thickness is of the order of micron.The forma-tion mechanism of film was discussed.展开更多
In order to make sufficient use of reactive cylindrical magnetron plasma for depositing compound thin films, it is necessary to characterize the hysteresis behavior of the discharge. Cylindrical magnetron plasmas with...In order to make sufficient use of reactive cylindrical magnetron plasma for depositing compound thin films, it is necessary to characterize the hysteresis behavior of the discharge. Cylindrical magnetron plasmas with different targets namely titanium and aluminium are studied in an argon/oxygen and an argon/nitrogen gas environment respectively. The aluminium and titanium emission lines are observed at different flows of reactive gases. The emission intensity is found to decrease with the increase of the reactive gas flow rate. The hysteresis behavior of reactive cylindrical magnetron plasma is studied by determining the variation of discharge voltage with increasing and then reducing the flow rate of reactive gas,while keeping the discharge current constant at 100 m A. Distinct hysteresis is found to be formed for the aluminium target and reactive gas oxygen. For aluminium/nitrogen, titanium/oxygen and titanium/nitrogen, there is also an indication of the formation of hysteresis; however, the characteristics of variation from metallic to reactive mode are different in different cases. The hysteresis behaviors are different for aluminium and titanium targets with the oxygen and nitrogen reactive gases, signifying the difference in reactivity between them. The effects of the argon flow rate and magnetic field on the hysteresis are studied and explained.展开更多
Biodegradable magnesium alloys are promising candidates for temporary fracture fixation devices in orthopedics;nevertheless,its fast degradation rate at the initial stage after implantation remains as one of the main ...Biodegradable magnesium alloys are promising candidates for temporary fracture fixation devices in orthopedics;nevertheless,its fast degradation rate at the initial stage after implantation remains as one of the main challenges to be resolved.ZrO_(2)-based coatings to reduce the degradation rate of the Mg-implants are an attractive solution since they show high biocompatibility and stability.In this work,the degradation,cytotoxicity,and antibacterial performance of ZrO_(2)thin films deposited by magnetron sputtering on a Mg-Zn-Ca alloy was evaluated.Short-term degradation of ZrO_(2)-coated and uncoated samples was assessed considering electrochemical techniques and H_(2)evolution(gas chromatography).Additionally,long term degradation was assessed by mass-loss measurements.The results showed that a 380 nm ZrO_(2)coating reduces the degradation rate and H_(2)evolution of the alloy during the initial 3 days after immersion but allows the degradation of the bare alloy for the long-term.The ZrO_(2)coating does not compromise the biocompatibility of the alloy and permits better cell adhesion and proliferation of mesenchymal stem cells directly on its surface,in comparison to the bare alloy.Finally,the ZrO_(2)coating prevents the adhesion and biofilm formation of S.aureus.展开更多
Using a radio-frequency reactive magnetron sputtering technique,a series of the single-phased Ag2O films are deposited in a mixture of oxygen and argon gas with a flow ratio of 2:3 by changing substrate temperature(T ...Using a radio-frequency reactive magnetron sputtering technique,a series of the single-phased Ag2O films are deposited in a mixture of oxygen and argon gas with a flow ratio of 2:3 by changing substrate temperature(T s).Effects of the T s on the microstructure and optical properties of the films are investigated by using X-ray diffractometry,scanning electron microscopy and spectrophotometry.The single-phased Ag2O films deposited at values of T s below 200℃ are(111) preferentially oriented,which may be due to the smallest free energy of the(111) crystalline face.The film crystallization becomes poor as the value of T s increases from 100℃ to 225℃.In particular,the Ag2O film deposited at T s = 225℃ loses the 111 preferential orientation.Correspondingly,the film surface morphology obviously evolves from a uniform and compact surface structure to a loose and gullied surface structure.With the increase of T s value,the transmissivity and the reflectivity of the films in the transparent region are gradually reduced,while the absorptivity gradually increases,which may be attributed to an evolution of the crystalline structure and the surface morphology of the films.展开更多
This paper reports that a series of silver oxide (Ag x O) films are deposited on glass substrates by direct-current reactive magnetron sputtering at a substrate temperature of 250 C and an oxygen flux ratio of 15:18 b...This paper reports that a series of silver oxide (Ag x O) films are deposited on glass substrates by direct-current reactive magnetron sputtering at a substrate temperature of 250 C and an oxygen flux ratio of 15:18 by modifying the sputtering power (SP).The Ag x O films deposited apparently show a structural evolution from cubic biphased (AgO + Ag 2 O) to cubic single-phased (Ag 2 O),and to biphased (Ag 2 O + AgO) structure.Notably,the cubic single-phased Ag 2 O film is deposited at the SP=105 W and an AgO phase with 220 orientation discerned in the Ag x O films deposited using the SP > 105 W.The transmissivity and reflectivity of the Ag x O films in transparent region decrease with the increase the SP,whereas the absorptivity inversely increases with the increase of the SP.These results may be due to the structural evolution and the increasing film thickness.A redshift of the films' absorption edges determined in terms of Tauc formula clearly occurs from 3.1 eV to 2.73 eV with the increase of the SP.展开更多
TiZrN films were deposited on unheated Si (100) substrates by reactive dc magnetron co-sputtering. Titanium and zirconium metals were used as sputtering targets. Ar and N2 gas were used as sputtering gas and reactive ...TiZrN films were deposited on unheated Si (100) substrates by reactive dc magnetron co-sputtering. Titanium and zirconium metals were used as sputtering targets. Ar and N2 gas were used as sputtering gas and reactive gas, with the flow rates of 8 and 4 sccm, respectively. The Zr sputtering current was fixed at 0.6 A and Ti sputtering current varied from 0.6 to 1.2 A. The deposition time for all the deposited films was 60 min. The effects of Ti sputtering current on the structure and morphology of the films were investigated by X-ray diffraction (XRD), atomic force microscopy (AFM), field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). It was found that all the prepared films were (Ti,Zr)N solid solution. Furthermore, the lattice parameter was found to decrease whereas the crystallite size, RMS roughness and film thickness increased with increasing Ti sputtering current. As a result, the crystallinity of the films increased what is in agreement with XRD results.展开更多
Cu3N and AlxCu3N films were prepared with reactive magnetron sputtering method. The two films were deposited on glass substrates at 0.8 Pa N2 partial pressure and 100 ℃ substrate temperature by using a pure Cu and Al...Cu3N and AlxCu3N films were prepared with reactive magnetron sputtering method. The two films were deposited on glass substrates at 0.8 Pa N2 partial pressure and 100 ℃ substrate temperature by using a pure Cu and Al target,respectively. X-ray diffraction (XRD) measurements show that the un-doped film was composed of Cu3N crystallites with anti-ReO3 structure and adopted 111 preferred orientation. XRD shows that t he growth of Al-doped copper nitride films (AlxCu3N) was affected strongly by doping Al,the intensity of 111 peak decreases with increasing the concentration of Al and the high concentration of Al could prevent the Cu3N f rom crystallization. AFM shows that the surface of AlxCu3N film is smoother than that of Cu3N film. Compared w ith the Cu3N films,the resistivities of the Al-doped copper nitride films (AlxCu3N) have been reduced,and the microhardness has been enhanced.展开更多
ZrO2 thin films were deposited by r.f. reactive unbalanced magnetron sputtering. The influence of electromagnetic coil current on microstructure and optical properties of the films was investigated. At low coil curren...ZrO2 thin films were deposited by r.f. reactive unbalanced magnetron sputtering. The influence of electromagnetic coil current on microstructure and optical properties of the films was investigated. At low coil current of 0.2A, small grains are produced. With the increase of coil current, the deposition rate and surface roughness are decreased and the packing density in proportion to the refractive index is increased remarkably. The refractive index is as high as 2.236 (at X=600nm) at 0.4A. At the high coil current of 0.6A, grains appear to grow up due to thermal effects and therefore optical properties of the films are deteriorated a little.展开更多
基金supported by the Chinese Academy of Sciences within“The Hundred Talent Project"by the Bureau for Sciences and Technology of Guangzhou City within the"Nanoproject"
文摘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.
基金financially supported by the National Natural Science Foundation of China (Grant Nos. 41506093)
文摘The CuO_x thin film photocathodes were deposited on F-doped Sn O_2 (FTO)transparent conducting glasses by alternating current(AC)magnetron reactive sputtering under different Ar:O_2 ratios.The advantage of this deposited method is that it can deposit a CuO_x thin film uniformly and rapidly with large scale.From the photoelectrochemical(PEC)properties of these CuO_x photocathodes,it can be found that the CuO_x photocathode with Ar/O_2 30:7 provide a photocurrent density ofà3.2 m A cm^(à2)under a bias potentialà0.5 V(vs.Ag/Ag Cl),which was found to be twice higher than that of Ar/O_2 with 30:5.A detailed characterization on the structure,morphology and electrochemical properties of these CuO_x thin film photocathodes was carried out,and it is found that the improved PEC performance of CuO_x semiconductor photocathode with Ar/O_230:7 attributed to the less defects in it,indicating that this Ar/O_230:7 is an optimized condition for excellent CuO_x semiconductor photocathode fabrication.
基金Project supported by the National Natural Science Foundation of China (Grant No. 60807001)the Foundation of Henan Educational Committee,China (Grant No. 2010A140017)the College Young Teachers Program of Henan Province and the Graduate Innovation Fund of Zhengzhou University (Grant No. 11L10102)
文摘Nitrogen doping of silver oxide(AgxO) film is necessary for its application in transparent conductive film and diodes because intrinsic AgxO film is a p-type semiconductor with poor conductivity.In this work,a series of AgxO films is deposited on glass substrates by direct-current magnetron reactive sputtering at different flow ratios(FRs) of nitrogen to O2.Evolutions of the structure,the reflectivity,and the transmissivity of the film are studied by X-ray diffractometry and sphectrophotometry,respectively.The specular transmissivity and the specular reflectivity of the film decreasing with FR increasing can be attributed to the evolution of the phase structure of the film.The nitrogen does not play the role of an acceptor dopant in the film deposition.
基金Funded by Shenzhen-Hong Kong Innovative Collaborative Research and Development Program (Nos.SGLH20181109 110802117, CityU 9240014)Innovation Project of Southwestern Institute of Physics (Nos.202001XWCXYD002, 202301XWCX003)CNNC Young Talent Program (No.2023JZYF-01)。
文摘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.
基金the financial support from the National Key Research and Development Program of China(No.2017YFB0305500)the State Key Laboratory of Powder Metallurgy,Central South University,Changsha,China.
文摘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.
基金the National Natural Science Foundation of China and External science and technology cooperation program of Jiangxi Province(Nos.11364032 and 20151BDH80030)。
文摘Single(200)-oriented TiN thin films were deposited on quartz substrate by direct current(DC) magnetron reactive sputtering process at a wide range of substrate temperature from 200 to 600 ℃.The effects of sputtering pressure and substrate temperature on the crystalline nature,morphology,electrical and optical properties of the deposited thin films were analyzed by X-ray diffraction(XRD),atomic force microscopy(AFM),four-point resistivity test system and ultraviolet visible near-infrared(UV-Vis-NIR) spectroscopy,respectively.The results show that single(200)-oriented TiN thin films can be obtained at a wide range of substrate temperature from 200 to 600 ℃ with the grain size increasing from 35.9 to 64.5 nm.The resistivity of the product is as low as95 μΩ·cm,and the value of the optical reflectance is above68 % in the near-infrared(NIR) range of 760-1500 nm.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 61974144, 62004127, and 12074263)Key-Area Research and Development Program of Guangdong Province (Grant Nos. 2020B010174003 and 2020B010169001)+2 种基金Guangdong Science Foundation for Distinguished Young Scholars (Grant No. 2022B1515020073)the Science and Technology Foundation of Shenzhen (Grant No. JSGG20191129114216474)the Open Project of State Key Laboratory of Functional Materials for Informatics。
文摘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.
基金This work was supported by the National Natural Science Foundation of China(No,50376067)the Plan for Science&Technology Development of Guangzhou(2001-Z-117-01).
文摘TiO2 thin film has attracted considerable attention in recent years, due to its different refractive index and transparency with amorphous and different crysta ls in the visible and near-infrared wavelength region, high dielectric constant, wide band gap, high wear resistance and stability, etc, for which make it being used in many fields. This paper aims to investigate the optical characterizatio n of thin film TiO2 on silicon wafer. The TiO2 thin films were prepared by DC re active magnetron sputtering process from Ti target. The reflectivity of the film s was measured by UV-3101PC, and the index of refraction (n) and extinction coef ficient (k) were measured by n & k Analyzer 1200.
文摘Carbon nitride thin films were deposited on Si(001) using unbalanced magnetron sputtering at different experimental parameters. The effects of nitrogen partial pressure, substrate temperature and substrate bias on the deposition rate and nitrogen content are discussed.
基金Sponsored by the National Natural Science Foundation of China ( Grant No. 50525204 and 50832001)the special Ph.D. Program ( Grant No.200801830025) from MOE+2 种基金the "211" and "985" Project of Jilin University, Chinathe program for Changjiang Scholars and Innovative Research Teamin UniversityScience Frontier and Cross-disciplinary Innovation Project of Jilin University, China (Grant No. 200903022)
文摘To explore the relationship between the chemical bonding and mechanical properties for germanium carbide (Ge1-xCx) films,the Ge1-xCx films are prepared via reactive magnetron sputtering in a mixture of CH4/Ar discharge,and their composition,chemical bonding and hardness were investigated as a function of substrate temperature (Ts). The results show that Ts remarkably influences the chemical bonding of Ge1-xCx film,which results in a pronounced change in the film hardness. As Ts increases from ambient (60 ℃) to 500 ℃,the Ge content in the film gradually increases,which promotes forming sp3 C-Ge bonds in the film at the expense of sp2C-C bonds. Furthermore,it is found that with increasing Ts the fraction of C-H bonds in Ge1-xCx film gradually decreases,which is attributed to an enhancement in the desorption rate of C-Hn(n=1,2,3) species decomposed from methane. The transition from graphite-like sp2 C-C to diamond-like sp3C-Ge bonds as well as the reduction in C-H bonds in the film with increasing Ts promotes forming the compact three-dimensional network structure,which significantly enhances the hardness of the film from 5.8 to 10.1 GPa.
文摘The TiN coatings on the surfaces of various cemented carbides were performed by use of reactive magnetron sputtering.Thehighest microhardness which was obtained in our experiment was 49 GPa.The order of effect weights of deposition parameters isP_∑,β,Ts,...,which resulted from the LI6 experiments according to orthogonal design.The pole density analysis indicated thatthere were a few of the textureless samples.The crystal orientation of TiN exhibited clear regularity and affected microhardnessand other properties of films remarkably.A concept relating to structure factor was proposed.A layer-like structure was found.SAES showed that a transition layer exists between substrate and coating and its thickness is of the order of micron.The forma-tion mechanism of film was discussed.
基金Project supported by the Department of Science and TechnologyGovernment of India and Council of Scientific and Industrial ResearchIndia
文摘In order to make sufficient use of reactive cylindrical magnetron plasma for depositing compound thin films, it is necessary to characterize the hysteresis behavior of the discharge. Cylindrical magnetron plasmas with different targets namely titanium and aluminium are studied in an argon/oxygen and an argon/nitrogen gas environment respectively. The aluminium and titanium emission lines are observed at different flows of reactive gases. The emission intensity is found to decrease with the increase of the reactive gas flow rate. The hysteresis behavior of reactive cylindrical magnetron plasma is studied by determining the variation of discharge voltage with increasing and then reducing the flow rate of reactive gas,while keeping the discharge current constant at 100 m A. Distinct hysteresis is found to be formed for the aluminium target and reactive gas oxygen. For aluminium/nitrogen, titanium/oxygen and titanium/nitrogen, there is also an indication of the formation of hysteresis; however, the characteristics of variation from metallic to reactive mode are different in different cases. The hysteresis behaviors are different for aluminium and titanium targets with the oxygen and nitrogen reactive gases, signifying the difference in reactivity between them. The effects of the argon flow rate and magnetic field on the hysteresis are studied and explained.
基金supported by CONACYT-Frontera-1740,CONACy T-CB-288101,CONACy T-299703,and DGAPAPAPIIT-IN101419 projectssupport from the CONACYT Ph.D.-scholarship(CVU 606030)+2 种基金the program Doctorado en Ciencia e Ingeniería de Materials at the Universidad Nacional Autónoma de Méxicothe support from the program Maestría y Doctorado en Ciencias Médicas,Odontológicas y de la Salud at the Universidad Nacional Autónoma de México and the Ph.D.scholarship from CONACy T(CVU 856985)the support from the program Posgrado de Doctorado en Ciencias en Biomedicina y Biotecnología Molecular,Escuela Nacional de Ciencias Biológicas at the Instituto Politécnico Nacional and the Ph.D.scholarship from CONACy T(CVU 739515)
文摘Biodegradable magnesium alloys are promising candidates for temporary fracture fixation devices in orthopedics;nevertheless,its fast degradation rate at the initial stage after implantation remains as one of the main challenges to be resolved.ZrO_(2)-based coatings to reduce the degradation rate of the Mg-implants are an attractive solution since they show high biocompatibility and stability.In this work,the degradation,cytotoxicity,and antibacterial performance of ZrO_(2)thin films deposited by magnetron sputtering on a Mg-Zn-Ca alloy was evaluated.Short-term degradation of ZrO_(2)-coated and uncoated samples was assessed considering electrochemical techniques and H_(2)evolution(gas chromatography).Additionally,long term degradation was assessed by mass-loss measurements.The results showed that a 380 nm ZrO_(2)coating reduces the degradation rate and H_(2)evolution of the alloy during the initial 3 days after immersion but allows the degradation of the bare alloy for the long-term.The ZrO_(2)coating does not compromise the biocompatibility of the alloy and permits better cell adhesion and proliferation of mesenchymal stem cells directly on its surface,in comparison to the bare alloy.Finally,the ZrO_(2)coating prevents the adhesion and biofilm formation of S.aureus.
基金Project supported by the National Natural Science Foundation of China (Grant No. 60807001)the Foundation of Henan Educational Committee,China (Grant No. 2010A140017)the National Basic Research Program of China (Grant No. 2011CB201605)
文摘Using a radio-frequency reactive magnetron sputtering technique,a series of the single-phased Ag2O films are deposited in a mixture of oxygen and argon gas with a flow ratio of 2:3 by changing substrate temperature(T s).Effects of the T s on the microstructure and optical properties of the films are investigated by using X-ray diffractometry,scanning electron microscopy and spectrophotometry.The single-phased Ag2O films deposited at values of T s below 200℃ are(111) preferentially oriented,which may be due to the smallest free energy of the(111) crystalline face.The film crystallization becomes poor as the value of T s increases from 100℃ to 225℃.In particular,the Ag2O film deposited at T s = 225℃ loses the 111 preferential orientation.Correspondingly,the film surface morphology obviously evolves from a uniform and compact surface structure to a loose and gullied surface structure.With the increase of T s value,the transmissivity and the reflectivity of the films in the transparent region are gradually reduced,while the absorptivity gradually increases,which may be attributed to an evolution of the crystalline structure and the surface morphology of the films.
基金supported by the National Natural Science Foundation of China (Grant No. 60807001)the National Basic Research Program of China (Grant No. 2011CB201605)the Foundation of Henan Educational Committee (Grant No. 2010A140017)
文摘This paper reports that a series of silver oxide (Ag x O) films are deposited on glass substrates by direct-current reactive magnetron sputtering at a substrate temperature of 250 C and an oxygen flux ratio of 15:18 by modifying the sputtering power (SP).The Ag x O films deposited apparently show a structural evolution from cubic biphased (AgO + Ag 2 O) to cubic single-phased (Ag 2 O),and to biphased (Ag 2 O + AgO) structure.Notably,the cubic single-phased Ag 2 O film is deposited at the SP=105 W and an AgO phase with 220 orientation discerned in the Ag x O films deposited using the SP > 105 W.The transmissivity and reflectivity of the Ag x O films in transparent region decrease with the increase the SP,whereas the absorptivity inversely increases with the increase of the SP.These results may be due to the structural evolution and the increasing film thickness.A redshift of the films' absorption edges determined in terms of Tauc formula clearly occurs from 3.1 eV to 2.73 eV with the increase of the SP.
文摘TiZrN films were deposited on unheated Si (100) substrates by reactive dc magnetron co-sputtering. Titanium and zirconium metals were used as sputtering targets. Ar and N2 gas were used as sputtering gas and reactive gas, with the flow rates of 8 and 4 sccm, respectively. The Zr sputtering current was fixed at 0.6 A and Ti sputtering current varied from 0.6 to 1.2 A. The deposition time for all the deposited films was 60 min. The effects of Ti sputtering current on the structure and morphology of the films were investigated by X-ray diffraction (XRD), atomic force microscopy (AFM), field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). It was found that all the prepared films were (Ti,Zr)N solid solution. Furthermore, the lattice parameter was found to decrease whereas the crystallite size, RMS roughness and film thickness increased with increasing Ti sputtering current. As a result, the crystallinity of the films increased what is in agreement with XRD results.
基金the National Natural Science Foundation of China (No.10574047)the Key Program of the Education Branch of Hubei Province of China (No. D200529002)
文摘Cu3N and AlxCu3N films were prepared with reactive magnetron sputtering method. The two films were deposited on glass substrates at 0.8 Pa N2 partial pressure and 100 ℃ substrate temperature by using a pure Cu and Al target,respectively. X-ray diffraction (XRD) measurements show that the un-doped film was composed of Cu3N crystallites with anti-ReO3 structure and adopted 111 preferred orientation. XRD shows that t he growth of Al-doped copper nitride films (AlxCu3N) was affected strongly by doping Al,the intensity of 111 peak decreases with increasing the concentration of Al and the high concentration of Al could prevent the Cu3N f rom crystallization. AFM shows that the surface of AlxCu3N film is smoother than that of Cu3N film. Compared w ith the Cu3N films,the resistivities of the Al-doped copper nitride films (AlxCu3N) have been reduced,and the microhardness has been enhanced.
基金supported by the“985”program of the Ministry of Education
文摘ZrO2 thin films were deposited by r.f. reactive unbalanced magnetron sputtering. The influence of electromagnetic coil current on microstructure and optical properties of the films was investigated. At low coil current of 0.2A, small grains are produced. With the increase of coil current, the deposition rate and surface roughness are decreased and the packing density in proportion to the refractive index is increased remarkably. The refractive index is as high as 2.236 (at X=600nm) at 0.4A. At the high coil current of 0.6A, grains appear to grow up due to thermal effects and therefore optical properties of the films are deteriorated a little.
