The crystalline structure and surface morphology of TiO2 semiconductor coating play an important role in the conversion efficiency of dye-sensitized solar cells. In order to obtain TiO2 coating with controllable morph...The crystalline structure and surface morphology of TiO2 semiconductor coating play an important role in the conversion efficiency of dye-sensitized solar cells. In order to obtain TiO2 coating with controllable morphology and high porosity, nanoporous TiO2 films were fabricated on conducting glass (FTO) substrates, Ti thin films (1.5-2 gin) were deposited on conducting glass (FTO) substrates via the DC sputtering method, and then electrochemically anodized in NH4F/ethylene glycol solution. The crystalline structure and surface morphology of the samples were characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM), respectively. The influences of anodizing potential, electrolyte composition, and pH value on the surface morphology of nanoporous TiO2 films were extensively studied. The growth mechanism of nanoporous TiO2 films was discussed by current density variations with anodizing time. The results demonstrate that nanoporous TiO2 films with high porosity and three-dimensional (3D) networks are observed at 30 V, when the NH4F concentration in ethylene glycol solution is 0.3% (mass fraction) and the electrolyte pH value is 5.0.展开更多
Sb-doped SnO2(ATO)-(CeO2-TiO2) thin Films were deposited on glass substrates using the mixed solution including CeO2-TiO2 precursor and ATO particles by sol-gel dip coating process.ATO particles were prepared using lo...Sb-doped SnO2(ATO)-(CeO2-TiO2) thin Films were deposited on glass substrates using the mixed solution including CeO2-TiO2 precursor and ATO particles by sol-gel dip coating process.ATO particles were prepared using low-temperature hydrothermal process.The mixed molar ratio of ATO to(CeO2-TiO2) vs the properties of CeO2-TiO2 thin film was investigated.The optical properties of the films were characterized by UV-visible transmission and infrared reflection spectra,the sheet resistance of ATO particles and films were measured by rubber sheeter(MYI-50) and four-point probe(HisuperGroup Inc,SDY-5),the surface morphology and structure of the films were analyzed using 3D Digitale Mikroskop and X-ray diffraction(XRD),respectively.The results showed that the ATO precursor solution lost weight completely at about 500 oC,and the ATO particles was obtained,which indicated the same rutile lattice structure as SnO2.The glass substrates coated with ATO-(CeO2-TiO2) thin films showed better properties in antistatic electricity(104-106 Ω/),shielding UV(almost 100%),visible light transmission(70%) and infrared reflection(】30%).展开更多
CeO2-TiO2 films and CeO2-TiO/SnO2:Sb (6 mol%) double films were deposited on glass substrates by radio-frequency magnetron sputtering (R.F. Sputtering), using SnO2:Sb(6 mol%) target, and CeO2- TiO2 targets wit...CeO2-TiO2 films and CeO2-TiO/SnO2:Sb (6 mol%) double films were deposited on glass substrates by radio-frequency magnetron sputtering (R.F. Sputtering), using SnO2:Sb(6 mol%) target, and CeO2- TiO2 targets with different molar ratio of CeO2 to TiO2 (CeO2:TiO2-0:1.0; 0.1:0.9; 0.2:0.8; 0.3:0.7; 0.4:0.6; 0.5:0.5; 0.6:0.4; 0.7:0.3; 0.8:0.2; 0.9:0.1; 1.0:0). The films are characterized by UV-visible transmission and infrared reflection spectra, scanning electron microscopy (SEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD), respectively. The obtained results show that the amorphous phases composed of CeO2-TiO2 play an important role in absorbing UV, there are Ce^3-, Ce^4- and Ti^4- on the surface of the films; the glass substrates coated with CeO2-TiO2 (Ce/Ti=0.5:0.5; 0.6:0.4)/SnO2:Sb(6 mol%) double films show high absorbing UV(〉99), high visible light transmission (75%) and good infrared reflection (〉70%). The sheet resistance of the films is 30-50 Ω/□. The glass substrates coated with the double functional films can be used as window glass of buildings, automobile and so on.展开更多
Fe2O3/SiO2 nano-composite films were prepared by sol-gel technique combining heat treatment in the range of 100-900 ℃. The particle size was observed by FE-SEM. Optical properties of the films were investigated by UV...Fe2O3/SiO2 nano-composite films were prepared by sol-gel technique combining heat treatment in the range of 100-900 ℃. The particle size was observed by FE-SEM. Optical properties of the films were investigated by UV-visible spectra. Structural and magnetic characteristics were investigated through FT-IR and VSM. The transparency of the Fe2O3/SiO2 nano-composite films decreased with the content of the Fe2O3. Water and organic solvent in the films were evaporated with heat treatment, so the transparency of the films was enhanced under high temperature. It is also found that the saturation magnetization (Ms) of the films increases with the temperature. As the content of the Fe2O3 increases, when the content of the Fe2O3 is around 30wt%, the Ms of the films has a maximum value.展开更多
[SiO2/FePt]5/Ag thin films were deposited by RF magnetron sputtering on the glass substrates and post annealing at 550 ℃ for 30 min in vacuum. Vibrating sample magnetometer and X-ray diffraction analyser were applied...[SiO2/FePt]5/Ag thin films were deposited by RF magnetron sputtering on the glass substrates and post annealing at 550 ℃ for 30 min in vacuum. Vibrating sample magnetometer and X-ray diffraction analyser were applied to study the magnetic properties and microstructures of the films. The results show that without Ag underlayer [SiO2/FePt]5 films deposited onto the glass are FCC disordered; with the addition of Ag underlayer [SiO]FePt]5/Ag films are changed into L10 and (111) mixed texture. The variation of the SiO2 nonmagnetic layer thickness in [SiO2/FePt]5/Ag films indicates that SiO2-doping plays an important role in improving the order parameter and the perpendicular magnetic anisotropy, and reducing the grain size and intergrain interactions. By controlling SiO2 thickness the highly perpendicular magnetic anisotropy can be obtained in the [SiO2 (0.6 nm)/FePt (3 nm)]5/Ag (50 nm) films and highly (001)-oriented films can be obtained in the [SiO2 (2 nm)/FePt (3 nm)]5/Ag (50 nm) films.展开更多
Total dose effects and single event effects on radiation-hardened power vertical double-diffusion metal oxide semiconductor(VDMOS) devices with composite SiO2-Si3N4 film gates are investigated.The relationships amon...Total dose effects and single event effects on radiation-hardened power vertical double-diffusion metal oxide semiconductor(VDMOS) devices with composite SiO2-Si3N4 film gates are investigated.The relationships among the important electrical parameters of the samples with different thickness SiO2-Si3N4 films,such as threshold voltage,breakdown voltage,and on-state resistance in accumulated dose,are discussed.The total dose experiment results show that the breakdown voltage and the on-state resistance barely change with the accumulated dose.However,the relationships between the threshold voltages of the samples and the accumulated dose are more complex,and not only positively drift,but also negatively drift.At the end of the total dose experiment,we select the group of samples which have the smaller threshold voltage shift to carry out the single event effect studies.We find that the samples with appropriate thickness ratio SiO2-Si3N4 films have a good radiation-hardening ability.This method may be useful in solving both the SEGR and the total dose problems with the composite SiO2-Si3N4 films.展开更多
基金Projects(21171027,50872014) supported by the National Natural Science Foundation of ChinaProject(K1001020-11)supported by the Science and Technology Key Project of Changsha City,China
文摘The crystalline structure and surface morphology of TiO2 semiconductor coating play an important role in the conversion efficiency of dye-sensitized solar cells. In order to obtain TiO2 coating with controllable morphology and high porosity, nanoporous TiO2 films were fabricated on conducting glass (FTO) substrates, Ti thin films (1.5-2 gin) were deposited on conducting glass (FTO) substrates via the DC sputtering method, and then electrochemically anodized in NH4F/ethylene glycol solution. The crystalline structure and surface morphology of the samples were characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM), respectively. The influences of anodizing potential, electrolyte composition, and pH value on the surface morphology of nanoporous TiO2 films were extensively studied. The growth mechanism of nanoporous TiO2 films was discussed by current density variations with anodizing time. The results demonstrate that nanoporous TiO2 films with high porosity and three-dimensional (3D) networks are observed at 30 V, when the NH4F concentration in ethylene glycol solution is 0.3% (mass fraction) and the electrolyte pH value is 5.0.
基金Project supported by the Changjiang Scholars and Innovative Research Team in University
文摘Sb-doped SnO2(ATO)-(CeO2-TiO2) thin Films were deposited on glass substrates using the mixed solution including CeO2-TiO2 precursor and ATO particles by sol-gel dip coating process.ATO particles were prepared using low-temperature hydrothermal process.The mixed molar ratio of ATO to(CeO2-TiO2) vs the properties of CeO2-TiO2 thin film was investigated.The optical properties of the films were characterized by UV-visible transmission and infrared reflection spectra,the sheet resistance of ATO particles and films were measured by rubber sheeter(MYI-50) and four-point probe(HisuperGroup Inc,SDY-5),the surface morphology and structure of the films were analyzed using 3D Digitale Mikroskop and X-ray diffraction(XRD),respectively.The results showed that the ATO precursor solution lost weight completely at about 500 oC,and the ATO particles was obtained,which indicated the same rutile lattice structure as SnO2.The glass substrates coated with ATO-(CeO2-TiO2) thin films showed better properties in antistatic electricity(104-106 Ω/),shielding UV(almost 100%),visible light transmission(70%) and infrared reflection(】30%).
基金the program for Changjiang Scholars and Innovative Research Team in University (No.IRT0547
文摘CeO2-TiO2 films and CeO2-TiO/SnO2:Sb (6 mol%) double films were deposited on glass substrates by radio-frequency magnetron sputtering (R.F. Sputtering), using SnO2:Sb(6 mol%) target, and CeO2- TiO2 targets with different molar ratio of CeO2 to TiO2 (CeO2:TiO2-0:1.0; 0.1:0.9; 0.2:0.8; 0.3:0.7; 0.4:0.6; 0.5:0.5; 0.6:0.4; 0.7:0.3; 0.8:0.2; 0.9:0.1; 1.0:0). The films are characterized by UV-visible transmission and infrared reflection spectra, scanning electron microscopy (SEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD), respectively. The obtained results show that the amorphous phases composed of CeO2-TiO2 play an important role in absorbing UV, there are Ce^3-, Ce^4- and Ti^4- on the surface of the films; the glass substrates coated with CeO2-TiO2 (Ce/Ti=0.5:0.5; 0.6:0.4)/SnO2:Sb(6 mol%) double films show high absorbing UV(〉99), high visible light transmission (75%) and good infrared reflection (〉70%). The sheet resistance of the films is 30-50 Ω/□. The glass substrates coated with the double functional films can be used as window glass of buildings, automobile and so on.
基金Funded by the Innovative Program of Shanghai Municipal Education Commission (No.08YZ97)the National Natural Science Foundation of China (No.10704048)
文摘Fe2O3/SiO2 nano-composite films were prepared by sol-gel technique combining heat treatment in the range of 100-900 ℃. The particle size was observed by FE-SEM. Optical properties of the films were investigated by UV-visible spectra. Structural and magnetic characteristics were investigated through FT-IR and VSM. The transparency of the Fe2O3/SiO2 nano-composite films decreased with the content of the Fe2O3. Water and organic solvent in the films were evaporated with heat treatment, so the transparency of the films was enhanced under high temperature. It is also found that the saturation magnetization (Ms) of the films increases with the temperature. As the content of the Fe2O3 increases, when the content of the Fe2O3 is around 30wt%, the Ms of the films has a maximum value.
基金Project(10574085) supported by the National Natural Science Foundation of ChinaProject(207020) supported by the Science Technology Key Project of the Ministry of Education, China
文摘[SiO2/FePt]5/Ag thin films were deposited by RF magnetron sputtering on the glass substrates and post annealing at 550 ℃ for 30 min in vacuum. Vibrating sample magnetometer and X-ray diffraction analyser were applied to study the magnetic properties and microstructures of the films. The results show that without Ag underlayer [SiO2/FePt]5 films deposited onto the glass are FCC disordered; with the addition of Ag underlayer [SiO]FePt]5/Ag films are changed into L10 and (111) mixed texture. The variation of the SiO2 nonmagnetic layer thickness in [SiO2/FePt]5/Ag films indicates that SiO2-doping plays an important role in improving the order parameter and the perpendicular magnetic anisotropy, and reducing the grain size and intergrain interactions. By controlling SiO2 thickness the highly perpendicular magnetic anisotropy can be obtained in the [SiO2 (0.6 nm)/FePt (3 nm)]5/Ag (50 nm) films and highly (001)-oriented films can be obtained in the [SiO2 (2 nm)/FePt (3 nm)]5/Ag (50 nm) films.
文摘Total dose effects and single event effects on radiation-hardened power vertical double-diffusion metal oxide semiconductor(VDMOS) devices with composite SiO2-Si3N4 film gates are investigated.The relationships among the important electrical parameters of the samples with different thickness SiO2-Si3N4 films,such as threshold voltage,breakdown voltage,and on-state resistance in accumulated dose,are discussed.The total dose experiment results show that the breakdown voltage and the on-state resistance barely change with the accumulated dose.However,the relationships between the threshold voltages of the samples and the accumulated dose are more complex,and not only positively drift,but also negatively drift.At the end of the total dose experiment,we select the group of samples which have the smaller threshold voltage shift to carry out the single event effect studies.We find that the samples with appropriate thickness ratio SiO2-Si3N4 films have a good radiation-hardening ability.This method may be useful in solving both the SEGR and the total dose problems with the composite SiO2-Si3N4 films.