The one-dimensional photonic crystals of Ag/SiO_(2) system are studied to investigate the photonic band gaps (PBG). The samples were prepared by the ultra-high vacuum electron beam evaporation. The clear band gaps wer...The one-dimensional photonic crystals of Ag/SiO_(2) system are studied to investigate the photonic band gaps (PBG). The samples were prepared by the ultra-high vacuum electron beam evaporation. The clear band gaps were observed. Satisfactory agreement between experimental and calculated results was obtained without fitting. The thickness of SiO_(2 )film has influence on the photonic band gap, as well as it awfully affects the transmittance of Ag. More layers can get clearer PBG.展开更多
We investigated the effects of Si-layer-thickness ratios on ultraviolet (UV) peak intensities of Si/ SiO2 multilayered films produced by alternately stacking several-nanometer-thick Si and SiO2 layers using radio-freq...We investigated the effects of Si-layer-thickness ratios on ultraviolet (UV) peak intensities of Si/ SiO2 multilayered films produced by alternately stacking several-nanometer-thick Si and SiO2 layers using radio-frequency sputtering for the first time. The Si-layer-thickness ratio of the Si/SiO2 film is a very important parameter for enhancing the peak intensity because the ratio is concerned with the size of Si nanocrystals in the film, which might affect the intensity of the UV light emission from the film. We prepared seven samples with various estimated Si-layer-thickness ratios, and measured the photoluminescence spectra of the samples after annealing at 1150°C, 1200°C, or 1250°C for 25 min. From our experiments, we estimate that the proper Si-layer-thickness ratio to obtain the strongest UV peaks from the Si/SiO2 multilayered films is around 0.29. Such a UV-lightemitting thin film is expected to be used in future higher-density optical-disk systems.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
The effects of Ag layers with different locations and thicknesses on the structural and magnetic property of SiO2/FePt multilayer films were investigated.The non-magnetic Ag layer plays an important role in inducing(...The effects of Ag layers with different locations and thicknesses on the structural and magnetic property of SiO2/FePt multilayer films were investigated.The non-magnetic Ag layer plays an important role in inducing(001) orientation and ordering of FePt grains,as well as the SiO2-doping reducing the grain size and the magnetic exchange coupling between grains.When the 10 nm Ag layer is moved from the bottom to the top of the SiO2/FePt multilayer film,the coercivity gradually decreases;the largest difference between the out-of-plane coercivity and the in-plane one is obtained in the sample of [SiO2(2 nm)/FePt(3 nm)]3/Ag(10 nm)/[SiO2(2 nm)/FePt(3 nm)]2.Furthermore,the location of Ag layers was fixed and the thickness was changed.The XRD curves suggest that the intensity of the(001) peak becomes the strongest with the addition of 10 nm Ag layers.展开更多
Nanosecond single- and multiple-pulse laser damage studies on HfOffSiO2 high-reflection (HR) coatings are performed at 532 nm. For single-pulse irradiation, the damage is attributed to the defects and the electric i...Nanosecond single- and multiple-pulse laser damage studies on HfOffSiO2 high-reflection (HR) coatings are performed at 532 nm. For single-pulse irradiation, the damage is attributed to the defects and the electric intensity distribution in the multilayer thin films. When the defect density in the irradiated area is high, delami- nation is observed. Other than the 1064 nm laser damage, the plasma scalding of the 532 nm laser damage is not pits-centered for normal incidence, and the size of the plasma scalding has no relation to the defect density and position, but increases with the laser fluence. For multiple-pulse irradiations, some damage sites show deeper precursors than those from the single-shot irradiation due to the accumulation effects. The cumulative laser- induced damages behave as pits without the presence of plasma scalding, which is unaffected by the laser fluence and shot numbers. The damage morphologies and depth information both confirm the fatigue effect of a HfO2/SiO2 HR coating under 532 nm laser irradiation.展开更多
太阳能的应用是解决能源与环境问题的有效途径,而高转换效率低成本,易于产业化的高效电池技术是太阳电池发展的目标。近年来高转换效率技术层出不穷,例如SE电池(Selective emitter Cell),MWT电池(Metal warp through cell)和EWT电池(Emi...太阳能的应用是解决能源与环境问题的有效途径,而高转换效率低成本,易于产业化的高效电池技术是太阳电池发展的目标。近年来高转换效率技术层出不穷,例如SE电池(Selective emitter Cell),MWT电池(Metal warp through cell)和EWT电池(Emitter Warp through cell)等。这些高效电池均采用了良好的钝化技术。而常规晶硅太阳电池由于没有采用背场钝化技术,只使用铝背场,而经过烧结形成的铝硅合金背表面在减少复合和背反射效果方面有很大的局限性,并且铝硅合金区本身即高复合区,限制了电池效率的进一步提高。因此为了进一步提高开路电压及短路电流,对硅基背表面进行钝化是很有必要的。通过试验,着重比较了SiNx背场钝化层和SiO2背场钝化层对电池电性参数的影响和变化趋势。通过对电池片IQE分析发现,在使用了SiO2或SiNx背场钝化层后,长波区域的IQE响应相比正常电池片有明显提升,说明SiO2或SiNx确实起到钝化作用。而再对电性参数分析后发现,SiO2与SiNx相比可以有效提高电池的Rsh,降低反向电流。同时在EFF测试方面,SiO2与SiNx相比,也具有一定的优势。展开更多
基金Supported by the National High Technology Development Program of China(Grant No.2003AA32720)Shanghai Nanotechnology Promotion Center(0352nm016, 0359nm204,0252nm084)+2 种基金Science and Technology Council of Shanghai(03dz11009)Fore-research of basic research project(2001CCA02800)the special Foundation for State Major Basic Research Programmeof China(Grant No.001CB610408)
文摘The one-dimensional photonic crystals of Ag/SiO_(2) system are studied to investigate the photonic band gaps (PBG). The samples were prepared by the ultra-high vacuum electron beam evaporation. The clear band gaps were observed. Satisfactory agreement between experimental and calculated results was obtained without fitting. The thickness of SiO_(2 )film has influence on the photonic band gap, as well as it awfully affects the transmittance of Ag. More layers can get clearer PBG.
文摘We investigated the effects of Si-layer-thickness ratios on ultraviolet (UV) peak intensities of Si/ SiO2 multilayered films produced by alternately stacking several-nanometer-thick Si and SiO2 layers using radio-frequency sputtering for the first time. The Si-layer-thickness ratio of the Si/SiO2 film is a very important parameter for enhancing the peak intensity because the ratio is concerned with the size of Si nanocrystals in the film, which might affect the intensity of the UV light emission from the film. We prepared seven samples with various estimated Si-layer-thickness ratios, and measured the photoluminescence spectra of the samples after annealing at 1150°C, 1200°C, or 1250°C for 25 min. From our experiments, we estimate that the proper Si-layer-thickness ratio to obtain the strongest UV peaks from the Si/SiO2 multilayered films is around 0.29. Such a UV-lightemitting thin film is expected to be used in future higher-density optical-disk systems.
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.
基金supported by the National Natural Science Foundation of China(Nos.10574085 and 60776008)the Science Technology Key Project of the Ministry of Education of China(No.207020).
文摘The effects of Ag layers with different locations and thicknesses on the structural and magnetic property of SiO2/FePt multilayer films were investigated.The non-magnetic Ag layer plays an important role in inducing(001) orientation and ordering of FePt grains,as well as the SiO2-doping reducing the grain size and the magnetic exchange coupling between grains.When the 10 nm Ag layer is moved from the bottom to the top of the SiO2/FePt multilayer film,the coercivity gradually decreases;the largest difference between the out-of-plane coercivity and the in-plane one is obtained in the sample of [SiO2(2 nm)/FePt(3 nm)]3/Ag(10 nm)/[SiO2(2 nm)/FePt(3 nm)]2.Furthermore,the location of Ag layers was fixed and the thickness was changed.The XRD curves suggest that the intensity of the(001) peak becomes the strongest with the addition of 10 nm Ag layers.
基金supported by the National Natural Science Foundation of China under Grant Nos.11104293and 61308021
文摘Nanosecond single- and multiple-pulse laser damage studies on HfOffSiO2 high-reflection (HR) coatings are performed at 532 nm. For single-pulse irradiation, the damage is attributed to the defects and the electric intensity distribution in the multilayer thin films. When the defect density in the irradiated area is high, delami- nation is observed. Other than the 1064 nm laser damage, the plasma scalding of the 532 nm laser damage is not pits-centered for normal incidence, and the size of the plasma scalding has no relation to the defect density and position, but increases with the laser fluence. For multiple-pulse irradiations, some damage sites show deeper precursors than those from the single-shot irradiation due to the accumulation effects. The cumulative laser- induced damages behave as pits without the presence of plasma scalding, which is unaffected by the laser fluence and shot numbers. The damage morphologies and depth information both confirm the fatigue effect of a HfO2/SiO2 HR coating under 532 nm laser irradiation.
文摘太阳能的应用是解决能源与环境问题的有效途径,而高转换效率低成本,易于产业化的高效电池技术是太阳电池发展的目标。近年来高转换效率技术层出不穷,例如SE电池(Selective emitter Cell),MWT电池(Metal warp through cell)和EWT电池(Emitter Warp through cell)等。这些高效电池均采用了良好的钝化技术。而常规晶硅太阳电池由于没有采用背场钝化技术,只使用铝背场,而经过烧结形成的铝硅合金背表面在减少复合和背反射效果方面有很大的局限性,并且铝硅合金区本身即高复合区,限制了电池效率的进一步提高。因此为了进一步提高开路电压及短路电流,对硅基背表面进行钝化是很有必要的。通过试验,着重比较了SiNx背场钝化层和SiO2背场钝化层对电池电性参数的影响和变化趋势。通过对电池片IQE分析发现,在使用了SiO2或SiNx背场钝化层后,长波区域的IQE响应相比正常电池片有明显提升,说明SiO2或SiNx确实起到钝化作用。而再对电性参数分析后发现,SiO2与SiNx相比可以有效提高电池的Rsh,降低反向电流。同时在EFF测试方面,SiO2与SiNx相比,也具有一定的优势。