CdTe/CdS quantum dots（QDs） are fabricated on Si nanowires（NWs） substrates with and without Au nanoparticles（NPs）. The formation of Au NPs on Si NWs can be certified as shown in scanning electron microscopy image...CdTe/CdS quantum dots（QDs） are fabricated on Si nanowires（NWs） substrates with and without Au nanoparticles（NPs）. The formation of Au NPs on Si NWs can be certified as shown in scanning electron microscopy images. The optical properties of samples are also investigated. It is interesting to find that the photoluminescence（PL） intensity of Cd Te/Cd S QD films on Si nanowire substrates with Au NPs is significantly increased,which can reach 8-fold higher than that of samples on planar Si without Au NPs. The results of finite-difference time-domain simulation indicate that Au NPs induce stronger localization of electric field and then boost the PL intensity of QDs nearby. Furthermore, the time-resolved luminescence decay curve shows the PL lifetime, which is about 5.5 ns at the emission peaks of QD films on planar, increasing from 1.8 ns of QD films on Si NWs to4.7 ns after introducing Au NPs into Si NWs.展开更多
Structure and properties of anti-reflection thin films of spherical silicon solar cells were investigated and discussed. Conversion efficiencies of spherical Si solar cells coated with F-doped SnO2 anti-reflection fil...Structure and properties of anti-reflection thin films of spherical silicon solar cells were investigated and discussed. Conversion efficiencies of spherical Si solar cells coated with F-doped SnO2 anti-reflection films were improved by annealing. Optical absorption and fluorescence of the solar cells increased after annealing. Lattice constants of F-doped SnO2 anti-reflection layers, which were investigated by X-ray diffraction, decreased after annealing. A mechanism of atomic diffusion of F in SnO2 was discussed. The present work indicated a guideline for spherical silicon solar cells with higher efficiencies.展开更多
Perovskite solar cells have shown great potential in the field of underwater solar cells due to their excellent optoelectronic properties;however,their underwater performance and stability still hinder their practical...Perovskite solar cells have shown great potential in the field of underwater solar cells due to their excellent optoelectronic properties;however,their underwater performance and stability still hinder their practical use.In this research,a 1H,1H,2H,2H-heptadecafluorodecyl acrylate(HFDA)anti-reflection coating(ARC)was introduced as a high-transparent material for encapsulating perovskite solar modules(PSMs).Optical characterization results revealed that HFDA can effectively reduce reflection of light below 800 nm,aiding in the absorption of light within this wavelength range by underwater solar cells.Thus,a remarkable efficiency of 14.65%was achieved even at a water depth of 50 cm.And,the concentration of Pb^(2+)for HFDA-encapsulated film is significantly reduced from 186 to 16.5 ppb after being immersed in water for 347 h.Interestingly,the encapsulated PSMs still remained above 80%of their initial efficiency after continuous underwater illumination for 400 h.Furthermore,being exposed to air,the encapsulated PSMs maintained 94%of their original efficiency after 1000 h light illumination.This highly transparent ARC shows great potentials in enhancing the stability of perovskite devices,applicable not only to underwater cells but also extendable to land-based photovoltaic devices.展开更多
Perovskite solar cells(PSCs)have been receiving attention for photovoltaic advantages of high-power conversion efficiency,cost-effectiveness,and easy fabrication process.Particularly,flexible PSCs(FPSCs)are considered...Perovskite solar cells(PSCs)have been receiving attention for photovoltaic advantages of high-power conversion efficiency,cost-effectiveness,and easy fabrication process.Particularly,flexible PSCs(FPSCs)are considered to be promising renewable power sources due to the positive potential of flexible and lightweight properties.However,FPSCs tend to have lower efficiency compared to glass-based rigid PSCs(RPSCs).The main issue is high refractive index of polymer substrates such as polyethylene naphthalate(PEN),used for FPSCs,thereby reducing the external light absorption efficiency.In this study,we developed glasswing inspired sticker-type multilayer anti-reflective(GSMA)film derived from the wings of the glasswing butterfly to enhance the light absorption efficiency of FPSCs.We designed and fabricated the GSMA film with multilayers specifically for FPSCs.The suitable materials and nanostructures to adjust the refractive index are theoretically optimized.The GSMA film effectively improved the optical properties of PSC substrates,reducing reflectance(∼5.01%)and enhancing light transmittance(∼6.17%)in indium tin oxide(ITO)/PEN.In addition,the GSMA film on PEN maintains more than 94.70%of its initial transmittance even after being exposed to various harsh environments for 500 h,and GSMA film demonstrates flexibility by maintaining its initial structure even after a bending test(bending radius of 1 mm).The FPSCs and RPSCs assisted by GSMA film show high short-circuit current density(FPSC:∼25.28 mA/cm^(2),up to 26.05 mA/cm^(2),RPSC:∼24.27 mA/cm^(2))and power conversion efficiency(FPSC:∼22.72%,RPSC:∼22.31%),significantly narrowing the efficiency gap between FPSC and RPSCs.展开更多
Complementary metal oxide semiconductor(CMOS) image sensors(CIS) are being widely used in digital video cameras, web cameras, digital single lens reflex camera(DSLR), smart phones and so on, owing to their high level ...Complementary metal oxide semiconductor(CMOS) image sensors(CIS) are being widely used in digital video cameras, web cameras, digital single lens reflex camera(DSLR), smart phones and so on, owing to their high level of integration, random accessibility, and low-power operation. It needs to be installed with the cover glass in practical applications to protect the sensor from damage, mechanical issues,and environmental conditions, which, however, limits the accuracy and usability of the sensor due to the reflection in the optical path from air-to-cover glass-to-air. In this work, the flexible 3D nanocone anti-reflection(AR) film with controlled aspect ratio was firstly employed to reduce the light reflection at air/cover glass/air interfaces by directly attaching onto the front and rear sides of the CIS cover glass.As both the front and rear sides of cover glass were coated by the AR film, the output image quality was found to be improved with external quantum efficiency increased by 7%, compared with that without AR film. The mean digital data value, root-mean-square contrast, and dynamic range are increased by45.14%, 38.61% and 57, respectively, for the output image with AR films. These results provide a novel and facile pathway to improve the CIS performance and also could be extended to rational design of other image sensors and optoelectronic devices.展开更多
An ultra-thin and broadband absorber which consists of periodic rings with gaps is proposed in this paper. The periodic rings are printed on the middle metallic layers in a four-layer substrate of total thickness is o...An ultra-thin and broadband absorber which consists of periodic rings with gaps is proposed in this paper. The periodic rings are printed on the middle metallic layers in a four-layer substrate of total thickness is only 3.4 mm. Simulation results, which are gotten by using finite element method(FEM) and finite-difference time-domain(FDTD), show that the absorption is higher than 90% cover the frequencies range from 7.8 GHz to 22.2 GHz. The measurement results of the absorption agree with simulated ones very well. We also discuss the working mechanism according to the anti-reflection theory in the paper.展开更多
Undesired reflection caused by impedance mismatch can lead to significant power loss and other unwanted effects. In the terahertz regime, anti-reflection method has evolved from simple quarter-wave antireflection coat...Undesired reflection caused by impedance mismatch can lead to significant power loss and other unwanted effects. In the terahertz regime, anti-reflection method has evolved from simple quarter-wave antireflection coating to sophisticated metamaterial device and photonic structures. In this paper, we examined and compared the theories and techniques of several antireflection implementations for terahertz waves, with emphasis on gradient index photonic structures. A comprehensive study is presented on the design, fabrication and evaluation of this new approach.展开更多
Broadband transparent films play a pivotal role in various applications such as lenses and solar cells,particularly porous structured transparent films exhibit significant potential.This study investigates a porous Si...Broadband transparent films play a pivotal role in various applications such as lenses and solar cells,particularly porous structured transparent films exhibit significant potential.This study investigates a porous SiO_(2) refractive index gradient anti-reflective film prepared by atomic layer deposition(ALD).A porous SiO_(2) film with gradual porosity was obtained by phosphoric acid etching of Al_(2)O_(3)/SiO_(2) multilayers with gradient Al2O3 ratios,achieving a gradual decrease in refractive index from the substrate to the surface.The film exhibited an average transmittance as high as 97.8%within the wavelength range from 320 nm to 1200 nm.The environmental adaptability was further enhanced by surface modification using rare earth oxide(REO)La_(2)O_(3),resulting in formation of a lotus leaf-like structure and achieving a water contact angle of 100.0°.These data proved that the modification significantly improved hydrophobic self-cleaning capability while maintaining exceptional transparency of the film.The surface structure of the modified film remained undamaged even after undergoing wipe testing,demonstrating its excellent surface durability.展开更多
Structural strengthening of the nano porous silica films has been reported. The films were prepared with a base/acid two-step catalyzed TEOS-based sol-gel processing and dip-coating, and then baked in the mixed gas of...Structural strengthening of the nano porous silica films has been reported. The films were prepared with a base/acid two-step catalyzed TEOS-based sol-gel processing and dip-coating, and then baked in the mixed gas of ammonia and water vapor. The silica films were characterized with TEM, AFM, FTIR, spectrophotometer, ellipsometer, and abrasion test, respectively. The experimental results have shown that the films have a nanostructure with a low refractive index and can form an excellent scratch-resistant broadband anti-reflectance. The two-step catalysis noticeably strengthens the films, and the mixed gas treatment further improves mechanical strength of the silica network. Finally the strengthening mechanism has been discussed.展开更多
Anti-reflective (AR) single layer of silica-titania (SiO2-TiO2) coatings were obtained from sols containing pyromellitic dianhydride (PMDA) derivatives and Ti and Si precursors on glass substrate by dip-coating method...Anti-reflective (AR) single layer of silica-titania (SiO2-TiO2) coatings were obtained from sols containing pyromellitic dianhydride (PMDA) derivatives and Ti and Si precursors on glass substrate by dip-coating method. The coatings showed very high optical quality and the transmission was improved to up to 98.5%. Furthermore, the coatings also presented good mechanical stability.展开更多
In this study, we propose the fabrication of monolithic crystalline silicon solar cells with Tb^(3+) and Yb^(3+)-doped silicon nitride(SiN_x) layers by low-cost screen-printing methods. The performances of c-Si solar ...In this study, we propose the fabrication of monolithic crystalline silicon solar cells with Tb^(3+) and Yb^(3+)-doped silicon nitride(SiN_x) layers by low-cost screen-printing methods. The performances of c-Si solar cells can be enhanced by rare-earth ions doped SiN_x layers via the mechanism of spectrum conversion.These SiN_x doped and codoped thin films were deposited by reactive magnetron co-sputtering and integrated as the antireflection coating layers in c-Si solar cells. The characterizations of SiN_x, SiN_x:Tb^(3+) tand SiN_x:Tb^(3+)-Yb^(3+) thin films were conducted by means of photoluminescence, Rutherford backscattering spectroscopy, Ellipsometry spectroscopy and Fourier transform infrared measurements. Their composition and refractive index was optimized to obtain good anti-reflection coating layer for c-Si solar cells.Transmission electron microscopy performs the uniform coatings on the textured emitter of c-Si solar cells. After the metallization process, we demonstrate monolithic c-Si solar cells with spectrum conversion layers, which lead to a relative increase by 1.34% in the conversion efficiency.展开更多
Light absorption enhancement is very important for improving the power conversion efficiency of a thin film a-Si solar cell. In this paper, a thin-film a-Si solar cell model with double-sided SiO2 particle layers is d...Light absorption enhancement is very important for improving the power conversion efficiency of a thin film a-Si solar cell. In this paper, a thin-film a-Si solar cell model with double-sided SiO2 particle layers is designed, and then the underlying mechanism of absorption enhancement is investigated by finite difference time domain（FDTD） simulation;finally the feasible experimental scheme for preparing the SiO2 particle layer is discussed. It is found that the top and bottom SiO2 particle layers play an important role in anti-reflection and light trapping, respectively. The light absorption of the cell with double-sided SiO2 layers greatly increases in a wavelength range of 300 nm-800 nm, and the ultimate efficiency increases more than 22% compared with that of the flat device. The cell model with double-sided SiO2 particle layers reported here can be used in varieties of thin film solar cells to further improve their performances.展开更多
To research the influence of oxygen flow rate on the structural and optical properties of TiO2 thin film,TiO2 films on glass were deposited by reactive magnetron sputtering.The microstructure and optical properties we...To research the influence of oxygen flow rate on the structural and optical properties of TiO2 thin film,TiO2 films on glass were deposited by reactive magnetron sputtering.The microstructure and optical properties were measured by X-ray diffractometry,AFM and UV-VIS transmittance spectroscopy,respectively.The results show that the films deposited at oxygen flow rate of 10 mL/min has the lowest roughness and the highest transmittance.The absorption angle shifts to longer wavelengths as oxygen flow rates increase from 5 to 10 mL/min,then to shorter ones as the oxygen flow rate increase from 10 to 30 mL/min.The band gap is 3.38 eV,which is nearly constant in the experiment.For the TiO2 thin films deposited at 10 mL/min of oxyge flow rate,there are nano-crystalline structures,which are suitable for anti-reflection(AR) coating in the solar cells structure system.展开更多
The highly inefficient simultaneous extraction of coal and gas from low-permeability and high-gas coal seams in deep mines is a major problem often restricting the sustainable development of coal industry.A possible w...The highly inefficient simultaneous extraction of coal and gas from low-permeability and high-gas coal seams in deep mines is a major problem often restricting the sustainable development of coal industry.A possible way to solve this problem under deep and complex geological conditions is represented by the technology based on the phase-change induced explosion of liquid carbon dioxide.In this work,the mechanism of formation of the coal mass fracture circle resulting from the gas cracking process is theoretically analyzed.Numerical simulations show that a blasting crushing zone with a radius of 1.0 m is formed around the blasting hole.The radius of the sec-ondary expansion zone caused by the exploding gas is 2.0 m,and the extension limit of the explosion fracture is 2.3 m.The gas phase change explosion is influenced by the coal roadway driving face,the gas content index and the analytical index of coal shavings.Experiments conducted for comparison also lead to the conclusion that the initial gas emission is increased by 3.7 times from the 100-meter borehole in the original coal mass after coalbed gas explosion anti-reflection.展开更多
In this paper we report on a high-contrast top-emitting organic light-emitting device utilizing a moderate-reflection contrast-enhancement stack and a high refractive index anti-reflection layer.The contrast-enhanceme...In this paper we report on a high-contrast top-emitting organic light-emitting device utilizing a moderate-reflection contrast-enhancement stack and a high refractive index anti-reflection layer.The contrast-enhancement stack consists of a thin metal anode layer,a dielectric bilayer,and a thick metal underlayer.The resulting device,with the optimized contrast-enhancement stack thicknesses of Ni（30 nm）/MgF 2（62 nm）/ZnS（16 nm）/Ni（20 nm） and the 25-nm-thick ZnS anti-reflection layer,achieves a luminous reflectance of 4.01% in the visible region and a maximum current efficiency of 0.99 cd/A（at 62.3 mA/cm 2） together with a very stable chromaticity.The contrast ratio reaches 561：1 at an on-state brightness of 1000 cd/m^2 under an ambient illumination of 140 lx.In addition,the anti-reflection layer can also enhance the transmissivity of the cathode and improve light out-coupling by the effective restraint of microcavity effects.展开更多
MACE (Metal-Assisted Chemical Etching) approach has drawn a lot of attentions due to its ability to create highly light-absorptive silicon surface. This method can generate numerous cylindrical shape microstructure on...MACE (Metal-Assisted Chemical Etching) approach has drawn a lot of attentions due to its ability to create highly light-absorptive silicon surface. This method can generate numerous cylindrical shape microstructure on the surface of silicon like a forest, which is called “silicon nanowires arrays”. This structure can dramatically suppress both reflection and transmission at the wavelength range from 400 nm to near-infrared 1800 nm by increasing the propagation path of light. In this paper, ordered silicon nanowires arrays with a large area are prepared by wet chemical etching. It is demonstrated that the SiNWs (Silicon nanowires) arrays with different morphologies can be fabricated from monocrystalline silicon of a given orientation by changing silver-plating time. Excellent anti-reflection performance in broadband wavelengths and incident angle is obtained. The fabrication method and potential application of such SiNWs in the field of photoelectric detection have great value and can provide reference for further research in this field.展开更多
Opening the silicon oxide mask of a capacitor in dynamic random access memory is a critical process on a capacitive coupled plasma(CCP)etch tool.Three steps,dielectric anti-reflective coating(DARC)etch back,silicon ox...Opening the silicon oxide mask of a capacitor in dynamic random access memory is a critical process on a capacitive coupled plasma(CCP)etch tool.Three steps,dielectric anti-reflective coating(DARC)etch back,silicon oxide etch and strip,are contained.To acquire good performance,such as low leakage current and high capacitance,for further fabricating capacitors,we should firstly optimize DARC etch back.We developed some experiments,focusing on etch time and chemistry,to evalu-ate the profile of a silicon oxide mask,DARC remain and critical dimension.The result shows that etch back time should be con-trolled in the range from 50 to 60 s,based on the current equipment and condition.It will make B/T ratio higher than 70%mean-while resolve the DARC remain issue.We also found that CH_(2)F_(2) flow should be~15 sccm to avoid reversed CD trend and keep in-line CD.展开更多
Dy2O3 is a rare earth oxide having a number of advanced applications in various fields including protective or antireflective coatings,Main objective of this novel research work is to check the effect of Cr and Cu add...Dy2O3 is a rare earth oxide having a number of advanced applications in various fields including protective or antireflective coatings,Main objective of this novel research work is to check the effect of Cr and Cu addition on different properties of Dy2O3 and achievement of antireflective thin films with enhanced abso rption.Thin films of these materials we re deposited using DC magnetron with reactive cosputtering.XRD studies reveals the crystalline nature of thin films having Dy2O3(222)reflection in all samples with Cr2O3(116)and CuO(111)reflections in Cr and Cu containing compositions.Field emission scanning electron microscopy demonstrates the homogeneous deposition of thin films with uniform shape,size and distribution of grains.Refractive index,extinction coefficient and absorption coefficient significantly increase while optical reflectance decreases with Cr and Cu mediation corroborating an improved antireflective mechanism.The imaginary part of dielectric constant is found to increase slightly with low tangent loss for Cr containing composition co nsidered favorable for energy storage applications.展开更多
Radio-frequency(RF)process products suffer from a wafer edge low yield issue,which is induced by contact opening.A failure mechanism has been proposed that is based on the characteristics of a wafer edge film stack.Th...Radio-frequency(RF)process products suffer from a wafer edge low yield issue,which is induced by contact opening.A failure mechanism has been proposed that is based on the characteristics of a wafer edge film stack.The large step height at the wafer's edge leads to worse planarization for the sparse poly-pattern region during the inter-layer dielectric(ILD)chemical mechanical polishing(CMP)process.A thicker bottom anti-reflect coating(BARC)layer was introduced for a sparse poly-pattern at the wafer edge region.The contact open issue was solved by increasing the break through(BT)time to get a large enough window.Well profile and resistance uniformity were obtained by contact etch recipe optimization.展开更多
Ge_(2)Sb_(2)Se_(4)Te_(1),a newly developed phase change material derived from Ge_(2)Sb_(2)Te_(5),has garnered significant interest among researchers due to its numerous advantages.Here,its phase change characteristics...Ge_(2)Sb_(2)Se_(4)Te_(1),a newly developed phase change material derived from Ge_(2)Sb_(2)Te_(5),has garnered significant interest among researchers due to its numerous advantages.Here,its phase change characteristics under the electron beam evaporation method are thoroughly investigated,and a layered tunable color structure is proposed.Based on the low intrinsic absorption of Ge_(2)Sb_(2)Se_(4)Te_(1) material,it exhibits excellent dynamic tunability along with vivid color appearance including high brightness and high purity.In experiments,five representative colors—red,green,blue,yellow,and purple—were successfully prepared.The peak reflection of these samples averaged 92%,and when heated to 320°C,the temperature at which the phase transition of Ge_(2)Sb_(2)Se_(4)Te_(1) occurred,reflection loss was barely observed.In addition,after phase transition,the sideband reflection at non-target wavelengths decreased by 30%,bringing high-purity crystalline-state colors and noticeable color changes.Therefore,it is believed that the structural color scheme proposed here will contribute to the development of many fields including smart glasses,artificial retinal devices,high-resolution displays,and beyond.展开更多
基金Supported by the Qing Lan Project of the Higher Education Institutions of Jiangsu Province,Qing Lan Project of Yangzhou Polytechnic Institute,the Natural Science Foundation of Yangzhou City under Grant No YZ2016123the National Natural Science Foundation of China under Grant No 61376004
文摘CdTe/CdS quantum dots（QDs） are fabricated on Si nanowires（NWs） substrates with and without Au nanoparticles（NPs）. The formation of Au NPs on Si NWs can be certified as shown in scanning electron microscopy images. The optical properties of samples are also investigated. It is interesting to find that the photoluminescence（PL） intensity of Cd Te/Cd S QD films on Si nanowire substrates with Au NPs is significantly increased,which can reach 8-fold higher than that of samples on planar Si without Au NPs. The results of finite-difference time-domain simulation indicate that Au NPs induce stronger localization of electric field and then boost the PL intensity of QDs nearby. Furthermore, the time-resolved luminescence decay curve shows the PL lifetime, which is about 5.5 ns at the emission peaks of QD films on planar, increasing from 1.8 ns of QD films on Si NWs to4.7 ns after introducing Au NPs into Si NWs.
文摘Structure and properties of anti-reflection thin films of spherical silicon solar cells were investigated and discussed. Conversion efficiencies of spherical Si solar cells coated with F-doped SnO2 anti-reflection films were improved by annealing. Optical absorption and fluorescence of the solar cells increased after annealing. Lattice constants of F-doped SnO2 anti-reflection layers, which were investigated by X-ray diffraction, decreased after annealing. A mechanism of atomic diffusion of F in SnO2 was discussed. The present work indicated a guideline for spherical silicon solar cells with higher efficiencies.
基金supported by the National Natural Science Foundation of China(Nos.62104028 and 62174021)the Creative Research Groups of the National Natural Science Foundation of Sichuan Province(No.2023NSFSC1973)+2 种基金the Natural Science Foundation of Sichuan Province(No.2022NSFSC0899)the Guang Dong Basic and Applied Basic Research Foundation(No.2023A1515110067)the China Postdoctoral Science Foundation(No.2021M700689).
文摘Perovskite solar cells have shown great potential in the field of underwater solar cells due to their excellent optoelectronic properties;however,their underwater performance and stability still hinder their practical use.In this research,a 1H,1H,2H,2H-heptadecafluorodecyl acrylate(HFDA)anti-reflection coating(ARC)was introduced as a high-transparent material for encapsulating perovskite solar modules(PSMs).Optical characterization results revealed that HFDA can effectively reduce reflection of light below 800 nm,aiding in the absorption of light within this wavelength range by underwater solar cells.Thus,a remarkable efficiency of 14.65%was achieved even at a water depth of 50 cm.And,the concentration of Pb^(2+)for HFDA-encapsulated film is significantly reduced from 186 to 16.5 ppb after being immersed in water for 347 h.Interestingly,the encapsulated PSMs still remained above 80%of their initial efficiency after continuous underwater illumination for 400 h.Furthermore,being exposed to air,the encapsulated PSMs maintained 94%of their original efficiency after 1000 h light illumination.This highly transparent ARC shows great potentials in enhancing the stability of perovskite devices,applicable not only to underwater cells but also extendable to land-based photovoltaic devices.
基金supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(2020R1I1A3054824)supported by the Nano&Material Technology Development Program(RS-2023-00282896)through the National Research Foundation of Korea(NRF)funded by Ministry of Science and ICT。
文摘Perovskite solar cells(PSCs)have been receiving attention for photovoltaic advantages of high-power conversion efficiency,cost-effectiveness,and easy fabrication process.Particularly,flexible PSCs(FPSCs)are considered to be promising renewable power sources due to the positive potential of flexible and lightweight properties.However,FPSCs tend to have lower efficiency compared to glass-based rigid PSCs(RPSCs).The main issue is high refractive index of polymer substrates such as polyethylene naphthalate(PEN),used for FPSCs,thereby reducing the external light absorption efficiency.In this study,we developed glasswing inspired sticker-type multilayer anti-reflective(GSMA)film derived from the wings of the glasswing butterfly to enhance the light absorption efficiency of FPSCs.We designed and fabricated the GSMA film with multilayers specifically for FPSCs.The suitable materials and nanostructures to adjust the refractive index are theoretically optimized.The GSMA film effectively improved the optical properties of PSC substrates,reducing reflectance(∼5.01%)and enhancing light transmittance(∼6.17%)in indium tin oxide(ITO)/PEN.In addition,the GSMA film on PEN maintains more than 94.70%of its initial transmittance even after being exposed to various harsh environments for 500 h,and GSMA film demonstrates flexibility by maintaining its initial structure even after a bending test(bending radius of 1 mm).The FPSCs and RPSCs assisted by GSMA film show high short-circuit current density(FPSC:∼25.28 mA/cm^(2),up to 26.05 mA/cm^(2),RPSC:∼24.27 mA/cm^(2))and power conversion efficiency(FPSC:∼22.72%,RPSC:∼22.31%),significantly narrowing the efficiency gap between FPSC and RPSCs.
基金financially supported by the National Natural Science Foundation of China(61474128,21503261,61504155and 61404145)Youth Innovation Fund for Interdisciplinary Research of SARI(Y526453233,141004)+2 种基金Science & Technology Commission of Shanghai Municipality(14JC1492900,14511102302,15DZ1100502)Youth Innovation Promotion Association,CAS(2013302)Development Fund for Information communication and integrated circuit technology public service platform(No.2016-14)supported by Zhangjiang Adminstrative Committee
文摘Complementary metal oxide semiconductor(CMOS) image sensors(CIS) are being widely used in digital video cameras, web cameras, digital single lens reflex camera(DSLR), smart phones and so on, owing to their high level of integration, random accessibility, and low-power operation. It needs to be installed with the cover glass in practical applications to protect the sensor from damage, mechanical issues,and environmental conditions, which, however, limits the accuracy and usability of the sensor due to the reflection in the optical path from air-to-cover glass-to-air. In this work, the flexible 3D nanocone anti-reflection(AR) film with controlled aspect ratio was firstly employed to reduce the light reflection at air/cover glass/air interfaces by directly attaching onto the front and rear sides of the CIS cover glass.As both the front and rear sides of cover glass were coated by the AR film, the output image quality was found to be improved with external quantum efficiency increased by 7%, compared with that without AR film. The mean digital data value, root-mean-square contrast, and dynamic range are increased by45.14%, 38.61% and 57, respectively, for the output image with AR films. These results provide a novel and facile pathway to improve the CIS performance and also could be extended to rational design of other image sensors and optoelectronic devices.
基金supported by the doctoral program foundation of Beijing(20120018110003)
文摘An ultra-thin and broadband absorber which consists of periodic rings with gaps is proposed in this paper. The periodic rings are printed on the middle metallic layers in a four-layer substrate of total thickness is only 3.4 mm. Simulation results, which are gotten by using finite element method(FEM) and finite-difference time-domain(FDTD), show that the absorption is higher than 90% cover the frequencies range from 7.8 GHz to 22.2 GHz. The measurement results of the absorption agree with simulated ones very well. We also discuss the working mechanism according to the anti-reflection theory in the paper.
文摘Undesired reflection caused by impedance mismatch can lead to significant power loss and other unwanted effects. In the terahertz regime, anti-reflection method has evolved from simple quarter-wave antireflection coating to sophisticated metamaterial device and photonic structures. In this paper, we examined and compared the theories and techniques of several antireflection implementations for terahertz waves, with emphasis on gradient index photonic structures. A comprehensive study is presented on the design, fabrication and evaluation of this new approach.
文摘Broadband transparent films play a pivotal role in various applications such as lenses and solar cells,particularly porous structured transparent films exhibit significant potential.This study investigates a porous SiO_(2) refractive index gradient anti-reflective film prepared by atomic layer deposition(ALD).A porous SiO_(2) film with gradual porosity was obtained by phosphoric acid etching of Al_(2)O_(3)/SiO_(2) multilayers with gradient Al2O3 ratios,achieving a gradual decrease in refractive index from the substrate to the surface.The film exhibited an average transmittance as high as 97.8%within the wavelength range from 320 nm to 1200 nm.The environmental adaptability was further enhanced by surface modification using rare earth oxide(REO)La_(2)O_(3),resulting in formation of a lotus leaf-like structure and achieving a water contact angle of 100.0°.These data proved that the modification significantly improved hydrophobic self-cleaning capability while maintaining exceptional transparency of the film.The surface structure of the modified film remained undamaged even after undergoing wipe testing,demonstrating its excellent surface durability.
基金the National Natural Science Foundation of China(No:69978017,20133040)Shanghai Key Subject Programme,Chinese Foundation of High Technology(2002AA842052)Shanghai Natural Science Foundation(02ZE14101)as well as Shanghai Nanotechnology Promotion Center(0159um039).
文摘Structural strengthening of the nano porous silica films has been reported. The films were prepared with a base/acid two-step catalyzed TEOS-based sol-gel processing and dip-coating, and then baked in the mixed gas of ammonia and water vapor. The silica films were characterized with TEM, AFM, FTIR, spectrophotometer, ellipsometer, and abrasion test, respectively. The experimental results have shown that the films have a nanostructure with a low refractive index and can form an excellent scratch-resistant broadband anti-reflectance. The two-step catalysis noticeably strengthens the films, and the mixed gas treatment further improves mechanical strength of the silica network. Finally the strengthening mechanism has been discussed.
基金The authors gratefully acknowledge the financial support of the Brazilian research funding agency CNPq and the Coordination for the Improvement of Higher Education Personnel(CAPES)
文摘Anti-reflective (AR) single layer of silica-titania (SiO2-TiO2) coatings were obtained from sols containing pyromellitic dianhydride (PMDA) derivatives and Ti and Si precursors on glass substrate by dip-coating method. The coatings showed very high optical quality and the transmission was improved to up to 98.5%. Furthermore, the coatings also presented good mechanical stability.
基金Project supported by Ministry of Science and Technology,Taiwan(MOST 105-2911-I-259-501)the French Agence Nationale de Recherche through the GENESE Project(ANR-13-BSS09-0020-01)the French Ministry of Research through the ORCHID Project(33572XF)
文摘In this study, we propose the fabrication of monolithic crystalline silicon solar cells with Tb^(3+) and Yb^(3+)-doped silicon nitride(SiN_x) layers by low-cost screen-printing methods. The performances of c-Si solar cells can be enhanced by rare-earth ions doped SiN_x layers via the mechanism of spectrum conversion.These SiN_x doped and codoped thin films were deposited by reactive magnetron co-sputtering and integrated as the antireflection coating layers in c-Si solar cells. The characterizations of SiN_x, SiN_x:Tb^(3+) tand SiN_x:Tb^(3+)-Yb^(3+) thin films were conducted by means of photoluminescence, Rutherford backscattering spectroscopy, Ellipsometry spectroscopy and Fourier transform infrared measurements. Their composition and refractive index was optimized to obtain good anti-reflection coating layer for c-Si solar cells.Transmission electron microscopy performs the uniform coatings on the textured emitter of c-Si solar cells. After the metallization process, we demonstrate monolithic c-Si solar cells with spectrum conversion layers, which lead to a relative increase by 1.34% in the conversion efficiency.
基金Project supported by the National High-Tech Research and Development Program of China(Grant No.2011AA050518)the University Research Program of Guangxi Education Department,China(Grant No.LX2014288)the Natural Science Foundation of Guangxi Zhuang Autonomous Region,China(Grant No.2013GXNSBA019014)
文摘Light absorption enhancement is very important for improving the power conversion efficiency of a thin film a-Si solar cell. In this paper, a thin-film a-Si solar cell model with double-sided SiO2 particle layers is designed, and then the underlying mechanism of absorption enhancement is investigated by finite difference time domain（FDTD） simulation;finally the feasible experimental scheme for preparing the SiO2 particle layer is discussed. It is found that the top and bottom SiO2 particle layers play an important role in anti-reflection and light trapping, respectively. The light absorption of the cell with double-sided SiO2 layers greatly increases in a wavelength range of 300 nm-800 nm, and the ultimate efficiency increases more than 22% compared with that of the flat device. The cell model with double-sided SiO2 particle layers reported here can be used in varieties of thin film solar cells to further improve their performances.
基金Project(08FJ1002) supported by the Hunan Province Key Project of Science and Technology,China
文摘To research the influence of oxygen flow rate on the structural and optical properties of TiO2 thin film,TiO2 films on glass were deposited by reactive magnetron sputtering.The microstructure and optical properties were measured by X-ray diffractometry,AFM and UV-VIS transmittance spectroscopy,respectively.The results show that the films deposited at oxygen flow rate of 10 mL/min has the lowest roughness and the highest transmittance.The absorption angle shifts to longer wavelengths as oxygen flow rates increase from 5 to 10 mL/min,then to shorter ones as the oxygen flow rate increase from 10 to 30 mL/min.The band gap is 3.38 eV,which is nearly constant in the experiment.For the TiO2 thin films deposited at 10 mL/min of oxyge flow rate,there are nano-crystalline structures,which are suitable for anti-reflection(AR) coating in the solar cells structure system.
基金supported by the National Science and Technology Major Project(Grant No.2016ZX05067004-003).
文摘The highly inefficient simultaneous extraction of coal and gas from low-permeability and high-gas coal seams in deep mines is a major problem often restricting the sustainable development of coal industry.A possible way to solve this problem under deep and complex geological conditions is represented by the technology based on the phase-change induced explosion of liquid carbon dioxide.In this work,the mechanism of formation of the coal mass fracture circle resulting from the gas cracking process is theoretically analyzed.Numerical simulations show that a blasting crushing zone with a radius of 1.0 m is formed around the blasting hole.The radius of the sec-ondary expansion zone caused by the exploding gas is 2.0 m,and the extension limit of the explosion fracture is 2.3 m.The gas phase change explosion is influenced by the coal roadway driving face,the gas content index and the analytical index of coal shavings.Experiments conducted for comparison also lead to the conclusion that the initial gas emission is increased by 3.7 times from the 100-meter borehole in the original coal mass after coalbed gas explosion anti-reflection.
基金Project supported by the State Key Development Program for Basic Research of China (Grant No. 2009CB930600)the National Natural Science Foundation of China (Grant Nos. 60907047,61274065,60977024,21101095,20974046,21003076,51173081,and 61136003)+3 种基金the Specialized Research Foundation for the Doctoral Program of Higher Education,China (Grant No. 20093223120003)the Natural Science Foundation of Institutions of Higher Education of Jiangsu Province,China (Grant Nos. SJ209003,09KJB150009,10KJB510013,and TJ209035)the "Qing Lan" Program of Jiangsu Province,Chinathe Program of Nanjing University of Posts and Telecommunications,China (Grant Nos. NY210015,NY211069,and NY210040)
文摘In this paper we report on a high-contrast top-emitting organic light-emitting device utilizing a moderate-reflection contrast-enhancement stack and a high refractive index anti-reflection layer.The contrast-enhancement stack consists of a thin metal anode layer,a dielectric bilayer,and a thick metal underlayer.The resulting device,with the optimized contrast-enhancement stack thicknesses of Ni（30 nm）/MgF 2（62 nm）/ZnS（16 nm）/Ni（20 nm） and the 25-nm-thick ZnS anti-reflection layer,achieves a luminous reflectance of 4.01% in the visible region and a maximum current efficiency of 0.99 cd/A（at 62.3 mA/cm 2） together with a very stable chromaticity.The contrast ratio reaches 561：1 at an on-state brightness of 1000 cd/m^2 under an ambient illumination of 140 lx.In addition,the anti-reflection layer can also enhance the transmissivity of the cathode and improve light out-coupling by the effective restraint of microcavity effects.
文摘MACE (Metal-Assisted Chemical Etching) approach has drawn a lot of attentions due to its ability to create highly light-absorptive silicon surface. This method can generate numerous cylindrical shape microstructure on the surface of silicon like a forest, which is called “silicon nanowires arrays”. This structure can dramatically suppress both reflection and transmission at the wavelength range from 400 nm to near-infrared 1800 nm by increasing the propagation path of light. In this paper, ordered silicon nanowires arrays with a large area are prepared by wet chemical etching. It is demonstrated that the SiNWs (Silicon nanowires) arrays with different morphologies can be fabricated from monocrystalline silicon of a given orientation by changing silver-plating time. Excellent anti-reflection performance in broadband wavelengths and incident angle is obtained. The fabrication method and potential application of such SiNWs in the field of photoelectric detection have great value and can provide reference for further research in this field.
文摘Opening the silicon oxide mask of a capacitor in dynamic random access memory is a critical process on a capacitive coupled plasma(CCP)etch tool.Three steps,dielectric anti-reflective coating(DARC)etch back,silicon oxide etch and strip,are contained.To acquire good performance,such as low leakage current and high capacitance,for further fabricating capacitors,we should firstly optimize DARC etch back.We developed some experiments,focusing on etch time and chemistry,to evalu-ate the profile of a silicon oxide mask,DARC remain and critical dimension.The result shows that etch back time should be con-trolled in the range from 50 to 60 s,based on the current equipment and condition.It will make B/T ratio higher than 70%mean-while resolve the DARC remain issue.We also found that CH_(2)F_(2) flow should be~15 sccm to avoid reversed CD trend and keep in-line CD.
基金the Deanship of Scientific Research at King Saud University for funding under Research Group(No.RG 1435-004)
文摘Dy2O3 is a rare earth oxide having a number of advanced applications in various fields including protective or antireflective coatings,Main objective of this novel research work is to check the effect of Cr and Cu addition on different properties of Dy2O3 and achievement of antireflective thin films with enhanced abso rption.Thin films of these materials we re deposited using DC magnetron with reactive cosputtering.XRD studies reveals the crystalline nature of thin films having Dy2O3(222)reflection in all samples with Cr2O3(116)and CuO(111)reflections in Cr and Cu containing compositions.Field emission scanning electron microscopy demonstrates the homogeneous deposition of thin films with uniform shape,size and distribution of grains.Refractive index,extinction coefficient and absorption coefficient significantly increase while optical reflectance decreases with Cr and Cu mediation corroborating an improved antireflective mechanism.The imaginary part of dielectric constant is found to increase slightly with low tangent loss for Cr containing composition co nsidered favorable for energy storage applications.
基金supported by Shanghai Rising-Star Program (B type) (No. 18QB1401900)
文摘Radio-frequency(RF)process products suffer from a wafer edge low yield issue,which is induced by contact opening.A failure mechanism has been proposed that is based on the characteristics of a wafer edge film stack.The large step height at the wafer's edge leads to worse planarization for the sparse poly-pattern region during the inter-layer dielectric(ILD)chemical mechanical polishing(CMP)process.A thicker bottom anti-reflect coating(BARC)layer was introduced for a sparse poly-pattern at the wafer edge region.The contact open issue was solved by increasing the break through(BT)time to get a large enough window.Well profile and resistance uniformity were obtained by contact etch recipe optimization.
基金supported by the National Key Research and Development Program of China(No.2020YFC2200403)the National Natural Science Foundation of China(No.62375231)the Fujian Province Science and Technology Planning Project(No.2022H6015).
文摘Ge_(2)Sb_(2)Se_(4)Te_(1),a newly developed phase change material derived from Ge_(2)Sb_(2)Te_(5),has garnered significant interest among researchers due to its numerous advantages.Here,its phase change characteristics under the electron beam evaporation method are thoroughly investigated,and a layered tunable color structure is proposed.Based on the low intrinsic absorption of Ge_(2)Sb_(2)Se_(4)Te_(1) material,it exhibits excellent dynamic tunability along with vivid color appearance including high brightness and high purity.In experiments,five representative colors—red,green,blue,yellow,and purple—were successfully prepared.The peak reflection of these samples averaged 92%,and when heated to 320°C,the temperature at which the phase transition of Ge_(2)Sb_(2)Se_(4)Te_(1) occurred,reflection loss was barely observed.In addition,after phase transition,the sideband reflection at non-target wavelengths decreased by 30%,bringing high-purity crystalline-state colors and noticeable color changes.Therefore,it is believed that the structural color scheme proposed here will contribute to the development of many fields including smart glasses,artificial retinal devices,high-resolution displays,and beyond.
