We report a theoretical study of a broadband Si/graded-SiGe/Ge/Ge0.9Sn0.1 p–i–n photodetector with a flat response based on modulating thickness of the layers in the active region.The responsivity of the photodetect...We report a theoretical study of a broadband Si/graded-SiGe/Ge/Ge0.9Sn0.1 p–i–n photodetector with a flat response based on modulating thickness of the layers in the active region.The responsivity of the photodetector is about 0.57 A/W in the range of 700 to 1800 nm.This structure is suitable for silicon-based epitaxial growth.Annealing is technically applied to form the graded-SiGe.The photodetector reaches a cut-off wavelength at^2300 nm and a low dark-current density under 3 V reverse bias about 0.17 mA/cm^2 is achieved theoretical at room temperature.This work is of great significance for silicon-based detection and communication,from visible to infrared.展开更多
Bacteria-caused wound infection greatly threatens human health,thus developing an efficient and safe antibacterial agent without drug resistance is still a great challenge.Herein,a confined vulcanization strategy is p...Bacteria-caused wound infection greatly threatens human health,thus developing an efficient and safe antibacterial agent without drug resistance is still a great challenge.Herein,a confined vulcanization strategy is proposed to construct copper sulfides-loaded dual-mesoporous silica nanospheres(Cux-Sy@DMSNs)with various crystal phases for reactive oxygen species(ROS)-mediated and photothermal antibacterial application.With the pore confinement of DMSNs,the crystal phases of copper sulfides including CuS,Cu_(9)S_(5)and Cui.96S can be easily controlled by changing the vulcanization temperature.The relationships between the crystal phases and photothermal properties as well as peroxidase-like activity of copper sulfides were systematically investigated.Results show that the obtained CuS@DMSNs exhibited higher photothermal ability with remarkable photothermal conversion efficiency of 36.86%in the second near-infrared region(NIR-II)and better peroxidase-like activity,compared to those of Cu_(9)S_(5)@DMSNs and Cu_(1.96)S@DMSNs.As a result,the in vitro experiments showed the good antibacterial effect against both gram-negative E.coli and gram-positive S.aureus under 1064 nm laser irradiation and the presence of H_(2)O_(2).Besides,the CCK-8 assay indicated that CuS@p-DMSNs have minimal cytotoxicity against normal human umbilical vein endothelial cells at the ranged concentrations.Therefore,the resultant CuS@p-DMSNs could act as a promising antibacterial agent for deep wound bacterial infection treatment.展开更多
An amorphous Ge(a-Ge) intermediate layer is introduced into the Si bonded interface to lower the annealing temperature and achieve good electrical characteristics. The interface and electrical characteristics of nSi...An amorphous Ge(a-Ge) intermediate layer is introduced into the Si bonded interface to lower the annealing temperature and achieve good electrical characteristics. The interface and electrical characteristics of nSi/n-Si and p-Si/n-Si junctions manufactured by low-temperature wafer bonding based on a thin amorphous Ge are investigated. It is found that the bubble density tremendously decreases when the a-Ge film is not immersed in DI water. This is due to the decrease of the –OH groups. In addition, when the samples are annealed at 400 °C for20 h, the bubbles totally disappear. This can be explained by the appearance of the polycrystalline Ge(absorption of H;) at the bonded interface. The junction resistance of the n-Si/n-Si bonded wafers decreases with the increase of the annealing temperature. This is consistent with the recrystallization of the a-Ge when high-temperature annealing is conducted. The carrier transport of the Si-based PN junction annealed at 350 °C is consistent with the trap-assisted tunneling model and that annealed at 400 °C is related to the carrier recombination model.展开更多
基金This work was supported by National Basic Research Program of China(No.2013CB632103)National Natural Science Foundation of China(Nos.61534005 and 61474081)Scientific Research Project of Fujian Provincial Department of Education(No.JA15651).
文摘We report a theoretical study of a broadband Si/graded-SiGe/Ge/Ge0.9Sn0.1 p–i–n photodetector with a flat response based on modulating thickness of the layers in the active region.The responsivity of the photodetector is about 0.57 A/W in the range of 700 to 1800 nm.This structure is suitable for silicon-based epitaxial growth.Annealing is technically applied to form the graded-SiGe.The photodetector reaches a cut-off wavelength at^2300 nm and a low dark-current density under 3 V reverse bias about 0.17 mA/cm^2 is achieved theoretical at room temperature.This work is of great significance for silicon-based detection and communication,from visible to infrared.
基金supported by the National Natural Science Foundation of China(grant No.52072124 and 51972112)Natural Science Foundation of Shanghai(grant No.20zR1414900)+1 种基金Program of Shanghai Academic/Technology Research Leader(grant No.22XD1421100)The Fundamental Research Funds for the Central Universities,and the 111 project(grant No.B14018).
文摘Bacteria-caused wound infection greatly threatens human health,thus developing an efficient and safe antibacterial agent without drug resistance is still a great challenge.Herein,a confined vulcanization strategy is proposed to construct copper sulfides-loaded dual-mesoporous silica nanospheres(Cux-Sy@DMSNs)with various crystal phases for reactive oxygen species(ROS)-mediated and photothermal antibacterial application.With the pore confinement of DMSNs,the crystal phases of copper sulfides including CuS,Cu_(9)S_(5)and Cui.96S can be easily controlled by changing the vulcanization temperature.The relationships between the crystal phases and photothermal properties as well as peroxidase-like activity of copper sulfides were systematically investigated.Results show that the obtained CuS@DMSNs exhibited higher photothermal ability with remarkable photothermal conversion efficiency of 36.86%in the second near-infrared region(NIR-II)and better peroxidase-like activity,compared to those of Cu_(9)S_(5)@DMSNs and Cu_(1.96)S@DMSNs.As a result,the in vitro experiments showed the good antibacterial effect against both gram-negative E.coli and gram-positive S.aureus under 1064 nm laser irradiation and the presence of H_(2)O_(2).Besides,the CCK-8 assay indicated that CuS@p-DMSNs have minimal cytotoxicity against normal human umbilical vein endothelial cells at the ranged concentrations.Therefore,the resultant CuS@p-DMSNs could act as a promising antibacterial agent for deep wound bacterial infection treatment.
基金Project supported by the National Natural Science Foundation of China(Nos.61534005,61474081)
文摘An amorphous Ge(a-Ge) intermediate layer is introduced into the Si bonded interface to lower the annealing temperature and achieve good electrical characteristics. The interface and electrical characteristics of nSi/n-Si and p-Si/n-Si junctions manufactured by low-temperature wafer bonding based on a thin amorphous Ge are investigated. It is found that the bubble density tremendously decreases when the a-Ge film is not immersed in DI water. This is due to the decrease of the –OH groups. In addition, when the samples are annealed at 400 °C for20 h, the bubbles totally disappear. This can be explained by the appearance of the polycrystalline Ge(absorption of H;) at the bonded interface. The junction resistance of the n-Si/n-Si bonded wafers decreases with the increase of the annealing temperature. This is consistent with the recrystallization of the a-Ge when high-temperature annealing is conducted. The carrier transport of the Si-based PN junction annealed at 350 °C is consistent with the trap-assisted tunneling model and that annealed at 400 °C is related to the carrier recombination model.