The development of InGaAs/InP single-photon avalanche photodiodes(SPADs)necessitates the utiliza-tion of a two-element diffusion technique to achieve accurate manipulation of the multiplication width and the dis-tribu...The development of InGaAs/InP single-photon avalanche photodiodes(SPADs)necessitates the utiliza-tion of a two-element diffusion technique to achieve accurate manipulation of the multiplication width and the dis-tribution of its electric field.Regarding the issue of accurately predicting the depth of diffusion in InGaAs/InP SPAD,simulation analysis and device development were carried out,focusing on the dual diffusion behavior of zinc atoms.A formula of X_(j)=k√t-t_(0)+c to quantitatively predict the diffusion depth is obtained by fitting the simulated twice-diffusion depths based on a two-dimensional(2D)model.The 2D impurity morphologies and the one-dimensional impurity profiles for the dual-diffused region are characterized by using scanning electron micros-copy and secondary ion mass spectrometry as a function of the diffusion depth,respectively.InGaAs/InP SPAD devices with different dual-diffusion conditions are also fabricated,which show breakdown behaviors well consis-tent with the simulated results under the same junction geometries.The dark count rate(DCR)of the device de-creased as the multiplication width increased,as indicated by the results.DCRs of 2×10^(6),1×10^(5),4×10^(4),and 2×10^(4) were achieved at temperatures of 300 K,273 K,263 K,and 253 K,respectively,with a bias voltage of 3 V,when the multiplication width was 1.5µm.These results demonstrate an effective prediction route for accu-rately controlling the dual-diffused zinc junction geometry in InP-based planar device processing.展开更多
One new Zn（Ⅱ） complex [Zn2（cptpy）2（tzba）（H2O）]·H2O（1, Hcptpy = 4-（4-carboxyphenyl）-2,2＇：4＇,4＇＇-terpyridine（Hcptpy）, H_2tzba = 4-（tetrazol-5-yl）benzenecarboxylic acid） has been synthesized an...One new Zn（Ⅱ） complex [Zn2（cptpy）2（tzba）（H2O）]·H2O（1, Hcptpy = 4-（4-carboxyphenyl）-2,2＇：4＇,4＇＇-terpyridine（Hcptpy）, H_2tzba = 4-（tetrazol-5-yl）benzenecarboxylic acid） has been synthesized and characterized by elemental analysis and single-crystal X-ray diffraction techniques. It is formulated as C52H36O8N10Zn2, crystallizes in monoclinic system, space group P21/c with α = 15.1599（13）, b = 28.083（2）, c = 10.9039（9） A, b = 97.517（8）o. V = 4602.3（6） A^3, Z = 4, Mr = 1059.68, Dc = 1.529 g/cm^3, F（000） = 2168 and μ = 1.112 mm^-1. The final R = 0.0831 and wR = 0.2143 for 8458 observed reflections with I 〉 2s（I）. The assembly of polyfunctional organic ligands Hcptpy and H_2tzba with Zn（II） atoms resulting in a rare example of double-edge ladders, which is further extended into a 3D supramolecular network via O–H…O/N hydrogen bonds. In addition, thermal gravimetric analysis（TGA） and PXRD patterns for 1 were studied. Photo luminescent property of 1 was also investigated.展开更多
A convenient and environmentally benign procedure for the synthesis of glycals from glycosyl bromides with very low zinc dust loading （1.5 equiv.） is described. The process is activated by β-cyclodextrin and ultras...A convenient and environmentally benign procedure for the synthesis of glycals from glycosyl bromides with very low zinc dust loading （1.5 equiv.） is described. The process is activated by β-cyclodextrin and ultrasound. Based on 19 samples, this method has been demonstrated to be highly effective for a broad range of glycosyl bromides, including acidor base-sensitive and disaccharide glycosyl bromides. A yield of 85%--96% of glycals was obtained.展开更多
A new Zn2＋ probe L2-Zn（L2=naphthofuran carbonylhydrazone derivant） was synthesized as a fluores- cence chemosensor for Cu2＋, by which Cuz＋ ion could be detected with high selectivity and sensitivity in a wide pH ...A new Zn2＋ probe L2-Zn（L2=naphthofuran carbonylhydrazone derivant） was synthesized as a fluores- cence chemosensor for Cu2＋, by which Cuz＋ ion could be detected with high selectivity and sensitivity in a wide pH range via a displacement ＂turn-off＂ signaling strategy. Whereas the coordination between Zn2＋ and L2 resulted in a considerable enhancement of typical luminescence of a naphthalofuran group in complex L2-Zn, the addition of Cu2＋ ion led to a dramatic decrease in the emission intensity of probe L2-Zn at about 503 nm（excitation at 423 nm）. The competitive fluorescent experiments showed that other metal ions, such as Hgz＋, Fe3＋, Ag＋, Ca2＋, Co2＋, Ni2＋, Cd2＋, Pb2＋, Zn2＋, Cr3＋ and Mg2＋ could not impact tile detection of Cu2＋. The detection limit of the novel probe L2-Zn for Cu2~ ion was as low as 2.3× 10 7 mol/L, which is far lower than the guideline value of 1.6× 10-5 mol/L of the United States Environmental Protection Agency.展开更多
基金Supported by Shanghai Natural Science Foundation(22ZR1472600).
文摘The development of InGaAs/InP single-photon avalanche photodiodes(SPADs)necessitates the utiliza-tion of a two-element diffusion technique to achieve accurate manipulation of the multiplication width and the dis-tribution of its electric field.Regarding the issue of accurately predicting the depth of diffusion in InGaAs/InP SPAD,simulation analysis and device development were carried out,focusing on the dual diffusion behavior of zinc atoms.A formula of X_(j)=k√t-t_(0)+c to quantitatively predict the diffusion depth is obtained by fitting the simulated twice-diffusion depths based on a two-dimensional(2D)model.The 2D impurity morphologies and the one-dimensional impurity profiles for the dual-diffused region are characterized by using scanning electron micros-copy and secondary ion mass spectrometry as a function of the diffusion depth,respectively.InGaAs/InP SPAD devices with different dual-diffusion conditions are also fabricated,which show breakdown behaviors well consis-tent with the simulated results under the same junction geometries.The dark count rate(DCR)of the device de-creased as the multiplication width increased,as indicated by the results.DCRs of 2×10^(6),1×10^(5),4×10^(4),and 2×10^(4) were achieved at temperatures of 300 K,273 K,263 K,and 253 K,respectively,with a bias voltage of 3 V,when the multiplication width was 1.5µm.These results demonstrate an effective prediction route for accu-rately controlling the dual-diffused zinc junction geometry in InP-based planar device processing.
基金supported by the National Natural Science Foundation of China(Nos.21273101 and 21302082)Foundation for Science&Technology Innovation Talents in Henan province(Nos.2014HASTIT014 and 164100510012)+1 种基金Tackle Key Problem of Science and Technology Project of Henan Province,(No.14210 231 0483)Ministry of Science and Technology of China(973 Project,No.2014CB660804)
文摘One new Zn（Ⅱ） complex [Zn2（cptpy）2（tzba）（H2O）]·H2O（1, Hcptpy = 4-（4-carboxyphenyl）-2,2＇：4＇,4＇＇-terpyridine（Hcptpy）, H_2tzba = 4-（tetrazol-5-yl）benzenecarboxylic acid） has been synthesized and characterized by elemental analysis and single-crystal X-ray diffraction techniques. It is formulated as C52H36O8N10Zn2, crystallizes in monoclinic system, space group P21/c with α = 15.1599（13）, b = 28.083（2）, c = 10.9039（9） A, b = 97.517（8）o. V = 4602.3（6） A^3, Z = 4, Mr = 1059.68, Dc = 1.529 g/cm^3, F（000） = 2168 and μ = 1.112 mm^-1. The final R = 0.0831 and wR = 0.2143 for 8458 observed reflections with I 〉 2s（I）. The assembly of polyfunctional organic ligands Hcptpy and H_2tzba with Zn（II） atoms resulting in a rare example of double-edge ladders, which is further extended into a 3D supramolecular network via O–H…O/N hydrogen bonds. In addition, thermal gravimetric analysis（TGA） and PXRD patterns for 1 were studied. Photo luminescent property of 1 was also investigated.
文摘A convenient and environmentally benign procedure for the synthesis of glycals from glycosyl bromides with very low zinc dust loading （1.5 equiv.） is described. The process is activated by β-cyclodextrin and ultrasound. Based on 19 samples, this method has been demonstrated to be highly effective for a broad range of glycosyl bromides, including acidor base-sensitive and disaccharide glycosyl bromides. A yield of 85%--96% of glycals was obtained.
基金the National Natural Science Foundation of China（Nos.21064006, 21262032, 21161018）.
文摘A new Zn2＋ probe L2-Zn（L2=naphthofuran carbonylhydrazone derivant） was synthesized as a fluores- cence chemosensor for Cu2＋, by which Cuz＋ ion could be detected with high selectivity and sensitivity in a wide pH range via a displacement ＂turn-off＂ signaling strategy. Whereas the coordination between Zn2＋ and L2 resulted in a considerable enhancement of typical luminescence of a naphthalofuran group in complex L2-Zn, the addition of Cu2＋ ion led to a dramatic decrease in the emission intensity of probe L2-Zn at about 503 nm（excitation at 423 nm）. The competitive fluorescent experiments showed that other metal ions, such as Hgz＋, Fe3＋, Ag＋, Ca2＋, Co2＋, Ni2＋, Cd2＋, Pb2＋, Zn2＋, Cr3＋ and Mg2＋ could not impact tile detection of Cu2＋. The detection limit of the novel probe L2-Zn for Cu2~ ion was as low as 2.3× 10 7 mol/L, which is far lower than the guideline value of 1.6× 10-5 mol/L of the United States Environmental Protection Agency.
