High-quality and high-resistivity GaN films were grown on (0001) sapphire face by metal-organic vapour phase epitaxy. To measure the surface acoustic wave properties accurately, we deposited metallized interdigital tr...High-quality and high-resistivity GaN films were grown on (0001) sapphire face by metal-organic vapour phase epitaxy. To measure the surface acoustic wave properties accurately, we deposited metallized interdigital trans ducers on the GaN surface. The acoustic surface wave velocity and electromechanical coupling coefficient were measured, respectively, to be 5667m/s and 1.9% by the pulse method.展开更多
Electrochemical capacitance-voltage profiling,Raman and absorption spectroscopy measurements are employed to characterize the electronic and optical properties of silicon supersaturated with sulfur above the equilibri...Electrochemical capacitance-voltage profiling,Raman and absorption spectroscopy measurements are employed to characterize the electronic and optical properties of silicon supersaturated with sulfur above the equilibrium solubility limit.Silicon wafers are ion implanted with 50keV 32S+ to a dose of 1 × 10^(16) ions/cm^(2) and subsequently irradiated by femtosecond pulses at a fluence of 0.2 J/cm^(2),followed by thermal annealing at 825K for 30min.The spectral response of the photodiode fabricated from the laser-irradiated sample is also investigated.It is found that femtosecond laser irradiation and subsequent thermal annealing can electrically and optically activate the supersaturated sulfur dopant in silicon,as well as reduce the implantation-induced damage in the silicon lattice.展开更多
Optical and electrical properties of single-crystal Si supersaturated with Se by ion implantation and followed by different thermal annealing conditions are reported.Si is implanted with 1×10^(16) cm^(-2) Se ions...Optical and electrical properties of single-crystal Si supersaturated with Se by ion implantation and followed by different thermal annealing conditions are reported.Si is implanted with 1×10^(16) cm^(-2) Se ions at 100 keV.The total substitutional fraction of Se atoms in Si is 45%under the annealing at 800℃ for 30 min and the peak concentration of substitutional Se atoms is exceeded 1×10^(20) cm^(-3).A temperature-independent carrier concentration of 3×10^(19) cm^(-3) is measured and the near-infrared absorption is closed to 30%.These results indicate the insulator-to-metal transition of the doped layer and the formation of impurity bands in the Si band gap.展开更多
To transfer a photon with a 1.55μm wavelength into an electron in an integrated optoelectronic silicon waveguide detector,selenium-doped silicon with deep energy levels is used.The deep levels in the silicon with imp...To transfer a photon with a 1.55μm wavelength into an electron in an integrated optoelectronic silicon waveguide detector,selenium-doped silicon with deep energy levels is used.The deep levels in the silicon with implanted selenium are studied.Three levels are observed and their captured cross sections,concentrations and in-depth profiles are measured.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No.60086001the Special Funds for the Major State Basic Research Project of China under Grant No.G20000683.
文摘High-quality and high-resistivity GaN films were grown on (0001) sapphire face by metal-organic vapour phase epitaxy. To measure the surface acoustic wave properties accurately, we deposited metallized interdigital trans ducers on the GaN surface. The acoustic surface wave velocity and electromechanical coupling coefficient were measured, respectively, to be 5667m/s and 1.9% by the pulse method.
基金Supported by the National Natural Science Foundation of China under Grant Nos 60976046,60837001 and 61021003the National Basic Research Program of China under Grant No 2012CB934204.
文摘Electrochemical capacitance-voltage profiling,Raman and absorption spectroscopy measurements are employed to characterize the electronic and optical properties of silicon supersaturated with sulfur above the equilibrium solubility limit.Silicon wafers are ion implanted with 50keV 32S+ to a dose of 1 × 10^(16) ions/cm^(2) and subsequently irradiated by femtosecond pulses at a fluence of 0.2 J/cm^(2),followed by thermal annealing at 825K for 30min.The spectral response of the photodiode fabricated from the laser-irradiated sample is also investigated.It is found that femtosecond laser irradiation and subsequent thermal annealing can electrically and optically activate the supersaturated sulfur dopant in silicon,as well as reduce the implantation-induced damage in the silicon lattice.
基金Supported by the National Natural Science Foundation of China under Grant Nos 60976046,60776046,60837001 and 61021003the National Basic Research Program of China(973 Program)(2010CB933800).
文摘Optical and electrical properties of single-crystal Si supersaturated with Se by ion implantation and followed by different thermal annealing conditions are reported.Si is implanted with 1×10^(16) cm^(-2) Se ions at 100 keV.The total substitutional fraction of Se atoms in Si is 45%under the annealing at 800℃ for 30 min and the peak concentration of substitutional Se atoms is exceeded 1×10^(20) cm^(-3).A temperature-independent carrier concentration of 3×10^(19) cm^(-3) is measured and the near-infrared absorption is closed to 30%.These results indicate the insulator-to-metal transition of the doped layer and the formation of impurity bands in the Si band gap.
基金Supported by the National Natural Science Foundation of China under Grant Nos 60776046,60976046,60837001 and 61021003the National Basic Research Program of China under Grant Nos 2006CB302802 and 2010CB933800。
文摘To transfer a photon with a 1.55μm wavelength into an electron in an integrated optoelectronic silicon waveguide detector,selenium-doped silicon with deep energy levels is used.The deep levels in the silicon with implanted selenium are studied.Three levels are observed and their captured cross sections,concentrations and in-depth profiles are measured.
