We report the observation of the cathode-ray(CR)pumped ultraviolet(UV)super-radiation luminescence in ZnO thin film at room temperature(RT).The dependence of UV(peak at about 390nm)and green(peak at about 520nm)lumine...We report the observation of the cathode-ray(CR)pumped ultraviolet(UV)super-radiation luminescence in ZnO thin film at room temperature(RT).The dependence of UV(peak at about 390nm)and green(peak at about 520nm)luminescent peaks in ZnO thin film under CR excitation on excitation electron beam current has been investigated.With the increase of the density of excitation electron beam current,green peak relatively decreases and UV peak increases,resulting in a change of the luminescent color from green to blue-purple.The green peak intensity increases sublinearly with the increase of the electron beam current density and saturates at a relatively low density of electron beam current.But the intensity of 390nm UV peak increases superlinearly with the increase of the electron beam current density.This is a UV super-radiation luminescence of exciton in ZnO under high density pump.In this paper,three-dimensional atomic force microscope images of the surface of unannealled and annealled ZnO films are given.展开更多
The cathodoluminescence of ZnO films deposited on Si substrates by reactive dc sputtering is investigated.Apart from the characteristic green emission band(522nm)of ZnO,an ultraviolet(392nm)band and a blue(430-460 nm)...The cathodoluminescence of ZnO films deposited on Si substrates by reactive dc sputtering is investigated.Apart from the characteristic green emission band(522nm)of ZnO,an ultraviolet(392nm)band and a blue(430-460 nm)band have been observed.The x-ray diffraction and cathodoluminescent spectra reveal the dependences of the luminescence on the preparation conditions and crystallinity of the ZnO films.展开更多
The photoluminescence of ZnO films deposited on Si substrates by reactive dc sputtering has been studied by using a synchrotron radiation(SR)light source.The excitation spectra show a strong excitation band around 195...The photoluminescence of ZnO films deposited on Si substrates by reactive dc sputtering has been studied by using a synchrotron radiation(SR)light source.The excitation spectra show a strong excitation band around 195 nm related to 390 nm emission band.Under SR vacuum ultraviolet excitation,a new emission band peaked at 290 nm was found for the first time,besides the ultraviolet emission band(390 nm)and green band(520 nm).展开更多
The electrical Properties of a type of semiconductor heterostructure fabricated by depositing zinc oxide film on a silicon substrate are investigated.The I-V,I-T curves,and deep level transient spectra are measured.Fr...The electrical Properties of a type of semiconductor heterostructure fabricated by depositing zinc oxide film on a silicon substrate are investigated.The I-V,I-T curves,and deep level transient spectra are measured.From these results,we acquire the information of the characteristics of the junction,and compute some energy levels of the samples.展开更多
A type of semiconductor heterostructure fabricated by zinc-oxide films deposited on silicon substrates is investigated.The current-voltage characteristics under dark or illumination were determined.Tt is indicated tha...A type of semiconductor heterostructure fabricated by zinc-oxide films deposited on silicon substrates is investigated.The current-voltage characteristics under dark or illumination were determined.Tt is indicated that the sample is likely a semiconductorjunction,and this structure generates an obvious photovoltaic effect.Spectral responses of photovoltage,cathodotoluminescence and excitation spectra at room temperature were employed to study the structural properties and the mechanism generating photovoltaic effect of the samples.The energy level and the process of electron transition in the ZnO film have also been deduced.展开更多
A new method for metalorganic chemical vapor deposition(MOCVD)of GaAs on Si substrates is developed.Instead of the usual high temperature surface cleaning treatment for Si substrate,the new method uses room temperatur...A new method for metalorganic chemical vapor deposition(MOCVD)of GaAs on Si substrates is developed.Instead of the usual high temperature surface cleaning treatment for Si substrate,the new method uses room temperature HF vapor polishing in the preparation chamber in the MOCVD system as the first step of the growth.Single crystal GaAs layers with mirror-like surfaces were obtained.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos.59872037 and 19874057.
文摘We report the observation of the cathode-ray(CR)pumped ultraviolet(UV)super-radiation luminescence in ZnO thin film at room temperature(RT).The dependence of UV(peak at about 390nm)and green(peak at about 520nm)luminescent peaks in ZnO thin film under CR excitation on excitation electron beam current has been investigated.With the increase of the density of excitation electron beam current,green peak relatively decreases and UV peak increases,resulting in a change of the luminescent color from green to blue-purple.The green peak intensity increases sublinearly with the increase of the electron beam current density and saturates at a relatively low density of electron beam current.But the intensity of 390nm UV peak increases superlinearly with the increase of the electron beam current density.This is a UV super-radiation luminescence of exciton in ZnO under high density pump.In this paper,three-dimensional atomic force microscope images of the surface of unannealled and annealled ZnO films are given.
文摘The cathodoluminescence of ZnO films deposited on Si substrates by reactive dc sputtering is investigated.Apart from the characteristic green emission band(522nm)of ZnO,an ultraviolet(392nm)band and a blue(430-460 nm)band have been observed.The x-ray diffraction and cathodoluminescent spectra reveal the dependences of the luminescence on the preparation conditions and crystallinity of the ZnO films.
基金Supported by the National Natural Science Foundation of China under Grant Nos.19874057 and 59872037.
文摘The photoluminescence of ZnO films deposited on Si substrates by reactive dc sputtering has been studied by using a synchrotron radiation(SR)light source.The excitation spectra show a strong excitation band around 195 nm related to 390 nm emission band.Under SR vacuum ultraviolet excitation,a new emission band peaked at 290 nm was found for the first time,besides the ultraviolet emission band(390 nm)and green band(520 nm).
基金Supported by the National Natural Science Foundation of China under Grant No.59872037the Natural Science Foundation of Anhui Province No.98641550.
文摘The electrical Properties of a type of semiconductor heterostructure fabricated by depositing zinc oxide film on a silicon substrate are investigated.The I-V,I-T curves,and deep level transient spectra are measured.From these results,we acquire the information of the characteristics of the junction,and compute some energy levels of the samples.
基金Supported by the National Natural Science Foundation of China under Grant No.59872037the Natural Science Foundation of Anhui Province No.98641550.
文摘A type of semiconductor heterostructure fabricated by zinc-oxide films deposited on silicon substrates is investigated.The current-voltage characteristics under dark or illumination were determined.Tt is indicated that the sample is likely a semiconductorjunction,and this structure generates an obvious photovoltaic effect.Spectral responses of photovoltage,cathodotoluminescence and excitation spectra at room temperature were employed to study the structural properties and the mechanism generating photovoltaic effect of the samples.The energy level and the process of electron transition in the ZnO film have also been deduced.
基金Supported by the National Natural Science Foundation of China under Grant No.8688601.
文摘A new method for metalorganic chemical vapor deposition(MOCVD)of GaAs on Si substrates is developed.Instead of the usual high temperature surface cleaning treatment for Si substrate,the new method uses room temperature HF vapor polishing in the preparation chamber in the MOCVD system as the first step of the growth.Single crystal GaAs layers with mirror-like surfaces were obtained.