The growth of lead tungstate(PWO)single crystals and their luminescence properties such as light yield,scintillation decay time,and transmittance were reported.The colourless PWO single crystal has been obtained by us...The growth of lead tungstate(PWO)single crystals and their luminescence properties such as light yield,scintillation decay time,and transmittance were reported.The colourless PWO single crystal has been obtained by using the presyntheses powder.Ba,Nb,and Mg ions were doped in the crystals and the Ba-doped crystal has a relatively short decay time.Annealed crystal was found having a better transmission spectrum than that of unannealed one.展开更多
The influences of the plasma ignition condition in plasma enhanced chemical vapour deposition （PECVD） on the interfaces and the microstructures of hydrogenated microcrystalline Si （μc-Si：H） thin films are invest...The influences of the plasma ignition condition in plasma enhanced chemical vapour deposition （PECVD） on the interfaces and the microstructures of hydrogenated microcrystalline Si （μc-Si：H） thin films are investigated. The plasma ignition condition is modified by varying the ratio of Sill4 to H2 （RH）. For plasma ignited with a constant gas ratio, the time-resolved optical emission spectroscopy presents a low value of the emission intensity ratio of Ha to Sill＊ （Iuα//SiH＊） at the initial stage, which leads to a thick amorphous incubation layer. For the ignition condition with a profiling RH, the higher IHα/ISiH＊ values are realized. By optimizing the RN modulation, a uniform crystallinity along the growth direction and a denser αc-Si：H film can be obtained. However, an excessively high IRα/ISIH＊ may damage the interface properties, which is indicated by capacitance-voltage （C-V） measurements. Well controlling the ignition condition is critically important for the applications of Si thin films.展开更多
文摘The growth of lead tungstate(PWO)single crystals and their luminescence properties such as light yield,scintillation decay time,and transmittance were reported.The colourless PWO single crystal has been obtained by using the presyntheses powder.Ba,Nb,and Mg ions were doped in the crystals and the Ba-doped crystal has a relatively short decay time.Annealed crystal was found having a better transmission spectrum than that of unannealed one.
基金Project supported by the National Basic Research Program of China(Grant Nos.G2006CB202601 and 2011CBA00705)the National Natural Science Foundation of China(Grant No.60806020)the Knowledge Innovation Project of Chinese Academy of Sciences(Grant No.KGCX2-YW-383-1)
文摘The influences of the plasma ignition condition in plasma enhanced chemical vapour deposition （PECVD） on the interfaces and the microstructures of hydrogenated microcrystalline Si （μc-Si：H） thin films are investigated. The plasma ignition condition is modified by varying the ratio of Sill4 to H2 （RH）. For plasma ignited with a constant gas ratio, the time-resolved optical emission spectroscopy presents a low value of the emission intensity ratio of Ha to Sill＊ （Iuα//SiH＊） at the initial stage, which leads to a thick amorphous incubation layer. For the ignition condition with a profiling RH, the higher IHα/ISiH＊ values are realized. By optimizing the RN modulation, a uniform crystallinity along the growth direction and a denser αc-Si：H film can be obtained. However, an excessively high IRα/ISIH＊ may damage the interface properties, which is indicated by capacitance-voltage （C-V） measurements. Well controlling the ignition condition is critically important for the applications of Si thin films.
