Effects of the growth temperature on morphological and microstructural evolution of a-plane GaN films grown on r-plane sapphires by metal organic chemical vapor deposition are investigated by atomic force microscopy a...Effects of the growth temperature on morphological and microstructural evolution of a-plane GaN films grown on r-plane sapphires by metal organic chemical vapor deposition are investigated by atomic force microscopy and secondary ion mass spectroscopy （SIMS）. Surface morphology, structural quality and related impurity incorpora- tion are very sensitive to the growth temperature. A significant difference of yellow luminescence is observed and attributed to the incorporation of carbon into GaN films, which is confirmed by SIMS analysis. Our results show that the sample with triangular-pit morphology has sample with pentagon-like pit morphology, which is significantly higher concentrations of oxygen than the other induced by the existence of an N-face in triangular pits.展开更多
A simplified data set with 8°×8° grid system in a region of 32°S--32°N from 1951 to 1979 for the elements of sea surface temperature (SST), zonal wind at sea level (U), sea level pressure (SLP...A simplified data set with 8°×8° grid system in a region of 32°S--32°N from 1951 to 1979 for the elements of sea surface temperature (SST), zonal wind at sea level (U), sea level pressure (SLP) and total cloud amount (CA) is made from the COADS. The oscillation components with periods of 2 years (QBO), 3.5 years (SO) and 5.5 years (FYO) in interannual low-frequency oscillations have been studied by using the methods of extended EOF (EEOF) and lag correlation analysis with the oscillational components of SST in the equator of eastern Pacific as the reference element. In our paper, the relationship between oscilla- tion components and occurrence of El Nino is also investigated.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 61204006the Fundamental Research Funds for the Central Universities under Grant No K50511250002
文摘Effects of the growth temperature on morphological and microstructural evolution of a-plane GaN films grown on r-plane sapphires by metal organic chemical vapor deposition are investigated by atomic force microscopy and secondary ion mass spectroscopy （SIMS）. Surface morphology, structural quality and related impurity incorpora- tion are very sensitive to the growth temperature. A significant difference of yellow luminescence is observed and attributed to the incorporation of carbon into GaN films, which is confirmed by SIMS analysis. Our results show that the sample with triangular-pit morphology has sample with pentagon-like pit morphology, which is significantly higher concentrations of oxygen than the other induced by the existence of an N-face in triangular pits.
文摘A simplified data set with 8°×8° grid system in a region of 32°S--32°N from 1951 to 1979 for the elements of sea surface temperature (SST), zonal wind at sea level (U), sea level pressure (SLP) and total cloud amount (CA) is made from the COADS. The oscillation components with periods of 2 years (QBO), 3.5 years (SO) and 5.5 years (FYO) in interannual low-frequency oscillations have been studied by using the methods of extended EOF (EEOF) and lag correlation analysis with the oscillational components of SST in the equator of eastern Pacific as the reference element. In our paper, the relationship between oscilla- tion components and occurrence of El Nino is also investigated.
