对PTCDA的分子结构及其化学键的形成进行了分析,并讨论了晶面指数(100)Si单晶的晶格结构。在此基础上,评述了PTCDA分子在P-Si单晶(100)晶面上生长的机理,并制备了样品PTCDA/P-Si(100)。利用XRD对样品测试得出,在P-Si(100)晶面上沉积的PT...对PTCDA的分子结构及其化学键的形成进行了分析,并讨论了晶面指数(100)Si单晶的晶格结构。在此基础上,评述了PTCDA分子在P-Si单晶(100)晶面上生长的机理,并制备了样品PTCDA/P-Si(100)。利用XRD对样品测试得出,在P-Si(100)晶面上沉积的PTCDA薄膜中仅存在α物相。利用XPS对样品测试得出,在其界面层中PTCDA酸酐中的4个羟基O原子与C原子结合,其结合能为532.4 e V;苝核基团外围的8个C、H原子以共价键结合,其结合能为289.0 e V;在界面处,悬挂键上的Si原子与PTCDA酸酐中的C、O原子结合,形成C—Si—O键及C—Si键,构成了界面层的稳定结构。展开更多
Growth of nano Si and Al wires on the Si(100) surfaces is investigated by computer simulation, including the anisotropic diffusion and the anisotropic sticking. The diffusion rates along and across the substrate dimer...Growth of nano Si and Al wires on the Si(100) surfaces is investigated by computer simulation, including the anisotropic diffusion and the anisotropic sticking. The diffusion rates along and across the substrate dimer rows are different, so are the sticking probabilities of an adatom, at the end sites of existing islands or the side sites. Both one\|dimensional wires of Si and Al are perpendicular to the dimer rows of the substrate, though the diffusion of Si adatoms is contrary to that of Al adatoms, i.e. Si adatoms diffuse faster along the dimer rows while Al adatoms faster across the dimer rows. The simulation results also show that the shape anisotropy of islands is due to the sticking anisotropy rather than the diffusion anisotropy, which is in agreement with the experiments.展开更多
Au films with a thickness of about 300 nm were deposited on SiO_2/Si(100) andmica substrates by dc sputtering. X-ray diffraction spectroscopy and field emission scanningelectron microscopy were used to analyze the str...Au films with a thickness of about 300 nm were deposited on SiO_2/Si(100) andmica substrates by dc sputtering. X-ray diffraction spectroscopy and field emission scanningelectron microscopy were used to analyze the structure and internal stress of the Au films. Thefirms grown on SiO_2/Si(100) show a preferential orientation of [111] in the growth direction.However the films grown on mica have mixture crystalline orientations of [111], [200], [220] and[311] in the growth direction and the orientations of [200] and [311] are slightly more than thoseof [111] and [220]. An internal stress in the films grown on SiO_2/Si(100) is tensile. For Au filmsgrown on mica the internal stresses in the [111]- and [311]-orientation grains are compressive whilethose in the [200]- and [220]-orientation grains are tensile. Au films grown SiO_2/Si(100) havesome very large grains with a size of about 400 nm and have a wider grain size distribution comparedwith those grown on mica.展开更多
The epitaxial growth of novel GaN-based light-emitting diode(LED) on Si(100) substrate has proved challenging.Here in this work, we investigate a monolithic phosphor-free semi-polar InGaN/GaN near white light-emitting...The epitaxial growth of novel GaN-based light-emitting diode(LED) on Si(100) substrate has proved challenging.Here in this work, we investigate a monolithic phosphor-free semi-polar InGaN/GaN near white light-emitting diode, which is formed on a micro-striped Si(100) substrate by metal organic chemical vapor deposition. By controlling the size of micro-stripe, InGaN/GaN multiple quantum wells(MQWs) with different well widths are grown on semi-polar(1■01)planes. Besides, indium-rich quantum dots are observed in InGaN wells by transmission electron microscopy, which is caused by indium phase separation. Due to the different widths of MQWs and indium phase separation, the indium content changes from the center to the side of the micro-stripe. Various indium content provides the wideband emission. This unique property allows the semipolar InGaN/GaN MQWs to emit wideband light, leading to the near white light emission.展开更多
文摘对PTCDA的分子结构及其化学键的形成进行了分析,并讨论了晶面指数(100)Si单晶的晶格结构。在此基础上,评述了PTCDA分子在P-Si单晶(100)晶面上生长的机理,并制备了样品PTCDA/P-Si(100)。利用XRD对样品测试得出,在P-Si(100)晶面上沉积的PTCDA薄膜中仅存在α物相。利用XPS对样品测试得出,在其界面层中PTCDA酸酐中的4个羟基O原子与C原子结合,其结合能为532.4 e V;苝核基团外围的8个C、H原子以共价键结合,其结合能为289.0 e V;在界面处,悬挂键上的Si原子与PTCDA酸酐中的C、O原子结合,形成C—Si—O键及C—Si键,构成了界面层的稳定结构。
基金Project Supported by National Natural Science Foundation of China Under Grant !No.4 9672 0 95Natural ScienceFoundation of Zh
文摘Growth of nano Si and Al wires on the Si(100) surfaces is investigated by computer simulation, including the anisotropic diffusion and the anisotropic sticking. The diffusion rates along and across the substrate dimer rows are different, so are the sticking probabilities of an adatom, at the end sites of existing islands or the side sites. Both one\|dimensional wires of Si and Al are perpendicular to the dimer rows of the substrate, though the diffusion of Si adatoms is contrary to that of Al adatoms, i.e. Si adatoms diffuse faster along the dimer rows while Al adatoms faster across the dimer rows. The simulation results also show that the shape anisotropy of islands is due to the sticking anisotropy rather than the diffusion anisotropy, which is in agreement with the experiments.
文摘Au films with a thickness of about 300 nm were deposited on SiO_2/Si(100) andmica substrates by dc sputtering. X-ray diffraction spectroscopy and field emission scanningelectron microscopy were used to analyze the structure and internal stress of the Au films. Thefirms grown on SiO_2/Si(100) show a preferential orientation of [111] in the growth direction.However the films grown on mica have mixture crystalline orientations of [111], [200], [220] and[311] in the growth direction and the orientations of [200] and [311] are slightly more than thoseof [111] and [220]. An internal stress in the films grown on SiO_2/Si(100) is tensile. For Au filmsgrown on mica the internal stresses in the [111]- and [311]-orientation grains are compressive whilethose in the [200]- and [220]-orientation grains are tensile. Au films grown SiO_2/Si(100) havesome very large grains with a size of about 400 nm and have a wider grain size distribution comparedwith those grown on mica.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51472229,61422405,and 11574301)the Natural Science Foundation of Tianjin(Grant No.14JCQNJC01000)the National Science Foundation for Post-doctoral Scientists of China(Grant No.2016M600231)
文摘The epitaxial growth of novel GaN-based light-emitting diode(LED) on Si(100) substrate has proved challenging.Here in this work, we investigate a monolithic phosphor-free semi-polar InGaN/GaN near white light-emitting diode, which is formed on a micro-striped Si(100) substrate by metal organic chemical vapor deposition. By controlling the size of micro-stripe, InGaN/GaN multiple quantum wells(MQWs) with different well widths are grown on semi-polar(1■01)planes. Besides, indium-rich quantum dots are observed in InGaN wells by transmission electron microscopy, which is caused by indium phase separation. Due to the different widths of MQWs and indium phase separation, the indium content changes from the center to the side of the micro-stripe. Various indium content provides the wideband emission. This unique property allows the semipolar InGaN/GaN MQWs to emit wideband light, leading to the near white light emission.
