Micro-grains of wurtzite boron nitride(wBN)crystal have been observed in the region of 5.0-7.0 GPa pressure and 1800-2000 K temperature where cubic boron nitride has been synthesized in the presence of a catalyst.The ...Micro-grains of wurtzite boron nitride(wBN)crystal have been observed in the region of 5.0-7.0 GPa pressure and 1800-2000 K temperature where cubic boron nitride has been synthesized in the presence of a catalyst.The wBN grain size is about 20-30nm.The presence of these micro-grains indicates that the pressure for wBN growth could be lower than that found in the previous work.展开更多
Gallium nitride crystals in nano-scale have been fabricated by dc arc plasma method using gallium and N_(2)+NH_(3) as starting materials.Transmission electron microscope,selected area diffraction and x-ray diffraction...Gallium nitride crystals in nano-scale have been fabricated by dc arc plasma method using gallium and N_(2)+NH_(3) as starting materials.Transmission electron microscope,selected area diffraction and x-ray diffraction investigation of the as-grown GaN crystals show that the well faceted crystals are single crystalline GaN in wurtzite structure having lattice constants a_(0)=3.18Åand c_(0)=5.18Å.展开更多
P-type semiconducting polycrystalline diamond thin films doped with boron were synthesized on single crystalline silicon substrate by thermal chemical vapor deposition from a tungsten filament and placing boron-contai...P-type semiconducting polycrystalline diamond thin films doped with boron were synthesized on single crystalline silicon substrate by thermal chemical vapor deposition from a tungsten filament and placing boron-contained substance(boron nitride or elemental boron)on sample holder.The films were determined to be the high quality diamond by Raman spectroscopy,X-ray diffraction and scanning electron microscope measurements.The doping properties of boron were measured by Hall method and infrared absorption.展开更多
基金Supported by the Natinoal Natural Science Foundation of China under Grant No.69576012。
文摘Micro-grains of wurtzite boron nitride(wBN)crystal have been observed in the region of 5.0-7.0 GPa pressure and 1800-2000 K temperature where cubic boron nitride has been synthesized in the presence of a catalyst.The wBN grain size is about 20-30nm.The presence of these micro-grains indicates that the pressure for wBN growth could be lower than that found in the previous work.
文摘Gallium nitride crystals in nano-scale have been fabricated by dc arc plasma method using gallium and N_(2)+NH_(3) as starting materials.Transmission electron microscope,selected area diffraction and x-ray diffraction investigation of the as-grown GaN crystals show that the well faceted crystals are single crystalline GaN in wurtzite structure having lattice constants a_(0)=3.18Åand c_(0)=5.18Å.
文摘P-type semiconducting polycrystalline diamond thin films doped with boron were synthesized on single crystalline silicon substrate by thermal chemical vapor deposition from a tungsten filament and placing boron-contained substance(boron nitride or elemental boron)on sample holder.The films were determined to be the high quality diamond by Raman spectroscopy,X-ray diffraction and scanning electron microscope measurements.The doping properties of boron were measured by Hall method and infrared absorption.
