High-quality p-type boron-doped IIb diamond large single crystals are successfully synthesized by the temperature gradient method in a china-type cubic anvil high-pressure apparatus at about 5.5 GPa and 1600 K. The mo...High-quality p-type boron-doped IIb diamond large single crystals are successfully synthesized by the temperature gradient method in a china-type cubic anvil high-pressure apparatus at about 5.5 GPa and 1600 K. The morphologies and surface textures of the synthetic diamond crystals with different boron additive quantities are characterized by using an optical microscope and a scanning electron microscope respectively. The impurities of nitrogen and boron in diamonds are detected by micro Fourier transform infrared technique. The electrical properties including resistivities, Hall coefficients, Hall mobilities and carrier densities of the synthesized samples are measured by a four-point probe and the Hall effect method. The results show that large p-type boron-doped diamond single crystals with few nitrogen impurities have been synthesized. With the increase of quantity of additive boron, some high-index crystal faces such as {113} gradually disappear, and some stripes and triangle pits occur on the crystal surface. This work is helpful for the further research and application of boron-doped semiconductor diamond.展开更多
This paper carries out the First principles calculation of the crystal structures （zinc blende （B3） and rocksalt （B1）） and phase transition of boron arsenic （BAs） based on the density-functional theory. Using ...This paper carries out the First principles calculation of the crystal structures （zinc blende （B3） and rocksalt （B1）） and phase transition of boron arsenic （BAs） based on the density-functional theory. Using the relation between enthalpy and pressure, it finds that the transition phase from the B3 structural to the B] structural occurs at the pressure of l13.42GPa. Then the elastic constants Cll, C12, C44, bulk modulus, shear modulus, Young modulus, anisotropy factor, Kleinman parameter and Poisson ratio are discussed in detail for two polymorphs of BAs. The results of the structural parameters and elastic properties in B3 structure are in good agreement with the available theoretical and experimental values.展开更多
基金supported by the Young Scientists Fund of the National Natural Science Foundation of China (Grant No. 51001042)the Doctor Foundation of the Henan Polytechnic University,China (Grant No. 2010-32)
文摘High-quality p-type boron-doped IIb diamond large single crystals are successfully synthesized by the temperature gradient method in a china-type cubic anvil high-pressure apparatus at about 5.5 GPa and 1600 K. The morphologies and surface textures of the synthetic diamond crystals with different boron additive quantities are characterized by using an optical microscope and a scanning electron microscope respectively. The impurities of nitrogen and boron in diamonds are detected by micro Fourier transform infrared technique. The electrical properties including resistivities, Hall coefficients, Hall mobilities and carrier densities of the synthesized samples are measured by a four-point probe and the Hall effect method. The results show that large p-type boron-doped diamond single crystals with few nitrogen impurities have been synthesized. With the increase of quantity of additive boron, some high-index crystal faces such as {113} gradually disappear, and some stripes and triangle pits occur on the crystal surface. This work is helpful for the further research and application of boron-doped semiconductor diamond.
基金supported by the National Natural Science Foundation of China (Grant Nos. 10974139 and 10964002)the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20050610010)+1 种基金the Science-Technology Foundation of Guizhou Province of China (Grant Nos. [2009]2066 and [2009]06)the project of Aiding Elites’ Research Condition of Guizhou Province of China (Grant No. TZJF-2008-42)
文摘This paper carries out the First principles calculation of the crystal structures （zinc blende （B3） and rocksalt （B1）） and phase transition of boron arsenic （BAs） based on the density-functional theory. Using the relation between enthalpy and pressure, it finds that the transition phase from the B3 structural to the B] structural occurs at the pressure of l13.42GPa. Then the elastic constants Cll, C12, C44, bulk modulus, shear modulus, Young modulus, anisotropy factor, Kleinman parameter and Poisson ratio are discussed in detail for two polymorphs of BAs. The results of the structural parameters and elastic properties in B3 structure are in good agreement with the available theoretical and experimental values.
