GLORIA

GEOMAR Library Ocean Research Information Access

X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Online Resource
    Online Resource
    Shape controlled growth for type Ib large diamond crystals
    Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences ; 2018
    In:  Acta Physica Sinica Vol. 67, No. 16 ( 2018), p. 168101-
    Details
    In: Acta Physica Sinica, Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences, Vol. 67, No. 16 ( 2018), p. 168101-
    Abstract: The shape controlled growth of diamond is beneficial to its subsequent processing. The shape controlled growth for abrasive grade diamond, whose particle size is less than 1 mm, has been studied extensively, while the shape controlled growth of large diamond crystals, which have important commercial and scientific applications, has not been investigated in detail. Therefore, it is necessary to do further researches. In this study, we synthesize large type Ib diamond crystals and investigate their growth shapes at pressures of 5.3-5.9 GPa and temperatures of 1200-1370℃, by using Fe64Ni36 alloy as the catalyst and (100) or (111) face of seed as growth face. Experimental results show that for the diamond crystals grown along the (100) face, the crystal shapes presents plate shape at 1206-1215℃, tower shape at 1216-1260℃, and tower steeple shape at 1261-1360℃; in sequence while for those grown along the (111) face, the crystal shape is of tower at 1233-1238℃ and becomes plate at 1239-1364℃. The ratio of height to diameter, which can provide a standard to quantify the shape of a diamond, is used to describe the crystal shape in detail. For large diamond crystals growing along the (100) face, under a high pressure of 5.6 GPa, the ratio of height to diameter increases with temperature increasing but the ratio of height to diameter, when growing along the (111) face, decreases. The shape distributions of large diamond crystals in the V-shaped region can be determined in the experiments of large diamond crystal synthesis at different temperatures (1200-1370℃) and pressures (5.3 GPa, 5.6 GPa, 5.9 GPa). The lower limit temperature of large diamond crystal growing along the (111) face in the V-shape region is obviously higher than that growing along the (100) face, but the difference between the higher limit temperatures for growing along these two faces is not obvious. The difference between the lower temperature limits of large diamond crystals growing along the (100) and (111) face can be explained by the different energies of the crystal surface and diamond/graphite equilibrium line in the phase diagram of carbon/alloy. Therefore, it has been realized that the shapes for type Ib large diamond crystals are controlled.
    Type of Medium: Online Resource
    ISSN: 1000-3290 , 1000-3290
    URL: Journal
    URL: Article
    DOI: 10.7498/aps
    DOI: 10.7498/aps.67.20180356
    Language: Unknown
    Publisher: Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences
    Publication Date: 2018
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    Finite element analysis of the high-pressure tungsten carbide radius-anvil
    Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences ; 2012
    In:  Acta Physica Sinica Vol. 61, No. 4 ( 2012), p. 040702-
    Details
    In: Acta Physica Sinica, Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences, Vol. 61, No. 4 ( 2012), p. 040702-
    Abstract: The high-pressure tungsten carbide (WC) radius-anvil is analyzed and studied based on the finite element method (FEM). The results indicat that under the same transfer efficiency of pressure, the lifetime of high-pressure WC radius-anvil is longer than that of the traditional anvil, which can be enhanced about 3.05%16.75%. The highest sample cell pressure generation by the new design of high-pressure WC radius-anvil increases about 5% (from 5.80 GPa to 6.09 GPa) compared with that by the traditional anvil, which can be attributed to the technology of radius-bevel. The high-pressure WC radius-anvil will be indeed very useful to broaden the synthetic region of functional materials. Further more, in this work, the operational costs of cubic high-pressure apparatus is reduced and the cubic anvil type high pressure techniques is improved in many important aspects.
    Type of Medium: Online Resource
    ISSN: 1000-3290 , 1000-3290
    URL: Journal
    URL: Article
    DOI: 10.7498/aps
    DOI: 10.7498/aps.61.040702
    Language: Unknown
    Publisher: Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences
    Publication Date: 2012
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    Synthesis and electrical properties study of Ib type diamond single crystal co-doped with boron and hydrogen under HPHT conditions
    Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences ; 2016
    In:  Acta Physica Sinica Vol. 65, No. 11 ( 2016), p. 118103-
    Details
    In: Acta Physica Sinica, Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences, Vol. 65, No. 11 ( 2016), p. 118103-
    Abstract: Diamond is well known for its excellent properties, such as its hardness, high thermal conductivity, high electron and hole mobility, high breakdown field strength and large band gap (5.4 eV), which has been extensively used in many fields. However, its application in semiconductor area needs to be further understood, because it is irreplaceable by conventional semiconductor materials, especially in the extreme working conditions. In order to obtain diamond semiconductor with excellent electrical performances, diamond crystals co-doped with boron (B) and hydrogen (H) are synthesized in an FeNi-C system by temperature gradient growth (TGG) at pressure 6.0 GPa and temperature 1600 K. Fourier infrared spectra (FTIR) measurements displayed that H is the formation of sp3 CH2-antisymmetric and sp3 -CH2-symmetric vibrations in the obtained diamond. Furthermore, the corresponding absorption peaks of H element are located at 2920 cm-1 and 2850 cm-1, respectively. Hall effects measurements demonstrated that the co-doped diamond exhibited that p- type material semiconductor performance, and the conductivity of the co-doped diamond is significantly enhanced comparing tocompared with the conductivity of the B-doping diamond. The results indicated that the Hall mobility mobilities is nearly equivalent between B-doped and co-doped diamond crystals are nearly equivalent, while the concentrations of the carriers and conductivity of the co-doped diamonds are higher than those of the B-doped diamond crystals. It is also noticed that the nitrogen concentration of the co-doped diamond decreases obviously, when the H and B are introduced into the diamond structure. Additionally, the change of the conductivity is investigated by first-principles calculation. In the B-doping diamond, two impurity levels are located in the forbidden band with small gaps. These impurity states above the Fermi level couldcan trap the photo-excited electrons, while those below Fermi level can trap the photo-excited vacancies, improving the transfer of the photo-excited carriers to the reactive sites. With the H co-doped diamond, the two impurity states moved to the valance band maximum and merged into each other, which extends the valance band and improves the charge transfer efficiency. From the perspective of energy band, for the co-doped of B and N atoms co-doped diamond, the impurity states are contributed by N/B-2p states while the overlop and splitting of N/B-2p in the band gap appeared. For the H co-doped diamond, the splitting of the N/B-2p states vanishes and shifts to the lower energy level, which was due to the fact that the excess charge transferred from N to H. The calculation results above are in qualitatively agreement with experimental results. We hope that this investigation would be meaningful for the application of diamond in semiconductor field.
    Type of Medium: Online Resource
    ISSN: 1000-3290 , 1000-3290
    URL: Journal
    URL: Article
    DOI: 10.7498/aps
    DOI: 10.7498/aps.65.118103
    Language: Unknown
    Publisher: Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences
    Publication Date: 2016
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 4
    Online Resource
    Online Resource
    Characterization of typical infrared characteristic peaks of hydrogen in nitrogen and hydrogen co-doped diamond crystals
    Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences ; 2014
    In:  Acta Physica Sinica Vol. 63, No. 4 ( 2014), p. 048101-
    Details
    In: Acta Physica Sinica, Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences, Vol. 63, No. 4 ( 2014), p. 048101-
    Abstract: The 3107 cm-1 peak is observed in the infrared absorption spectra of all types of Ia diamonds, but it has not been observed in the iron-based catalyst. A series of nitrogen and hydrogen-doped diamond crystals is successfully synthesized using P3N5 as the nitrogen source in a catalyst-carbon system at a lower pressure and temperature (6.3 GPa, 1500 ℃). Fourier transform infrared micro-spectroscopy reveals that the hydrogen atoms existing in the synthesized diamond are in two forms. The one is attributed to the CH bond stretching (3107 cm-1) and bending (1405 cm-1) vibrations of the vinylidene group (C＝CH2). The other is due to sp3 hybridization CH bond symmetric (2850 cm-1) and anti-symmetric (2920 cm-1) vibrations. According to our result, we find that the 3107 cm-1 hydrogen absorption peak is related to the aggregated nitrogen in synthetic diamond. The 3107 cm-1 peak could not be observed in synthetic diamond without aggregated nitrogen, even if it has a high nitrogen concentration. And the hydrogen absorption peaks at 2920 and 2850 cm-1 are more widespread than the absorption peak at 3107 cm-1, this suggests that the sp3 CH bond more widely exists in diamond than the vinylidene group (C＝CH2). Infrared spectra analysis indicates that the hydrogen impurity mainly exists in the natural diamond as vinylidene group as seen from the absorption peak intensity. We believe that our results provide a new way to study the formation mechanism of the natural diamond. Moreover, the ideal synthesis condition in our system supplies a possible way for us to design n-type diamond semiconductor.
    Type of Medium: Online Resource
    ISSN: 1000-3290 , 1000-3290
    URL: Journal
    URL: Article
    DOI: 10.7498/aps
    DOI: 10.7498/aps.63.048101
    Language: Unknown
    Publisher: Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences
    Publication Date: 2014
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 5
    Online Resource
    Online Resource
    Effects of nitrogen and hydrogen co-doped on {100}-oriented single diamond under high temperature and high pressure
    Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences ; 2015
    In:  Acta Physica Sinica Vol. 64, No. 22 ( 2015), p. 228101-
    Details
    In: Acta Physica Sinica, Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences, Vol. 64, No. 22 ( 2015), p. 228101-
    Abstract: As is well known, most natural diamonds usually contain not only aggregated nitrogen up to thousands of ppm but also hydrogen. Therefore, the studies of nitrogen and hydrogen impurities in a diamond are of interest for improving the physical properties of a diamond and solving the problems about natural diamond genesis. From this point of view, in this paper, we choose C3N6H6 powders as a nitrogen and hydrogen source and select high-quality seed crystals with {100} facets as the growth facets. The effects of nitrogen and hydrogen co-doped on {100}-oriented single diamond in the NiMnCo-C system at pressures ranging from 5.5 GPa to 6.2 GPa and temperatures of 1280-1450 ℃ are investigated. Experimental results show that both pressure and temperature, which are the synthesis conditions, increase with the increases of nitrogen and hydrogen content in diamond-growth environment, and the V-shape region of diamond-forming moves up. From the obtained Fourier transform infrared spectra, we notice that there is a significant change of the nitrogen concentration in the synthesized diamond with increasing the nitrogen and hydrogen content in the diamond-growth environment. We calculate the nitrogen concentrations in those diamonds and the results indicate that the highest concentration of nitrogen is up to 2000 ppm. Meanwhile, we notice that the hydrogen associated infrared peaks of 2850 and 2920 cm-1 are gradually enhanced, which shows that both nitrogen and hydrogen are successfully co-doped into the diamond. Scanning electron microscope micrographs show that the {111} face is elongated and has triangulated textures appearing on the surface with nitrogen and hydrogen co-doped into the diamond. This result indicates that the synergistic doping of nitrogen and hydrogen has a great influence on the morphology of {100}-oriented single diamond. From the obtained Raman spectra, we find a shift towards higher frequency of the Raman peak from 1330.23 cm-1 to 1330.40 cm-1 and the full width at half maximum increases from 3.12 cm-1 to 4.66 cm-1 with increasing the concentrations of nitrogen and hydrogen in diamond-growth environment. This is the first report about nitrogen and hydrogen co-doped on 100-oriented single diamond by far. This work can provide a new method to study the influences of nitrogen and hydrogen impurities on diamond synthesis and it will help us to further understand the genesis of natural diamond in the future.
    Type of Medium: Online Resource
    ISSN: 1000-3290 , 1000-3290
    URL: Journal
    URL: Article
    DOI: 10.7498/aps
    DOI: 10.7498/aps.64.228101
    Language: Unknown
    Publisher: Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences
    Publication Date: 2015
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 6
    Online Resource
    Online Resource
    Finite element method study on the temperature distribution in the cell of large single crystal diamond
    Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences ; 2010
    In:  Acta Physica Sinica Vol. 59, No. 3 ( 2010), p. 1923-
    Details
    In: Acta Physica Sinica, Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences, Vol. 59, No. 3 ( 2010), p. 1923-
    Abstract: The temperature distribution in the cell of single crystal diamond grown by the temperature gradient method has been studied, which is based on the finite element method. Our results shwo that the temperature distribution in the synthetic process of single crystal diamond is not uniform. The highest temperature in the cell is located at the outside of single carbon solvent, and the lowest temperature in the cell is located near the diamond seed. The heat transfer and the mass transport have a same direction （from outside of carbon source to diamond seed）. The temperature gradient in the axial direction is higher than that in the radial direction, which explains why the size of synthetic single crystal diamond in the axial direction is larger than that in the radial direction. The model will be useful for the design of single crystal diamond grown by the temperature gradient method. Furthermore, this work will be hopeful to improve the cubic anvil type high pressure techniques for the synthesis of high quality diamond crystals.
    Type of Medium: Online Resource
    ISSN: 1000-3290 , 1000-3290
    URL: Journal
    URL: Article
    DOI: 10.7498/aps
    DOI: 10.7498/aps.59.1923
    Language: Unknown
    Publisher: Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences
    Publication Date: 2010
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 7
    Online Resource
    Online Resource
    Research on mechanism of carbon transformation in the preparation of polycrystalline diamond by melt infiltration and growth method under high pressures
    Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences ; 2016
    In:  Acta Physica Sinica Vol. 65, No. 6 ( 2016), p. 068101-
    Details
    In: Acta Physica Sinica, Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences, Vol. 65, No. 6 ( 2016), p. 068101-
    Abstract: Recently, a variety of carbon materials can be turned into pure polycrystalline diamond directly without any additives under extreme high pressures and high temperatures (pressure above 13 GPa and temperature above 2000 ℃). Polycrystalline diamond shows a broad application prospect because of its superior performance. However, it is difficult to realize the industrialization of pure polycrystalline diamond on current high pressure equipment due to the high synthetic conditions. The focus of our work is that the synthesis of pure polycrystalline diamond can be realized in the same synthesis range of single diamond produced from the solvent metal (pressure below 6 GPa and temperature below 1500 ℃). The carbon materials can precipitate from the solution in a form of diamond, and fill into the gaps between the diamond particles. According to some domestic scholars' researches on polycrystalline diamond, the solvent method can reduce the high temperature and high pressure conditions on which carbon may transform into diamond directly, and precipitate from the solution in the form of diamond into the gaps between diamond particles. Through a deep study of the approach, the low addition content, even pure polycrystalline diamond without gaps can be prepared. In this paper we have prepared pure polycrystalline diamonds under relatively lower conditions (the pressure being below 6 GPa and the temperature below 1500 ℃) by the method that the metal solution layer infiltrates into the gaps between the pure diamond particles and then the diamond particles will grow up. We also carry out a research on the mechanism of carbon transformation in the preparation of polycrystalline diamond. Compared with the traditional method of powder mixing technology, the melt infiltration and growth method is more advantageous to prepare high abrasive resistance and high density pure polycrystalline diamond.In order to prepare pure flawless polycrystalline diamonds without additives by China-type large volume cubic high-pressure apparatus (CHPA) (SPD-61200), we study thoroughly on the melt infiltration and growth method under high pressures; and this provides a theoretical guidance for pure polycrystalline diamond synthesis. In this paper, polycrystalline diamond is prepared by melt infiltration and growth method at pressures below 6 GPa and temperatures below 1500 ℃. Mechanism research of carbon transformation is made under high pressure and high temperature (HPHT). Through the analyses of optical microscope, X-ray diffraction, and field emission scanning electron microscope measurements, graphitization occurs on the surface of diamond in the procedure of metal solution infiltrating, and then the generated graphite quickly change into diamond-like carbon under HPHT. Meanwhile, the morphology of diamond particles changes distinctly in the syntheses process. From the analysis of experimental phenomena, carbon may undergo three transformations in the preparation: 1) graphite is generated due to the graphitization on the surface of diamond particles, which is caused by the metal solution infiltrating; 2) the generated graphite quickly fills into the gap with the form of diamond-like carbon during the sintering stage; 3) the diamond-like carbon is dissolved in a metal solution, and then precipitates between particles in the form of diamond. The mechanism research on carbon source transformation plays an important guiding role in the industrialization of no-additive, no-gap pure polycrystalline diamond preparation.
    Type of Medium: Online Resource
    ISSN: 1000-3290 , 1000-3290
    URL: Journal
    URL: Article
    DOI: 10.7498/aps
    DOI: 10.7498/aps.65.068101
    Language: Unknown
    Publisher: Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences
    Publication Date: 2016
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 8
    Online Resource
    Online Resource
    Synthesis and growth mechanism of high length-diameter ratio strip-shape diamond by HPHT
    Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences ; 2012
    In:  Acta Physica Sinica Vol. 61, No. 7 ( 2012), p. 078102-
    Details
    In: Acta Physica Sinica, Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences, Vol. 61, No. 7 ( 2012), p. 078102-
    Abstract: To extend the kind of diamond and solve the low life of diamond tools because of the insufficiency of holding force, the strip-shape diamond with more than 2.5 in length-diameter ratio and 0.81.0 mm in length is synthesized by optimizing FeNi based catalyst composition and using the technology in the China-type cubic anvil high pressure apparatus. Because of the unique morphology, the threshing phenomenon appearing in the using of diamond tools is controlled effectively. Furthermore, we find that the growth rate of strip-shape diamond is much faster than that of the conventional diamond. Strip-shape diamond morphology and catalyst composition around the growing diamond crystal are characterized by SEM and EDS. The results indicate that the facets of diamond crystal are elongated along {100} and {111} faces and catalyst compositions around the growing diamond crystal become segregated. On this basis, we illustrate the growth mechanism of strip-shape diamond.
    Type of Medium: Online Resource
    ISSN: 1000-3290 , 1000-3290
    URL: Journal
    URL: Article
    DOI: 10.7498/aps
    DOI: 10.7498/aps.61.078102
    Language: Unknown
    Publisher: Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences
    Publication Date: 2012
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 9
    Online Resource
    Online Resource
    Finite element simulations of thermal-stress on cemented tungsten carbide anvil used in cubic high pressure apparatus
    Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences ; 2009
    In:  Acta Physica Sinica Vol. 58, No. 7 ( 2009), p. 4812-
    Details
    In: Acta Physica Sinica, Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences, Vol. 58, No. 7 ( 2009), p. 4812-
    Abstract: Based on the theoretical analysis, we performed finite element simulation of high pressure experiment in multi-anvil devices （XKY-6×2000 MN） to determine the temperature and the stress in WC anvil. The simulated results show that the temperature is not uniform, and the ununiform temperature can produce thermal-shear stress in the anvil. The peak value of thermal-shear stress lies on the beveling edge of the anvil, the peak value of thermal-shear stress is 0.62 GPa, which is 18 percent that of unheated anvil. The simulation results have been verified by high pressure synthesis experiment. We developed a new method to simulate the stress of WC anvil at high pressure and high temperature. This would greatly help the design of anvil with safe dimension.
    Type of Medium: Online Resource
    ISSN: 1000-3290 , 1000-3290
    URL: Journal
    URL: Article
    DOI: 10.7498/aps
    DOI: 10.7498/aps.58.4812
    Language: Unknown
    Publisher: Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences
    Publication Date: 2009
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 10
    Online Resource
    Online Resource
    Synthesis of gem diamond crystals by multiseed method using China-type cubic high-pressure apparatus
    Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences ; 2013
    In:  Acta Physica Sinica Vol. 62, No. 18 ( 2013), p. 188103-
    Details
    In: Acta Physica Sinica, Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences, Vol. 62, No. 18 ( 2013), p. 188103-
    Abstract: In this paper, gem diamond synthesis is systematically studied using the multiseed method in China-type cubic high-pressure apparatus. High-quality Ib diamond crystals are synthesized in a growth cell with 3-5 diamond seeds, by adjusting the growth cell assembly and investigating the pressure and temperature regions of diamond synthesis. Because of several diamond seeds embedded in a growth cell, the synthesized diamond crystals possess the same morphology and quality. At the same time, the whole growth rate increases apparently. Using the multiseed method of diamond synthesis the growth cell volume can be effectively utilized, the efficiency of diamond synthesis can be enhanced, and the problem of low utilization rate is solved. Meanwhile, those also provide an effective support for the gem diamond industrialization synthesis.
    Type of Medium: Online Resource
    ISSN: 1000-3290 , 1000-3290
    URL: Journal
    URL: Article
    DOI: 10.7498/aps
    DOI: 10.7498/aps.62.188103
    Language: Unknown
    Publisher: Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences
    Publication Date: 2013
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...