Diamond crystals were synthesized with different doping proportions of N-H-O at 5.5 GPa-7.1 GPa and 1370℃-1450℃. With the increase in the N-H-O doping ratio, the crystal growth rate decreased, the temperature and pr...Diamond crystals were synthesized with different doping proportions of N-H-O at 5.5 GPa-7.1 GPa and 1370℃-1450℃. With the increase in the N-H-O doping ratio, the crystal growth rate decreased, the temperature and pressure conditions required for diamond nucleation became increasingly stringent, and the diamond crystallization process was affected. [111] became the dominant plane of diamonds;surface morphology became block-like;and growth texture,stacking faults, and etch pits increased. The diamond crystals had a two-dimensional growth habit. Increasing the doping concentration also increased the amount of N that entered the diamond crystals as confirmed via Fourier transform infrared spectroscopy. However, crystal quality gradually deteriorated as verified by the red-shifting of Raman peak positions and the widening of the Raman full width at half maximum. With the increase in the doping ratio, the photoluminescence property of the diamond crystals also drastically changed. The intensity of the N vacancy center of the diamond crystals changed, and several Ni-related defect centers, such as the NE1 and NE3 centers, appeared. Diamond synthesis in N-H-O-bearing fluid provides important information for deepening our understanding of the growth characteristics of diamonds in complex systems and the formation mechanism of natural diamonds, which are almost always N-rich and full of various defect centers. Meanwhile, this study proved that the type of defect centers in diamond crystals could be regulated by controlling the N-H-O impurity contents of the synthesis system.展开更多
We carried out a proof-of-principle demonstration of the reconstruction of a static vector magnetic field involving adjacent three nitrogen-vacancy(NV) sensors with corresponding different NV symmetry axes in a bulk d...We carried out a proof-of-principle demonstration of the reconstruction of a static vector magnetic field involving adjacent three nitrogen-vacancy(NV) sensors with corresponding different NV symmetry axes in a bulk diamond. By means of optical detection of the magnetic resonance(ODMR) techniques, our experiment employs the continuous wave(CW) to monitor resonance frequencies and it extracts the information of the detected field strength and polar angles with respect to each NV frame of reference. Finally, the detected magnetic field relative to a fixed laboratory reference frame was reconstructed from the information acquired by the multi-NV sensor.展开更多
At the vacuum-ultraviolet (VUV) beam line of a synchrotron, an end station for photoluminescence (PL) coupled to a system to detect absorption is used to investigate the luminescence and absorption of materials. We an...At the vacuum-ultraviolet (VUV) beam line of a synchrotron, an end station for photoluminescence (PL) coupled to a system to detect absorption is used to investigate the luminescence and absorption of materials. We analyzed a CVD diamond window in wavelength range 160 - 250 nm at 300 and 14 K. The PL excited with VUV light enabled an identification of nitrogen defects in diamond samples. The VUV PL technique is applicable to explore advanced materials including materials with similar wide band gaps, such as boron nitride and aluminum nitride.展开更多
In a traditional hot-filament chemical vapor deposition (HF-CVD) system, highly (111)-textured diamond film was deposited on Si (111) substrate treated by diamond powder ultrasonic scratching or other methods. The rel...In a traditional hot-filament chemical vapor deposition (HF-CVD) system, highly (111)-textured diamond film was deposited on Si (111) substrate treated by diamond powder ultrasonic scratching or other methods. The relationship between the (111)-textured diamond film growth and the nucleation density has been discussed. The morphologies and structures of the films were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Raman spectroscopy.展开更多
Electron spin resonance （ESR） in polycrystalline diamond films grown by dc arc-jet and microwave plasma chemical vapour deposition is studied. The films with nitrogen impurity concentration up to 8 × 10^18 cm^-...Electron spin resonance （ESR） in polycrystalline diamond films grown by dc arc-jet and microwave plasma chemical vapour deposition is studied. The films with nitrogen impurity concentration up to 8 × 10^18 cm^-3 are also characterized by Raman, cathodoluminescence and optical absorption spectra. The ESR signal from P1 centre with g-factor of 2.0024 （nitrogen impurity atom occupying C site in diamond lattice） is found to exhibit an inversion with increasing the microwave power in an H102 resonator. The spin inversion effect could be of interest for further consideration of N-doped diamonds as a medium for masers operated at room temperature.展开更多
The present understanding of diamond heteroepitaxy by bias-enhanced chemical vapour deposition on technologically relevant substrate materials is briefly reviewed. First the early stages of diamond nucleation and the ...The present understanding of diamond heteroepitaxy by bias-enhanced chemical vapour deposition on technologically relevant substrate materials is briefly reviewed. First the early stages of diamond nucleation and the diamond film growth as well as influences of various deposition conditions are described. Then the results of microscopic investigations of the structure of interfaces and of grain boundaries are summarized.展开更多
金刚石是一种用途极为广泛的极限功能材料,本研究在6.5 GPa压力条件下,利用温度梯度法研究了合成腔体中添加三硫化二硼(B_(2)S_(3))时金刚石大单晶的合成.随着B_(2)S_(3)的添加,所合成金刚石的颜色由典型的黄色变为了浅蓝色,而且金刚石...金刚石是一种用途极为广泛的极限功能材料,本研究在6.5 GPa压力条件下,利用温度梯度法研究了合成腔体中添加三硫化二硼(B_(2)S_(3))时金刚石大单晶的合成.随着B_(2)S_(3)的添加,所合成金刚石的颜色由典型的黄色变为了浅蓝色,而且金刚石的生长速率也随之降低.拉曼(Raman)测试表明所制备样品为单一的sp3杂化金刚石相,但对应的Raman特征峰均趋于向低波数移动.借助傅里叶显微红外光谱(FTIR)测试结果,分析发现金刚石内部氮杂质浓度逐渐降低.此外,利用霍尔效应测试表征了所合成金刚石的电输运性能,结果表明B_(2)S_(3)可将(111)晶向金刚石电阻率降低至45.4Ω·cm.然而,当合成体系中同时添加0.002 g B_(2)S_(3)和除氮剂时,对应金刚石晶体的电阻率锐减至0.43Ω·cm,该研究为金刚石在半导体领域中的应用提供了重要的实验依据.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 51772120, 11604246, 51872112, and 11804305)the Project of Jilin Science and Technology Development Plan (Grant No. 20180201079GX)+1 种基金the Fundamental Research Funds for the Central Universities, the Natural Science Foundation of Chongqing, China (Grant No. cstc2019jcyj-msxm X0391)the Science and Technology Research Program of Chongqing Municipal Education Commission (Grant No. KJQN201901405)。
文摘Diamond crystals were synthesized with different doping proportions of N-H-O at 5.5 GPa-7.1 GPa and 1370℃-1450℃. With the increase in the N-H-O doping ratio, the crystal growth rate decreased, the temperature and pressure conditions required for diamond nucleation became increasingly stringent, and the diamond crystallization process was affected. [111] became the dominant plane of diamonds;surface morphology became block-like;and growth texture,stacking faults, and etch pits increased. The diamond crystals had a two-dimensional growth habit. Increasing the doping concentration also increased the amount of N that entered the diamond crystals as confirmed via Fourier transform infrared spectroscopy. However, crystal quality gradually deteriorated as verified by the red-shifting of Raman peak positions and the widening of the Raman full width at half maximum. With the increase in the doping ratio, the photoluminescence property of the diamond crystals also drastically changed. The intensity of the N vacancy center of the diamond crystals changed, and several Ni-related defect centers, such as the NE1 and NE3 centers, appeared. Diamond synthesis in N-H-O-bearing fluid provides important information for deepening our understanding of the growth characteristics of diamonds in complex systems and the formation mechanism of natural diamonds, which are almost always N-rich and full of various defect centers. Meanwhile, this study proved that the type of defect centers in diamond crystals could be regulated by controlling the N-H-O impurity contents of the synthesis system.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11305074,11135002,11804112,and 11275083)the Key Program of the Education Department Outstanding Youth Foundation of Anhui Province,China(Grant No.gxyqZD2017080)+2 种基金the Natural Science Foundation of Anhui Province,China(Grant No.KJHS2015B09)the Open Fund of Anhui Ley Laboratory for Condensed Matter Physics under Extreme Conditions and CAS Key Laboratory of Microscale Magnetic Resonance(Grant No.KLMMR201804)the Fund of Scientific Research Platform of Huangshan University
文摘We carried out a proof-of-principle demonstration of the reconstruction of a static vector magnetic field involving adjacent three nitrogen-vacancy(NV) sensors with corresponding different NV symmetry axes in a bulk diamond. By means of optical detection of the magnetic resonance(ODMR) techniques, our experiment employs the continuous wave(CW) to monitor resonance frequencies and it extracts the information of the detected field strength and polar angles with respect to each NV frame of reference. Finally, the detected magnetic field relative to a fixed laboratory reference frame was reconstructed from the information acquired by the multi-NV sensor.
文摘At the vacuum-ultraviolet (VUV) beam line of a synchrotron, an end station for photoluminescence (PL) coupled to a system to detect absorption is used to investigate the luminescence and absorption of materials. We analyzed a CVD diamond window in wavelength range 160 - 250 nm at 300 and 14 K. The PL excited with VUV light enabled an identification of nitrogen defects in diamond samples. The VUV PL technique is applicable to explore advanced materials including materials with similar wide band gaps, such as boron nitride and aluminum nitride.
基金Sthe Key Project of Chinese Academy of Sciences Knowledge Innovation Program (Grant No. KJCX3. SYW. N10)
文摘In a traditional hot-filament chemical vapor deposition (HF-CVD) system, highly (111)-textured diamond film was deposited on Si (111) substrate treated by diamond powder ultrasonic scratching or other methods. The relationship between the (111)-textured diamond film growth and the nucleation density has been discussed. The morphologies and structures of the films were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Raman spectroscopy.
基金Supported by the National Natural Science Foundation of China under Grant Nos 50372007 and 50572007, Russian Fund for Basic Research under Grant Nos 06-02-39031 and 07-03-00956, and Belarus Republic Foundation for Basic Research under Grant No F05-281.
文摘Electron spin resonance （ESR） in polycrystalline diamond films grown by dc arc-jet and microwave plasma chemical vapour deposition is studied. The films with nitrogen impurity concentration up to 8 × 10^18 cm^-3 are also characterized by Raman, cathodoluminescence and optical absorption spectra. The ESR signal from P1 centre with g-factor of 2.0024 （nitrogen impurity atom occupying C site in diamond lattice） is found to exhibit an inversion with increasing the microwave power in an H102 resonator. The spin inversion effect could be of interest for further consideration of N-doped diamonds as a medium for masers operated at room temperature.
文摘The present understanding of diamond heteroepitaxy by bias-enhanced chemical vapour deposition on technologically relevant substrate materials is briefly reviewed. First the early stages of diamond nucleation and the diamond film growth as well as influences of various deposition conditions are described. Then the results of microscopic investigations of the structure of interfaces and of grain boundaries are summarized.
文摘金刚石是一种用途极为广泛的极限功能材料,本研究在6.5 GPa压力条件下,利用温度梯度法研究了合成腔体中添加三硫化二硼(B_(2)S_(3))时金刚石大单晶的合成.随着B_(2)S_(3)的添加,所合成金刚石的颜色由典型的黄色变为了浅蓝色,而且金刚石的生长速率也随之降低.拉曼(Raman)测试表明所制备样品为单一的sp3杂化金刚石相,但对应的Raman特征峰均趋于向低波数移动.借助傅里叶显微红外光谱(FTIR)测试结果,分析发现金刚石内部氮杂质浓度逐渐降低.此外,利用霍尔效应测试表征了所合成金刚石的电输运性能,结果表明B_(2)S_(3)可将(111)晶向金刚石电阻率降低至45.4Ω·cm.然而,当合成体系中同时添加0.002 g B_(2)S_(3)和除氮剂时,对应金刚石晶体的电阻率锐减至0.43Ω·cm,该研究为金刚石在半导体领域中的应用提供了重要的实验依据.
