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Rare Metals 2017年第4期36卷 289-294页

作者： Ran Teng Qing Chang Yang Li Bin Cui Qing-Hua Xiao Guo-Hu Zhang National Engineering Research Center for Semiconductor Materials Beijing 100088 China General Research Institute for Nonferrous Metals Semiconductor Materials Co. Ltd Beijing 100088 China

Numerical analysis is an effective tool to research the industrial czochralski （CZ） crystal growth aiming to improve crystal quality and reduce manufactur- ing costs. In this study, a set of global simulations were carried out to investigate the effect of crystal-crucible rotation and pulling rate on melt convection and solid- liquid （SL） interface shape. Through analyses of the sim- ulation data, it is found that the interface deformation and inherent stress increase during the crystal growth process. The interface deflection increases from 7.4 to 51.3 mm with an increase in crystal size from 150 to 400 mm. In addition, the SL interface shape and flow pattern are sen- sitive to pulling rate and rotation rate. Reducing pulling rate can flat SL interface shape and add energy-consuming. Interface with low deflection can be achieved by adopting certain combination of crystal and crucible rotation rates. The effect of crystal rotation on SL interface shape is less significant at higher crucible rotation rates.

关键词： czochralski method Numerical analysis Pullrate Crucible rotation Crystal rotation Solid/liquidinterface shape

Structure and Optical Properties of ZnO Thin Films Prepared by the czochralski method

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Journal of Wuhan University of Technology(Materials Science) 2022年第5期37卷 823-828页

作者： MA Zhanhong REN Fengzhang YANG Zhouya School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang471023China Provincial and Ministerial Co-construction of Collaborative Innovation Center for Non-ferrous Metal New Materials and Advanced Processing Technology Luoyang471023China

The zinc oxide seed film was coated on conductive glass (FTO) substrate by the czochralski method,Zinc acetate and hexamethylenetetramine were used as raw materials to prepare growth solution,and then ZnO film was prepared by a low-temperature solution *** effects of annealing temperature on the morphology,structure,stress and optical properties of ZnO films were *** thin films were characterized by X-ray diffraction (XRD),scanning electron microscopy (SEM),UV-visible absorption spectra (UV-vis),photoluminescence (PL) and X-ray photoelectron spectroscopy (XPS).The results show that the films are ZnO *** the increase of annealing temperature,the diameter of the rod increases,and the nanorods tend to be *** band gap of the sample obtained from the light absorption spectra first increases and then decreases with the increase of annealing *** the annealing temperature is 350 ℃,the crystallinity of zinc oxide film is the highest,the band gap is close to the theoretical value of pure ZnO.

关键词： czochralski method ZnO film annealing temperature optical properties micro-morphology internal stress

Growth and Spectral Properties of Yb^(3+)-doped Ba_3Gd(BO_3)_3 Crystal

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Chinese Journal of Structural Chemistry 2007年第10期26卷 1153-1158页

作者：潘尚可陆晟丁栋舟任国浩张卫东王国富潘建国 Shanghai Institute of Ceramics The Chinese Academy of Sciences Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences State Key Laboratory Base of Novel Functional Materials and Preparation Science Ningbo University

Crystal of Yb^3＋-doped Ba3Gd（BO3）3 has been grown by the czochralski method. The spectroscopic characterizations have been investigated at room temperature. The Yb^3＋：Ba3Gd（BO3）3 crystal exhibits broad absorption at 976 nm with FWHM of 7 nm and large overall spitting of ^2F7/2 manifold （823 cm^-1）. The absorption and emission cross sections are 5.09×10^-21 cm^2 at 976 nm and 0.97×10^-21 cm^2 at 1040 nm, respectively. The fluorescence lifetime is 2.84 ms.

关键词： solid solution czochralski method borate solid-state laser materials

Growth and Characterization of High-quality LiAlO2 Single Crystal

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Journal of Materials Science & Technology 2008年第2期24卷 145-148页

作者： Taohua HUANG Shengming ZHOU Hao TENG Hui LIN Jun ZOU Jianhua ZHOU Jun WANG Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

γ-LiAlO2 single crystal is a promising substrate for GaN heteroepitaxy. In this paper, we present the growth of large-sized LiAlO2 crystal by modified czochralski method. The crystal quality was characterized by high-resolution X-ray diffraction and chemical etching. The results show that the as-grown crystal has perfect quality with the full width at half maximum （FWHM） of 17.7-22.6 arcsec and etch pits density of （0.3- 2.2）×10^4 cm^-2 throughout the crystal boule. The bottom of the crystal boule shows the best quality. The optical transmission spectra from UV to IR exhibits that the crystal is transparent from 0.2 to 5.5μm and becomes completely absorbing around 6.7μm wavelength, The optical absorption edge in near UV region is about 191 nm.

关键词： γ-LiAlO2 crystal czochralski method Chemical etching Transmission spectra

Fast growth of cerium-doped lutetium yttrium orthosilicate single crystals and their scintillation properties

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Journal of Rare Earths 2021年第12期39卷 1527-1532,I0003页

作者： Kunfeng Chen Dongfeng Xue State Key Laboratory of Crystal Materials Institute of Crystal MaterialsShandong UniversityJi'nan 250100China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesShenzhen 518055China Multiscale Crystal Materials Research Center Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesChangchun 130022China

The growth of high-quality and large-size cerium-doped lutetium yttrium orthosilicate(Ce:(LuY)2 SiO5,Ce:LYSO)crystals with lower cost has great influence on their applications in various physical *** to the chemical bonding theory of single crystal growth,the fast thermodynamic growth direction of Ce:LYSO is[010]*** this work,the maximum pulling rate of 3.5 mm/h is obtained along[010]direction of Ce:LYSO via the czochralski(Cz)***,Ce:LYSO bulk single crystals with diameter of 64 mm and length of 220 mm and mass of 4.2 kg are *** luminescence performance of low-doped Ce:LYSO for nuclear irradiation(^(22)Na)detector device was *** yield of26193 ph/MeV and decay time of 38 ns are *** present work provides a promising fast growth approach to achieving large size functional bulk crystal via both thermodynamic and kinetic controls.

关键词： Crystal growth LYSO czochralski method Chemical bonding theory Inorganic scintillator Rare earths

Influence of Gamma-Ray Irradiation on Absorption and Fluorescent Spectra of Nd：YAG and Yb：YAG Laser Crystals

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Chinese Physics Letters 2008年第6期25卷 2081-2084页

作者：孙敦陆张庆礼肖敬忠罗建乔江海河殷绍唐 Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Hefei 230031 Department of Ceramics and Glass Engineering CICECO University of A veiro A veiro 3810-193 Portugal

We investigate the influence of gamma-ray irradiation on the absorption and fluorescent spectra of Nd^3＋：Y3A15 O12 （Nd： YAG） and Yb^3＋： Y3A15 O12 （Yb： YAG） crystals grown by the czochralski method. Two additional absorption （AA） bands induced by gamma-ray irradiation appear at 255nm and 340nm. The former is contributed due to Fe^3＋ impurity, the latter is due to Fe^2＋ ions and F-type colour centres. The intensity of the excitation and emission spectra as well as the fluorescent lifetime of Nd：YAG crystal decrease after the irradiation of 100 Mrad gamma-ray. In contrast, the same dose irradiation does not impair the fluorescent properties of Yb：YAG crystal. These results indicate that Yb： YA G crystal possesses the advantage over Nd： YA G crystal that has better reliability for applications in harsh radiant environment.

关键词： INDUCED COLOR-CENTERS czochralski method GROWTH

Determination of Ge content in high concentration Ge-doped czochralski Si single crystals by FTIR

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Rare Metals 2005年第3期24卷 226-228页

作者： JIANG Zhongwei ZHANG Weilian NIU Xinhuan Institute of Information Functional Materials Hebei University of Teclmology Tianjin 300130 China

SiGe single crystals with different Ge concentrations were measured by Fourier transform infrared （FTIR） spectroscopy at room temperature （RT） and 10 K. A new peak appears at the wave number of 710 cm^-1 and the spectroscopy becomes clearer with an increase in Ge content. The absorption strength and wave sharp of the 710 cm^-1 peak are independent of temperature. The relation of the absorption coefficient amax, the band width of half maximum （BWHM） Wit2 of the 710 cm^-1 peak, and the Ge concentration is determined with the Ge content obtained by SEM-EDX. The conversion factor is k = 1.211 at 10 K. Therefore, the Ge content in high concentration Ge doped CZ-Si single crystals can be determined by FTIR.

关键词： SiGe single crystal Ge content FTIR czochralski method

Experiment and numerical simulation of melt convection and oxygen distribution in 400-mm czochralski silicon crystal growth

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Rare Metals 2017年第2期36卷 134-141页

作者： Ran Teng Yang Li Bin Cui Qing Chang Qing-Hua Xiao Guo-Hu Zhang National Engineering Research Center for Semiconductor Materials Beijing 100088China Semiconductor Materials Co. LtdGeneral Research Institute for Nonferrous MetalsBeijing 100088China

Single-crystalline silicon materials with large dimensions have been widely used as assemblies in plasma silicon etching ***,information about large-diameter low-cost preparation technology has not been sufficiently *** this paper,it was focused on the preparation of 400-mm silicon（100） crystal lightly doped with boron from *** *** uniformity and oxygen concentration of the silicon crystal were investigated by direct-current（DC） four-point probes method and Fourier transform infrared spectroscopy（FTIR）,*** global heat transfer,melt flow and oxygen distribution were calculated by finite element method（FEM）.The results show that *** zones can replace conventional 32 *** to grow 400-mm-diameter silicon single *** change in crucible diameter can save energy,reduce cost and improve *** trend of oxygen distribution obtained in calculations is in good agreement with experimental *** present model can well predict the 400-mm-diameter silicon crystal growth and is essential for the optimization of furnace design and process condition.

关键词： Silicon crystal preparation Computer simulation czochralski method Heat transfer Melt flow Oxygen distribution

Structure of BaGd_2(MoO_4)_4 Crystal

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Chinese Journal of Structural Chemistry 2007年第3期26卷 328-332页

作者： ZHAO Dan LIN Zhou-Bin WANG Guo-Fu State Key Laboratory of Structural Chemistry Fujian Institute of Research on theStructure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

The title compound belongs to monoclinic, space group C2/c with a = 5.2694（1）, b = 12.6659（4）, c = 19.4108（2） A,β= 91.504（2）°, V = 1295.06（5） A^3, Z = 4 and Dc= 5.599 g/cm^3. The structure of BaGd2（MoO4）4 contains a MoO4 tetrahedron, a distorted GdO8 polyhedron, and Ba^2＋ ions in a tenfold coordination. The GdO8 polyhedra are linked together through edge-sharing to give a two-dimensional Gd layer. The MoO4 tetrahedra connected to the Gd atoms are capped up and down the Gd layer through common oxygen apices, thus-forming a new Gd-Mo layer. Finally, the Gd-Mo layers are held together through bridging BaO10 polyhedra to form a three-dimensional framework. Since the Ba-μ3-O bond has a large average distance of 2.888 A, this structural characteristic will result in a cleavage along the （001） plane.

关键词： czochralski method BaGd2(MoO4)4 crystal

Raman Spectra of Nd:La3Ga5SiO14 and Nd:La3Ga5.5Ta0.5O14 Crystals

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Chinese Journal of Structural Chemistry 2016年第11期35卷 1673-1678页

作者：张娜娜王继扬潘晓茹宋明君 Clenilton Costa dos Santos Ilde Guedes da Guedesa College of Chemistry & Chemical and Environmental Engineering Weifang University State Key Laboratory of Crystal Materials Shandong University Departamento de Física CCETUniversidade Federal do Maranh?o Departamento de Física Universidade Federal do CearáCampus do Pici

Single crystals of Nd：La3Ga5SiO14 （NLGS） and Nd：La3Ga5.5Ta0.5O14 （NLGT） were grown by czochralski method. Both crystals exhibit a langasite structure （space group D32 （P321） with Z = 1）, whose general formula is A3BC2D3O14, where A, B, C and D represent the dodecahedral, octahedral and tetrahedral positions, respectively. The adding of low content of Nd does not change the crystal structure. Although they are isostructural, the distribution of atoms among the symmetric sites is different. While NLGT exhibits a perfect orderly structure, NLGS exhibits an intrinsically disordered structure due to the random distribution of Ga and Si atoms at the C3（2） symmetry sites. To understand what changes occur in the phonon distribution when Ta replaces Si, we recorded and analyzed room temperature polarized Raman spectra. We observe 8A1＋18E modes for NLGS and 10A1＋13E for NLGT crystals. When Si is substituted by Ta, we observe that the wavenumber of some modes related to vibrations involving Ga and O atoms decreases. This agrees with the fact that the Ga–O bonds are shorter in NLGS than in NLGT.

关键词： czochralski method langasite structure Raman scattering piezoelectric