Journal of Crystal Growth最新文献_第4页

Simulation of temperature and convection field of diamond large single crystal growth with different catalyst systems 不同催化剂体系下金刚石大单晶生长的温度场和对流场模拟

IF 2 4区材料科学 Q3 CRYSTALLOGRAPHY

Journal of Crystal Growth

Pub Date : 2025-11-13 DOI: 10.1016/j.jcrysgro.2025.128419

Fuming Deng , Ziyi Liu , Wenli Deng , Xiaozhou Chen , Liqiu Huang , Xiaotian Xing , Houzhen Chen , Junzhe Yu , Can Li

Diamond is the hardest and most stable crystal in nature (lattice constant 3.567 Å, bond length 1.54 Å) formed by carbon atoms bonded by SP³ and large-size diamond single crystals have a wide range of applications, which is one of the research hotspots of superhard materials nowadays. This study focuses on the high-pressure high-temperature (HPHT) method to produce large-size (≥15 ct) single crystals using an optimized China-type apparatus (CHPA). The effects of different catalyst melts on crystal growth rates were investigated by simulating the temperature field and convection field within the composite cavity—key factors influencing crystal growth rates—using the finite element method (FEM) and the Finite Volume Method (FVM).

The research results indicate that using the high-temperature, high-pressure method to produce synthetic diamonds with Fe-Co and Fe-Co-C catalysts can make the temperature distribution in the synthesis chamber more uniform and the carbon convection rate more stable, and provide “visualization” of the growth process for high-temperature, high-pressure synthetic diamonds. It can also adapt to the production needs of diamonds of different shapes, providing new ideas for resolving the conflict between speed and quality in the production of large, high-quality diamonds.

金刚石是自然界中最坚硬、最稳定的晶体（晶格常数3.567 Å，键长1.54 Å），由碳原子通过SP3键合形成，大尺寸金刚石单晶具有广泛的应用，是当今超硬材料的研究热点之一。本文主要研究了高压高温（HPHT）法制备大尺寸（≥15 ct）单晶的方法。采用有限元法（FEM）和有限体积法（FVM）模拟影响晶体生长速率的关键因素——复合材料腔内的温度场和对流场，研究了不同催化剂熔体对晶体生长速率的影响。研究结果表明，采用高温高压方法制备Fe-Co和Fe-Co- c催化剂合成金刚石，可以使合成室内温度分布更加均匀，碳对流速率更加稳定，为高温高压合成金刚石的生长过程提供“可视化”。它还能适应不同形状钻石的生产需要，为解决大质量钻石生产中速度与质量的矛盾提供了新的思路。

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引用次数: 0

Thermally driven growth of MAPbBr3 single crystals MAPbBr3单晶的热驱动生长

IF 2 4区材料科学 Q3 CRYSTALLOGRAPHY

Journal of Crystal Growth

Pub Date : 2025-11-09 DOI: 10.1016/j.jcrysgro.2025.128410

Tzu-Lung Chang , Yu-Li Hsieh , Hseuh-Hsing Hung , Jau-Wern Chiou , Hui-Huang Hsieh

Methylammonium lead tribromide (MAPbBr₃) is a promising material that can be utilized in optoelectronic devices due to its excellent photon-electron conversion efficiency. To prevent the recombination of photogenerated electron-hole pairs during current transport, a high-quality single crystal with minimal defects is necessary. We have developed a localized thermal drive inverse temperature crystallization (LTDITC) method for MAPbBr₃ single crystal growth. The temperature distribution of the localized heat crystal growth setup was monitored with a thermal imager in specific areas during the crystal growth process. The presence of a single-phase diffraction peak and the narrow full width at half maximum (FWHM) of the (200) peak in the X-ray diffraction (XRD) pattern indicates that the crystal grown by the new LTDITC method is a high-quality single crystal. A comparison of the (200) peak FWHM for the grown crystal with that of crystals produced by the traditional oil bath method indicates a much lower defect density in the new crystal. Photoluminescence (PL) and Raman spectra reveal a narrow peak at 545 nm and 327 cm⁻¹, respectively, indicating superior crystalline quality. The new crystal’s bandgap is 2.19 eV, which is determined by a sharp UV–Vis absorption edge. Additionally, space charge limited current (SCLC) calculations reveal a low trap-state density of 6.5 × 10⁹ cm⁻³ and a carrier mobility of 64 cm² V⁻¹ s⁻¹, further confirming its exceptional optoelectronic properties.

三溴化甲基铅铵（MAPbBr3）由于其优异的光电子转换效率，是一种很有前途的光电子器件材料。为了防止光生电子-空穴对在电流输运过程中的复合，需要一种缺陷最小的高质量单晶。我们开发了一种局部热驱动反温度结晶（LTDITC）方法来生长MAPbBr3单晶。利用热成像仪对晶体生长过程中特定区域局部热晶体生长装置的温度分布进行了监测。x射线衍射（XRD）图中出现了一个单相衍射峰，（200）峰半峰全宽较窄，表明该方法生长的晶体是一种高质量的单晶。通过与传统油浴法制备的晶体的（200）峰FWHM比较，发现新晶体的缺陷密度要低得多。光致发光（PL）和拉曼光谱分别在545 nm和327 cm−1处显示出窄峰，表明优越的晶体质量。新晶体的带隙为2.19 eV，这是由尖锐的UV-Vis吸收边决定的。此外，空间电荷限制电流（SCLC）计算显示其低阱态密度为6.5 × 109 cm−3，载流子迁移率为64 cm2 V−1 s−1，进一步证实了其卓越的光电特性。

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引用次数: 0

Numerical simulation of induction skull melting process of gallium oxide compounds 氧化镓化合物感应熔壳过程的数值模拟

IF 2 4区材料科学 Q3 CRYSTALLOGRAPHY

Journal of Crystal Growth

Pub Date : 2025-11-08 DOI: 10.1016/j.jcrysgro.2025.128409

Yanshen Wang , Mingzhi Zhu , Yuan Liu

As a typical wide-bandgap semiconductor, Gallium oxide (Ga₂O₃) crystal is an ideal substrate material for power and deep-ultraviolet devices. The traditional growth process for Ga₂O₃ single crystal requires extremely expensive Ir crucibles, which greatly hinders its application and development. This article aims to develop the induction skull melting (ISM) process for high-purity melting and single crystal growth of Ga₂O₃, without iridium crucible. Based on the multi-field coupling model, a systematical simulation was conducted to study the effect of frequency and magnitude of the induction power on the temperature evolution, the fluid flowing pattern, the meniscus shape, and the skull morphology. Simultaneously, the ignition and solidification process were also displayed. There is a good agreement between the theoretical calculations and the experimental results. The studied results demonstrate that the ISM process has the potential for the melting and growth of Ga₂O₃ single crystal.

作为一种典型的宽禁带半导体，氧化镓（Ga2O3）晶体是电力和深紫外器件的理想衬底材料。传统的Ga2O3单晶生长工艺需要极其昂贵的Ir坩埚，这极大地阻碍了其应用和发展。本文的目的是在没有铱坩埚的情况下，开发高纯度Ga2O3熔炼和单晶生长的感应颅骨熔炼（ISM）工艺。基于多场耦合模型，系统仿真研究了感应功率频率和大小对温度演变、流体流动模式、半月板形状和颅骨形态的影响。同时，还展示了材料的点火和凝固过程。理论计算与实验结果吻合较好。研究结果表明，ISM工艺具有熔化和生长Ga2O3单晶的潜力。

引用次数: 0

Crystal growth and spectroscopic performance of CdMgTe radiation detector CdMgTe辐射探测器的晶体生长和光谱性能

IF 2 4区材料科学 Q3 CRYSTALLOGRAPHY

Journal of Crystal Growth

Pub Date : 2025-11-07 DOI: 10.1016/j.jcrysgro.2025.128407

Henry Chen , Susan Kutcher , Cory Rosemier , Julie Wen , Sudhir Trivedi

Although cadmium zinc telluride (CZT) is currently the material of choice for high resolution room temperature nuclear radiation detection, it has several drawbacks, making it very difficult to produce in large volumes and at low cost simultaneously. In this work, we introduce cadmium magnesium telluride (CdMgTe) as a promising alternative room temperature semiconductor detector that solves these issues. The advantages of CdMgTe over CZT, the growth, material characterization of CdMgTe, and ultimately its nuclear radiation response are studied and reported here, where energy resolution of single channel form was as good as 1.5 % at 662 keV gamma without any signal correction.

虽然碲化镉锌（CZT）是目前高分辨率室温核辐射检测的首选材料，但它有几个缺点，使得它很难同时大批量低成本生产。在这项工作中，我们介绍了碲化镉镁（CdMgTe）作为一种有前途的室温半导体探测器，解决了这些问题。CdMgTe相对于CZT的优势、CdMgTe的生长、材料特性以及最终的核辐射响应在这里进行了研究和报道，其中单通道形式的能量分辨率高达1.5%，在662 keV伽马下没有任何信号校正。

引用次数: 0

Discovery of a new magnesium iron boride Mg4Fe1.1B13.9 in the Mg-Fe-B-N system 在Mg-Fe-B-N体系中发现一种新的镁铁硼化物Mg4Fe1.1B13.9

IF 2 4区材料科学 Q3 CRYSTALLOGRAPHY

Journal of Crystal Growth

Pub Date : 2025-11-06 DOI: 10.1016/j.jcrysgro.2025.128406

N.D. Zhigadlo

A new boron-rich ternary phase, Mg₄Fe_1.1B_13.9, was discovered in the Mg-Fe-B-N quaternary system. This novel phase appears in the form of plate-like shaped crystals formed on the surface of Fe-substituted MgB₂ during high-pressure, high-temperature (HPHT) solution growth at 3 GPa and 1960 °C. Mg₄Fe_1.1B_13.9 crystallizes in an orthorhombic structure with space group Pnam (No. 62) and lattice parameters a = 10.95(2) Å, b = 7.07(1) Å, and c = 8.72(1) Å. Structural refinement reveals a layered architecture composed of alternating layers of Mg-Fe and boron, with boron atoms forming 5-, 6-, and 7-membered ring motifs. A structural comparison indicates that Mg₄Fe_1.1B_13.9 is closely related to the Y₂ReB₆-type borides. This discovery highlights the effectiveness of the HPHT synthesis in accessing new, complex boron-rich phases. As research in the binary Mg-B system approaches saturation, the identification of Mg₄Fe_1.1B_13.9 offers new insights into the formation of phases in the Mg-Fe-B-N system. This paves the way for the guided synthesis of novel borides with unique properties in other multicomponent systems.

在Mg-Fe-B-N四元体系中发现了一种新的富硼三元相Mg4Fe1.1B13.9。在3gpa和1960℃的高压、高温（HPHT）溶液生长过程中，这种新相以板状晶体的形式出现在fe取代MgB2表面。Mg4Fe1.1B13.9为正交晶型，晶格参数为a = 10.95(2) Å， b = 7.07(1) Å， c = 8.72(1) Å。结构细化揭示了由Mg-Fe和硼交替层组成的层状结构，硼原子形成5-，6-和7元环基序。结构比较表明，Mg4Fe1.1B13.9与y2reb6型硼化物密切相关。这一发现突出了HPHT合成在获取新的、复杂的富硼相方面的有效性。随着对二元Mg-B体系的研究接近饱和，Mg4Fe1.1B13.9的鉴定为Mg-Fe-B-N体系中相的形成提供了新的见解。这为在其他多组分体系中定向合成具有独特性能的新型硼化物铺平了道路。

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引用次数: 0

Growth of ultra-clean oxide single crystals of the altermagnet candidate RuO2 交替磁体候选材料RuO2超净氧化物单晶的生长

IF 2 4区材料科学 Q3 CRYSTALLOGRAPHY

Journal of Crystal Growth

Pub Date : 2025-11-05 DOI: 10.1016/j.jcrysgro.2025.128405

Shubhankar Paul , Giordano Mattoni , Hisakazu Matsuki , Thomas Johnson , Chanchal Sow , Shingo Yonezawa , Yoshiteru Maeno

We report the details of the growth of ultra-clean oxide single crystals of RuO₂, a candidate material for altermagnetism. By using a necking-structure crystal-growth tube and finely tuning the conditions of the sublimation transport method, we demonstrate a systematic control of the crystal morphology. We obtained mainly three kinds of morphologies: thick plate-like crystals up to

10 \times 5 \times 2 {mm}^{3}

with a large (101) facet, rhombohedral columnar crystals elongating along the [001] direction, and fiber and needle crystals of length up to 8 mm. These crystals show residual resistivity of about

30 n Ω cm

and a residual resistivity ratio (RRR) up to 1200, substantially higher than previous reports. We extended the resistivity modeling and resolved the discrepancy between Debye temperatures from specific heat and resistivity. These ultra-clean oxide crystals with much higher RRR than other recent studies lead us to make a decisive conclusion that the intrinsic ground state of bulk RuO₂ is paramagnetic.

本文报道了RuO2超净氧化单晶的生长过程。通过使用颈状结构的晶体生长管和微调升华传输方法的条件，我们证明了对晶体形态的系统控制。我们主要获得了三种形态：厚度达10×5×2mm3的大（101）面厚板状晶体，沿[001]方向拉长的菱形柱状晶体，以及长度达8mm的纤维和针状晶体。这些晶体的剩余电阻率约为30nΩcm，剩余电阻率比（RRR）高达1200，大大高于以前的报道。我们扩展了电阻率模型，并从比热和电阻率的角度解决了德拜温度的差异。这些超干净的氧化物晶体具有比其他近期研究高得多的RRR，这使我们得出一个决定性的结论，即大块RuO2的本征基态是顺磁性的。

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引用次数: 0

Fabrication of polarity-inverted AlN using a single high-temperature face-to-face annealing 单次高温面对面退火制备极性反转AlN

IF 2 4区材料科学 Q3 CRYSTALLOGRAPHY

Journal of Crystal Growth

Pub Date : 2025-11-05 DOI: 10.1016/j.jcrysgro.2025.128408

Kanako Shojiki , Hideto Miyake

To reduce fabrication time, a method for fabricating a vertical-polarity-inverted AlN structure on a sapphire substrate from multilayered sputtered AlN (Sp-AlN) using a single face-to-face annealing (FFA) step is desirable to reduce the fabrication time. In this study, a single FFA was performed on bilayer Sp-AlN structures fabricated using two approaches: switching the sputtering target and introducing a thin Al₂O₃ layer. However, in a stacked structure of Sp-AlN deposited using an Al metal target (Sp-AlN(Al target))/Sp-AlN deposited using a sintered AlN target (Sp-AlN(AlN target)) on sapphire, the results after a single FFA indicated that the oxygen concentration supplied by the sintered AlN target was insufficient for polarity inversion at the intended position. Therefore, Al₂O₃ was introduced as a high-oxygen-concentration layers. Consequently, after a single FFA step, the Sp-AlN(Al target)/Al₂O₃/Sp-AlN(Al target)/sapphire structure, with an Al₂O₃ thickness of more than 2 nm, exhibited a vertical-polarity-inverted AlN structure (Al-polar AlN/N-polar AlN/sapphire) with polarity inversion at the desired positions. Therefore, this route is promising for fabricating vertical-polarity-inverted AlN structures with shorter fabrication times.

为了缩短制备时间，需要采用单步面对面退火（FFA）的方法，在蓝宝石衬底上用多层溅射AlN （Sp-AlN）制备垂直极性倒置AlN结构，以缩短制备时间。在本研究中，采用切换溅射靶和引入薄Al2O3层两种方法对双层Sp-AlN结构进行了单一FFA。然而，在使用Al金属靶材（Sp-AlN(Al target)）沉积Sp-AlN /使用烧结AlN靶材（Sp-AlN(AlN target)）沉积Sp-AlN在蓝宝石上的堆叠结构中，单次FFA后的结果表明，烧结AlN靶材（Sp-AlN(AlN target)）提供的氧浓度不足以在预定位置进行极性反转。因此，Al2O3作为高氧浓度层被引入。结果表明，经过一次FFA处理后，当Al2O3厚度大于2 nm时，Sp-AlN（Al靶）/Al2O3/Sp-AlN（Al靶）/蓝宝石结构呈现出垂直极性反转AlN结构（Al-极性AlN/ n -极性AlN/蓝宝石），并在所需位置发生极性反转。因此，该方法有望以更短的制造时间制造垂直极性反转AlN结构。

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引用次数: 0

Confined nanocrystallization of anthranilic acid in a mesoporous zeolite matrix 邻氨基苯甲酸在介孔沸石基质中的受限纳米晶化

IF 2 4区材料科学 Q3 CRYSTALLOGRAPHY

Journal of Crystal Growth

Pub Date : 2025-11-04 DOI: 10.1016/j.jcrysgro.2025.128394

K.M.M. Bimsara Chandrasekera , Francesco Civati , Nadeesh M. Adassooriya

This study explores the confined crystallization of anthranilic acid, an active pharmaceutical ingredient (API), within a mesoporous zeolite matrix, emphasizing the impact of nanoscale confinement on crystal size, morphology, and polymorphic outcomes. By leveraging a suite of characterization techniques—including Powder X-ray Diffraction (PXRD), Differential Scanning Calorimetry (DSC), Scanning and Transmission Electron Microscopy (SEM, TEM), and Fourier Transform Infrared (FTIR) Spectroscopy—we elucidate the structural transformations associated with crystallization under nanoconfinement. TEM imaging reveals the formation of needle-like crystals (∼20 nm in diameter) aligned within the zeolite’s 3D pore structure, indicating directional crystal growth constrained by the matrix. DSC analysis shows a depression in melting points relative to the bulk (from 147 ℃ to 143 ℃ and 144 ℃ for acetonitrile- and ethanol-mediated crystallization, respectively), accompanied by broadened endothermic peaks—hallmarks of size and confinement-induced effects. PXRD and FTIR confirm solvent-dependent polymorphic forms (Form I and Form II), underscoring the dual role of confinement and solvent environment in directing polymorphic selection. These findings highlight confined crystallization as a powerful strategy for modulating the physicochemical properties of APIs, offering promising implications for enhancing drug stability, solubility, and delivery efficiency.

本研究探索了氨基苯甲酸（一种活性药物成分）在介孔沸石基质中的受限结晶，强调了纳米级限制对晶体尺寸、形态和多态结果的影响。通过利用一系列表征技术-包括粉末x射线衍射（PXRD），差示扫描量热法（DSC），扫描和透射电子显微镜（SEM， TEM）和傅里叶变换红外（FTIR）光谱-我们阐明了纳米约束下与结晶相关的结构转变。透射电镜成像显示，在沸石的三维孔隙结构中形成针状晶体（直径约20 nm），表明定向晶体生长受到基体的约束。DSC分析显示熔点相对于体积有所下降（乙腈和乙醇介导结晶分别从147℃降至143℃和144℃），并伴有变宽的吸热峰，这是尺寸和约束效应的标志。PXRD和FTIR证实了溶剂依赖性的多晶形式（Form I和Form II），强调了约束和溶剂环境在指导多晶选择中的双重作用。这些发现强调了限制结晶作为调节原料药物理化学性质的有力策略，为提高药物稳定性、溶解度和递送效率提供了有希望的意义。

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引用次数: 0

Numerical simulation study on the influence of process parameters of a horizontal CVD furnace on the deposition thickness and uniformity of ZnS 卧式气相沉积炉工艺参数对ZnS沉积厚度和均匀性影响的数值模拟研究

IF 2 4区材料科学 Q3 CRYSTALLOGRAPHY

Journal of Crystal Growth

Pub Date : 2025-11-01 DOI: 10.1016/j.jcrysgro.2025.128393

Yunhao Yang , Qiangguo Deng , Wenyuan Mao , Sushan Yuan , Yong Zhou , Pingyang Yu

To further investigate the effects of different process parameters on the chemical vapor deposition (CVD) synthesis of zinc sulfide, this study employed Fluent software to conduct numerical simulations of the ZnS synthesis process in a horizontal CVD furnace. Four experimental sets with varying process parameters were established for comparative analysis and validation. The results demonstrated that the maximum deviation in deposition thickness remained below 20 %, confirming the feasibility of numerical simulation. Based on this, the effects of process parameters such as temperature, pressure, and flow ratio on deposition thickness and uniformity were further investigated. The results revealed that within the temperature range of 620 °C to 655 °C, deposition thickness increased with rising temperature while uniformity correspondingly decreased; When pressure increased from 4000 Pa to 5000 Pa, both deposition thickness and uniformity exhibited a decreasing trend; As the H₂S/Zn flow ratio increased, deposition thickness showed a corresponding increase, while uniformity demonstrated minimal variation, with only slight improvement observed within the 0.2–0.5 ratio range; The Ar/H₂S flow ratio exhibited no significant effect on either deposition thickness or uniformity, with both parameters showing only a slight increasing trend within the 4–6 range; The results of this study provide a theoretical basis for optimizing the process parameters of horizontal CVD furnaces to enhance the deposition thickness and uniformity of ZnS.

为了进一步研究不同工艺参数对化学气相沉积（CVD）合成硫化锌的影响，本研究利用Fluent软件对卧式CVD炉中ZnS合成过程进行了数值模拟。建立了4套不同工艺参数的实验装置进行对比分析和验证。结果表明，沉积厚度的最大偏差保持在20%以下，证实了数值模拟的可行性。在此基础上，进一步研究了温度、压力、流量比等工艺参数对沉积厚度和均匀性的影响。结果表明：在620 ~ 655℃温度范围内，沉积厚度随温度升高而增大，均匀性相应降低；当压力从4000 Pa增加到5000 Pa时，沉积厚度和均匀性均呈下降趋势；随着H2S/Zn流动比的增加，沉积厚度相应增加，均匀性变化不大，在0.2 ~ 0.5流动比范围内仅略有改善；Ar/H2S流量比对沉积厚度和均匀性均无显著影响，在4 ~ 6范围内均呈轻微增加趋势；研究结果为优化卧式气相沉积炉工艺参数以提高ZnS的沉积厚度和均匀性提供了理论依据。

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引用次数: 0

Enhanced IR transmittance of CZT substrates: Surface processing and Cd-saturated annealing 提高CZT衬底的红外透射率：表面处理和饱和镉退火

IF 2 4区材料科学 Q3 CRYSTALLOGRAPHY

Journal of Crystal Growth

Pub Date : 2025-11-01 DOI: 10.1016/j.jcrysgro.2025.128395

Shangshu Li , Xiaolu Xiong , Chao Xu , Changhe Zhou

The IR transmission behavior of Cd_1-_xZn_xTe (CZT) slices can provide useful information about inclusion/precipitate feature, stoichiometry and free carriers. High infrared (IR) transmittance is essential for the application of CZT in infrared focal plane arrays (IRFPA). The IR transmittance features of the CZT slices with different surface states are analyzed, and the indicator T₆₂₅ is used to assess whether the slices should be annealed or not. The preprocessed CZT slices with rough surfaces and T₆₂₅ < 45 % are annealed under Cd-saturated atmosphere, and results demonstrate that IR transmittance improvement is insignificant either by increasing annealing time or temperature. Furthermore, the (111) Cd and (111) Te surfaces are respectively ground (to obtain smooth surfaces) and annealed. The result shows the IR transmittance improvement of slices ground on (111) Cd surface is more obvious compared with slices ground on (111) Te surface. Density functional theory (DFT) calculations were also employed to investigate the reaction mechanism between molecular oxygen and CdTe, and the theoretical calculation results indicate that (111) Te surface is more easily oxidized than (111) Cd surface. The experimental and theoretical results demonstrate the presence of oxidation layer can account for the ineffective IR transmittance improvement. Additionally, a cost-effective CZT substrate processing is proposed in this study.

Cd1-xZnxTe （CZT）薄片的红外透射行为可以提供有关包裹/沉淀特征、化学计量学和自由载流子的有用信息。高红外透过率是CZT在红外焦平面阵列（IRFPA）中应用的必要条件。分析了不同表面状态CZT薄片的红外透射率特征，并利用T625指标评价了薄片是否需要退火。对表面粗糙、T625 <； 45%的经预处理的CZT薄片在饱和镉气氛下进行退火，结果表明，增加退火时间和温度对其红外透射率的提高都不显著。此外，（111）Cd和（111）Te表面分别进行研磨（以获得光滑表面）和退火。结果表明，（111）Cd表面的薄片比（111）Te表面的薄片红外透过率提高更明显。采用密度泛函理论（DFT）研究了分子氧与CdTe的反应机理，理论计算结果表明（111）Te表面比（111）Cd表面更容易被氧化。实验和理论结果表明，氧化层的存在是导致红外透过率提高效果不明显的原因。此外，本研究还提出了一种具有成本效益的CZT衬底加工方法。

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引用次数: 0