Journal of Crystal Growth最新文献

{"title":"Comparative analysis of machine learning approaches for predicting and interpreting Cz-sapphire growth","authors":"Xia Tang,&nbsp;Milena Petković,&nbsp;Gagan-Kumar Chappa,&nbsp;Lucas Vieira,&nbsp;Natasha Dropka","doi":"10.1016/j.jcrysgro.2025.128185","DOIUrl":"10.1016/j.jcrysgro.2025.128185","url":null,"abstract":"<div><div>This study evaluates four machine learning (ML) “white-box” methods − Decision Trees, Linear Regression, Python Symbolic Regression (PySR), and Sure Independence Screening and Sparsity Operation (SISSO) − and five “gray-box” methods − Gradient Boosting, XGBoost, Support Vector Machines (SVM), Gaussian Processes, and Random Forests − for analyzing data from the Cz-sapphire crystal growth process. The objective is to develop a model that achieves a balance between high predictive accuracy and interpretability in this small-data domain.</div><div>Twelve input variables − including process parameters, sapphire optical properties, and furnace geometry parameters − were analyzed in relation to five output variables: heating power, interface deflection, temperature gradients averaged at the solid/liquid interface and symmetry axis, and v/G. Using 500 data tuples from CFD simulations, the results highlighted significant performance differences across the models. SVM demonstrated superior performance in predicting temperature gradients, XGBoost excelled in interface deflection predictions, and Gradient Boosting was most effective for v/G. SISSO, known for its high interpretability, performed best in predicting heating power, particularly in cases where nonlinear noise was less pronounced.</div><div>The best performing models for each output generated explicit equations that relate inputs to outputs, feature importance plots, and 3D plots illustrating relationships within the 17-dimensional space. These findings offer theoretical insights for optimizing the Cz-sapphire crystal growth process and design.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"664 ","pages":"Article 128185"},"PeriodicalIF":1.7,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143859482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to “New pentaborates for pyrolytic boron nitride” [J. Cryst. Growth 660 (2025) 128160]","authors":"Bo Li ,&nbsp;Weilong Wu ,&nbsp;Zifeng Niu ,&nbsp;Lu Meng ,&nbsp;Haoran Chen ,&nbsp;Shijie Ma ,&nbsp;Jun Zhang ,&nbsp;Wei Tian ,&nbsp;Jahangeer Ahmed ,&nbsp;Chengchun Tang ,&nbsp;Yanming Xue","doi":"10.1016/j.jcrysgro.2025.128176","DOIUrl":"10.1016/j.jcrysgro.2025.128176","url":null,"abstract":"","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"661 ","pages":"Article 128176"},"PeriodicalIF":1.7,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143858999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of As2 flux on the growth of InAs/InGaAs dot-in-well structure by molecular beam epitaxy","authors":"Ruo-Tao Liu ,&nbsp;Kun Wang ,&nbsp;Jian-Chu Wu ,&nbsp;Chen Yang ,&nbsp;Hua Huang ,&nbsp;Zheng-He Zhu ,&nbsp;Han Wang ,&nbsp;Chun-Fang Cao ,&nbsp;Jin Yang ,&nbsp;An-Tian Du ,&nbsp;Qian Gong","doi":"10.1016/j.jcrysgro.2025.128193","DOIUrl":"10.1016/j.jcrysgro.2025.128193","url":null,"abstract":"<div><div>This study systematically investigates the growth of InAs/InGaAs dot-in-well (DWELL) structure with a wide range of As₂ flux employed during the growth of InAs dot layer. It is found that As₂ flux plays a very important role in the growth of the DWELL structure, which fundamentally affects the migration length and the desorption rate of In atoms. A non-monotonic variation in the density of InAs quantum dots (QDs) has been observed with varying As₂ flux. In addition, the average width and height of QDs also depends on the As₂ flux. The photoluminescence (PL) peak intensity from the DWELL structure exhibits a remarkable relationship with the As₂ flux, where a maximum intensity enhancement of 90 % was achieved by using the optimized As₂ flux. A total redshift of 58 nm in the peak emission wavelength has been observed within the As₂ flux range studied. Moreover, it has been the first experimental evidence for a distinctive phenomenon that the QDs in the DWELL structure might not be fully capped by the InGaAs layer when the QDs were grown with low As₂ fluxes. Therefore, decomposition of the uncapped portion of QD may occur, resulting in a large blueshift of the PL emission peak from the DWELL structure.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"663 ","pages":"Article 128193"},"PeriodicalIF":1.7,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143823524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pathway and control of oxygen transport in the melt during single crystal silicon growth by continuous-feeding Czochralski method","authors":"Jiancheng Li ,&nbsp;Junlei Wang ,&nbsp;Zeqi Zhong ,&nbsp;Zaoyang Li ,&nbsp;Yong Wen ,&nbsp;Lei Wang ,&nbsp;Lijun Liu","doi":"10.1016/j.jcrysgro.2025.128183","DOIUrl":"10.1016/j.jcrysgro.2025.128183","url":null,"abstract":"<div><div>The continuous-feeding Czochralski (CCz) method is regarded as the most advanced technology for the growth of large-sized single crystal silicon with a uniform axial distribution of impurities. However, the use of double quartz crucibles in this method results in a high concentration of oxygen impurities in the crystal, which has become a technical bottleneck for the widespread adoption of this technology. In this paper, a series of numerical simulations were carried out firstly. It was found that the oxygen transported to the melt-crystal (m-c) interface mainly comes from the dissolution at the crucible wall of growth zone (inside the inner crucible). Furthermore, the diffusion path of oxygen in the melt was creatively elucidated, which has enabled the oxygen transport pathway to be identified. Based on this, the oxygen content of single crystal silicon was reduced by enhancing the forced convection induced by crucible rotation, and the result was verified experimentally.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"662 ","pages":"Article 128183"},"PeriodicalIF":1.7,"publicationDate":"2025-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143815280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The critical role of hydrocarbon source and growth optimization for high-quality thick 4H-SiC epitaxial layers","authors":"Misagh Ghezellou,&nbsp;Jawad Ul-Hassan","doi":"10.1016/j.jcrysgro.2025.128165","DOIUrl":"10.1016/j.jcrysgro.2025.128165","url":null,"abstract":"<div><div>The development of ultra-high power electronic devices based on 4H-SiC relies on the growth of high-quality thick epitaxial layers. Chloride-based chemical vapor deposition is preferred for this purpose, and in this study we show that optimizing the process also requires a careful selection of hydrocarbons as the carbon source. Propane, a common precursor, limits control over the C/Si ratio at high growth rates, leading to defects and even loss of crystallinity. In contrast, methane offers a wider window for C/Si ratio adjustment, enabling further optimization of the epitaxial growth process. Using methane, an optimal growth rate of <span><math><mrow><mn>25</mn><mspace></mspace><mi>μ</mi><mi>m</mi></mrow></math></span>/h is identified at which the minority carrier lifetime is maximized. Additionally, a saturation limit for minority carrier lifetime is observed in layers exceeding a thickness of <span><math><mo>∼</mo></math></span> <span><math><mrow><mn>100</mn><mspace></mspace><mi>μ</mi><mi>m</mi></mrow></math></span>. It is also shown that, although the formation of characteristic surface morphological defects is inevitable, their severity can be controlled by adding additional HCl or increasing the growth rate; however, at a cost of reduced minority carrier lifetime. The growth of <span><math><mrow><mn>125</mn><mspace></mspace><mi>μ</mi><mi>m</mi></mrow></math></span> thick epitaxial wafers with methane and propane demonstrates the advantage of using methane as the carbon source. This is evidenced by a smoother surface, better doping uniformity, and nearly double the minority carrier lifetime compared to the propane-grown wafer. These findings highlight the benefits of methane in growing thick 4H-SiC epitaxial layers for high-power devices.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"661 ","pages":"Article 128165"},"PeriodicalIF":1.7,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143791093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling solution concentration in cooling crystallization using an ultrasonic probe and image monitoring","authors":"Junjie Li ,&nbsp;Yiting Xiao ,&nbsp;Bo Kong","doi":"10.1016/j.jcrysgro.2025.128178","DOIUrl":"10.1016/j.jcrysgro.2025.128178","url":null,"abstract":"<div><div>Supersaturation during the crystallization process has been a primary focus of research for many years. The ability to measure solution concentration in situ is essential for improving our understanding and control of crystallization. In this paper, we present a solution concentration model for dynamic cooling crystallization based on ultrasonic speed, using L-glutamic acid (LGA) as the case study. The speed of sound and temperature changes of the solution were recorded during the cooling crystallization process. The collected data was categorized into the undersaturated zone (USZ) and the metastable zone (MSZ) for model development. To accurately distinguish between these intervals, a noninvasive imaging device was employed to capture the exact moment of crystal formation. Our results demonstrate the feasibility of using an ultrasonic probe for in situ monitoring of concentration changes during cooling crystallization. Furthermore, an experiment involving LGA cooling crystallization was carried out to validate the model’s sensitivity in detecting the crystallization process.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"662 ","pages":"Article 128178"},"PeriodicalIF":1.7,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143792246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cost-effective, hydride-free aqueous synthesis of CdTe quantum dots enabled by using ammonia as the reducing agent","authors":"Van-Thao Ta ,&nbsp;Duy-Khanh Nguyen ,&nbsp;Xuan-Bach Nguyen ,&nbsp;Phuong-Nam Nguyen ,&nbsp;Sinh-Hung Nguyen ,&nbsp;Xuan-Dung Mai","doi":"10.1016/j.jcrysgro.2025.128182","DOIUrl":"10.1016/j.jcrysgro.2025.128182","url":null,"abstract":"<div><div>The development of a simple, cost-effective, and green method to synthesize CdTe quantum dots (QDs), which are a key nanomaterial in sensing, bioimaging, and immunofluorescence analysis is highly desirable. In this study, we used ammonia in lieu of common hydride reductant to synthesize CdTe QDs by simple refluxing aqueous solutions of cadmium salt, sodium tellurite, and 3-mercaptopropionic acid (MPA). The obtained CdTe QDs were characterized by absorption and photoluminescent spectroscopies, X-ray diffraction (XRD), and transmission electron microscope (TEM). The absorption window and the emission color of QDs were facile controlled over the green–red range by varying the refluxing time. As the QD size increased the crystal structure transformed from CdTe to a CdTeS alloyed form. The results demonstrated herein suggest a cost-effective method for production of CdTe QDs.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"661 ","pages":"Article 128182"},"PeriodicalIF":1.7,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143785150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Low and high temperature magnetic properties of MgFe2O4 nanoparticles synthesized by a simple egg white albumin route","authors":"Annrose Sunny ,&nbsp;Kasarapu Venkataramana ,&nbsp;Y. Ranjith Kumar ,&nbsp;M. Vasundhara","doi":"10.1016/j.jcrysgro.2025.128174","DOIUrl":"10.1016/j.jcrysgro.2025.128174","url":null,"abstract":"<div><div>Ferrite type magnetic nanoparticles composed of iron oxide and a metallic element have been attracting considerable interest in manifold applications due to their valuable physical, mechanical, optical, catalytic, and magnetic properties. However, the magnetic properties of ferrite nanoparticles produced via various conventional methods often fall short of the desired specifications for many applications. It is essential to develop an easy, cost-effective, and non-toxic method of preparation. A relatively facile, cost-effective and environment friendly method has been a key focus of research. This study aims to synthesize the MgFe₂O₄ (MFO) spinel ferrite using eco-friendly freshly extracted egg-white albumin method and study the detailed structural as well as the high temperature magnetic characteristics over a wide range of temperature from 2 K to 900 K. The phase purity, particle size, morphology, surface features, elemental confirmation, optical properties, elemental states as well as the magnetic characteristics of the prepared MFO nanoparticles were discussed. The prepared MFO nanoparticles were exhibited a cubic crystal structure in confirmation to a space group of Fd-3 m with an average particle size of 20 nm. UV–Visible absorption analysis of MFO nanoparticles showed an optical band gap of 3.32 eV. Mixed spinel type of MFO is confirmed from XPS spectra. The temperature variation of hysteresis loop suggested a super paramagnetic like behavior, however, a finite coercivity (H_c) was observed. The H_c, M_r, and M_s of the MFO nanoparticles were observed to be 50Oe, 2 emu/g and 26 emu/g, respectively. It was observed from the e M_r/M_s ratio of MFO nanoparticles that the particles are transforming into multi domain in nature above 100 K. The temperature variation of magnetization studies revealed a transition temperature is at around 588 K. Detailed magnetic behavior is investigated and explained by the models supported by theoretical studies.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"662 ","pages":"Article 128174"},"PeriodicalIF":1.7,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143792245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Growth of hexagonal BN crystals by traveling-solvent floating zone","authors":"Eli Zoghlin ,&nbsp;Juliette Plo ,&nbsp;Gaihua Ye ,&nbsp;Cynthia Nnokwe ,&nbsp;Reina Gomez ,&nbsp;Austin Ferrenti ,&nbsp;Satya Kushwaha ,&nbsp;Rui He ,&nbsp;Stephen D. Wilson ,&nbsp;Pierre Valvin ,&nbsp;Bernard Gil ,&nbsp;Guillaume Cassabois ,&nbsp;James H. Edgar ,&nbsp;Tyrel M. McQueen","doi":"10.1016/j.jcrysgro.2025.128164","DOIUrl":"10.1016/j.jcrysgro.2025.128164","url":null,"abstract":"<div><div>Large, high-purity single-crystals of hexagonal BN (h-BN) are essential for exploiting its many desirable and interesting properties. Here, we demonstrate via X-ray tomography, X-ray diffraction and scanning electron microscopy that h-BN crystals can be grown by traveling-solvent floating-zone (TSFZ). The diameters of grown boules range from 3 – 5 mm with lengths from 2 – 10 mm. Tomography indicates variable grain sizes within the boules, with the largest having areas of <span><math><mo>≈</mo></math></span> 1 mm <span><math><mo>×</mo></math></span> 2 mm and thickness <span><math><mo>≈</mo></math></span> 0.5 mm. Although the boules contain macroscale flux inclusions, the h-BN lattice itself is of high quality for samples grown under optimized conditions. The currently optimized growth procedure employs an Fe flux, moderate N<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> pressure (<span><math><mrow><msub><mrow><mi>P</mi></mrow><mrow><mi>N</mi><mn>2</mn></mrow></msub><mo>≈</mo></mrow></math></span> 6 bar), and a growth rate of 0.1 mm/h. Raman spectroscopy for an optimized sample gives an average linewidth of 7.7(2) cm⁻¹ for the E<span><math><msub><mrow></mrow><mrow><mi>2g</mi></mrow></msub></math></span> intralayer mode at 1365.46(4) cm⁻¹ and 1.0(1) cm⁻¹ for the E<span><math><msub><mrow></mrow><mrow><mi>2g</mi></mrow></msub></math></span> interlayer shear mode at 51.78(9) cm⁻¹. The corresponding photoluminescence spectrum shows sharp phonon-assisted free exciton peaks and minimal signal in the energy range corresponding to carbon-related defects (<span><math><mi>E</mi></math></span> = 3.9 – 4.1 eV). Our work demonstrates the viability of growing h-BN by the TSFZ technique, thereby opening a new route towards larger, high-quality crystals and advancing the state of h-BN related research.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"661 ","pages":"Article 128164"},"PeriodicalIF":1.7,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143783756","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of the crystal size and chemical composition on the optical properties of diamond films grown by hot filament chemical vapor deposition","authors":"Jorge Montes ,&nbsp;Jorge Vazquez ,&nbsp;Jorge Jurado ,&nbsp;Ángela Marín ,&nbsp;Jesús Alcántar ,&nbsp;Hugo Tiznado ,&nbsp;Frank Romo ,&nbsp;Orlando Auciello ,&nbsp;Oscar Contreras ,&nbsp;Rafael García-Gutiérrez","doi":"10.1016/j.jcrysgro.2025.128166","DOIUrl":"10.1016/j.jcrysgro.2025.128166","url":null,"abstract":"<div><div>This article is focused on describing the optical properties of different polycrystalline diamond thin films grown by hot filament chemical vapor deposition (HFCVD). The study correlates the influence of the crystal size and the composition to the optical properties of the diamond thin films. It was found that the diamond films grain sizes are depending on the precursor gases flow rates during film growth. All diamond films grown in this work exhibit the Raman peak corresponding to the G-band signal at 1560 cm⁻¹ associated to C–C sp² chemical bonds of C atoms in gran boundaries. Ellipsometry was used to determine the optical constants and refractive index of these polycrystalline diamond films using light beam 633 nm wavelength. The refractive index for micro-crystalline diamond (MCD) and nano-crystalline diamond (NCD) films was 2.33 and the ultra-nanocrystalline (UNCD) films presented a refractive index of 2.62. This research is an attempt to provide valuable information on the relation between the films structure, surface topography, chemical composition, and optical properties for a series of polycrystalline diamond films grown by HFCVD. The polycrystalline diamond films synthetized in this work should find applications in the fabrication of sensors, planar waveguide and in the development of opto-electronic devices.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"662 ","pages":"Article 128166"},"PeriodicalIF":1.7,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143792326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}