Journal of Crystal Growth最新文献

{"title":"230 nm electron-beam excited light source with AlGaN/AlN multiple quantum wells on face-to-face annealed sputter-deposited AlN template","authors":"Ryoya Iwase ,&nbsp;Ryota Akaike ,&nbsp;Hiroki Yasunaga ,&nbsp;Takao Nakamura ,&nbsp;Masayoshi Nagao ,&nbsp;Katsuhisa Murakami ,&nbsp;Hideto Miyake","doi":"10.1016/j.jcrysgro.2025.128142","DOIUrl":"10.1016/j.jcrysgro.2025.128142","url":null,"abstract":"<div><div>We conducted a comprehensive investigation into the optimal architecture of light-emitting devices operating in the 230 nm wavelength band, which were fabricated face-to-face by annealing sputter-deposited AlN templates for electron-beam excitation. The structures and multiple quantum wells were systematically optimized. The present findings revealed that employing AlN as the underlayer and the barrier layers produced significant improvements in surface smoothness and enhanced cathodoluminescence intensity. Moreover, the optimized device was successfully integrated with a graphene-based electron source, facilitating light emission through electron-beam excitation and achieving a power efficiency of 0.16 %. Remarkably, this power efficiency remained stable with increasing injected current from the graphene-based electron source, demonstrating a linear increase in light output without the efficiency droop associated with conventional light-emitting diodes. These results validate the potential of a simplified device structure that eliminates the need for a p-type layer, aiding the development of large-area, high-output light sources within the 230 nm band.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"660 ","pages":"Article 128142"},"PeriodicalIF":1.7,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143679748","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":"Crystals grown from precipitant-free ultralow concentrate ATP (adenosine triphosphate) solutions with extremely low DC potential","authors":"Abani K. Bhuyan","doi":"10.1016/j.jcrysgro.2025.128140","DOIUrl":"10.1016/j.jcrysgro.2025.128140","url":null,"abstract":"<div><div>ATP crystals are grown under bare conditions of DC potential, ionic strength, and solute concentration without a precipitant. A 1.6 V cm⁻¹ DC field supplied internally to aqueous solutions containing as low as 0.003 mg mL⁻¹ ATP in 1 mM phosphate buffer appears sufficient for the growth of orthorhombic crystals. The effect of the electric field (EF) on molecular ionization and monomer → aggregate transition are analyzed by UV–visible and fluorescence spectroscopy. The aggregation process starts in less than an hour after turning the DC field on, and the aggregates appear to nucleate and enter the crystal phase in hours or days. Processes innate to electrochemistry are minimized or do not interfere with the interaction of the EF with the molecular dipole, forcing predominant aggregation in the solution itself. The crystals are imaged and indexed using electron microscopy and powder X-ray diffractogram. A series of experiments in which the amount crystallized as a function of initial concentration of ATP in the 0.003–13 mg mL⁻¹ range was determined yields an indicator isotherm of crystallization at 298 K that shows that the amount of ATP used up to produce the crystalline phase decreases rapidly with the initial concentration used.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"659 ","pages":"Article 128140"},"PeriodicalIF":1.7,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143684073","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":"Study on the influence of 36-inch hot field heater structure on the oxygen content of Czochralski monocrystalline silicon","authors":"Duan Xiaochen ,&nbsp;Huang Xuguang ,&nbsp;Wang Yulong ,&nbsp;Chai Chen ,&nbsp;Han Qinghui ,&nbsp;Ma Haotian ,&nbsp;Bai Guijie","doi":"10.1016/j.jcrysgro.2025.128144","DOIUrl":"10.1016/j.jcrysgro.2025.128144","url":null,"abstract":"<div><div>CZ method utilizes a quartz crucible to grow solar-grade monocrystalline silicon. The primary component of the quartz crucible is SiO2, which contributes most of the oxygen and negatively impacts the efficiency of solar cells. CGSim numerical simulation software is employed to analyze the effects of heating power, interfacial stress, melt flow, and silicon-oxygen content at varying heights of the main heater. The results indicate that shortening the main heater can increase power, expand the low-temperature region of the melt, and weaken the melt convection along the sides of the crucible, thereby reducing the precipitated oxygen content (from 7.11 × 10^17 atoms/cm³ to 5.85 × 10^17 atoms/cm³, a reduction of 17.7 %). After the addition of a second heater, the crystal oxygen content is further decreased by 8.7 %, with the minimum oxygen content reaching 5.34 × 10^17 atoms/cm³. According to production data, shortening the main heater and incorporating a second heater can lead to a 24.6 % reduction in oxygen content, demonstrating a significant decrease in oxygen levels.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"659 ","pages":"Article 128144"},"PeriodicalIF":1.7,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143644328","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":"Iron-induced low background impurity and high resistivity GaN films grown by MOCVD on patterned sapphire substrates","authors":"Song Fu,&nbsp;Qun Ma,&nbsp;Yang Li,&nbsp;Junjie Kang,&nbsp;Meng Liang,&nbsp;Xiaoyan Yi,&nbsp;Junxi Wang,&nbsp;Jinmin Li,&nbsp;Zhiqiang Liu","doi":"10.1016/j.jcrysgro.2025.128141","DOIUrl":"10.1016/j.jcrysgro.2025.128141","url":null,"abstract":"<div><div>Electrically insulating GaN epilayers with good crystal quality are essential but challenging for power electronics. Iron (Fe) doping is a valuable method to achieve high resistivity GaN grown by metal–organic chemical vapor deposition (MOCVD). Here, we investigated the impacts of Fe dopants on growth kinetics and electron transition processes in GaN. It is found that the Fe dopants act as surfactants during growth, facilitating the coalescence of GaN and thus effectively limiting the incorporation of oxygen (O) impurities from the substrates into epilayers by 30 times. Meanwhile, the Fe dopants induce a (0/-) transition level, 0.59 eV below the conduction band minimum, which serves as electron traps capturing free electrons and resulting in high resistivity. The relevant mechanism was discussed in detail, and a quantitative model was established, with the consideration of free electron density, donor and Fe concentration, and temperature. Benefit from those, GaN films on patterned sapphire substrates (PSS) with a dislocation density of 1.3 × 10⁸ cm⁻², a resistivity up to 7.4 × 10⁹ Ω∙cm, and free of intentional Fe doping at the surface of the epilayer can be achieved. The clarification of Fe dopants in GaN paves the way for future advanced electronic devices and applications.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"659 ","pages":"Article 128141"},"PeriodicalIF":1.7,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143645029","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 and thermal expansion properties of KYbxY1-x(WO4)2 single crystals for laser applications","authors":"S.A. Guretskii ,&nbsp;D.V. Karpinsky ,&nbsp;E.L. Trukhanova ,&nbsp;K.V. Yumashev ,&nbsp;E.E. Trusova ,&nbsp;N.V. Kuleshov","doi":"10.1016/j.jcrysgro.2025.128139","DOIUrl":"10.1016/j.jcrysgro.2025.128139","url":null,"abstract":"<div><div>Single crystals of KYb_xY_1-x(WO₄)₂ of high optical quality were grown at a rate of about</div><div>4.0 mm/day by the modified Czochralski method. The crystals have been grown using the so-called dynamic growth regime. The optimal temperature gradients have been determined at the crystallization front. Thermal expansion coefficients of KYb<em>_x</em>Y_1-<em>_x</em>(WO₄)₂ are determined in the directions of the optical indicatrix axes N_p, N_m and N_g in the temperature range of 60 – 300 °C using dilatometric technique.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"659 ","pages":"Article 128139"},"PeriodicalIF":1.7,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143637319","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":"Single crystal growth of 1T-VSe2 by molten salt flux method","authors":"Muhammed Anees K.T.,&nbsp;Souvik Kumar Rana,&nbsp;Abinash Das,&nbsp;Moumita Nandi","doi":"10.1016/j.jcrysgro.2025.128135","DOIUrl":"10.1016/j.jcrysgro.2025.128135","url":null,"abstract":"<div><div>VSe<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> is a highly promising van der Waals (vdW) material for applications in electronics, spintronics, and optoelectronics. Here, we report single crystal growth of 1T-VSe<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> (octahedral structure) by flux method using eutectic of NaCl/KCl molten salt. The typical size of as-grown VSe<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> single crystals is 5 × 4 × 0.1 mm<span><math><msup><mrow></mrow><mrow><mn>3</mn></mrow></msup></math></span>. The elemental composition and homogeneity of the crystals were examined by energy dispersive x-ray spectroscopy, which is consistent with the stoichiometric ratio of VSe<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>. The crystallographic [001] direction has been determined by x-ray diffraction. Raman measurement confirms that the octahedral 1T structure of VSe<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> has been formed. Temperature-dependent resistivity measurement exhibits a transition around 104 K due to the formation of the charge density wave phase.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"659 ","pages":"Article 128135"},"PeriodicalIF":1.7,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143590358","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":"Modification mechanisms of the primary Al13Fe4 phase in hypereutectic Al–Fe alloys by La element: Experiments and first–principles study","authors":"Na Pang,&nbsp;Zhiming Shi,&nbsp;Cunquan Wang,&nbsp;Hao Lian,&nbsp;Jiacheng Liu","doi":"10.1016/j.jcrysgro.2025.128136","DOIUrl":"10.1016/j.jcrysgro.2025.128136","url":null,"abstract":"<div><div>The primary Al₁₃Fe₄ phase prefers to grow along the [010] orientation and form flakes, coarse needles, and lath shapes, which significantly impairs the mechanical properties of hypereutectic Al–Fe alloys. In this work, 1 wt% La addition is shown to greatly improve the morphology of the primary Al₁₃Fe₄ phase and have the most efficient refinement effect on Al–5Fe alloy. According to the data, La atoms mainly formed Al₁₁La₃ phase and were not found in the primary Al₁₃Fe₄ phase. The DSC thermal analysis revealed that La addition increased the crystallization temperature range and decreased the crystallization enthalpy of the primary Al₁₃Fe₄ phase. The results of the first-principles calculation indicated that La preferentially occupied Al sites when entering the primary Al₁₃Fe₄ phase, thus leading to an increase in the formation enthalpy of Al₁₃Fe₄. Meanwhile, the surface energy decreased and the stability of the (010) surface was enhanced when La atoms replaced the specific Al atoms sites in the Al₁₃Fe₄ (010) surface. Moreover, La atoms were rather adsorbed on the Al₁₃Fe₄ (010) surface because of the exothermic nature of adsorption and its negative energy. Therefore, La atoms change the formation enthalpy and surface energy of the Al₁₃Fe₄ phase by doping and adsorption, and finally affect the crystal structure, crystallization process and morphology of the primary Al₁₃Fe₄ phase. The experimental results and theoretical calculations confirm that adsorption and constitutional undercooling are more likely to be the main modification mechanisms of the primary Al₁₃Fe₄ phase via La doping.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"659 ","pages":"Article 128136"},"PeriodicalIF":1.7,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143577079","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":"Temperature-dependent crystallization of TiO2: A pathway to optimize efficiency in perovskite solar cells","authors":"Gani Purwiandono ,&nbsp;Puji Lestari ,&nbsp;Fina Binazir Maziya ,&nbsp;Dara Rossa Alcintaka ,&nbsp;Rizky Fajrie Novriansyah","doi":"10.1016/j.jcrysgro.2025.128133","DOIUrl":"10.1016/j.jcrysgro.2025.128133","url":null,"abstract":"<div><div>This study investigates the fabrication of titanium dioxide (TiO₂) crystals and their use as electron transport layers (ETLs) in perovskite solar cells (PSC). We investigated the structural, morphological, and electrical properties of TiO₂ films by altering synthesis temperatures (60 °C, 70 °C, and 80 °C) and reaction periods. TiO₂ produced at 70 °C has the largest crystallite size and surface area, resulting in better film quality, according to the characterization of XRD, SEM, and TEM. The maximum conversion efficiency of 16.1 % is achieved by 70 °C TiO₂ films due to the improved charge extraction and lower recombination. These results show that optimizing the TiO₂ ETL and precisely controlling synthesis conditions improves PSC performance.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"659 ","pages":"Article 128133"},"PeriodicalIF":1.7,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143548982","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":"Sodium lauryl sulphate-mediated manganese doping to enhance photocatalytic performance of cadmium sulphide-manganese composite","authors":"Santhoshbalaji Muthuvijayan ,&nbsp;T. Theivasanthi ,&nbsp;Rajesh Kumar Manavalan ,&nbsp;Selvakumar Balasubramanian ,&nbsp;Subash C.B. Gopinath","doi":"10.1016/j.jcrysgro.2025.128125","DOIUrl":"10.1016/j.jcrysgro.2025.128125","url":null,"abstract":"<div><div>This research investigates the effect of manganese doping concentration in cadmium sulphide (CdS) nanoparticles synthesized using sodium lauryl sulfate (SLS) surfactant to improve photocatalytic activity. We systematically controlled the manganese precursor concentration at 0.004 g, 0.0099 g, 0.0148 g, 0.0198 g, and 0.0247 g to achieve optimal doping efficiency and modulate the structural transformation of CdS-Mn nanocomposites. It was observed that the bandgap energy varied between 2.16 eV and 2.27 eV. Forward scattering of the X-rays was measured for the crystal at an incident photon energy of 2.27 eV, depending on Mn concentration, using UV–Vis absorption spectra. XRD analysis of CdS confirmed its wurtzite form with a peak shift at 2θ ≈ 32°, attributed to lattice contraction upon Mn doping. Transmission electron microscopy analysis provided a particle size estimate of about 7–8 nm. The reduction of methylene blue through photocatalytic activity under UV light showed that the highest degradation efficiency was achieved with Mn doping at 0.0148 g. The presence of SLS improved nanoparticle dispersion, preventing particle agglomeration and requiring stabilization, which is essential for high photocatalytic activity. The findings of this study are valuable for understanding the interaction process between Mn-doped CdS nanoparticles and SLS, as well as the synergistic effects that effectively enhance photocatalytic performance.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"658 ","pages":"Article 128125"},"PeriodicalIF":1.7,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143518975","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":"3D numerical investigation of the factors affecting the thermal stresses and the wavy external shape of Li2MoO4 crystals grown by the Czochralski method","authors":"C. Stelian,&nbsp;M. Velazquez","doi":"10.1016/j.jcrysgro.2025.128134","DOIUrl":"10.1016/j.jcrysgro.2025.128134","url":null,"abstract":"<div><div>Three-dimensional (3D) modeling was applied to investigate heat transfer, convection and thermal stresses in Czochralski growth of Li₂MoO₄ (LMO) crystals used to build the core of heat-scintillation cryogenic bolometers (HSCBs). Several crystals of <span><math><mrow><mn>4</mn><mspace></mspace><mi>c</mi><mi>m</mi></mrow></math></span> and <span><math><mrow><mn>5</mn><mspace></mspace><mi>c</mi><mi>m</mi></mrow></math></span> in diameter were grown in two different Czochralski configurations. The largest ingot (<span><math><mrow><mn>4</mn><mspace></mspace><mi>c</mi><mi>m</mi></mrow></math></span>-diameter and <span><math><mrow><mn>6</mn><mspace></mspace><mi>c</mi><mi>m</mi></mrow></math></span>-length) grown in a furnace based on coupling the inductive coil and a platinum crucible, has cracked as the bottom part of the crystal was cut. Another crystal (<span><math><mrow><mn>5</mn><mspace></mspace><mi>c</mi><mi>m</mi></mrow></math></span>-diameter and <span><math><mrow><mn>15</mn><mspace></mspace><mi>c</mi><mi>m</mi></mrow></math></span>-length) was grown in a furnace based on inductive heating of a susceptor, which was previously optimized by numerical modeling in order to reduce the thermal stresses in LMO crystals. The external surface of this ingot shows a slightly wavy shape. This irregular shape was investigated by considering 3D convective effects at the free surface of the melt, which can affect the liquid meniscus shape, and generate slight instabilities of the growth process. It is concluded that this wavy shape can be avoided by changing the sensitivity of the automatic crystal shape control. The thermal stress computations, conducted for the ingot of <span><math><mrow><mn>4</mn><mspace></mspace><mi>c</mi><mi>m</mi></mrow></math></span> in diameter, show that the normal stress in the longitudinal section has a maximum which highly exceeds the critical value of the tensile stress in a region located at the bottom part of the ingot. That explains the fracture observed during the cutting of the ingot’s tail. The computations performed in the case of <span><math><mrow><mn>5</mn><mspace></mspace><mi>c</mi><mi>m</mi></mrow></math></span>-diameter ingot, grown in an optimized configuration, show that the crystal exhibits low thermal stress, except for a thin region of <span><math><mrow><mn>2</mn><mspace></mspace><mi>m</mi><mi>m</mi></mrow></math></span> located at the ingot periphery, where the stress slightly exceeds the critical value. Thermal stresses can be reduced by a factor of 2 by growing the ingots parallel to the c-axis.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"658 ","pages":"Article 128134"},"PeriodicalIF":1.7,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143520225","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}