Pub Date : 2025-10-20DOI: 10.1016/j.jcrysgro.2025.128375
Seongho Kang , Yukyeong Cha , Kyu-Yeon Shim , Eojin-Gyere Ham, Dohoon Kim, Dongjin Byun
Gallium nitride (GaN)-based micro-light-emitting diodes (LEDs) have attracted attention as next-generation display devices owing to their low-power and long-life characteristics. In particular, through selective-area growth (SAG) of core–shell structures, m-plane light emission and quantum-confined Stark effect mitigation can be achieved simultaneously. The realization of such structures requires a precise SAG process and an efficient liftoff technique. In this study, a maskless chromium nitride (CrN) dot-patterned substrate was fabricated to implement a selective GaN growth process, and the effect of the initial low-temperature GaN (LT-GaN) layer on SAG was systematically analyzed. By evaluating the surface properties at each growth stage, it was confirmed that the CrN dot region maintained a high-polarity component and surface energy and provided favorable conditions for the selective nucleation of GaN precursors. This is attributed to selective GaN growth exclusively on the CrN dots, resulting from the combined effect of LT-GaN particle reorganization and the surface thermodynamic properties of CrN. This study is experimentally demonstrated for the feasibility of mask-free III-nitride selection growth technology, which can be used as a core technology for future micro-LED processes.
{"title":"Mask-free selective GaN growth driven by LT-GaN redistribution on patterned CrN buffers","authors":"Seongho Kang , Yukyeong Cha , Kyu-Yeon Shim , Eojin-Gyere Ham, Dohoon Kim, Dongjin Byun","doi":"10.1016/j.jcrysgro.2025.128375","DOIUrl":"10.1016/j.jcrysgro.2025.128375","url":null,"abstract":"<div><div>Gallium nitride (GaN)-based micro-light-emitting diodes (LEDs) have attracted attention as next-generation display devices owing to their low-power and long-life characteristics. In particular, through selective-area growth (SAG) of core–shell structures, m-plane light emission and quantum-confined Stark effect mitigation can be achieved simultaneously. The realization of such structures requires a precise SAG process and an efficient liftoff technique. In this study, a maskless chromium nitride (CrN) dot-patterned substrate was fabricated to implement a selective GaN growth process, and the effect of the initial low-temperature GaN (LT-GaN) layer on SAG was systematically analyzed. By evaluating the surface properties at each growth stage, it was confirmed that the CrN dot region maintained a high-polarity component and surface energy and provided favorable conditions for the selective nucleation of GaN precursors. This is attributed to selective GaN growth exclusively on the CrN dots, resulting from the combined effect of LT-GaN particle reorganization and the surface thermodynamic properties of CrN. This study is experimentally demonstrated for the feasibility of mask-free III-nitride selection growth technology, which can be used as a core technology for future micro-LED processes.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"672 ","pages":"Article 128375"},"PeriodicalIF":2.0,"publicationDate":"2025-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145414776","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}
Pub Date : 2025-10-19DOI: 10.1016/j.jcrysgro.2025.128370
Kohei Shima, Haruto Tsujitani, Shigefusa F. Chichibu
sp2-bonded BN films exhibiting deep-ultraviolet luminescence peaks were grown by metalorganic chemical vapor deposition using tris(dimethylamino)borane [TDMAB, B[N(CH3)2]3] and NH3 as B and N sources, respectively. BN films with thicknesses ranging from 0.7 to 6.1 µm were grown at temperatures () between 1200 and 1500 °C, under mass-transport-limited growth conditions. The results of x-ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, Raman-scattering spectroscopy, and x-ray photoelectron spectroscopy confirmed the dominance of turbostratic BN and the presence of partially ordered structures such as ABC-stacked rhombohedral phases, along with minor contributions from B-O and C-N bonds. The films exhibited broad cathodoluminescence bands centered at 5.5 eV, 4.1 eV, and 3.2 eV, which are attributable to stacking defects, most probably C impurities, and possibly O impurities, respectively. One of the samples exhibited distinct zero-phonon lines at 4.14 and 4.16 eV attributable to C dimer defects in ABC-stacked (rhombohedral) and AB-stacked (Bernal) BN phases, respectively. Compared with a reference BN epilayer grown using the BCl3-NH3-N2 gas system, B[N(CH3)2]3-grown films exhibited approximately twofold higher cathodoluminescence intensities in the 5.2–6.1 eV range at 300 K, likely due to the reduced incorporation of nonradiative recombination centers. The cathodoluminescence intensity was maximized at = 1400 °C, while both higher and lower resulted in higher concentrations of nonradiative recombination centers, likely associated with C-N bonds and divacancies comprising a B-vacancy and a N-vacancy, VBVN, respectively. These results demonstrate that B[N(CH3)2]3 is a suitable B source for the deposition of luminescent BN films, offering the potential for improved deep-ultraviolet emitter performance through reduced impurity incorporation.
{"title":"Deep-ultraviolet luminescence from sp2-bonded BN films grown by metalorganic chemical vapor deposition using tris(dimethylamino)borane","authors":"Kohei Shima, Haruto Tsujitani, Shigefusa F. Chichibu","doi":"10.1016/j.jcrysgro.2025.128370","DOIUrl":"10.1016/j.jcrysgro.2025.128370","url":null,"abstract":"<div><div><em>sp</em><sup>2</sup>-bonded BN films exhibiting deep-ultraviolet luminescence peaks were grown by metalorganic chemical vapor deposition using tris(dimethylamino)borane [TDMAB, B[N(CH<sub>3</sub>)<sub>2</sub>]<sub>3</sub>] and NH<sub>3</sub> as B and N sources, respectively. BN films with thicknesses ranging from 0.7 to 6.1 µm were grown at temperatures (<span><math><mrow><msub><mi>T</mi><mi>g</mi></msub></mrow></math></span>) between 1200 and 1500 °C, under mass-transport-limited growth conditions. The results of x-ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, Raman-scattering spectroscopy, and x-ray photoelectron spectroscopy confirmed the dominance of turbostratic BN and the presence of partially ordered structures such as ABC-stacked rhombohedral phases, along with minor contributions from B-O and C-N bonds. The films exhibited broad cathodoluminescence bands centered at 5.5 eV, 4.1 eV, and 3.2 eV, which are attributable to stacking defects, most probably C impurities, and possibly O impurities, respectively. One of the samples exhibited distinct zero-phonon lines at 4.14 and 4.16 eV attributable to C dimer defects in ABC-stacked (rhombohedral) and AB-stacked (Bernal) BN phases, respectively. Compared with a reference BN epilayer grown using the BCl<sub>3</sub>-NH<sub>3</sub>-N<sub>2</sub> gas system, B[N(CH<sub>3</sub>)<sub>2</sub>]<sub>3</sub>-grown films exhibited approximately twofold higher cathodoluminescence intensities in the 5.2–6.1 eV range at 300 K, likely due to the reduced incorporation of nonradiative recombination centers. The cathodoluminescence intensity was maximized at <span><math><mrow><msub><mi>T</mi><mi>g</mi></msub></mrow></math></span> = 1400 °C, while both higher and lower <span><math><mrow><msub><mi>T</mi><mi>g</mi></msub></mrow></math></span> resulted in higher concentrations of nonradiative recombination centers, likely associated with C-N bonds and divacancies comprising a B-vacancy and a N-vacancy, V<sub>B</sub>V<sub>N</sub>, respectively. These results demonstrate that B[N(CH<sub>3</sub>)<sub>2</sub>]<sub>3</sub> is a suitable B source for the deposition of luminescent BN films, offering the potential for improved deep-ultraviolet emitter performance through reduced impurity incorporation.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"672 ","pages":"Article 128370"},"PeriodicalIF":2.0,"publicationDate":"2025-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145340021","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}
Control over nano- and microstructure of metal oxide materials is increasingly important, as it allows for fine-tuning their functionality. Material science provided a plethora of template and template-free methods to synthesize substrates with developed morphology, high crystallinity, and large specific concentration of reactive centers. Titanium phosphates (TiP), a wide group of materials composed of earth-abundant elements, are a versatile platform for the development of materials with customizable morphology and elemental composition. Ease of their synthesis and modification provided multiple sorbents, catalysts, energy capacitor electrodes and polymer additives. Elaboration of hierarchical structures in titanium phosphates beyond the regular and uniform nanocrystalline units produced substrates with a significant surplus in functionality. Although further studies in this direction seem perspective, little work was devoted to controlling features of the TiP hierarchical structure. Here, we report on a screening of general thermodynamic parameters of the hydrothermal synthesis of microspherical titanium phosphate. TiP microspheres change in size according to the Ostwald ripening mechanism with full retention of hierarchical structure. Deviations from this mechanism observed at high concentrations of phosphoric acid are explained in relation to the features of the constituting elements of the microspheres.
{"title":"Ostwald ripening behind the hierarchical structure evolution of titanium phosphate","authors":"Anton Abramian , Danil Man’ko , Valeria Zakharchenkova , Viacheslav Avdin , Oleg Bol’shakov","doi":"10.1016/j.jcrysgro.2025.128373","DOIUrl":"10.1016/j.jcrysgro.2025.128373","url":null,"abstract":"<div><div>Control over nano- and microstructure of metal oxide materials is increasingly important, as it allows for fine-tuning their functionality. Material science provided a plethora of template and template-free methods to synthesize substrates with developed morphology, high crystallinity, and large specific concentration of reactive centers. Titanium phosphates (TiP), a wide group of materials composed of earth-abundant elements, are a versatile platform for the development of materials with customizable morphology and elemental composition. Ease of their synthesis and modification provided multiple sorbents, catalysts, energy capacitor electrodes and polymer additives. Elaboration of hierarchical structures in titanium phosphates beyond the regular and uniform nanocrystalline units produced substrates with a significant surplus in functionality. Although further studies in this direction seem perspective, little work was devoted to controlling features of the TiP hierarchical structure. Here, we report on a screening of general thermodynamic parameters of the hydrothermal synthesis of microspherical titanium phosphate. TiP microspheres change in size according to the Ostwald ripening mechanism with full retention of hierarchical structure. Deviations from this mechanism observed at high concentrations of phosphoric acid are explained in relation to the features of the constituting elements of the microspheres.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"671 ","pages":"Article 128373"},"PeriodicalIF":2.0,"publicationDate":"2025-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145360107","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}
Pub Date : 2025-10-17DOI: 10.1016/j.jcrysgro.2025.128372
Arianna Jaroszynska, Petro Sadovyi, Karol Pozyczka, Michal Fijalkowski, Pawel Kempisty, Robert Kucharski, Michal Bockowski, Tomasz Sochacki
This study explores the impact of hydrogen admixture in the nitrogen carrier gas on the growth of aluminum-gallium nitride layers using halide vapor phase epitaxy. Thermodynamic modeling was used to estimate supersaturation for gallium nitride and aluminium nitride formation for different hydrogen admixtures. Simulations showed that hydrogen suppresses gallium nitride crystallization while having minimal influence on aluminum nitride. Growth experiments with 0 % and 10 % hydrogen in the carrier gas confirmed this model: aluminum content increased from 3.6 at.% to 11.4 at.% with a corresponding drop in growth rate from 13.5 μm/h to 4.5 μm/h. Additional experiments were conducted with optimized precursor flows and extended durations, ultimately resulting in the growth of a 60 μm-thick aluminum-gallium nitride layer containing 8.4 at.% aluminum content. These findings validate the simulation model and demonstrate that hydrogen can serve as an important parameter during bulk growth of aluminum gallium nitride. The process developed in this work represents a step toward the production of thick, compositionally controlled aluminum gallium nitride layers, supporting future efforts to fabricate free-standing substrates through iterative seed removal and regrowth.
{"title":"The influence of hydrogen admixture in the carrier gas on aluminum gallium nitride growth in halide vapor phase epitaxy","authors":"Arianna Jaroszynska, Petro Sadovyi, Karol Pozyczka, Michal Fijalkowski, Pawel Kempisty, Robert Kucharski, Michal Bockowski, Tomasz Sochacki","doi":"10.1016/j.jcrysgro.2025.128372","DOIUrl":"10.1016/j.jcrysgro.2025.128372","url":null,"abstract":"<div><div>This study explores the impact of hydrogen admixture in the nitrogen carrier gas on the growth of aluminum-gallium nitride layers using halide vapor phase epitaxy. Thermodynamic modeling was used to estimate supersaturation for gallium nitride and aluminium nitride formation for different hydrogen admixtures. Simulations showed that hydrogen suppresses gallium nitride crystallization while having minimal influence on aluminum nitride. Growth experiments with 0 % and 10 % hydrogen in the carrier gas confirmed this model: aluminum content increased from 3.6 at.% to 11.4 at.% with a corresponding drop in growth rate from 13.5 μm/h to 4.5 μm/h. Additional experiments were conducted with optimized precursor flows and extended durations, ultimately resulting in the growth of a 60 μm-thick aluminum-gallium nitride layer containing 8.4 at.% aluminum content. These findings validate the simulation model and demonstrate that hydrogen can serve as an important parameter during bulk growth of aluminum gallium nitride. The process developed in this work represents a step toward the production of thick, compositionally controlled aluminum gallium nitride layers, supporting future efforts to fabricate free-standing substrates through iterative seed removal and regrowth.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"671 ","pages":"Article 128372"},"PeriodicalIF":2.0,"publicationDate":"2025-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145359658","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}
Pub Date : 2025-10-14DOI: 10.1016/j.jcrysgro.2025.128371
Ha Young Kang, Jaeheon Jung, Young Soo Hwang, Roy B. Chung
This study systematically explores the structural factors influencing κ-phase gallium oxide (κ-Ga2O3) thin film growth and domain formation on non-basal plane substrates. Accordingly, we grew κ-Ga2O3 thin films using mist chemical vapor deposition on both basal and non-basal plane sapphire (c-, a-, m-, and r-plane) and GaN (c- and m-plane) substrates for analysis. Crystallinity, orientation, and domain structures were assessed by X-ray diffraction including 2θ–ω scans, rocking curves, and φ-scans. On c- and a-plane sapphire and GaN substrates, κ-Ga2O3 with c-axis orientation was selectively stabilized, whereas α-Ga2O3 predominantly formed on r- and m-plane sapphire. Regardless of substrate symmetry, all κ-Ga2O3 films exhibited persistent three-fold rotational domains, highlighting the limitations of current substrate configurations. These results demonstrate the significant influence of substrate atomic arrangement on phase stability and domain control, emphasizing the need for advanced substrate engineering to realize single-domain κ-Ga2O3 thin films with improved crystalline quality.
{"title":"Influence of substrate atomic symmetry on the epitaxy and rotational domain formation of κ-Ga2O3","authors":"Ha Young Kang, Jaeheon Jung, Young Soo Hwang, Roy B. Chung","doi":"10.1016/j.jcrysgro.2025.128371","DOIUrl":"10.1016/j.jcrysgro.2025.128371","url":null,"abstract":"<div><div>This study systematically explores the structural factors influencing κ-phase gallium oxide (κ-Ga<sub>2</sub>O<sub>3</sub>) thin film growth and domain formation on non-basal plane substrates. Accordingly, we grew κ-Ga<sub>2</sub>O<sub>3</sub> thin films using mist chemical vapor deposition on both basal and non-basal plane sapphire (c-, a-, m-, and r-plane) and GaN (c- and m-plane) substrates for analysis. Crystallinity, orientation, and domain structures were assessed by X-ray diffraction including 2θ–ω scans, rocking curves, and φ-scans. On c- and a-plane sapphire and GaN substrates, κ-Ga<sub>2</sub>O<sub>3</sub> with c-axis orientation was selectively stabilized, whereas α-Ga<sub>2</sub>O<sub>3</sub> predominantly formed on r- and m-plane sapphire. Regardless of substrate symmetry, all κ-Ga<sub>2</sub>O<sub>3</sub> films exhibited persistent three-fold rotational domains, highlighting the limitations of current substrate configurations. These results demonstrate the significant influence of substrate atomic arrangement on phase stability and domain control, emphasizing the need for advanced substrate engineering to realize single-domain κ-Ga<sub>2</sub>O<sub>3</sub> thin films with improved crystalline quality.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"671 ","pages":"Article 128371"},"PeriodicalIF":2.0,"publicationDate":"2025-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145326237","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}
Pub Date : 2025-10-14DOI: 10.1016/j.jcrysgro.2025.128355
Yingzhao Geng , Yang Xu , Xu Li , Xiao Wang , Hao Wu , Chang Liu
InN thin films have been deposited on fluorophlogopite mica (F-mica) substrates by molecular beam epitaxy (MBE) under various growth conditions. The N2 flow rate and radio-frequency (RF) power were adjusted to realize N-rich and In-rich growth conditions. During the transition from N-rich to In-rich conditions, the plateaus formed by partially coalesced larger grains or islands were observed, which was attributed to the short diffusion length of indium (In) atoms. Meanwhile, the In-rich InN thin films exhibit lower dislocation densities than those of N-rich thin films. Under In-rich conditions, similar plateaus were also observed at lower growth temperatures. Additionally, the surface roughness and total dislocation density were reduced by increasing the growth and In source temperatures to 490 and 775 °C. Throughout all growth condition, the in-plane epitaxial relationship remains as InN [110]//F-mica [010].
{"title":"Molecular beam epitaxy of flexible InN thin films on fluorophlogopite mica","authors":"Yingzhao Geng , Yang Xu , Xu Li , Xiao Wang , Hao Wu , Chang Liu","doi":"10.1016/j.jcrysgro.2025.128355","DOIUrl":"10.1016/j.jcrysgro.2025.128355","url":null,"abstract":"<div><div>InN thin films have been deposited on fluorophlogopite mica (F-mica) substrates by molecular beam epitaxy (MBE) under various growth conditions. The N<sub>2</sub> flow rate and radio-frequency (RF) power were adjusted to realize N-rich and In-rich growth conditions. During the transition from N-rich to In-rich conditions, the plateaus formed by partially coalesced larger grains or islands were observed, which was attributed to the short diffusion length of indium (In) atoms. Meanwhile, the In-rich InN thin films exhibit lower dislocation densities than those of N-rich thin films. Under In-rich conditions, similar plateaus were also observed at lower growth temperatures. Additionally, the surface roughness and total dislocation density were reduced by increasing the growth and In source temperatures to 490 and 775 °C. Throughout all growth condition, the in-plane epitaxial relationship remains as InN [110]//F-mica [010].</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"671 ","pages":"Article 128355"},"PeriodicalIF":2.0,"publicationDate":"2025-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145326234","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}
Pub Date : 2025-10-14DOI: 10.1016/j.jcrysgro.2025.128369
Minh-Anh Nguyen Tran , Van Quang Nguyen , Cao Khang Nguyen , Sunglae Cho
In this work, we systematically investigate the epitaxial growth of GaSe thin films on different substrates, including GaAs(100), GaAs(111), GaN/Al2O3(0001), and SrTiO3(001), using molecular beam epitaxy (MBE). All films exhibit a universal strain configuration with biaxial tensile strain in the basal plane coupled with out-of-plane compressive strain, whose magnitude varies with substrate type. On cubic GaAs substrates, GaSe grows with well-aligned single domains, while hexagonal GaN and perovskite STO promote multiple domain orientations, reflecting the role of interfacial symmetry mismatch. X-ray diffraction confirms out-of-plane lattice contraction, with compressive strain ranging from ∼1.3 % on GaAs(1 0 0) to ∼2.5 % on GaN(0001). Raman spectroscopy shows red-shifts of the in-plane phonon mode, directly evidencing biaxial tensile strain. These findings demonstrate that substrate-induced strain, governed primarily by symmetry mismatch, provides a powerful and intrinsic route to tailor the optical and electronic properties of GaSe, enabling new strategies for strain-engineered 2D optoelectronic devices.
{"title":"Strain modulation in 2D GaSe epitaxial films by substrate engineering via molecular beam epitaxy (MBE)","authors":"Minh-Anh Nguyen Tran , Van Quang Nguyen , Cao Khang Nguyen , Sunglae Cho","doi":"10.1016/j.jcrysgro.2025.128369","DOIUrl":"10.1016/j.jcrysgro.2025.128369","url":null,"abstract":"<div><div>In this work, we systematically investigate the epitaxial growth of GaSe thin films on different substrates, including GaAs(100), GaAs(111), GaN/Al<sub>2</sub>O<sub>3</sub>(0001), and SrTiO<sub>3</sub>(001), using molecular beam epitaxy (MBE). All films exhibit a universal strain configuration with biaxial tensile strain in the basal plane coupled with out-of-plane compressive strain, whose magnitude varies with substrate type. On cubic GaAs substrates, GaSe grows with well-aligned single domains, while hexagonal GaN and perovskite STO promote multiple domain orientations, reflecting the role of interfacial symmetry mismatch. X-ray diffraction confirms out-of-plane lattice contraction, with compressive strain ranging from ∼1.3 % on GaAs(1<!--> <!-->0<!--> <!-->0) to ∼2.5 % on GaN(0001). Raman spectroscopy shows red-shifts of the in-plane <span><math><msubsup><mi>E</mi><mrow><mn>2</mn><mi>g</mi></mrow><mn>2</mn></msubsup></math></span> phonon mode, directly evidencing biaxial tensile strain. These findings demonstrate that substrate-induced strain, governed primarily by symmetry mismatch, provides a powerful and intrinsic route to tailor the optical and electronic properties of GaSe, enabling new strategies for strain-engineered 2D optoelectronic devices.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"671 ","pages":"Article 128369"},"PeriodicalIF":2.0,"publicationDate":"2025-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145326236","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}
Pub Date : 2025-10-13DOI: 10.1016/j.jcrysgro.2025.128343
Debajani Rout , R. Kulkarni , A. Thamizhavel , Santosh Kumar
We report the growth of single crystals of the non-centrosymmetric material YCoC2 by the Czochralski technique using a tetra arc furnace. This compound belongs to the family of rare-earth transition-metal carbides, the members of which exhibit a wide range of interesting phenomena including topological semimetallic behaviour. We have investigated the magnetic and transport properties of YCoC2. The results of resistivity measurements revealed a typical metallic behaviour across the temperature range, 4 < T < 300 K. At T = 3.9(1) K, a transition in both magnetization and resistivity measurements has been observed. This feature has been explored in detail with the temperature-dependent magnetization M(T) and resistivity ρ(T) measurements carried out at different magnetic fields.
本文报道了在四弧炉中，用Czochralski法生长非中心对称材料YCoC2的单晶。该化合物属于稀土过渡金属碳化物家族，其成员表现出广泛的有趣现象，包括拓扑半金属行为。我们研究了YCoC2的磁性和输运性质。电阻率测量结果显示在4 <； T <； 300 K的温度范围内具有典型的金属行为。在T = 3.9(1) K时，磁化率和电阻率测量值都发生了转变。在不同磁场下进行的温度相关磁化强度M(T)和电阻率ρ(T)测量详细探讨了这一特征。
{"title":"Single crystal growth, study of magnetic and transport properties in the noncentrosymmetric material YCoC2","authors":"Debajani Rout , R. Kulkarni , A. Thamizhavel , Santosh Kumar","doi":"10.1016/j.jcrysgro.2025.128343","DOIUrl":"10.1016/j.jcrysgro.2025.128343","url":null,"abstract":"<div><div>We report the growth of single crystals of the non-centrosymmetric material YCoC<sub>2</sub> by the Czochralski technique using a tetra arc furnace. This compound belongs to the family of rare-earth transition-metal carbides, the members of which exhibit a wide range of interesting phenomena including topological semimetallic behaviour. We have investigated the magnetic and transport properties of YCoC<sub>2</sub>. The results of resistivity measurements revealed a typical metallic behaviour across the temperature range, 4 < <em>T</em> < 300 K. At <em>T</em> = 3<em>.</em>9(1) K, a transition in both magnetization and resistivity measurements has been observed. This feature has been explored in detail with the temperature-dependent magnetization <em>M</em>(<em>T</em>) and resistivity <em>ρ</em>(<em>T</em>) measurements carried out at different magnetic fields.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"671 ","pages":"Article 128343"},"PeriodicalIF":2.0,"publicationDate":"2025-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145326238","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}
Pub Date : 2025-10-12DOI: 10.1016/j.jcrysgro.2025.128366
Ya Li , Jing Liang , Yucong Lin , Yu Lu , Zhifeng Wang , Houfu Dai , Jian Li
Zinc oxide (ZnO) films hold significant value in the field of optoelectronic devices due to their exceptional properties as wide bandgap semiconductors. Although Metal-Organic Chemical Vapor Deposition (MOCVD) technology enables the production of high-quality thin film epitaxy, its industrial application continues to encounter persistent challenges related to inadequate deposition uniformity and efficiency. In this research, we employed a novel vertical reaction chamber ZnO-MOCVD device to systematically investigate the synergistic mechanisms governing multiple parameters—including MO source, O source, Ar carrier gas flow rate, and observation window flow rate—through multi-physics coupled numerical simulations and orthogonal experimental design. The results demonstrate that precisely adjusting the O source flow velocity effectively mitigates vortex phenomena within the turntable, thereby stabilizing the laminar flow state. Increasing the inlet flow rate suppresses the thermal buoyancy effect and reduces the risk of gas-phase pre-reaction. The synergistic regulation of MO and O flow velocities significantly enhances the uniformity of diethyl zinc (DEZn) and oxygen (O2) distribution. Orthogonal analysis successfully identified the optimal combination of process parameters, resulting in an exceptional deposition rate (0.2049 μm/h) and a coefficient of variation (4 %), thereby fully validating the effectiveness of the multi-parameter collaborative optimization strategy. This research provides an important theoretical foundation for MOCVD equipment process design and offers crucial guidance for advancing the industrial preparation of high-performance ZnO films.
{"title":"Research on MOCVD structure design and process parameters based on CFD numerical simulation","authors":"Ya Li , Jing Liang , Yucong Lin , Yu Lu , Zhifeng Wang , Houfu Dai , Jian Li","doi":"10.1016/j.jcrysgro.2025.128366","DOIUrl":"10.1016/j.jcrysgro.2025.128366","url":null,"abstract":"<div><div>Zinc oxide (ZnO) films hold significant value in the field of optoelectronic devices due to their exceptional properties as wide bandgap semiconductors. Although Metal-Organic Chemical Vapor Deposition (MOCVD) technology enables the production of high-quality thin film epitaxy, its industrial application continues to encounter persistent challenges related to inadequate deposition uniformity and efficiency. In this research, we employed a novel vertical reaction chamber ZnO-MOCVD device to systematically investigate the synergistic mechanisms governing multiple parameters—including MO source, O source, Ar carrier gas flow rate, and observation window flow rate—through multi-physics coupled numerical simulations and orthogonal experimental design. The results demonstrate that precisely adjusting the O source flow velocity effectively mitigates vortex phenomena within the turntable, thereby stabilizing the laminar flow state. Increasing the inlet flow rate suppresses the thermal buoyancy effect and reduces the risk of gas-phase pre-reaction. The synergistic regulation of MO and O flow velocities significantly enhances the uniformity of diethyl zinc (DEZn) and oxygen (O<sub>2</sub>) distribution. Orthogonal analysis successfully identified the optimal combination of process parameters, resulting in an exceptional deposition rate (0.2049 μm/h) and a coefficient of variation (4 %), thereby fully validating the effectiveness of the multi-parameter collaborative optimization strategy. This research provides an important theoretical foundation for MOCVD equipment process design and offers crucial guidance for advancing the industrial preparation of high-performance ZnO films.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"671 ","pages":"Article 128366"},"PeriodicalIF":2.0,"publicationDate":"2025-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145326235","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}
Pub Date : 2025-10-11DOI: 10.1016/j.jcrysgro.2025.128356
Yisong Yang , Sha Chen , Zhishun Wei , Ying Chang , Yan Xiong , Junxiang Zhao , Hu Zhu , Min Li , Qirui Yang , Guoqiang Yi
This study proposes a method involving stirring after a constant-temperature water bath in a salt solution to enhance the crystal size, overall homogeneity, and hydration strength of α-hemihydrate gypsum (α-HH). Utilizing by-product gypsum from the chlor-alkali industry as raw material, the influence of Mg2+ ions on phase evolution and final morphology was systematically investigated. During the constant-temperature water bath process in salt solution, the neutral MgSO40 ion pairs formed by Mg2+ and SO42- facilitated the dissolution of dihydrate gypsum (DH) while amplifying the solubility difference between α-HH and DH, thereby promoting preferential crystallization and precipitation of α-HH. Furthermore, Mg2+ inhibited crystal growth along the c-axis direction during α-HH development, effectively reducing the aspect ratio. The subsequent stirring process significantly increased secondary nucleation probability, enabling mutual adhesion among α-HH crystals of varying dimensions. This synergistic process ultimately yielded enlarged α-HH crystals with an average particle size of 143.21 μm and aspect ratio of 5.57. The flexural strength and absolute dry compressive strength of bulk samples prepared from these α-HH crystals are discussed in detail, demonstrating substantial improvements in mechanical properties compared to conventional preparation methods.
{"title":"Growth of large-sized α-HH via Mg2+-involved atmospheric salt bath-stirring strategy: crystallization mechanism and enhanced mechanical properties","authors":"Yisong Yang , Sha Chen , Zhishun Wei , Ying Chang , Yan Xiong , Junxiang Zhao , Hu Zhu , Min Li , Qirui Yang , Guoqiang Yi","doi":"10.1016/j.jcrysgro.2025.128356","DOIUrl":"10.1016/j.jcrysgro.2025.128356","url":null,"abstract":"<div><div>This study proposes a method involving stirring after a constant-temperature water bath in a salt solution to enhance the crystal size, overall homogeneity, and hydration strength of α-hemihydrate gypsum (α-HH). Utilizing by-product gypsum from the chlor-alkali industry as raw material, the influence of Mg<sup>2+</sup> ions on phase evolution and final morphology was systematically investigated. During the constant-temperature water bath process in salt solution, the neutral MgSO<sub>4</sub><sup>0</sup> ion pairs formed by Mg<sup>2+</sup> and SO<sub>4</sub><sup>2-</sup> facilitated the dissolution of dihydrate gypsum (DH) while amplifying the solubility difference between α-HH and DH, thereby promoting preferential crystallization and precipitation of α-HH. Furthermore, Mg<sup>2+</sup> inhibited crystal growth along the c-axis direction during α-HH development, effectively reducing the aspect ratio. The subsequent stirring process significantly increased secondary nucleation probability, enabling mutual adhesion among α-HH crystals of varying dimensions. This synergistic process ultimately yielded enlarged α-HH crystals with an average particle size of 143.21 μm and aspect ratio of 5.57. The flexural strength and absolute dry compressive strength of bulk samples prepared from these α-HH crystals are discussed in detail, demonstrating substantial improvements in mechanical properties compared to conventional preparation methods.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"671 ","pages":"Article 128356"},"PeriodicalIF":2.0,"publicationDate":"2025-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145326233","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}
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