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The continuous-feeding Czochralski method is a cost-effective method to grow single silicon crystals. An inner crucible is used to prevent the un-melted silicon feedstock from transferring to the melt-crystal interface in this method. A series of global simulations were carried out to investigate the impact of the inner crucible on the oxygen impurity distributions at the melt-crystal interface. The results indicate that, the inner crucible plays a more important role in affecting the O concentration at the melt-crystal interface than the outer crucible. It can prevent the oxygen impurities from being transported from the outer crucible wall effectively. Meanwhile, it also introduces as a new source of oxygen impurity in the melt, likely resulting in a high oxygen concentration zone under the melt-crystal interface. We proposed to enlarge the inner crucible diameter so that the oxygen concentration at the melt-crystal interface can be controlled at low levels.

Silicon wafers are essential components in the production of various devices, including integrated circuits, microchips, and solar cells. The quality and characteristics of silicon wafers greatly influence the performance and reliability of these devices. Silicon wafers have been produced through processes like the Czochralski method, which involves growing a single crystal ingot of silicon and then slicing it into thin wafers. While effective, these methods have limitations in terms of scalability, cost, and uniformity. Recent advancements in silicon wafer production focus on improving efficiency, reducing costs, and enhancing quality. The innovations in silicon wafer production and finishing have significant implications for various industries, including electronics, telecommunications, automotive, and renewable energy. This article provides an overview of the production of high-purity silicon, a vital component in semiconductor device manufacturing. A comprehensive description related to the extraction of silicon from silica, the refinement of metallurgical grade silicon (MGS) to achieve high purity. Additionally, the article covers various processes involved in silicon wafer manufacturing, including cutting, shaping, polishing, and cleaning, and explores advancements in technology that could enhance wafer manufacturing capabilities.

β-Ga2O3 is a well-known semiconductor material for power devices and other applications. Recently, β-Ga2O3 has also been reported as a scintillator material with a light yield of approximately 8400 ph./MeV, scintillation decay time of <1 μs, and density of 6.44 g/cm3. In this study, 45 cm diameter β-Ga2O3 single crystals were prepared via oxide crystal growth using the cold crucible (OCCC) method under various oxygen partial pressures. In the OCCC method, as in the cold crucible method, a high frequency is applied directly to the oxide materials, which are heated and melted, and the melt is held by the outermost solid material itself that is cooled by water using a copper hearth. In the OCCC method, crystal growth is performed while rotating the seed crystal, as in the Czochralski method, to increase the crystal diameter. The optical properties and radiation responses of the crystals grown under various oxygen partial pressures were evaluated.

The continuous Czochralski (CCz) method is a low-cost and high-efficiency method for the production of monocrystalline silicon. The inner crucible is an extremely important component in the CCz method. In this work, the crystal silicon rod production process with a diameter of 215.00 mm is simulated to study how the inner crucible radius influences the thermal field of the melt and the melt-crystal (m-c) interface shape with the outer crucible size remaining constant. Additionally, the effects of varying the inner crucible radius on the Von Mises stress within the crystal and the distribution of oxygen impurities in the melt are also examined. The results show that when the radius of the outer crucible is fixed, the required heater power increases slightly with the increase of the inner crucible radius. However, the convexity and deflection of the m-c interface, the Von Mises stress inside the crystal, and the oxygen impurities content at the crystal growth interface decrease with the increase of the inner crucible radius. Therefore, the larger inner crucible size is favorable for silicon crystal production using CCz. The results of this work can improve the production efficiency and quality of the silicon crystal.

Abstract—Selective etching is used to assess the structural perfection (dislocation density) of single crystals in production conditions owing to its high informativity and relatively low laboriousness. However, the interpretation of data being obtained may vary depending on the choice of the type of regulatory documentation. The results of determining the criterion for the morphological classification of etching pits using digital image processing are presented. InSb (111) single crystals grown by the Czochralski method and doped with tellurium are analyzed. Using the sequential selective etching, it is established that the pointed-peaked pits on the InSb (111) surface, regardless of their size, are most likely of dislocation origin. In turn, clusters of pits of “regular” shape, which disappear during repeat etching, probably arise in sites where point defects emerge on the surface and are unrelated to the formation of Lomer–Cottrell barriers or other dislocation clusters. Based on an analysis of the brightness field, a criterion for differentiating etching pits is proposed by determining the value of the average pixel intensity. The results can be used in the production of structures for matrix and linear photodetectors, as well as in the optimization of technological parameters for the growth of single crystals using the Czochralski method.

Separation of refined silicon from Al–Si melt is still a puzzle for the solvent refining process, resulting in considerable waste of acid and silicon powder. A novel modified Czochralski method within the Al–Si alloy is proposed. After the modified Czochralski process, a large amount of refined Si particles was enriched around the seed crystalline Si and separated from the Al–Si melt. As for the Al–28%Si with the pulling rate of 0.001 mm/min, the recovery of refined Si in the pulled-up alloy (PUA) sample is 21.5%, an improvement of 22% compared with the theoretical value, which is much larger 1.99 times than that in the remained alloy (RA) sample. The content of impurities in the PUA is much less than that in the RA sample, which indicates that the modified Czochralski method is effective to improve the removal fraction of impurities. The apparent segregation coefficients of boron (B) and phosphorus (P) in the PUA and RA samples were evaluated. These results demonstrate that the modified Czochralski method for the alloy system is an effective way to enrich and separate refined silicon from the Al–Si melt, which provide a potential and clean production of solar grade silicon (SoG-Si) for the future industrial application.

The silicon single crystals for semiconductor application are usually grown by the Czochralski (CZ) method. In this paper, we studied a 300 mm Czochralski silicon crystal grown with a cusp magnetic field to be used for an insulated gate bipolar transistor (IGBT). Different positions of the zero-Gauss plane (ZGP) under a cusp magnetic field were simulated and compared to numerical analysis. We investigated three factors that affected the oxygen concentration in the crystal, including (1) melt convection, (2) melt flow velocity near the quartz crucible wall, and (3) the diffusion boundary layer. We also studied the shape of the solid/liquid interface at the same time. The simulation results show that a change in the ZGP of the cusp magnetic field (CMF) strongly affects the convection in the melt, which leads to a difference in the thickness of the boundary layer near the wall of the quartz crucible. We investigated the relationship of the ZGP, convection in the melt, and the thickness of the boundary layer. In this way, we determined how to reduce oxygen diffusing into the melt and finally into the crystal. After simulation results were obtained, we pulled single crystals under the three configurations. The results show that the experimental data of the oxygen content and shape of the solid/liquid interfaces are consistent with the simulation results.

This paper presents the preparation of Z-cut near-stoichiometric lithium niobate (NSLN) wafers using a combined process of the lithium-rich Czochralski growth and diffusion methods. The fabricated Z-cut NSLN wafers exhibited outstanding comprehensive performance, including a high Curie temperature of up to 1200 °C, a refractive index gradient in the diameter direction below 1.5 × 10−4 cm−1, and a UV absorption edge shifted 14 nm toward the ultraviolet region compared to congruent lithium niobate crystals, with a coercive field of 1268 V/mm. Additionally, the wafers demonstrated excellent processing characteristics, with the bow of 4-inch wafers controlled within 55 μm, surpassing the machining standards of traditional lithium niobate wafers of the same size. These results indicated the highly uniform chemical stoichiometry and crystallization quality of the wafers. Leveraging the high uniformity and low coercive field of the wafers, periodic triangular domain structure arrays were successfully fabricated, laying the foundation for domain engineering design in electro-optic deflectors and switching devices. This study not only achieves the scalable preparation of NSLN wafers but also provides a reliable technical solution for their practical applications in high-performance electro-optic devices.

There is a demand for the manufacture of two-dimensional (2D) materials with high-quality single crystals of large size. Usually, epitaxial growth is considered the method of choice1 in preparing single-crystalline thin films, but it requires single-crystal substrates for deposition. Here we present a different approach and report the synthesis of single-crystal-like monolayer graphene films on polycrystalline substrates. The technological realization of the proposed method resembles the Czochralski process and is based on the evolutionary selection2 approach, which is now realized in 2D geometry. The method relies on ‘self-selection’ of the fastest-growing domain orientation, which eventually overwhelms the slower-growing domains and yields a single-crystal continuous 2D film. Here we have used it to synthesize foot-long graphene films at rates up to 2.5 cm h−1 that possess the quality of a single crystal. We anticipate that the proposed approach could be readily adopted for the synthesis of other 2D materials and heterostructures.

Batch production of single-crystal two-dimensional (2D) transition metal dichalcogenides is one prerequisite for the fabrication of next-generation integrated circuits. Contemporary strategies for the wafer-scale high-quality crystallinity of 2D materials centre on merging unidirectionally aligned, differently sized domains. However, an imperfectly merged area with a translational lattice brings about a high defect density and low device uniformity, which restricts the application of the 2D materials. Here we establish a liquid-to-solid crystallization in 2D space that can rapidly grow a centimetre-scale single-crystal MoS 2 domain with no grain boundaries. The large MoS 2 single crystal obtained shows superb uniformity and high quality with an ultra-low defect density. A statistical analysis of field effect transistors fabricated from the MoS 2 reveals a high device yield and minimal variation in mobility, positioning this FET as an advanced standard monolayer MoS 2 device. This 2D Czochralski method has implications for fabricating high-quality and scalable 2D semiconductor materials and devices. A 2D Czochralski method is introduced for rapidly growing centimetre-scale single-crystal MoS 2 domains with low defect density and impressive electrical performance. This method shows potential for fabricating high-quality and scalable 2D semiconductor materials and devices.