Abstract: A method of producing graphene or other two-dimensional material such as graphene including heating the substrate held within a reaction chamber to a temperature that is within a decomposition range of a precursor, and that allows two-dimensional crystalline material formation from a species released from the decomposed precursor; establishing a steep temperature gradient (preferably >1000° C. per meter) that extends away from the substrate surface towards an inlet for the precursor; and introducing precursor through the relatively cool inlet and across the temperature gradient towards the substrate surface. The steep temperature gradient ensures that the precursor remains substantially cool until it is proximate the substrate surface thus minimizing decomposition or other reaction of the precursor before it is proximate the substrate surface. The separation between the precursor inlet and the substrate is less than 100 mm.

Abstract: A method for manufacturing polycrystalline silicon fragments includes producing a polycrystalline silicon rod by the Siemens method; crushing the polycrystalline silicon rod to obtain polycrystalline silicon fragments; and cleaning by etching the polycrystalline silicon fragments in a cleaning tank. In the cleaning, small pieces of the polycrystalline silicon having controlled shapes and sizes are present in the cleaning tank and the weight change of the small pieces of the polycrystalline silicon before and after the etching is measured to thereby manage the cleaning.

Abstract: The present disclosure relates to a silicon-based fusion composition used for a solution growth method for forming a silicon carbide single crystal, and represented by the following Formula 1, including silicon, a first metal (M1), scandium (Sc) and aluminum (Al): SiaM1bSccAld??(Formula 1) wherein a is more than 0.4 and less than 0.8, b is more than 0.2 and less than 0.6, c is more than 0.01 and less than 0.1, and d is more than 0.01 and less than 0.1.

Abstract: A method of forming a plurality of diamonds provides a base, epitaxially forms a first sacrificial layer on the base, and then epitaxially forms a first diamond layer on the first sacrificial layer. The first sacrificial layer has a first material composition, and the first diamond layer is a material that is different from the first material composition. The method then epitaxially forms a second sacrificial layer on the first diamond layer, and epitaxially forms a second diamond layer on the second sacrificial layer. The second sacrificial layer has the first material composition. The base, first and second sacrificial layers, and first and second diamond layers form a heteroepitaxial super-lattice.

Abstract: The present disclosure provides an open Czochralski furnace for single crystal growth. The crystal growth apparatus may include a furnace chamber which includes a furnace body and a furnace cover. The furnace cover may be mounted on a top of the furnace body. The furnace cover may include a first through hole. The first through hole may be configured to place a temperature field. The crystal growth apparatus in the present disclosure can solve a problem that a traditional vacuum furnace needs to firstly pump a high vacuum and secondly recharge a protecting gas, thereby improving the apparatus safety; simplify the structure of the furnace body such that components that need maintenance and repair can be disassembled quickly, thereby reducing manufacturing and maintenance costs; improve the operation accuracy and stability of the apparatus; and reduce the influence of heat convection on the stability of weighing signals in the open furnace.

Abstract: A silicon-based molten composition according to an exemplary embodiment of the present invention is used in a solution growing method for forming silicon carbide single crystal, and is expressed in Formula 1 including silicon (Si), chromium (Cr), vanadium (V), and aluminum (Al). SiaCrbVcAld??[Formula 1] In Formula 1, a is equal to or greater than 0.4 and equal to or less than 0.9, b+c is equal to or greater than 0.1 and equal to or less than 0.6, c/(b+c) is equal to or greater than 0.05 and equal to or less than 0.95, and d is equal to or greater than 0.01 and equal to or less than 0.1.

Abstract: A method of controlling a convection pattern of a silicon melt includes: acquiring a temperature at a first measurement point not overlapping a rotation center of a quartz crucible on a surface of the silicon melt, the quartz crucible rotating in a magnetic-field-free state; determining that the temperature at the first measurement point periodically changes; and fixing a direction of a convection flow to a single direction in a plane orthogonal with an application direction of a horizontal magnetic field in the silicon melt by starting a drive of a magnetic-field applying portion to apply the horizontal magnetic field to the silicon melt when a temperature change at the first measurement point reaches a predetermined state, and subsequently raising the intensity to 0.2 tesla or more.

Abstract: A method for manufacturing an ultra small grain-size nanocrystalline diamond film having a SiV photoluminescence, comprises: (1) manufacturing, on a single crystal silicon substrate, a nanocrystalline diamond film having a SiV photoluminescence by using a microwave plasma chemical vapor deposition method; (2) performing oxygen plasma etching treatment on the nanocrystalline diamond film obtained in step (1) for 5-30 min by using an oxygen plasma bombardment method in a mixed gas plasma having an oxygen-nitrogen gas volume ratio of 1:4-6 and at an atmospheric pressure of 0.5-6 torr and a microwave power of 600-1000 W, thereby obtaining the ultra small grain-size nanocrystalline diamond film having the SiV photoluminescence.

Abstract: Fabrication of doped AlN crystals and/or AlGaN epitaxial layers with high conductivity and mobility is accomplished by, for example, forming mixed crystals including a plurality of impurity species and electrically activating at least a portion of the crystal.

Abstract: The present disclosure provides an open Czochralski furnace for single crystal growth. The crystal growth apparatus may include a furnace chamber which includes a furnace body and a furnace cover. The furnace cover may be mounted on a top of the furnace body. The furnace cover may include a first through hole. The first through hole may be configured to place a temperature field. The crystal growth apparatus in the present disclosure can solve a problem that a traditional vacuum furnace needs to firstly pump a high vacuum and secondly recharge a protecting gas, thereby improving the apparatus safety; simplify the structure of the furnace body such that components that need maintenance and repair can be disassembled quickly, thereby reducing manufacturing and maintenance costs; improve the operation accuracy and stability of the apparatus; and reduce the influence of heat convection on the stability of weighing signals in the open furnace.

Abstract: A film formation apparatus is configured to supply mist of a solution to a surface of a substrate so as to grow a film on the surface of the substrate, and the film formation apparatus may include: a furnace configured to house the substrate so as to heat the substrate; and a mist supply apparatus configured to supply the mist of the solution to the furnace, in which the film formation apparatus includes a portion configured to be exposed to the mist, and at least a part of the portion of the film formation apparatus is constituted of a material comprising boron nitride.

Abstract: Embodiments disclosed herein are related to polycrystalline textured materials exhibiting heterogeneous templated grain growth, methods of forming such materials, and related systems. An example of a method of forming a polycrystalline textured material exhibiting heterogeneous templated grain growth includes providing a plurality of seeds. The method also includes aligning at least some of the plurality of seeds (e.g., single-crystal seeds) so that a selected crystallographic orientation of at least some of the plurality of seeds are substantially aligned with each other. Additionally, the method includes positioning the plurality of seeds in a powder matrix. The method then includes pressing the plurality of seeds and the powdered matrix to form a green body. Further, the method includes sintering the green body at a temperature that is sufficient to grow a plurality of grains from corresponding ones of the plurality of seeds to form the polycrystalline textured material.

Abstract: A method for preparing a single crystal silicon ingot and a wafer sliced therefrom are provided. The ingots and wafers comprise nitrogen at a concentration of at least about 1×1014 atoms/cm3 and/or germanium at a concentration of at least about 1×1019 atoms/cm3, interstitial oxygen at a concentration of less than about 6 ppma, and a resistivity of at least about 1000 ohm cm.

Abstract: A method for producing a silicon ingot includes withdrawing a seed crystal from a melt that includes melted silicon in a crucible that is enclosed in a vacuum chamber containing a cusped magnetic field. At least one process parameter is regulated in at least two stages, including a first stage corresponding to formation of the silicon ingot up to an intermediate ingot length, and a second stage corresponding to formation of the silicon ingot from the intermediate ingot length to the total ingot length. During the second stage process parameter regulation may include reducing a crystal rotation rate, reducing a crucible rotation rate, and/or increasing a magnetic field strength relative to the first stage.

Abstract: A method is disclosed for reducing the size and density of defects in a single crystal silicon wafer. The method involves subjected a single crystal silicon ingot to an anneal prior to wafer slicing.

Abstract: A monocrystalline germanium wafer that increases the open-circuit voltage of multijunction solar cells, a method for preparing the monocrystalline germanium wafer and a method for preparing an ingot from which the monocrystalline germanium wafer is prepared. The monocrystalline germanium wafer that increases the open-circuit voltage of the bottom cell of multijunction solar cells is prepared by adjusting the amounts of the co-dopants silicon and gallium in the monocrystalline germanium wafer, the ratio of silicon to gallium in the preparation of the monocrystalline germanium.

Abstract: Bulk single crystal of aluminum nitride (AlN) having an areal planar defect density ?100 cm?2. Methods for growing single crystal aluminum nitride include melting an aluminum foil to uniformly wet a foundation with a layer of aluminum, the foundation forming a portion of an AlN seed holder, for an AlN seed to be used for the AlN growth. The holder may consist essentially of a substantially impervious backing plate.

Abstract: Provided is a method of accurately predicting the thermal donor formation behavior in a silicon wafer, a method of evaluating a silicon wafer using the prediction method, and a method of producing a silicon wafer using the evaluation method. The method of predicting the formation behavior of thermal donors, includes: a first step of setting an initial oxygen concentration condition before performing heat treatment on the silicon wafer for reaction rate equations based on both a bond-dissociation model of oxygen clusters associated with the diffusion of interstitial oxygen and a bonding model of oxygen clusters associated with the diffusion of oxygen dimers; a second step of calculating the formation rate of oxygen clusters formed through the heat treatment using the reaction rate equations; and a third step of calculating the formation rate of thermal donors formed through the heat treatment based on the formation rate of the oxygen clusters.

Abstract: A method for growing a single crystal silicon ingot by the continuous Czochralski method is disclosed. The melt depth and thermal conditions are constant during growth because the silicon melt is continuously replenished as it is consumed, and the crucible location is fixed. The critical v/G is determined by the hot zone configuration, and the continuous replenishment of silicon to the melt during growth enables growth of the ingot at a constant pull rate consistent with the critical v/G during growth of a substantial portion of the main body of the ingot. The continuous replenishment of silicon is accompanied by periodic or continuous nitrogen addition to the melt to result in a nitrogen doped ingot.

Abstract: A method for growing a single crystal silicon ingot by the continuous Czochralski method is disclosed. The melt depth and thermal conditions are constant during growth because the silicon melt is continuously replenished as it is consumed, and the crucible location is fixed. The critical v/G is determined by the hot zone configuration, and the continuous replenishment of silicon to the melt during growth enables growth of the ingot at a constant pull rate consistent with the critical v/G during growth of a substantial portion of the main body of the ingot. The continuous replenishment of silicon is accompanied by periodic or continuous nitrogen addition to the melt to result in a nitrogen doped ingot.