A biomedical implant (16, 18) is formed from magnesium (Mg) single crystal (10). The biomedical implant (16, 18) may be biodegradable. The biomedical implant (16, 18) may be post treated to control the mechanical properties and/or corrosion rate thereof said Mg single crystal (10) without changing the chemical composition thereof. A method of making a Mg single crystal (10) for biomedical applications includes filling a single crucible (12) with more than one chamber with polycrystalline Mg, melting at least a portion of said polycrystalline Mg, and forming more than one Mg single crystal (10) using directional solidification.

The invention provides a growth method for preparing high-yield crystals, belongs to the technical field of single crystal growth. Auxiliary crucibles are arranged on a crucible according to different crystal types and according to the crystal orientation of crystal growth in the main crucible, the relationship between the crystal growth direction and twin crystal orientation. By controlling the angle between the auxiliary crucibles and the main crucible, the relative position between the auxiliary crucibles each other, the auxiliary crucibles realize correction on the crystal orientation of twins generated in the main crucible crystal growth process. The growth method for preparing the high-yield crystals provided by the invention has the following advantages: the crystal orientation change caused by twins is corrected through auxiliary crucibles additionally arranged on the main crucible, and the overall yield is improved for the growth process of the dislocation crystal with large probability; the crucible position can be customized according to the influence of twins on the crystal growth direction, suitable for various crystal preparation processes, improving the yield obviously, reducing the crystal processing difficulty, and improving the material utilization rate.

The present disclosure discloses a method for growing a crystal with a short decay time. According to the method, a new single crystal furnace and a temperature field device are adapted and a process, a ration of reactants, and growth parameters are adjusted and/or optimized, accordingly, a crystal with a short decay time, a high luminous intensity, and a high luminous efficiency can be grown without a co-doping operation.

Dust that is accumulated in an exhaust passage provided in a chamber, the exhaust passage for discharging gas in the chamber of a semiconductor crystal manufacturing device, is removed by being sucked from the outside of the chamber. Moreover, an opening and closing valve for cleaning that is detachably attached to an opening of the exhaust passage, the opening facing the chamber, is opened and closed intermittently in a suction state. Furthermore, the opening and closing valve for cleaning is driven by a valve driving unit. The dust accumulated in the exhaust passage is removed efficiently, whereby the time required to clean the exhaust passage is shortened and fluctuations of the pressure inside the chamber when a semiconductor crystal is manufactured are suppressed.

Dust that is accumulated in an exhaust passage provided in a chamber, the exhaust passage for discharging gas in the chamber of a semiconductor crystal manufacturing device, is removed by being sucked from the outside of the chamber. Moreover, an opening and closing valve for cleaning that is detachably attached to an opening of the exhaust passage, the opening facing the chamber, is opened and closed intermittently in a suction state. Furthermore, the opening and closing valve for cleaning is driven by a valve driving unit. The dust accumulated in the exhaust passage is removed efficiently, whereby the time required to clean the exhaust passage is shortened and fluctuations of the pressure inside the chamber when a semiconductor crystal is manufactured are suppressed.

According to the present invention, there is provided a method for manufacturing single crystal based on a Czochralski method, including: analyzing Ni concentration in at least one of graphite components used in a furnace in which the single crystal is manufactured; and manufacturing the single crystal using the at least one of the graphite components when the analyzed Ni concentration is 30 ppb or less. As a result, in manufacture of the single crystal based on the Czochralski method, the method that enables manufacturing high-quality single crystal in which a reduction in LT (Life Time) or an LPD (Light Point Defect) abnormality does not occur can be provided.

According to the present invention, there is provided a method for manufacturing single crystal based on a Czochralski method, including: analyzing Ni concentration in at least one of graphite components used in a furnace in which the single crystal is manufactured; and manufacturing the single crystal using the at least one of the graphite components when the analyzed Ni concentration is 30 ppb or less. As a result, in manufacture of the single crystal based on the Czochralski method, the method that enables manufacturing high-quality single crystal in which a reduction in LT (Life Time) or an LPD (Light Point Defect) abnormality does not occur can be provided.

A single-crystal manufacturing apparatus including: main chamber accommodating crucible and heater; pull chamber wherein a grown single-crystal is received; gas-flow guiding cylinder that has opening through which the single-crystal passes and extends downward from ceiling of main chamber; seed chuck configured to hold a seed crystal; and heat insulation plate that is level with lower end of the opening of gas-flow guiding cylinder when raw material is heated and melted, and pulled together with the seed crystal when single-crystal is pulled. The seed chuck includes a mounting fixture to mount heat insulation plate. Mounting fixture has a mechanism allowing heat insulation plate to be mounted so the heat insulation plate can be rotated independently of the rotation of the seed chuck. This apparatus can be readily introduced, melt raw material with low heater power; inhibit occurrence of dislocation during seeding and generation of dislocation in single-crystal when single-crystal is pulled.

A single-crystal manufacturing apparatus including: main chamber accommodating crucible and heater; pull chamber wherein a grown single-crystal is received; gas-flow guiding cylinder that has opening through which the single-crystal passes and extends downward from ceiling of main chamber; seed chuck configured to hold a seed crystal; and heat insulation plate that is level with lower end of the opening of gas-flow guiding cylinder when raw material is heated and melted, and pulled together with the seed crystal when single-crystal is pulled. The seed chuck includes a mounting fixture to mount heat insulation plate. Mounting fixture has a mechanism allowing heat insulation plate to be mounted so the heat insulation plate can be rotated independently of the rotation of the seed chuck. This apparatus can be readily introduced, melt raw material with low heater power; inhibit occurrence of dislocation during seeding and generation of dislocation in single-crystal when single-crystal is pulled.

An object of the present invention is to provide a method for comparatively simply selecting polycrystalline silicon suitably used for stably producing single crystal silicon in high yield. According to the present invention, polycrystalline silicon having a maximum surface roughness (Peak-to-Valley) value Rpv of 5000 nm or less, an arithmetic average roughness value Ra of 600 nm or less and a root mean square roughness value Rq of 600 nm or less, the surface roughness values being measured by observing with an atomic force microscope (AFM) the surface of a collected plate-shaped sample, is selected as a raw material for producing single crystal silicon.