C30B15/04

Method and apparatus for manufacturing monocrystalline silicon

A method for manufacturing a monocrystalline silicon with Czochralski process, including: providing polycrystalline silicon and dopant to quartz crucible in single crystal furnace and vacuumizing, melting the polycrystalline silicon under protective gas to obtain silicon melt; after temperature of the silicon melt is stable, immersing seed crystal into the silicon melt to start seeding, lifting a shield away from surface of the silicon melt to adjust distance between the shield and the silicon melt to first preset distance; after seeding, performing shouldering to pull the crystal to increase diameter of the crystal to preset width; starting constant-diameter body growth, lowering the shield towards the surface of the silicon melt to adjust the distance to second preset distance; after growth, entering a tailing stage during which the diameter of the crystal is reduced until the crystal is separated from the silicon melt; and cooling the crystal to obtain monocrystalline silicon.

N-type silicon single crystal production method, n-type silicon single crystal ingot, silicon wafer, and epitaxial silicon wafer

In a producing method of an n-type monocrystalline silicon by pulling up a monocrystalline silicon from a silicon melt containing a main dopant in a form of red phosphorus to grow the monocrystalline silicon, the monocrystalline silicon exhibiting an electrical resistivity ranging from 0.5 mΩcm to 1.0 mΩcm is pulled up using a quartz crucible whose inner diameter ranges from 1.7-fold to 2.3-fold relative to a straight-body diameter of the monocrystalline silicon.

N-type silicon single crystal production method, n-type silicon single crystal ingot, silicon wafer, and epitaxial silicon wafer

In a producing method of an n-type monocrystalline silicon by pulling up a monocrystalline silicon from a silicon melt containing a main dopant in a form of red phosphorus to grow the monocrystalline silicon, the monocrystalline silicon exhibiting an electrical resistivity ranging from 0.5 mΩcm to 1.0 mΩcm is pulled up using a quartz crucible whose inner diameter ranges from 1.7-fold to 2.3-fold relative to a straight-body diameter of the monocrystalline silicon.

SCINTILLATION CRYSTAL INCLUDING A CO-DOPED RARE EARTH SILICATE, A RADIATION DETECTION APPARATUS INCLUDING THE SCINTILLATION CRYSTAL, AND A PROCESS OF FORMING THE SAME
20220380667 · 2022-12-01 ·

A scintillation crystal can include a rare earth silicate, an activator, and a Group 2 co-dopant. In an embodiment, the Group 2 co-dopant concentration may not exceed 200 ppm atomic in the crystal or 0.25 at % in the melt before the crystal is formed. The ratio of the Group 2 concentration/activator atomic concentration can be in a range of 0.4 to 2.5. In another embodiment, the scintillation crystal may have a decay time no greater than 40 ns, and in another embodiment, have the same or higher light output than another crystal having the same composition except without the Group 2 co-dopant. In a further embodiment, a boule can be grown to a diameter of at least 75 mm and have no spiral or very low spiral and no cracks. The scintillation crystal can be used in a radiation detection apparatus and be coupled to a photosensor.

MANUFACTURING METHOD FOR SEMICONDUCTOR SILICON WAFER

A semiconductor silicon wafer manufacturing method is provided, where P aggregate defects and SF in an epitaxial layer can be suppressed. A silicon wafer substrate cut from a monocrystal ingot is doped with phosphorus and has a resistivity of 1.05 mΩ.Math.cm or less and a concentration of solid-solution oxygen of 0.9×10.sup.18 atoms/cm.sup.3. The method includes steps of mirror-polishing substrates and heat treatment, where after the mirror-polishing step, the substrate is kept at a temperature from 700° C. to 850° for 30 to 120 minutes, then after the temperature rise, kept at a temperature from 100° C. to 1250° for 30 to 120 minutes, and after cooling, kept at a temperature from 700° C. to 450° C. for less than 10 minutes as an experience time. The heat treatment step is performed in a mixture gas of hydrogen and argon. The method includes an epitaxial layer deposition step to a thickness of 1.3 μm to 10.0 μm.

METHOD AND APPARATUS FOR PULLING SINGLE CRYSTAL
20220364258 · 2022-11-17 · ·

A method and an apparatus of pulling single crystals are provided that allows adding dopants efficiently into the silicon melt without causing to generate dislocations and obtainment of single crystals with low resistivity, during forming the former half of a product portion after the formation of the shoulder, when pulled up from the silicon melt by the Czochralski method. The method includes steps of forming an inert gas flow G that flows from above toward the silicon melt M1 along the inside of a heat shield 7 disposed to surround the silicon crystal C to be grown in the furnace and expands in radial directions along the surface of the silicon melt and is exhausted to the outside of the furnace, gasifying a dopant in the furnace, discharging the gasified dopant into the inside of the heat shield, and flowing the gasified dopant carried by the inert gas flow.

METHOD AND APPARATUS FOR PULLING SINGLE CRYSTAL
20220364258 · 2022-11-17 · ·

A method and an apparatus of pulling single crystals are provided that allows adding dopants efficiently into the silicon melt without causing to generate dislocations and obtainment of single crystals with low resistivity, during forming the former half of a product portion after the formation of the shoulder, when pulled up from the silicon melt by the Czochralski method. The method includes steps of forming an inert gas flow G that flows from above toward the silicon melt M1 along the inside of a heat shield 7 disposed to surround the silicon crystal C to be grown in the furnace and expands in radial directions along the surface of the silicon melt and is exhausted to the outside of the furnace, gasifying a dopant in the furnace, discharging the gasified dopant into the inside of the heat shield, and flowing the gasified dopant carried by the inert gas flow.

Codoping method for modifying the scintillation and optical properties of garnet-type scintillators

A method of tailoring the properties of garnet-type scintillators to meet the particular needs of different applications is described. More particularly, codoping scintillators, such as Gd.sub.3Ga.sub.3Al.sub.2O.sub.12, Gd.sub.3Ga.sub.2Al.sub.3O.sub.12, or other rare earth gallium aluminum garnets, with different ions can modify the scintillation light yield, decay time, rise time, energy resolution, proportionality, and/or sensitivity to light exposure. Also provided are the codoped garnet-type scintillators themselves, radiation detectors and related devices comprising the codoped garnet-type scintillators, and methods of using the radiation detectors to detect gamma rays, X-rays, cosmic rays, and particles having an energy of 1 keV or greater.

Codoping method for modifying the scintillation and optical properties of garnet-type scintillators

A method of tailoring the properties of garnet-type scintillators to meet the particular needs of different applications is described. More particularly, codoping scintillators, such as Gd.sub.3Ga.sub.3Al.sub.2O.sub.12, Gd.sub.3Ga.sub.2Al.sub.3O.sub.12, or other rare earth gallium aluminum garnets, with different ions can modify the scintillation light yield, decay time, rise time, energy resolution, proportionality, and/or sensitivity to light exposure. Also provided are the codoped garnet-type scintillators themselves, radiation detectors and related devices comprising the codoped garnet-type scintillators, and methods of using the radiation detectors to detect gamma rays, X-rays, cosmic rays, and particles having an energy of 1 keV or greater.

Methods for producing a single crystal silicon ingot using boric acid as a dopant and ingot puller apparatus that use a solid-phase dopant

Methods for producing a single crystal silicon ingot are disclosed. The ingot is doped with boron using solid-phase boric acid as the source of boron. Boric acid may be used to counter-dope the ingot during ingot growth. Ingot puller apparatus that use a solid-phase dopant are also disclosed. The solid-phase dopant may be disposed in a receptacle that is moved closer to the surface of the melt or a vaporization unit may be used to produce a dopant gas from the solid-phase dopant.