Patent classifications
Y10T117/1068
Apparatus and method for controlling thickness of a crystalline sheet grown on a melt
An apparatus may include a crucible configured to contain the melt, the melt having an exposed surface separated from a floor of the crucible by a first distance, a housing comprising a material that is non-contaminating to the melt, the housing comprising a plurality of sidewalls and a top that are configured to contact the melt, and a plurality of heating elements isolated from the melt and disposed along a transverse direction perpendicular to a pulling direction of the crystalline sheet, the plurality of heating elements being individually powered, wherein the plurality of heating elements are disposed at a second set of distances from the exposed surface of the melt that are less than the first distance, and wherein the plurality of heating elements are configured to vary a heat flux profile along the transverse direction when power is supplied individually to the plurality of heating elements.
METHOD FOR ACHIEVING SUSTAINED ANISOTROPIC CRYSTAL GROWTH ON THE SURFACE OF A SILICON MELT
An apparatus for growing a crystalline sheet from a melt includes a cold block assembly. The cold block assembly may include a cold block and a shield surrounding the cold block and being at an elevated temperature with respect to that of the cold block, the shield defining an opening disposed along a surface of the cold block proximate a melt surface that defines a cold area comprising a width along a first direction of the cold block, the cold area operable to provide localized cooling of a region of the melt surface proximate the cold block. The apparatus may further include a crystal puller arranged to draw a crystalline seed in a direction perpendicular to the first direction when the cold block assembly is disposed proximate the melt surface.
Method for achieving sustained anisotropic crystal growth on the surface of a silicon melt
An apparatus for growing a crystalline sheet from a melt includes a cold block assembly. The cold block assembly may include a cold block and a shield surrounding the cold block and being at an elevated temperature with respect to that of the cold block, the shield defining an opening disposed along a surface of the cold block proximate a melt surface that defines a cold area comprising a width along a first direction of the cold block, the cold area operable to provide localized cooling of a region of the melt surface proximate the cold block. The apparatus may further include a crystal puller arranged to draw a crystalline seed in a direction perpendicular to the first direction when the cold block assembly is disposed proximate the melt surface.
SINGLE CRYSTAL INGOTS WITH REDUCED DISLOCATION DEFECTS AND METHODS FOR PRODUCING SUCH INGOTS
An improved system based on the Czochralski process for continuous growth of a single crystal ingot comprises a low aspect ratio, large diameter, and substantially flat crucible, including an optional weir surrounding the crystal. The low aspect ratio crucible substantially eliminates convection currents and reduces oxygen content in a finished single crystal silicon ingot. A separate level controlled silicon pre-melting chamber provides a continuous source of molten silicon to the growth crucible advantageously eliminating the need for vertical travel and a crucible raising system during the crystal pulling process. A plurality of heaters beneath the crucible establish corresponding thermal zones across the melt. Thermal output of the heaters is individually controlled for providing an optimal thermal distribution across the melt and at the crystal/melt interface for improved crystal growth. Multiple crystal pulling chambers are provided for continuous processing and high throughput.
ADVANCED CRUCIBLE SUPPORT AND THERMAL DISTRIBUTION MANAGEMENT
An advanced crucible support system is described that allows for greater heat flow to and from the bottom of a crucible, preferably while also preventing excessive heat from reaching a heat exchanger. In particular, a support base is described that includes a plurality of spaced crown features disposed on the support base plate. The crown features receive and vertically support the crucible and are spaced to support the crucible and to allow heat flow between the plurality of crown features. In doing so, a top surface of spaced crown features are in direct contact with the crucible.
Crystal pulling systems having a cover member for covering the silicon charge
Crystal pulling system having a housing and a crucible assembly are disclosed. The system includes a heat shield that defines a central passage through which an ingot passes during ingot growth. A cover member is moveable within the heat shield along a pull axis. The cover member may include an insulation layer. The cover member covers at least a portion of the charge during meltdown.
Crystal pulling systems having a cover member for covering the silicon charge and methods for growing a melt of silicon in a crucible assembly
Crystal pulling system having a housing and a crucible assembly are disclosed. The system includes a heat shield that defines a central passage through which an ingot passes during ingot growth. A cover member is moveable within the heat shield along a pull axis. The cover member may include an insulation layer. The cover member covers at least a portion of the charge during meltdown.
Apparatus for manufacturing single crystal
The present invention provides an apparatus for manufacturing a single crystal according to a Czochralski method, including: a crucible configured to contain a raw material melt; a cylindrical heater surrounding the crucible, the heater being configured to heat the raw material melt; a main chamber that accommodates the crucible and the heater; an electrode that is inserted from the bottom of the main chamber and supports the cylindrical heater, the electrode being configured to supply electric power to the heater; and a melt-leakage receiving tray disposed on the bottom of the main chamber, the tray being configured to receive the raw material melt leaking from the crucible, wherein a melt-leakage cover is disposed below the crucible and above the electrode, the cover being configured to prevent contact between the raw material melt leaking from the crucible and the electrode.
CRYSTAL PULLING SYSTEMS AND METHODS FOR PRODUCING MONOCRYSTALLINE INGOTS WITH REDUCED EDGE BAND DEFECTS
A crystal pulling system for growing a monocrystalline ingot from a melt of semiconductor or solar-grade material includes a crucible for containing the melt of material, a pulling mechanism configured to pull the ingot from the melt along a pull axis, and a multi-stage heat exchanger defining a central passage for receiving the ingot as the ingot is pulled by the pulling mechanism. The heat exchanger defines a plurality of cooling zones arranged vertically along the pull axis of the crystal pulling system. The plurality of cooling zones includes two enhanced-rate cooling zones and a reduced-rate cooling zone disposed vertically between the two enhanced-rate cooling zones.
Manufacturing apparatus of SiC single crystal and method for manufacturing SiC single crystal
An apparatus for SIC single crystal has an induction heating control unit such that frequency f (Hz) of alternating current to the induction heating unit satisfies Formula (1); D1 (mm) is permeation depth of electromagnetic waves into a crucible side wall by the heating unit, D2 (mm) is permeation depth of electromagnetic waves into a SIC solution, T (mm) is thickness of the crucible side wall of the crucible, and R (mm) is crucible inner radius:
(D1T)D2/R>1.5(1) where, D1 is defined by Formula (2) and D2 by Formula (3):
D1=503292(1/(fcc)).sup.1/2(2)
D2=503292(1/(fss)).sup.1/2(3); c is electric conductivity (S/m) of the sidewall, s is electric conductivity (S/m) of the SiC solution; c is relative permeability of the sidewall, and s is relative permeability of the SIC solution.