Systems and methods for producing a single crystal silicon ingot using a vaporized dopant

An ingot puller apparatus for producing a doped single crystal silicon ingot, the ingot puller apparatus comprising:

• a housing defining a chamber maintained at a pressure below atmospheric pressure;
• a crucible disposed within the chamber;
• a heater to radiate heat in the chamber;
• and
• a dopant injector attached to and extending into the housing, the dopant injector comprising:
• a feed tube positioned within the chamber to receive a liquid dopant;
• and
• a vaporization cup positioned within the feed tube and the chamber to vaporize the liquid dopant into a vaporized dopant;
• wherein the vaporization cup is maintained at the pressure below atmospheric pressure in the chamber and heated by radiant heat from the heater such that the vaporization cup operates to vaporize the liquid dopant by flash evaporation.

A method for producing a single crystal silicon ingot, the method comprising:

• adding polycrystalline silicon to a crucible disposed within a chamber defined by a housing of an ingot puller apparatus;
• maintaining the chamber at a first pressure;
• heating the chamber using radiant heat to melt the polycrystalline silicon and form a silicon melt in the crucible;
• pulling a single crystal silicon ingot from the silicon melt;
• channeling a liquid dopant at a second pressure greater than the first pressure into a feed tube positioned in the chamber;
• vaporizing the liquid dopant into a vaporized dopant by flash evaporation at the first pressure within the feed tube;
• and
• directing the vaporized dopant from the feed tube toward a surface of the silicon melt to cause the vaporized dopant to enter the silicon melt as a dopant while pulling the single crystal silicon ingot from the silicon melt.