Coating material for absorbing radiant heat, manufacturing method thereof

A crystal growing apparatus for growing silicon single crystals from silicon melt, a silicon single crystal growing apparatus comprising:

• a quartz crucible;
• a heating element;
• a crystal pulling device;
• a heat shield for maintaining a proper temperature distribution in the crystal growing system;
• and
• a cooling device,
• wherein the quartz crucible, heating element, crystal pulling device, heat shield, and cooling device are installed inside a sealed furnace or a sealed crystal growing apparatus,
• wherein the silicon/crystal growing apparatus further comprises a crystal cooling means for cooling the growing crystal by absorbing radiant heat emitted from the crystal, and
• wherein the crystal cooling means includes a circulating cooling pipe inside and a crystal radiant heat absorbing layer coated on an outer surface of the cooling means.

A cooling apparatus for absorbing radiant heat emitted from the crystal and transferring heat outside the crystal growing apparatus or furnace, a radiant heat cooling apparatus comprising:

• a circulating cooling pipe inside;
• and
• a radiant heat absorbing layer coated on an outer surface of the cooling means,
• wherein the radiant heat absorbing layer is formed by coating a radiant heat absorbing coating material, which is prepared by agitating to mix 10˜15 wt/% of silica gel, 5˜10 wt/% of graphite powder, and 75˜85 wt/% of IPA(isopropyl alcohol) with each other, thereon and drying the coated radiant heat absorbing coating material.