A device for growing large-sized monocrystalline crystals, including a crucible adapted to grow crystals from a material source and with a seed crystal and including therein a seed crystal region, a growth chamber, and a material source region; a thermally insulating material disposed outside the crucible and below a heat dissipation component; and a plurality of heating components disposed outside the thermally insulating material to provide heat sources, wherein the heat dissipation component is of a heat dissipation inner diameter and a heat dissipation height which exceeds a thickness of the thermally insulating material.