Disclosed are a
polycrystalline silicon ingot, a method for producing the same, and a
crucible. The
crucible has a rough bottom surface, and has a plurality of three-dimensional geometrical shapes of
spatial distribution; the inner surface of the
crucible is coated with at least one
coating, and there are particulate substances as heterogeneous
nucleation sites for
silicon in the
coating on the bottom surface of the crucible. According to an embodiment of the present invention, the bottom surface of the crucible is coated with at least one
coating, and the particulate substances in the coating can be used as
silicon nucleation sites during the subsequent
crystal growth, inhibit the formation of
crystal nuclei in other regions, so that the distribution of
crystal grains is more uniform. In addition, crystal grains whose nuclei are formed first start to compete in a pit at the bottom surface of the crucible, and crystal grains with a certain
crystal orientation predominate during the competing process and are ultimately retained, so the orientations of the nuclei tend to be consistent, i.e., the
polycrystalline silicon ingot grown according to the method has a uniform crystal grain size, and a consistent crystal
grain orientation, and has a reduced
dislocation density inside the crystal and a prolonged minority
carrier lifetime, thereby increasing the conversion efficiency of the
polycrystalline silicon solar battery.