A semiconductor crystal control system for modifying a crystal growth process of silicon carbide is provided. The system can obtain one or more crystal growth parameters associated with growing a semiconductor crystal in a crystal growth assembly. The system can determine, based on the one or more crystal growth parameters, a predicted growth condition. The system can modify a crystal growth process based at least in part on the predicted growth condition.

Silicon carbide substrates are in demand for high power applications such as electric vehicles, solar panels, and industrial electronics. A physical vapor transport (PVT) reactor for growth of silicon carbide ingots can be improved by attaching a cooling assembly to a top end of a PVT growth crucible. By varying the number, size, and spacing of cooling elements within the cooling assembly, radial temperature variation inside the PVT growth crucible can be adjusted, independent of axial temperature variation. More uniform radial temperature profiles result in lower stress, fewer crystal defects, and improved silicon carbide wafer quality.

A semiconductor wafer providing method performed by a first entity includes: an acquisition step of acquiring a remaining wafer from a second entity; a fabrication step of fabricating a slice surface of the remaining wafer; a growth step of causing a semiconductor crystal layer to grow on the fabricated surface of the remaining wafer; and a wafer providing step of providing a new semiconductor wafer having at least part of the semiconductor crystal layer, which has grown on the fabricated surface of the remaining wafer, to a second entity which is the same as or different from the second entity that is an acquisition source of the remaining wafer.