The Kyropoulos process is a variation of the Czochralski process.
The special feature of this process is that this base material is completely melted and then a single crystal is grown by directional solidification. The seed crystal is not pulled out of the melt, but grows in the melt as a result of a gradual reduction in heat generation.
The process allows the cultivation of large diameter sapphire ingots of very good quality (homogeneity) because the melting movement is very low. The process lasts from a few days to several weeks.