Method of welding single crystals

1A method of single crystal welding is provided for the production of a single crystal region on a surface of a moncrystalline substrate by means of an energy beam. The method of single crystal welding includes the supply of a coating material, the formation of a melt by melting the coating material by means of the energy beam and the melting of a surface layer of the single crystal substrate by the energy beam. The characteristic of the energy distribution in the energy beam is set, in this connection, such that the lateral thermal flow (H) from the melt into the single crystal substrate is minimized.