Patent ID: 7439198

Claim:
A method for fabricating a buried metallic layer at a predetermined vertical position in a semiconductor body having a first and second side, wherein the semiconductor body comprises a first and a second semiconductor layer arranged one above the other in the vertical direction of the semiconductor body, of which layers one forms the first side and the other forms the second side of the semiconductor body, wherein the first semiconductor layer is doped more heavily than the second semiconductor layer, which method comprises: applying a metal layer to one of the first and second sides at least in sections, wherein the buried metallic layer is produced in the semiconductor layer adjoining the one side to which the metal layer is applied; establishing a positive temperature gradient in a vertical direction of the semiconductor body proceeding from the one side, the temperature in the region of the one side being higher than the eutectic temperature of a system comprising the material of the metal layer and the semiconductor material of the semiconductor body so that the metal of the metal layer migrates in the vertical direction into the semiconductor body; discontinuing the temperature gradient once the metal reaches the predetermined vertical position in the semiconductor body in order thereby to obtain the metallic layer at the predetermined position; and fabricating at least one metallic terminal connection extending in the vertical direction of the semiconductor body proceeding from one of the sides as far as the metallic layer.