Device for etching semiconductors with a large surface area

Apparatus for etching large-surface semiconductor wafers (32) in a trough-shaped receptacle (10) with a liquid electrolyte, with at least one probe head (12) within a movably mounted etching trough (10) which is provided with means for holding at least one semiconductor wafer (32) wherein a swing device the electrolyte is set in motion, characterized in that - The probe head (12) with the surface to be etched is arranged downward in the etching trough (10), - Exchangeable for setting different electrolyte layer thicknesses of spacers (26) are provided for the distance between Ätztrogboden and probe head (12), - And are provided for an electrochemical etching on the sample head (12) electrical contacts for contacting the back of the semiconductor wafer (32).