Wafer contacting device, and arrangement and method for electrochemical etching of a wafer

An arrangement for electrochemical etching of a wafer, comprising:

• a wafer contacting device, comprising:
• a holder comprising a receiving region configured to receive a wafer;
• an elastically deformable carrier disposed in the receiving region and comprising an electrically conductive surface region;
• and
• a retainer placed over the holder, wherein the retainer comprises a contacting structure, which is in electrical contact with a second side of the wafer at a boundary region of the wafer
• wherein the wafer is disposed over the elastically deformable carrier in the receiving region and retained by the retainer, wherein the electrically conductive surface region is in contact with at least a portion of a first side of the wafer;
• an electrolyte in contact with at least a portion of the second side of the wafer opposite the first side
• at least one voltage source coupled to the electrically conductive surface region of the carrier and to the electrolyte, and configured to apply a first electrical potential to the electrically conductive surface region and to apply a second electrical potential to the electrolyte.

A method for electrochemical etching of a wafer, comprising:

• disposing a wafer over an elastically deformable carrier comprising an electrically conductive surface region, at least a portion of a first side of the wafer being coupled to the electrically conductive surface region of the carrier, the wafer comprising a stack comprising at least a first semiconductor region of a first conductivity type and a second semiconductor region of a second conductivity type disposed adjacent to the first semiconductor region, wherein the first semiconductor region is proximate the first side of the wafer and the second semiconductor region is proximate a second side of the wafer that is opposite the first side;
• disposing a retainer to retain the wafer, wherein the retainer comprises a contacting structure configured to electrically contact the second side of the wafer;
• coupling a first electrical potential to the electrically conductive surface region of the elastically deformable carrier;
• exposing at least a portion of the second side of the wafer to an electrolyte;
• and
• coupling a second electrical potential to the electrolyte, wherein the second electrical potential is lower than the first electrical potential.