Method and apparatus for large-area electrical contacting of a semiconductor crystal body with the assistance of electrolytes

A method of establishing large-area electrical contacting of a semiconductor crystal body which includes a first side with a first surface and a second side with a second surface, comprising the steps of:

• applying a first cell having a first electrode therein to the first side such that the first
• surface is exposed to the interior of the first cell;
• applying a second cell having a second electrode therein to the second side such that
• the second surface is exposed to the interior of the second cell;
• filling at least the second cell with an electrolyte to directly contact the second surface
• and the second electrode;
• applying a voltage between the first and second electrodes;
• illuminating the second surface;
• and
• controlling the intensity of illumination of the second surface to control a current flow between said first and second electrodes through the semiconductor crystal body.

Apparatus for large-area electrical contacting of a semiconductor crystal body which comprises a first side including a first surface and an opposite second side including a second surface, comprising:

• a hollow first cell, including a first electrode therein,
• connected to said first side to expose said first surface to the interior of
• said first cell;
• a hollow second cell, including a second electrode therein, connected to said second side
• to expose said second surface to the interior of said second cell;
• electrolyte filling at least said second cell and in contact with said second electrode and
• said second surface;
• voltage means for applying a voltage between said first and second electrodes,
• including at least one voltage source;
• and light means for illuminating the semiconductor crystal body;
• aid voltage means, said electrolyte and said light means causing a current flow from said first electrode through the semiconductor body to said second electrode with the aid of at least one control parameter,
• at least one said voltage means, said electrolyte and said light means being variable in, respectively, voltage, type of electrolyte concentration of electrolyte, and intensity of illumination of at least one of said first and second surfaces of said semiconductor body to control current flow.