Method of operating a semiconductor device having a desaturation channel structure

A method of operating a semiconductor device which comprises an IGBT comprising a first electrode terminal, a second electrode terminal, a gate electrode terminal, and a desaturation semiconductor structure comprising a desaturation channel, the desaturation semiconductor structure being connected to the first electrode terminal and the gate electrode terminal for controlling the desaturation channel, the method comprising:

• applying a first gate voltage to the gate electrode terminal so that current flows through the IGBT between the first electrode terminal and the second electrode terminal and so that current flow through the desaturation channel is substantially blocked;
• applying a second gate voltage different than the first gate voltage to the gate electrode terminal so that current flows through the IGBT between the first electrode terminal and the second electrode terminal and so that charge carriers flow as a desaturating current through the desaturation channel of the desaturation semiconductor structure to the first electrode terminal;
• and
• applying a third gate voltage different than the first and second gate voltages to the gate electrode terminal so that current flow through the IGBT between the first electrode terminal and the second electrode terminal is substantially blocked,
• wherein the semiconductor device further comprises a first IGBT cell including a gate electrode, a first electrode, a second electrode and a drift region, the gate electrode being connected to the gate electrode terminal, the first electrode being connected to the first electrode terminal, and the second electrode being connected to the second electrode terminal,
• wherein when the first or second gate voltage is applied to the gate electrode terminal, current flows through the first IGBT cell between the first electrode terminal and the second electrode terminal.