Semiconductor device

A semiconductor device comprising:

• a reverse conducting switching device including a diode device and a switching device, which are arranged in parallel at a single semiconductor substrate;
• a driver configured to apply a gate voltage to a plurality of gate electrodes included in the reverse conducting switching device;
• and
• a mode determination unit configured to determine whether
• a forward conduction mode in which a current flows mainly in the switching device, or
• a reverse conduction mode in which the current flows mainly in the diode device is operated in the reverse conducting switching device,
• wherein the diode device includes
• a first impurity region having a first conduction type,
• a second impurity region having a second conduction type which is coupled to the first impurity region,
• a first electrode configured to electrically connected to the first impurity region, and
• a second electrode configured to electrically connected to the second impurity region,
• wherein an inverted layer is generated in the first impurity region in response to applying a predetermined gate voltage to the plurality of gate electrodes, and
• wherein the switching device and the diode device commonly share the first electrode and the second electrode, respectively,
• wherein the switching device is turned on to control a current flow between the first electrode and the second electrode in response to applying the predetermined gate voltage to the plurality of gate electrodes,
• wherein the plurality of gate electrodes includes
• a first gate electrode to which a first gate voltage for turning on the switching device is input, and
• a second gate electrode to which a second gate voltage is input, the second gate voltage being controlled independently of the first gate voltage, the second gate voltage having a potential level same as a potential level at the second electrode or the second gate voltage having a polarity opposite from a polarity of the first gate voltage with reference to the potential level at the second electrode,
• wherein one part of the plurality of gate electrodes in the diode device includes at least the second gate electrode, and another part of the plurality of gate electrodes in the switching device includes at least the first gate electrode, and
• wherein the second gate voltage is applied to the second gate electrode
• in response to determining the reverse conducting switching device being operated in the reverse conduction mode based on the current flowing between the first electrode and the second electrode, or
• in response to the mode determination unit being unable to determine whether the reverse conduction mode or the forward conduction mode is operated in the reverse conducting switching device.