The Fig. shows the various parameters pertaining to IGBT characteristics.

Static V-I or output characteristics of an IGBT (n-channel type) show the plot of collector current $I_C$ versus collector-emitter voltage $V_{CE}$ for various values of gate-emitter voltages. These characteristics are shown in above Fig. In the forward direction, the shape of the output characteristics is similar to that of BJT. But here the controlling parameter is gate-emitter voltage $V_{GE}$ because IGBT is a voltage-controlled device.

The transfer characteristic of an IGBT is a plot of collector current $I_C$ versus gate-emitter voltage $V_{GE} $ as shown in above Fig. This characteristic is identical to that of power MOSFET. When $V_{GE}$ is less than the threshold voltage $V_{GET}$ IGBT is in the off-state.

When the device is of‌f, junction $J_2$ blocks forward voltage and in case reverse voltage appears across collector and emitter, junction $J_1$ blocks it.