A power semiconductor device comprising a gate-commutated thyristor cell, a first main side and a second main side opposite to the first main side, wherein the gate-commutated thyristor cell comprises in the order from the first main side to the second main side: - a cathode electrode arranged on the first main side, - a cathode region of a first conductivity type, - a base layer of a second conductivity type different than the first conductivity type forming a first junction to the cathode region, - a drift layer of the first conductivity type forming a second junction with the base layer, - an anode layer of the second conductivity type, and - an anode electrode arranged on the second main side, wherein the gate-commutated thyristor cell further comprise a gate electrode which is arranged lateral to the cathode region, wherein the base layer comprises: - a cathode base region located between the cathode region and the drift layer and having a first thickness, - a gate base region located between the gate electrode and the drift layer and having a second thickness, and - an intermediate base region located between the cathode base region and the gate base region and having at least two different values of a third thickness, wherein the at least two values of the third thickness are both larger than the first thickness and smaller than the second thickness, characterized in that - the part of the second junction which is located between the intermediate base region and the drift layer includes: - a first base transition region forming a step, - a second base transition region forming a further step and - a plane between the first and the second base transition region (10, 11). - a cathode electrode arranged on the first main side, - a cathode region of a first conductivity type, - a base layer of a second conductivity type different than the first conductivity type forming a first junction to the cathode region, - a drift layer of the first conductivity type forming a second junction with the base layer, - an anode layer of the second conductivity type, and - an anode electrode arranged on the second main side, wherein the gate-commutated thyristor cell further comprise a gate electrode which is arranged lateral to the cathode region, wherein the base layer comprises: - a cathode base region located between the cathode region and the drift layer and having a first thickness, - a gate base region located between the gate electrode and the drift layer and having a second thickness, and - an intermediate base region located between the cathode base region and the gate base region and having at least two different values of a third thickness, wherein the at least two values of the third thickness are both larger than the first thickness and smaller than the second thickness, characterized in that - the part of the second junction which is located between the intermediate base region and the drift layer includes: - a first base transition region forming a step, - a second base transition region forming a further step and - a plane between the first and the second base transition region (10, 11). - a cathode base region located between the cathode region and the drift layer and having a first thickness, - a gate base region located between the gate electrode and the drift layer and having a second thickness, and - an intermediate base region located between the cathode base region and the gate base region and having at least two different values of a third thickness, wherein the at least two values of the third thickness are both larger than the first thickness and smaller than the second thickness, characterized in that - the part of the second junction which is located between the intermediate base region and the drift layer includes: - a first base transition region forming a step, - a second base transition region forming a further step and - a plane between the first and the second base transition region (10, 11). - a first base transition region forming a step, - a second base transition region forming a further step and - a plane between the first and the second base transition region (10, 11).