Power semiconductor device

The invention provides a power semiconductor device which comprises a cellular area, a transition area and a terminal area, and the transition area is located between the cellular area and the terminal area of the device. The bottoms of the device cellular region, the transition region and the terminal region are jointly provided with a first conductive type substrate, a first conductive type epitaxial layer located above the first conductive type substrate and a first conductive type buffer layer located in the first conductive type epitaxial layer; under the application of large current, as the cellular region is the region with the maximum area proportion in the chip, if breakdown can occur in the cellular region, the current is discharged through the cellular region, and the robustness of the device is greatly improved; on the basis of ensuring the withstand voltage of the terminal region, the longitudinal withstand voltage length of the terminal region is improved by raising the position of the top struc