Semiconductor device having a lightly doped layer and power converter comprising the same

摘要

In a semiconductor device such as a pn-junction diode, a Schottky diode, a JFET, a MOSFET or a MESFET, a drift layer is made of two layers, a first layer (12) and a second layer (13) having the same conductivity type as that of the first layer (12) and being disposed on said first layer (12), a termination region being formed on the surface of said second layer (13). The impurity concentration of the second layer (13) is less than half that of the first layer (12). The thickness of the second layer may moreover be made smaller than that of a main layer (14) of the device. In accordance with the above features, the field intensity is reduced at the termination region of the device. <IMAGE>