| 摘要 |
A semiconductor device is provided to restrain a reverse current flowed into an IGBT(Insulate Gate Bipolar Transistor) by using a short carrier life time region and improving a reverse withstand voltage of the IGBT. The semiconductor device is comprised of a first conductivity type semiconductor layer, a second conductivity type base region(3), a first conductivity type emitter region(4), a first conductivity type buffer layer(1), and a second conductivity type collector layer(8). A maximum value of a first conductive type impurity concentration of the buffer layer is less 5X10^15cm^-3 and a maximum value of a second type impurity concentration of the collector layer is over 1X10^17cm^-3. The maximum value of the collector layer is more 100 times than that of the buffer layer. A thickness of the collector layer is greater than about 1 micro meter. |
