| 摘要 |
PURPOSE:To improve the commutation characteristics of the reverse conductivity thyristor by forming the reverse recovery charge of a diode portion therein larger than that of a thyristor portion when forming a thyristor portion and an anti-parallel diode portion on the same semiconductor substrate to form the reverse conductivity thyristor. CONSTITUTION:P-type layers 4 and 5 are diffused on both front and back surfaces of an N-type semiconductor substrate 8, and an N-type region 2 is formed in the layer 4. An N<+>-type region 7 making contact with the substrate 8 is diffused at an interval without superimposing with the region 2 in the layer 5, and one end including the region 2 of the substrate 8 is formed in a thyristor portion A of PNPN structure. The other end including the region 7 opposite thereto is formed in diode portion of N<+>NP structure, and the PNP portion C disposed between the portions A and B is formed as an isolating region to form the reverse conductivity thyristor. In order to reduce the lefetime in this configuration, when Au is diffused, only the diode portion B is coated with oxide film so that the Au density is lowered than the other portions A and C. |
