| 摘要 |
PROBLEM TO BE SOLVED: To obtain a semiconductor device in which significant increase of stored charges is prevented during conductive operation by the peripheral edge by doping such dopant as having a specified low impurity energy level with respect to the peripheral edge. SOLUTION: A dopant having at least one kind of low impurity energy level higher than about 0.1eV with respect to the peripheral edge 4 is doped. The dopant atom built in a silicon crystal lattice at the peripheral edge 4 is not ionized substantially within a specified working temperature range based on its low energy level. Consequently, the voltage drop on a active range is confined within the voltage drop of a parasitic pn diode formed by the peripheral edge 4 and a semiconductor region 2 doped with reverse polarity when a semiconductor device is conducting and the peripheral edge 4 hardly emit a charge carrier. Consequently, additional generation of stored charge can be substantially prevented by the peripheral edge 4, especially in a unipolar semiconductor device. |
