| 摘要 |
PURPOSE:To control bipolar action and to avoid a decrease in dielectric strength between a source and a drain by a method wherein drain region width is broadened more than source region width when a source region and a drain region are formed on a semiconductor substrate and a channel region locating between these regions are spreaded in fan shape. CONSTITUTION:An N<+> type source region 12 and an N<+> type drain region 13 are formed on a P type Si substrate and a gate electrode 14 consisting of polycrystalline Si is formed on a channel region locating between the regions 12 and 13 through a gate insulating film and the circumferences of the regions 12 and 13 are surrounded by a thick field oxide film 11. In this composition, the drain region 13 width is broadened more than the source region 12 width to form the channel region locating between the regions 12 and 13 in sector shape. In this way, electric charge density at the channel becomes lower toward the drain side from the source side and electric field strength decreases at the drain side to control bipolar action and it is possible to prevent a decrease in dielectric strength. |
