| 摘要 |
PURPOSE:To prevent the effect of a parasitic channel formed in the side surface of a semiconductor region, which is separated in an island shape, by providing both source and drain regions so that they are not contacted with the side surface of a single crystal silicon island in a trapezoidal shape. CONSTITUTION:On an insulating substrate 11, a p-type single crystal silicon island 12 is formed in a trapezoidal shape. Polycrystalline silicon 15, which is to become a gate electrode, is formed in a (-) shape through a gate insulating film 14. An n-type source region 12a and a drain region 12b are formed by an ion implantation method with the polycrystalline silicon 15 as a mask. Therefore, both regions 12a and 12b have a structure, in which they are not contacted with the side surface of the single crystal island. As shown by a one-dot chain line, the polycrystalline silicon gate electrode 15 is formed in the gate forming region and further formed in a region, which is connected to said gate forming region and surrounds the single crystal silicon 12. Since both source and drain regions 12a and 12b are not connected to a parasitic channel region, the regions are not subjected to the effect of the parasitic channel. |
