SEMICONDUCTOR DEVICE AND MANUFACTURE THEREOF

摘要

PURPOSE:To avoid any leakage current by a method wherein a shield layer comprising a conductive layer is provided between the side-wall and a capacitor electrode in a trench adjacent to a transistor region. CONSTITUTION:A shield layer 13 is provided between the channel part of a parasitic MOS transistor Tr and a capacitor electrode 12; said transistor Tr can be prevented from becoming conductive to avoid any leakage current even if the capacitor electrode 12 is impressed with high potential by electrically connecting this shield layer 13 to a substrate 11 to provide the shield layer 13 with the same potential as that of the substrate 11. Consequently, a capacitor accumulating electrode can work as a gate electrode of the parasitic MOSFET cell in e.g., a DRAM cell using a trench capacitor 10 so that a large capacity of a capacitor may be maintained to avoid the leakage current thereof by using the shield layer 13 of this invention in a semiconductor device subjected to the leakage current between source and drain.