SEMICONDUCTOR INTEGRATED CIRCUIT DEVICE AND MANUFACTURING METHOD THEREFOR

摘要

PURPOSE: To prevent defects that oxygen through a lower electrode oxidizes the surface of a silicon plug at a lower layer, and that the oxide layer of high resistance is formed when a dielectric film formed on the lower electrode of a capacitive element in DRAM is thermally treated in an oxygen atmosphere. CONSTITUTION: Since a polycrystalline silicon film 28 is formed along the inner wall of a groove 27 where the capacitive element is formed and the polycrystalline silicon film 28 is brought into contact with the lower electrode 29 in the whole inner wall of the groove 27, oxygen intruding into the lower electrode 29 at the time of heat treating a tantalum oxide film 32 is consumed in the interface of the polycrystalline silicon film 28 and the lower electrode 29, and it is prevented from reaching the surface of a plug 22.